Quick Answers

What Is Port 3128?

Port 3128 is the default listening port of Squid, the open-source caching proxy, so it is a common port for HTTP proxies.

By Team of Monkeys Editorial Updated 1 min read Affiliate disclosure

This guide contains affiliate links to Geonode, Webshare and Rayobyte. If you buy through them we may earn a commission, at no extra cost to you.

What Is Port 3128 illustration: port 3128 is the default listening port of Squid, the open-source caching proxy, so it is a common port for HTTP proxies 3jdej38j4

The short answer

Port 3128 is the default port of Squid, a widely used open-source caching proxy. Because so many company and hobby proxies run Squid, host:3128 has become shorthand for "HTTP proxy".

What it means for you

Treat a :3128 proxy as an HTTP proxy that also tunnels HTTPS via CONNECT. If you run your own Squid, change the default port and require authentication, because scanners constantly probe 3128 looking for open proxies.

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Also known as

Squid port, default Squid HTTP port.

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Affiliate disclosure: Team of Monkeys is an affiliate of Geonode, Webshare and Rayobyte. Links and banners marked as sponsored, and links to Geonode, Webshare and Rayobyte in the text, use our referral links, and we may earn a commission if you buy through them, at no extra cost to you. Our explanations and comparisons are written to be useful whichever provider you choose.

Editorial note: Proxy providers change their pools, features and prices often, so treat any figures here as typical ranges at the time of writing and confirm current terms with the provider before you buy.
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