IP Subnet Calculator
Calculate network address, broadcast address, and host ranges for IPv4 subnets. Essential tool for network engineers and IT professionals.
About IP Subnetting
Subnetting is the practice of dividing a network into two or more smaller networks. It helps in improving network performance and security.
CIDR Notation
CIDR (Classless Inter-Domain Routing) notation is a compact representation of an IP address and its associated routing prefix. It is written as an IP address, a slash, and a number between 0 and 32 (e.g., 192.168.1.0/24). The number represents the count of leading 1-bits in the subnet mask.
Key Terms
- Network Address: The first address in the subnet. It identifies the subnet itself.
- Broadcast Address: The last address in the subnet. Used to send data to all hosts on the subnet.
- Host Range: The IP addresses available for devices (Network Address + 1 to Broadcast Address - 1).
Private IP Ranges (RFC 1918)
- Class A: 10.0.0.0 to 10.255.255.255
- Class B: 172.16.0.0 to 172.31.255.255
- Class C: 192.168.0.0 to 192.168.255.255
? Frequently Asked Questions
A subnet mask is a 32-bit number that masks an IP address and divides the IP address into network address and host address.
Two addresses in every subnet are reserved: the very first address is the Network Address, and the very last one is the Broadcast Address. They cannot be assigned to individual devices.
A /24 network means the first 24 bits are the network part (Subnet Mask 255.255.255.0). It allows for 256 total IP addresses, with 254 usable hosts.
Yes. A /32 represents a single IP address (host route). A /31 is often used for point-to-point links between routers, containing exactly 2 addresses (standard logic often shows 0 usable hosts due to lack of distinct network/broadcast, but modern routers support using both IPs).