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JSON Formatter

Format, minify, and validate JSON with ease.

What the JSON Formatter does

This tool helps you work with JSON data in three ways: it prettifies messy or minified JSON into a clean, indented layout; it minifies JSON by stripping all unnecessary whitespace to make payloads as small as possible; and it validates JSON to tell you instantly whether the text parses correctly. Formatting uses two-space indentation so nested objects and arrays are easy to scan.

It is aimed at developers and anyone who deals with API responses, configuration files, or log output. Whether you are debugging a request body, preparing a compact payload, or just trying to make a wall of text readable, the formatter gives you a fast, no-setup way to do it.

How to use it

Paste your JSON into the input box. Click Format / Prettify to produce an indented version, Minify to collapse it to a single compact line, or Validate to check whether the input is well-formed JSON. The result, or a confirmation that the JSON is valid, appears in the output box below.

If your JSON contains a syntax error, the tool shows the exact parser message, including where the problem occurs, in a red error box so you can quickly locate and fix issues like a trailing comma or a missing quote. Use the Copy button to grab the output, or Clear to reset both boxes and start over.

Tips and notes

Validation and formatting rely on the browser's native JSON parser, so the rules match exactly what a JavaScript application would accept: keys must be double-quoted, trailing commas are not allowed, and comments are not permitted. If a value fails to parse, check those common pitfalls first.

All processing happens locally in your browser. Your JSON is never transmitted to a server, so you can safely format or validate data that contains tokens, credentials, or other sensitive fields.

Frequently Asked Questions

What is the difference between Format and Minify?▼
Format / Prettify expands your JSON with two-space indentation and line breaks for readability. Minify removes all unnecessary whitespace to produce the smallest possible single-line output, which is ideal for transmitting payloads.
How does validation work?▼
The tool parses your input with the browser's native JSON parser. If it parses successfully you see a confirmation; if not, the exact error message is shown so you can find the problem.
Why does my JSON show an error?▼
Common causes are trailing commas, single quotes instead of double quotes, unquoted keys, or comments, none of which are valid JSON. The error box shows the parser message to help you pinpoint the issue.
Is my data sent anywhere?▼
No. Formatting, minifying, and validating all happen entirely in your browser, so your JSON never leaves your device.
Is there a size limit?▼
There is no fixed limit imposed by the tool, but very large documents depend on your browser's available memory since all processing is done client-side.
Is it free?▼
Yes, the JSON Formatter is completely free to use with no sign-up or installation.

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