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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.

Network92.63.0.0/18
Usable hosts16,382
Subnet mask255.255.192.0
Addresses16,384
Network address
92.63.0.0
Broadcast address
92.63.63.255
First usable
92.63.0.1
Last usable
92.63.63.254
Usable hosts
16,382 (16,384 less the network and broadcast addresses)
Subnet mask
255.255.192.0
Wildcard mask
0.0.63.255 (Cisco ACLs, OSPF)
Prefix length
/18
Type
Public public
Old class
A (default /8)
As numbers
Hex 5C3F0000 · Integer 1547632640 to 1547649023
Reverse DNS zones
0.63.92.in-addr.arpa
1.63.92.in-addr.arpa
2.63.92.in-addr.arpa
3.63.92.in-addr.arpa
4.63.92.in-addr.arpa
5.63.92.in-addr.arpa
6.63.92.in-addr.arpa
7.63.92.in-addr.arpa
8.63.92.in-addr.arpa
9.63.92.in-addr.arpa
10.63.92.in-addr.arpa
11.63.92.in-addr.arpa
12.63.92.in-addr.arpa
13.63.92.in-addr.arpa
14.63.92.in-addr.arpa
15.63.92.in-addr.arpa
and 48 more
/18 is not on a 8-bit boundary, so it takes 64 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011100.00111111.00000000.0000000092.63.0.0
Subnet mask11111111.11111111.11000000.00000000255.255.192.0
Network01011100.00111111.00000000.0000000092.63.0.0
Broadcast01011100.00111111.00111111.1111111192.63.63.255
Split into smaller subnets/30
/19 (2)/20 (4)/21 (8)/22 (16)/23 (32)/24 (64)/25 (128)/26 (256)/27 (512)/28 (1,024)/29 (2,048)/30 (4,096)

92.63.0.0/18 makes 4,096 subnets of /30; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
192.63.0.0/3092.63.0.1 to 92.63.0.292.63.0.32
292.63.0.4/3092.63.0.5 to 92.63.0.692.63.0.72
392.63.0.8/3092.63.0.9 to 92.63.0.1092.63.0.112
492.63.0.12/3092.63.0.13 to 92.63.0.1492.63.0.152
592.63.0.16/3092.63.0.17 to 92.63.0.1892.63.0.192
692.63.0.20/3092.63.0.21 to 92.63.0.2292.63.0.232
792.63.0.24/3092.63.0.25 to 92.63.0.2692.63.0.272
892.63.0.28/3092.63.0.29 to 92.63.0.3092.63.0.312
992.63.0.32/3092.63.0.33 to 92.63.0.3492.63.0.352
1092.63.0.36/3092.63.0.37 to 92.63.0.3892.63.0.392
1192.63.0.40/3092.63.0.41 to 92.63.0.4292.63.0.432
1292.63.0.44/3092.63.0.45 to 92.63.0.4692.63.0.472
1392.63.0.48/3092.63.0.49 to 92.63.0.5092.63.0.512
1492.63.0.52/3092.63.0.53 to 92.63.0.5492.63.0.552
1592.63.0.56/3092.63.0.57 to 92.63.0.5892.63.0.592
1692.63.0.60/3092.63.0.61 to 92.63.0.6292.63.0.632
1792.63.0.64/3092.63.0.65 to 92.63.0.6692.63.0.672
1892.63.0.68/3092.63.0.69 to 92.63.0.7092.63.0.712
1992.63.0.72/3092.63.0.73 to 92.63.0.7492.63.0.752
2092.63.0.76/3092.63.0.77 to 92.63.0.7892.63.0.792
2192.63.0.80/3092.63.0.81 to 92.63.0.8292.63.0.832
2292.63.0.84/3092.63.0.85 to 92.63.0.8692.63.0.872
2392.63.0.88/3092.63.0.89 to 92.63.0.9092.63.0.912
2492.63.0.92/3092.63.0.93 to 92.63.0.9492.63.0.952
