JSON Formatter & Validator

What is JSON Formatter & Validator?

A JSON formatter turns compact or messy JSON into clean, indented text that is easy to read, and a JSON validator tells you whether the text is valid JSON at all. This tool does both in one place: paste your JSON, see immediately whether it is valid, and format it with two spaces, four spaces or tabs, or minify it to the smallest possible size.

When your JSON has a mistake, the tool shows the problem in plain language together with the exact line and column, and highlights that line in the editor. Typical issues it catches include trailing commas, single quotes instead of double quotes, unquoted property names, comments, unclosed brackets and invalid escape sequences.

Everything runs locally in your browser. Your JSON is never uploaded, which makes this a safe place to inspect API responses, configuration files and payloads that contain tokens or personal data. The formatter also keeps your data exactly as written: long numbers such as 12345678901234567890, numbers like 1.0 and duplicate keys are not rounded, rewritten or dropped.

How to use

1. Paste your JSON into the input box, or click Load sample to try an example.
2. Watch the status line: it says Valid JSON, or shows the error with its line and column.
3. Choose an indentation (2 spaces, 4 spaces or tab) and click Format, or press Ctrl/Cmd + Enter.
4. Click Minify if you want the smallest single-line version instead.
5. Use Copy to copy the result, or Download .json to save it as a file.

Example

{"name":"Toolsy","tags":["json","formatter"],"free":true}

{
  "name": "Toolsy",
  "tags": [
    "json",
    "formatter"
  ],
  "free": true
}