Most of the time, when you open a website, your computer talks directly to the web server on the other end. But there are times you might want it to take a detour. That’s where proxy servers can help.
Proxies came out of the need to organize large, chaotic computer systems, though their use has morphed toward privacy needs. They’re a useful tool in certain situations, but they have clear strengths and limitations. Here’s what you need to know about proxy servers, from what they are and how they work, to why you might want to use one and a look at the different types available.
What is a proxy server?
The US National Institute of Standards and Technology, or NIST, defines a proxy server as “a server that services the requests of its clients by forwarding those requests to other servers.”
In layman’s terms, a proxy server is a middle layer between you and the internet. When you visit a website or use an internet-connected app, your device sends a request to that app or site’s web server. When you use a proxy server, your request doesn’t go straight to the site, but instead takes a detour through the proxy. The proxy reaches out, gets the page, sends it back to you and shows its own public IP address instead of yours in the process. It’s like a front desk at an office: You hand over the request, the desk delivers it and brings back the reply. So, the office sees the desk, not you.
Proxy servers can help people stay private, give companies a way to manage bandwidth and keep networks safe from unwanted visitors.
How does a proxy server work?
The basic choreography of a proxy is to take a request, deliver it to the site, wait for the reply and then pass the reply back to you.
From your point of view, nothing feels different from normal internet use. But from the website’s point of view, the request came from the proxy, not you. That’s because the proxy uses its own IP address.
To break it down:
- Your device sends a request to the proxy server.
- The proxy forwards that request.
- The site answers back to the proxy.
- The proxy hands that answer over to you.
Proxies can be physical boxes that sit between your network and the internet, or they can be cloud-based services you connect to. Getting one going usually means adding the proxy’s IP and port to your settings. Most systems have a quick setup script to do it for you, but you can also punch the details into your device’s network settings yourself if you like (for example, Wi-Fi/Ethernet > Proxy).
Why people use proxies (and why you might want to)
Proxies solve a handful of real-world problems. For starters, they give you a bit of privacy by acting as a barrier between your computer and the rest of the internet. That means the proxy swaps in its own IP while keeping yours hidden, and can filter requests (but it doesn’t automatically encrypt the connection). Therefore, it may be harder for sites, advertisers or anyone else to keep tabs on what you’re doing. Not impossible, but harder.
And then there’s access. A proxy can make it look like you’re logging in from a different location, which comes in handy if something is blocked where you are, like a website or an app. So, you can use a proxy server to access region-restricted streaming content, such as international Netflix libraries. Companies also lean on proxies to help manage heavy traffic and give remote employees a safer way to connect.
In workplaces and schools, proxies are generally used to keep people on task. They can block certain sites and track how the internet is being used. They can also speed things up by caching pages that lots of people visit. That way, the same content doesn’t have to be downloaded over and over. Some proxy servers — more specifically, reverse proxies — can screen out suspicious traffic and keep your network from being too easy to poke at.
All of this makes a proxy server a pretty practical tool.
Proxy servers don’t deliver foolproof privacy, and you may want to avoid free proxy server services
Like with VPNs, you get what you pay for, so for the most part, you’ll want to pay for a reliable proxy service. Free proxies are typically slow, unreliable and often exist less to help you than to harvest whatever data you send through them.
Plenty of services also keep logs. Companies are building records of where you go online — information that can be sold off or handed over if someone asks. If you want to keep your online activity private, check for a no-logs policy.
Encryption is another weak link. Most proxies don’t bother with it, which means your traffic is out in the open unless it’s being encrypted over the HTTPS protocol (i.e. URLs that start with «https»). Accordingly, because most proxies lack encryption, they can’t prevent your data from being intercepted and read by attackers.
Even if none of that happens, performance with free/public proxies and crowded shared IPs is sometimes shaky. The extra hop adds latency, and a shared proxy can drag your connection down to a crawl. While they’ll hide your public IP address, that’s about where the protection ends. The idea of total anonymity through a proxy is mostly an illusion.
You should almost never use a “free” proxy. A well-provisioned paid or enterprise proxy will usually fare better.
