Proxy IP address and port: what they are and where to find them

A proxy IP address is the address of the intermediary server your requests pass through, and a proxy port is the number of the “door” on that server that leads to the proxy service. Together, the IP and port are written with a colon, for example 203.0.113.10:8080, and this is the pair you enter in your system, browser or app settings.

Below, we explain how to read these entries, which ports are the most common, where to find and enter a proxy address on a computer or phone, how to check the connection and what typical errors mean. All addresses in the examples are placeholders.

What is a proxy IP address and port

A proxy server acts as a middleman: an app sends its request not to the website but to the proxy, which forwards it on its own behalf. That’s why the site usually sees the proxy’s IP address rather than yours. To connect to this middleman, the app needs to know two things: where the server is and which of its services to contact.

The IP address answers the first question. In the familiar IPv4 format, it’s four numbers from 0 to 255 separated by dots, for example 203.0.113.10. Instead of an IP, you may be given a domain name like proxy.example.com: Windows, for instance, accepts either one in the address field.

The port answers the second. It’s a 16-bit number from 0 to 65,535: one server can run a website, email and a proxy at the same time, and the port tells the app which of these services to connect to. Numbers up to 1023 are system ports (80 is for HTTP, 443 for HTTPS), 1024 to 49,151 are registered ports, and 49,152 to 65,535 are dynamic ports.

How a proxy address is written

Proxy providers and apps write the same details in different ways. The main formats look like this:

203.0.113.10:8080
proxy.example.com:3128
socks5://203.0.113.10:1080
http://user:password@203.0.113.10:8080
203.0.113.10:8080:user:password
[2001:db8::10]:3128

• IP:port or domain:port is the basic format. In Windows, macOS and phone settings, the address and the port go into separate fields.
• A scheme before the address (http://, https://, socks4://, socks5://) indicates the proxy type. This is how you set a proxy in curl, for example, and in Chrome and Edge command-line options. In curl, the socks5h:// variant means that site names are resolved by the proxy itself rather than by your computer.
• A username and password before the @ are the sign-in details. Special characters in the password are encoded: @ becomes %40, and a colon becomes %3A. The URI standard, RFC 3986, calls a password in the string a deprecated practice, so don’t publish strings like these.
• IP:port:username:password is how some providers hand out the details, but it isn’t a standard. In system settings, you have to split this string into separate fields.
• An IPv6 address goes in square brackets; otherwise, the colons inside the address couldn’t be told apart from the colon before the port.

Common proxy ports

The port is chosen by whoever set up the server, so there’s no single correct number. But some numbers come up again and again, and each has its own story.

Port	Proxy type	Where the number comes from
80	HTTP	Standard HTTP port
8080	HTTP	“HTTP Alternate” in the IANA registry
3128	HTTP (Squid)	Squid’s default port
8888	HTTP	Port used by Fiddler and Tinyproxy
443	HTTPS (TLS to the proxy)	Standard HTTPS port
1080	SOCKS4, SOCKS5	SOCKS port per RFC 1928 and IANA
9050	SOCKS (Tor)	Tor’s default port

These are conventions, not rules. In a study of open proxies presented at the ACSAC conference in 2018, about 62% of working servers listened on ports 8080, 3128 or 20183. A proxy you buy can use any number, such as 10800 or 9989.

In the IANA registry, 3128 is actually assigned to a different service: it was Squid that made it the usual proxy port. So you can’t tell the proxy type from the port; check what your provider or administrator specified.

Proxy types: HTTP, HTTPS and SOCKS

An HTTP proxy handles web requests. It sees http:// pages in full, including forms and passwords, if the site doesn’t encrypt the connection. For https:// sites, the browser asks the proxy to open a tunnel to the right server and port with the CONNECT method, and encrypted data then travels through the tunnel: the proxy knows which site you connected to but can’t see the content.

Tunnels aren’t allowed to just any port: in its default configuration, Squid permits CONNECT only to port 443, and the HTTP specification (RFC 9110) recommends limiting CONNECT to known ports. Also, an HTTP proxy can pass your real IP to the site in the X-Forwarded-For or Forwarded header, so whether it hides your address depends on its configuration.

SOCKS4 is an old protocol for TCP connections: it can pass the destination address only as IPv4, and instead of a password it has just a username. The SOCKS4a extension added the ability to pass a domain name so that the proxy itself resolves it.

