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ToolSMA

JSON Formatter & Validator

Paste JSON to pretty-print it with your choice of indentation, validate it with precise error locations, or minify it for production. Optionally sort keys alphabetically.

How to use the JSON Formatter & Validator

  1. Paste your JSON.
  2. Click Format, Minify or Validate.
  3. Copy or download the result.

Common JSON errors

Trailing commas, single quotes instead of double quotes, unquoted keys and comments are not allowed in standard JSON. The validator shows the line and column of the first error.

Frequently asked questions

Is my JSON sent to a server?

No. Parsing and formatting use your browser's built-in JSON engine.

How big a file can I format?

Several megabytes work fine on modern devices.