Free Developer Tools Online

All Developer tools

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What’s included in this category

• {}
  JSON Formatter & Validator — Beautify, validate and minify JSON instantly in your browser.
• ↔
  JSON ↔ CSV Converter — Convert JSON arrays to CSV and CSV back to JSON.
• B64
  Base64 Encoder & Decoder — Encode and decode Base64 strings, including UTF-8 and binary.
• %
  URL Encoder & Decoder — Percent-encode and decode URL components safely.
• &;
  HTML Entity Encoder & Decoder — Escape and unescape HTML entities like &, <, >.
• 🔐
  JWT Decoder — Decode JWT header and payload, view claims and expiry at a glance.
• #
  Hash Generator (MD5, SHA-1, SHA-256, SHA-512) — Compute cryptographic hashes from any text.
• 🆔
  UUID Generator — Generate v4 UUIDs in bulk, with copy-all support.
• /.*/
  Regex Tester — Test JavaScript regular expressions against a string with live highlighting.
• —
  HTML / CSS / JS Minifier — Strip whitespace and comments from HTML, CSS or JavaScript.
• 📜
  YAML Formatter & Validator — Beautify and validate YAML with selectable indent and helpful error messages.
• 🔄
  YAML to JSON Converter — Convert YAML to JSON and JSON to YAML in one click — fully in the browser.
• </>
  XML Formatter & Validator — Pretty-print and validate XML in the browser with selectable indent.
• 🔁
  XML to JSON Converter — Two-way XML ↔ JSON conversion using your browser's native XML parser.
• 🗄️
  SQL Formatter — Beautify SQL for MySQL, PostgreSQL, SQLite, T-SQL and BigQuery.
• 📰
  HTML Formatter & Beautifier — Pretty-print HTML with proper indentation and self-closed void elements.
• 🎨
  CSS Formatter & Beautifier — Pretty-print CSS with consistent indentation, including media queries.
• 𝙅𝙎
  JavaScript Beautifier — Quickly re-indent and prettify JavaScript and TypeScript.
• 📊
  CSV Formatter & Validator — Auto-detect delimiter, validate quoting, and align CSV columns.
• 🗂️
  TSV to CSV Converter — Convert tab-separated values to CSV and back, preserving quoted fields.
• ▦
  Markdown Table Generator — Build GitHub-flavoured Markdown tables visually with per-column alignment.
• ⏱️
  Cron Expression Parser — Parse a cron expression and preview the next 10 fire times.
• 🛠️
  Crontab Schedule Builder — Build a cron expression visually using dropdowns for each field.
• 🔢
  Number Base Converter — Convert numbers between binary, octal, decimal, hex and base32.
• 🔡
  Text to Binary, Hex, Octal Converter — Encode text as binary, hex or octal bytes — and decode back.
• 🔠
  ASCII Table — Searchable ASCII table with decimal, hex, octal and binary codes.
• 𝓤
  Unicode Character Lookup — Inspect any character: codepoint, HTML entities, JS escape, UTF-8 bytes.
• 📎
  MIME Type Lookup — Look up the MIME type for a file extension — or the extensions for a MIME.
• 🌐
  HTTP Status Code Reference — All standard HTTP status codes (1xx-5xx) with name and description.
• 🕵️
  User Agent Parser — Parse a UA string into browser, OS, engine and device type.
• 🔗
  URL Parser & Inspector — Break a URL into scheme, host, port, path, query and hash.
• ❓
  Query String Builder — Build a URL query string from key/value rows — or parse one into rows.
• 🧮
  IP Subnet Calculator — Compute network, broadcast, mask and host range from a CIDR.
• 🌍
  IPv4 to IPv6 Converter — Convert IPv4 addresses to IPv6-mapped or 6to4 — and extract IPv4 from IPv6.
• 🪪
  MAC Address Vendor Lookup — Find the vendor for a MAC address from its OUI prefix.
• 🎲
  MAC Address Generator — Generate random MAC addresses with optional vendor prefix.
• 🔐
  bcrypt Hash & Verify — Generate bcrypt hashes or verify a password against a hash, fully in-browser.
• 🛡️
  .htpasswd Generator — Build Apache .htpasswd lines with bcrypt or SHA-1, locally in your browser.
• 🪪
  JWT Builder & Signer — Build and HS256/HS384/HS512-sign a JWT entirely in your browser.
• 🔑
  RSA Keypair Generator — Generate a 2048/3072/4096-bit RSA keypair as PEM, fully in-browser.
• 🧪
  Mock Data Generator — Generate fake JSON data from a schema of fields and types.
• 🖼️
  Placeholder Image URL Builder — Build placeholder image URLs for placehold.co, picsum and dummyimage.
• 📚
  Regex Cheatsheet & Tester — Reference table of regex syntax with an inline live tester.
• 🪢
  String Escaper & Unescaper — Escape strings for JS, JSON, HTML, SQL, shell or regex — and reverse.