/25 Subnet Mask: 255.255.255.128

Answer
255.255.255.128 · 126 usable hosts

A /25 network uses 25 bits for the network and 7 for hosts, giving 128 addresses and 126 usable hosts. It is typically used for splitting a /24 into two halves.

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    /25 at a glance

    PropertyValue
    Subnet mask255.255.255.128
    Wildcard mask0.0.0.127
    Total addresses128
    Usable hosts126
    Size relative to /242 per /24

    Example: 192.168.1.0/25

    FieldAddress
    Network192.168.1.0
    First host192.168.1.1
    Last host192.168.1.126
    Broadcast192.168.1.127

    Frequently asked questions

    How many hosts are in a /25?

    126 usable hosts out of 128 addresses.

    What is the wildcard mask for /25?

    0.0.0.127, the inverse of 255.255.255.128.

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