Frequently Asked Questions

Common questions about Nexifr and our tools.

Are my files uploaded to a server?

Most file transformations run in your browser. A small number of tools use a public provider or a Nexifr processing service; the relevant tool page shows a data-handling notice before you use it. Do not submit sensitive material to a network-enabled tool.

Is Nexifr really free?

Yes. All 136 tools are completely free to use. We may introduce premium features in the future, but the core tools will remain free.

Do I need to create an account?

No account or login is required. Just open any tool and start using it immediately.

What browsers are supported?

Nexifr works on all modern browsers including Chrome, Firefox, Safari, and Edge. We recommend keeping your browser up to date for the best experience.

How do you make money?

We use non-intrusive ads and may offer premium features (like advanced export options) in the future. Your data privacy remains our top priority.

Can I use Nexifr for commercial projects?

Yes. All tools are free to use for both personal and commercial projects. See our Terms of Service for details.

Is image compression lossy?

Yes, we use canvas-based compression which is lossy. Adjust the quality slider to control the trade-off.

— from Image Compressor

Are my images uploaded to a server?

No. All processing happens entirely in your browser.

— from Image Compressor

What formats are supported?

We support PNG, JPEG, WebP, BMP, GIF (static frame), ICO, and PDF exports.

— from Image Converter

Is the PDF generation safe and private?

Yes. The PDF is compiled entirely in your browser. The image is wrapped into a clean, lightweight PDF structure, so your files never upload to any server.

— from Image Converter

Can I convert high-resolution images?

Yes, since the conversion runs on your local machine using standard HTML5 Canvas buffers, there are no payload limits or internet bandwidth caps.

— from Image Converter

Are my HEIC images uploaded to a server?

No. The entire conversion runs directly in your browser using local WebAssembly, ensuring complete privacy.

— from HEIC to JPEG/PNG Converter

Why convert HEIC files?

HEIC is Apple's high-efficiency image format. While it saves space on iOS, many websites, Windows apps, and printing services do not support it.

— from HEIC to JPEG/PNG Converter

Is there a limit on how many files I can merge?

This tool currently allows uploading and merging up to 5 files at a time. The only boundary is your device's browser memory.

— from Merge PDF

Are my documents safe?

Yes, merging happens completely offline in your browser. No files are ever sent to a server.

— from Merge PDF

Does resizing affect quality?

Downscaling preserves quality well. Upscaling may cause pixelation.

— from Image Resizer

What does SVG optimization do?

It removes unnecessary attributes, whitespace, comments, and metadata to reduce file size.

— from SVG Optimizer

Can I scan QR codes generated here?

Yes. All QR codes generated by this tool are standard QR Code version 1–40 compliant, meaning any smartphone camera app (iOS, Android) or dedicated QR scanner app will read them instantly. No special app or Nexifr account is required to scan the codes.

— from QR Code Generator

What can I encode in a QR code?

You can encode URLs (website links), plain text, email addresses, phone numbers, SMS messages, Wi-Fi network credentials (SSID + password), vCard contact information, and geographic coordinates. The most common use is encoding a website URL for use in print or physical materials.

— from QR Code Generator

Do the QR codes expire?

No. Unlike QR codes generated by URL-shortening services (like Bitly's QR feature), Nexifr generates static QR codes that directly encode your content — there is no redirect URL, no tracking server, and no expiry. Your QR code will keep working forever as long as the destination URL remains active.

— from QR Code Generator

What file format can I download the QR code in?

The generated QR code can be downloaded as a high-resolution PNG image. It is suitable for both digital use (websites, emails, social media) and print use (business cards, flyers, packaging). For vector print use, you can scale the PNG at a large size (500px) and save at high resolution.

— from QR Code Generator

Are images uploaded before rotating?

No. The rotation uses your browser's canvas engine, so the file stays on your device.

— from Image Rotator

Which output format should I choose?

PNG keeps transparency, JPEG is broadly compatible, and WebP usually gives smaller files.

— from Image Rotator

Does flipping change the original file?

No. The browser creates a new downloadable output and leaves the source file untouched.

— from Image Flipper

Can I choose the crop position?

This version uses a centered crop for speed and consistency. It works best for product images, thumbnails, and social graphics.

— from Image Cropper

Does it preserve transparency?

PNG and WebP outputs can preserve transparency. JPEG uses a white background.

— from Image Cropper

What is Lorem Ipsum?

Lorem Ipsum is standard placeholder text used in design and typesetting to mimic readable copy without distracting the reader with real content.

— from Lorem Ipsum Generator

Is my microphone audio private?

Yes, absolutely. The recording and processing are handled 100% locally on your machine. Your audio is never sent to any server.

— from Voice Recorder & Audio Visualizer

What file format is exported?

The tool exports standard audio formats supported by your browser (typically WebM or WAV).

— from Voice Recorder & Audio Visualizer

What audio formats are supported?

The tool supports formats your browser can decode, commonly MP3, WAV, OGG, and M4A.

— from Audio Trimmer

Why is the output WAV?

