Developer Tools
JSON, XML and SQL formatters, hash generators, JWT decoders, regex testers and everyday utilities for developers.
31 tools · all free, all run in your browser
Chmod Calculator
Tick read, write and execute for owner, group and other to get the octal chmod value, the symbolic string and the command to run.
Open toolCron Expression Generator
Build a cron schedule from plain options and read back exactly what it means in English.
Open toolCSS Minifier
Shrink CSS by removing comments, whitespace and the last semicolon in each rule.
Open toolCSV to JSON Converter
Turn CSV or TSV data into a clean JSON array, with automatic number and boolean detection.
Open toolGitignore Generator
Pick the languages, frameworks, editors and operating systems in your project and get a combined .gitignore file.
Open toolHash Generator
Generate MD5, SHA-1 and SHA-256 hashes of any text instantly in your browser.
Open toolHTML Entity Encoder & Decoder
Escape characters that would break HTML into entities, or decode entities back into readable text.
Open toolHTML Formatter & Minifier
Indent messy HTML for readability or strip whitespace and comments to minify it.
Open toolHTTP Status Code Lookup
Look up any HTTP status code by number or search by name to see what it means, whether it is cacheable and what usually causes it.
Open toolImage to Base64 Converter
Convert an image into a Base64 data URI you can paste directly into CSS, HTML or JSON — nothing is uploaded.
Open toolJavaScript Minifier
Strip comments and unnecessary whitespace from JavaScript to reduce file size.
Open toolJSON Formatter & Validator
Beautify, minify and validate JSON with clear error messages and a breakdown of the structure.
Open toolJSON to CSV Converter
Convert an array of JSON objects into CSV, ready to open in Excel or Google Sheets.
Open toolJSON to TypeScript
Paste a JSON payload and get TypeScript interfaces with inferred types, nested objects and array element types.
Open toolJWT Decoder
Decode a JSON Web Token to inspect its header, payload, expiry and claims — without sending it anywhere.
Open toolMarkdown Table Generator
Paste comma or tab-separated data and get a ready-to-use Markdown table.
Open toolMarkdown to HTML Converter
Convert Markdown to clean HTML with a live preview — free, and nothing you write is uploaded.
Open toolMeta Tag & Open Graph Generator
Generate a page's title, meta description, canonical, Open Graph and Twitter Card tags, with a live Google-style preview.
Open toolMIME Type Lookup
Find the MIME type for any file extension, or search by type to see which extensions use it, with notes on which need a charset.
Open toolNumber Base Converter
Convert a number between binary, octal, decimal and hexadecimal, all at once.
Open toolRegex Tester
Test a regular expression against sample text and see every match, capture group and position.
Open toolRobots.txt Generator
Build a robots.txt file with crawl rules, sitemap references and optional blocking of AI training crawlers.
Open toolRoman Numeral Converter
Convert a number to Roman numerals or a Roman numeral back to a number, automatically.
Open toolSQL Formatter
Format SQL queries with consistent keyword casing and line breaks so they are easy to review.
Open toolString Escaper
Escape or unescape a string for JSON, JavaScript, SQL, CSV, a shell command, a regular expression or an HTML attribute.
Open toolText Diff Checker
Compare two blocks of text line by line and see exactly what was added, removed or changed.
Open toolURL Parser
Break any URL into its protocol, host, port, path, query parameters and fragment, with each parameter decoded.
Open toolUser Agent Parser
Break a user agent string into browser, version, rendering engine, operating system and device type.
Open toolWhat Is My IP Address
See your public IP address, approximate location and browser details — nothing is stored.
Open toolXML Formatter
Indent and tidy XML, RSS or SVG markup so nested structures are easy to read.
Open toolYAML to JSON Converter
Convert YAML into JSON or JSON back into YAML, covering nested maps, lists, quoted strings and comments.
Open toolThese are the everyday utilities that sit between writing code and shipping it: pretty-printing an API response, checking a regular expression against real input, decoding a JWT to see why an request is being rejected, or converting a CSV export into JSON. All of them run entirely in your browser, which matters more here than anywhere else on the site — you can paste a production payload, an access token or a proprietary query without it leaving your machine or appearing in someone else's logs.
Formatters and validators
Minified JSON, a single-line SQL query or a compressed XML document are all valid but unreadable. Formatting restores the structure so you can see nesting, spot the missing bracket and read a diff properly. The JSON formatter doubles as a validator: because it parses before it prints, a syntax error surfaces immediately with the position and reason, which is usually faster than hunting for a trailing comma by eye.
Inspecting tokens and hashes
A JWT is three Base64URL segments, and its payload is encoded rather than encrypted — anyone holding the token can read the claims. Decoding one locally is the quickest way to check an expiry time or an audience mismatch. Hashing is the opposite operation: one-way, deterministic and useful for integrity checks. MD5 and SHA-1 remain useful as checksums but are broken for security purposes, and neither should ever be used to store passwords.
Testing patterns and comparing versions
A regex that works on one example often fails on the next, so testing against a realistic block of text — with every match, index and capture group visible — catches problems before they reach production. Similarly, a line-by-line diff built on the same longest-common-subsequence approach as git makes it obvious what actually changed between two versions of a config file, a log or a block of code.