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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.

Network41.3.232.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
41.3.232.0
Broadcast address
41.3.235.255
First usable
41.3.232.1
Last usable
41.3.235.254
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 2903E800 · Integer 688121856 to 688122879
Reverse DNS zones
232.3.41.in-addr.arpa
233.3.41.in-addr.arpa
234.3.41.in-addr.arpa
235.3.41.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
Address00101001.00000011.11101000.0000000041.3.232.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00101001.00000011.11101000.0000000041.3.232.0
Broadcast00101001.00000011.11101011.1111111141.3.235.255
Split into smaller subnets/30
/23 (2)/24 (4)/25 (8)/26 (16)/27 (32)/28 (64)/29 (128)/30 (256)/31 (512)/32 (1,024)

41.3.232.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
141.3.232.0/3041.3.232.1 to 41.3.232.241.3.232.32
241.3.232.4/3041.3.232.5 to 41.3.232.641.3.232.72
341.3.232.8/3041.3.232.9 to 41.3.232.1041.3.232.112
441.3.232.12/3041.3.232.13 to 41.3.232.1441.3.232.152
541.3.232.16/3041.3.232.17 to 41.3.232.1841.3.232.192
641.3.232.20/3041.3.232.21 to 41.3.232.2241.3.232.232
741.3.232.24/3041.3.232.25 to 41.3.232.2641.3.232.272
841.3.232.28/3041.3.232.29 to 41.3.232.3041.3.232.312
941.3.232.32/3041.3.232.33 to 41.3.232.3441.3.232.352
1041.3.232.36/3041.3.232.37 to 41.3.232.3841.3.232.392
1141.3.232.40/3041.3.232.41 to 41.3.232.4241.3.232.432
1241.3.232.44/3041.3.232.45 to 41.3.232.4641.3.232.472
1341.3.232.48/3041.3.232.49 to 41.3.232.5041.3.232.512
1441.3.232.52/3041.3.232.53 to 41.3.232.5441.3.232.552
1541.3.232.56/3041.3.232.57 to 41.3.232.5841.3.232.592
1641.3.232.60/3041.3.232.61 to 41.3.232.6241.3.232.632
1741.3.232.64/3041.3.232.65 to 41.3.232.6641.3.232.672
1841.3.232.68/3041.3.232.69 to 41.3.232.7041.3.232.712
1941.3.232.72/3041.3.232.73 to 41.3.232.7441.3.232.752
2041.3.232.76/3041.3.232.77 to 41.3.232.7841.3.232.792
2141.3.232.80/3041.3.232.81 to 41.3.232.8241.3.232.832
2241.3.232.84/3041.3.232.85 to 41.3.232.8641.3.232.872
2341.3.232.88/3041.3.232.89 to 41.3.232.9041.3.232.912
2441.3.232.92/3041.3.232.93 to 41.3.232.9441.3.232.952
2541.3.232.96/3041.3.232.97 to 41.3.232.9841.3.232.992
2641.3.232.100/3041.3.232.101 to 41.3.232.10241.3.232.1032
2741.3.232.104/3041.3.232.105 to 41.3.232.10641.3.232.1072
2841.3.232.108/3041.3.232.109 to 41.3.232.11041.3.232.1112
2941.3.232.112/3041.3.232.113 to 41.3.232.11441.3.232.1152
3041.3.232.116/3041.3.232.117 to 41.3.232.11841.3.232.1192
3141.3.232.120/3041.3.232.121 to 41.3.232.12241.3.232.1232
