CIDR Calculator

Decode any IPv4 CIDR into its network, broadcast, and usable host range. 100% client-side.

Subnet & Range Input

CIDR

Quick picks

Network10.0.0.0

Broadcast10.0.0.255

First usable10.0.0.1

Last usable10.0.0.254

Subnet mask255.255.255.0

Prefix/24

Usable hosts254

Total hosts256

VisibilityPrivate

Expand lists every address (prefixes /24 and shorter only).

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