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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.

Network55.2.4.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
55.2.4.0
Broadcast address
55.2.7.255
First usable
55.2.4.1
Last usable
55.2.7.254
Usable hosts
1,022 (1,024 less the network and broadcast addresses)
Subnet mask
255.255.252.0
Wildcard mask
0.0.3.255 (Cisco ACLs, OSPF)
Prefix length
/22
Type
Public public
Old class
A (default /8)
As numbers
Hex 37020400 · Integer 922878976 to 922879999
Reverse DNS zones
4.2.55.in-addr.arpa
5.2.55.in-addr.arpa
6.2.55.in-addr.arpa
7.2.55.in-addr.arpa
/22 is not on a 8-bit boundary, so it takes 4 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110111.00000010.00000100.0000000055.2.4.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00110111.00000010.00000100.0000000055.2.4.0
Broadcast00110111.00000010.00000111.1111111155.2.7.255
Split into smaller subnets/30

55.2.4.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
155.2.4.0/3055.2.4.1 to 55.2.4.255.2.4.32
255.2.4.4/3055.2.4.5 to 55.2.4.655.2.4.72
355.2.4.8/3055.2.4.9 to 55.2.4.1055.2.4.112
455.2.4.12/3055.2.4.13 to 55.2.4.1455.2.4.152
555.2.4.16/3055.2.4.17 to 55.2.4.1855.2.4.192
655.2.4.20/3055.2.4.21 to 55.2.4.2255.2.4.232
755.2.4.24/3055.2.4.25 to 55.2.4.2655.2.4.272
855.2.4.28/3055.2.4.29 to 55.2.4.3055.2.4.312
955.2.4.32/3055.2.4.33 to 55.2.4.3455.2.4.352
1055.2.4.36/3055.2.4.37 to 55.2.4.3855.2.4.392
1155.2.4.40/3055.2.4.41 to 55.2.4.4255.2.4.432
1255.2.4.44/3055.2.4.45 to 55.2.4.4655.2.4.472
1355.2.4.48/3055.2.4.49 to 55.2.4.5055.2.4.512
1455.2.4.52/3055.2.4.53 to 55.2.4.5455.2.4.552
1555.2.4.56/3055.2.4.57 to 55.2.4.5855.2.4.592
1655.2.4.60/3055.2.4.61 to 55.2.4.6255.2.4.632
1755.2.4.64/3055.2.4.65 to 55.2.4.6655.2.4.672
1855.2.4.68/3055.2.4.69 to 55.2.4.7055.2.4.712
1955.2.4.72/3055.2.4.73 to 55.2.4.7455.2.4.752
2055.2.4.76/3055.2.4.77 to 55.2.4.7855.2.4.792
2155.2.4.80/3055.2.4.81 to 55.2.4.8255.2.4.832
2255.2.4.84/3055.2.4.85 to 55.2.4.8655.2.4.872
2355.2.4.88/3055.2.4.89 to 55.2.4.9055.2.4.912
2455.2.4.92/3055.2.4.93 to 55.2.4.9455.2.4.952
2555.2.4.96/3055.2.4.97 to 55.2.4.9855.2.4.992
2655.2.4.100/3055.2.4.101 to 55.2.4.10255.2.4.1032
2755.2.4.104/3055.2.4.105 to 55.2.4.10655.2.4.1072
2855.2.4.108/3055.2.4.109 to 55.2.4.11055.2.4.1112
