JSON Formatter & Validator
Instantly format and validate JSON. Broken or malformed? AI repairs it automatically with a changelog of fixes.
Formatted JSON will appear here
Broken JSON is repaired automatically by AI
Frequently Asked Questions
What types of broken JSON can it repair?▼
Common issues: single quotes instead of double quotes, trailing commas, unquoted keys, missing commas, comments (// or /* */), and minor structural errors. For heavily corrupted or non-JSON data, the repair may not succeed.
Is JSON repair done with AI or rule-based?▼
Valid JSON is formatted client-side instantly — no AI call needed. Only when JSON.parse fails does the tool call DeepSeek to attempt a repair. The repair report shows exactly what was changed.
What does 'Sort keys' do?▼
Alphabetically sorts all object keys at every nesting level. Useful for diffing JSON objects and making API responses easier to read consistently.
Is there a size limit?▼
Up to 500 KB for valid JSON (formatted locally). AI repair is limited to 8 KB of broken input due to API token limits. For large files, fix them in chunks.