JSON repair workflow
Repair malformed JSON without hiding the changes
A reliable repair process should explain what changed instead of silently rewriting the input.
Review before accepting repaired data
Use the repaired result as a draft, then confirm that values and structure still match the source.
Paste the malformed JSON
Keep a separate copy of the original input.
Run the repair engine
Apply conservative fixes for common JSON syntax problems.
Review the change report
Check every repair type before trusting the output.
Validate the final result
Open the repaired output in the formatter or schema validator.
The malformed patterns the repairer fixes
- Trailing commas after the last item
- Single-quoted strings and keys
- Unquoted property names
- Comments left over from JavaScript or YAML config
- JavaScript constants such as undefined or NaN
Why the change list matters
Repair is a judgment call: the tool changes the minimum syntax needed to make the document parse, and it lists every change with its location.
Review the list before accepting the output, especially for config files where a wrong value is worse than no value.
Frequent repair cases
- Trailing commas
- Single-quoted property names
- JavaScript comments
- Missing closing braces or brackets
Repair safely
- Do not assume repaired data is semantically correct
- Compare identifiers and numeric values
- Validate against a schema when available
- Avoid repairing secrets in a shared device
Frequently asked questions
Does the repairer ever change my values?
No. Only syntax is adjusted. Every change is listed so you can verify that values are untouched.
What does "conservative repair" mean?
The tool applies only unambiguous fixes and skips ambiguous spots, which it flags for manual review instead of guessing.
Can I repair JSON with comments?
Yes. Comments are removed or converted so the document parses as strict JSON.
Is the malformed document uploaded?
No. Repair runs locally in your browser.
Repair locally when possible
The repair workflow processes input in the browser and does not include pasted content in analytics.
Open JSON Repair