JSON validator
Check that JSON is valid and find the exact error: line, column and a plain explanation. Comments and trailing commas fixed in one click.
Accepted: JSON, CSV, TSV, XML, YAML, YML, TXT, GEOJSON, JSONC · Max 50 MB per file
Processed on your device — nothing is uploaded.
Tip: paste text anywhere on the page (Ctrl+V).
How to validate JSON
Paste your JSON or drop the file.
The verdict appears at once; on error, “Go to error” puts the cursor on it.
Fix it right in the box, or click Repair for comments and trailing commas.
Why use this tool
- Instant verdict
- Valid or not, with the number of items, columns and nesting depth. YAML also reports duplicate keys.
- Errors explained
- A missing comma, a badly closed tag, wrong indentation: the line and column are shown, the line is highlighted and “Go to error” puts the cursor there.
- One-click repair
- Comments, trailing commas, single quotes, unquoted keys: the most common slips in hand-written JSON are fixed automatically.
- Nothing leaves your device
- The conversion runs in your browser: your data is never sent to a server, even 50 MB files.
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