How fast is the check?

It runs as you paste or type, with no button to click - the status updates instantly.

What does it tell me if my JSON is invalid?

The exact line and column of the first problem, plus a plain-English description of what's wrong, not just a generic parser error.

Can it fix the JSON too, not just check it?

Yes - the Repair button on the same page runs a separate repair pass that fixes common broken-JSON cases automatically.

Is the JSON I check sent to a server?

No. Checking runs entirely in your browser - nothing is uploaded to our servers.

Jsontify

Ad-free, fast, private JSON viewer & editor

Paste JSON, drop a file, or Open

Explorer

Tree explorer will appear here once JSON is loaded

Inspector

Select a node to inspect it

JSON Checker

Paste JSON and Jsontify checks it the moment you stop typing - a green status means it's valid, ready to use as-is; a red status means something is wrong, with the exact line and column of the first problem shown immediately instead of a generic 'invalid JSON' message.

This is built for the fast, everyday check: pasting an API response to confirm it actually came back well-formed, checking a config snippet before you save it, or confirming a value someone sent you in chat is real JSON before you spend time debugging around it.

If the check comes back invalid, you don't have to go hunting through a wall of text by eye - a 'Go to error' button jumps the editor straight to the offending character, and the Repair tool on the same page can usually fix the common cases (trailing commas, missing quotes) in one click if you just need working JSON rather than a diagnosis.

The check runs in a background worker, so pasting a large response to check its shape stays fast, and the content is processed in your browser - nothing is uploaded to our servers.

Frequently asked questions

How fast is the check?: It runs as you paste or type, with no button to click - the status updates instantly.
What does it tell me if my JSON is invalid?: The exact line and column of the first problem, plus a plain-English description of what's wrong, not just a generic parser error.
Can it fix the JSON too, not just check it?: Yes - the Repair button on the same page runs a separate repair pass that fixes common broken-JSON cases automatically.
Is the JSON I check sent to a server?: No. Checking runs entirely in your browser - nothing is uploaded to our servers.