2955.2.4.112/3055.2.4.113 to 55.2.4.11455.2.4.1152
3055.2.4.116/3055.2.4.117 to 55.2.4.11855.2.4.1192
3155.2.4.120/3055.2.4.121 to 55.2.4.12255.2.4.1232
3255.2.4.124/3055.2.4.125 to 55.2.4.12655.2.4.1272
3355.2.4.128/3055.2.4.129 to 55.2.4.13055.2.4.1312
3455.2.4.132/3055.2.4.133 to 55.2.4.13455.2.4.1352
3555.2.4.136/3055.2.4.137 to 55.2.4.13855.2.4.1392
3655.2.4.140/3055.2.4.141 to 55.2.4.14255.2.4.1432
3755.2.4.144/3055.2.4.145 to 55.2.4.14655.2.4.1472
3855.2.4.148/3055.2.4.149 to 55.2.4.15055.2.4.1512
3955.2.4.152/3055.2.4.153 to 55.2.4.15455.2.4.1552
4055.2.4.156/3055.2.4.157 to 55.2.4.15855.2.4.1592
4155.2.4.160/3055.2.4.161 to 55.2.4.16255.2.4.1632
4255.2.4.164/3055.2.4.165 to 55.2.4.16655.2.4.1672
4355.2.4.168/3055.2.4.169 to 55.2.4.17055.2.4.1712
4455.2.4.172/3055.2.4.173 to 55.2.4.17455.2.4.1752
4555.2.4.176/3055.2.4.177 to 55.2.4.17855.2.4.1792
4655.2.4.180/3055.2.4.181 to 55.2.4.18255.2.4.1832
4755.2.4.184/3055.2.4.185 to 55.2.4.18655.2.4.1872
4855.2.4.188/3055.2.4.189 to 55.2.4.19055.2.4.1912
4955.2.4.192/3055.2.4.193 to 55.2.4.19455.2.4.1952
5055.2.4.196/3055.2.4.197 to 55.2.4.19855.2.4.1992
5155.2.4.200/3055.2.4.201 to 55.2.4.20255.2.4.2032
5255.2.4.204/3055.2.4.205 to 55.2.4.20655.2.4.2072
5355.2.4.208/3055.2.4.209 to 55.2.4.21055.2.4.2112
5455.2.4.212/3055.2.4.213 to 55.2.4.21455.2.4.2152
5555.2.4.216/3055.2.4.217 to 55.2.4.21855.2.4.2192
5655.2.4.220/3055.2.4.221 to 55.2.4.22255.2.4.2232
5755.2.4.224/3055.2.4.225 to 55.2.4.22655.2.4.2272
5855.2.4.228/3055.2.4.229 to 55.2.4.23055.2.4.2312
5955.2.4.232/3055.2.4.233 to 55.2.4.23455.2.4.2352
6055.2.4.236/3055.2.4.237 to 55.2.4.23855.2.4.2392
6155.2.4.240/3055.2.4.241 to 55.2.4.24255.2.4.2432
6255.2.4.244/3055.2.4.245 to 55.2.4.24655.2.4.2472
6355.2.4.248/3055.2.4.249 to 55.2.4.25055.2.4.2512
6455.2.4.252/3055.2.4.253 to 55.2.4.25455.2.4.2552
6555.2.5.0/3055.2.5.1 to 55.2.5.255.2.5.32
6655.2.5.4/3055.2.5.5 to 55.2.5.655.2.5.72
6755.2.5.8/3055.2.5.9 to 55.2.5.1055.2.5.112
6855.2.5.12/3055.2.5.13 to 55.2.5.1455.2.5.152
6955.2.5.16/3055.2.5.17 to 55.2.5.1855.2.5.192
7055.2.5.20/3055.2.5.21 to 55.2.5.2255.2.5.232
7155.2.5.24/3055.2.5.25 to 55.2.5.2655.2.5.272
7255.2.5.28/3055.2.5.29 to 55.2.5.3055.2.5.312
7355.2.5.32/3055.2.5.33 to 55.2.5.3455.2.5.352
7455.2.5.36/3055.2.5.37 to 55.2.5.3855.2.5.392
