Wondering how websites detect whether you're using a VPN? Several techniques are used to detect connections made over VPN.

IP blacklist:
The anti-VPN mechanism mainly works by checking the visitor's IP address against a blacklist of known VPN addresses. Since VPNs typically use known data centers to host their servers, it's not difficult to determine the IP ranges they own.

Detect internal fraud:
Large companies with lots of resources like Google and Netflix are in a unique position to detect proxies due to the amount of traffic they handle. Even if a VPN service offers dozens of IP addresses, chances are they still show up multiple times among their millions of users, allowing companies to easily flag suspicious IPs.
These businesses have significant engineering talent at their disposal, so their solutions may also use advanced technologies such as machine learning to analyze and classify traffic patterns.

How to avoid being blocked:
While there's no surefire way to always beat these mechanisms, there are some steps you can take to improve your chances.
Try different IP addresses
Many commercial VPN providers give you access to multiple servers spread across different data centers around the world. By switching to another server, you change the IP address of your internet connection.

If you are blocked, browse available servers. If you're lucky, you might find one that's not on the site's blacklist.

Notify websites about your VPN usage:
It can be helpful to notify certain websites that you use a VPN. For example, if you contact your bank's customer service department, they may be able to put a note on your account to help resolve any issues if your VPN use is compromised by their anti-fraud system. Flagged.

This is an especially good idea if you've previously connected to the service without a VPN but plan to start using it in the near future, perhaps due to travel. Remember that sites often limit traffic through proxies to limit bot abuse, not because they have a specific bias against VPN users.

Pay for a private IP address:
The more people using a particular IP, the more likely it is to be blacklisted at some point. Having a private IP address makes it much easier to use your VPN undetected.
Luckily, most reputable VPN providers offer dedicated IPs, albeit often at a premium price. You should invest in one if you frequently find yourself blocked by your favorite websites.

Using a VPN is less common:
Another way to avoid more crowded servers is to use a lesser-known VPN provider. Since certain companies tend to dominate the market, you can expect them to appear prominently on the blacklist. A more obscure VPN may be less likely to be blocked or trigger a CAPTCHA.

Of course, this doesn't mean you should use the cheapest, shadiest supplier you can find. You especially want to avoid free VPN services. Not only do these sites often have thousands or millions of users, but they are also magnets for fraud, copyright infringement, and other problematic behavior. Websites have strong incentives to target them for blocking.

Tinker with your browser:
In some cases, specific browser features or settings may trigger protection systems. For example, Google is more likely to provide CAPTCHAs if you use your browser's private browsing mode in conjunction with a VPN. Turning this off will reduce your chances of encountering them.