IPv4 Subnet Trainer

Given an IPv4 address and prefix length (CIDR), determine its network/subnet, broadcast, and first/last usable addresses, plus the subnet mask.

1st Octet 2nd Octet 3rd Octet 4th Octet

Find the Subnet Information

— /— (— possible hosts)

Subnet mask

Network/Subnet address

Broadcast address

First usable

Last usable

Stats & Controls

Score

Streak

Best

Timer: 00:00

Rounds: 0

Difficulty

Skip /31 and /32 Require Net/Bcast first

How scoring works

5 checks: mask, network, broadcast, first, last.
+1 point per correct (max +5/round).
Streak +1 only if all five are correct on the first try.