JSON Validator Tool
Format, validate, and minify JSON with syntax highlighting. Free, fast, and runs 100% in your browser.
A single missing comma or extra bracket can break an entire API integration. This JSON validator checks your data against the JSON specification and highlights the exact location of any syntax errors. Perfect for debugging REST API responses, validating configuration files before deployment, or checking database exports. All processing happens locally in your browser.
Feature Overview
| Feature | Details |
|---|---|
| Syntax checking | ✓ |
| Error location | Line & character |
| Real-time validation | ✓ |
| Large file support | Up to 5MB+ |
| Privacy | 100% client-side |
Frequently Asked Questions
What errors does it catch?
Missing commas, unmatched brackets, trailing commas, single quotes instead of double quotes, and all other JSON specification violations.
Can I validate JSON from an API response?
Yes. Copy the response body from your browser's DevTools or Postman and paste it directly into the validator.
Does it fix errors automatically?
The tool identifies errors but does not auto-fix them, as automatic correction could change your data's intent. It shows you the exact location so you can fix issues yourself.