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IPv4 subnet calculator
CIDR prefix 0–32; /31 and /32 host counts follow common conventions.
Back to homeCIDR prefix 0–32; /31 and /32 host counts follow common conventions.
Back to homeIPv4 + CIDR mask: network, broadcast, first/last host, host count.
/31 and /32 have special cases in RFCs; numbers here are conventional.