3241.3.232.124/3041.3.232.125 to 41.3.232.12641.3.232.1272
3341.3.232.128/3041.3.232.129 to 41.3.232.13041.3.232.1312
3441.3.232.132/3041.3.232.133 to 41.3.232.13441.3.232.1352
3541.3.232.136/3041.3.232.137 to 41.3.232.13841.3.232.1392
3641.3.232.140/3041.3.232.141 to 41.3.232.14241.3.232.1432
3741.3.232.144/3041.3.232.145 to 41.3.232.14641.3.232.1472
3841.3.232.148/3041.3.232.149 to 41.3.232.15041.3.232.1512
3941.3.232.152/3041.3.232.153 to 41.3.232.15441.3.232.1552
4041.3.232.156/3041.3.232.157 to 41.3.232.15841.3.232.1592
4141.3.232.160/3041.3.232.161 to 41.3.232.16241.3.232.1632
4241.3.232.164/3041.3.232.165 to 41.3.232.16641.3.232.1672
4341.3.232.168/3041.3.232.169 to 41.3.232.17041.3.232.1712
4441.3.232.172/3041.3.232.173 to 41.3.232.17441.3.232.1752
4541.3.232.176/3041.3.232.177 to 41.3.232.17841.3.232.1792
4641.3.232.180/3041.3.232.181 to 41.3.232.18241.3.232.1832
4741.3.232.184/3041.3.232.185 to 41.3.232.18641.3.232.1872
4841.3.232.188/3041.3.232.189 to 41.3.232.19041.3.232.1912
4941.3.232.192/3041.3.232.193 to 41.3.232.19441.3.232.1952
5041.3.232.196/3041.3.232.197 to 41.3.232.19841.3.232.1992
5141.3.232.200/3041.3.232.201 to 41.3.232.20241.3.232.2032
5241.3.232.204/3041.3.232.205 to 41.3.232.20641.3.232.2072
5341.3.232.208/3041.3.232.209 to 41.3.232.21041.3.232.2112
5441.3.232.212/3041.3.232.213 to 41.3.232.21441.3.232.2152
5541.3.232.216/3041.3.232.217 to 41.3.232.21841.3.232.2192
5641.3.232.220/3041.3.232.221 to 41.3.232.22241.3.232.2232
5741.3.232.224/3041.3.232.225 to 41.3.232.22641.3.232.2272
5841.3.232.228/3041.3.232.229 to 41.3.232.23041.3.232.2312
5941.3.232.232/3041.3.232.233 to 41.3.232.23441.3.232.2352
6041.3.232.236/3041.3.232.237 to 41.3.232.23841.3.232.2392
6141.3.232.240/3041.3.232.241 to 41.3.232.24241.3.232.2432
6241.3.232.244/3041.3.232.245 to 41.3.232.24641.3.232.2472
6341.3.232.248/3041.3.232.249 to 41.3.232.25041.3.232.2512
6441.3.232.252/3041.3.232.253 to 41.3.232.25441.3.232.2552
6541.3.233.0/3041.3.233.1 to 41.3.233.241.3.233.32
6641.3.233.4/3041.3.233.5 to 41.3.233.641.3.233.72
6741.3.233.8/3041.3.233.9 to 41.3.233.1041.3.233.112
6841.3.233.12/3041.3.233.13 to 41.3.233.1441.3.233.152
6941.3.233.16/3041.3.233.17 to 41.3.233.1841.3.233.192
7041.3.233.20/3041.3.233.21 to 41.3.233.2241.3.233.232
7141.3.233.24/3041.3.233.25 to 41.3.233.2641.3.233.272
7241.3.233.28/3041.3.233.29 to 41.3.233.3041.3.233.312
7341.3.233.32/3041.3.233.33 to 41.3.233.3441.3.233.352
7441.3.233.36/3041.3.233.37 to 41.3.233.3841.3.233.392
7541.3.233.40/3041.3.233.41 to 41.3.233.4241.3.233.432
7641.3.233.44/3041.3.233.45 to 41.3.233.4641.3.233.472
7741.3.233.48/3041.3.233.49 to 41.3.233.5041.3.233.512
