/29 vs /30 — Subnet Comparison
A /29 subnet is 2× larger than a /30. Every additional bit in the prefix halves the address space — the 1-bit difference between these two means /29 has 21 = 2 times as many addresses.
6 usable hosts — tiny cluster
Typical Uses
- →Small server cluster (web + app + db)
- →Infrastructure management segment
- →Very small office or branch
2 usable hosts — point-to-point link
Typical Uses
- →WAN point-to-point link between routers
- →BGP peering session
- →Dedicated leased line addressing
Key Differences
How 2 /30 Subnets Divide a /29
Example using 10.0.0.0/29 as the parent block.
| # | CIDR | Network | First Usable | Last Usable | Broadcast | Hosts |
|---|---|---|---|---|---|---|
| 1 | 10.0.0.0/30 | 10.0.0.0 | 10.0.0.1 | 10.0.0.2 | 10.0.0.3 | 2 |
| 2 | 10.0.0.4/30 | 10.0.0.4 | 10.0.0.5 | 10.0.0.6 | 10.0.0.7 | 2 |
FAQ
What is the difference between /29 and /30?
A /29 has 6 usable hosts
and a /30 has 2.
The subnet masks differ: /29 uses 255.255.255.248
while /30 uses 255.255.255.252.
Every additional bit in the prefix halves the number of addresses — so the 1-bit gap means
/29 is exactly 2× larger.
How many /30 subnets fit in a /29?
Exactly 2 /30 subnets fit perfectly inside one /29 with no wasted space. To split a /29 into /30s, just increment the last 1 bit of the network address for each new subnet.
Which should I choose?
/29 is typically used for: Tiny server cluster or infra segment. /30 is better for: WAN point-to-point link. Choose the smallest prefix that comfortably fits your host count — over-allocating wastes address space, but under-allocating means painful renumbering later.