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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network53.0.192.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
53.0.192.0
Broadcast address
53.0.223.255
First usable
53.0.192.1
Last usable
53.0.223.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Public public
Old class
A (default /8)
As numbers
Hex 3500C000 · Integer 889241600 to 889249791
Reverse DNS zones
192.0.53.in-addr.arpa
193.0.53.in-addr.arpa
194.0.53.in-addr.arpa
195.0.53.in-addr.arpa
196.0.53.in-addr.arpa
197.0.53.in-addr.arpa
198.0.53.in-addr.arpa
199.0.53.in-addr.arpa
200.0.53.in-addr.arpa
201.0.53.in-addr.arpa
202.0.53.in-addr.arpa
203.0.53.in-addr.arpa
204.0.53.in-addr.arpa
205.0.53.in-addr.arpa
206.0.53.in-addr.arpa
207.0.53.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110101.00000000.11000000.0000000053.0.192.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network00110101.00000000.11000000.0000000053.0.192.0
Broadcast00110101.00000000.11011111.1111111153.0.223.255
Split into smaller subnets/27

53.0.192.0/19 makes 256 subnets of /27.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
153.0.192.0/2753.0.192.1 to 53.0.192.3053.0.192.3130
253.0.192.32/2753.0.192.33 to 53.0.192.6253.0.192.6330
353.0.192.64/2753.0.192.65 to 53.0.192.9453.0.192.9530
453.0.192.96/2753.0.192.97 to 53.0.192.12653.0.192.12730
553.0.192.128/2753.0.192.129 to 53.0.192.15853.0.192.15930
653.0.192.160/2753.0.192.161 to 53.0.192.19053.0.192.19130
753.0.192.192/2753.0.192.193 to 53.0.192.22253.0.192.22330
853.0.192.224/2753.0.192.225 to 53.0.192.25453.0.192.25530
953.0.193.0/2753.0.193.1 to 53.0.193.3053.0.193.3130
1053.0.193.32/2753.0.193.33 to 53.0.193.6253.0.193.6330
1153.0.193.64/2753.0.193.65 to 53.0.193.9453.0.193.9530
1253.0.193.96/2753.0.193.97 to 53.0.193.12653.0.193.12730
1353.0.193.128/2753.0.193.129 to 53.0.193.15853.0.193.15930
1453.0.193.160/2753.0.193.161 to 53.0.193.19053.0.193.19130
1553.0.193.192/2753.0.193.193 to 53.0.193.22253.0.193.22330
1653.0.193.224/2753.0.193.225 to 53.0.193.25453.0.193.25530
1753.0.194.0/2753.0.194.1 to 53.0.194.3053.0.194.3130
1853.0.194.32/2753.0.194.33 to 53.0.194.6253.0.194.6330
1953.0.194.64/2753.0.194.65 to 53.0.194.9453.0.194.9530
2053.0.194.96/2753.0.194.97 to 53.0.194.12653.0.194.12730
2153.0.194.128/2753.0.194.129 to 53.0.194.15853.0.194.15930
2253.0.194.160/2753.0.194.161 to 53.0.194.19053.0.194.19130
2353.0.194.192/2753.0.194.193 to 53.0.194.22253.0.194.22330
2453.0.194.224/2753.0.194.225 to 53.0.194.25453.0.194.25530
2553.0.195.0/2753.0.195.1 to 53.0.195.3053.0.195.3130
2653.0.195.32/2753.0.195.33 to 53.0.195.6253.0.195.6330
2753.0.195.64/2753.0.195.65 to 53.0.195.9453.0.195.9530
