JSON Validator
Checks whether the input parses as valid JSON and reports the error if not. Free, instant and 100% private in your browser.
Developer Tools Runs in your browser
What does JSON Validator do?
Checks whether the input parses as valid JSON and reports the error if not. Paste your json on the left and NMSnabbit instantly shows the result on the right. For example, “{"a":1}” gives “Valid JSON”. Everything runs locally in your browser — nothing is uploaded, so it stays private and works offline. You can process several values at once and copy the result with one click.
How to use the JSON Validator
- 1 Type or paste your json into the input box.
- 2 The result appears instantly in the output box as you type.
- 3 Tip: try the example “{"a":1}” to see “Valid JSON”.
- 4 Click “Copy output” to copy the result.
What you can use it for
- Quickly checks whether the input parses as valid json and reports the error if not without installing anything.
- Checking results while learning or teaching how json and result relate.
- Preparing or debugging data for programming, electronics or homework.
- Working privately when the data shouldn't be uploaded to a server.
Frequently asked questions
How do I use JSON Validator?
Paste your json into the input field above. JSON Validator runs instantly in your browser and shows the result on the right — no button to press and nothing uploaded.
Is JSON Validator free and private?
Yes. JSON Validator is completely free with no sign-up, and it runs entirely client-side in your browser, so your data never leaves your device.
Can I process more than one value at once?
Yes. Enter several values separated by spaces or new lines and each one is handled independently, so you can batch-process in a single pass.
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