7555.2.5.40/3055.2.5.41 to 55.2.5.4255.2.5.432
7655.2.5.44/3055.2.5.45 to 55.2.5.4655.2.5.472
7755.2.5.48/3055.2.5.49 to 55.2.5.5055.2.5.512
7855.2.5.52/3055.2.5.53 to 55.2.5.5455.2.5.552
7955.2.5.56/3055.2.5.57 to 55.2.5.5855.2.5.592
8055.2.5.60/3055.2.5.61 to 55.2.5.6255.2.5.632
8155.2.5.64/3055.2.5.65 to 55.2.5.6655.2.5.672
8255.2.5.68/3055.2.5.69 to 55.2.5.7055.2.5.712
8355.2.5.72/3055.2.5.73 to 55.2.5.7455.2.5.752
8455.2.5.76/3055.2.5.77 to 55.2.5.7855.2.5.792
8555.2.5.80/3055.2.5.81 to 55.2.5.8255.2.5.832
8655.2.5.84/3055.2.5.85 to 55.2.5.8655.2.5.872
8755.2.5.88/3055.2.5.89 to 55.2.5.9055.2.5.912
8855.2.5.92/3055.2.5.93 to 55.2.5.9455.2.5.952
8955.2.5.96/3055.2.5.97 to 55.2.5.9855.2.5.992
9055.2.5.100/3055.2.5.101 to 55.2.5.10255.2.5.1032
9155.2.5.104/3055.2.5.105 to 55.2.5.10655.2.5.1072
9255.2.5.108/3055.2.5.109 to 55.2.5.11055.2.5.1112
9355.2.5.112/3055.2.5.113 to 55.2.5.11455.2.5.1152
9455.2.5.116/3055.2.5.117 to 55.2.5.11855.2.5.1192
9555.2.5.120/3055.2.5.121 to 55.2.5.12255.2.5.1232
9655.2.5.124/3055.2.5.125 to 55.2.5.12655.2.5.1272
9755.2.5.128/3055.2.5.129 to 55.2.5.13055.2.5.1312
9855.2.5.132/3055.2.5.133 to 55.2.5.13455.2.5.1352
9955.2.5.136/3055.2.5.137 to 55.2.5.13855.2.5.1392
10055.2.5.140/3055.2.5.141 to 55.2.5.14255.2.5.1432
10155.2.5.144/3055.2.5.145 to 55.2.5.14655.2.5.1472
10255.2.5.148/3055.2.5.149 to 55.2.5.15055.2.5.1512
10355.2.5.152/3055.2.5.153 to 55.2.5.15455.2.5.1552
10455.2.5.156/3055.2.5.157 to 55.2.5.15855.2.5.1592
10555.2.5.160/3055.2.5.161 to 55.2.5.16255.2.5.1632
10655.2.5.164/3055.2.5.165 to 55.2.5.16655.2.5.1672
10755.2.5.168/3055.2.5.169 to 55.2.5.17055.2.5.1712
10855.2.5.172/3055.2.5.173 to 55.2.5.17455.2.5.1752
10955.2.5.176/3055.2.5.177 to 55.2.5.17855.2.5.1792
11055.2.5.180/3055.2.5.181 to 55.2.5.18255.2.5.1832
11155.2.5.184/3055.2.5.185 to 55.2.5.18655.2.5.1872
11255.2.5.188/3055.2.5.189 to 55.2.5.19055.2.5.1912
11355.2.5.192/3055.2.5.193 to 55.2.5.19455.2.5.1952
11455.2.5.196/3055.2.5.197 to 55.2.5.19855.2.5.1992
11555.2.5.200/3055.2.5.201 to 55.2.5.20255.2.5.2032
11655.2.5.204/3055.2.5.205 to 55.2.5.20655.2.5.2072
11755.2.5.208/3055.2.5.209 to 55.2.5.21055.2.5.2112
11855.2.5.212/3055.2.5.213 to 55.2.5.21455.2.5.2152
11955.2.5.216/3055.2.5.217 to 55.2.5.21855.2.5.2192
12055.2.5.220/3055.2.5.221 to 55.2.5.22255.2.5.2232