2853.0.195.96/2753.0.195.97 to 53.0.195.12653.0.195.12730
2953.0.195.128/2753.0.195.129 to 53.0.195.15853.0.195.15930
3053.0.195.160/2753.0.195.161 to 53.0.195.19053.0.195.19130
3153.0.195.192/2753.0.195.193 to 53.0.195.22253.0.195.22330
3253.0.195.224/2753.0.195.225 to 53.0.195.25453.0.195.25530
3353.0.196.0/2753.0.196.1 to 53.0.196.3053.0.196.3130
3453.0.196.32/2753.0.196.33 to 53.0.196.6253.0.196.6330
3553.0.196.64/2753.0.196.65 to 53.0.196.9453.0.196.9530
3653.0.196.96/2753.0.196.97 to 53.0.196.12653.0.196.12730
3753.0.196.128/2753.0.196.129 to 53.0.196.15853.0.196.15930
3853.0.196.160/2753.0.196.161 to 53.0.196.19053.0.196.19130
3953.0.196.192/2753.0.196.193 to 53.0.196.22253.0.196.22330
4053.0.196.224/2753.0.196.225 to 53.0.196.25453.0.196.25530
4153.0.197.0/2753.0.197.1 to 53.0.197.3053.0.197.3130
4253.0.197.32/2753.0.197.33 to 53.0.197.6253.0.197.6330
4353.0.197.64/2753.0.197.65 to 53.0.197.9453.0.197.9530
4453.0.197.96/2753.0.197.97 to 53.0.197.12653.0.197.12730
4553.0.197.128/2753.0.197.129 to 53.0.197.15853.0.197.15930
4653.0.197.160/2753.0.197.161 to 53.0.197.19053.0.197.19130
4753.0.197.192/2753.0.197.193 to 53.0.197.22253.0.197.22330
4853.0.197.224/2753.0.197.225 to 53.0.197.25453.0.197.25530
4953.0.198.0/2753.0.198.1 to 53.0.198.3053.0.198.3130
5053.0.198.32/2753.0.198.33 to 53.0.198.6253.0.198.6330
5153.0.198.64/2753.0.198.65 to 53.0.198.9453.0.198.9530
5253.0.198.96/2753.0.198.97 to 53.0.198.12653.0.198.12730
5353.0.198.128/2753.0.198.129 to 53.0.198.15853.0.198.15930
5453.0.198.160/2753.0.198.161 to 53.0.198.19053.0.198.19130
5553.0.198.192/2753.0.198.193 to 53.0.198.22253.0.198.22330
5653.0.198.224/2753.0.198.225 to 53.0.198.25453.0.198.25530
5753.0.199.0/2753.0.199.1 to 53.0.199.3053.0.199.3130
5853.0.199.32/2753.0.199.33 to 53.0.199.6253.0.199.6330
5953.0.199.64/2753.0.199.65 to 53.0.199.9453.0.199.9530
6053.0.199.96/2753.0.199.97 to 53.0.199.12653.0.199.12730
6153.0.199.128/2753.0.199.129 to 53.0.199.15853.0.199.15930
6253.0.199.160/2753.0.199.161 to 53.0.199.19053.0.199.19130
6353.0.199.192/2753.0.199.193 to 53.0.199.22253.0.199.22330
6453.0.199.224/2753.0.199.225 to 53.0.199.25453.0.199.25530
6553.0.200.0/2753.0.200.1 to 53.0.200.3053.0.200.3130
6653.0.200.32/2753.0.200.33 to 53.0.200.6253.0.200.6330
6753.0.200.64/2753.0.200.65 to 53.0.200.9453.0.200.9530
6853.0.200.96/2753.0.200.97 to 53.0.200.12653.0.200.12730
6953.0.200.128/2753.0.200.129 to 53.0.200.15853.0.200.15930
7053.0.200.160/2753.0.200.161 to 53.0.200.19053.0.200.19130
7153.0.200.192/2753.0.200.193 to 53.0.200.22253.0.200.22330
7253.0.200.224/2753.0.200.225 to 53.0.200.25453.0.200.25530
7353.0.201.0/2753.0.201.1 to 53.0.201.3053.0.201.3130
7453.0.201.32/2753.0.201.33 to 53.0.201.6253.0.201.6330