The proxy zoo
There’s no single, catch-all version of a proxy. Forward proxies are the most common, but there are plenty of others designed for more specific jobs.
| Type | What it does | When it’s used |
|---|---|---|
| Forward proxy | Takes user requests and sends them out to the internet | Offices, schools or homes where one gateway controls access |
| Reverse proxy | Manages traffic before it hits a web server | Large sites to balance traffic and add security |
| Transparent proxy | Shows your IP and makes it clear that a proxy is in use | Often set up in schools or workplaces for monitoring and caching |
| Anonymous proxy | Hides your public IP address but still admits it’s a proxy | People who want some privacy without going off the grid |
| Elite proxy | Hides both your IP and the fact you’re using a proxy | Stronger privacy or to get around IP- or region-based blocks |
| Residential proxy | Uses IPs from real devices at real addresses; is a physical box at a specific location rather than a server in a datacenter | Ad testing, avoiding detection or browsing as a “regular” user |
| Datacenter proxy | Runs from commercial servers instead of ISPs | Fast and cheap, good for large tasks like web scraping and price and inventory monitoring |
| Public proxy | Free and open for anyone | Easy to find, but may be overloaded and unreliable |
| Shared proxy | An IP address used by multiple people at once | A budget option with some trade-offs in speed and trust |
| SSL proxy | Encrypts traffic between you and the proxy | Adds extra encryption when browsing |
| Rotating proxy | Assigns a new IP for each request or session | Frequent use in web scraping or avoiding detection |
| SOCKS proxy | Works with all kinds of traffic, not just web requests | Situations where performance is paramount, like gaming, streaming or peer-to-peer connections; bypassing firewalls or network restrictions |
| Tor/Onion proxy | Routes data through several encrypted relays | Strong pseudo-anonymity and censorship resistance |
| DNS proxy | Handles and sometimes caches DNS lookups | Speeds up site access and filters unwanted domains |
| Mobile proxy | Sends traffic through real mobile devices | Checking mobile ads or simulating mobile users |
Proxy vs. VPN vs. NAT: What’s the difference?
People tend to throw proxies, VPNs and Network Address Translation — or NAT — into the same bucket, but they’re different. They just all happen to live in the middle of your connection and the internet at large.
A proxy hides your public IP address and puts its own out there instead. That buys you some basic privacy and sometimes a way around content blocks, but most proxies stop there. They don’t encrypt what you’re sending, so if your web traffic is intercepted by a bad actor, that data can be easily read. Accordingly, you’ll want to have a multi-part cybersecurity approach, including a password manager and antivirus software (there are great free antivirus programs, so you don’t even need to pay).
A VPN takes the proxy idea and adds encryption for robust privacy protection. It hides your public IP address, but it also wraps all your web traffic in encryption, which scrambles the data. That makes it a lot harder for outsiders to read your internet activity or grab sensitive details.
NAT is the odd one out. It’s built into routers and isn’t about privacy or encryption at all. It’s the behind-the-scenes feature that lets a whole household or office full of devices share one public IP address. It works quietly at the network layer, just translating addresses so everything can talk to the internet without stepping on each other. Each device on your home internet network has a private IP address, which is sort of like a street address, and each of these is different, meaning your phone has a different private IP than your laptop. Because a public IP address is assigned to your network as a whole, all gadgets connected to your router have the same public IP address. NAT translates your devices’ private IP addresses to a public IP address, essentially enabling anything on your home network to be able to access the internet at large.
Proxy servers, VPNs and NAT all have to do with IP addresses, which is the common factor, but VPNs and proxy servers can be used to mask IP addresses, whereas NAT is simply about how IP addresses are assigned.
A proxy server can be a handy tool in your app arsenal, but remember that it’s a limited one
Proxies are useful because they can hide your public IP address, let you access certain types of content and cut down on tracking, but they won’t make you untouchable. Anyone expecting total privacy, security or anonymity from a proxy is asking too much.
The point is to see proxies for what they are: one tool in your kit. They’re good at some jobs and bad at others. If you use them with clear expectations, they’ll do their part. But don’t use a wrench when you need a hammer. And don’t use a proxy service when you need encryption — use a VPN instead.