How it works
Three simple steps — all in your browser.
1
Open it in your browser
JSON validator runs entirely on your device — no upload, no account, and nothing to install.
2
Do the work
Validate, format and minify JSON. Everything happens instantly as you go.
3
Save your result
Download or copy the output straight away. Your data never leaves your device.
Why use JSON validator
Completely private
JSON validator works locally in your browser — your files and text are never sent to a server.
Free, with no account
No sign-up, no trial, and no usage limits. Open the tool and start straight away.
Works on any device
Runs in any modern browser on desktop, tablet or phone — nothing to download.
Frequent questions
Is JSON validator free to use?
Yes — every tool here is completely free, with no account, sign-up, or usage limits.
Is anything uploaded to a server?
No. JSON validator runs entirely in your browser, so your data never leaves your device.
Do I need to install anything?
No. It works in any modern browser on desktop or mobile — there is nothing to download or install.
Does it work offline?
Once the page has loaded, the processing happens locally, so it keeps working even on a flaky connection.
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