A practical reference for digital utilities, file formats, encoding, security, timestamps, and other tool-focused calculations.
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Aspect ratio is the proportional relationship between the width and height of an image, video, or display screen, expressed as two colon-separated integers (such as 16:9 or 4:3).
Aspect Ratio = (Width / GCD) : (Height / GCD)Encode and decode text or files to Base64.
Case Converter converts text between title case, sentence case, camelCase, PascalCase, snake_case, kebab-case, and more.
Color Code Converter converts HEX, RGB, HSL, HSV, and CMYK.
Color Contrast Checker checks text and background color contrast against WCAG AA and AAA.
Visual cron schedule builder with human-readable descriptions and next run time previews.
CSV to JSON Converter converts CSV to JSON and JSON back to CSV in browser.
Diff Checker compares two texts and see differences highlighted line-by-line in side-by-side or unified view.
Favicon Generator generates all favicon sizes from an image or text.
Hash Generator generates MD5, SHA-1, SHA-256, and other hash digests for text or files, entirely in browser.
Reduce image file sizes with adjustable quality.
Image Format Converter converts JPEG, PNG, and WebP formats.
Image to PDF converts images to a multi-page PDF document.
Test download speed, upload speed, ping, and jitter.
Create professional invoices with line items, taxes, and discounts — download as PDF.
Format, validate, beautify, and minify JSON data in browser.
Decode a JWT's header, payload, and signature to inspect its claims, entirely in browser.
LLM API Cost estimates and compares LLM API costs across models — input, output, and cached tokens, with monthly and annual cost projections and prompt-caching savings.
Lorem Ipsum Generator generates placeholder text in classic Latin, hipster, tech, and office styles.
Write Markdown with live HTML preview, formatting toolbar, and export options.
Translate text to Morse code and back, with support for letters, numbers, and punctuation, plus an audio playback option.
Spell out a number in words, including currency (cheque) format and ordinal form, for any value up to the trillions.
Percentage calculator, random numbers, base converter, Roman numerals.
Password Generator generates strong, random passwords or passphrases with control over length, character sets, and real entropy.
Merge multiple PDF files into one document.
Extract specific pages or split a PDF into individual files.
Configurable Pomodoro focus timer with break intervals, notifications, and session statistics.
Privacy Policy Generator generates a customized privacy policy for website with GDPR and CCPA support.
PX to REM Converter converts pixels, rem, and em using chosen root font size, for CSS typography and sizing.
Pick one or more random items from a list — names, options, or entries — with or without repeats, for raffles and decisions.
Test regular expressions with real-time matching, capture groups, and replacements.
Preview any website at different screen sizes with preset device dimensions.
Screen PPI calculates screen's pixels per inch (PPI), dot pitch, and total pixels from its resolution and diagonal size, and compares display sharpness.
Turn any title or text into a clean URL slug — lowercase, hyphenated, accent-stripped — with separator and case options.
Format and beautify SQL queries with proper indentation and keyword casing, or minify them — entirely in browser.
Subnet calculates network address, broadcast address, subnet mask, and usable host count from an IP address and CIDR prefix.
Terms of Service Generator generates customized terms of service for websites, apps, and SaaS products.
Text to Binary Converter converts text to binary and back, plus decimal, hexadecimal, and ASCII codes, character by character.
Word count, case converter, finds & replace, line sorter.
Unix Timestamp Converter converts Unix timestamps to dates and back.
Encode or decode URLs and query strings using percent-encoding, with separate modes for a full URL or a single component.
Build trackable campaign URLs with UTM parameters for Google Analytics, with validation, lowercase enforcement, and a copyable link.
UUID Generator generates RFC 4122/9562 UUIDs in v1, v3, v4, v5, or v7 format, and decode any existing UUID's version and timestamp.
Video Bitrate & File Size calculates video file size from bitrate and duration, solving for bitrate to hit a target size, and calculates recommended bitrates for YouTube, Twitch, and more.