Free Online JSON Formatter That Also Fixes Broken JSON With AI

Needed a JSON formatter that could also fix broken JSON — missing commas, unquoted keys, trailing commas, comments.

Built one: jsonfix-lake.vercel.app

Three modes:

1. Format and Validate — paste JSON, get pretty-printed output
2. Minify — compress JSON to one line
3. AI Fix — paste broken JSON, AI repairs it and returns valid JSON

The AI Fix handles: single quotes, unquoted keys, trailing commas, JavaScript comments in JSON, missing brackets, and truncated data.

No signup. Free. Runs on Next.js + Claude API.

Part of a collection of 15 free developer tools.