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JSON Formatter & Validator

Q: What makes this different from just eyeballing the JSON?

When JSON is invalid, this tool reports the exact line and column where parsing failed, not just a generic error.

Q: Is my data uploaded anywhere?

No, parsing and formatting happen directly in the browser.

Paste any JSON to pretty-print it and check it's valid — if something's wrong, you'll get the exact line and column, not just "invalid JSON."

Paste JSON here

Upload File

Result

No signup · No file limits · Files never leave your device

How It Works

Paste or Upload

Paste JSON directly, or upload a .json file.

Format or Minify

Pretty-print with indentation, or strip it down to one compact line.

Fix or Download

If it's invalid, you'll see exactly which line and column to check. If it's valid, download the result.

Frequently Asked Questions

What makes this different from just eyeballing the JSON?

When JSON is invalid, this tool tells you the exact line and column where parsing failed, rather than just "Unexpected token" with no location — so you know exactly where to look.

Is my data uploaded anywhere?

No. Parsing and formatting happen directly in your browser using the same JSON engine built into it — nothing you paste or upload ever leaves your device.

Is this free?

Yes, completely free with no daily limit.