Network Address Calculator
Calculate the network address from any IP address and CIDR prefix.
About This Calculator
Calculate the network address from any IP address and CIDR prefix. Use the calculator above for instant results.
Worked Examples
- Network: 192.168.5.0 | First host: 192.168.5.1
Answer: 192.168.5.0
- Network: 10.0.0.0 | First host: 10.0.0.1
Answer: 10.0.0.0
- Network: 172.16.48.0 | First host: 172.16.48.1
Answer: 172.16.48.0
Who Uses This Calculator?
Find network address for subnetting.
Routing and subnet planning.
Subnetting practice.
Networking exam prep.
Common Mistakes to Avoid
❌ Network address = IP AND mask
Bitwise AND of IP and subnet mask = network address. Host bits all become 0.
❌ Not assignable to hosts
Network address identifies the subnet in routing. Cannot be assigned to a device.
Frequently Asked Questions
Formula?
Network = IP AND subnet mask. 192.168.5.50 AND 255.255.255.0 = 192.168.5.0.
Why does it matter?
Routers use network addresses in routing tables. Every route in a routing table is a network address with prefix.
Default gateway?
The router interface on your subnet. Packets to external destinations go to default gateway for routing.