POST JSON data using cURL

David Y.

The Problem

How do I send a POST request containing JSON data using cURL?

I have tried the following request:

curl -X POST \
  -d '{"user_id": 1, "verified": true}' \
  https://example.com/api/method
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However, this returns an HTTP 415 Unsupported Media Type error.

The Solution

Most web endpoints that accept JSON data will expect to receive requests with the Content-Type: application/json header. By default, cURL adds the header Content-Type: application/x-www-form-urlencoded when data is provided with a request. Therefore, we need to manually specify this header in our cURL request using the -H/--header flag:

curl -X POST \
  -H "Content-Type: application/json" \
  -d '{"user_id": 1, "verified": true}' \
  https://example.com/api/method
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More information about cURL can be found by perusing its manual page, which is accessible on the cURL website or through the command man curl.