Calculators
Subnetting, CIDR and address-format conversion. Every one runs in your browser.
- IPv4 subnet calculator
Network, broadcast, usable range and host count from an address and a mask.
- IPv6 subnet calculator
Prefix boundaries and subnet counts for any IPv6 network.
- CIDR ↔ range
Expand a CIDR block to its range, or reduce a range to the fewest blocks that cover it.
- Address converter
Dotted quad, integer, hexadecimal, binary, and IPv4-in-IPv6 forms.
Runs entirely in your browser — nothing you enter is sent to us.