About JSON Formatter
Format, validate and minify JSON locally with a readable editor, syntax validation and downloadable output.
Format and validate JSON
JSON Formatter accepts JSON text and checks its syntax before formatting or minifying it. When the browser's JSON parser reports a syntax error, the tool surfaces the error and can identify the relevant line when the parser provides a character position.
Formatting is useful for reading nested objects and arrays. Minifying removes unnecessary whitespace when a compact representation is needed for a request, configuration or saved file.
Designed for local developer work
The text you paste into the formatter is processed locally in the browser. The tool also applies resource limits so extremely large or deeply nested input cannot grow without bound and freeze the browser.
Because JSON can contain credentials, API responses and other sensitive data, check the content before pasting it into any online service. With this tool, the intended formatting path does not require sending the JSON to a My Karya Kit processing server.
When it helps
Use it when an API response is hard to read, a configuration file needs validation, or a compact JSON payload is required for storage or transfer. For tabular data, CSV ↔ JSON can be more convenient; for visual inspection, JSON Viewer provides a structured view.