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Subnet Planning for Network Admins

Plan IP allocation, calculate usable hosts, and size subnets for your network.

로그인 불필요
/
/0/8/16/24/32
254
Usable hosts
256
Total addresses
Network address192.168.1.0/24
Usable host range192.168.1.1 – 192.168.1.254
Broadcast address192.168.1.255
Subnet mask255.255.255.0
Wildcard mask0.0.0.255
Mask (binary)11111111.11111111.11111111.00000000
IP classC
Address typePrivate (RFC 1918)

IPv4 subnetting reference. /31 and /32 are handled per RFC 3021 (point-to-point and single-host). All math runs locally in your browser.

Network Admin tips

🖧

Before deploying a VLAN, calculate the usable host count to make sure the subnet fits your device count plus growth headroom.

💡

Remember network + broadcast addresses are reserved — a /24 gives 254 usable hosts, not 256.

🎯

Use the binary mask view to teach or double-check VLSM (variable-length subnet masking) boundaries.

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