2592.63.0.96/3092.63.0.97 to 92.63.0.9892.63.0.992
2692.63.0.100/3092.63.0.101 to 92.63.0.10292.63.0.1032
2792.63.0.104/3092.63.0.105 to 92.63.0.10692.63.0.1072
2892.63.0.108/3092.63.0.109 to 92.63.0.11092.63.0.1112
2992.63.0.112/3092.63.0.113 to 92.63.0.11492.63.0.1152
3092.63.0.116/3092.63.0.117 to 92.63.0.11892.63.0.1192
3192.63.0.120/3092.63.0.121 to 92.63.0.12292.63.0.1232
3292.63.0.124/3092.63.0.125 to 92.63.0.12692.63.0.1272
3392.63.0.128/3092.63.0.129 to 92.63.0.13092.63.0.1312
3492.63.0.132/3092.63.0.133 to 92.63.0.13492.63.0.1352
3592.63.0.136/3092.63.0.137 to 92.63.0.13892.63.0.1392
3692.63.0.140/3092.63.0.141 to 92.63.0.14292.63.0.1432
3792.63.0.144/3092.63.0.145 to 92.63.0.14692.63.0.1472
3892.63.0.148/3092.63.0.149 to 92.63.0.15092.63.0.1512
3992.63.0.152/3092.63.0.153 to 92.63.0.15492.63.0.1552
4092.63.0.156/3092.63.0.157 to 92.63.0.15892.63.0.1592
4192.63.0.160/3092.63.0.161 to 92.63.0.16292.63.0.1632
4292.63.0.164/3092.63.0.165 to 92.63.0.16692.63.0.1672
4392.63.0.168/3092.63.0.169 to 92.63.0.17092.63.0.1712
4492.63.0.172/3092.63.0.173 to 92.63.0.17492.63.0.1752
4592.63.0.176/3092.63.0.177 to 92.63.0.17892.63.0.1792
4692.63.0.180/3092.63.0.181 to 92.63.0.18292.63.0.1832
4792.63.0.184/3092.63.0.185 to 92.63.0.18692.63.0.1872
4892.63.0.188/3092.63.0.189 to 92.63.0.19092.63.0.1912
4992.63.0.192/3092.63.0.193 to 92.63.0.19492.63.0.1952
5092.63.0.196/3092.63.0.197 to 92.63.0.19892.63.0.1992
5192.63.0.200/3092.63.0.201 to 92.63.0.20292.63.0.2032
5292.63.0.204/3092.63.0.205 to 92.63.0.20692.63.0.2072
5392.63.0.208/3092.63.0.209 to 92.63.0.21092.63.0.2112
5492.63.0.212/3092.63.0.213 to 92.63.0.21492.63.0.2152
5592.63.0.216/3092.63.0.217 to 92.63.0.21892.63.0.2192
5692.63.0.220/3092.63.0.221 to 92.63.0.22292.63.0.2232
5792.63.0.224/3092.63.0.225 to 92.63.0.22692.63.0.2272
5892.63.0.228/3092.63.0.229 to 92.63.0.23092.63.0.2312
5992.63.0.232/3092.63.0.233 to 92.63.0.23492.63.0.2352
6092.63.0.236/3092.63.0.237 to 92.63.0.23892.63.0.2392
6192.63.0.240/3092.63.0.241 to 92.63.0.24292.63.0.2432
6292.63.0.244/3092.63.0.245 to 92.63.0.24692.63.0.2472
6392.63.0.248/3092.63.0.249 to 92.63.0.25092.63.0.2512
6492.63.0.252/3092.63.0.253 to 92.63.0.25492.63.0.2552
6592.63.1.0/3092.63.1.1 to 92.63.1.292.63.1.32
6692.63.1.4/3092.63.1.5 to 92.63.1.692.63.1.72
6792.63.1.8/3092.63.1.9 to 92.63.1.1092.63.1.112
6892.63.1.12/3092.63.1.13 to 92.63.1.1492.63.1.152
6992.63.1.16/3092.63.1.17 to 92.63.1.1892.63.1.192
7092.63.1.20/3092.63.1.21 to 92.63.1.2292.63.1.232
7192.63.1.24/3092.63.1.25 to 92.63.1.2692.63.1.272
7292.63.1.28/3092.63.1.29 to 92.63.1.3092.63.1.312
7392.63.1.32/3092.63.1.33 to 92.63.1.3492.63.1.352
7492.63.1.36/3092.63.1.37 to 92.63.1.3892.63.1.392
