This tool returns a variety of information regarding IPv4 subnets, including possible network addresses, usable host ranges, subnet mask, and IP class.
What is a subnet?
A subnet (short for subnetwork) is a smaller network inside a larger IP network. It divides a large network into smaller, more manageable parts to improve performance, security, and traffic flow. Subnets help organize devices and control access between different network sections.
How does subnetting work?
Subnetting works by borrowing bits from the IP address's host portion to create multiple smaller networks, called subnets. Each subnet has its own range of IP addresses and a subnet mask that defines its size. This allows network administrators to efficiently assign IP addresses and isolate traffic between subnets for better control and scalability.
What is a subnet mask?
A subnet mask is a number that separates the network part of an IP address from the host part. It looks similar to an IP address (e.g., 255.255.255.0) and helps routers and devices know which part of the address identifies the network and which part identifies individual devices (hosts) within that network.
How do I calculate the number of hosts?
To calculate the number of usable hosts in a subnet, use the formula:
2^(number of host bits) - 2
The -2 accounts for the network and broadcast addresses.
For example, a /24 subnet has 8 bits for hosts → 2^8 - 2 = 254 usable IP addresses.
What's the difference between IPv4 and IPv6 subnetting?
The main difference between IPv4 and IPv6 subnetting is the address size and format.
IPv4 uses 32-bit addresses, allowing around 4.3 billion unique IPs. Subnetting in IPv4 often focuses on conserving IP space.
IPv6 uses 128-bit addresses, offering a massive number of IPs. Subnetting in IPv6 is simpler, often using a fixed /64 for most networks. It emphasizes efficient routing and network segmentation rather than IP conservation.