Format and validate JSON without leaving your browser.
Paste JSON to pretty-print it with two-space indentation and catch a syntax error before it reaches an API or a file.
JSON input
Formatted JSON
text
Processed locally — inputs and results stay in this browser tab. Copy and download actions run only when you choose them.
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Parse a five-field cron expression and see the minute, hour, day, month, and weekday fields explained in plain language.
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Compare two blocks of text line by line and see exactly which lines were added, removed, or unchanged, locally in your browser.
What "valid" means here
This formatter checks that the input is syntactically valid JSON and re-indents it. Syntax validity is only the first contract an API request has to satisfy — a schema, required field, or type mismatch can still reject a payload that formats cleanly.
- Trailing commas and comments are not valid JSON and are rejected.
- Formatting uses two-space indentation.
- Large or deeply nested payloads still format entirely in this browser tab.
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Inspect, transform, and debug data without sending it away.