IPv4 subnet / CIDR calculator
Calculate an IPv4 / CIDR subnet: mask, range, broadcast and host count.
Réseau / Network
192.168.1.0Masque / Mask
255.255.255.0CIDR
/24Wildcard
0.0.0.255Broadcast
192.168.1.255Premier hôte / First host
192.168.1.1Dernier hôte / Last host
192.168.1.254Hôtes utilisables / Usable hosts
254Total adresses
256🔒 100% client-side — no data sent
Enter an IPv4 address and a CIDR prefix to get the mask, network address, host range, broadcast and number of available hosts. A fast tool for planning or checking a network split. Calculations run locally in your browser, with no data sent anywhere.
What is it for?
- ▸ Find the usable host range of a network
- ▸ Convert a CIDR prefix to a subnet mask
- ▸ Check the broadcast address before a config
- ▸ Estimate the number of hosts in a subnet
FAQ
What is the difference between /24 and 255.255.255.0?
None: /24 is the CIDR notation for the mask 255.255.255.0. Both describe the same network split.
Does the host count include the network and broadcast?
The usable host count excludes the network and broadcast addresses.
Is IPv6 supported?
This tool is dedicated to IPv4 and IPv4 CIDR.
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