JSON Formatter, Validator & Minifier
Pretty print, minify, and validate JSON for API responses, config files, logs, and test fixtures without sending the text to a server.
A JSON formatter parses valid JSON and rewrites it with readable indentation.
Use minify when you need compact JSON, and format when you need to inspect nested data.
Use standard JSON
Wrap keys in double quotes and remove comments or trailing commas before validating.
Keep huge payloads local
For very large files, a local editor or command-line formatter may be faster than a browser page.
Formatted output uses two-space indentation. Minified output removes whitespace that is not part of string values.
Validation follows the browser JSON parser, so comments, trailing commas, and unquoted object keys are rejected.
This tool is useful for small and medium API payloads, webhook examples, config snippets, and logs that you want to inspect quickly.
For very large files, a local editor or command-line formatter may be more comfortable.
Example
Paste an API response, format it with indentation, then copy the cleaned result into a ticket, doc, or test fixture.
Assumption
Input should be valid JSON, not JavaScript object literal syntax.
Limitation
The browser must hold the full text in memory, so very large JSON files can feel slow on older devices.
API debugging
Pretty print response bodies, webhook payloads, and request examples.
Config cleanup
Validate app config snippets before pasting them into docs or test files.
Fixture prep
Minify or format JSON fixtures for tests, examples, and seed data.
Log inspection
Make nested JSON logs easier to scan when debugging local issues.
Does the JSON formatter keep my data private?
Yes. The conversion runs locally in your browser and does not need a backend.
Can I format JSON with comments?
No. Comments are not valid standard JSON, so the validator rejects them.
What indentation does it use?
Formatted output uses two spaces, which is common for API examples and documentation.
Can I use it for API debugging?
Yes. It is a quick fit for pasted responses, request bodies, webhook payloads, and config snippets.
Suggested workflow
JSON cleanup path
Move from conversion or pasted API data to formatted, inspected, and export-ready JSON.