Format unreadable JSON into clean indented output, minify it back down, and get precise error messages with line numbers when the syntax is invalid. Nothing is ever sent to a server.
Getting started
Paste your JSON — a raw API response, a config file or a log line — into the input.
Choose an indent width of two or four spaces, or switch to minified output.
Valid JSON is formatted immediately; invalid JSON reports the exact position of the problem.
Copy the formatted result or download it as a .json file.
Why it helps
Turns a single-line API response into something you can actually read and navigate.
Error messages point to the specific character position, so trailing commas and missing brackets are found in seconds.
Minification strips every unnecessary byte for production payloads.
Runs entirely in your browser, so response bodies containing tokens or customer data never leave your machine.
In practice
Reading an API response captured from a browser network panel or a curl request.
Validating a configuration file before committing it and breaking a build.
Reducing payload size by minifying JSON served to clients.
Inspecting a webhook body while debugging an integration.
Everything people ask most about the json formatter & validator, answered plainly.
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