string/format

JSON Formatter & Validator

The JSON Formatter & Validator parses JSON locally, returns pretty and minified output, and surfaces parse failures with line-aware hints. It is built for quick cleanup of API payloads, config snippets, and copied logs without sending data to a server.

Indent width

Status

Valid JSON

JSON input

Pretty JSON

{
  "name": "Toolsmith Hub",
  "features": [
    "format",
    "validate",
    "minify"
  ],
  "release": {
    "date": "2026-06-11",
    "live": true
  }
}

Minified JSON

{"name":"Toolsmith Hub","features":["format","validate","minify"],"release":{"date":"2026-06-11","live":true}}

Top-level type

Object

Top-level keys

3 keys

Byte length

110

How to use it

1. Paste JSON into the input area and adjust the indentation width when you want a specific pretty-print format.
2. Review the formatted and minified output panels, then copy the version that matches your next step.
3. If parsing fails, use the error summary and nearby snippet to fix the exact character or trailing comma issue.

Why this tool

A foundational developer utility that balances raw formatting with enough guidance to reduce copy-paste parse churn.

Core function: Format, validate, and minify JSON locally.

Unique angle: Explain parse failures with correction hints.

Examples

Copy-ready examples for common workflows

Normalize a copied API response

Input

{"user":{"id":12,"roles":["admin","ops"]}}

Output

Pretty JSON with consistent indentation plus a minified one-line payload for logs or fixtures.

Catch a trailing comma before commit

Input

{"name":"toolsmith",}

Output

A parse error with line and column plus a hint that trailing commas are not valid in strict JSON.

FAQ

Questions this page answers up front

Does the formatter keep key order?

Yes. It formats the parsed object as-is, so the existing property order is preserved unless the original source was already reordered elsewhere.

Can I use this for large payloads?

For normal debugging and config sizes, yes. Extremely large blobs are still parsed in the browser, so performance depends on the device.

Is any JSON sent to a backend?

No. Parsing and formatting happen entirely in the browser.