CIDR / Subnet Calculator
Enter any IPv4 address in CIDR notation to instantly calculate the network address, broadcast, usable range, subnet mask, wildcard mask, and binary breakdown.
Input
Network Details
Binary Breakdown
| Field | Dotted Decimal | Binary |
|---|
Nearby Prefixes
| Prefix | Subnet Mask | Wildcard | Hosts/Net | Subnets from /8 |
|---|
What is CIDR notation?
CIDR notation expresses an IP address and routing prefix as a single string, e.g. 192.168.1.0/24. The number after the slash is the prefix length — count of leading 1-bits in the subnet mask.
Wildcard mask
The wildcard mask is the bitwise inverse of the subnet mask. Used in Cisco ACLs, OSPF, and firewall rules. For a /24, the wildcard is 0.0.0.255.