Free Developer Tools
Format JSON, test regex, decode JWTs, generate UUIDs, hash strings, encode Base64, compare text diffs — all in your browser with no signup, no rate limits.
14 free tools — no signup required
JSON Formatter
Format, validate, and minify JSON instantly
CSV to JSON Converter
Convert CSV files to clean JSON instantly — free, private, no upload
JSON to CSV Converter
Convert JSON arrays to CSV — free, private, instant download
Base64 Encoder / Decoder
Encode and decode Base64 text and files instantly
UUID Generator
Generate UUIDs v1, v4 & v7 instantly in your browser
Regex Tester
Test and debug regular expressions with live match highlighting
JWT Decoder
Decode and inspect JWT tokens — header, payload, claims, expiry
Hash Generator
Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from text or files
Markdown Editor
Write Markdown with a live split-pane preview — download .md or copy HTML
Password Generator
Generate secure, random passwords instantly
Text Diff Checker
Compare two texts and highlight the differences instantly
Lorem Ipsum Generator
Generate placeholder text for designs and prototypes instantly
Color Contrast Checker
Check WCAG color contrast ratios for accessible web design
CSS Gradient Generator
Build beautiful CSS gradients visually and copy the code instantly
Free Developer Tools — All Tools Listed
Every tool below is 100% free, requires no account, and runs entirely in your browser — your data never leaves your device.
🔧 Free JSON Formatter
Free JSON formatter and validator. Paste messy JSON to instantly format, validate, and highlight errors. Supports minify, indent options, and copy. No signup required.
📋 Free CSV to JSON Converter
Free CSV to JSON converter. Paste or upload any CSV file and get clean, formatted JSON in seconds. Auto-detects delimiter, handles headers, supports large files. 100% in-browser, no signup.
🔄 Free JSON to CSV Converter
Free JSON to CSV converter. Paste or upload a JSON array of objects and download a clean CSV in seconds. Handles nested objects with dot-notation flattening. 100% in-browser, no signup.
🔢 Free Base64 Encoder / Decoder
Free Base64 encoder and decoder. Encode text or files to Base64 and decode Base64 strings back to text. Supports file to data URI encoding. No signup required.
🆔 Free UUID Generator
Free UUID generator. Generate version 1, 4, and 7 UUIDs in bulk — individually or as a JSON / newline list. Runs 100% in your browser. No signup, no server.
🔣 Free Regex Tester
Free online regex tester with live match highlighting, capture groups, named groups, and full flag support. Supports JavaScript (ECMAScript) regex syntax. No signup required.
🔓 Free JWT Decoder
Free JWT decoder. Paste any JSON Web Token to instantly see the decoded header, payload claims, expiry status, and signature. 100% browser-side — your token never leaves your device.
# Free Hash Generator
Free hash generator. Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 cryptographic hashes from text or files. Verify file integrity and checksums instantly in your browser. No upload, no signup.
📋 Free Markdown Editor
Free online Markdown editor with live split-pane preview. Write Markdown on the left, see the rendered HTML on the right. Download your .md file or copy the rendered HTML. No signup.
🔐 Free Password Generator
Generate strong, cryptographically secure passwords instantly. Choose length up to 64 chars, character types — up to 10 at once. Never sent anywhere. Free, no signup.
🔍 Free Text Diff Checker
Free text diff checker. Paste two blocks of text to instantly see what was added, removed, or changed line by line. Great for comparing documents, code, or any text. No signup required.
📝 Free Lorem Ipsum Generator
Free lorem ipsum generator for designers and developers. Generate paragraphs, sentences, or words in plain text, HTML, or Markdown. No signup required.
🎨 Free Color Contrast Checker
Free WCAG color contrast checker. Enter foreground and background colors to instantly see the contrast ratio and whether it passes WCAG 2.1 AA and AAA standards for normal and large text. No signup.
🌈 Free CSS Gradient Generator
Free CSS gradient generator. Build linear, radial, and conic gradients visually — add color stops, set positions and angles — and copy the ready-to-use CSS. No signup.