Subnetting Practice for IT Students

Check your subnetting homework and CCNA practice problems instantly.

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IPv4 address

Prefix

/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.

IT Students tips

🎓

Studying for CCNA / Network+? Work the problem by hand, then verify network, broadcast, and host range here.

💡

The binary mask and wildcard mask help connect the dot-decimal notation to what's happening bit-by-bit.

🎯

Practice the /25, /26, /27, /28 boundaries — these are the most common exam questions.

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