SOCKS5 is defined in RFC 1928 (1996): it carries TCP and UDP, understands IPv4, IPv6 and domain names, and supports username and password authentication. The standard port is 1080. Password authentication (RFC 1929) encrypts neither the traffic nor the password itself, which is sent in cleartext. And Chrome doesn’t support password authentication for SOCKS5 at all.

Where to find and enter a proxy address and port

If you bought a proxy, the address, port, type and sign-in details are in your account dashboard or in the provider’s email. At work, the administrator provides the settings; sometimes, instead of an address, you get a link to a proxy auto-config script (a PAC file), and then the address and port are written inside the script as a line like PROXY host:port. A proxy that’s already set up is visible in the same settings where you enter one.

Windows 11

1. Press Win + I and go to “Network & internet” → “Proxy.”
2. Under “Manual proxy setup,” next to “Use a proxy server,” select “Set up.”
3. Turn on “Use a proxy server,” fill in the “Proxy IP address” and “Port” fields, and select “Save.”

Once you save, browsers and apps that follow the Windows system settings will start using the proxy.

If “Automatically detect settings” or “Use setup script” is turned on, the proxy address may come from the network or from a script rather than from the manual fields. For a VPN connection, the proxy is set up separately, as Microsoft’s support article points out.

macOS

1. Choose Apple menu → “System Settings” → “Network.”
2. Select a connection, such as Wi-Fi, and click “Details.”
3. Click “Proxies” and turn on the type you need: “Web proxy (HTTP),” “Secure web proxy (HTTPS)” or “SOCKS proxy.”
4. Enter the server and port; if the proxy requires a username and password, turn on “Proxy server requires password.” Click “OK,” and the proxy will work for the selected connection.

You can also see the current proxy settings with this command in Terminal:

scutil --proxy

iPhone and iPad

1. Open “Settings” → “Wi-Fi” and tap the info button (i) next to the network you need.
2. At the bottom of the screen, tap “Configure Proxy” and select “Manual.”
3. Fill in “Server” and “Port.” If the proxy requires a username and password, turn on “Authentication” and enter them, then tap “Save.”

The setting is tied to a specific Wi-Fi network: on another network, you have to set it up again. This menu has no fields for a SOCKS proxy, only for an HTTP proxy.

Android

1. Open “Settings” → “Network & internet” → “Internet” and tap the network.
2. Tap “Edit” (the pencil icon) and open “Advanced options.”
3. Under “Proxy,” choose “Manual,” fill in “Proxy hostname” and “Proxy port,” and tap “Save.”

The proxy works while the phone is connected to that Wi-Fi network. These are the menu names on Google Pixel phones; on other brands, the path may differ. Android itself has a caveat: the HTTP proxy from the Wi-Fi settings is used by the browser, but other apps may not use it.

Chrome, Edge and Firefox

Chrome and Edge use the system settings by default. In Chrome, the path is “Settings” → “System” → “Open your computer’s proxy settings”; in Edge, it’s “System and performance” → “Open your computer’s proxy settings.” Both links open the system settings window in Windows or macOS.

Firefox can use its own settings. In version 152 and later, open “Settings” → “Privacy and security” → “Connection and software security” → “Advanced settings” → “Proxy settings” → “Configure proxy.” In versions before 152, this section is under “General.”

In the “Connection Settings” window, “Use system proxy settings” takes the proxy from the system, while “Manual proxy configuration” sets an address and port for Firefox only. If you’re choosing a browser for tasks like these, our comparison of browsers by speed and privacy will come in handy.

How to check that your proxy is working

Open any site that shows your public IP before and after turning on the proxy. If everything works, the second time you’ll see the proxy’s address instead of your own. With rotating proxy services, you connect through a gateway while traffic exits through other addresses, so the IP shown may not match the one you entered.

You can also check from the command line: curl is built into Windows 10 and 11. This command prints the IP that websites see when you connect through the proxy:

curl.exe -x http://203.0.113.10:3128 https://api.ipify.org

On macOS and Linux, type curl without the “.exe” part. For SOCKS5, change the scheme to socks5h://, and put the username and password before the address, separated from it by @.

