Developers
JSON and SQL formatters, Base64, URL encoding, UUID, hashes, JWT, regex, CRON, WCAG contrast checker and Unix timestamps.
13 tools
JSON formatterPaste JSON to beautify or minify it instantly. If it is invalid, you get the exact line and column, a code excerpt with a caret and a plain-language explanation.Password generatorCreate secure passwords from letters, digits and symbols, or easy-to-type passphrases made of random English words. Every password is generated in your browser with crypto.getRandomValues() and never leaves your device.Base64 encoder and decoderConvert text to Base64 and back with proper UTF-8 handling, so accented letters, non-Latin scripts and emoji survive the round trip. The URL-safe variant used in JWTs and URLs is supported too.Contrast checkerEnter a text and a background colour (HEX, RGB or HSL) to get the contrast ratio instantly, see whether the pair meets WCAG 2.2 AA and AAA, and get the closest colour that passes.Cron generatorEnter a cron expression to see what it means and when it will run next - or build a schedule in the visual builder and pick from common presets.CSV ↔ JSON converterPaste data or load a file: the converter detects the delimiter (comma, semicolon, tab or pipe), handles quoted fields correctly and produces a file that opens cleanly in Excel or Google Sheets.Hash generator (MD5, SHA-256)Type text or drop a file to get all common hashes at once. Paste the checksum published by a vendor to verify that your download is intact - the file is hashed locally and never uploaded.JWT decoderPaste a JWT to see its header and claims in a readable form, check whether it has expired, and verify the signature with a secret or public key. Everything runs locally.Regex testerType a pattern and a test string to see every match highlighted, with a table of capture groups and a live replace preview. Matching runs in a Web Worker with a time limit, so a runaway pattern never freezes the page.SQL formatterPaste an SQL query to beautify it instantly - each clause on its own line, consistent indentation and keyword case - or minify it to a single line. Supports over a dozen dialects.Unix timestamp converterSee the current epoch time ticking live, paste any timestamp to get the date in your time zone, UTC, ISO 8601 and HTTP format, or pick a date to get its timestamp in seconds and milliseconds.URL encoder and decoderPercent-encode query values or whole addresses, decode %XX sequences back to readable text, and break a URL into its parts with a table of query parameters. Everything runs in your browser.UUID generator (v4, v7)Create UUIDs with a cryptographic random generator, copy them or download a .txt file, and paste any UUID or GUID into the validator to see its version, variant and creation time.
Developer tools that keep your data local
Tokens, API keys and production data should not be pasted into random websites. Here everything - from decoding JWTs to formatting SQL - happens in your browser. Format and validate JSON, convert CSV to JSON, encode Base64 and URLs, generate hashes, UUIDs, passwords and CRON expressions, test regular expressions, convert Unix timestamps and check WCAG colour contrast.