Help
- The editor on the left marks JSON error locations in real time. Click the "Repair JSON" button to automatically repair the JSON and display it on the right.
- Supports fixing common issues such as missing quotes, missing commas, trailing commas, single quotes, comments, truncation, and Python constants (None/True/False).
- If the input is already valid JSON, the repaired result is identical to the formatted result.
- When the repair changes anything, a before/after comparison appears below, showing the original JSON on the left and the repaired JSON on the right, so you can see exactly what was fixed.
JSON Repair
This free online JSON repair tool fixes broken JSON in one click.
All tools on this site run entirely in your browser locally. No data is uploaded to any server.
Common issues that can be repaired:
- Missing quotes: unquoted keys or string values, e.g. {name: "John"}
- Missing commas: commas omitted between object or array elements
- Trailing commas: an extra comma after the last element
- Single quotes: single quotes used instead of double quotes, e.g. {'name': 'John'}
- Special quotes: special characters such as Chinese curly quotes “”‘’
- Comments: /* ... */ or // ... comment blocks
- Truncated JSON: content cut off, leaving brackets/quotes unclosed
- Python constants: None/True/False converted to null/true/false
- Escaped strings: redundant escape characters, e.g. {\"key\": \"value\"}
- JSONP: a callback({...}) wrapper around the JSON
- Code block markers: ```json ``` fences
- Ellipsis: ... placeholders in arrays/objects
- Multi-line JSON: multiple newline-separated JSON entries merged into an array
Common uses:
- Repairing malformed JSON data returned by APIs
- Repairing JSON snippets copied from code (unquoted keys, etc.)
- Repairing JSON in truncated log files
- Repairing non-standard JSON generated by LLMs