JSON Repair & Fix

What JSON errors it fixes

Most 'Unexpected token' and 'Invalid JSON' errors come from a small, predictable set of mistakes. The repair tool detects and corrects them automatically so you don't have to hunt through thousands of characters by hand.

• Markdown ```json code fences from LLM output
• Trailing commas before a closing } or ]
• Single-quoted 'strings' converted to double quotes
• Unquoted object keys, e.g. {name: 1} to {"name": 1}
• Smart / curly quotes pasted from docs and chat
• Leading prose or explanations wrapped around the JSON

How JSON repair works

JsonDrift repairs syntax, not meaning. Each pass applies conservative, rule-based transforms that only touch structural characters — quotes, commas, braces, and fences — never your actual values. The cleaned text is then parsed with a strict JSON parser to guarantee the output is valid, and pretty-printed with consistent indentation.

Because every step is deterministic and runs locally, the same input always produces the same output, and nothing is uploaded to a server — safe for production payloads and secrets.

Fixing JSON from ChatGPT and LLMs

Large language models frequently wrap JSON in ```json fences, add a sentence of explanation, use single quotes, or leave trailing commas — all of which break JSON.parse(). Paste the raw model response here to strip the noise and recover clean JSON before it reaches your application or API.

For heavier LLM-specific problems like output truncated by token limits, try the AI JSON Repair tool, which adds prose isolation and truncation recovery on top of these core fixes.

When repair is not enough

Severely corrupted text or JSON truncated mid-value may still fail to parse — there simply isn't enough information to reconstruct it safely. When that happens, run the input through the JSON Validator to see the exact line and column of the remaining error, then fix it by hand in the JSON Editor.

Repair, validate, and format

Use JSON Repair to recover broken JSON, the JSON Validator to confirm it is syntactically correct and locate errors, and the JSON Formatter to beautify readable output. Together they cover the full paste, fix, verify, and prettify workflow — all client-side.