Convert between CIDR prefix notation and dotted-decimal subnet masks.
Free online converter between CIDR prefix length and subnet mask. Enter a CIDR prefix (e.g., /24) to get the netmask, or enter a netmask (e.g., 255.255.255.0) to get the CIDR prefix. Also shows wildcard mask and host counts.
Calculate network details from CIDR notation instantly.
Calculate network address, broadcast, host range, and subnet masks from CIDR notation.
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