WAV can be created reliably in the browser without sending the audio to a server.

— from Audio Trimmer

Can increasing volume distort audio?

Very high gain can clip loud peaks. The processor limits peaks to avoid broken output, but moderate values sound cleaner.

— from Audio Volume Changer

Is my audio uploaded?

No. Decoding, gain adjustment, and WAV export all happen inside the browser.

— from Audio Volume Changer

Does reversing work for long audio?

It can, but very long files depend on your device memory because all processing is local.

— from Audio Reverse

Are my files uploaded to a server?

Yes. The selected video is sent to Nexifr's processing service so FFmpeg can extract the audio. Do not upload sensitive video.

— from Video to Audio Extractor

What video formats are supported?

Most standard container formats are supported, including MP4, WebM, MOV, AVI, and MKV.

— from Video to Audio Extractor

Why is the trimming so fast?

The processing service uses FFmpeg to create the requested clip. The processing time depends on the source file, selected duration, and server capacity.

— from Video Trimmer

Will compressing decrease video quality?

Yes, compression reduces the bitrate or resolution to shrink file size. Use 'Low Compression' to maximize quality.

— from Video Compressor

What meta tags are generated?

Standard meta, Open Graph, Twitter Card, and viewport tags are included.

— from Meta Tag Generator

Is JSON-LD the right format?

Yes, JSON-LD is Google's recommended structured data format.

— from Schema Generator

Where do I upload robots.txt?

Place it in the root of your website (e.g., example.com/robots.txt).

— from Robots.txt Generator

How many URLs can I include?

There's no hard limit, but keep sitemaps under 50,000 URLs or 50MB.

— from Sitemap Generator

How does the algorithm work?

It scores sentences based on word frequency maps after filtering out common stop words, highlighting key sentences.

— from Text Summarizer

Is it safe to paste private documents?

Yes. Processing is completely secure and local in your browser. Nothing is uploaded to any server.

— from Text Summarizer

What is this used for?

SEO managers and PPC advertisers use word combiners to quickly generate keyword lists (e.g. for Google Ads campaigns).

— from Word Combiner

Which languages are supported?

This version supports English text extraction. Make sure characters are clear and well-lit.

— from Image to Text (OCR) Converter

How does OCR work in-browser?

We load Tesseract.js (the WebAssembly compiled OCR engine) directly inside your browser so it runs locally.

— from Image to Text (OCR) Converter

Does it validate emails?

It checks syntax using regular expression matching to ensure it extracts active-style addresses.

— from Lead Email Extractor

Why should I rewrite my URLs?

Search engines prefer short, directory-structured paths over messy query parameters.

— from SEO URL Rewriter

What is Bionic Reading?

Bionic Reading boldens the first parts of words, allowing the brain to recognize words faster and speed up reading comprehension.

— from Bionic Reading Converter

What are the WCAG contrast ratio requirements?

WCAG 2.1 Level AA requires a minimum contrast ratio of 4.5:1 for normal-sized text and 3:1 for large text (18pt or 14pt bold). Level AAA (enhanced) requires 7:1 for normal text and 4.5:1 for large text. Most websites target AA compliance as the legal and industry standard.

— from Contrast Checker

What is a good contrast ratio for accessibility?

A contrast ratio of 4.5:1 or higher passes WCAG AA for body text — the standard required by most accessibility laws (ADA, EN 301 549, AODA). For decorative text, icons, or disabled UI elements, contrast requirements do not apply. Aim for 7:1 or higher (AAA) for the best readability for users with low vision.

— from Contrast Checker

How is color contrast ratio calculated?

The contrast ratio is calculated using the WCAG relative luminance formula. Each colour's RGB values are converted to linear light values, then combined into a single luminance number. The ratio is expressed as L1+0.05 / L2+0.05 where L1 is the lighter colour. A ratio of 1:1 means identical colours; 21:1 is maximum contrast (black on white).

— from Contrast Checker

Does color contrast affect SEO?

Not directly as a ranking factor, but poor contrast hurts accessibility scores, increases bounce rates (users leave unreadable pages faster), and may affect Core Web Vitals through engagement metrics. Additionally, failing accessibility guidelines can expose businesses to legal risk under ADA and similar legislation.

— from Contrast Checker

What does the auditor check?

It checks for missing alt text, heading hierarchy, ARIA attributes, form labels, and link text quality.

— from Accessibility Auditor

What readability scores are calculated?

Flesch Reading Ease, Flesch-Kincaid Grade Level, Gunning Fog Index, and text statistics.

— from Readability Checker

Is my JSON sent to a server?

No. All formatting happens locally in your browser.

— from JSON Formatter

Can it auto-detect the input format?

Yes. If the input starts with a JSON bracket '[' or '{', it converts JSON to CSV. Otherwise, it defaults to CSV to JSON.

— from CSV to JSON & JSON to CSV

Does it support custom quotes and commas?

Yes, our parser is RFC 4180 compliant, meaning it handles comma separators, newlines inside quoted fields, and escaped double quotes.

