What is the most common JSON syntax error?

Trailing commas after the last item in an array or object. Standard JSON does not allow trailing commas, though some parsers are lenient.

Can it validate JSON Schema?

This tool validates JSON syntax only. For JSON Schema validation, you will need a dedicated schema validator.

Is there a size limit?

JSON up to 1 MB can be validated. For larger files, consider validating sections separately.

JSON Validator

Validate JSON and get a formatted, pretty-printed version or a detailed error with line number.

Text input

About JSON Validator

Validate JSON and get a formatted, pretty-printed version or a detailed error with line number. Powered by JustUse.me — free, ad-free, and private. This tool runs entirely in your browser. Your files are never uploaded to any server.

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