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Wildcard Mask Calculator
Enter a CIDR prefix to calculate its subnet mask and wildcard mask, used in Cisco ACLs and OSPF configuration.
How to use this tool
- 1Set the CIDR prefix.
- 2See the subnet mask and its wildcard (inverse) mask.
Frequently asked questions
What is a wildcard mask used for?+
Wildcard masks are the inverse of subnet masks, used in Cisco access control lists (ACLs) and OSPF network statements to match address ranges.
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