JSON Formatter & Validator | Format, Minify, Validate
Beautify or minify JSON with 2/4-space indentation and real-time validation that pinpoints exact line/column errors. Fast, private, and 100% in-browser.
How to Use This Tool
- 1
Choose Format (beautify) or Minify.
- 2
Paste or type JSON into the input area.
- 3
See live validation with exact line/column errors—or use Manual mode.
- 4
Pick indentation (2 or 4 spaces) and apply.
- 5
Copy or download the processed result.
Use Cases & Examples
Debug REST API & GraphQL Responses
Pretty-print or minify API/GraphQL responses to inspect structure and troubleshoot quickly.
Validate Configuration Files
Validate package.json, tsconfig.json, and other config files with precise error locations.
Code Review & Documentation
Reformat compact JSON for readable pull requests and documentation snippets.
Minify JSON for Production
Minify JSON to reduce payload size and bandwidth while preserving data exactly.
JSON & Validation Basics
JSON is a UTF-8 text format composed of objects and arrays; allowed types are string, number, boolean, null, object, and array.
RFC 8259 rules: double-quoted keys/strings, escaped control characters, and no trailing commas.
Parsing follows the standard to surface exact error locations; pretty-print/minify run in O(n) relative to input size.
Frequently Asked Questions
Q.What's the difference between JSON and JavaScript objects?
A. JSON is a text data format with a fixed set of types (string, number, boolean, null, object, array). JavaScript objects are runtime structures and can include functions, undefined, Symbols, etc.
Q.Can I use single quotes in JSON?
A. No. Per RFC 8259, keys and string values must use double quotes (").
Q.Are trailing commas allowed in JSON?
A. No. Valid JSON does not allow trailing commas after the last item of an array or object.
Q.Can this tool handle very large JSON files?
A. Yes—within browser memory limits. Modern devices typically handle several megabytes smoothly; switch to Manual mode for very large inputs.
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