subnet.im

/4 Subnet

Subnet Mask

240.0.0.0

Wildcard Mask

15.255.255.255

Total IPs

268,435,456

Usable Hosts

268,435,454

Network Bits

4

Host Bits

28

About /4 Networks

Extremely large allocation, rarely used outside global routing. A /4 subnet uses the mask 240.0.0.0 and provides 268,435,454 usable host addresses out of 268,435,456 total IPs.

Example /4 Networks

NetworkBroadcastFirst HostLast Host
0.0.0.0/415.255.255.2550.0.0.115.255.255.254
160.0.0.0/4175.255.255.255160.0.0.1175.255.255.254
192.0.0.0/4207.255.255.255192.0.0.1207.255.255.254
192.0.0.0/4207.255.255.255192.0.0.1207.255.255.254
0.0.0.0/415.255.255.2550.0.0.115.255.255.254

Splitting a /4 Into Smaller Subnets

A /4 divides evenly into any longer prefix. Each row shows how many subnets of that size fit inside one /4, and how many usable hosts each of them carries.

Subnet SizeHow Many FitMaskUsable Hosts Each
/52 × /5248.0.0.0134,217,726
/64 × /6252.0.0.067,108,862
/78 × /7254.0.0.033,554,430
/816 × /8255.0.0.016,777,214
/932 × /9255.128.0.08,388,606
/1064 × /10255.192.0.04,194,302
/11128 × /11255.224.0.02,097,150
/12256 × /12255.240.0.01,048,574
/13512 × /13255.248.0.0524,286
/141,024 × /14255.252.0.0262,142
/152,048 × /15255.254.0.0131,070
/164,096 × /16255.255.0.065,534
/178,192 × /17255.255.128.032,766
/1816,384 × /18255.255.192.016,382
/1932,768 × /19255.255.224.08,190
/2065,536 × /20255.255.240.04,094
/21131,072 × /21255.255.248.02,046
/22262,144 × /22255.255.252.01,022
/23524,288 × /23255.255.254.0510
/241,048,576 × /24255.255.255.0254
/252,097,152 × /25255.255.255.128126
/264,194,304 × /26255.255.255.19262
/278,388,608 × /27255.255.255.22430
/2816,777,216 × /28255.255.255.24014
/2933,554,432 × /29255.255.255.2486
/3067,108,864 × /30255.255.255.2522
/31134,217,728 × /31255.255.255.2542
/32268,435,456 × /32255.255.255.2551

How Many /4 Subnets Fit in a Larger Network

The same arithmetic read the other way: how many /4 subnets you get when you carve up each of the next larger prefixes.

Parent Network/4 SubnetsMaskTotal IPs
/32 × /4224.0.0.0536,870,912
/24 × /4192.0.0.01,073,741,824
/18 × /4128.0.0.02,147,483,648
/016 × /40.0.0.04,294,967,296

Adjacent CIDRs

Larger network

/3

Mask: 224.0.0.0

Total IPs: 536,870,912

Usable Hosts: 536,870,910

Smaller network

/5

Mask: 248.0.0.0

Total IPs: 134,217,728

Usable Hosts: 134,217,726

Comparing sizes? The full /0 to /32 cheat sheet table puts every prefix side by side.

Frequently Asked Questions

What is a /4 subnet?

A /4 subnet uses the subnet mask 240.0.0.0 with 268,435,454 usable host addresses and 268,435,456 total IP addresses. It has 4 network bits and 28 host bits.

How many hosts in a /4 network?

A /4 network supports 268,435,454 usable hosts out of 268,435,456 total IP addresses. The usable range excludes the network address and broadcast address.

What subnet mask does /4 use?

A /4 subnet uses the mask 240.0.0.0 (wildcard mask 15.255.255.255). This means the first 4 bits identify the network and the remaining 28 bits identify hosts.

How many /6 subnets are in a /4?

One /4 splits into 4 /6 subnets, each with mask 252.0.0.0 and 67,108,862 usable hosts. Every prefix longer than /4 divides it evenly — the full table is above.

How many /4 subnets are in a /3?

A /3 holds 2 /4 subnets. Each step to a shorter prefix doubles that count, because one bit moves from the host portion of the address to the network portion.

Standards

The figures on this page follow from the following specifications rather than from convention.

Calculate 192.168.0.0/4 →