curl

Send a basic GET request.

curl URL

Save the response to a file.

curl -o output_file URL

Save using the filename from the URL.

curl -O URL

Follow redirects.

curl -L URL

Send form data via a POST request.

curl -X POST -d "key=value&key2=value2" URL

Send JSON via a POST request.

curl -X POST -H "Content-Type: application/json" -d '{"key":"value"}' URL

Add a header.

curl -H "Authorization: Bearer token" URL

Option	Description
-o file	Saves the response body to the specified file.
-O	Saves the file to the current directory using the filename from the URL.
-L	Follows redirects (301/302).
-s	Runs in silent mode, suppressing progress and error output.
-S	Used with -s to show errors only.
-w "%{http_code}"	Appends formatted output such as the HTTP status code.
-X method	Specifies the HTTP method (GET, POST, PUT, DELETE, etc.).
-H "header"	Adds a request header.
-d "data"	Specifies the body data for a POST request.
-F "field=value"	Sends data as multipart/form-data.
-u user:password	Specifies credentials for Basic authentication.
-I	Retrieves response headers only (HEAD request).
-v	Shows detailed request/response information (for debugging).
--max-time seconds	Sets the timeout duration.
-k	Skips SSL certificate verification (for development environments).

Sends a simple GET request. The response body is printed to standard output.

curl https://api.example.com/users/1
{"id":1,"name":"Alice","email":"alice@example.com"}

Checks only the HTTP status code. The -s option enables silent mode, and -o /dev/null discards the response body.

curl -s -o /dev/null -w "%{http_code}" https://example.com
200

Inspects the response headers (uses -I to send a HEAD request).

curl -I https://example.com
HTTP/2 200
content-type: text/html; charset=UTF-8
content-length: 12345
last-modified: Thu, 01 Jan 2026 00:00:00 GMT

Sends JSON data via POST with Bearer token authentication.

post_json.sh

curl -s -X POST \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer my_token_here" \
  -d '{"name":"Alice","age":30}' \
  https://api.example.com/users

bash post_json.sh
{"id":42,"name":"Alice","age":30,"created_at":"2026-03-06"}

Downloads a file. -L follows redirects, and -sS shows errors only.

curl -sSL -o /tmp/file.tar.gz https://example.com/release.tar.gz

Uploads a file (multipart/form-data).

curl -F "file=@report.pdf" -F "title=Report" https://example.com/upload

Accesses a resource using Basic authentication.

curl -u admin:password https://example.com/admin/api

Stores the response in a variable for further processing.

fetch_user.sh

response=$(curl -s https://api.example.com/users/1)
echo "$response" | grep "name"

bash fetch_user.sh
  "name": "Alice",

When using curl in scripts, combining -s (silent) and -S (show errors) as -sS is a common pattern. It is also common to use -w "%{http_code}" to check the status code and handle any response other than 200 as an error.

Only use -k (skip SSL verification) in development environments — never in production. For downloading files, wget is also a handy option.