What subnet mask would you use for the 172.16.0.0 network, such that you can get 230 subnets and 170 hosts per subnet? - Quora
How to calculate a subnet mask from hosts and subnets | TechTarget
Subnet Mask Calculator
GitHub - ygvn/IPv6-Subnet-Calculator-Tool-JavaFX: IPv6 Subnet Calculator / Tool application lets you plan/subnet your assigned IPv6 address for all 128 bits.
FREE: SolarWinds Advanced Subnet Calculator – IP subnet calculation made easy – 4sysops
23. CCNA Ch12 - Create an IPv6 Subnet Calculator in Excel -Part1 - YouTube