npm

netmask

Generate IP address netmasks and perform subnet calculations

brewmacoslinux
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Source

About

IP address netmask generation utility

Commands

netmask

Examples

Generate netmask for a CIDR notation address$ netmask 192.168.1.0/24
Convert IP range to CIDR notation$ netmask 192.168.1.0 192.168.1.255
Display netmask in multiple formats$ netmask -e 10.0.0.0/8