CIDR Subnet Calculator - SimeonOnSecurity
NOTE: This tool runs entirely in your browser with client-side JavaScript. The IP address you enter is never transmitted, logged, or stored. All subnet arithmetic happens locally on this page.
Results
| Enter an address and press Calculate. |
Binary Breakdown
Enter an address to see the binary view.
How the Math Works
- Network address is the input address with every host bit cleared, found by ANDing with the netmask.
- Broadcast address is the network address with every host bit set, found by ORing with the wildcard mask.
- Usable hosts excludes the network and broadcast addresses, except on /31 and /32 where that rule does not apply.
- Total addresses is 2 raised to the power of the host bit count, which is 32 minus the prefix length.
Sponsored by The Cyber Sentinels Club