7841.3.233.52/3041.3.233.53 to 41.3.233.5441.3.233.552
7941.3.233.56/3041.3.233.57 to 41.3.233.5841.3.233.592
8041.3.233.60/3041.3.233.61 to 41.3.233.6241.3.233.632
8141.3.233.64/3041.3.233.65 to 41.3.233.6641.3.233.672
8241.3.233.68/3041.3.233.69 to 41.3.233.7041.3.233.712
8341.3.233.72/3041.3.233.73 to 41.3.233.7441.3.233.752
8441.3.233.76/3041.3.233.77 to 41.3.233.7841.3.233.792
8541.3.233.80/3041.3.233.81 to 41.3.233.8241.3.233.832
8641.3.233.84/3041.3.233.85 to 41.3.233.8641.3.233.872
8741.3.233.88/3041.3.233.89 to 41.3.233.9041.3.233.912
8841.3.233.92/3041.3.233.93 to 41.3.233.9441.3.233.952
8941.3.233.96/3041.3.233.97 to 41.3.233.9841.3.233.992
9041.3.233.100/3041.3.233.101 to 41.3.233.10241.3.233.1032
9141.3.233.104/3041.3.233.105 to 41.3.233.10641.3.233.1072
9241.3.233.108/3041.3.233.109 to 41.3.233.11041.3.233.1112
9341.3.233.112/3041.3.233.113 to 41.3.233.11441.3.233.1152
9441.3.233.116/3041.3.233.117 to 41.3.233.11841.3.233.1192
9541.3.233.120/3041.3.233.121 to 41.3.233.12241.3.233.1232
9641.3.233.124/3041.3.233.125 to 41.3.233.12641.3.233.1272
9741.3.233.128/3041.3.233.129 to 41.3.233.13041.3.233.1312
9841.3.233.132/3041.3.233.133 to 41.3.233.13441.3.233.1352
9941.3.233.136/3041.3.233.137 to 41.3.233.13841.3.233.1392
10041.3.233.140/3041.3.233.141 to 41.3.233.14241.3.233.1432
10141.3.233.144/3041.3.233.145 to 41.3.233.14641.3.233.1472
10241.3.233.148/3041.3.233.149 to 41.3.233.15041.3.233.1512
10341.3.233.152/3041.3.233.153 to 41.3.233.15441.3.233.1552
10441.3.233.156/3041.3.233.157 to 41.3.233.15841.3.233.1592
10541.3.233.160/3041.3.233.161 to 41.3.233.16241.3.233.1632
10641.3.233.164/3041.3.233.165 to 41.3.233.16641.3.233.1672
10741.3.233.168/3041.3.233.169 to 41.3.233.17041.3.233.1712
10841.3.233.172/3041.3.233.173 to 41.3.233.17441.3.233.1752
10941.3.233.176/3041.3.233.177 to 41.3.233.17841.3.233.1792
11041.3.233.180/3041.3.233.181 to 41.3.233.18241.3.233.1832
11141.3.233.184/3041.3.233.185 to 41.3.233.18641.3.233.1872
11241.3.233.188/3041.3.233.189 to 41.3.233.19041.3.233.1912
11341.3.233.192/3041.3.233.193 to 41.3.233.19441.3.233.1952
11441.3.233.196/3041.3.233.197 to 41.3.233.19841.3.233.1992
11541.3.233.200/3041.3.233.201 to 41.3.233.20241.3.233.2032
11641.3.233.204/3041.3.233.205 to 41.3.233.20641.3.233.2072
11741.3.233.208/3041.3.233.209 to 41.3.233.21041.3.233.2112
11841.3.233.212/3041.3.233.213 to 41.3.233.21441.3.233.2152
11941.3.233.216/3041.3.233.217 to 41.3.233.21841.3.233.2192
12041.3.233.220/3041.3.233.221 to 41.3.233.22241.3.233.2232
12141.3.233.224/3041.3.233.225 to 41.3.233.22641.3.233.2272
12241.3.233.228/3041.3.233.229 to 41.3.233.23041.3.233.2312
