JSON Validator
Check whether JSON is valid and see exactly where it breaks.
Runs entirely in your browser.
Your data never leaves this device and is never sent to our servers.
Result
A JSON validator answers one question: will a parser accept this document? If it will not, you need the position of the problem, not a generic failure. This tool gives you both, plus the shape of the root value once it parses.
How to use it
- Paste the JSON you want to check.
- Read the result — valid documents report the root type and how many top-level entries they contain.
- If it is invalid, the message names what the parser objected to.
Not working as you expect? Report a problem with this tool.
Frequently asked questions
What counts as valid JSON?
Double-quoted keys and strings, no trailing commas, no comments, and no single quotes. JSON is stricter than JavaScript object syntax, which is the usual source of surprise.
Does it validate against a schema?
No. This checks syntax only. Validating against a JSON Schema is a different job and needs the schema supplied alongside the document.