IP Subnet Calculator
Calculate IP subnets online for free. Enter an IP address and CIDR notation to get network address, broadcast address, usable host range, subnet mask, and more.
Runs entirely in your browser — files never uploaded
Subnet Details
11000000.10101000.00000001.00000000
11111111.11111111.11111111.00000000
How to use IP Subnet Calculator
- 1. Enter an IP address. Type a valid IPv4 address like 192.168.1.0 into the input field.
- 2. Select the prefix length. Choose a CIDR prefix (/0 to /32) using the dropdown or enter a subnet mask directly.
- 3. View the results. See the full subnet breakdown including network address, broadcast address, host range, and binary representations.
FAQ
What is CIDR notation?
CIDR (Classless Inter-Domain Routing) notation combines an IP address with a prefix length (e.g., 192.168.1.0/24) to define a network. The prefix length indicates how many bits are used for the network portion.
What is the difference between total hosts and usable hosts?
Total hosts is 2^(32 - prefix). Usable hosts subtracts 2 from that total because the first address is the network address and the last is the broadcast address. For /31 and /32, special rules apply.
What are private IP ranges?
Private IP addresses are reserved for internal networks: 10.0.0.0/8 (Class A), 172.16.0.0/12 (Class B), and 192.168.0.0/16 (Class C). They are not routable on the public internet.
Is my IP address sent to a server?
No. All subnet calculations are performed entirely in your browser using JavaScript bitwise operations. Nothing is transmitted.
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