IPv4 CIDR Subnet Calculator
IPv4 CIDR Subnet Calculator
Show network, mask, address range and conventional host capacity.
CIDR notation describes a network prefix and address range without discovering devices.
Enter the IPv4 address and prefix, then compare mask, network and host figures.
How to use IPv4 CIDR Subnet Calculator
- Enter IPv4 address and CIDR prefix.
- Select Process input. Read the returned values alongside the assumptions below before copying, exporting or acting on the result.
Why choose this tool?
The range view helps explain how addresses fit within the same subnet.
Before you use the result
For /31, both addresses are shown as point to point endpoints under RFC 3021. A /32 is one host route. No reachability scan or IP lookup is performed.
Questions about IPv4 CIDR Subnet Calculator
How are /31 and /32 handled?
A /31 shows point to point endpoints. A /32 represents one host route rather than a conventional shared subnet.
What should I check before using IPv4 CIDR Subnet Calculator?
Check IPv4 address and CIDR prefix. Use the exact units shown beside the controls and replace any example values with your own inputs.
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