IPv4 Subnet Calculator
Find the network, broadcast, host range, netmask and address count for an IPv4 CIDR block.
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What is IPv4 Subnet Calculator?
IPv4 Subnet Calculator derives network boundaries, host range and mask information from an address and CIDR prefix.
How to use IPv4 Subnet Calculator
- 01
Enter an IPv4 address and a prefix from 0 to 32.
- 02
Change the prefix to compare network sizes and host capacity.
- 03
Use the network, broadcast, first host, last host and address totals in your plan.
IPv4 Subnet Calculator FAQ
Does the entered address need to be the network address?
No. Enter any address inside the subnet; the calculator derives the containing network boundary.
Is IPv4 Subnet Calculator private to use?
Yes. Address and network calculations use only the values entered in your browser and do not probe external systems.