How to Use Proxies

Read your proxy line

Proxy providers usually hand out proxies as a line of four values separated by colons:

host:port:username:password

The host and port tell your tool where to connect, username and password authenticate you. Many tools want the same data as one URL, such as http://username:password@host:port or socks5://username:password@host:port.

Step 1: pick the right proxy

Choose residential or mobile proxies for rotating IPs billed per GB, or ISP proxies for static IPs. In the generator you also choose the country, rotating or sticky sessions and HTTP or SOCKS5.

Step 2: test it

Before you use a proxy in production, confirm that it works and exits where you expect. The free proxy checker shows the exit IP, geo and latency. From a terminal:

curl -x http://USERNAME:PASSWORD@HOST:PORT https://api.ipify.org

Step 3: use it where you need it

• Browser: use the proxy settings of the browser or an extension. See how to set up a proxy for Windows, macOS, Firefox and phones.
• Python: pass the proxy URL to requests, httpx or Scrapy.
• Headless browsers: Playwright and Puppeteer accept a proxy server and credentials at launch.
• Apps: if the app has a proxy setting, enter host, port and credentials. SOCKS5 is the more general option, see SOCKS5 proxies.

A Python example

import requests

proxy = 'http://USERNAME:PASSWORD@HOST:PORT'
r = requests.get(
    'https://api.ipify.org',
    proxies={'http': proxy, 'https': proxy},
    timeout=30,
)
print(r.text)  # the proxy's exit IP

Rotating or sticky?

Use rotating lines when each request is independent, such as scraping search results or product pages. Use sticky lines when a session must keep the same IP, such as logging into an account. Read more in rotating proxies.

Common mistakes

• Using a rotating line for a login flow and wondering why sessions drop.
• Forgetting that proxy traffic is billed: large images and videos use up GB quickly.
• Mixing countries within one account, which can trigger security checks.
• Not setting timeouts and retries in scripts.
• Sending sensitive data over plain HTTP. Use HTTPS.