VPN speed is affected by several factors, including the servers you choose and how many people are using your VPN service. We created this article to help explain these factors and help you get the best VPN speed when using Proton VPN.
If you want to know more about your internet speed and the different factors that can slow you down or speed you up, read our Latency, Bandwidth and Performance article.
To create a basic background, do the following:
Using a VPN means that your data is encrypted and decrypted on the client and server side, which takes processing power. This also means that your data has to travel a longer distance to reach the VPN server, which can cause delays (as discussed in the article above). So using a VPN will affect your internet speed, but the effect depends on factors such as how far you are from the VPN server, how busy the VPN server is, how far the VPN server is from the target website or other destination, and what VPN protocol you are using. Proton VPN also implements a performance-enhancing proxy (PEP) that significantly improves your internet speed when using our service.
We discuss each of these factors below.
Factors affecting VPN speed
The distance your data travels is the biggest factor affecting the speed of your internet connection. This is true whether you use a VPN or not, but a VPN increases your data throughput due to the extra distance to the VPN server. The reason that distance affects Internet speed is because the Internet is made up of countless individual networks that are interconnected. So, the longer your data has to travel, the harder it is to get through, increasing the risk of hitting obstacles along the way.
These barriers include:
- Add routers, switches, and networks that your data packets must pass through
- Congestion when you encounter routers that can even cause data packets to be lost
- The types of cables your data packet must travel through. For example, old copper-based infrastructure can significantly reduce data transfer speeds
- Additional physical distance to the destination
Obstacles that slow the flow of data to its destination increase latency (the time it takes for data to reach its destination), regardless of available bandwidth.
Using a VPN increases the distance your data travels because it has to reach the VPN server before it is forwarded to its intended destination. When you use our Secure Core feature, data is sent through two VPN servers (the first one is located in Switzerland, Iceland or Sweden), increasing latency.
VPN server download
While distance is the biggest factor in VPN performance, VPN server load is also important. Server load is simply how busy a particular VPN server is. That is, how many people use it.
The more people using a particular server, the more likely it is to overload the network of switches. A large number of users can also strain the server’s resources (processing power, memory, disk performance, etc.), which can affect overall speed.
As we discuss later in the article, our programs display a server load indicator that clearly shows the load on each server.
VPN protocols and the encryption used to protect their data require complex math that takes a computer’s CPU time to complete.
Even low-end mobile phones today (not to mention desktop computers) can handle the extra processing required to encrypt and decrypt data with VPN protection without significant performance degradation, but with VPN servers handling potentially hundreds of connections, the VPN protocol you currently using may affect your data.processing speed.
If implemented correctly, OpenVPN is very secure, but also a bit “clumsy” and slow compared to some other VPN protocols. This means that its implementation requires more processing power.
IKEv2 is widely considered very secure, but it is also a much more modern and powerful protocol than OpenVPN. Using IKEv2 therefore provides better speed than OpenVPN.
VPN booster is unique to Proton VPN and includes a set of technologies that can boost your VPN speed by over 400% in certain situations. Thanks to this new technology, you can always enjoy the best possible VPN speed when using our service. The core features of VPN accelerator are a redesigned OpenVPN that reduces server load by evenly distributing sessions across multiple CPU threads, a TCP delay-driven TCP flow control algorithm called BBR that significantly reduces latency, and many other improvements such as inter-process communication decoupling. . adapted to “partner processes” to improve delivery efficiency.
How to improve VPN speed performance
The Quick Connect feature automatically takes into account all the key factors when choosing the best server for you, but if you prefer manual control, you should consider the following factors.
In general, connecting to a server that is as geographically close as possible will give you the best speed. And as said before, this is the most important factor affecting VPN speed.
If you need to connect to a website or other online resource in a specific country, connect to the closest website that meets your needs. For example, if you live in Europe and want to watch the American version of Netflix, connecting to one of our servers in New York is a good option.
However, it should be noted that a VPN accelerator should mitigate performance loss due to distance anyway.
If possible, you should connect to a VPN server that is not busy. Proton VPN apps show the following server load for each of our servers, so you can manually select a fast server for your needs. The circle around the info button gives you a quick overview of the server.
This circle is green when the server load is low and turns yellow when the server load is moderate or red when the server is overloaded. Click the icon for more information.
Change the VPN protocol
IKEv2 is usually faster than OpenVPN, although if your IKEv2 connection is slow, you may want to see if switching to OpenVPN helps.
If you’re using OpenVPN, TCP mode can be effective for unblocking VPNs, but UDP mode is faster because TCP corrects errors while UDP doesn’t (see What’s the difference between UDP and TCP? for details).
Our Windows application supports OpenVPN in UDP and TCP modes. You can change the VPN protocol by going to Settings -> Connection tab -> Default protocol.
It is also possible to manually configure the built-in Windows VPN client to connect to Proton VPN servers using the IKEv2 protocol. For more information, see Proton VPN’s guide to Windows 10 IKEv2 VPN settings.
Mac operating system
Our MacOS application uses the IKEv2 protocol. You can connect to our servers using OpenVPN (UDP or TCP) by manually configuring the Tunnelblick open source client. See Set up OpenVPN on Mac with Tunnelblick for more information.
Our Linux CLI uses OpenVPN. Connecting in the usual way (“protonvpn-cli connect” or “protonvpn-cli c”) you can choose the protocol to use: OpenVPN UDP or OpenVPN TCP.
iOS and iPadOS
Our iOS app supports IKEv2 and OpenVPN (UDP and TCP) protocols. You can switch between protocols using the menu command Settings -> Security Settings -> Protocol.
Android (and Chromebook)
Our Android app also supports IKEv2 and OpenVPN (UDP and TCP) protocols. You can manually switch between protocols by going to Settings -> Smart Protocol and moving the switch to the off position.
You can now choose between IKEv2 and OpenVPN. If you choose OpenVPN, you can choose between TCP and UDP.
Do not use Secure Core or Tor
Our Secure Core and Tor VPN features can greatly improve privacy and security on your network, but you may want to disable them for the best speeds.
As described above, Secure Core routes your VPN connection through two VPN servers, increasing distance and congestion. There are also only three Secure Core server locations, which likely increases the distance that data must travel.
The Tor network routes your data through a random set of three nodes that can be located anywhere in the world, re-encrypting it each time. So Tor is slow at best.
Upgrade your VPN plan
Proton VPN offers a 100% free VPN plan with no data limits and access to servers worldwide (especially in the US, the Netherlands and Japan). We don’t set artificial speed limits, but our free servers tend to be slower than our Plus servers simply because more people use them. Which increases the server load.
It is also very likely that our free servers are not geographically very close to you, which increases the distance.