TirupatiTECHNOLOGIES
Developer Tools

JSON Validator

One missing quote or stray comma is enough to break an API call or crash a config file. This validator parses your JSON with the browser's strict JSON parser and tells you immediately whether it's valid — and if not, shows the exact error message and character position so you can fix it fast. Like all our developer tools, it runs entirely in your browser.

How it works

Validation is simply JSON.parse() in a protective wrapper:

  1. Your text is handed to the browser's built-in JSON parser — the same strict parser used by fetch() and Node.js.
  2. If parsing succeeds, the JSON is valid.
  3. If it throws, the error message is shown, and the reported character position is extracted so you know exactly where to look.

The parser enforces strict JSON: double-quoted strings, no trailing commas, no comments, no single quotes.

Worked example

Paste {"name": "Aarav", "city": "Dehradun",} and validate. You'll get an error like Unexpected token '}', ... is not valid JSON — the trailing comma after "Dehradun" is illegal. Remove it and the same input validates cleanly.

Understanding your results

Valid JSON means the text parsed without errors and is safe to send to an API or save as a config file. Invalid JSON shows the parser's error message plus the character position of the problem — count from the start of your text (position 0 is the first character) to find the culprit.

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Frequently asked questions

Strict JSON requires double quotes around all strings and keys, no trailing commas, no comments, and no single quotes. Values can be strings, numbers, booleans, null, arrays and objects — nothing else.

Content last reviewed on 2026-10-06.