— from CSV to JSON & JSON to CSV

How does it handle nested objects?

It recursively parses child objects and defines them as sub-interfaces, using their key names for interface naming.

— from JSON to TypeScript Converter

Does it support arrays?

Yes. It inspects array elements to deduce their types and builds standard array notations like string[] or custom interface arrays.

— from JSON to TypeScript Converter

Is my JWT sent to a server?

No. Decoding is done entirely in your browser.

— from JWT Decoder

Can I verify JWT signatures?

We decode the payload and header but do not verify signatures in-browser.

— from JWT Decoder

Which algorithm should I use?

SHA-256 is recommended for most use cases. MD5 and SHA-1 are considered weak for security.

— from Hash Generator

How secure is this generator?

It is cryptographically secure. It uses the browser's native Cryptography API (window.crypto), which generates true, unpredictable random values.

— from Strong Password Generator

What is entropy?

Entropy measures the randomness and strength of a password in bits. Higher entropy makes the password exponentially harder for brute-force attacks to crack.

— from Strong Password Generator

How does the Age Calculator work?

It performs exact calendar calculations relative to the current year/month lengths to provide accurate years, months, and days breakdowns.

— from Age Calculator

Does it count leap years?

Yes, standard Date objects automatically handle the extra days in leap years.

— from Age Calculator

What values does the Time Duration Calculator add?

It allows you to enter two duration segments in days, hours, minutes, and seconds and add or subtract them. Or, use the List Accumulator mode to sum multiple timecards/tracks.

— from Time Duration Calculator

How does the List Accumulator parse items?

It supports standard formats like HH:MM:SS, MM:SS, as well as text keywords like 'd', 'h', 'm', 's', 'day', 'hours', 'minutes', 'seconds'.

— from Time Duration Calculator

What date formats are supported?

Any standard date strings (e.g. YYYY-MM-DD, MM/DD/YYYY) are supported.

— from Date & Time Calculator

Can I subtract weeks?

Yes, you can input the equivalent number of days (e.g. 7 days for 1 week) to add or subtract.

— from Date & Time Calculator

Is daylight saving time handled?

Yes, browser Intl APIs automatically resolve DST shifts depending on the date selected.

— from Time Zone Converter

What platforms are previewed?

Facebook, Twitter/X, and LinkedIn-style previews are shown.

— from Social Preview Tool

How does this work?

We fetch the URL and parse its Open Graph meta tags to render a preview.

— from Open Graph Preview

Can I use this for my website?

Yes. Our server fetches the URL metadata and returns a preview card you can embed.

— from Link Preview

Is it secure to decode tokens here?

Yes. Processing is completely local inside your browser.

— from Base64 Converter

Why use Base64 images?

Encoding small images directly as Base64 strings (Data URIs) lets you embed them directly in HTML/CSS. This reduces the number of HTTP requests your site makes, improving load times.

— from Base64 Image Encoder / Decoder

What formats can be decoded?

You can paste a raw base64 string or a full data URI scheme (e.g. data:image/png;base64,...). The decoder automatically detects the format and allows downloading it.

— from Base64 Image Encoder / Decoder

Why encode URLs?

URL encoding converts unsafe ASCII characters to % representation.

— from URL Encoder/Decoder

How does Sentence Case work?

It capitalizes the first letter of each sentence and lowercases the rest of the text.

— from Text Case Converter

What are camelCase, snake_case, and kebab-case used for?

These are standard naming conventions in programming. Developers use camelCase for variables, snake_case for database fields, and kebab-case for URL slugs and CSS classes.

— from Text Case Converter

What is UUID v7?

UUID v7 embeds a timestamp in the first 48 bits, allowing them to be sorted chronologically.

— from UUID Generator

How does it check differences?

It runs a line-by-line Longest Common Subsequence (LCS) comparison.

— from Text Diff Checker

What is Unix Epoch?

It is the number of seconds that have elapsed since January 1, 1970.

— from Epoch Date Converter

Does it support group matching?

Yes, any sub-group captures will be rendered in the match table output.

— from RegEx Tester

What dialects are supported?

It supports standard SQL formatting keywords (PostgreSQL, MySQL, SQLite).

— from SQL Formatter

How many fields does it support?

It supports the standard 5 fields: Minute, Hour, Day of Month, Month, Day of Week.

— from Cron Parser

How does the audio work?

It uses the Web Audio API to create a real-time oscillator inside your browser, so no sound file downloads are needed.

— from Morse Code Translator

Why use Hangul Filler?

Some games and chat applications block spaces or empty names. The Hangul Filler character appears blank but passes validation.

— from Invisible Character Generator

Can I simulate any site?

Yes, provided the site does not block iframe embedding using anti-clickjacking headers.

— from Responsive Screen Simulator

What is Chmod?

Chmod is a Unix command used to set file system permissions of files and directories (read, write, execute).

— from Unix Permissions Calculator

What do the numbers mean?

Read = 4, Write = 2, Execute = 1. The three octal digits represent Owner, Group, and Public scopes respectively.

