JSON Repair & Fixer
Repair malformed JSON, unquoted keys, Python dicts, and trailing commas
About JSON Repair & Fixer
How JSON Repair & Fixer Works
Scans and repairs relaxed JSON and Python dictionary syntax into strict RFC 8259 compliant JSON. It strips C-style comments, converts single quotes to double quotes, quotes unquoted object keys, normalizes Python booleans and None to true/false/null, removes trailing commas, and auto-closes unclosed brackets in proper LIFO nesting order without uploading your payloads.
JSON Repair & Relaxed JSON Fixer automatically scans, repairs, and reformats broken JSON payloads, Python dictionaries, and JSONC (JSON with comments) into strict RFC 8259 compliant JSON. It fixes single quotes, unquoted keys, Python literals (True, False, None), trailing commas, comments, and unclosed brackets.
Frequently asked questions
Can it convert Python dictionaries into valid JSON?+
Yes! Python dictionary outputs often contain single quotes, None, True, and False. This tool automatically converts them to double quotes, null, true, and false.
Why does standard JSON.parse reject my JSON?+
The official JSON specification (RFC 8259) prohibits comments (// or /* */), single-quoted strings, trailing commas after the last array/object element, and unquoted object keys. JSON Repair cleans all of these syntax violations.
Does it repair unclosed brackets and braces?+
Yes. If an LLM response or API stream was truncated mid-payload, JSON Repair detects missing closing brackets and braces and auto-closes them in proper LIFO nesting order.
Is my confidential JSON data uploaded to an external server?+
Never. All lexical analysis, token replacements, and formatting occur 100% client-side in your local browser sandbox.
Limitations
Severely corrupted strings with missing internal quotes or arbitrary syntax garbling may require manual review, but standard LLM and Python errors are repaired instantly.