ISPbox

Free IPv4 Subnet Calculator

CIDR to Subnet Mask converter. Calculate network ranges and wildcards.

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Calculation Results

Network Address
192.168.1.0
Broadcast Address
192.168.1.255
Subnet Mask
255.255.255.0
Wildcard Mask
0.0.0.255
Usable Host Range
192.168.1.1 - 192.168.1.254

Network Properties

Usable Hosts
254
Total Ips
256
CIDR Notation
/24
IP Class
C
IP Type
Private
IP Addr: 11000000 10101000 00000001 00000001
Subnet : 11111111 11111111 11111111 11111111 11111111 11111111 11111111 00000000

How to calculate Subnet Mask from CIDR?

Classless Inter-Domain Routing (CIDR) is a method for allocating IP addresses and IP routing. The CIDR notation specifies the number of bits in the network prefix (the "slash" notation, e.g., /24).

This utility calculates the Subnet Mask, Network Address, Broadcast Address, and the range of usable host IP addresses. It also provides the Wildcard Mask, which is useful for configuring ACLs (Access Control Lists) on routers like Cisco or Mikrotik.

Common Subnets

  • /24 (255.255.255.0) - 254 Usable Hosts (Standard LAN)
  • /30 (255.255.255.252) - 2 Usable Hosts (PtP Links)
  • /32 (255.255.255.255) - 1 Usable Host (Loopback / Single IP)