Free & 100% in your browser — your data never leaves this device
Create custom QR codes for websites, Wi-Fi credentials, vCards, and emails — or decode existing QR code images instantly.
QR codes are everywhere — learn to create and audit them safely with the Digital Security skill.
Interactive Git graph & CLI sandbox
Master Git branching, rebases, merges, cherry-picks, detached HEAD, and stashes with a live reactive DAG graph and interactive terminal.
Typing test for developers
Practice everyday typing, code symbols, terminal commands, and long-form developer text. Tracks WPM, accuracy, streak, and consistency score.
Live markdown preview
Split-pane markdown editor with real-time preview. Perfect for writing README files, documentation, and blog posts with export to HTML.
Visual gradient generator
Build linear, radial, and conic CSS gradients visually. Add stops, adjust angles, and copy ready-to-use CSS or Tailwind classes.
Mermaid diagram editor & previewer
Interactive Mermaid diagram editor with live SVG rendering, theme selection, presets, zoom/pan canvas, and export to SVG, PNG, and .mmd.
Format & validate JSON
Paste raw JSON to instantly format, validate, and minify it. Essential for debugging API responses and reading nested data structures.