Developer
JSON Formatter / Validator
Validate, format and compact JSON without uploading your input.
Open toolCSV ↔ JSON Converter
Convert CSV tables and JSON arrays of flat objects. CSV output escapes spreadsheet formula prefixes.
Maximum 200,000 characters. Input is not stored.
Ready. Use Ctrl/⌘ + Enter to run.
Completed and failed run counts are stored only on this device.
How to use this tool
CSV requires a header row with unique non-empty names. JSON-to-CSV requires a non-empty array of flat objects.
Supported input and limits
CSV values remain strings. Nested JSON objects are rejected. Formula-like CSV cells are prefixed for safer spreadsheet opening. Maximum main input: 200,000 characters.
Frequently asked questions
Does my input leave my browser?
No. A local worker processes it; text and files are not uploaded or stored.
Are CSV numbers automatically converted?
No. Values remain strings to preserve identifiers and leading zeros.
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