How to set up a proxy in Firefox

Firefox can keep its own proxy settings instead of inheriting the system defaults, which makes it useful when you want one browser isolated on a different route.

Set the proxy at the system or browser level

1. Open Settings, scroll to Network Settings, and click Settings….
2. Choose Manual proxy configuration, then enter the host and port for HTTP, HTTPS or SOCKS as required by the provider.
3. Save, reload your tabs, and clear any assumptions by testing a fresh request rather than a cached page.

Verify the IP changed

Firefox-specific settings make it easy to compare proxied and non-proxied browsers side by side, but they also make it easy to forget which profile is using which route. Then open My IP and confirm the public IP, ASN and country now match the proxy you expected.

Verify the proxy is actually working

Use the headers test to confirm whether Firefox is really leaving through the configured proxy and whether that endpoint behaves as transparent, anonymous or elite. Run Proxy Headers for a single endpoint or paste several rows into the bulk proxy checker to confirm status, anonymity and exit location.

Next checks

Keep this verification loop handy: My IP to confirm the exit address, Proxy Headers to catch leaks, and Bulk Proxy Checker when you need to compare multiple endpoints.