JSON Validator & Linter
JSON Validator & Linter checks your JSON for errors with detailed messages showing exactly where the problem is. Also formats and minifies. All in your browser.
Last updated: July 2026
A JSON validator checks your JSON for syntax errors and shows detailed messages with line and column numbers so you can fix them fast. It also formats and minifies JSON. Everything runs in your browser; nothing is uploaded.
How to use JSON Validator & Linter
- Paste your JSON.
- The validator checks automatically and highlights any errors.
- Format or minify with one click, then copy the result.
Frequently asked questions
What errors does it detect?
All standard JSON syntax errors: trailing commas, missing quotes, invalid values, unmatched brackets, duplicate keys and more.
Does it show line numbers?
Yes — every error message includes the exact line and column number where the problem was found.
Is my JSON uploaded?
No — validation is done locally in your browser.
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