IP and CIDR calculator
Calculate address ranges, subnets and CIDR relationships for network rules. Results describe address mathematics, not reachability or allocation.
Using and interpreting this tool
Confirm the target and measurement point, then start the checks you need. Results retain sources, observation times and missing-data reasons. Traffic-intensive checks require a separate start.
After changing one setting, start a fresh run and compare A/B snapshots in history. Unknown, unconfigured and inapplicable do not mean passed.
Related tools and guides
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