What is CIDR notation?

CIDR (Classless Inter-Domain Routing) notation represents a subnet mask using a slash followed by the number of leading 1-bits (e.g., /24 equals 255.255.255.0).

Why are two IP addresses subtracted from total hosts?

In IPv4 networking, the first IP address is reserved for Network ID and the last IP address is reserved for Broadcast.

Developer & Network Utility

IPv4 Subnet Calculator

Calculate network address, subnet mask, broadcast IP, usable host range, and binary representations for CIDR notation.

Network Parameters

IP Address

Subnet Mask / CIDR Prefix (/24)

/24

Network & Broadcast Address

192.168.1.0 / 24

Subnet Mask: 255.255.255.0

Usable Host Range:192.168.1.1 - 192.168.1.254

Broadcast Address:192.168.1.255

Total Usable Hosts:254

IP (Bin): 11000000.10101000.00000001.00000001

Mask (Bin): 11111111.11111111.11111111.00000000

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