Free developer tools

Look up any HTTP status code and what it means.

See and decode any browser user-agent string.

Generate fake test data as JSON or CSV.

Full ASCII table — decimal, hex, binary, and characters.

Build a .gitignore for your languages and tools.

Convert CSV to JSON in your browser.

Break a URL into its parts and query params.

Turn plain English into a regular expression.

Write SQL queries from plain English.

Understand what any code does, in plain English.

Generate clear commit messages from a diff.

Turn a schedule in plain English into cron.

Format, validate, and minify JSON — instantly, in your browser.

Beautify and format SQL queries for any dialect.

Beautify, indent, and validate XML.

Format JavaScript, CSS, HTML, and JSON.

Write Markdown with a live preview — copy the HTML instantly.

Generate TypeScript types from JSON.

Generate a JSON Schema from an example JSON object.

Convert a cURL command to JavaScript fetch or Python requests.

Convert between px, rem, and em for CSS.

Decode and inspect JSON Web Token header and payload.

Test regular expressions against sample text with live matches.

Translate a cron expression into plain English.

Check WCAG contrast between two colors.

Convert file permissions between octal and symbolic.

Calculate subnet range, mask, and host counts from CIDR.

See your public IP address and browser details instantly.

Check a card number's Luhn checksum and detect its brand.

Test how strong a password is, privately.

Generate and verify bcrypt password hashes — Laravel & PHP compatible.

Minify and clean up SVG code to shrink the file.

Minify HTML — strip comments and whitespace.

Minify CSS to shrink stylesheet size.

Minify JavaScript with Terser.