JSON Formatter & Validator — Beautify or Minify JSON Online
Paste your JSON to instantly beautify, minify, or validate it. Errors are highlighted with line numbers so you can fix malformed data fast — no sign-up, no server upload.
Frequently Asked Questions
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. It is the standard format for REST APIs, configuration files, and data storage.
How do I validate JSON?
Paste your JSON into the input field and click Validate. The tool will parse the data and report whether it is valid. If there are syntax errors, you will see the error message and approximate line number so you can locate and fix the problem.
What is the difference between beautify and minify?
Beautifying adds indentation and line breaks to make JSON human-readable. Minifying removes all unnecessary whitespace, producing the smallest possible string — ideal for network transmission and storage.
Can I format large JSON files?
Yes. Because all processing happens in your browser, performance depends on your device. Most modern browsers handle files up to several megabytes without issues. For extremely large files (50 MB+), consider a desktop tool like our recommended developer utilities.
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