— from Unix Permissions Calculator

Can it handle URLs without protocol?

Yes, the parser automatically prepends 'https://' if no protocol is found.

— from URL Parser & Query Splitter

Is this safe to run?

Yes, the parsing occurs entirely locally in your browser using standard JavaScript URL objects. No URL data is sent to any server.

— from URL Parser & Query Splitter

How does Auto Detect work?

If the input starts with '<', it parses as XML to JSON. If it starts with '{' or '[', it parses as JSON to XML.

— from JSON / XML Converter

Are attributes preserved in XML to JSON?

Yes, XML element attributes are converted to a nested '_attributes' object in the JSON output.

— from JSON / XML Converter

Will it format nested media queries?

Yes, it preserves blocks and nested rules while applying consistent indentation.

— from CSS Formatter & Minifier

Does minification remove comments?

Yes, all CSS comments (/* ... */) are removed during minification to minimize file size.

— from CSS Formatter & Minifier

Can I copy individual colors?

Yes, clicking the hex code inside the generated blocks will copy it to your clipboard.

— from Color Palette Generator

How do I find Hex color codes?

You can click the color picker icon to use a visual selector, type in manual hex values, or reference the popular color charts (Material Design, Flat, and Astral palettes) displayed in the output section.

— from Color Palette Generator

What do Hex, RGB, and HSL mean?

Hex is a hexadecimal representation of Red, Green, and Blue (#RRGGBB). RGB defines red, green, and blue intensities on a scale of 0 to 255. HSL defines color by Hue (color type on a 360-degree wheel), Saturation (vibrancy, 0% to 100%), and Lightness (brightness, 0% to 100%).

— from Color Palette Generator

What sizes are outputted?

We output standard 16x16, 32x32, and 192x192 PNG sizes for web app icons.

— from Favicon Generator

Does it support custom colors?

Yes, you can write any hex, rgb, or rgba color value in the text input.

— from CSS Shadow Generator

What is Glassmorphism?

Glassmorphism is a modern UI design trend that mimics a frosted glass look. It features translucent backgrounds with a subtle border and a backdrop blur effect.

— from CSS Glassmorphism Generator

Does it support older browsers?

Modern browsers (Chrome, Safari, Edge, Firefox) fully support the backdrop-filter property. For older browsers, it gracefully degrades to a simple translucent background.

— from CSS Glassmorphism Generator

What viewport is used?

The path is drawn inside a standard 100x100 relative SVG coordinate viewport.

— from SVG Path Visualizer

Are common stop words included?

No, density percentages filter out common stop words like 'the', 'is', 'and'.

— from Word & Density Counter

Which characters are converted?

It encodes &, <, >, ", ', and ` to their corresponding HTML entities.

— from HTML Entity Converter

Where do I get my User Agent?

By default, the tool will populate with your own browser's active User Agent header.

— from User-Agent Parser

Is code formatting supported?

Yes, block code (```) and inline code (`) are parsed into styled elements.

— from Markdown Converter

How does the Font Style Generator work?

It maps standard alphanumeric characters to their stylized mathematical and symbolic equivalents within the Unicode standard. This allows the styled text to be copied and pasted anywhere.

— from Font Style Generator

Will these fonts display correctly on all devices?

Most modern mobile and desktop operating systems support Unicode font characters. However, some older browsers or systems may render them as blank squares (tofu) if the font glyphs are not installed.

— from Font Style Generator

Are these characters readable by screen readers?

No. Since these utilize mathematical alphanumeric symbols, screen readers will interpret them letter-by-letter as mathematical characters rather than standard English words. We recommend using them for highlights and decorative text only, not for long-form content.

— from Font Style Generator

What binary standard does the text translator use?

It maps standard text characters to their respective UTF-8 character codes (binary representation) padded to 8 bits.

— from Binary & Base Converter

Can I convert high-precision numbers?

Yes, standard integer parsing handles normal and large numbers easily local inside the browser sandbox.

— from Binary & Base Converter

Is this query cached?

No, we perform direct query lookups to Cloudflare DNS endpoints so it fetches live values.

— from DNS Record Lookup

Why check CNAME records?

CNAME maps alias names to real domain targets, useful to verify CDN mappings.

— from DNS Record Lookup

What database does this tool query?

It queries standard, IANA-approved RDAP database records to fetch ownership status.

— from Whois Lookup

Is my personal IP address logged or stored?

The lookup is sent directly from your browser to IPAPI, the geolocation provider. Nexifr does not receive or store the IP address you submit — only the provider processes it to return the result.

— from IP Geolocation & ASN Checker

Is IP geolocation accurate?

IP geolocation is an estimate, not a precise location. It typically identifies the country reliably, the region in most cases, and an approximate city for fixed-line connections. Mobile carriers, VPNs, corporate proxies, and CDN edge nodes commonly cause results to reflect a network exchange point rather than a user's actual location.

— from IP Geolocation & ASN Checker

What is an ASN (Autonomous System Number)?

