CIDR calculator
Calculate the IP range, netmask, broadcast and host count of any IPv4 CIDR block like 10.0.0.0/16. Free.
In your browser
Also with the subnet calculator
About this tool
Enter a CIDR block such as 192.168.1.0/24 to see the first and last usable address, the netmask, the broadcast address and how many hosts it holds.
How to use it
- 1 Enter an address in CIDR form, like 10.0.0.0/16.
- 2 Read the network details.
Questions
Is my data uploaded?
No. This tool runs in your browser, so your text and files never reach our server.
Is this tool free?
Yes. It’s free to use with no sign-up and no limits for normal use.
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