curl

The command-line tool for making HTTP requests.

Backend Engineer · Junior Frontend Engineer · Junior Data Engineer · Junior

Also known as: cURL, curl command

curl is a command-line tool for making requests to a URL. It’s the quickest way to try an API, check a response or debug a network problem, from any terminal.

curl https://api.example.com/users/42                  # a GET request

curl -i https://example.com                            # include response headers
curl -v https://example.com                            # verbose: shows the whole exchange
curl -s https://api.example.com/status | jq .          # silent; pipe JSON to jq

curl -X POST https://api.example.com/orders \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $TOKEN" \
  -d '{"item_id": 7, "quantity": 2}'                   # POST with a JSON body

curl -L http://example.com                             # follow redirects
curl -o page.html https://example.com                  # save to a file
curl -fsS https://example.com/health                   # fail on HTTP errors, quiet, but show errors
curl -w "%{http_code} %{time_total}s\n" -o /dev/null -s https://example.com   # status and timing

Flags worth knowing

Flag	Does
`-X METHOD`	sets the method
`-H`	adds a header
`-d`	sends a body (and implies POST)
`-i` / `-v`	shows headers / everything
`-L`	follows redirects
`-f`	exits non-zero on HTTP errors (useful in scripts)
`-u user:pass`	basic auth

Tips

Browser requests as curl: DevTools can copy any request as a curl command (network tab).
Quote the URL when it contains & or ?, or the shell will misread it.
Don’t paste tokens into shared shells or history. Use an environment variable.
A 200 with an error body isn’t an error to curl. Check the response.
For a visual or saved-collection workflow, see HTTP client tools.