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JSON Formatter & Validator

Paste JSON and choose Format, Minify or Validate. Invalid JSON reports the line and column where parsing stopped, so you can fix a missing comma or quote quickly. Optionally sort keys alphabetically at every level.

This tool runs in an isolated frame on tools.freetoolspro.com. Your files and inputs stay on your device, and advertising on this page cannot read them.

Standards

Parsing follows the JSON standard (RFC 8259) as implemented by your browser’s JSON.parse: no comments, trailing commas or single quotes. Very large integers lose precision beyond 2^53, as in JavaScript.

Privacy

Your text is processed by a Web Worker inside the isolated tools.freetoolspro.com frame. It is not uploaded, logged or shown to advertising scripts on this page, and it is gone when you close the tab.

Common questions

Can I paste API responses with secrets?

The data stays in your browser, but avoid sharing real credentials anywhere you do not need to.

Does it support JSON5 or comments?

No, only standard JSON.

Methodology reviewed 2026-10-27. Processing details and test approach.

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