Developer Tools
Small, private, in-browser helpers for the formatting and encoding chores that interrupt your day.
JSON Formatter
Paste raw JSON and get it neatly indented, minified, or validated — entirely in your browser.
Open toolBase64 Encoder / Decoder
Encode any text to Base64 or decode it back, instantly and locally — with full Unicode and emoji support.
Open toolUUID Generator
Create one or many version-4 UUIDs for IDs, keys, and test data — generated securely on your device.
Open toolEpoch / Timestamp Converter
Convert a Unix timestamp to a date (and back), in seconds or milliseconds, with ISO, UTC, and local formats.
Open toolPassword Generator
Generate secure random passwords with your choice of length and character sets, using the Web Crypto API.
Open toolRandom String Generator
Generate any number of random strings at a chosen length from the character sets you pick — lowercase, uppercase, numbers, and symbols — and copy them one by one or all at once.
Open toolHash Generator
Compute cryptographic hash digests of any text with the SHA family, locally via the Web Crypto API.
Open toolJWT Decoder
Decode a JSON Web Token to read its header and payload claims — locally, with no signature verification.
Open toolURL Encoder / Decoder
Encode text so it's safe to put in a URL, or decode percent-encoded text back to readable form.
Open toolColor Converter
Convert a color between HEX, RGB, and HSL, with a live swatch preview and one-click copy — paste any of the three formats.
Open toolText Diff
Compare two blocks of text line by line and see exactly what was added, removed, or left unchanged.
Open toolJSON Diff
Compare two JSON objects and get a clear list of the fields that were added, removed, or changed — with full paths.
Open toolJSON ↔ CSV ↔ YAML
Convert data between JSON, CSV, and YAML in any direction — paste one, pick a target, and copy the result.
Open toolRegex Tester
Test a regular expression against sample text with live match highlighting, a plain-English breakdown of your pattern, and a cheat sheet to learn from.
Open toolQR Code Generator
Generate a QR code for any text or URL and download it as SVG or PNG — encoded entirely in your browser with no third-party libraries.
Learn moreMarkdown Preview
Convert Markdown to formatted output as you type — headings, lists, tables, links, and fenced code — with a one-click view of the HTML it generates. Paste text or open a .md file.
Open toolWeb Playground
Write HTML, CSS, and JavaScript in three panes and see the result render instantly in a sandboxed preview. A fast scratchpad for trying an idea, a snippet, or a layout.
Open tool