JSON Formatter

Free JSON pretty printer with readable syntax error messages.

Private browser-side processing
Input JSONJSON
Paste an API response or config snippet and format it immediately.
1 lines · 59 bytes
Formatted outputJSON
No action has been run yet.
0 lines · 0 bytes

Why use this JSON Formatter

Fast formatting

Turn compact or messy JSON into readable structured output for debugging, documentation, and operations workflows.

Browser-side processing

The formatter runs fully in the browser, which keeps the experience fast and avoids sending your input to a backend service.

Readable errors

When JSON is invalid, the tool highlights the likely line area so users can fix the input quickly without deciphering raw parser output.

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