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JSON Validator

Check whether JSON is valid and find the exact position of syntax errors.

About JSON Validator

Validate JSON against the strict RFC 8259 grammar. When the document is invalid, the validator highlights the line and column where parsing failed and explains the most likely cause, so you can fix configuration files and API payloads quickly.

How it works

  1. 1

    Paste JSON or drop a file into the editor.

  2. 2

    Validation runs automatically as you type.

  3. 3

    Fix the highlighted line, or format the valid result with one click.

Frequently asked questions

Which JSON standard is used?

Strict JSON as defined in RFC 8259 and ECMA-404 — the same rules as JSON.parse in every browser.

Does it support JSON with comments (JSONC)?

No, comments are not valid JSON. The validator detects them and tells you where they are so you can remove them.

Does it validate JSON Schema?

This tool validates syntax. It also reports basic statistics such as depth, number of keys and array lengths.