JSON Validator
Paste JSON to validate it instantly. If it's invalid you'll see the line, column and a highlighted snippet pointing at the error. If it's valid you'll see structure stats: keys, depth and size.
Your JSON is parsed in your browser and never leaves your device.
How to use this json validator
- Paste your JSON into the input box.
- Validation runs as you type — a green banner means valid, red means invalid.
- If invalid, the error context shows the exact line and column with a caret pointing at the issue.
- If valid, review the document statistics (type, size, depth, keys) and copy the formatted output.
Frequently asked questions
How does this validator find the error location?
It runs the browser's native JSON.parse and reads the line, column or position from the parser error. The reported point is where the parser first noticed something invalid — the actual mistake is usually at or just before that spot.
What's the difference between validating and formatting JSON?
Validating only checks if the syntax is correct. Formatting (also called pretty-printing) re-prints valid JSON with indentation. Use the JSON Formatter for indenting and converting; this validator focuses on quickly finding errors.
Does it support JSON5, JSONC or comments?
No. It validates strict JSON only (RFC 8259). Trailing commas, single quotes and comments will be flagged as invalid.
Why does my JSON validate here but my API still rejects it?
Syntax validity and schema validity are different problems. This validator confirms the JSON parses; your API also expects specific keys, types and value ranges. A request body with an extra field, a missing required field, or a number where a string was expected will fail the API's schema check (often via JSON Schema or zod) even though the JSON is syntactically perfect.