IP Subnet Calculator (CIDR)
Network, broadcast, mask and host range of an IPv4 subnet.
Input
This tool runs entirely in your browser. The data you paste or load is never uploaded.
Result
Enter your input, then run the tool.
About this tool
Calculates the network address, broadcast address, subnet mask, wildcard mask, first and last usable host and number of hosts for an IPv4 address in CIDR notation, and says whether the range is private, loopback or public.
How to use it
- Enter an address with its prefix, such as 192.168.1.10/24, or an address and a mask.
- Press Calculate.
- Read the network range and masks.
Frequently asked questions
How many hosts does a /24 hold?
256 addresses, of which 254 are usable hosts: the first is the network address and the last is the broadcast address.
What about /31 and /32?
A /32 is a single host and a /31 is a point-to-point link with two usable addresses (RFC 3021); the tool reports both correctly.
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