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IPv4 Range Expander
Find the smallest CIDR block that covers a start and end IPv4 address.
What IPv4 Range Expander does
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IPv4 Range Expander finds the smallest CIDR block that covers a start and end IPv4 address. It shows the original range size, expanded network start, expanded broadcast end, new address count, and CIDR notation for firewall, routing, and allowlist planning.