Developer / BROWSER-LOCAL

JSON Formatter / Validator

Validate, format and compact JSON without uploading your input.

Processed on your device

Output

InputMaximum 200,000 characters. Input is not stored.

Result

Ready. Use Ctrl/⌘ + Enter to run.

Completed and failed run counts are stored only on this device.

How to use this tool

Paste JSON, choose formatted or compact output, then select Run. Syntax errors clear previous results.

200,000 characters maximum. JavaScript number precision applies; use strings for large identifiers.

Does my input leave my browser?

No. A local browser worker processes it. Input is not stored.

Does this validate a schema?

This checks JSON syntax only, not an application-specific schema.

Developer

Convert JSON and YAML 1.2 locally, with duplicate-key and alias limits.

Developer

Convert CSV tables and JSON arrays of flat objects. CSV output escapes spreadsheet formula prefixes.

Developer

Indent XML locally without enabling external entities or DTD declarations.