Feature Description
Subnet Mask Calculator
Convert CIDR, prefix length, and netmask while showing network address, broadcast, and host range.
Convert CIDR, prefix length, and netmask while directly viewing network address, broadcast, and usable host ranges.
Enter a CIDR block directly, or provide an IP address with either a prefix length or a netmask.
Summary
Common use cases
- Use this page when configuring servers, switches, firewalls, or virtual networks and you want to confirm subnets and host ranges quickly.
- It is useful for checking conversions between CIDR, prefix length, and dotted netmask without doing the math by hand.
- For learning networking, preparing interviews, or planning address space, a subnet calculator makes the structure easier to understand than memorizing formulas alone.