Sending data — POST requests

GET fetches. POST creates. Learn to send data to a server.

⏱ Est. ~5 min

01 · Read

So far you've only used GET — asking a server for data. But you also need to send data: create users, submit forms, post comments.

That's what POST is for.

In curl: - -X POST sets the method to POST - -H "Content-Type: application/json" tells the server what format you're sending - -d '{...}' is the request body — the data you want to send

Key points

GET = read. POST = create.
-X POST switches the HTTP method
-d '{...}' sends a JSON body
Always add Content-Type: application/json when sending JSON

02 · Code example

Here's the structure of a POST request in curl.

POST with JSON body

curl -X POST https://api.example.com/todos \
  -H "Content-Type: application/json" \
  -d '{"text": "Learn curl", "done": false}'

Line by line: -X POST — use the POST method instead of GET -H "Content-Type: application/json" — tells the server the body is JSON -d '...' — the body data (use single quotes so the shell doesn't escape the double quotes inside)

03 · Terminal exercise

First, GET the current todo list to see what's in it.

(This section is interactive — please enable JavaScript.)

04 · Terminal exercise

Now POST a new todo to the server. Send it as a JSON body.

(This section is interactive — please enable JavaScript.)

05 · Fill in the blank

To specify an HTTP method in curl, use the _____ flag.

06 · Quiz

You want to add a new product to an e-commerce API. The API docs say POST /api/products. Which curl command is correct?

curl https://shop.com/api/products?name=Shoes&price=50
curl -X POST https://shop.com/api/products -H "Content-Type: application/json" -d '{"name":"Shoes","price":50}'
curl -GET https://shop.com/api/products -d '{"name":"Shoes"}'
curl --create https://shop.com/api/products -body '{"name":"Shoes"}'

Other lessons in this chapter

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