Subnet Calculator

Calculate IP subnet details instantly. Enter an IP address and CIDR prefix to get network address, broadcast, usable host range, subnet mask, and more. Pure client-side.

Quick Examples

Network Address —
Broadcast Address —
Usable Host Range —
Usable Hosts —
Total Hosts —
Subnet Mask —
Wildcard Mask —
Subnet Class —
Binary
IP—
Mask—

About Subnet Calculator

Calculate IPv4 subnet details instantly. Enter any IP address with a CIDR prefix (e.g., 192.168.1.0/24) and get the network address, broadcast address, usable IP range, subnet mask, wildcard mask, and subnet class. All calculations run locally in your browser.

Features

  • Instant subnet calculation from any IPv4 + CIDR input
  • Network address, broadcast, and usable host range
  • Subnet mask, wildcard mask, and binary representation
  • Subnet class detection (A, B, C, D, E)
  • Quick examples for common network sizes
  • Copy any result or all results to clipboard

FAQ

What is CIDR notation?
CIDR (Classless Inter-Domain Routing) notation combines an IP address with a prefix length, like 192.168.1.0/24. The /24 means the first 24 bits are the network portion, equivalent to subnet mask 255.255.255.0.
What is the broadcast address?
The broadcast address is the last address in a subnet, used to send data to all hosts on that network. For example, in 192.168.1.0/24, the broadcast is 192.168.1.255.
How many usable hosts are in a /24 subnet?
A /24 subnet has 256 total addresses. After reserving the network address (.0) and broadcast address (.255), there are 254 usable host addresses.
Is this calculator free?
Yes, completely free. All calculations happen in your browser with no server calls.