Does this JSON validator upload my data?

No. JSON validation runs locally in your browser. Nothing is sent to a server.

How is this different from the JSON formatter?

This page only checks JSON syntax. The JSON formatter can also pretty-print and minify. Both share the same local parser.

Most invalid JSON includes a location. If the browser and the fallback locator cannot find one, you still get a clear message without a stack trace.

Data

Validate JSON and see clear error locations. Runs entirely in your browser.

LocalProcessed locally — your JSON never leaves your browser.

JSONSyntax check only

Paste or type JSON to get started. Validation does not change your input.

1. Paste the JSON to check
Put the JSON into the input area. Use Paste or Load example. Validation runs in your browser.
2. Validate
Choose Validate, or press Ctrl+Enter / Cmd+Enter. The JSON validator reports whether the syntax is valid.
3. Read the result
Valid JSON is confirmed clearly. Invalid JSON shows a readable error and, when possible, the line and column.

Valid JSON
{"ok":true,"items":[1,2]} is valid. The validator confirms it without changing your input.
Trailing comma
{"name":"Ada",} is invalid JSON. The error includes a line and column so you can find the extra comma.

Does this JSON validator upload my data?: No. JSON validation runs locally in your browser. Nothing is sent to a server.
How is this different from the JSON formatter?: This page only checks JSON syntax. The JSON formatter can also pretty-print and minify. Both share the same local parser.
What if the error has no line number?: Most invalid JSON includes a location. If the browser and the fallback locator cannot find one, you still get a clear message without a stack trace.

Data
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