CIDR Calculator
Calculate IPv4 network, broadcast, host range, and netmask from a CIDR block. Free subnet calculator in your browser.
Network
192.168.1.0
Broadcast
192.168.1.255
First host
192.168.1.1
Last host
192.168.1.254
Netmask
255.255.255.0
Wildcard
0.0.0.255
Total addresses
256
Usable hosts
254
Network and broadcast addresses are reserved.
More
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Frequently asked questions
What is CIDR Calculator?+
Enter an IPv4 CIDR such as 192.168.1.0/24 and see the network, broadcast, first and last host, netmask, wildcard, and usable host count.
How do I use CIDR Calculator?+
Handles /31 point-to-point links and /32 single hosts. Copy any address or count. Calculated locally — nothing is sent to a server
Is CIDR Calculator free?+
Yes, CIDR Calculator is completely free. No account or sign-up required, and all processing happens in your browser — nothing is sent to a server.
Is my data safe when I use CIDR Calculator?+
Yes. CIDR Calculator runs entirely in your browser using JavaScript and Web APIs — your input is never uploaded, transmitted, or stored on any server.