A Virtual Private Cloud (VPC) is a private network interface for collections of DigitalOcean resources. VPC networks are inaccessible from the public internet and other VPC networks, and traffic on them doesn’t count against bandwidth usage.
VPC is available at no additional cost.
Traffic between your resources inside of a VPC network does not count against your bandwidth billing transfer allowance. Traffic from one VPC network to another VPC network uses a public interface and does count against your bandwidth allowance.
VPC networks can vary in size from /28 up to /16. The default size is /20.