IP Subnet Calculator: Understanding Subnetting and CIDR Notation
Published: 2026-04-27 · 7 min read
Subnetting is a fundamental networking skill. Learn how to divide networks, calculate subnet masks, and understand CIDR notation.
IP Subnetting Explained
Subnetting divides a large network into smaller, more manageable sub-networks. It improves security, reduces broadcast traffic, and makes IP address management easier.
IPv4 Address Structure
An IPv4 address is 32 bits, written as four octets: 192.168.1.100
| Octet | Binary | Decimal |
|-------|--------|---------|
| 1st | 11000000 | 192 |
| 2nd | 10101000 | 168 |
| 3rd | 00000001 | 1 |
| 4th | 01100100 | 100 |
Common Subnet Masks
| CIDR | Subnet Mask | Usable Host...
Try the free tool: IP Subnet Calculator
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