---
title: "JSON Formatter and Validator | formformform"
description: "Validate, format and minify JSON with useful syntax error locations. Runs entirely in your browser."
url: "https://www.formformform.com/tools/json-formatter-validator"
type: static
generatedAt: "2026-08-23T18:56:58.727Z"
---
# JSON formatter and validator

Validate, pretty-print or minify JSON with precise syntax errors and a tree-friendly result.

Paste JSON to validate it, format it for reading, or minify it for transport. Parse errors include a useful location and the data never leaves this page.

## Real parsing

The browser JSON parser validates strings, escapes, numbers, arrays and objects.

## Format or minify

Readable two-space indentation and compact output come from the same parsed value.

## Local by design

Sensitive configuration and response data are not uploaded.

## Frequently asked questions

Does it accept comments?

No. Comments and trailing commas are not valid JSON.

Will it alter values?

No, although insignificant whitespace is rewritten.

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## Want the form to collect the answers too?

Hand-written HTML still needs somewhere to post to. formformform gives you the form, the hosting, the responses and the notifications — free while we are in early access.

[Start free](https://app.formformform.com/register?utm_source=landing&utm_medium=bottom&utm_campaign=tools&utm_content=json-formatter-validator)