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IPv4 Subnet Calculator
Calculate CIDR blocks, masks, ranges, and broadcast addresses locally.
What IPv4 Subnet Calculator does
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IPv4 Subnet Calculator parses CIDR notation locally and calculates the network address, subnet mask, binary mask, wildcard mask, address count, usable host range, broadcast address, IP class, previous block, and next block. Use it for network planning, firewall rules, router notes, and quick subnet checks without sending IP data to a server.