Free online developer tools

Converts an IP address between dotted, decimal, hex and octal forms.

Computes CRC checksums using many named CRC variants.

Disassembles x86 machine code from hex into assembly.

Finds IPv4 and IPv6 addresses in text.

Decompresses gzip data.

Compresses data using gzip.

Runs jq queries on JSON input.

Strips whitespace from JSON.

Breaks an IPv6 address into its parts and reports its type.

Decodes octal, symbolic or ls-style Unix permissions.

Generates random bytes or numbers from the browser's crypto source.

Renders Markdown as formatted HTML.

Highlights source code syntax in the output.

Packs the string literals of a JavaScript module into an XOR-encoded table without eval, for Cloudflare Workers.

Vector search over documents using a Postgres running in WebAssembly (PGlite) inside the browser.

Crunches 50,000 log lines either on the main thread or in a Web Worker, so you can feel the difference in UI blocking.

Renders exported Claude widgets and artifacts offline with the missing theme styles restored, and stores them in the browser.

Side-by-side comparison and merging of text, code, Word, PowerPoint and PDF files, running offline, with extra text clean-up commands.

Runs Python in the browser through Pyodide WebAssembly, with a code editor, .py load and save, and micropip packages.

A click-to-edit visual editor for HTML pages made by AI tools, with text, color and font changes and clean HTML export.

Escapes quotes and special characters so JSON can sit safely inside a string.

Compares two JSON documents and shows how they differ.

Strips whitespace from JSON to shrink it.

Picks random network port numbers for local development.