12341.3.233.232/3041.3.233.233 to 41.3.233.23441.3.233.2352
12441.3.233.236/3041.3.233.237 to 41.3.233.23841.3.233.2392
12541.3.233.240/3041.3.233.241 to 41.3.233.24241.3.233.2432
12641.3.233.244/3041.3.233.245 to 41.3.233.24641.3.233.2472
12741.3.233.248/3041.3.233.249 to 41.3.233.25041.3.233.2512
12841.3.233.252/3041.3.233.253 to 41.3.233.25441.3.233.2552
12941.3.234.0/3041.3.234.1 to 41.3.234.241.3.234.32
13041.3.234.4/3041.3.234.5 to 41.3.234.641.3.234.72
13141.3.234.8/3041.3.234.9 to 41.3.234.1041.3.234.112
13241.3.234.12/3041.3.234.13 to 41.3.234.1441.3.234.152
13341.3.234.16/3041.3.234.17 to 41.3.234.1841.3.234.192
13441.3.234.20/3041.3.234.21 to 41.3.234.2241.3.234.232
13541.3.234.24/3041.3.234.25 to 41.3.234.2641.3.234.272
13641.3.234.28/3041.3.234.29 to 41.3.234.3041.3.234.312
13741.3.234.32/3041.3.234.33 to 41.3.234.3441.3.234.352
13841.3.234.36/3041.3.234.37 to 41.3.234.3841.3.234.392
13941.3.234.40/3041.3.234.41 to 41.3.234.4241.3.234.432
14041.3.234.44/3041.3.234.45 to 41.3.234.4641.3.234.472
14141.3.234.48/3041.3.234.49 to 41.3.234.5041.3.234.512
14241.3.234.52/3041.3.234.53 to 41.3.234.5441.3.234.552
14341.3.234.56/3041.3.234.57 to 41.3.234.5841.3.234.592
14441.3.234.60/3041.3.234.61 to 41.3.234.6241.3.234.632
14541.3.234.64/3041.3.234.65 to 41.3.234.6641.3.234.672
14641.3.234.68/3041.3.234.69 to 41.3.234.7041.3.234.712
14741.3.234.72/3041.3.234.73 to 41.3.234.7441.3.234.752
14841.3.234.76/3041.3.234.77 to 41.3.234.7841.3.234.792
14941.3.234.80/3041.3.234.81 to 41.3.234.8241.3.234.832
15041.3.234.84/3041.3.234.85 to 41.3.234.8641.3.234.872
15141.3.234.88/3041.3.234.89 to 41.3.234.9041.3.234.912
15241.3.234.92/3041.3.234.93 to 41.3.234.9441.3.234.952
15341.3.234.96/3041.3.234.97 to 41.3.234.9841.3.234.992
15441.3.234.100/3041.3.234.101 to 41.3.234.10241.3.234.1032
15541.3.234.104/3041.3.234.105 to 41.3.234.10641.3.234.1072
15641.3.234.108/3041.3.234.109 to 41.3.234.11041.3.234.1112
15741.3.234.112/3041.3.234.113 to 41.3.234.11441.3.234.1152
15841.3.234.116/3041.3.234.117 to 41.3.234.11841.3.234.1192
15941.3.234.120/3041.3.234.121 to 41.3.234.12241.3.234.1232
16041.3.234.124/3041.3.234.125 to 41.3.234.12641.3.234.1272
16141.3.234.128/3041.3.234.129 to 41.3.234.13041.3.234.1312
16241.3.234.132/3041.3.234.133 to 41.3.234.13441.3.234.1352
16341.3.234.136/3041.3.234.137 to 41.3.234.13841.3.234.1392
16441.3.234.140/3041.3.234.141 to 41.3.234.14241.3.234.1432
16541.3.234.144/3041.3.234.145 to 41.3.234.14641.3.234.1472
16641.3.234.148/3041.3.234.149 to 41.3.234.15041.3.234.1512
16741.3.234.152/3041.3.234.153 to 41.3.234.15441.3.234.1552
16841.3.234.156/3041.3.234.157 to 41.3.234.15841.3.234.1592
