ConfigManual

🧾 JSON Formatter & Validator

Beautify, minify, and validate JSON. Everything runs locally in your browser.

Indent:
{
  "name": "ConfigManual",
  "tags": [
    "linux",
    "networking"
  ],
  "active": true
}

What this tool does

Paste any JSON and this tool instantly validates it, beautifies it with clean indentation, or minifies it to a single line. If the JSON is malformed, you get the exact error message so you can find the problem fast. Everything happens in your browser — your data is never sent to a server.

Common uses

  • Debugging API responses — make a wall of minified JSON readable.
  • Validating config files — catch a missing comma or bracket before it breaks a deploy.
  • Minifying for production — strip whitespace to shrink payloads.

Quick JSON tips

  • Keys and strings must use double quotes, never single quotes.
  • No trailing commas after the last element.
  • Allowed value types: string, number, boolean, null, object, array.

Working with APIs? You might also like our Base64 & hash toolkit.

Frequently asked questions

Why does my JSON say it's invalid?

The usual culprits are a trailing comma after the last item, single quotes instead of double quotes, a missing bracket or brace, or unescaped characters inside a string. This tool points to the exact position of the error so you can jump straight to it instead of hunting line by line.

What's the difference between beautify and minify?

Beautify adds indentation and line breaks so JSON is easy for humans to read — ideal when debugging. Minify strips every unnecessary space and newline to make the payload as small as possible — ideal for production, where smaller responses load faster.

Is my data private?

Yes. Formatting, validating, and minifying all happen locally in your browser. Nothing you paste is transmitted to a server, so it's safe to use with internal API responses or config files.

Can JSON have comments?

Standard JSON does not allow comments or trailing commas. If you need those, you're likely looking at a relaxed variant like JSON5 or JSONC — convert or strip the extras before using strict JSON parsers, which will otherwise reject the file.