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JSON Formatter

JSON formatter tool. Enter JSON data using either text input or file upload, and get formatted JSON. Supports files up to 100KB in size.

JSON Data (Text Input)
Result
Read Only

How to use

About this tool

Formats or minifies JSON, with syntax checking and highlighting.

How to use

Paste JSON or load from file; choose indent type and size; format or minify.

Options

Indent: Space / Tab / None (minify). When using Space, choose 2, 4, 6, or 8. "None" produces a single-line minified JSON.

Use cases

• Readable API responses • Formatted config files • Log JSON • Minification for deployment

Code Examples

JavaScript
Read Only
1JSON.stringify(obj, null, 2);  // format
2JSON.stringify(obj);        // minify
Python
Read Only
1import json
2json.dumps(obj, indent=2)
3json.dumps(obj)
PHP
Read Only
1json_encode($obj, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE);
2json_encode($obj);

Privacy and data

Formatting is done locally in the browser; JSON is not sent to a server.

FAQ

Q: What is the valid range for conversion?
A: Standard Roman numerals range from 1 (I) to 3999 (MMMCMXCIX). Numbers outside this range cannot be expressed in classical Roman notation.
Q: Why does 4 become IV instead of IIII?
A: Roman numerals use the subtractive notation: when a smaller value precedes a larger one, the smaller is subtracted. IV means 5 − 1 = 4. This convention has been standard since medieval times.
Q: Can I convert Roman numerals back to Arabic numbers?
A: Yes. Enter Roman numerals (e.g., XIV) and the tool outputs the corresponding Arabic number (14).
Q: Are lowercase roman numerals accepted?
A: Yes. Lowercase input (e.g., xiv) is accepted and treated the same as uppercase.
Q: Does this tool send my data to a server?
A: No. All conversion is performed in the browser. No data is sent to any server.