Free Online Developer Tools
JSON, Base64, JWT, regex, hashing and 24+ utilities that run 100% in your browser — fast, free, and private. Your data never leaves your device.
Base64 Encoder / Decoder
Encode text or files to Base64 — or decode Base64 back to text and binary files
EncodingURL Encoder / Decoder
Percent-encode special characters in a URL string, or decode an encoded URL back to plain text
EncodingJWT Decoder / Encoder
Decode and inspect JWT header, payload and expiry — or build and sign new tokens with HS256 / RS256
EncodingJSON Formatter
Beautify or minify JSON with configurable indent — validates syntax and highlights errors in real time
FormattersYAML ↔ JSON
Convert YAML to JSON or JSON to YAML instantly — all processing happens in the browser
FormattersMinify & Beautify
Minify or beautify JSON, CSS, HTML, and SQL — paste code and switch languages to reformat instantly
FormattersJSON ↔ CSV
Convert a JSON array to CSV or a CSV file to JSON — with a live table preview of the result
FormattersUUID Generator
Generate cryptographically random UUID v4 values in bulk — with uppercase and no-hyphen options
GeneratorsPassword Strength Checker / Generator
Generate strong random passwords with custom length and character sets — then check any password's crack time
GeneratorsLorem Ipsum Generator
Generate placeholder lorem ipsum text by words, sentences, or paragraphs — with a one-click regenerate
GeneratorsTimestamp Converter
Convert a Unix timestamp to a human-readable date — or convert any date string back to a Unix timestamp
ConvertersColor Converter
Convert colors between HEX, RGB, and HSL — pick with a color swatch or type any format to see the others
ConvertersCase Converter
Convert text between camelCase, PascalCase, snake_case, kebab-case, SCREAMING_SNAKE, dot.case, and more
ConvertersNumber Base Converter
Convert numbers between binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16)
ConvertersCron Explainer
Paste a cron expression to get a plain-English explanation — with a part-by-part breakdown and quick examples
ConvertersCrontab Builder
Visually build a cron expression using dropdowns and controls — see the expression update as you go
ConvertersCIDR Calculator
Calculate subnet ranges, network masks, broadcast address, and host count for any IPv4 or IPv6 CIDR block
NetworkHTTP Status Codes
Look up any HTTP status code — browse all codes with descriptions grouped by class, or search by number or keyword
NetworkURL Parser & Builder
Break a URL into protocol, hostname, port, path, query params, and fragment — then edit params and rebuild it
NetworkRegex Tester
Test regular expressions against a string with live match highlighting — toggle flags and see all matches instantly
TextText Diff
Paste two text blocks to see a side-by-side diff — added and removed lines are color-coded with a line count
TextKey Generator
Generate RSA-OAEP key pairs (2048 / 4096-bit) or AES-GCM secret keys (128 / 256-bit) using Web Crypto API
CryptographyHash Generator
Hash any text or file with SHA-1, SHA-256, SHA-384, or SHA-512 — all computed locally using Web Crypto
CryptographyEncrypt / Decrypt
Encrypt and decrypt text using RSA-OAEP (public/private key) or AES-GCM (symmetric key) — all in-browser via Web Crypto
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