Port 80

What Does Port 80 Mean?

Port 80 is the port number assigned to commonly used internet communication protocol, Hypertext Transfer Protocol (HTTP). It is the default network port used to send and receive unencrypted web pages.


When a client attempts to connect to a server and make a request, it needs to know both the server’s IP address and which network service will be used to transfer data. To make it convenient for programmers, most popular network services are assigned “well-known” port numbers by default. This strategy began back in 1991 when Tim Berners-Lee’s original specification for HTTP stated that if there was no port assigned to an HTTP connection, Port 80 should be used.

Today, most websites use HTTPS, a more secure version of the HTTP protocol that uses port 443. Port 443 allows data transmission over an encrypted network, while Port 80 enables data transmission in plain text.

Some of the Well-Known Port Numbers Internet Protocol
80 HTTP (Hypertext Transfer Protocol)
443 HTTPS (Hypertext Transfer Protocol Secure)
530 RPC (Remote Procedure Call)
21 FTP (File Transfer Protocol)
23 Telenet
53 DNS (Domain Name System)
22 SSH (Secure Shell)
25 SMTP (Simple Mail Transfer Protocol)
194 IRC (Internet Relay Chat)

Techopedia Explains Port 80

Port 80 and Cybersecurity

Although some cybersecurity experts suggest that closing port 80 can help with system protection, others believe that port 80 should be kept open. Proponents of enabling this port point out that it’s helpful in redirecting traffic from HTTP to HTTPS.

They may also ask the planner in question to “think about the browser on the other end” in the sense that the counterparty’s system may not be set up for a closed port 80 calibration.

Also, in terms of cybersecurity, experts may point out that closing port 80 will not stop man in the middle attacks from occurring, or prevent SQL injection and other types of attacks that rely on infiltrating a system through an Internet connection.

Port 80 Connection Problems

In some cases, an ISP may block port 80, making it difficult to get Internet access from a piece of hardware. Another common issue is an error that declares that port 80 is already in use.

In some ways, both these problems have been largely alleviated by the rise of cloud services. To the extent that multiple applications work over an Internet browser, they can all use the same port at once.

For example, Skype was one of the previous culprits for taking port 80 away from other applications. Using Skype through a browser eliminates that type of issue.


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Margaret Rouse

Margaret Rouse is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical, business audience. Over the past twenty years her explanations have appeared on TechTarget websites and she's been cited as an authority in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine and Discovery Magazine.Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages. If you have a suggestion for a new definition or how to improve a technical explanation, please email Margaret or contact her…