JSON Validator
Validate and format JSON instantly. Paste your JSON to detect syntax errors, fix formatting, and get clean, readable output. Free online JSON validator — no install needed.
Output will appear here
Press ⌘ Enter to convert
How It Works
- 1Paste your JSON into the input box
- 2The validator checks syntax in real time and highlights errors
- 3Click Convert to format and pretty-print the JSON
- 4Copy the formatted output or download it as a .json file
Examples
Input
{"id":1,"name":"Alice","email":"[email protected]"}Output
{
"id": 1,
"name": "Alice",
"email": "[email protected]"
}Input
{"user":{"id":1,"address":{"city":"Bangalore","zip":"560001"}}}Output
{
"user": {
"id": 1,
"address": {
"city": "Bangalore",
"zip": "560001"
}
}
}Input
[{"id":1,"name":"Alice"},{"id":2,"name":"Bob"}]Output
[
{ "id": 1, "name": "Alice" },
{ "id": 2, "name": "Bob" }
]Frequently Asked Questions
What makes JSON invalid?
Common JSON errors include: trailing commas after the last item, single quotes instead of double quotes, unquoted keys, undefined or NaN values, and comments (JSON does not support comments).
Does this validator store my JSON?
No. Validation and formatting happen in your browser. Your data is never sent to our servers unless you explicitly use the API convert endpoint.
Can I validate JSON from an API response?
Yes. Paste the raw response body and the validator will check it and reformat it with proper indentation.
What is the difference between JSON validation and JSON formatting?
Validation checks whether the input is syntactically correct JSON. Formatting (pretty-printing) takes valid JSON and adds consistent indentation and newlines for readability. DevConvert does both in one step.