What common errors mean

• ERR_PROXY_CONNECTION_FAILED in Chrome and Edge means the browser couldn’t connect to the proxy itself. On the error page, Chrome says: “There is something wrong with the proxy server, or the address is incorrect.” Check the IP and port, and make sure the server is running.
• ERR_TUNNEL_CONNECTION_FAILED means the proxy responded but didn’t open a tunnel to the site: for example, it doesn’t allow that port or can’t reach the server itself.
• 407 Proxy Authentication Required or a password prompt means the proxy requires a username and password. Enter the details you got from your provider or administrator.
• ERR_SOCKS_CONNECTION_FAILED means Chrome couldn’t set up a connection through the SOCKS proxy: the proxy didn’t complete the connection request, or it requires a username and password, which Chrome doesn’t support for SOCKS5.
• “The port you typed isn’t valid” on Android means there’s a typo or extra characters in the port field.
• Wrong proxy type: if a SOCKS proxy is entered in the HTTP field or vice versa, the connection won’t be established, because the protocols follow different rules for exchanging data.

Proxy vs. VPN: what’s the difference

A proxy changes the IP address for the apps that use it, but a regular HTTP or SOCKS proxy doesn’t encrypt the connection between you and the server. A VPN encrypts your device’s traffic all the way to the VPN server, from both the browser and apps, so on public Wi-Fi, outsiders can’t read or tamper with the data you send.

A proxy is a good fit when you need to change the address for a browser or a single app and don’t need encryption. To protect your whole device on networks you don’t control, you need a VPN.

Why free proxies are dangerous

Free proxies from public lists are the riskiest option. The authors of a study presented at ACSAC in 2018 tested more than 107,000 such proxies over 50 days: more than 92% didn’t respond at all. Among the working ones were servers that injected cryptocurrency-mining scripts into pages, swapped HTTPS certificates (1.06% of proxies that supported HTTPS) and added malicious code to downloaded .exe files (1.93% of proxies at least once).

A paper presented at the MADWeb workshop in 2024 painted a similar picture: of more than 640,000 free proxies collected over 30 months, only 34.5% were reachable at least once, and 16,923 servers modified page content. The authors conclude that free proxies pose serious risks to privacy and security.

Bottom line

A proxy IP address and port are the address of the intermediary server and the number of its service, and without the right port, the connection won’t work. Confirm the proxy type with your provider or administrator, enter the address and port in your system or browser settings, and check the result on an IP lookup site. To protect all your traffic, choose a VPN, and it’s best to avoid proxies from public lists.

Sources and methodology

Analysis of public sourcesChecked 21 September 2026

Versions

• Windows 11, build 26200
• Chrome 153, Edge 153
• Firefox 152
• macOS 13 Ventura and later

1. RFC 1928: SOCKS Protocol Version 5 rfc-editor.org
2. RFC 9110: HTTP, the CONNECT method and status code 407 rfc-editor.org
3. IANA port number registry iana.org
4. Microsoft: Use a proxy server in Windows support.microsoft.com
5. Mani et al., An Extensive Evaluation of the Internet’s Open Proxies (ACSAC 2018) arxiv.org

FAQ

What is a proxy port in simple terms?

It’s the number of the “door” on a server that leads to the proxy service. The IP address points to the server, and the port points to a specific program on it, so you need to enter both values.

What is the default proxy port?

There’s no single port. HTTP proxies most often run on 8080 or 3128 (Squid’s port), and SOCKS proxies on 1080. If you don’t specify a port, Chrome will use 80 for an HTTP proxy, and curl will use 1080.

Can you find out a proxy’s port from its IP address?

No. The server owner chooses the port, so it’s provided together with the address, in the provider’s account dashboard or by your administrator. A proxy that’s already set on a device is visible in the network settings.

How is SOCKS5 different from an HTTP proxy?

An HTTP proxy handles web requests, while SOCKS5 carries any TCP and UDP connections, so it also suits apps that have nothing to do with a browser. Regular HTTP and SOCKS5 proxies don’t encrypt the connection to themselves.

Why didn’t my IP address change after setting up a proxy?

The app may not be using the system proxy (for example, “No proxy” is selected in Firefox), or your phone may have switched from the Wi-Fi network the proxy is set for to mobile data. With rotating proxy services, the site will show the exit address, not the gateway’s.