01 Runs in your browser Developer Tools Free, client-side utilities. No data leaves your browser. Inspect and decode Base64 Codec Encode and decode Base64 strings with Unicode support. JWT Decoder Decode and inspect JSON Web Tokens with claim explanations. Transform JSON Formatter Pretty-print, minify, and validate JSON with instant feedback. PDF → Markdown Convert PDF documents to Markdown. Best with single-column text. Color Converter Convert between HEX, RGB, HSL, OKLCH. Contrast checker and palette generator. Timestamp Converter Convert between Unix, ISO 8601, and human-readable dates with timezone support. Test and compare Regex Tester Test regular expressions with live match highlighting. Diff Viewer Compare two texts with side-by-side or unified diff highlighting. Create UUID Generator Generate single or bulk v4 UUIDs with one click. Cron Builder Build cron expressions visually with human-readable explanations. Open local data Parquet Viewer Browse Parquet files in your browser. View schema, filter, sort, and export. SQLite Browser Browse SQLite databases in your browser. Run queries, inspect schema, export data.