JSON lint

JSON Linter

Valid JSON can still be wrong: a key that appears twice (JSON.parse keeps only the last), one key in snake_case among camelCase ones, or a list of numbers with a string in it. Paste JSON to see each problem with its line.

How do I use the JSON lint?

1. Paste JSON or open a file.
2. Pick the key style to check, or let it use the style most keys follow.
3. Click a problem's path to find it in the input.

What does the JSON lint do?

• Duplicate keys, with the line of the first one
• camelCase, snake_case, kebab-case, PascalCase or CONSTANT_CASE, or the style most keys use
• Keys like _id and $schema judged without their prefix
• Lists that mix types, with nulls allowed or not
• A suggested name for each key in the wrong style
• Copy gives every problem as JSON

Frequently asked questions

Why doesn't Beautify report duplicate keys?

Because they're valid JSON: the standard says names should be unique, but parsers accept them and keep the last value. The linter reads the text itself to find them.

Is my data uploaded?

No. Bracely runs entirely in your browser, so nothing you paste or open leaves your device.

More JSON tools

Bracely has more than 65 JSON tools in one page. Related ones:

• JSON Formatter
• JSON Validator
• JSON Minifier
• JSON Repair
• Sort JSON
• JSON to chart
• GeoJSON viewer
• QR code generator
• Webhook signature
• JSON Viewer
• JSON Diff
• JSON to YAML
• JSON to CSV
• jq Playground

Runs entirely in your browser. Nothing you paste is uploaded. Made by Saurabh Pagrut. About · Privacy policy
Last updated 22 October 2026 · Version 4.9 · Changelog
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