/2 subnet: mask 192.0.0.0, 1,073,741,824 addresses

Everything about a /2 network, with the CIDR calculator pre-filled — change the IP to calculate your own block.

Enter a CIDR range above to calculate

Is an IP inside a CIDR block?

Yes — 10.0.42.7 is inside 10.0.0.0/16.

Do two CIDR blocks overlap?

Overlap — 10.0.128.0/20 sits inside 10.0.0.0/16 (10.0.128.0 – 10.0.143.255).

CIDR blocks never partly overlap: one is inside the other, or they don't touch at all. Overlapping VPCs can't be peered.

/2 at a glance

Subnet mask
192.0.0.0
Wildcard mask
63.255.255.255
Mask in binary
11000000.00000000.00000000.00000000
Host bits
30
Total addresses
1,073,741,824
Usable hosts
1,073,741,822 (network and broadcast address excluded)
Equivalent /24 networks
4,194,304

Splitting a /2 into smaller subnets

  • 2 × /3 — 536,870,912 addresses each (536,870,910 usable)
  • 4 × /4 — 268,435,456 addresses each (268,435,454 usable)
  • 8 × /5 — 134,217,728 addresses each (134,217,726 usable)
  • 16 × /6 — 67,108,864 addresses each (67,108,862 usable)

Frequently asked

What is the subnet mask for /2?

192.0.0.0. The first 2 bits are network bits and the remaining 30 are host bits; the wildcard (inverse) mask is 63.255.255.255.

How many IP addresses are in a /2?

1,073,741,824 in total. 1,073,741,822 of them can be assigned to hosts, because the first is the network address and the last is the broadcast address.

CIDR to subnet mask cheat sheet

CIDRSubnet maskAddressesUsable hosts
/8255.0.0.016,777,21616,777,214
/12255.240.0.01,048,5761,048,574
/16255.255.0.065,53665,534
/17255.255.128.032,76832,766
/18255.255.192.016,38416,382
/19255.255.224.08,1928,190
/20255.255.240.04,0964,094
/21255.255.248.02,0482,046
/22255.255.252.01,0241,022
/23255.255.254.0512510
/24255.255.255.0256254
/25255.255.255.128128126
/26255.255.255.1926462
/27255.255.255.2243230
/28255.255.255.2401614
/29255.255.255.24886
/30255.255.255.25242
/31255.255.255.25422
/32255.255.255.25511
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