12155.2.5.224/3055.2.5.225 to 55.2.5.22655.2.5.2272
12255.2.5.228/3055.2.5.229 to 55.2.5.23055.2.5.2312
12355.2.5.232/3055.2.5.233 to 55.2.5.23455.2.5.2352
12455.2.5.236/3055.2.5.237 to 55.2.5.23855.2.5.2392
12555.2.5.240/3055.2.5.241 to 55.2.5.24255.2.5.2432
12655.2.5.244/3055.2.5.245 to 55.2.5.24655.2.5.2472
12755.2.5.248/3055.2.5.249 to 55.2.5.25055.2.5.2512
12855.2.5.252/3055.2.5.253 to 55.2.5.25455.2.5.2552
12955.2.6.0/3055.2.6.1 to 55.2.6.255.2.6.32
13055.2.6.4/3055.2.6.5 to 55.2.6.655.2.6.72
13155.2.6.8/3055.2.6.9 to 55.2.6.1055.2.6.112
13255.2.6.12/3055.2.6.13 to 55.2.6.1455.2.6.152
13355.2.6.16/3055.2.6.17 to 55.2.6.1855.2.6.192
13455.2.6.20/3055.2.6.21 to 55.2.6.2255.2.6.232
13555.2.6.24/3055.2.6.25 to 55.2.6.2655.2.6.272
13655.2.6.28/3055.2.6.29 to 55.2.6.3055.2.6.312
13755.2.6.32/3055.2.6.33 to 55.2.6.3455.2.6.352
13855.2.6.36/3055.2.6.37 to 55.2.6.3855.2.6.392
13955.2.6.40/3055.2.6.41 to 55.2.6.4255.2.6.432
14055.2.6.44/3055.2.6.45 to 55.2.6.4655.2.6.472
14155.2.6.48/3055.2.6.49 to 55.2.6.5055.2.6.512
14255.2.6.52/3055.2.6.53 to 55.2.6.5455.2.6.552
14355.2.6.56/3055.2.6.57 to 55.2.6.5855.2.6.592
14455.2.6.60/3055.2.6.61 to 55.2.6.6255.2.6.632
14555.2.6.64/3055.2.6.65 to 55.2.6.6655.2.6.672
14655.2.6.68/3055.2.6.69 to 55.2.6.7055.2.6.712
14755.2.6.72/3055.2.6.73 to 55.2.6.7455.2.6.752
14855.2.6.76/3055.2.6.77 to 55.2.6.7855.2.6.792
14955.2.6.80/3055.2.6.81 to 55.2.6.8255.2.6.832
15055.2.6.84/3055.2.6.85 to 55.2.6.8655.2.6.872
15155.2.6.88/3055.2.6.89 to 55.2.6.9055.2.6.912
15255.2.6.92/3055.2.6.93 to 55.2.6.9455.2.6.952
15355.2.6.96/3055.2.6.97 to 55.2.6.9855.2.6.992
15455.2.6.100/3055.2.6.101 to 55.2.6.10255.2.6.1032
15555.2.6.104/3055.2.6.105 to 55.2.6.10655.2.6.1072
15655.2.6.108/3055.2.6.109 to 55.2.6.11055.2.6.1112
15755.2.6.112/3055.2.6.113 to 55.2.6.11455.2.6.1152
15855.2.6.116/3055.2.6.117 to 55.2.6.11855.2.6.1192
15955.2.6.120/3055.2.6.121 to 55.2.6.12255.2.6.1232
16055.2.6.124/3055.2.6.125 to 55.2.6.12655.2.6.1272
16155.2.6.128/3055.2.6.129 to 55.2.6.13055.2.6.1312
16255.2.6.132/3055.2.6.133 to 55.2.6.13455.2.6.1352
16355.2.6.136/3055.2.6.137 to 55.2.6.13855.2.6.1392
16455.2.6.140/3055.2.6.141 to 55.2.6.14255.2.6.1432
16555.2.6.144/3055.2.6.145 to 55.2.6.14655.2.6.1472
16655.2.6.148/3055.2.6.149 to 55.2.6.15055.2.6.1512