An ASN is a unique identifier assigned to a network operator — such as an ISP, hosting company, university, or corporation — that routes internet traffic. Knowing an IP's ASN tells you which organisation controls that network block, which is useful for diagnosing routing issues or identifying CDN and cloud provider addresses.

— from IP Geolocation & ASN Checker

Can I look up my own IP address?

Yes. Leave the IP Address field blank and click Run. The tool will detect and geolocate your current public IP address automatically.

— from IP Geolocation & ASN Checker

Does this upload my HTML code?

No. The formatting runs 100% locally in your browser.

— from HTML Beautifier & Minifier

What is domain age and how is it calculated?

Domain age is the total time elapsed since a domain name was first registered with an accredited domain registrar. Our tool queries public RDAP (Registration Data Access Protocol) servers to find the official registration event timestamp, then calculates the precise difference in years, months, and days from that date to today.

— from Domain Age Checker

How do I check the age of a domain name?

Simply enter the domain name (e.g. wikipedia.org) into the input field above and click Run. The tool instantly fetches and displays the registration date, expiration date, and the exact domain age in years, months, and days — no signup, no fees, no installation required.

— from Domain Age Checker

Why is domain age important for SEO?

A domain's registration date is useful context when researching a site, buying a domain, or reviewing its public history. It is not a reliable standalone Google ranking factor: content quality, relevance, links, usability, and technical accessibility matter far more.

— from Domain Age Checker

Can I check domain age for free?

Yes — Nexifr's domain age checker tool is completely free. There is no registration, no subscription, and no limit on the number of domains you can check. All queries are made directly from your browser using public RDAP endpoints.

— from Domain Age Checker

Is this the same as a WHOIS domain age check?

Functionally yes, but our tool uses the modern RDAP protocol instead of the legacy WHOIS system. RDAP returns structured JSON data, making it faster and more reliable than parsing WHOIS text output. Both methods ultimately retrieve the domain's creation date from the same registrar records.

— from Domain Age Checker

What domains can I check the age of?

You can check the age of virtually any registered domain including .com, .net, .org, .io, country-code TLDs (like .de, .uk, .in), and most modern TLDs. Domains must be registered and publicly visible in RDAP databases. Private or reserved domains may not return full registration data.

— from Domain Age Checker

How many redirects can this follow?

It follows up to 10 redirects, preventing circular redirect loops.

— from HTTP Redirect Tracer

Why should I check my SSL certificate?

Web browsers flag expired or invalid SSL certificates as insecure — displaying a full-page 'Your connection is not private' warning that causes visitors to immediately leave. Checking your SSL certificate status helps you renew before expiry, verify correct domain matching, and ensure browsers and search engines trust your site.

— from SSL Certificate Checker

How do I check if an SSL certificate is valid?

Enter your domain name (e.g. github.com) in the field above and click Run. The tool connects to your server and retrieves the certificate details including the issuer, expiration date, remaining days, and whether the domain name matches the certificate's Common Name (CN) or Subject Alternative Name (SAN) — all in under a second.

— from SSL Certificate Checker

What is an SSL certificate checker tool?

An SSL certificate checker is a tool that connects to a web server and reads its TLS certificate details without a browser. It reveals expiration dates, the Certificate Authority (CA) that issued it, the number of days remaining before renewal is required, and whether the certificate is properly configured for the queried domain.

— from SSL Certificate Checker

How often should I check SSL certificates?

Best practice is to check your SSL certificates at least once a month, and set up automated renewal alerts 30 and 7 days before expiry. Free certificates from Let's Encrypt expire every 90 days — missing renewal causes your site to become inaccessible to all browsers.

— from SSL Certificate Checker

Does HTTPS affect Google search rankings?

Yes. Google confirmed HTTPS as a ranking signal in 2014. Sites without a valid SSL certificate may rank lower than equivalent HTTPS sites. Beyond rankings, browsers like Chrome actively warn users about non-HTTPS pages, dramatically increasing bounce rates and reducing time-on-site signals.

— from SSL Certificate Checker

Is my text data private?

We query LanguageTool API. No data is stored, and check requests are deleted immediately after parsing.

— from Spelling & Grammar Checker

How does the list shuffler randomise lines?

We implement the Fisher-Yates shuffle algorithm client-side to guarantee completely unbiased randomness.

— from List Shuffler

Is my text data saved on the server?

No, all sorting, shuffling, and parsing occur locally in your browser sandbox, keeping your list data completely private.

— from List Shuffler

Does this tool upload my images?

Never. The canvas processing works 100% offline in your browser, bypassing any server transfers to secure your photos.

— from Image Color Inverter

Can I invert transparent PNG files?

Yes, inverting transparent PNGs will preserve the transparency layer.

— from Image Color Inverter

Is this number generator secure?

Yes, it leverages the browser's cryptographically secure window.crypto.getRandomValues API instead of Math.random.

— from Random Number Generator

How many numbers can I generate at once?

You can generate up to 10,000 numbers at once, either with or without duplicate selection.

