Security & Web • Published August 17, 2026

cURL with Proxies: How to Route HTTP, HTTPS, SOCKS5 & Authenticated Proxies

Master proxy configuration in cURL. Learn how to route requests through HTTP, HTTPS, and SOCKS5 proxies (-x), authenticate with -U, and configure environment variables.

Complete guide to configuring proxy routing in cURL. Learn how to connect through HTTP/HTTPS proxies, SOCKS5 tunnels with remote DNS resolution, proxy authentication, and environment variables.

Frequently Asked Questions

Q1. What is the difference between socks5:// and socks5h:// in cURL?

With socks5://, your local machine resolves the domain name into an IP address via local DNS before connecting through the proxy. With socks5h://, the hostname is passed to the proxy server to resolve remotely, preventing DNS leaks and bypassing local DNS firewalls.

Q2. How do I test my public IP address through a cURL proxy?

Run: curl -x http://proxy.example.com:8080 https://api.ipify.org?format=json. The returned IP should match the proxy server instead of your local machine.

Q3. How do I ignore environment proxy variables in cURL?

Pass --noproxy "" or empty proxy flag: curl --noproxy "" https://example.com.

Q4. Can I route cURL requests through the Tor network?

Yes. If Tor is running locally on port 9050, run: curl --socks5-hostname 127.0.0.1:9050 https://check.torproject.org/api/ip.