Detailed information about IPv4 /16 subnets
A /16 network (Class B) provides 65,534 usable IP addresses and is suitable for large organizations with multiple departments or campuses.
| CIDR Notation | /16 |
| Subnet Mask | 255.255.0.0 |
| Binary Subnet Mask | 11111111 11111111 00000000 00000000 |
| Total Addresses | 65,536 |
| Usable Hosts (Standard) | 65,534 |
| AWS Usable IPs | 65,529 |
| Azure Usable IPs | 65,529 |
| GCP Usable IPs | 65,530 |
A CIDR /16 subnet has 65,534 usable IP addresses for hosts. This is a relatively large subnet that can be further divided into smaller subnets if needed.
This subnet size strikes a balance between address space efficiency and management overhead.
Cloud providers reserve some IP addresses in each subnet for internal use, resulting in fewer usable IPs:
When planning your cloud infrastructure, consider these reserved addresses to accurately size your subnets.