A VPN adds an encrypted tunnel between your device and an Internet-connected router somewhere else in the world, from which your requests are routed to their intended destination. In other words the absolute best you can hope for is that it doesn't add significant amounts of latency to your requests. This is a physical limitation based on the capacity of the VPN provider, and on the speed of light.
When it comes to bandwidth, your device or the VPN endpoint will be the bottleneck. If you're on a slow connection, the VPN won't be able to tunnel data faster than your connection can handle. If the VPN service is overcommitted, you may get even slower throughput than your own connection could provide.
A VPN service provides a number of benefits:
- A way for your computer to appear to exist in another location
- A way to make it harder to track you individually (as long as you don't use your VPN to log on to known accounts on mail servers, social media, etc)
- A somewhat safer way to surf and work using public WiFi (your data passes through an encrypted tunnel to a known egress point which you may trust more than your local StarBucks)
- The ability to work on a remote network as if your device was directly connected to it
Speed is not a benefit of VPN services.
There are two exceptions to the rule that I can think of immediately:
- If your ISP intentionally limits transfer speeds of certain content and you're able to circumvent this limitation by hiding the content within a VPN, you may be able to reach the full capacity of your Internet connection for such content in certain circumstances.
- If you have a cheap router and do something that saturates its capacity for external connections, connecting to a VPN service from a more powerful computer within your network will tunnel all of these these connections through the router within a single enclosing connection, and this may alleviate the problem.
depends on the country u connect to. and server...
we think of an ISP, the closer the DNS server, the better, but VPN is just a server (or servers) elsewhere... it can slow down connection. as there is also overheard related to encrypting the connection. Remember u are using your VPN's DNS server when u run a DNSleak test, not your ISP's, & therefore be a 'leak'