AdeOS interactive tools

Cisco Wildcard Mask Calculator

Convert a familiar subnet mask into the inverse wildcard format used by Cisco-style policies.

Wildcard Mask Calculator

Cisco ACL Helper
Cisco ACL Format
Quick Reference Table
About Wildcard Masks:

Wildcard masks are used in Cisco ACLs to match IP address ranges. A 0 bit means "must match" and a 1 bit means "don't care". The wildcard mask is the bitwise inverse of the subnet mask.

Generate a wildcard mask and explain the network range it matches.

Inputs

Enter an IPv4 address with CIDR prefix or subnet mask.

Outputs

Subnet mask, wildcard mask, and matching network details.

Example

Build an ACL match for 10.10.0.0/16.

Important note

Results support planning and learning; verify production changes against your platform and change controls.

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