What is this tool?

Paste JSON to format it with indentation, minify it into one line, or check whether it parses as valid JSON. The tool uses the browser’s JSON parser, so the output follows standard JSON behavior rather than a custom relaxed format.

The output area shows a line count for successful results, and invalid input shows the parser message with a line and column when the browser provides that position. This makes it useful for quick API response cleanup, configuration review, and validation before sharing a JSON snippet.

Common use cases

Reading minified API responses

Paste compact JSON from logs, API responses, or browser devtools and format it with 2 spaces, 4 spaces, or tabs.

Compacting JSON for config examples

Use Minify when you need a smaller one-line value for a fixture, environment variable, or documentation snippet.

Checking JSON syntax

Use the validity badge and error message to find malformed JSON before pasting it into another utility.

Comparing structured values

Format both versions of a JSON object before comparing fields manually, especially when nested arrays and objects are hard to read in one line.

How to Use

Paste JSON into the input area, or use Paste if browser clipboard access is available.
Choose Format or Minify.
For formatted output, choose 2 spaces, 4 spaces, or Tab indentation.
Use Copy to copy the output.

Notes / Limitations

This is a formatter and syntax validator. It does not validate against a JSON Schema or check whether field values are semantically correct.

Comments, trailing commas, and other JavaScript object literal syntax are rejected because they are not JSON.
Large inputs depend on your browser’s memory and responsiveness.
The Paste button may be blocked by browser permission rules; manual paste still works.

Privacy / local processing

Formatting, minifying, and validation run in the page with browser JavaScript. The JSON formatter code does not send the pasted JSON to a server.

What Is JSON?

JSON is a text data format made of objects, arrays, strings, numbers, booleans, and null. It is widely used for APIs, configuration files, logs, and test data because it is both human-readable and easy for software to parse.

Use the Base64 Encoder / Decoder when a JSON field contains an encoded value that you want to inspect.
Use the URL Encoder / Decoder when a JSON value needs to be safely placed inside a URL query parameter.
Use the Regex Tester when you need to test a pattern that will be stored in JSON.

JSON Formatter & Validator