Easily analyze IPv4 and IPv6 subnet configurations with our powerful IP Subnet Calculator. Instantly generate subnet details such as available network addresses, valid host ranges, subnet masks, IP classes, and more. Ideal for network planning, system administration, and IT professionals.
IPv4 Subnet Calculator
IPv6 Subnet Calculator
P Subnet Calculator – IPv4 & IPv6 Subnetting Tool
Optimize your network design and IP planning using our advanced IP Subnet Calculator. This tool supports both IPv4 and IPv6 and helps you instantly generate key details like subnet masks, CIDR notations, IP classes, network addresses, and usable host ranges.
What Is Subnetting?
Subnetting is the process of splitting a larger IP network into smaller, efficient segments known as subnets. It allows better control over traffic flow, improves security, and ensures efficient use of IP address space.
Today, IPv4 (Internet Protocol version 4) is still the most common, but IPv6 adoption is increasing due to its vast address capacity and improved structure.
IP Address Breakdown
An IP address includes:
- Network Prefix – Identifies the network segment
- Host Identifier – Identifies a specific device on that network
This division is made clearer using CIDR notation (e.g., /24), which specifies how many bits belong to the network portion. In IPv4, subnet masks like 255.255.255.0 are commonly used. In IPv6, the prefix length serves the same purpose, without traditional subnet masks.
Subnet Classes
Before CIDR, IP addresses were categorized as:
- Class A: Large networks
- Class B: Medium networks
- Class C: Smaller networks
CIDR replaced classful networking by allowing variable-length subnet masks, giving admins more flexibility in how networks are divided.
IPv4 Subnet Table
Here’s a complete table of prefix sizes, subnet masks, and the number of usable hosts per subnet:
| Prefix size | Network mask | Usable hosts per subnet |
|---|---|---|
| /1 | 128.0.0.0 | 2,147,483,646 |
| /2 | 192.0.0.0 | 1,073,741,822 |
| /3 | 224.0.0.0 | 536,870,910 |
| /4 | 240.0.0.0 | 268,435,454 |
| /5 | 248.0.0.0 | 134,217,726 |
| /6 | 252.0.0.0 | 67,108,862 |
| /7 | 254.0.0.0 | 33,554,430 |
| Class A | ||
| /8 | 255.0.0.0 | 16,777,214 |
| /9 | 255.128.0.0 | 8,388,606 |
| /10 | 255.192.0.0 | 4,194,302 |
| /11 | 255.224.0.0 | 2,097,150 |
| /12 | 255.240.0.0 | 1,048,574 |
| /13 | 255.248.0.0 | 524,286 |
| /14 | 255.252.0.0 | 262,142 |
| /15 | 255.254.0.0 | 131,070 |
| Class B | ||
| /16 | 255.255.0.0 | 65,534 |
| /17 | 255.255.128.0 | 32,766 |
| /18 | 255.255.192.0 | 16,382 |
| /19 | 255.255.224.0 | 8,190 |
| /20 | 255.255.240.0 | 4,094 |
| /21 | 255.255.248.0 | 2,046 |
| /22 | 255.255.252.0 | 1,022 |
| /23 | 255.255.254.0 | 510 |
| Class C | ||
| /24 | 255.255.255.0 | 254 |
| /25 | 255.255.255.128 | 126 |
| /26 | 255.255.255.192 | 62 |
| /27 | 255.255.255.224 | 30 |
| /28 | 255.255.255.240 | 14 |
| /29 | 255.255.255.248 | 6 |
| /30 | 255.255.255.252 | 2 |
| /31 | 255.255.255.254 | 0 |
| /32 | 255.255.255.255 | 0 |
Why Use Our IP Subnet Calculator?
- Calculate available host ranges with ease
- Get full subnet info including broadcast and network address
- Supports both IPv4 and IPv6 calculations
- Ideal for IT professionals, network engineers, and students
How It Works
Simply enter an IP address and subnet prefix (e.g., 192.168.0.1/24). Our tool will instantly show:
- Subnet mask
- Network address
- Broadcast address
- Range of usable IPs
- Number of hosts
- IP class and CIDR info
Start using the IP Subnet Calculator now to streamline your IP planning and network management tasks. It’s fast, free, and accurate.