Subnet Calculator – IP Address & CIDR Calculator
Calculate subnet mask, network address, broadcast address, and host range from an IP address and CIDR prefix length. Free science calculator, no signup.
איך להשתמש במחשבון זה
- הזן IP Address
- הזן CIDR Prefix (0-32)
- לחץ על כפתור חשב
- קרא את התוצאה המוצגת מתחת למחשבון
שאלות נפוצות
What is the difference between a subnet mask and CIDR notation?
They express the same information in different formats. 255.255.255.0 (subnet mask) = /24 (CIDR). Count the consecutive 1s in the binary subnet mask to get the CIDR prefix. CIDR is more compact and is standard in modern networking.
How many hosts can a /24 subnet support?
A /24 subnet has 8 host bits, providing 2⁸ = 256 total addresses. Subtract 2 (network address and broadcast address) = 254 usable host addresses. This is the most common subnet size for small to medium networks.
What is the purpose of a broadcast address?
A broadcast address (all host bits = 1) allows a device to send a packet to every host on the subnet simultaneously. For 192.168.1.0/24, the broadcast is 192.168.1.255. No device should be assigned this address as a static IP.
What is the difference between IPv4 and IPv6?
IPv4 uses 32-bit addresses (about 4.3 billion total). IPv6 uses 128-bit addresses, providing 340 undecillion addresses — enough for every grain of sand on Earth to have billions of addresses. IPv6 is written in hexadecimal (e.g., 2001:0db8:85a3::8a2e:0370:7334). IPv6 adoption continues to grow as IPv4 addresses are exhausted.
Why does my router show 192.168.1.1 as its address?
192.168.1.1 is the default gateway — the first usable host address in the common 192.168.1.0/24 home network range. It's chosen by convention; your router could use any address in 192.168.1.1–192.168.1.254. The router connects your private 192.168.x.x network to the public internet using NAT (Network Address Translation).
עודכן לאחרונה: March 2026