How to use
01
Paste the suspect JSON
Drop the payload into the input pane, or click Try sample to see a passing example first. Config files, API responses, and hand-edited fixtures are the usual suspects.
02
Press Validate
The tool attempts a strict parse. A valid document reports its type, array or object, plus its size in characters. A broken one reports where parsing failed.
03
Fix and re-run
Jump to the reported position, correct the comma, quote, or bracket, and validate again. Use Clear when you want to start over with a fresh payload.
Why JSON Validator
- Paste your JSON and check valid JSON in one click. As a strict json validator it reports the line and position where the json data invalid, not just a vague failure.
- Everything runs in your browser. Your data never leaves your device, so you can validate private or client payloads safely.
- It does more than pass or fail. Working as a json validator and corrector, it points you at the exact character that breaks parsing so the fix is quick.
- Need to read or tidy the structure too? Pair it with the JSON Formatter when you want a json beautifier online or an online json viewer.
- Free with no limit. Use this online validator as often as you need, with no sign up.
Common questions
Why does a trailing comma make JSON invalid?
JavaScript tolerates a comma after the last element, but the JSON spec (RFC 8259) doesn't, so {"a":1,} fails. It's the single most common reason hand-edited JSON breaks. The validator reports the position of the offending character so you can delete it and move on.
What does the validator report when my JSON passes?
You get a confirmation plus two useful facts: the top-level type, meaning array or object or a primitive, and the size in characters. The type check catches a subtle bug where an endpoint suddenly returns an object wrapper instead of the bare array your code expects.
Is this a schema validator as well?
No. It checks that the document is well formed, not that it matches a contract. A schema validator or a json schema validator compares data against field definitions, which is a separate job. Do this syntax check first, since schema validation is meaningless on JSON that doesn't parse.
How is validating different from using a json formatter online?
Both parse your input, but they answer different questions. Validation is pass or fail with a reason; formatting rewrites whitespace for readability. If you want a json formatter and validator flow, validate here to isolate the error, then beautify once it parses. Keeping the steps separate makes the error loop faster.
What about exploring the data like an online json viewer?
Not on this page; the output is a verdict, not a tree. If you're after an online json viewer or a json file viewer, run the document through a beautifier once it validates, and the indented output becomes easy to scan. This page stays focused on the pass or fail answer.
Is jsonvalidator with no space the same thing?
Yes. Whether you type jsonvalidator as one word, JSON lint, or JSON checker, the task is identical: run a strict parse and report the first failure. Different names, one operation.
Can validated JSON go into Excel from here?
Not directly, but it's a two-step path. Once your document passes, run it through the JSON to CSV tool, which works as a json to excel converter; Excel and Google Sheets open the resulting CSV without any importer. Validating first saves you from debugging a conversion that failed on bad syntax.
Should I validate before or after beautifying?
Validate first. A json beautifier online has to parse anyway, but its purpose is presentation, so the tighter loop is: validate, fix the reported spot, repeat, then pretty-print the clean result. On files someone edited by hand, expect two or three rounds.