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Review safe JSON repairs.
Remove enclosing JSON code fences or trailing commas, with the original and exact proposal side by side. Nothing changes until you apply a reviewed correction.
Step 1: open your file
Choose malformed .json up to 2 MiB, or paste its text. Contents stay in this browser.
- Preview supported fence/trailing-comma corrections; compare original and exact proposed source.
- Apply only after review, Undo if needed, then download valid JSON.
Paste JSON
File contents stay in this browser. Download changes before refreshing or closing the tab.
```json
{"project":"Harbour survey","id":9223372036854775807,}
```After review and Apply{"project":"Harbour survey","id":9223372036854775807}Edit, format and validate
Repair only supports the explicit fence and trailing-comma corrections. Fix other syntax problems manually in Source; no missing content is invented. Syntax problems are reported without sending the document to a server.
Choose the matching format
Use JSON for one complete value, JSONL or NDJSON for one JSON value per line.
Frequently asked questions
Can I convert JSONC comments to strict JSON?
In the browser editor, open a .jsonc file or paste JSONC source, then choose Repair and JSONC to strict JSON. Safe JSON repairs remains the default task. Review the complete original and converted result before downloading a separate .json copy or explicitly applying one undoable edit. Only comments and trailing commas are removed; numeric and string tokens remain unchanged. Ordinary formatting still requires strict JSON. Duplicate keys and JSON5 syntax are refused. Conversion supports up to 2 Mi characters, 128 container levels and 100,000 tokens/values, with local cancellation and a five-second limit. Native file associations, installed versions and integration support can differ.
Can I convert JSON5 to strict JSON without rounding numbers?
Choose Repair and JSON5 to strict JSON in the browser editor. Review the complete original and proposal, then download a separate .json copy or explicitly Apply; Undo restores the original. Supported JSON5 data includes comments, trailing commas, unquoted keys, single-quoted strings, signed decimals and hexadecimal integers. Strict decimal number spellings are retained, including values beyond JavaScript number range; hexadecimal integers convert exactly. Strings and keys are quoted or escaped when required. NaN, Infinity, decoded duplicate keys, JavaScript expressions and unsupported syntax are refused. Limits are 2 Mi source/output characters, 10,000 characters per numeric token, 100,000 tokens/values and 128 container levels, with local cancellation and a five-second deadline. Ordinary formatting and the separate JSONC task retain their strict policies. This does not provide comment-preserving JSON5 structured editing or certify installed/integration versions.
Which JSON errors can this repair?
Preview removal of a complete enclosing Markdown JSON code fence and trailing commas. Corrections are offered only if the exact parser accepts the result. Missing values, keys, quotes and closing brackets are never invented; Use the separate explicit JSONC or JSON5 task for supported variant conversion; Safe JSON repairs does not admit those variants.
Will repair change my original file automatically?
No. The original source and exact proposed result remain visible until you choose Apply reviewed repair. One Undo restores the original text. Downloading a copy is separate, and invalid JSON cannot be downloaded as a corrected result.
Are large numeric values and Unicode preserved?
Supported corrections splice unchanged source text rather than converting numbers through JavaScript Number. Exact numeric tokens, string escapes, Unicode and surrounding whitespace stay intact apart from the explicitly listed corrections. Entry is limited to 2 MiB and repair review to 2 Mi characters.
Does my JSON file get uploaded?
Local editing processes selected and pasted contents in your browser. Optional Assistance sends your goal and only the context you explicitly prepare and include, such as a selected subtree or observed query field metadata, to OpenRouter and the configured model provider. Its preview shows exactly what is included. Ordinary page and asset requests also reach the hosting provider.