7553.0.201.64/2753.0.201.65 to 53.0.201.9453.0.201.9530
7653.0.201.96/2753.0.201.97 to 53.0.201.12653.0.201.12730
7753.0.201.128/2753.0.201.129 to 53.0.201.15853.0.201.15930
7853.0.201.160/2753.0.201.161 to 53.0.201.19053.0.201.19130
7953.0.201.192/2753.0.201.193 to 53.0.201.22253.0.201.22330
8053.0.201.224/2753.0.201.225 to 53.0.201.25453.0.201.25530
8153.0.202.0/2753.0.202.1 to 53.0.202.3053.0.202.3130
8253.0.202.32/2753.0.202.33 to 53.0.202.6253.0.202.6330
8353.0.202.64/2753.0.202.65 to 53.0.202.9453.0.202.9530
8453.0.202.96/2753.0.202.97 to 53.0.202.12653.0.202.12730
8553.0.202.128/2753.0.202.129 to 53.0.202.15853.0.202.15930
8653.0.202.160/2753.0.202.161 to 53.0.202.19053.0.202.19130
8753.0.202.192/2753.0.202.193 to 53.0.202.22253.0.202.22330
8853.0.202.224/2753.0.202.225 to 53.0.202.25453.0.202.25530
8953.0.203.0/2753.0.203.1 to 53.0.203.3053.0.203.3130
9053.0.203.32/2753.0.203.33 to 53.0.203.6253.0.203.6330
9153.0.203.64/2753.0.203.65 to 53.0.203.9453.0.203.9530
9253.0.203.96/2753.0.203.97 to 53.0.203.12653.0.203.12730
9353.0.203.128/2753.0.203.129 to 53.0.203.15853.0.203.15930
9453.0.203.160/2753.0.203.161 to 53.0.203.19053.0.203.19130
9553.0.203.192/2753.0.203.193 to 53.0.203.22253.0.203.22330
9653.0.203.224/2753.0.203.225 to 53.0.203.25453.0.203.25530
9753.0.204.0/2753.0.204.1 to 53.0.204.3053.0.204.3130
9853.0.204.32/2753.0.204.33 to 53.0.204.6253.0.204.6330
9953.0.204.64/2753.0.204.65 to 53.0.204.9453.0.204.9530
10053.0.204.96/2753.0.204.97 to 53.0.204.12653.0.204.12730
10153.0.204.128/2753.0.204.129 to 53.0.204.15853.0.204.15930
10253.0.204.160/2753.0.204.161 to 53.0.204.19053.0.204.19130
10353.0.204.192/2753.0.204.193 to 53.0.204.22253.0.204.22330
10453.0.204.224/2753.0.204.225 to 53.0.204.25453.0.204.25530
10553.0.205.0/2753.0.205.1 to 53.0.205.3053.0.205.3130
10653.0.205.32/2753.0.205.33 to 53.0.205.6253.0.205.6330
10753.0.205.64/2753.0.205.65 to 53.0.205.9453.0.205.9530
10853.0.205.96/2753.0.205.97 to 53.0.205.12653.0.205.12730
10953.0.205.128/2753.0.205.129 to 53.0.205.15853.0.205.15930
11053.0.205.160/2753.0.205.161 to 53.0.205.19053.0.205.19130
11153.0.205.192/2753.0.205.193 to 53.0.205.22253.0.205.22330
11253.0.205.224/2753.0.205.225 to 53.0.205.25453.0.205.25530
11353.0.206.0/2753.0.206.1 to 53.0.206.3053.0.206.3130
11453.0.206.32/2753.0.206.33 to 53.0.206.6253.0.206.6330
11553.0.206.64/2753.0.206.65 to 53.0.206.9453.0.206.9530
11653.0.206.96/2753.0.206.97 to 53.0.206.12653.0.206.12730
11753.0.206.128/2753.0.206.129 to 53.0.206.15853.0.206.15930
11853.0.206.160/2753.0.206.161 to 53.0.206.19053.0.206.19130
11953.0.206.192/2753.0.206.193 to 53.0.206.22253.0.206.22330
12053.0.206.224/2753.0.206.225 to 53.0.206.25453.0.206.25530
