💻 Developer Tools
Developer tools cover the everyday text and data chores of working with code: regular expressions, base64 and URL encoding, JSON and CSV conversion, HTML/CSS/JS minification, hashing, UUID and password generation, case conversion, diffing and slug generation. Each tool documents the algorithm it implements, with examples you can paste straight into your own work. The implementations follow the relevant standards, including RFCs and the WHATWG specs, and the pages note the edge cases that matter, such as how a character set is handled or whether a hash is salted. Everything runs locally in your browser, so the data you process never leaves your machine. The pages are written for working developers: the algorithms are named, the standards are cited, and the edge cases that commonly bite are called out in the FAQ.
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AI Text Summariser
Summarise any text in seconds with AI.
AI Grammar Checker
Fix grammar, spelling, and style errors instantly.
AI Paraphraser
Rewrite text in a different tone or style.
AI Translator
Translate text into 30+ languages instantly.
Word Counter
Count words, characters, sentences, and paragraphs.
Character Counter
Count characters with and without spaces.
Text Case Converter
Convert text to UPPER, lower, Title, or camelCase.
IPv4 Subnet Calculator
CIDR subnet calculator, network, broadcast, host range, mask and wildcard.
Regex Tester
Test regular expressions with live match highlighting.
Cron Expression Generator & Explainer
Parse any cron expression (5-field POSIX or 6-field Quartz) and see the next 10 to 20 fire times in your IANA timezone plus a plain-English description like "Runs at 09:30 on Monday".
Cron Expression Builder
Build and decode cron expressions with next-run times.
JSON Formatter
Format, validate, and minify JSON instantly.
Text Diff Tool
Compare two texts and highlight the differences.
JWT Decoder
Decode and inspect JSON Web Tokens instantly.
JWT Secret Generator
Generate cryptographically secure HMAC secrets for signing JWTs (HS256/HS384/HS512).
UUID Generator
Generate random UUID v4 identifiers instantly.
Hash Generator
Generate SHA-1, SHA-256, SHA-384, and SHA-512 hashes.
Text to Binary Converter
Convert text to binary, hex, or decimal and back.
URL Slug Generator
Convert any text into a clean URL-friendly slug.
Reading Time Estimator
How long to read any text at your pace.
Resistor Colour Code
Decode 4-band and 5-band resistor colour codes.
LED Resistor Calculator
Correct series resistor value for any LED circuit.
Morse Code Converter
Bidirectional text ⇄ Morse with audio playback and copy.
Contrast Ratio Checker
WCAG contrast ratio for any text and background colour.
Colour Palette Generator
Generate harmonious colour palettes from any base colour.
Random Colour Generator
Generate 1 to 50 random colours in HEX, RGB, or HSL with pastel, vibrant, or dark modes.
Invoice Number Generator
Generate sequential invoice numbers with custom prefix and padding.
Case Converter
Convert text between different capitalisation styles instantly.
Cron Expression Generator
cron expression generator.
CSS Minifier
Minify CSS files by removing whitespace, comments, and redundant code.
Find and Replace Tool
Find and replace text across any content, with support for plain text, case-sensitive ...
HTML Minifier
Minify HTML by removing whitespace, comments, and redundant attributes.
HTTP Status Code Reference
http status code reference.
JavaScript Minifier
Minify JavaScript files by removing whitespace, comments, and shortening variable names.
MD5 Hash Generator
Generate MD5 hash values for any text input.
Readability Score Checker
readability score checker.
Remove Duplicate Lines
Remove duplicate lines or values from any list of text.
Sentence Counter
Count sentences, words, characters, and paragraphs in any text.
SHA-256 Hash Generator
Generate SHA-256 hashes for any text or file.
Sort Lines Alphabetically
sort lines alphabetically.
Text Reverser
Reverse any text, flip entire strings, reverse words, or mirror individual letters.
Text to Slug Converter
Convert any title, phrase, or sentence into a clean URL slug.
Random Password Generator
Generate cryptographically secure random passwords with adjustable length, character classes, and ambiguous-character exclusion.
Markdown to HTML Converter
Convert Markdown to sanitised HTML with a live preview. GFM tables, fenced code and task lists; DOMPurify strips scripts and XSS.
Markdown Table Generator
Generate Markdown tables from CSV or a manual grid, with alignment and HTML export.
Capacitor Code Calculator
Decode and encode ceramic capacitor markings. 3-digit body code (104, 223, 471), tolerance letter (K, M, J…), n-notation (4n7), and R-notation (4R7). Shows pF, nF and µF.
HTML Entity Encoder & Decoder
Encode and decode HTML entities live. Named (& < ©), decimal (©), and hex (©) with full Unicode and emoji support.
Pixels to REM Converter
Convert CSS px to rem and back with a configurable root font size. Live px ⇄ rem, separate em panel, pt and %, common-px reference table, and root-font presets (16, 10, 14, 18, 20).
UTM Link Builder
Build tagged campaign URLs with utm_source, utm_medium, utm_campaign, utm_term, utm_content, and utm_id.
Video Bitrate Calculator
Compute file size from bitrate and duration, required bitrate from a target size, and upload/download time from connection speed. Includes a typical bitrate reference table by resolution.
Base64 Encoder / Decoder
Encode and decode Base64 with standard + URL-safe variants, padding toggle, and UTF-8 support.
Binary to Decimal Converter
Convert between binary, decimal, octal, and hexadecimal numbers with BigInt precision.
Gradient Generator
Design CSS linear, radial, and conic gradients with a live preview and copy-ready CSS.
Text to Morse Code Converter
Convert text to International Morse Code and decode Morse back to text. Includes a 600 Hz Web Audio playback tone.
Username Generator
Generate unique, memorable usernames with 4 patterns: word+digits, dice-style phrase, fantasy, and tech-handle.
SQL Formatter
Format and beautify SQL with dialect-aware keyword highlighting.
YAML to JSON Converter
Parse a YAML document and pretty-print it as JSON in your browser. Strict indentation handling, clear error messages, common-subset coverage.
URL Encoder / Decoder
Percent-encode and decode URLs and query parameters using encodeURIComponent, encodeURI, and their decoders. Includes a query-string parser.
ISBN Validator
Check ISBN-10 and ISBN-13 (Bookland / EAN-13) check digits and convert between formats, fully client-side.
.htaccess Generator
Generate Apache .htaccess rules with toggles for HTTPS, WWW, redirects, caching, compression, hotlink protection, and error pages.