— from Random Number Generator

Can I use more than two colors?

Yes, just add more hex values separated by commas.

— from CSS Gradient Generator

Does this support rgb to hex?

Enter any hex color and see its RGB and HSL equivalents.

— from Color Picker & Converter

What does inset do?

Inset places the shadow inside the element instead of outside.

— from Box Shadow Generator

What is a CSS flexbox generator?

A CSS flexbox generator is a visual tool that lets you configure flexbox layout properties — direction, wrapping, alignment, justification, and gap — through simple dropdowns, then automatically outputs the corresponding CSS code. It removes the need to memorise flexbox property names and values, making it far faster to build responsive web layouts.

— from CSS Flexbox Generator

Does this generate responsive code?

The tool generates a complete, copy-ready CSS flexbox declaration. For full responsiveness, wrap the output in media queries (e.g. @media (max-width: 768px)) to adjust the flex direction or alignment at different screen sizes. Most developers start with a row layout on desktop and switch to column on mobile.

— from CSS Flexbox Generator

What is the difference between justify-content and align-items?

justify-content controls how flex items are distributed along the main axis (horizontal in a row layout). align-items controls how items are aligned along the cross axis (vertical in a row layout). For example, justify-content: space-between spreads items horizontally, while align-items: center vertically centres them within the container.

— from CSS Flexbox Generator

When should I use flexbox vs CSS Grid?

Use Flexbox when you are laying out items in a single direction — either a row or a column. It excels at navigation bars, button groups, and centering content. Use CSS Grid when you need a two-dimensional layout with explicit rows and columns, such as a full page layout or a card grid.

— from CSS Flexbox Generator

Is the generated CSS compatible with all browsers?

Yes. CSS Flexbox has been supported in all modern browsers (Chrome, Firefox, Safari, Edge) since 2015 and has over 99% global browser support. The generated code uses standard, unprefixed flexbox properties that work universally without any polyfills.

— from CSS Flexbox Generator

What do these types mean?

Protanopia is red-blind, deuteranopia is green-blind (most common), and tritanopia is blue-blind.

— from Color Blindness Simulator

Is this secure?

Yes, it uses AES-256-GCM with PBKDF2 key derivation, all in your browser. Nothing is sent to a server.

— from Text Encrypt / Decrypt

Can I decrypt messages from other tools?

As long as the same password and algorithm are used, yes.

— from Text Encrypt / Decrypt

Does this validate YAML?

It formats existing YAML. For validation, check with a YAML linter.

— from YAML Formatter

Can I decrypt or verify JWTs too?

Use the existing JWT Decoder tool in Developer Studio for verification. This tool generates new JWTs.

— from JWT Generator & Debugger

What formats does it generate?

It generates standard CSS background values.

— from CSS Gradient Generator

Can I copy individual formats?

Yes, you can copy Hex, RGB, HSL, or CMYK representations.

— from Color Picker & Converter

Does it support decimal percentages?

Yes, all calculations handle decimal numbers with high precision.

— from Percentage Calculator

How many units are supported?

Over 50 units across 7 physical categories are supported.

— from Unit Converter

What is a healthy BMI?

A healthy BMI is typically defined between 18.5 and 24.9.

— from BMI Calculator

What is an amortization schedule?

It is a table showing each monthly payment breakdown into principal and interest.

— from Loan & EMI Calculator

Can I split the bill evenly?

Yes, the calculator automatically splits both the tip and total bill among the specified number of people.

— from Tip Calculator

What is the standard aspect ratio?

16:9 is the standard for widescreen video, while 4:3 is standard for older media.

— from Aspect Ratio Calculator

What is the Pomodoro technique?

A time management method using 25-minute focus intervals followed by 5-minute short breaks.

— from Pomodoro Timer

Is my password sent to a server?

No, the verification happens entirely in your browser using local regex check rules.

— from Password Strength Checker

Where do the names come from?

They are generated from a localized database of popular cultural first and last names.

— from Random Name Generator

What are 4xx errors?

They indicate client-side errors, such as requesting a page that does not exist (404).

— from HTTP Status Code Reference

What is cURL?

A command-line tool for transferring data with URLs, widely used to test APIs.

— from cURL Command Builder

Does my text leave the device?

No, synthesis is computed natively by your browser's Web Speech API.

— from Text to Speech (TTS)

Which browsers support speech to text online?

Google Chrome and Microsoft Edge have the most complete support for the Web Speech API used by this tool. Safari on macOS and iOS also supports speech recognition. Firefox has limited or no support — if you are on Firefox, switch to Chrome for the best experience.

— from Speech to Text (STT)

Does microphone audio leave my device?

Speech recognition is processed by your browser and its underlying recognition provider (for example, Google's speech API in Chrome). Audio is typically sent to that provider's service to generate the transcript — it does not pass through Nexifr's servers. Do not dictate passwords, financial data, health information, or other sensitive content.

— from Speech to Text (STT)

What languages does this speech to text tool support?

