Question 1

How do I validate JSON online?

Accepted Answer

Paste your JSON into the editor above and it is validated instantly as you type. If the JSON is valid you'll see a green confirmation; if it's invalid, the tool points to the exact line and position of the first syntax error so you can fix it quickly.

Question 2

What makes JSON invalid?

Accepted Answer

The most common JSON syntax errors are trailing commas after the last item, single quotes instead of double quotes, unquoted property names, missing commas between items, and comments (JSON does not support comments). JavaScript object literals allow these, but strict JSON does not.

Question 3

Can I convert a JavaScript object to valid JSON?

Accepted Answer

Yes — just click Beautify. If your input isn't strict JSON, Beautify converts the JavaScript object literal automatically: keys get double quotes, single-quoted and backtick strings become double-quoted, trailing commas and comments are removed, functions and undefined values are dropped, and NaN or Infinity become null — the same rules JSON.stringify uses. The conversion is a safe parser; your pasted code is never executed.

Question 4

What is the difference between validating and beautifying JSON?

Accepted Answer

Validating checks that your JSON follows the official syntax rules and reports any errors. Beautifying (also called formatting or pretty-printing) re-indents valid JSON with consistent spacing and line breaks so it's easy to read. This tool does both: it validates as you type and formats on demand.

Question 5

How do I fix an "Unexpected token" error in JSON?

Accepted Answer

An "Unexpected token" error means the parser hit a character it didn't expect — usually a trailing comma, a single quote, a missing quote around a key, or a stray bracket. Paste the JSON into this validator: it highlights the line and column of the error so you can spot the offending character.

Question 6

Can I minify JSON with this tool?

Accepted Answer

Yes. Click the Minify button to strip all whitespace and line breaks from valid JSON, producing the smallest possible output — useful for API payloads, config files, and reducing file size.

Question 7

Is it safe to paste sensitive JSON here?

Accepted Answer

Yes. Everything runs locally in your browser using JavaScript — your JSON is never uploaded, stored, or sent to any server. You can even disconnect from the internet and the tool keeps working.

JSON Validator & Beautifier

JSON VALIDATOR & BEAUTIFIER FAQ