Free IP Subnet Calculator for IPv4 and IPv6
This free online IP subnet calculator supports both IPv4 and IPv6 addresses.
Enter any IP address in CIDR notation (e.g. 192.168.1.50/24 or 2001:db8::1/48)
and instantly get the network address, broadcast address,
usable host IP range, subnet mask, wildcard mask,
IP class, CIDR notation, and binary representation.
The tool also lists all possible subnets of the same prefix length within the containing network block —
for example, all 64 possible /30 networks within a /24 network.
Results can be exported directly to Excel (.xlsx).
Supported Input Formats
- CIDR notation:
192.168.1.1/24
- IP with subnet mask:
192.168.1.1 255.255.255.0
- IPv6 with prefix:
2001:db8::1/48
What This Calculator Provides
- Network address and broadcast address
- First and last usable host IP addresses
- Total and usable host counts
- Subnet mask and wildcard mask
- Binary subnet mask representation
- IP class (A, B, C, D, E) and IP type (Public, Private, Loopback, Link-local, Multicast)
- Binary ID, Integer ID, Hex ID, in-addr.arpa reverse DNS
- IPv4-mapped address and 6to4 prefix
- All possible subnets within the containing /24, /16, or /8 block
- IPv6: full expanded address, total address count, IP range, IP type (Global Unicast, ULA, Link-local, etc.)