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Here at PCMag, we cover a lot of security tools here that we hope you're using, like antivirus software and VPNs. But there are lesser-known protection methods you should know about, including proxy servers. Proxies used to be an easy way to anonymize yourself, but as VPNs became more popular and easier to use, proxies evolved and are now more widely used by businesses than individuals. We're here to tell you what proxy servers are, how they work, and who actually needs one.
This article was made possible in part by Webshare. It was written and edited independently without partner oversight.
What a Proxy Server Actually Does (and Why It Matters)
In short, a proxy server sits between you and the rest of the internet, acting as a "proxy" for your traffic. Without a proxy, your computer or mobile device requests traffic directly from the web, as it would using a standard connection. Adding a proxy server routes your request through an external server before sending it to the website or service you're connecting to. It adds one degree of separation between you and the site or service you want to connect with.
Here's how it works. Say, for example, that you want to search for something on Google. On a non-proxied connection, your PC would make a data request directly to Google's servers, which would then send the data back to your PC. When connecting via a proxy server, that request is passed through an external server and sent to Google. From there, the requested information is sent back through the proxy and finally to your PC.
This added layer of traffic routing is used for a variety of reasons, including protecting your privacy and anonymity, or spoofing your location to access geo-restricted content on the web. Additionally, proxies come in several forms: residential proxies, which simulate at-home users, mobile proxies, which simulate smartphone users, and datacenter proxies, which simulate connections from businesses and other servers.
If that sounds familiar, it should: it's very similar to what VPNs do. But where VPNs generally protect entire devices and all their traffic, complete with encryption, proxies usually don't encrypt everything, support only a handful of connection types, and are typically web-only, which makes them leaner than VPNs but less focused on security and more on privacy. Although their approach to traffic routing may sound simple, proxies can be complex.
Forward Proxies: The Everyday Privacy Buffer
This is the most common type of proxy. Forward proxy servers work as we described above: your information request is forwarded to the proxy server, passes through a firewall, and is sent to the intended domain.
(Credit: H2g2bob/Wikipedia (Creative Commons))The domain then sends the information back to the proxy, which passes it to your device. Sometimes, the proxy server may already have the requested information cached in its database. If so, the request won't be forwarded to the domain; instead, the proxy server will deliver the data to your device directly from its own servers.
This can reduce request and data transfer times and add another layer of anonymity to your browsing experience since your IP address is never exposed to the web domain you're trying to connect to.
Reverse Proxies: The Hidden Layer Behind Big Websites
A reverse proxy server, sometimes called a surrogate proxy, works in the opposite direction from a forward proxy. Instead of a user requesting data from the internet, a reverse proxy passes requests from the internet to users in an internal network. Larger websites and content delivery networks are the most common customers of reverse proxies, and users generally access these via the open internet over unproxied connections.
(Credit: H2g2bob/Wikipedia (Creative Commons))Web domains and other companies often use reverse proxies to monitor or restrict access to specific servers or parts of the web that an organization wants to prevent you from seeing. They can also be used by websites to obfuscate the actual location of an origin server (e.g., a website that illegally streams NFL games) or to fend off DDoS attacks, enhancing security and platform stability.
There are a few dozen additional benefits to using reverse proxies with web servers, but we won't bog you down with every use case here, since web domains or backend internet services are the main users. The average user doesn’t need to know about them (unless you plan to run your own content servers, that is). More often than not, you won't be able to tell if a website or server uses a reverse proxy, as the results on the client side typically look the same as a non-proxied web domain either way.
The 3 Levels of Proxy Anonymity—Ranked and Explained
Typically, anonymous proxy servers are divided into three levels of privacy:
High Anonymity Proxy Server (Level 1)
These are proxy servers that anonymize your originating IP address and don't identify themselves to web domains as proxies. They also regularly cycle through refreshed IP blocks, making it difficult for third-party auditors to identify an anonymized IP as associated with a particular proxy service.
Anonymous Proxy Server (Level 2)
These proxy services change your destination IP address to that of the proxy server and also identify themselves as proxies to the web domain. These are the most common types of proxy servers on the web today.
Transparent Proxy Server (Level 3)
As the name suggests, transparent proxy servers don't anonymize a user's originating IP address and will reveal exactly where a traffic request is coming from. Companies and organizations often use these, typically for content moderation and user monitoring within given networks. Think public libraries, schools, and IT departments within larger corporations that want to ensure their networks aren't being used for viewing adult content, downloading particular files, or other objectionable purposes.
