Network Address
192.168.10.0
Subnet Calculator
Enter an IP address and prefix length to calculate subnet information.
Subnet Calculator
Enter an IP address and prefix length to calculate subnet information.
Usable Hosts
192.168.10.1 - 192.168.10.254
Broadcast Address
192.168.10.255
Subnet Mask
255.255.255.0
Subnet Visualization
CIDR:/24
Mask:255.255.255.0
Block Size:256
Total Addresses:256
192
Network
168
Network
10
Network
0
Host
0
Network
1 - 254
Usable Host Range
255
Broadcast
Subnet Details
| Prefix Length | /24 | Total Addresses | 256 |
| Subnet Mask (Decimal) | 255.255.255.0 | Usable Hosts | 254 |
| Subnet Mask (Binary) | 11111111.11111111.11111111.00000000 | ||
| Wildcard Mask | 0.0.0.255 | Host Bits | 8 |
How to use the subnet calculator
- Enter an IPv4 address followed by a CIDR prefix, for example 192.168.10.0/24.
- Click Calculate. The tool returns network, broadcast, usable host range and mask.
- Use the visualisation strip to see octet-by-octet how the prefix splits network bits from host bits.
Frequently asked questions
How do I calculate a /27 subnet by hand?
A /27 has 5 host bits, so 2^5 = 32 addresses per block. Subtract 2 for the network and broadcast and you get 30 usable hosts. The block boundary in the fourth octet steps by 32: .0, .32, .64, .96 and so on.
What is the difference between network address and broadcast address?
The network address has all host bits set to 0 and identifies the subnet itself. The broadcast has all host bits set to 1 and reaches every host on that subnet. Neither can be assigned to a host interface.
Why are 2 addresses subtracted from the total host count?
Classic IPv4 reserves the all-zeros host portion as the network address and the all-ones host portion as the directed broadcast. RFC 3021 makes an exception for /31 point-to-point links, where both addresses are usable.
How is a /31 subnet used in point-to-point links?
RFC 3021 allows /31 prefixes (two addresses) on point-to-point links, treating both as usable host addresses. This eliminates the historical waste of /30s on router-to-router links.