Developer tools that run inside your browser
Paste a JSON response, a token, a CSV export — and read it here. Nothing is uploaded, because there is no server to upload it to.
Data formats
- JSON ViewerValidate, format, and explore JSON as a tree or a table. Large API responses stay foldable.
- CSV Viewer & ConverterOpen delimited data as a table, guess the delimiter, and convert it to JSON.
- CSV to JSON ConverterTurn a spreadsheet export into a JSON array, with numbers and booleans typed correctly.
- JSON to CSV ConverterTurn a JSON array into a spreadsheet, flattening nested objects and keeping every field.
- CSV to Markdown TablePaste a spreadsheet range and get a Markdown table, with the pipes escaped.
- CSV to SQL INSERTTurn rows into INSERT statements, with quotes escaped and empty cells as NULL.
- Excel to JSON ConverterOpen an .xlsx or .xls file and read it as JSON, a table, or Markdown — without uploading it.
- YAML ↔ JSON ConverterConvert YAML to JSON and back, with the parser's own error position when it will not parse.
- JSON DiffCompare two JSON documents by value, ignoring key order and formatting.
Encoding & crypto
- Base64 Encoder / DecoderEncode text to Base64 or decode it back. Handles UTF-8, emoji, and URL-safe variants.
- JWT DecoderSplit a JSON Web Token into header, claims, and signature — with expiry read as a real time.
- Hash GeneratorMD5, SHA-1, SHA-256, SHA-384 and SHA-512 of any text, computed as you type.
Web & network
Text
Time & identifiers
- Unix Timestamp ConverterTurn an epoch number into a real date — and tell seconds from milliseconds.
- Cron Expression ReaderRead a cron expression back in plain words, and see the next five times it fires.
- Quartz Cron Expression ReaderRead a Quartz expression — six or seven fields, with ? L W and # — back in plain words.
- Spring Cron Expression ReaderRead a Spring @Scheduled expression back in words — six fields, seconds first.
- UUID GeneratorGenerate v4 or time-ordered v7 UUIDs in bulk, and read the version out of an existing one.