2001:db8::/123 | ip calcalutor | 2001:db8::/123 network number, 2001:db8::/123 netmask address, 2001:db8::/123 broadcast address, 2001:db8::/123 wildcard mask address, whois 2001:db8::/123, 2001:db8::/123 reverse lookup, subnet calc, subcalc, subnetcalc, ipcalc, sipcalc