Developer tools

JSON formatter, Base64, hashes, UUID, JWT, regex, cron, timestamps and colour tools

JSON formatterPaste JSON to pretty-print it, validate it with the exact error line, or minify it to one line. Base64 encode / decodeConvert text to Base64 and Base64 back to text — UTF-8 safe, with a URL-safe option. Image ↔ Base64Pick an image to get its Base64 data URL for HTML or CSS, or paste Base64 to view and save the image. URL encode / decodeEncode text for URLs (percent-encoding) and decode %E0%B8… links back into readable text. HTML entitiesTurn < > & " into &lt; &gt; &amp; to show code on a web page, and decode &#xxxx; back into characters. Hash generatorType text or pick a file to get MD5, SHA-1, SHA-256, SHA-384 and SHA-512 at once — e.g. to verify a download. UUID generatorGenerate unique IDs (UUID, ULID, NanoID) by the hundred with your browser's secure random generator. JWT decoderPaste a JWT to read its header and payload, see when it was issued and expires, and verify HS256 signatures. Regex testerType a regex and test text to see every match with its groups, and try replacements live. Cron generatorEnter a cron expression to get a plain-language description and its next 10 run times, or pick a common example. Unix timestamp converterSee the current Unix time, convert a timestamp (seconds or milliseconds) to a date, or a date to a timestamp. Code formatterPaste hard-to-read code to get it neatly indented, or minify it to make files smaller for production. Markdown previewType Markdown and see it rendered instantly, with the HTML ready to copy. Text ↔ binaryTurn text into binary, hexadecimal, octal or decimal codes per character, and decode them back (UTF-8 aware). Color converterEnter a colour in any format to get every format, light-to-dark shades and matching colours. Contrast checkerPick text and background colours to see whether they meet WCAG AA / AAA, with a suggested colour that passes. CSS gradientChoose colours, angle and gradient type to preview it instantly and copy the CSS. JSON to CSVPaste a JSON array to get a CSV table for Excel or Google Sheets — nested objects supported. CSV to JSONPaste CSV or cells copied from Excel to get JSON — the first row becomes field names and numbers are typed automatically. YAML ↔ JSONPaste YAML or JSON — it's detected and converted to the other format, with the error line if something's wrong. JSON to TypeScriptPaste sample JSON to get TypeScript interfaces or types, including nested objects and arrays. AES encryptionLock a message with a password using AES-256-GCM; the recipient decrypts it here with the same password. TOTP generatorCreate a two-factor secret, see the 6-digit code that changes every 30 seconds and a QR to scan in an authenticator app. Password strength checkerType a password to see its strength score, time to crack and tips — checked on your device, never sent. CSS box shadowAdjust offset, blur, spread, colour, opacity and inset with a live preview, and copy the CSS. CSS border radiusRound all four corners together or separately, make blob shapes, preview and copy the CSS. Tailwind colorsBrowse the full Tailwind palette, shades 50–950, copy class names, HEX or RGB, and find the closest Tailwind colour. Color palette generatorPick one brand colour to get matching palettes, shades 50–950 and CSS / Tailwind code to copy. Aspect ratio calculatorFind the ratio of a size (1920×1080 = 16:9) or enter a new width to get the height that keeps the proportions. Chmod calculatorTick read, write and execute for owner, group and others to get the chmod number and rwx — or type a number to decode it.

About Developer tools

The small tools developers reach for every day, in one place and usable on desktop or phone. Everything runs in your browser, so your data, code, tokens and files never reach our server — free and unlimited.

Each page remembers what you last typed on your device (localStorage), so you can pick up where you left off.

FAQ

Is what I paste stored?

It never reaches our server; your browser only remembers your last input on your device.

Is it free?

Yes, unlimited and with no sign-up.

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