JSON Formatter & Validator
Validate and pretty-print JSON. Useful for inspecting API responses, debugging config files, or reformatting minified JSON.
Inputs
Formatted output
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Formatted size
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Minified size
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Key count
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Max nesting depth
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About JSON Formatter & Validator
Common JSON errors
Trailing commas, single quotes instead of double, unquoted keys, comments. JSON is strict. JSON5 supports these but is not standard JSON.
When to minify
For network transmission — saves bandwidth. For storage/version control — keep pretty-printed for readability. Many APIs accept both.
Security note
This tool runs entirely in your browser; nothing is sent to a server. Still — never paste secrets or PII into any web tool without verifying.