Behind the Scenes: The Protocols That Make Proxies Work
The complete list of protocols used by proxies is extensive. It can include anything from fringe options, such as session initiation protocols (SIP, used exclusively for telephone routing in large organizations), to Simple Mail Transfer Protocol (SMTP) proxies that run in the background of email servers to protect against phishing attacks or spam. For the sake of brevity, we’re only describing some of the more relevant protocols consumer-level proxies use.
HTTP Proxies: Fast, Simple—and Not Very Secure
HTTP proxies use the unsecured HTTP protocol to route user traffic requests/downloads, and they are generally configured by the browser or within a web-based interface. These are fast and free but will usually not allow you to connect to HTTPS-protected destinations, which make up a significant portion of the web in 2023.
HTTPS Proxies: Adding Encryption to the Mix
Also known as SSL proxies, these work like HTTP proxies but utilize the HTTPS protocol to encrypt your traffic and allow you to connect to HTTPS web domains protected by SSL certificates.
SOCKS Proxies: Flexible, Powerful, and App-Friendly
SOCKS proxies (short for SOCKets Secure) allow the transfer of data and traffic compatible with the SOCKS5 protocol. SOCKS5 protocols route your traffic through a third-party server via TCP.
DNS Proxies: Rerouting Requests at the Source
DNS proxies are common online, and they work by forwarding a DNS request from the user to a DNS-based web domain or server. DNS proxies often automatically select a proxy server to forward the user's request, and they may allow you to access web-based content that would otherwise be restricted on your network for one reason or another (think the Great Firewall of China).
Smart DNS Proxies: The Streaming Hack for Geo-Restricted Content
Smart DNS proxies allow you to spoof your geolocation by only diverting one part of your internet traffic, specifically, DNS requests.
These are useful if, for example, you're trying to spoof your location to stream content that would otherwise be blocked from the part of the world where your IP address is located. For instance, if you live in the US and are right in the middle of a season of your favorite show but travel to and connect from another country, you might find that the show is no longer available in that region. Using a proxy allows you to keep streaming your favorite content consistently, no matter where you are.
CGI Proxies: Browser-Based Access, No Setup Required
CGI-based proxies (Common Gateway Interface) are found in web-based proxy servers that allow you to use the proxy's features through your browser or internet client. Some proxies are embedded within applications, but CGI proxies work strictly from the web browser. These are useful if you're connected to a network or using a device that doesn't allow proxy configuration, as determined by an organization's internal networking permissions, say, on a public computer at a library or a company machine where you don't have administrative rights to install software.
When a Proxy Beats a VPN (and When It Doesn't)
After going through this guide, you might be asking yourself whether a VPN provides most of the benefits of a proxy service. The simple answer is yes—but more securely and with more features. As you might expect, though, that’s not the whole story.
There are some cases where a proxy may be a better option. If you only want to quickly spoof your IP address or protect your anonymity, a proxy server is a valid alternative to a VPN, and if you're a DIY enthusiast, you can even set one up yourself. VPNs usually need to be installed on your device and require administrator-level permissions to install the proper drivers. Conversely, many proxies can be used through nearly every compatible web browser, and most offer browser extensions that you can toggle on or off as needed.
However, most proxy services no longer target individual users. Most proxy customers are developers and large businesses that use them to conduct comparative research to see how their web services look and operate in different parts of the world, or to compare their platform with competitors'. Others use different types of proxies, such as residential IP addresses versus datacenter IP addresses, to test if their service works as well for users on their home wi-fi as it does for companies with speedy connections and high-bandwidth needs. And AI companies love proxy services for web scraping and data collection, because if one proxy IP address gets blocked by a company that detects what they're doing, they can quickly (and affordably) switch to another IP address and get back to scraping.
In fact, most proxy services don't sell monthly subscriptions or security packages; they sell IP addresses by the dozens or hundreds, in bulk, and charge for bandwidth. Individuals who use proxies today usually do so to get around platform restrictions, such as IP bans, or to buy high-demand items like event tickets, merch drops, or sneakers. Some even use them to snap up high-demand electronics from online retailers that may limit your availability by IP address.
For more on how these tools compare, check out our complete comparison between VPNs and proxy servers.
Chris Stobing contributed to this article.