/19 Subnet
8,192 total IPs — 8,190 usable hosts.
Example /19 Networks
| CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|
| 10.0.0.0/19 | 10.0.0.0 | 10.0.0.1 | 10.0.31.254 | 10.0.31.255 | 8,190 |
| 172.16.0.0/19 | 172.16.0.0 | 172.16.0.1 | 172.16.31.254 | 172.16.31.255 | 8,190 |
| 172.31.0.0/19 | 172.31.0.0 | 172.31.0.1 | 172.31.31.254 | 172.31.31.255 | 8,190 |
| 192.168.0.0/19 | 192.168.0.0 | 192.168.0.1 | 192.168.31.254 | 192.168.31.255 | 8,190 |
| 192.168.0.0/19 | 192.168.0.0 | 192.168.0.1 | 192.168.31.254 | 192.168.31.255 | 8,190 |
| 10.0.0.0/19 | 10.0.0.0 | 10.0.0.1 | 10.0.31.254 | 10.0.31.255 | 8,190 |
How /19 Compares
| Prefix | Total IPs | Usable Hosts | Subnet Mask | Typical Use |
|---|---|---|---|---|
| /16 | 65,536 | 65,534 | 255.255.0.0 | Cloud VPC CIDR, campus network |
| /17 | 32,768 | 32,766 | 255.255.128.0 | Large segment within a /16 |
| /18 | 16,384 | 16,382 | 255.255.192.0 | VPC segment |
| /19 ◀ | 8,192 | 8,190 | 255.255.224.0 | — |
| /20 | 4,096 | 4,094 | 255.255.240.0 | AWS default subnet, medium office VLAN |
| /21 | 2,048 | 2,046 | 255.255.248.0 | Enterprise building / large app tier |
| /22 | 1,024 | 1,022 | 255.255.252.0 | Medium office/application segment |
Frequently Asked Questions
How many IPs are in a /19?
A /19 subnet contains 8,192 total IP addresses and 8,190 usable host addresses. The network address (first IP) and broadcast address (last IP) are reserved and cannot be assigned to hosts.
What is the subnet mask for /19?
The subnet mask for a /19 is 255.255.224.0.
In CIDR notation, the prefix length /19 means
the first 19 bits of the address are the network portion.
The wildcard (inverse) mask is 0.0.31.255.
How many /19 subnets fit in a /18?
Exactly 2 — a /18 can be split into two /19 subnets of equal size. Each /19 subnet has 8,190 usable hosts, compared to 16,382 in the parent /18.