JSON Validator & Lint

Validate JSON syntax, find errors with line numbers, pretty-print and view stats.

Your data stays in your browser
Tutorial

How to use

1
1

Paste your JSON

Enter or paste the JSON data you want to validate into the input area.

2
2

Click Validate

Press the validate button to check your JSON for syntax errors.

3
3

Review results

See if your JSON is valid, view formatted output with stats, or fix errors shown with line numbers.

Use Cases

Use cases

API Response Debugging

"Quickly validate and format API responses to spot malformed data."

Config File Validation

"Check JSON configuration files for syntax errors before deploying."

Data Inspection

"View key counts, nesting depth and size stats of any JSON document."

Frequently Asked Questions

?What JSON errors does this tool detect?

The tool detects all JSON syntax errors including missing commas, unquoted keys, trailing commas, unclosed brackets, and invalid values. Error messages include line and column numbers to help you find the issue quickly.

?Is my JSON data kept private?

Yes, all validation happens entirely in your browser. Your data is never sent to any server, ensuring complete privacy and security.

?What stats does the tool show?

For valid JSON, it shows the data type (Object/Array), total number of keys, maximum nesting depth, and the data size in bytes.

?Can I use this to format minified JSON?

Yes, the tool automatically pretty-prints valid JSON with proper indentation, making minified JSON easy to read.

?Does it support large JSON files?

The tool works well with moderately sized JSON data. For very large files (over 10MB), performance may vary depending on your browser.

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