7592.63.1.40/3092.63.1.41 to 92.63.1.4292.63.1.432
7692.63.1.44/3092.63.1.45 to 92.63.1.4692.63.1.472
7792.63.1.48/3092.63.1.49 to 92.63.1.5092.63.1.512
7892.63.1.52/3092.63.1.53 to 92.63.1.5492.63.1.552
7992.63.1.56/3092.63.1.57 to 92.63.1.5892.63.1.592
8092.63.1.60/3092.63.1.61 to 92.63.1.6292.63.1.632
8192.63.1.64/3092.63.1.65 to 92.63.1.6692.63.1.672
8292.63.1.68/3092.63.1.69 to 92.63.1.7092.63.1.712
8392.63.1.72/3092.63.1.73 to 92.63.1.7492.63.1.752
8492.63.1.76/3092.63.1.77 to 92.63.1.7892.63.1.792
8592.63.1.80/3092.63.1.81 to 92.63.1.8292.63.1.832
8692.63.1.84/3092.63.1.85 to 92.63.1.8692.63.1.872
8792.63.1.88/3092.63.1.89 to 92.63.1.9092.63.1.912
8892.63.1.92/3092.63.1.93 to 92.63.1.9492.63.1.952
8992.63.1.96/3092.63.1.97 to 92.63.1.9892.63.1.992
9092.63.1.100/3092.63.1.101 to 92.63.1.10292.63.1.1032
9192.63.1.104/3092.63.1.105 to 92.63.1.10692.63.1.1072
9292.63.1.108/3092.63.1.109 to 92.63.1.11092.63.1.1112
9392.63.1.112/3092.63.1.113 to 92.63.1.11492.63.1.1152
9492.63.1.116/3092.63.1.117 to 92.63.1.11892.63.1.1192
9592.63.1.120/3092.63.1.121 to 92.63.1.12292.63.1.1232
9692.63.1.124/3092.63.1.125 to 92.63.1.12692.63.1.1272
9792.63.1.128/3092.63.1.129 to 92.63.1.13092.63.1.1312
9892.63.1.132/3092.63.1.133 to 92.63.1.13492.63.1.1352
9992.63.1.136/3092.63.1.137 to 92.63.1.13892.63.1.1392
10092.63.1.140/3092.63.1.141 to 92.63.1.14292.63.1.1432
10192.63.1.144/3092.63.1.145 to 92.63.1.14692.63.1.1472
10292.63.1.148/3092.63.1.149 to 92.63.1.15092.63.1.1512
10392.63.1.152/3092.63.1.153 to 92.63.1.15492.63.1.1552
10492.63.1.156/3092.63.1.157 to 92.63.1.15892.63.1.1592
10592.63.1.160/3092.63.1.161 to 92.63.1.16292.63.1.1632
10692.63.1.164/3092.63.1.165 to 92.63.1.16692.63.1.1672
10792.63.1.168/3092.63.1.169 to 92.63.1.17092.63.1.1712
10892.63.1.172/3092.63.1.173 to 92.63.1.17492.63.1.1752
10992.63.1.176/3092.63.1.177 to 92.63.1.17892.63.1.1792
11092.63.1.180/3092.63.1.181 to 92.63.1.18292.63.1.1832
11192.63.1.184/3092.63.1.185 to 92.63.1.18692.63.1.1872
11292.63.1.188/3092.63.1.189 to 92.63.1.19092.63.1.1912
11392.63.1.192/3092.63.1.193 to 92.63.1.19492.63.1.1952
11492.63.1.196/3092.63.1.197 to 92.63.1.19892.63.1.1992
11592.63.1.200/3092.63.1.201 to 92.63.1.20292.63.1.2032
11692.63.1.204/3092.63.1.205 to 92.63.1.20692.63.1.2072
11792.63.1.208/3092.63.1.209 to 92.63.1.21092.63.1.2112
11892.63.1.212/3092.63.1.213 to 92.63.1.21492.63.1.2152
11992.63.1.216/3092.63.1.217 to 92.63.1.21892.63.1.2192
12092.63.1.220/3092.63.1.221 to 92.63.1.22292.63.1.2232
12192.63.1.224/3092.63.1.225 to 92.63.1.22692.63.1.2272
12292.63.1.228/3092.63.1.229 to 92.63.1.23092.63.1.2312
12392.63.1.232/3092.63.1.233 to 92.63.1.23492.63.1.2352
