IP Range & Subnet Calculator
/32 (255.255.255.255)
/31 (255.255.255.254)
/30 (255.255.255.252)
/29 (255.255.255.248)
/28 (255.255.255.240)
/27 (255.255.255.224)
/26 (255.255.255.192)
/25 (255.255.255.128)
/24 (255.255.255.0)
/23 (255.255.254.0)
/22 (255.255.252.0)
/21 (255.255.248.0)
/20 (255.255.240.0)
/19 (255.255.224.0)
/18 (255.255.192.0)
/17 (255.255.128.0)
/16 (255.255.0.0)
/15 (255.254.0.0)
/14 (255.252.0.0)
/13 (255.248.0.0)
/12 (255.240.0.0)
/11 (255.224.0.0)
/10 (255.192.0.0)
/9 (255.128.0.0)
/8 (255.0.0.0)
/0 (0.0.0.0)
Please enter a valid IPv4 address (e.g., 192.168.1.1).
Network Address:
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Usable Host Range:
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Broadcast Address:
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Total Number of Hosts:
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Usable Number of Hosts:
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Subnet Mask:
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Wildcard Mask:
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What is an IP Range?
An IP range represents the span of IP addresses accessible within a specific network segment or subnet. It is defined by the Network Address (the starting point) and the Broadcast Address (the ending point). Understanding these ranges is crucial for network configuration, security firewall rules, and avoiding address conflicts.
How the Calculation Works
IP range calculation relies on binary logic. Here is the step-by-step process:
- IP to Binary: The IPv4 address is converted into a 32-bit binary number.
- The Subnet Mask: The CIDR prefix (e.g., /24) determines how many bits are reserved for the network portion. A /24 mask means the first 24 bits are 1s and the remaining 8 bits are 0s.
- Network Address: Calculated by performing a bitwise AND operation between the IP address and the subnet mask.
- Broadcast Address: Calculated by taking the network address and setting all the host bits to 1.
- Usable Hosts: These are the addresses between the network and broadcast addresses. Formula:
2^(32 - prefix) - 2.
Real-World Example
If you have an IP of 192.168.1.10 with a /24 prefix:
- Subnet Mask: 255.255.255.0
- Network Address: 192.168.1.0
- First Usable: 192.168.1.1
- Last Usable: 192.168.1.254
- Broadcast: 192.168.1.255
- Total Hosts: 254 usable devices.
Why CIDR Matters
Classless Inter-Domain Routing (CIDR) replaced the old Class A, B, and C system. It allows for much more flexible allocation of IP addresses, which helps conserve the limited supply of IPv4 addresses. Using a calculator like this ensures that network engineers don't make manual errors that could lead to overlapping networks or routing loops.