This tool currently supports English (US), Spanish (ES), French (FR), and German (DE). Select the language that best matches the speaker before you start recording. Mixing languages within a single session reduces accuracy significantly.

— from Speech to Text (STT)

Is this speech to text tool free to use?

Yes. The tool is completely free — there is no character limit, no session cap, and no account required. Recognition is performed by your browser using the Web Speech API, so the only requirement is a working microphone and a supported browser.

— from Speech to Text (STT)

Does it support transparent watermarks?

Yes, you can adjust the opacity value down to make it semi-transparent.

— from Image Watermark Generator

How does it extract colors?

It runs a fast K-means clustering algorithm directly on the sampled image pixels.

— from Image Color Extractor

How do I convert a video to GIF online for free?

Upload your MP4, WebM, or MOV file to Nexifr's Video to GIF Converter. Set the start and end time to clip only the part you need, choose your preferred FPS and width, then click Convert. Your GIF is generated server-side using FFmpeg and downloaded directly to your device — no account or watermark required.

— from Video to GIF Converter

What is the best FPS for a GIF?

10–15 FPS is the sweet spot for most animated GIFs. It produces smooth enough motion while keeping file sizes manageable. Use 5 FPS for slideshows or text-heavy clips, and 20–24 FPS for fast-moving content like sports or gaming highlights.

— from Video to GIF Converter

How large can my video file be?

Nexifr supports video files up to 50 MB. For the best GIF results, we recommend converting short clips of 3–15 seconds — longer clips produce very large GIF files. Use the Start Time and End Time fields to select only the segment you need.

— from Video to GIF Converter

Why does my GIF look different from the original video?

GIFs are limited to 256 colours per frame, while video supports millions. Nexifr uses FFmpeg's palettegen and paletteuse filters with Bayer dithering and lanczos scaling to maximise colour fidelity, but some colour banding is inherent to the GIF format. Lowering the output width or FPS can also improve colour quality.

— from Video to GIF Converter

What video formats can I convert to GIF?

Nexifr supports MP4 (H.264/H.265), WebM (VP8/VP9), MOV (QuickTime), and OGG video. MP4 is recommended for the best compatibility and conversion speed.

— from Video to GIF Converter

Can I search or filter the CSV data?

Yes, the viewer includes a dynamic live filter search and column sorting.

— from CSV Viewer & JSON Exporter

Where is my image processed?

It is securely processed on our servers using Nexifr AI and deleted from our server after 5 minutes.

— from AI Background Remover

Does it auto-detect input formats?

Yes, it automatically parses JSON, YAML, or TOML based on structure syntax.

— from YAML / JSON / TOML Converter

Which JSON Schema drafts are supported?

This validator supports JSON Schema Draft 4, Draft 7, and Draft 2020-12 — the three most widely used versions. The schema is compiled using Ajv (Another JSON Validator), the most widely adopted JSON Schema implementation for JavaScript. The correct draft is detected automatically from the $schema field in your schema definition.

— from JSON Schema Validator

What is the difference between a JSON syntax error and a schema validation error?

A syntax error means the JSON text itself is malformed and cannot be parsed — caused by a missing quote, misplaced comma, or unclosed bracket. A schema validation error means the JSON is structurally valid text but does not conform to the rules defined in the schema, such as a missing required field, wrong data type, or value outside a defined enum. Fix syntax errors first; once the JSON parses cleanly, address schema validation errors.

— from JSON Schema Validator

What is AJV (Another JSON Validator)?

Ajv is the most widely adopted JSON Schema validator for JavaScript. It compiles schemas into optimised validation functions for high performance, supports all major JSON Schema drafts, and produces detailed error messages that identify exactly which property failed and why. This tool uses Ajv compiled and run entirely in your browser — no server is involved.

— from JSON Schema Validator

Is it safe to paste my JSON data into this validator?

Validation runs entirely in your browser using Ajv — no data is sent to any server. Even so, use redacted or anonymised test data rather than production credentials, API keys, personal information, or secrets when testing schemas in any browser-based tool.

— from JSON Schema Validator

Does it break functional script logic?

No, it strips spacing and comments safely without altering symbols or syntax structures.

— from JavaScript Minifier

Can I add multiple images?

Yes, you can upload multiple images to convert them into a multi-page PDF.

— from Image to PDF Converter

How do I define ranges?

Use hyphens for ranges (e.g. 1-4) and commas for separate pages (e.g. 1-3, 6).

— from Split PDF

What is the difference between JSON and YAML?

JSON uses braces and brackets with quoted keys; YAML uses indentation and colons. YAML is more human-readable for configuration files.

— from JSON to YAML Converter

Can this convert YAML to JSON?

Yes — just select 'YAML → JSON' in the direction dropdown.

— from JSON to YAML Converter

Does it validate my JSON?

Yes. If the JSON is malformed, you will see a syntax error message before conversion.

— from JSON to YAML Converter

How do I find the discount percentage?

Select the second mode, enter the original and final prices, and the tool calculates the discount % and savings amount automatically.

