Tech
Subnet Calculator
A /24 subnet contains 256 total addresses and 254 usable hosts, because the network and broadcast addresses are reserved. This subnet calculator computes the mask, network, broadcast, and host range for any IPv4 address and CIDR prefix.
Quick answer
Network address identifies the subnet.
What this tells you
- •Network address identifies the subnet.
- •Broadcast address is the last address in the subnet.
- •Usable hosts exclude network and broadcast in standard subnets.
How to Use
- 1Enter an IPv4 address.
- 2Enter CIDR prefix (0-32).
- 3Calculate to view subnet mask and host range.
How It Works
Formula
Mask from CIDR, Network = IP AND Mask, Broadcast = Network OR inverse maskBitwise operations derive all subnet boundaries and host ranges.
Calculation note: values are processed in the order shown above, using the current input units.
Worked Examples
Typical /24 subnet
I P192.168.1.34
C I D R24
ResultNetwork 192.168.1.0, Broadcast 192.168.1.255, Hosts 254
Common mistakes
- Using invalid IPv4 formats
- Confusing CIDR and subnet mask notation
- Assuming /31 and /32 have normal host ranges
Frequently Asked Questions
CIDR is prefix-length notation indicating how many leading bits are network bits.
A /24 typically has 254 usable host addresses.
Yes, but standard usable-host logic differs for those edge cases.
The number after the slash counts how many leading bits of the address are network bits. A /24 means the first 24 bits identify the network, leaving 8 bits for hosts (256 addresses). Larger prefixes mean smaller subnets.
It estimates subnet calculator outputs using the visible inputs and formula assumptions on this page.