JSON formatter

Parse JSON locally, verify its syntax, and produce stable indentation for reading, review, or reuse.

Local processing
Local processing
Ready — nothing leaves this page
Input
Settings
Run tool

Browser memory only. No upload fallback.

Result
Your result will appear here

The input stays available if you need to adjust a setting.

How to use json formatter

  1. 1

    Paste JSON.

  2. 2

    Choose indentation.

  3. 3

    Format, then copy or download the result.

A realistic example

Expand a compact API response into two-space-indented JSON for debugging.

Supported formats and limits

Input and output: UTF-8 JSON text.

  • JSON comments and trailing commas are invalid.
  • Very large documents may consume noticeable browser memory.

Questions people ask

Does formatting change values?

No. It parses and serializes the same JSON data with new whitespace.

Can it format JSON5?

No. V1 follows standard JSON syntax.