Validate JSON syntax online for free. Instantly detects errors and pinpoints the exact line and character of syntax problems. Free JSON syntax checker.
Paste your JSON into tools.arkaserve.com/json-validator — valid JSON shows a green confirmation instantly, invalid JSON shows the exact line and character of the error. This is faster than running your application to catch a parse error. Common issues caught: trailing commas, single-quoted strings, comments (not allowed in JSON), and mismatched brackets. Completely free, no signup.
The most frequent JSON errors are: trailing commas after the last item in an array or object, using single quotes instead of double quotes around keys and strings, including JavaScript-style comments (// or /* */), unescaped backslashes inside strings, and missing or extra closing braces/brackets. The validator pinpoints the exact location of each error.
Yes, completely free — no account, no character limit for typical JSON sizes, and no daily limit. Works in your browser without sending data to a server. Paste, validate, fix — as many times as needed.