// mime type · application type

application/json

JSON data · .json

What application/json is

application/json is the standard type for JSON — the default for most REST APIs. Setting it on a request body tells the server to parse JSON; a mismatched type is a common cause of 400 and 415 errors.

How it's used

You'll see this as a Content-Type value on requests and responses — for example Content-Type: application/json. It's the type associated with the .json file extension. Application types cover structured data and binary formats — from JSON and XML to PDFs, archives, and Office documents.

Other application types