254.0.0.0 Subnet Mask
254.0.0.0 is the subnet mask for a /7 network — 33,554,430 usable hosts out of 33,554,432 addresses.
CIDR Prefix
/7
Wildcard Mask
1.255.255.255
Total Addresses
33,554,432
Usable Hosts
33,554,430
Network Bits
7
Host Bits
25
254.0.0.0 in Binary
Each octet is eight bits. The highlighted bits are the 7 network bits; the rest are the 25 host bits that vary within the subnet.
254
0
0
0
Networks Using 254.0.0.0
| Network | Host Range | Broadcast |
|---|---|---|
| 10.0.0.0/7 | 10.0.0.1 – 11.255.255.254 | 11.255.255.255 |
| 172.0.0.0/7 | 172.0.0.1 – 173.255.255.254 | 173.255.255.255 |
| 192.0.0.0/7 | 192.0.0.1 – 193.255.255.254 | 193.255.255.255 |
Neighbouring Masks
Frequently Asked Questions
What CIDR prefix is 254.0.0.0?
254.0.0.0 is /7 in CIDR notation. The mask sets the first 7 of the 32 bits in an IPv4 address to 1, marking them as the network portion, and leaves the remaining 25 bits as 0 for hosts.
How many hosts does 254.0.0.0 allow?
A network with mask 254.0.0.0 holds 33,554,432 addresses, of which 33,554,430 are usable by hosts — the network address and the broadcast address are reserved.
What is the wildcard mask for 254.0.0.0?
The wildcard mask for 254.0.0.0 is 1.255.255.255. 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 /7 prefix notation that 254.0.0.0 is equivalent to, and requires masks to be contiguous — which is why exactly 33 of the 4.3 billion possible values are valid.