16941.3.234.160/3041.3.234.161 to 41.3.234.16241.3.234.1632
17041.3.234.164/3041.3.234.165 to 41.3.234.16641.3.234.1672
17141.3.234.168/3041.3.234.169 to 41.3.234.17041.3.234.1712
17241.3.234.172/3041.3.234.173 to 41.3.234.17441.3.234.1752
17341.3.234.176/3041.3.234.177 to 41.3.234.17841.3.234.1792
17441.3.234.180/3041.3.234.181 to 41.3.234.18241.3.234.1832
17541.3.234.184/3041.3.234.185 to 41.3.234.18641.3.234.1872
17641.3.234.188/3041.3.234.189 to 41.3.234.19041.3.234.1912
17741.3.234.192/3041.3.234.193 to 41.3.234.19441.3.234.1952
17841.3.234.196/3041.3.234.197 to 41.3.234.19841.3.234.1992
17941.3.234.200/3041.3.234.201 to 41.3.234.20241.3.234.2032
18041.3.234.204/3041.3.234.205 to 41.3.234.20641.3.234.2072
18141.3.234.208/3041.3.234.209 to 41.3.234.21041.3.234.2112
18241.3.234.212/3041.3.234.213 to 41.3.234.21441.3.234.2152
18341.3.234.216/3041.3.234.217 to 41.3.234.21841.3.234.2192
18441.3.234.220/3041.3.234.221 to 41.3.234.22241.3.234.2232
18541.3.234.224/3041.3.234.225 to 41.3.234.22641.3.234.2272
18641.3.234.228/3041.3.234.229 to 41.3.234.23041.3.234.2312
18741.3.234.232/3041.3.234.233 to 41.3.234.23441.3.234.2352
18841.3.234.236/3041.3.234.237 to 41.3.234.23841.3.234.2392
18941.3.234.240/3041.3.234.241 to 41.3.234.24241.3.234.2432
19041.3.234.244/3041.3.234.245 to 41.3.234.24641.3.234.2472
19141.3.234.248/3041.3.234.249 to 41.3.234.25041.3.234.2512
19241.3.234.252/3041.3.234.253 to 41.3.234.25441.3.234.2552
19341.3.235.0/3041.3.235.1 to 41.3.235.241.3.235.32
19441.3.235.4/3041.3.235.5 to 41.3.235.641.3.235.72
19541.3.235.8/3041.3.235.9 to 41.3.235.1041.3.235.112
19641.3.235.12/3041.3.235.13 to 41.3.235.1441.3.235.152
19741.3.235.16/3041.3.235.17 to 41.3.235.1841.3.235.192
19841.3.235.20/3041.3.235.21 to 41.3.235.2241.3.235.232
19941.3.235.24/3041.3.235.25 to 41.3.235.2641.3.235.272
20041.3.235.28/3041.3.235.29 to 41.3.235.3041.3.235.312
20141.3.235.32/3041.3.235.33 to 41.3.235.3441.3.235.352
20241.3.235.36/3041.3.235.37 to 41.3.235.3841.3.235.392
20341.3.235.40/3041.3.235.41 to 41.3.235.4241.3.235.432
20441.3.235.44/3041.3.235.45 to 41.3.235.4641.3.235.472
20541.3.235.48/3041.3.235.49 to 41.3.235.5041.3.235.512
20641.3.235.52/3041.3.235.53 to 41.3.235.5441.3.235.552
20741.3.235.56/3041.3.235.57 to 41.3.235.5841.3.235.592
20841.3.235.60/3041.3.235.61 to 41.3.235.6241.3.235.632
20941.3.235.64/3041.3.235.65 to 41.3.235.6641.3.235.672
21041.3.235.68/3041.3.235.69 to 41.3.235.7041.3.235.712
21141.3.235.72/3041.3.235.73 to 41.3.235.7441.3.235.752
21241.3.235.76/3041.3.235.77 to 41.3.235.7841.3.235.792
21341.3.235.80/3041.3.235.81 to 41.3.235.8241.3.235.832
21441.3.235.84/3041.3.235.85 to 41.3.235.8641.3.235.872
