Subnet calculator
Enter an IPv4 CIDR to get its network/broadcast address, usable host range, subnet and wildcard mask, and address counts. Computed entirely in your browser — no lookup. IPv6 support is a future enhancement.
Network address10.0.0.0
Broadcast address10.0.0.255
Subnet mask255.255.255.0
Wildcard mask0.0.0.255
Usable host range10.0.0.1 – 10.0.0.254
Total addresses256
Usable hosts254
Prefix length/24
Split into smaller subnets
Divide the CIDR above into consecutive subnets of a longer (more specific) prefix length — e.g. split a /24 into four /26s.