Subnet Calculator (IPv4/CIDR) →
Network, broadcast, host range, mask, wildcard, scope detection and a subnet splitter — live.
LookupWhat Is My IP? →
Instantly see your public IP, version, scope and reverse DNS — read from your connection, no trackers.
LookupDNS Lookup (Domain → IP) →
Resolve any domain to its IP and DNS records — A, AAAA, CNAME, MX, NS, TXT — live.
PlannerVLSM Calculator →
Divide a network into right-sized subnets from your required host counts, largest-first.
CalculatorCIDR Calculator →
CIDR ↔ subnet mask ↔ address range ↔ host count, with the bit-level breakdown.
IPv6IPv6 Subnet Calculator →
Compress/expand (RFC 5952), prefix maths, /64 counts and scope for IPv6.
ConverterIP Address Converter →
Dotted ↔ integer ↔ hex ↔ binary, with scope detection.
ReferenceSubnet Cheat Sheet →
Every CIDR prefix → subnet mask, wildcard, hosts and total addresses, in one table.
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