🔍 AI JSON Error Explainer

JSON.parse() throws on the first syntax error and stops. This tool uses a custom multi-pass parser that scans the entire input to detect multiple issues — trailing commas, single quotes, unquoted keys, comments, mismatched brackets — all in one analysis. See also our JSON Formatter for validation + formatting.

Common causes: (1) trailing commas after the last item: {"a":1,}, (2) single quotes: {'a':1}, (3) unquoted keys: {a:1}, (4) comments: // comment, (5) JS-only values: undefined, NaN, Infinity. Paste your JSON above for the exact diagnosis.

JSON (RFC 8259) forbids comments and trailing commas. JSONC (JSON with Comments) allows // and /* */ comments plus trailing commas — used by VS Code's settings.json and TypeScript tsconfig.json. If you need comments, use .jsonc extension with a JSONC parser.

JavaScript: try { JSON.parse(str) } catch(e) { console.error(e) }
Python: import json; json.loads(s)
CLI: cat file.json | python -m json.tool or jq '.' file.json
These catch one error at a time — use this tool for multi-error detection.

No data is ever sent anywhere. Everything runs 100% in your browser via client-side JavaScript. No cookies, no analytics on your JSON content, no network requests. Verify yourself: open DevTools → Network tab → paste JSON → check zero outbound requests.

Yes! Click the 🔗 Share button after pasting your JSON. It encodes your input into a URL parameter using Base64. When your teammate opens the link, the JSON is auto-loaded and analyzed instantly — no copy-pasting needed.