CIDR Calculator
https://subnetcalculator.info/CidrCalculatorCIDR is a replacement for the old process of assigning Class A, B and C addresses with a generalized network "prefix". Instead of being limited to network identifiers (or "prefixes") of 8, 16 or 24 bits, CIDR currently uses prefixes anywhere from 0 to 32 bits (currently in use 13 to 27 bits).
Subnet Calculator - IP and CIDR - NetworkCalc
https://networkcalc.com/subnet-calculatorOnline Subnet Calculator and Free API. The online subnet calculator allows you to quickly calculate the network details for an IPv4 address or CIDR block . Use this free online calculator to determine subnet mask, wildcard mask, network address, broadcast address, and assignable hosts. Use this tool as a subnet mask calculator to translate ...