— from Discount Calculator

Can I find the original price from a discounted price?

Yes — use the third mode. Enter what you paid and the discount percentage, and get the original price back.

— from Discount Calculator

Does this work for any currency?

Yes — the calculator works with any currency. Just treat the symbol as irrelevant; only the numbers matter.

— from Discount Calculator

How much is $25/hour annually?

At $25/hour and 40 hours/week for 52 weeks, your annual salary is $52,000.

— from Salary Calculator

Does the tax estimate include state taxes?

No — only US federal income tax is estimated. It excludes state taxes, FICA (Social Security/Medicare), and deductions. Consult a tax professional for accurate figures.

— from Salary Calculator

Can I use this for non-US salaries?

Yes — the salary conversion rates work globally. The tax estimate is US-specific and can be ignored for other countries.

— from Salary Calculator

How do I create a pill-shaped button?

Set all four corners to 50% or a very large px value (like 9999px). Use the 'Pill' preset for one click.

— from Border Radius Generator

What is the CSS shorthand order for border-radius?

The four values go: top-left, top-right, bottom-right, bottom-left — clockwise from the top-left.

— from Border Radius Generator

Does it generate Tailwind classes?

Yes — for standard px values that match Tailwind's scale, the equivalent Tailwind class is shown alongside the CSS.

— from Border Radius Generator

What are UTM parameters?

UTM parameters are tags added to URLs that tell Google Analytics where traffic came from (source), how it arrived (medium), and which campaign drove it.

— from UTM Builder

Which UTM parameters are required for GA4?

utm_source, utm_medium, and utm_campaign are required. utm_term and utm_content are optional but useful for paid search and A/B test attribution.

— from UTM Builder

Can I decode an existing UTM URL?

Yes — select 'Decode UTM URL', paste any URL, and the tool parses and displays all UTM parameters clearly.

— from UTM Builder

What is compound interest?

Compound interest means you earn interest on both your principal and the interest already earned. Over time this creates exponential growth — 'interest on interest'.

— from Compound Interest Calculator

What does compounding frequency mean?

More frequent compounding means interest is calculated and added to your balance more often. Daily compounding yields slightly more than annual compounding at the same rate.

— from Compound Interest Calculator

Can I include regular contributions?

Yes — enter a monthly contribution amount. The calculator adds this to each period's calculation and shows total principal vs total interest earned.

— from Compound Interest Calculator

What is included in PITI?

PITI stands for Principal, Interest, Taxes, and Insurance — the four components of a full monthly mortgage payment. Enter property tax and insurance to see your full PITI.

— from Mortgage Calculator

What is PMI and when do I need it?

Private Mortgage Insurance (PMI) is required when your down payment is less than 20%. It adds 0.5–1.5% of the loan per year. The calculator warns you if your down payment triggers PMI.

— from Mortgage Calculator

How does loan term affect my payment?

A 15-year term has higher monthly payments but significantly less total interest. A 30-year term reduces monthly payments but can double the total interest paid.

— from Mortgage Calculator

How many pages can I convert?

Up to 20 pages per conversion. For larger PDFs, you can use Split PDF first to extract the pages you need.

— from PDF to PNG Converter

What resolution are the output PNGs?

At 2× scale (the default), output is 144 DPI — ideal for digital use. At 3×, you get ~216 DPI for print-quality output.

— from PDF to PNG Converter

Is my PDF file sent to a server?

No. PDF rendering uses PDF.js loaded in your browser. Your file never leaves your device.

— from PDF to PNG Converter

How do I save as PDF?

The tool opens your browser's print dialog. Select 'Save as PDF' as the destination (available in Chrome, Edge, Firefox, and Safari).

— from Markdown to PDF

Are code blocks styled?

Yes — code blocks have a dark background and monospace font. Enable 'Background graphics' in Chrome's print settings for best results.

— from Markdown to PDF

Can I convert GitHub README files?

Yes — paste the README content directly. Markdown tables, headings, lists, and code blocks are all supported.

— from Markdown to PDF

What image formats can I use as frames?

PNG, JPG, WebP, and most other browser-supported image formats. HEIC requires conversion first.

— from GIF Maker

Is there a frame limit?

Maximum 20 frames for browser-based encoding. For longer animations, consider splitting into multiple GIFs.

— from GIF Maker

How do I control animation speed?

Set the 'Frame Duration' in milliseconds — 100ms for fast, 500ms for normal, 1000ms+ for slow animations.

— from GIF Maker

What does 'auto' do for timestamps?

Auto captures 5 frames at 0%, 25%, 50%, 75%, and 100% of the video duration — perfect for a quick overview of any video.

— from Video Screenshot Extractor

Is there a limit on frame count?

You can extract up to 20 frames per run. Enter timestamps as comma-separated seconds (e.g. 0, 5, 10, 30).

— from Video Screenshot Extractor

What are US passport photo requirements?

US passport photos must be 2×2 inches (51×51mm), with a white or off-white background, taken within the last 6 months. The face must cover 70–80% of the frame.