12492.63.1.236/3092.63.1.237 to 92.63.1.23892.63.1.2392
12592.63.1.240/3092.63.1.241 to 92.63.1.24292.63.1.2432
12692.63.1.244/3092.63.1.245 to 92.63.1.24692.63.1.2472
12792.63.1.248/3092.63.1.249 to 92.63.1.25092.63.1.2512
12892.63.1.252/3092.63.1.253 to 92.63.1.25492.63.1.2552
12992.63.2.0/3092.63.2.1 to 92.63.2.292.63.2.32
13092.63.2.4/3092.63.2.5 to 92.63.2.692.63.2.72
13192.63.2.8/3092.63.2.9 to 92.63.2.1092.63.2.112
13292.63.2.12/3092.63.2.13 to 92.63.2.1492.63.2.152
13392.63.2.16/3092.63.2.17 to 92.63.2.1892.63.2.192
13492.63.2.20/3092.63.2.21 to 92.63.2.2292.63.2.232
13592.63.2.24/3092.63.2.25 to 92.63.2.2692.63.2.272
13692.63.2.28/3092.63.2.29 to 92.63.2.3092.63.2.312
13792.63.2.32/3092.63.2.33 to 92.63.2.3492.63.2.352
13892.63.2.36/3092.63.2.37 to 92.63.2.3892.63.2.392
13992.63.2.40/3092.63.2.41 to 92.63.2.4292.63.2.432
14092.63.2.44/3092.63.2.45 to 92.63.2.4692.63.2.472
14192.63.2.48/3092.63.2.49 to 92.63.2.5092.63.2.512
14292.63.2.52/3092.63.2.53 to 92.63.2.5492.63.2.552
14392.63.2.56/3092.63.2.57 to 92.63.2.5892.63.2.592
14492.63.2.60/3092.63.2.61 to 92.63.2.6292.63.2.632
14592.63.2.64/3092.63.2.65 to 92.63.2.6692.63.2.672
14692.63.2.68/3092.63.2.69 to 92.63.2.7092.63.2.712
14792.63.2.72/3092.63.2.73 to 92.63.2.7492.63.2.752
14892.63.2.76/3092.63.2.77 to 92.63.2.7892.63.2.792
14992.63.2.80/3092.63.2.81 to 92.63.2.8292.63.2.832
15092.63.2.84/3092.63.2.85 to 92.63.2.8692.63.2.872
15192.63.2.88/3092.63.2.89 to 92.63.2.9092.63.2.912
15292.63.2.92/3092.63.2.93 to 92.63.2.9492.63.2.952
15392.63.2.96/3092.63.2.97 to 92.63.2.9892.63.2.992
15492.63.2.100/3092.63.2.101 to 92.63.2.10292.63.2.1032
15592.63.2.104/3092.63.2.105 to 92.63.2.10692.63.2.1072
15692.63.2.108/3092.63.2.109 to 92.63.2.11092.63.2.1112
15792.63.2.112/3092.63.2.113 to 92.63.2.11492.63.2.1152
15892.63.2.116/3092.63.2.117 to 92.63.2.11892.63.2.1192
15992.63.2.120/3092.63.2.121 to 92.63.2.12292.63.2.1232
16092.63.2.124/3092.63.2.125 to 92.63.2.12692.63.2.1272
16192.63.2.128/3092.63.2.129 to 92.63.2.13092.63.2.1312
16292.63.2.132/3092.63.2.133 to 92.63.2.13492.63.2.1352
16392.63.2.136/3092.63.2.137 to 92.63.2.13892.63.2.1392
16492.63.2.140/3092.63.2.141 to 92.63.2.14292.63.2.1432
16592.63.2.144/3092.63.2.145 to 92.63.2.14692.63.2.1472
16692.63.2.148/3092.63.2.149 to 92.63.2.15092.63.2.1512
16792.63.2.152/3092.63.2.153 to 92.63.2.15492.63.2.1552
16892.63.2.156/3092.63.2.157 to 92.63.2.15892.63.2.1592
16992.63.2.160/3092.63.2.161 to 92.63.2.16292.63.2.1632
17092.63.2.164/3092.63.2.165 to 92.63.2.16692.63.2.1672
17192.63.2.168/3092.63.2.169 to 92.63.2.17092.63.2.1712
17292.63.2.172/3092.63.2.173 to 92.63.2.17492.63.2.1752
17392.63.2.176/3092.63.2.177 to 92.63.2.17892.63.2.1792
