Wildcard Mask Calculator
Calculate the IPv4 wildcard mask from a CIDR prefix or valid contiguous subnet mask.
Processed locally — your input stays in this browser.
Examples and edge notes
Examples: /24 → 0.0.0.255, /30 → 0.0.0.3, /32 → 0.0.0.0. A wildcard is the 32-bit inverse of a subnet mask.
About Wildcard Mask Calculator
Convert between an IPv4 subnet mask and its inverse wildcard mask.
How to use it
Enter the requested value, review it for accuracy, then run the tool. Read the labeled result fields before copying or using them in another workflow.
Understanding the result
The result presents the values returned or calculated for this specific request. Labels and status messages distinguish successful data, empty results, validation problems, and network errors.
Limitations and privacy
Results are calculated from the values you provide and should be verified against your network requirements before operational changes. Runs locally in your browser; the value you enter is not sent to the Network Tools API.