12153.0.207.0/2753.0.207.1 to 53.0.207.3053.0.207.3130
12253.0.207.32/2753.0.207.33 to 53.0.207.6253.0.207.6330
12353.0.207.64/2753.0.207.65 to 53.0.207.9453.0.207.9530
12453.0.207.96/2753.0.207.97 to 53.0.207.12653.0.207.12730
12553.0.207.128/2753.0.207.129 to 53.0.207.15853.0.207.15930
12653.0.207.160/2753.0.207.161 to 53.0.207.19053.0.207.19130
12753.0.207.192/2753.0.207.193 to 53.0.207.22253.0.207.22330
12853.0.207.224/2753.0.207.225 to 53.0.207.25453.0.207.25530
12953.0.208.0/2753.0.208.1 to 53.0.208.3053.0.208.3130
13053.0.208.32/2753.0.208.33 to 53.0.208.6253.0.208.6330
13153.0.208.64/2753.0.208.65 to 53.0.208.9453.0.208.9530
13253.0.208.96/2753.0.208.97 to 53.0.208.12653.0.208.12730
13353.0.208.128/2753.0.208.129 to 53.0.208.15853.0.208.15930
13453.0.208.160/2753.0.208.161 to 53.0.208.19053.0.208.19130
13553.0.208.192/2753.0.208.193 to 53.0.208.22253.0.208.22330
13653.0.208.224/2753.0.208.225 to 53.0.208.25453.0.208.25530
13753.0.209.0/2753.0.209.1 to 53.0.209.3053.0.209.3130
13853.0.209.32/2753.0.209.33 to 53.0.209.6253.0.209.6330
13953.0.209.64/2753.0.209.65 to 53.0.209.9453.0.209.9530
14053.0.209.96/2753.0.209.97 to 53.0.209.12653.0.209.12730
14153.0.209.128/2753.0.209.129 to 53.0.209.15853.0.209.15930
14253.0.209.160/2753.0.209.161 to 53.0.209.19053.0.209.19130
14353.0.209.192/2753.0.209.193 to 53.0.209.22253.0.209.22330
14453.0.209.224/2753.0.209.225 to 53.0.209.25453.0.209.25530
14553.0.210.0/2753.0.210.1 to 53.0.210.3053.0.210.3130
14653.0.210.32/2753.0.210.33 to 53.0.210.6253.0.210.6330
14753.0.210.64/2753.0.210.65 to 53.0.210.9453.0.210.9530
14853.0.210.96/2753.0.210.97 to 53.0.210.12653.0.210.12730
14953.0.210.128/2753.0.210.129 to 53.0.210.15853.0.210.15930
15053.0.210.160/2753.0.210.161 to 53.0.210.19053.0.210.19130
15153.0.210.192/2753.0.210.193 to 53.0.210.22253.0.210.22330
15253.0.210.224/2753.0.210.225 to 53.0.210.25453.0.210.25530
15353.0.211.0/2753.0.211.1 to 53.0.211.3053.0.211.3130
15453.0.211.32/2753.0.211.33 to 53.0.211.6253.0.211.6330
15553.0.211.64/2753.0.211.65 to 53.0.211.9453.0.211.9530
15653.0.211.96/2753.0.211.97 to 53.0.211.12653.0.211.12730
15753.0.211.128/2753.0.211.129 to 53.0.211.15853.0.211.15930
15853.0.211.160/2753.0.211.161 to 53.0.211.19053.0.211.19130
15953.0.211.192/2753.0.211.193 to 53.0.211.22253.0.211.22330
16053.0.211.224/2753.0.211.225 to 53.0.211.25453.0.211.25530
16153.0.212.0/2753.0.212.1 to 53.0.212.3053.0.212.3130
16253.0.212.32/2753.0.212.33 to 53.0.212.6253.0.212.6330
16353.0.212.64/2753.0.212.65 to 53.0.212.9453.0.212.9530
16453.0.212.96/2753.0.212.97 to 53.0.212.12653.0.212.12730
16553.0.212.128/2753.0.212.129 to 53.0.212.15853.0.212.15930
16653.0.212.160/2753.0.212.161 to 53.0.212.19053.0.212.19130
