All questions
Q & A IP & Network · September 11, 2026

Is /32 a valid subnet?

Yes — a /32 is a single-host ‘subnet’ with exactly one address. Used for loopback interfaces, host routes in routing tables, and firewall rules matching a single IP. It’s not a subnet in the traditional sense of holding multiple hosts, but the notation is valid and common.

Read the full guide
CIDR Subnet Math Explained: /24, /16, /8, and Everything Between
CIDR notation is how modern networks are described: an IP address plus a slash and a number counting the network-prefix bits. Everything left of the boundary is the network; everything right is the host. The math is simpler than the notation makes it look.
Related questions
How do I split a /24 into four subnets? How many hosts fit in a /16? What does /24 mean in an IP address? What is the difference between /30 and /31? What is the difference between a public and private IP?