Learn everything about HTTP headers in cURL. Master adding custom headers with -H, inspecting response headers with -i/-I, dumping headers to disk, setting User-Agents, and cookie handling.
Frequently Asked Questions
Q1. How do I add multiple headers in a single cURL command?
Provide multiple -H flags: curl -H "Header1: Value1" -H "Header2: Value2" https://api.example.com.
Q2. How do I spoof or change the User-Agent in cURL?
Use the -A or --user-agent flag: curl -A "Mozilla/5.0 (Windows NT 10.0; Win64; x64)" https://example.com.
Q3. How do I send and receive cookies with cURL headers?
Use -b "name=value" or -b cookies.txt to send cookies, and -c cookies.txt to write received cookies from Set-Cookie headers into a jar file.
Q4. How do I test CORS headers with cURL?
Send an Origin header: curl -I -H "Origin: https://app.devtooladda.com" -H "Access-Control-Request-Method: POST" -X OPTIONS https://api.example.com.