/31 Subnet Mask: 255.255.255.254

Answer
255.255.255.254 · 2 usable hosts

A /31 network uses 31 bits for the network and 1 for hosts, giving 2 addresses and 2 usable hosts. It is typically used for point-to-point links (RFC 3021).

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    /31 at a glance

    PropertyValue
    Subnet mask255.255.255.254
    Wildcard mask0.0.0.1
    Total addresses2
    Usable hosts2
    Size relative to /24128 per /24

    Example: 192.168.1.0/31

    FieldAddress
    Network192.168.1.0
    First host192.168.1.0
    Last host192.168.1.1
    Broadcastn/a

    Frequently asked questions

    How many hosts are in a /31?

    2 usable hosts out of 2 addresses.

    What is the wildcard mask for /31?

    0.0.0.1, the inverse of 255.255.255.254.

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