JSON Validator – Free Online Tool
Validate JSON syntax and display detailed error messages with line numbers.
object
Type
3
Top-level keys
2
Max depth
51 B
Size
{
"name": "test",
"items": [
1,
2,
3
],
"valid": true
}Example
Input
{"name": "test", "items": [1, 2, 3]}Output
Valid JSON ✓. Type: object, 2 keys, depth 2
The validator confirms the JSON is syntactically correct and shows structural stats.
How to Use JSON Validator
- 1
Enter JSON
Paste your JSON into the input area or drag-and-drop a .json file.
- 2
View Results
The validator runs automatically and shows valid/invalid status with error details.
- 3
Fix Errors
Error messages include line numbers so you can locate and fix issues quickly.
What is JSON Validator?
The JSON Validator instantly checks whether your input is valid JSON and provides line-level error reporting when issues are found. It shows structural statistics including type, key count, nesting depth, and byte size. All validation runs in your browser. No data is sent to any server.
Common Use Cases
- ✦Checking API response payloads before processing
- ✦Validating configuration files before deployment
- ✦Debugging malformed JSON from third-party services
Frequently Asked Questions
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