16753.0.212.192/2753.0.212.193 to 53.0.212.22253.0.212.22330
16853.0.212.224/2753.0.212.225 to 53.0.212.25453.0.212.25530
16953.0.213.0/2753.0.213.1 to 53.0.213.3053.0.213.3130
17053.0.213.32/2753.0.213.33 to 53.0.213.6253.0.213.6330
17153.0.213.64/2753.0.213.65 to 53.0.213.9453.0.213.9530
17253.0.213.96/2753.0.213.97 to 53.0.213.12653.0.213.12730
17353.0.213.128/2753.0.213.129 to 53.0.213.15853.0.213.15930
17453.0.213.160/2753.0.213.161 to 53.0.213.19053.0.213.19130
17553.0.213.192/2753.0.213.193 to 53.0.213.22253.0.213.22330
17653.0.213.224/2753.0.213.225 to 53.0.213.25453.0.213.25530
17753.0.214.0/2753.0.214.1 to 53.0.214.3053.0.214.3130
17853.0.214.32/2753.0.214.33 to 53.0.214.6253.0.214.6330
17953.0.214.64/2753.0.214.65 to 53.0.214.9453.0.214.9530
18053.0.214.96/2753.0.214.97 to 53.0.214.12653.0.214.12730
18153.0.214.128/2753.0.214.129 to 53.0.214.15853.0.214.15930
18253.0.214.160/2753.0.214.161 to 53.0.214.19053.0.214.19130
18353.0.214.192/2753.0.214.193 to 53.0.214.22253.0.214.22330
18453.0.214.224/2753.0.214.225 to 53.0.214.25453.0.214.25530
18553.0.215.0/2753.0.215.1 to 53.0.215.3053.0.215.3130
18653.0.215.32/2753.0.215.33 to 53.0.215.6253.0.215.6330
18753.0.215.64/2753.0.215.65 to 53.0.215.9453.0.215.9530
18853.0.215.96/2753.0.215.97 to 53.0.215.12653.0.215.12730
18953.0.215.128/2753.0.215.129 to 53.0.215.15853.0.215.15930
19053.0.215.160/2753.0.215.161 to 53.0.215.19053.0.215.19130
19153.0.215.192/2753.0.215.193 to 53.0.215.22253.0.215.22330
19253.0.215.224/2753.0.215.225 to 53.0.215.25453.0.215.25530
19353.0.216.0/2753.0.216.1 to 53.0.216.3053.0.216.3130
19453.0.216.32/2753.0.216.33 to 53.0.216.6253.0.216.6330
19553.0.216.64/2753.0.216.65 to 53.0.216.9453.0.216.9530
19653.0.216.96/2753.0.216.97 to 53.0.216.12653.0.216.12730
19753.0.216.128/2753.0.216.129 to 53.0.216.15853.0.216.15930
19853.0.216.160/2753.0.216.161 to 53.0.216.19053.0.216.19130
19953.0.216.192/2753.0.216.193 to 53.0.216.22253.0.216.22330
20053.0.216.224/2753.0.216.225 to 53.0.216.25453.0.216.25530
20153.0.217.0/2753.0.217.1 to 53.0.217.3053.0.217.3130
20253.0.217.32/2753.0.217.33 to 53.0.217.6253.0.217.6330
20353.0.217.64/2753.0.217.65 to 53.0.217.9453.0.217.9530
20453.0.217.96/2753.0.217.97 to 53.0.217.12653.0.217.12730
20553.0.217.128/2753.0.217.129 to 53.0.217.15853.0.217.15930
20653.0.217.160/2753.0.217.161 to 53.0.217.19053.0.217.19130
20753.0.217.192/2753.0.217.193 to 53.0.217.22253.0.217.22330
20853.0.217.224/2753.0.217.225 to 53.0.217.25453.0.217.25530
20953.0.218.0/2753.0.218.1 to 53.0.218.3053.0.218.3130
21053.0.218.32/2753.0.218.33 to 53.0.218.6253.0.218.6330
21153.0.218.64/2753.0.218.65 to 53.0.218.9453.0.218.9530
