255.255.255.252 Subnet Mask
255.255.255.252 is the subnet mask for a /30 network — 2 usable hosts out of 4 addresses.
CIDR Prefix
/30
Wildcard Mask
0.0.0.3
Total Addresses
4
Usable Hosts
2
Network Bits
30
Host Bits
2
255.255.255.252 in Binary
Each octet is eight bits. The highlighted bits are the 30 network bits; the rest are the 2 host bits that vary within the subnet.
255
255
255
252
Networks Using 255.255.255.252
| Network | Host Range | Broadcast |
|---|---|---|
| 10.0.0.0/30 | 10.0.0.1 – 10.0.0.2 | 10.0.0.3 |
| 172.16.0.0/30 | 172.16.0.1 – 172.16.0.2 | 172.16.0.3 |
| 192.168.1.0/30 | 192.168.1.1 – 192.168.1.2 | 192.168.1.3 |
Neighbouring Masks
Frequently Asked Questions
What CIDR prefix is 255.255.255.252?
255.255.255.252 is /30 in CIDR notation. The mask sets the first 30 of the 32 bits in an IPv4 address to 1, marking them as the network portion, and leaves the remaining 2 bits as 0 for hosts.
How many hosts does 255.255.255.252 allow?
A network with mask 255.255.255.252 holds 4 addresses, of which 2 are usable by hosts — the network address and the broadcast address are reserved.
What is the wildcard mask for 255.255.255.252?
The wildcard mask for 255.255.255.252 is 0.0.0.3. It is the bitwise inverse: every 1 in the subnet mask becomes a 0 and every 0 becomes a 1. Cisco access lists and OSPF network statements take the wildcard form rather than the subnet mask.
Standards
- RFC 950 — Internet Standard Subnetting Procedure
Defines the dotted-decimal subnet mask itself, and the rule that the network and broadcast addresses are not assignable to hosts.
- RFC 4632 — Classless Inter-Domain Routing (CIDR)
Establishes the /30 prefix notation that 255.255.255.252 is equivalent to, and requires masks to be contiguous — which is why exactly 33 of the 4.3 billion possible values are valid.