Subnet Calculator

Subnet Formula

Worked Example

192.168.10.77/26:

1. Mask = 26 ones then 6 zeros = 255.255.255.192
2. Network = address AND mask = 192.168.10.64; broadcast = network OR wildcard = 192.168.10.127
3. Hosts = 2^6 − 2 = 62

Wildcard mask: 0.0.0.63 · Broadcast address: 192.168.10.127 · First usable host: 192.168.10.65 · Last usable host: 192.168.10.126 · Usable hosts: 62 · Total addresses: 64 · Class (classful): C · Private address (RFC 1918): yes · Address in binary: 11000000.10101000.00001010.01001101 · Mask in binary: 11111111.11111111.11111111.11000000

GATE tip

For “which subnet does this host belong to” questions, only the octet where the mask is not 255 or 0 matters: 77 AND 192 = 64 gives the network 192.168.10.64.

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Frequently asked questions

Sources

Last reviewed: 2026-10-15. Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.