The VPN technology will decrease your actual speed as ClearVPN applies encryption to your data and routes it through a server that may be on the other side of the planet. So, your VPN speed will depend on your location, the server (how far away it is), and the used protocol.
If you activate the Optimal location preset or a country with the lowest ping in our Country list, ClearVPN will connect you to the closest server. This way, your speed will be less affected by the distance, and you shall expect no more than a 15-25% drop in speed.
If you connect to the farthest server in the Country list, your speed may drop by 25-70%.