21253.0.218.96/2753.0.218.97 to 53.0.218.12653.0.218.12730
21353.0.218.128/2753.0.218.129 to 53.0.218.15853.0.218.15930
21453.0.218.160/2753.0.218.161 to 53.0.218.19053.0.218.19130
21553.0.218.192/2753.0.218.193 to 53.0.218.22253.0.218.22330
21653.0.218.224/2753.0.218.225 to 53.0.218.25453.0.218.25530
21753.0.219.0/2753.0.219.1 to 53.0.219.3053.0.219.3130
21853.0.219.32/2753.0.219.33 to 53.0.219.6253.0.219.6330
21953.0.219.64/2753.0.219.65 to 53.0.219.9453.0.219.9530
22053.0.219.96/2753.0.219.97 to 53.0.219.12653.0.219.12730
22153.0.219.128/2753.0.219.129 to 53.0.219.15853.0.219.15930
22253.0.219.160/2753.0.219.161 to 53.0.219.19053.0.219.19130
22353.0.219.192/2753.0.219.193 to 53.0.219.22253.0.219.22330
22453.0.219.224/2753.0.219.225 to 53.0.219.25453.0.219.25530
22553.0.220.0/2753.0.220.1 to 53.0.220.3053.0.220.3130
22653.0.220.32/2753.0.220.33 to 53.0.220.6253.0.220.6330
22753.0.220.64/2753.0.220.65 to 53.0.220.9453.0.220.9530
22853.0.220.96/2753.0.220.97 to 53.0.220.12653.0.220.12730
22953.0.220.128/2753.0.220.129 to 53.0.220.15853.0.220.15930
23053.0.220.160/2753.0.220.161 to 53.0.220.19053.0.220.19130
23153.0.220.192/2753.0.220.193 to 53.0.220.22253.0.220.22330
23253.0.220.224/2753.0.220.225 to 53.0.220.25453.0.220.25530
23353.0.221.0/2753.0.221.1 to 53.0.221.3053.0.221.3130
23453.0.221.32/2753.0.221.33 to 53.0.221.6253.0.221.6330
23553.0.221.64/2753.0.221.65 to 53.0.221.9453.0.221.9530
23653.0.221.96/2753.0.221.97 to 53.0.221.12653.0.221.12730
23753.0.221.128/2753.0.221.129 to 53.0.221.15853.0.221.15930
23853.0.221.160/2753.0.221.161 to 53.0.221.19053.0.221.19130
23953.0.221.192/2753.0.221.193 to 53.0.221.22253.0.221.22330
24053.0.221.224/2753.0.221.225 to 53.0.221.25453.0.221.25530
24153.0.222.0/2753.0.222.1 to 53.0.222.3053.0.222.3130
24253.0.222.32/2753.0.222.33 to 53.0.222.6253.0.222.6330
24353.0.222.64/2753.0.222.65 to 53.0.222.9453.0.222.9530
24453.0.222.96/2753.0.222.97 to 53.0.222.12653.0.222.12730
24553.0.222.128/2753.0.222.129 to 53.0.222.15853.0.222.15930
24653.0.222.160/2753.0.222.161 to 53.0.222.19053.0.222.19130
24753.0.222.192/2753.0.222.193 to 53.0.222.22253.0.222.22330
24853.0.222.224/2753.0.222.225 to 53.0.222.25453.0.222.25530
24953.0.223.0/2753.0.223.1 to 53.0.223.3053.0.223.3130
25053.0.223.32/2753.0.223.33 to 53.0.223.6253.0.223.6330
25153.0.223.64/2753.0.223.65 to 53.0.223.9453.0.223.9530
25253.0.223.96/2753.0.223.97 to 53.0.223.12653.0.223.12730
25353.0.223.128/2753.0.223.129 to 53.0.223.15853.0.223.15930
25453.0.223.160/2753.0.223.161 to 53.0.223.19053.0.223.19130
25553.0.223.192/2753.0.223.193 to 53.0.223.22253.0.223.22330
25653.0.223.224/2753.0.223.225 to 53.0.223.25453.0.223.25530

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses