subnetctl

IPv4 and IPv6 subnet breakdown, as you type

IPv4 address

Prefix length

/

IPv6 address / prefix

Prefix	Subnet mask	Usable hosts

/64: One LAN segment — the standard subnet size. SLAAC requires it.
/56: Typical home site allocation — 256 × /64.
/48: Typical site or ISP allocation — 65,536 × /64.
/128: A single host — loopback, host routes.

:: replaces one run of all-zero groups, once per address; leading zeros in a group are always optional.

Breakdown

last valid result

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