JSON Formatter and Validator
Paste your JSON below to format, minify or validate the syntax.
What is JSON and what is this tool for?
JSON (JavaScript Object Notation) is a lightweight data-interchange format, widely used in REST APIs, configuration files and communication between services. Its syntax is readable by humans and easily parsed by machines — which has made it the de facto standard for structured data on the web.
This tool allows three main operations directly in your browser:
- Format (pretty-print): adds line breaks and configurable indentation (2 spaces, 4 spaces or tab), making the JSON readable for debugging and code review.
- Minify: removes spaces, line breaks and unnecessary characters, reducing payload size before saving or transmitting.
- Validate syntax: identifies formatting errors — unclosed braces, trailing commas, missing quotes — and displays the parser's error message with the approximate position of the problem.
Frequently Asked Questions (FAQ)
What is the difference between formatting and minifying?
Formatting adds indentation and line breaks to make it easier for humans to read. Minifying does the opposite: it produces a compact string, with no extra spaces, ideal for production (smaller payload size, lower bandwidth usage).
What does a JSON syntax error mean?
A syntax error means the text does not follow the rules of the JSON format. Common causes: using single quotes instead of double quotes, including a trailing comma after the last item in an object or array, leaving braces/brackets unmatched, or including comments (JSON does not support comments, unlike JavaScript).
Can I use tab as indentation?
Yes. Select the Tab option in the indent selector before clicking Format. Choosing between spaces and tab is a team preference — the resulting JSON is equally valid with either option.
Does the tool support very large JSON?
Yes, within the browser's memory limits. For very large files (above a few megabytes), processing may be slower. No artificial size limit is imposed by the tool.