16755.2.6.152/3055.2.6.153 to 55.2.6.15455.2.6.1552
16855.2.6.156/3055.2.6.157 to 55.2.6.15855.2.6.1592
16955.2.6.160/3055.2.6.161 to 55.2.6.16255.2.6.1632
17055.2.6.164/3055.2.6.165 to 55.2.6.16655.2.6.1672
17155.2.6.168/3055.2.6.169 to 55.2.6.17055.2.6.1712
17255.2.6.172/3055.2.6.173 to 55.2.6.17455.2.6.1752
17355.2.6.176/3055.2.6.177 to 55.2.6.17855.2.6.1792
17455.2.6.180/3055.2.6.181 to 55.2.6.18255.2.6.1832
17555.2.6.184/3055.2.6.185 to 55.2.6.18655.2.6.1872
17655.2.6.188/3055.2.6.189 to 55.2.6.19055.2.6.1912
17755.2.6.192/3055.2.6.193 to 55.2.6.19455.2.6.1952
17855.2.6.196/3055.2.6.197 to 55.2.6.19855.2.6.1992
17955.2.6.200/3055.2.6.201 to 55.2.6.20255.2.6.2032
18055.2.6.204/3055.2.6.205 to 55.2.6.20655.2.6.2072
18155.2.6.208/3055.2.6.209 to 55.2.6.21055.2.6.2112
18255.2.6.212/3055.2.6.213 to 55.2.6.21455.2.6.2152
18355.2.6.216/3055.2.6.217 to 55.2.6.21855.2.6.2192
18455.2.6.220/3055.2.6.221 to 55.2.6.22255.2.6.2232
18555.2.6.224/3055.2.6.225 to 55.2.6.22655.2.6.2272
18655.2.6.228/3055.2.6.229 to 55.2.6.23055.2.6.2312
18755.2.6.232/3055.2.6.233 to 55.2.6.23455.2.6.2352
18855.2.6.236/3055.2.6.237 to 55.2.6.23855.2.6.2392
18955.2.6.240/3055.2.6.241 to 55.2.6.24255.2.6.2432
19055.2.6.244/3055.2.6.245 to 55.2.6.24655.2.6.2472
19155.2.6.248/3055.2.6.249 to 55.2.6.25055.2.6.2512
19255.2.6.252/3055.2.6.253 to 55.2.6.25455.2.6.2552
19355.2.7.0/3055.2.7.1 to 55.2.7.255.2.7.32
19455.2.7.4/3055.2.7.5 to 55.2.7.655.2.7.72
19555.2.7.8/3055.2.7.9 to 55.2.7.1055.2.7.112
19655.2.7.12/3055.2.7.13 to 55.2.7.1455.2.7.152
19755.2.7.16/3055.2.7.17 to 55.2.7.1855.2.7.192
19855.2.7.20/3055.2.7.21 to 55.2.7.2255.2.7.232
19955.2.7.24/3055.2.7.25 to 55.2.7.2655.2.7.272
20055.2.7.28/3055.2.7.29 to 55.2.7.3055.2.7.312
20155.2.7.32/3055.2.7.33 to 55.2.7.3455.2.7.352
20255.2.7.36/3055.2.7.37 to 55.2.7.3855.2.7.392
20355.2.7.40/3055.2.7.41 to 55.2.7.4255.2.7.432
20455.2.7.44/3055.2.7.45 to 55.2.7.4655.2.7.472
20555.2.7.48/3055.2.7.49 to 55.2.7.5055.2.7.512
20655.2.7.52/3055.2.7.53 to 55.2.7.5455.2.7.552
20755.2.7.56/3055.2.7.57 to 55.2.7.5855.2.7.592
20855.2.7.60/3055.2.7.61 to 55.2.7.6255.2.7.632
20955.2.7.64/3055.2.7.65 to 55.2.7.6655.2.7.672
21055.2.7.68/3055.2.7.69 to 55.2.7.7055.2.7.712
21155.2.7.72/3055.2.7.73 to 55.2.7.7455.2.7.752
21255.2.7.76/3055.2.7.77 to 55.2.7.7855.2.7.792