21541.3.235.88/3041.3.235.89 to 41.3.235.9041.3.235.912
21641.3.235.92/3041.3.235.93 to 41.3.235.9441.3.235.952
21741.3.235.96/3041.3.235.97 to 41.3.235.9841.3.235.992
21841.3.235.100/3041.3.235.101 to 41.3.235.10241.3.235.1032
21941.3.235.104/3041.3.235.105 to 41.3.235.10641.3.235.1072
22041.3.235.108/3041.3.235.109 to 41.3.235.11041.3.235.1112
22141.3.235.112/3041.3.235.113 to 41.3.235.11441.3.235.1152
22241.3.235.116/3041.3.235.117 to 41.3.235.11841.3.235.1192
22341.3.235.120/3041.3.235.121 to 41.3.235.12241.3.235.1232
22441.3.235.124/3041.3.235.125 to 41.3.235.12641.3.235.1272
22541.3.235.128/3041.3.235.129 to 41.3.235.13041.3.235.1312
22641.3.235.132/3041.3.235.133 to 41.3.235.13441.3.235.1352
22741.3.235.136/3041.3.235.137 to 41.3.235.13841.3.235.1392
22841.3.235.140/3041.3.235.141 to 41.3.235.14241.3.235.1432
22941.3.235.144/3041.3.235.145 to 41.3.235.14641.3.235.1472
23041.3.235.148/3041.3.235.149 to 41.3.235.15041.3.235.1512
23141.3.235.152/3041.3.235.153 to 41.3.235.15441.3.235.1552
23241.3.235.156/3041.3.235.157 to 41.3.235.15841.3.235.1592
23341.3.235.160/3041.3.235.161 to 41.3.235.16241.3.235.1632
23441.3.235.164/3041.3.235.165 to 41.3.235.16641.3.235.1672
23541.3.235.168/3041.3.235.169 to 41.3.235.17041.3.235.1712
23641.3.235.172/3041.3.235.173 to 41.3.235.17441.3.235.1752
23741.3.235.176/3041.3.235.177 to 41.3.235.17841.3.235.1792
23841.3.235.180/3041.3.235.181 to 41.3.235.18241.3.235.1832
23941.3.235.184/3041.3.235.185 to 41.3.235.18641.3.235.1872
24041.3.235.188/3041.3.235.189 to 41.3.235.19041.3.235.1912
24141.3.235.192/3041.3.235.193 to 41.3.235.19441.3.235.1952
24241.3.235.196/3041.3.235.197 to 41.3.235.19841.3.235.1992
24341.3.235.200/3041.3.235.201 to 41.3.235.20241.3.235.2032
24441.3.235.204/3041.3.235.205 to 41.3.235.20641.3.235.2072
24541.3.235.208/3041.3.235.209 to 41.3.235.21041.3.235.2112
24641.3.235.212/3041.3.235.213 to 41.3.235.21441.3.235.2152
24741.3.235.216/3041.3.235.217 to 41.3.235.21841.3.235.2192
24841.3.235.220/3041.3.235.221 to 41.3.235.22241.3.235.2232
24941.3.235.224/3041.3.235.225 to 41.3.235.22641.3.235.2272
25041.3.235.228/3041.3.235.229 to 41.3.235.23041.3.235.2312
25141.3.235.232/3041.3.235.233 to 41.3.235.23441.3.235.2352
25241.3.235.236/3041.3.235.237 to 41.3.235.23841.3.235.2392
25341.3.235.240/3041.3.235.241 to 41.3.235.24241.3.235.2432
25441.3.235.244/3041.3.235.245 to 41.3.235.24641.3.235.2472
25541.3.235.248/3041.3.235.249 to 41.3.235.25041.3.235.2512
25641.3.235.252/3041.3.235.253 to 41.3.235.25441.3.235.2552

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

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.