Gitignore Generator
Build a .gitignore from templates for your stack, editor and OS.
Developer Tools
Format, encode and hash without leaving the tab.
167 free tools
No sign-up
Nothing uploaded
Test Credit Card Generator
Generate Luhn-valid test card numbers that no processor will ever charge.
JavaScript Formatter
Re-indent JavaScript, with strings and regular expressions left alone.
HTML Formatter
Re-indent HTML without breaking whitespace-sensitive elements.
Keyframes Animation Generator
Build CSS keyframe animations and watch them run as you edit.
CRC32 Calculator
Compute a CRC-32 checksum in hex, decimal and signed form.
TOML Formatter
Tidy a TOML file: consistent quoting, ordered tables, keys before headers.
URL Encoder & Decoder
Percent-encode URLs and query strings, or decode them back to plain text.
Text to Code Comment
Turn a block of text into a comment in any language, wrapped and aligned.
Code Diff Viewer
Compare two files side by side and export a unified diff.
Regex Tester
Test a regular expression live, with every match and capture group shown.
Cubic Bezier Generator
Draw an easing curve and see it against the standard ones.
HTTP Header Parser
Paste raw HTTP headers and get them parsed, explained and checked.
MongoDB ObjectId Generator
Generate and decode MongoDB ObjectIds, including their embedded timestamp.
Emoji Unicode Lookup
Break an emoji into its code points, modifiers and joiners.
HTML to Markdown
Convert HTML back into clean Markdown, keeping lists, tables and code.
Password Generator
Strong random passwords and passphrases, generated locally.
Chmod Calculator
Convert file permissions between octal, symbolic and checkboxes.
License Generator
Pick an open source licence and get a LICENSE file with your details.
Luhn Validator
Check any number against the Luhn checksum and see the working.
Text Shadow Generator
Build text shadows, outlines and glows with a live preview.
Quoted-Printable Encoder
Encode and decode quoted-printable, the MIME encoding in every email header.
Base64 to Hex
Convert Base64 back to hexadecimal, with your choice of separator.
GitHub Actions Generator
Generate a CI workflow with caching, a version matrix and the right permissions.
Fake Address Generator
Generate plausible addresses in the format each country actually uses.
Cron Expression Generator
Build a cron schedule from controls and see the next times it runs.
JavaScript Keycode Tester
Press any key and see event.key, event.code and the modifier state.
CSS Filter Generator
Stack CSS filters on a real image and copy the declaration.
CORS Header Generator
Generate correct CORS headers, and understand why the request was blocked.
CSP Generator
Build a Content-Security-Policy header directive by directive.
Nano ID Generator
Generate Nano IDs — shorter than a UUID, and URL-safe by design.
Random String Generator
Generate cryptographically random strings over any alphabet you choose.
File Checksum Calculator
Verify a download by computing its SHA-256 without uploading it anywhere.
String Byte Counter
Measure text in UTF-8 bytes, code points, UTF-16 units and graphemes.
Base58 Encoder & Decoder
Encode and decode Base58 in the Bitcoin, Ripple or Flickr alphabets.
JSON to Go Struct
Generate Go structs with json tags from a sample payload.
IP Subnet Calculator
Network, broadcast and host range from any CIDR block.
Email Format Validator
Check an email address against the rules that actually matter, and see why.
CSS Triangle Generator
Generate the border trick that makes triangles and tooltip arrows.
CSS Grid Generator
Draw a grid layout and get the CSS, including named template areas.
No tools in this category yet.