21355.2.7.80/3055.2.7.81 to 55.2.7.8255.2.7.832
21455.2.7.84/3055.2.7.85 to 55.2.7.8655.2.7.872
21555.2.7.88/3055.2.7.89 to 55.2.7.9055.2.7.912
21655.2.7.92/3055.2.7.93 to 55.2.7.9455.2.7.952
21755.2.7.96/3055.2.7.97 to 55.2.7.9855.2.7.992
21855.2.7.100/3055.2.7.101 to 55.2.7.10255.2.7.1032
21955.2.7.104/3055.2.7.105 to 55.2.7.10655.2.7.1072
22055.2.7.108/3055.2.7.109 to 55.2.7.11055.2.7.1112
22155.2.7.112/3055.2.7.113 to 55.2.7.11455.2.7.1152
22255.2.7.116/3055.2.7.117 to 55.2.7.11855.2.7.1192
22355.2.7.120/3055.2.7.121 to 55.2.7.12255.2.7.1232
22455.2.7.124/3055.2.7.125 to 55.2.7.12655.2.7.1272
22555.2.7.128/3055.2.7.129 to 55.2.7.13055.2.7.1312
22655.2.7.132/3055.2.7.133 to 55.2.7.13455.2.7.1352
22755.2.7.136/3055.2.7.137 to 55.2.7.13855.2.7.1392
22855.2.7.140/3055.2.7.141 to 55.2.7.14255.2.7.1432
22955.2.7.144/3055.2.7.145 to 55.2.7.14655.2.7.1472
23055.2.7.148/3055.2.7.149 to 55.2.7.15055.2.7.1512
23155.2.7.152/3055.2.7.153 to 55.2.7.15455.2.7.1552
23255.2.7.156/3055.2.7.157 to 55.2.7.15855.2.7.1592
23355.2.7.160/3055.2.7.161 to 55.2.7.16255.2.7.1632
23455.2.7.164/3055.2.7.165 to 55.2.7.16655.2.7.1672
23555.2.7.168/3055.2.7.169 to 55.2.7.17055.2.7.1712
23655.2.7.172/3055.2.7.173 to 55.2.7.17455.2.7.1752
23755.2.7.176/3055.2.7.177 to 55.2.7.17855.2.7.1792
23855.2.7.180/3055.2.7.181 to 55.2.7.18255.2.7.1832
23955.2.7.184/3055.2.7.185 to 55.2.7.18655.2.7.1872
24055.2.7.188/3055.2.7.189 to 55.2.7.19055.2.7.1912
24155.2.7.192/3055.2.7.193 to 55.2.7.19455.2.7.1952
24255.2.7.196/3055.2.7.197 to 55.2.7.19855.2.7.1992
24355.2.7.200/3055.2.7.201 to 55.2.7.20255.2.7.2032
24455.2.7.204/3055.2.7.205 to 55.2.7.20655.2.7.2072
24555.2.7.208/3055.2.7.209 to 55.2.7.21055.2.7.2112
24655.2.7.212/3055.2.7.213 to 55.2.7.21455.2.7.2152
24755.2.7.216/3055.2.7.217 to 55.2.7.21855.2.7.2192
24855.2.7.220/3055.2.7.221 to 55.2.7.22255.2.7.2232
24955.2.7.224/3055.2.7.225 to 55.2.7.22655.2.7.2272
25055.2.7.228/3055.2.7.229 to 55.2.7.23055.2.7.2312
25155.2.7.232/3055.2.7.233 to 55.2.7.23455.2.7.2352
25255.2.7.236/3055.2.7.237 to 55.2.7.23855.2.7.2392
25355.2.7.240/3055.2.7.241 to 55.2.7.24255.2.7.2432
25455.2.7.244/3055.2.7.245 to 55.2.7.24655.2.7.2472
25555.2.7.248/3055.2.7.249 to 55.2.7.25055.2.7.2512
25655.2.7.252/3055.2.7.253 to 55.2.7.25455.2.7.2552

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