Free online developer tools

Edits, formats and validates JSON text, with a tree view, in a browser tab.

Tries regular expressions against sample text and shows matches live.

Converts UTF-8 text to Base64 and Base64 strings back to text.

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.

Parses and validates .env files, finds duplicate keys and secrets, compares environments and converts to JSON or YAML.

Reads a pasted curl command and writes equivalent HTTP client code for several languages; the command is never run.

Compresses text or decompresses gzip, zlib and Brotli payloads, including Base64 blobs, in the browser.

Escapes or unescapes special characters in JSON strings in the browser.

Points at a remote MCP endpoint to browse the capabilities it exposes and try calling one with your own arguments.

Beautifies XML and flags syntax errors immediately, processing the text locally.

Checks XML for malformed tags, nesting and attribute errors and reports document statistics locally.