JSON Formatter & Validator
Format, validate, and minify JSON with an interactive tree view and instant error detection.
Comparing two versions? Use JSON Diff to compare files and API responses while ignoring formatting and object key order.
About JSON Formatter & Validator
This JSON Formatter helps developers quickly beautify messy or minified JSON into readable, indented output, or compress it down to a single minified line for production use. Paste any JSON — from an API response, config file, or log — and click Format to pretty-print it with 2-space indentation, or Minify to strip all whitespace. Switch to Tree view to explore deeply nested objects and arrays with collapsible nodes, which is often faster than scrolling through raw indented text for large payloads. If the JSON is invalid, the tool shows the exact parser error so you can locate and fix the problem quickly. All processing happens locally in your browser; nothing is uploaded anywhere.
Frequently Asked Questions
No, all formatting and validation happens entirely in your browser using JavaScript's built-in JSON parser. Nothing is sent to a server.
The error message comes directly from the browser's JSON parser and typically points to the position and type of syntax error, such as a missing comma or unquoted key.
Format (beautify) adds indentation and line breaks for readability. Minify removes all unnecessary whitespace to produce the smallest possible output, ideal for production payloads.
An interactive, collapsible view of your JSON's structure — click any object or array to expand or collapse it, which makes it much easier to navigate deeply nested data than scrolling through indented text.