A little kit of everyday dev tools
Fast, private, and runs entirely in your browser. Nothing you type ever leaves your device — only the IP tool asks the network about your connection.
Data & formats8
JSON formatter
Validate and beautify JSON, with clear error locations.
SQL formatter
Format and beautify SQL — multiple dialects.
XML formatter
Format and validate XML — beautify or minify.
CSV to JSON converter
Convert CSV to JSON and back — quoting handled properly.
JSON to YAML converter
Convert JSON to YAML, with every quote explained.
JSON to TypeScript
Infer TypeScript interfaces from a JSON sample.
JSONPath tester
Test RFC 9535 JSONPath queries against JSON.
Markdown table generator
Build and align Markdown tables from CSV, TSV or JSON.
Text & strings6
String length
Count characters, words and lines — Unicode aware.
Regex tester
Test regular expressions — match, replace, split.
Text diff
Compare two texts — every changed line and word.
Unicode character inspector
See exactly which characters a string is made of.
URL slug generator
Turn any title into a clean URL slug.
Case converter
Convert between camelCase, snake_case, Title Case and more.
Encoding & escaping5
Base64
Encode and decode Base64 — full UTF-8 support.
URL encoder / decoder
Percent-encode a value or a whole URL, and back.
JSON string escape / unescape
Escape text for a JSON string, or read an escaped one back.
HTML entity encoder / decoder
Escape text for HTML, or turn entities back into characters.
Data URI generator
Turn a file or text into a data: URI, and read one back.
Security & crypto5
JWT decoder / verifier
Decode and verify JSON Web Tokens — signature and claims.
Hash generator
MD5, SHA-1, SHA-256, SHA-384 and SHA-512 at once.
Certificate & PEM decoder
Read an X.509 certificate or CSR without OpenSSL.
HMAC generator & signature checker
Sign a message with a key, or verify a webhook signature.
TOTP / 2FA code debugger
Generate and debug 2FA codes, with the full derivation.
Generators4
Network & system5
Unix timestamp converter
Convert epoch time to a date, and back.
Chmod calculator
Turn file permissions between octal, symbolic and checkboxes.
CIDR / subnet calculator
Break a network down, check membership, and split it up.
Cron expression explainer
Read a cron expression, and see when it really runs.
What is my IP
Your public IPv4 and IPv6, and which one your browser used.
Images & colour4
Colour converter & contrast checker
Convert between colour formats and check WCAG contrast.
JPG to PNG converter
Turn a JPG into a PNG in your browser, and see what changed.
WebP converter
Make a WebP to save bytes, or turn one back into a PNG or JPG.
SVG to PNG converter
Turn an SVG into a PNG at whatever pixel size you need.