CIDR to IP Range

Summary

Enter a CIDR block and instantly see the network address, broadcast, subnet mask, IP range, and usable host count.

How it works

1. Enter a CIDR block in the format x.x.x.x/prefix (e.g. 192.168.1.0/24).
2. The tool parses the prefix length to derive the subnet mask.
3. It calculates the network address by applying the mask to the host address.
4. The broadcast address is computed as network address OR (NOT mask).
5. First and last usable hosts are network + 1 and broadcast - 1 respectively.
6. Results update instantly as you type.

Use cases

• Plan IP address allocation for cloud VPCs and subnets.
• Verify firewall rules that reference CIDR ranges.
• Debug routing table entries that use CIDR notation.
• Quickly determine how many hosts fit inside a given subnet.
• Convert between CIDR prefix lengths and dotted-decimal subnet masks.
• Check whether two CIDR blocks overlap before merging networks.

Frequently Asked Questions