Format and Validate JSON Online

Format, minify, and validate JSON instantly. Runs entirely in your browser — nothing is sent to a server.

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What is Format and Validate JSON?
JSON (JavaScript Object Notation) is a lightweight, language-independent data interchange format defined in RFC 8259 and ECMA-404. It represents structured data as a tree of objects, arrays, strings, numbers, booleans, and null, and has become the default payload format for REST APIs, configuration files, and message queues. A JSON formatter (also called a beautifier or pretty-printer) parses raw JSON text and re-emits it with consistent indentation, line breaks, and key ordering so that nested structures become readable. A validator checks for syntax errors — missing commas, trailing commas, unquoted keys, mismatched brackets — and reports the line and character where parsing failed.
How to use
  1. Paste or type your JSON into the input field.
  2. Click Format to pretty-print or Minify to compress — validation runs automatically.
  3. Click Copy to copy the formatted or minified result to your clipboard.
Frequently asked questions
What is JSON formatting?
JSON formatting (or pretty-printing) adds indentation and line breaks to compact JSON so it becomes human-readable. This tool uses 2-space indentation by default.
How do I validate JSON?
Paste your JSON into the input field. The validator checks it in real time — a green checkmark means valid JSON, a red X means there is a syntax error. The error message shows exactly where the problem is.
What's the difference between formatting and minifying?
Formatting adds whitespace and indentation to make JSON readable. Minifying removes all unnecessary whitespace to reduce file size — useful for APIs and configuration files where size matters.
Why does my JSON show an error?
Common JSON errors include: missing or extra commas, unquoted keys, single quotes instead of double quotes, trailing commas after the last item, and unclosed brackets or braces. The error message indicates the position of the problem.
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