UUID ジェネレーター

Validate, pretty-print or minify JSON with error line:col reporting

Convert Unix timestamps to dates, auto-detect seconds/milliseconds

Convert text to/from Base64, handles Unicode correctly, URL-safe mode

URL encode/decode supporting both component and full URI modes

Online regex tester with group highlighting and match details

Convert between Chinese and Unicode escape sequences

Decode JWT tokens to view header, payload, signature, and expiry

Convert between text and hex UTF-8 bytes with 0x/space format support