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Subnet Calculator | IPv4 Subnet & Mask Calculator

01/ 06

Free IPv4 subnet calculator for network address, subnet mask, broadcast address and usable host range from an IP and CIDR prefix.

Calculator inputs

IPv4

You can also enter an address as 192.168.1.10/24.

/24
/0/8/16/24/32
Try
Enter ↵

Calculation results

NETWORK ADDRESS
192.168.1.0/24
254usable addresses
Subnet mask
255.255.255.0
Broadcast
192.168.1.255
First host
192.168.1.1
Last host
192.168.1.254
Wildcard mask
0.0.0.255
Total addresses
256

32-bit address structure

Network 24 Host 8
11000000
192
10101000
168
00000001
1
00001010
10

Mathematical range excluding network and broadcast. Verify assignability for special-purpose address space.

HOW IT WORKS

Understand your subnet and host range

An IPv4 address contains 32 bits. In a /24, the first 24 identify the network and the remaining 8 identify hosts. The block contains 2^(32−24), or 256 addresses.

For a conventional /0 to /30 subnet, the network and broadcast addresses are excluded. For 192.168.1.10/24, the host range is 192.168.1.1–192.168.1.254. A /31 is treated as a point-to-point link and a /32 as one address.

Results describe the mathematical address block. They do not establish assignability or routing for reserved, multicast, loopback or other special-purpose addresses.

FAQ

Frequently asked questions

What subnet mask is /24?

It is 255.255.255.0. Of its 256 addresses, 254 are usable as hosts in a conventional LAN.

Are /31 and /32 supported?

Yes. A /31 uses both addresses on an RFC 3021 point-to-point link. A /32 represents a single address. Neither shows a directed broadcast.

Are entered IP addresses sent to a server?

No. Calculation inputs and results are processed in the browser and are not sent to a calculation service or analytics event.