JSON Formatter
JSON Validation & Formatting: Validates JSON syntax and converts it to a readable format or compresses it.
Standard: RFC 8259 - The JavaScript Object Notation (JSON) Data Interchange Format (December 2017)
The JSON Formatter formats compact JSON into a human-readable form and helps find JSON syntax errors. All processing happens in your browser; no data is sent to servers.
How to Use
- 1
Choose Format or Minify mode.
- 2
In Live mode (default), processing happens automatically as you type. Switch to Manual mode to process on button click.
- 3
Paste your JSON into the input area; it will be validated and formatted automatically.
- 4
In Format mode, select indent size (2 or 4 spaces).
- 5
Copy the result or download it as a JSON file.
Use Cases
Debug API Responses
Pretty-print compressed REST/GraphQL responses to understand the data structure.
Validate JSON Files
Find and fix JSON syntax errors in configuration or data files with clear error locations.
Code Review
Format compact JSON to improve readability during code reviews.
Minify JSON
Remove whitespace and line breaks to reduce file size and bandwidth.
What is JSON?
JSON (JavaScript Object Notation) is a lightweight data interchange format that is easy for humans to read and write, and easy for machines to parse and generate.
Two structures: Object (name/value pairs) and Array (ordered list of values).
Data types: string, number, boolean, null, object, array.
JSON is language-independent and supported by most programming languages.
RFC 8259 (December 2017): The latest JSON standard. Keys must use double quotes, trailing commas are not allowed, and strings must be UTF-8 encoded.
Frequently Asked Questions (FAQ)
Q.Is my data safe?
A. Yes. All processing happens in your browser. No data is sent or stored.
Q.Difference between JSON and JavaScript objects?
A. JSON is text and requires quoted keys; JS objects are real in-code objects with optional quotes.
Q.Can I use single quotes?
A. No. JSON requires double quotes (" ").
Q.Are trailing commas allowed?
A. No. Trailing commas are not allowed in JSON arrays or objects.
Q.Can it handle very large files?
A. Within browser memory limits. Files larger than 1MB may take longer.
Q.Difference between format and minify?
A. Format improves readability; minify removes whitespace to reduce size.
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