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Convert subnet masks into wildcard masks for ACL rules.
Wildcard Mask Calculator converts an IPv4 subnet mask into the wildcard mask commonly used in ACL and routing-policy syntax. Use it when documenting or preparing network rules that require inverted mask notation.
Enter the address, prefix, port, packet, or capacity values exactly as labelled, then compare the derived values with the real network plan.
Wildcard mask: 0.0.0.255
Mask bits: 11111111.11111111.11111111.00000000
Wildcard bits: 00000000.00000000.00000000.11111111
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