17492.63.2.180/3092.63.2.181 to 92.63.2.18292.63.2.1832
17592.63.2.184/3092.63.2.185 to 92.63.2.18692.63.2.1872
17692.63.2.188/3092.63.2.189 to 92.63.2.19092.63.2.1912
17792.63.2.192/3092.63.2.193 to 92.63.2.19492.63.2.1952
17892.63.2.196/3092.63.2.197 to 92.63.2.19892.63.2.1992
17992.63.2.200/3092.63.2.201 to 92.63.2.20292.63.2.2032
18092.63.2.204/3092.63.2.205 to 92.63.2.20692.63.2.2072
18192.63.2.208/3092.63.2.209 to 92.63.2.21092.63.2.2112
18292.63.2.212/3092.63.2.213 to 92.63.2.21492.63.2.2152
18392.63.2.216/3092.63.2.217 to 92.63.2.21892.63.2.2192
18492.63.2.220/3092.63.2.221 to 92.63.2.22292.63.2.2232
18592.63.2.224/3092.63.2.225 to 92.63.2.22692.63.2.2272
18692.63.2.228/3092.63.2.229 to 92.63.2.23092.63.2.2312
18792.63.2.232/3092.63.2.233 to 92.63.2.23492.63.2.2352
18892.63.2.236/3092.63.2.237 to 92.63.2.23892.63.2.2392
18992.63.2.240/3092.63.2.241 to 92.63.2.24292.63.2.2432
19092.63.2.244/3092.63.2.245 to 92.63.2.24692.63.2.2472
19192.63.2.248/3092.63.2.249 to 92.63.2.25092.63.2.2512
19292.63.2.252/3092.63.2.253 to 92.63.2.25492.63.2.2552
19392.63.3.0/3092.63.3.1 to 92.63.3.292.63.3.32
19492.63.3.4/3092.63.3.5 to 92.63.3.692.63.3.72
19592.63.3.8/3092.63.3.9 to 92.63.3.1092.63.3.112
19692.63.3.12/3092.63.3.13 to 92.63.3.1492.63.3.152
19792.63.3.16/3092.63.3.17 to 92.63.3.1892.63.3.192
19892.63.3.20/3092.63.3.21 to 92.63.3.2292.63.3.232
19992.63.3.24/3092.63.3.25 to 92.63.3.2692.63.3.272
20092.63.3.28/3092.63.3.29 to 92.63.3.3092.63.3.312
20192.63.3.32/3092.63.3.33 to 92.63.3.3492.63.3.352
20292.63.3.36/3092.63.3.37 to 92.63.3.3892.63.3.392
20392.63.3.40/3092.63.3.41 to 92.63.3.4292.63.3.432
20492.63.3.44/3092.63.3.45 to 92.63.3.4692.63.3.472
20592.63.3.48/3092.63.3.49 to 92.63.3.5092.63.3.512
20692.63.3.52/3092.63.3.53 to 92.63.3.5492.63.3.552
20792.63.3.56/3092.63.3.57 to 92.63.3.5892.63.3.592
20892.63.3.60/3092.63.3.61 to 92.63.3.6292.63.3.632
20992.63.3.64/3092.63.3.65 to 92.63.3.6692.63.3.672
21092.63.3.68/3092.63.3.69 to 92.63.3.7092.63.3.712
21192.63.3.72/3092.63.3.73 to 92.63.3.7492.63.3.752
21292.63.3.76/3092.63.3.77 to 92.63.3.7892.63.3.792
21392.63.3.80/3092.63.3.81 to 92.63.3.8292.63.3.832
21492.63.3.84/3092.63.3.85 to 92.63.3.8692.63.3.872
21592.63.3.88/3092.63.3.89 to 92.63.3.9092.63.3.912
21692.63.3.92/3092.63.3.93 to 92.63.3.9492.63.3.952
21792.63.3.96/3092.63.3.97 to 92.63.3.9892.63.3.992
21892.63.3.100/3092.63.3.101 to 92.63.3.10292.63.3.1032
21992.63.3.104/3092.63.3.105 to 92.63.3.10692.63.3.1072
22092.63.3.108/3092.63.3.109 to 92.63.3.11092.63.3.1112
22192.63.3.112/3092.63.3.113 to 92.63.3.11492.63.3.1152
22292.63.3.116/3092.63.3.117 to 92.63.3.11892.63.3.1192
22392.63.3.120/3092.63.3.121 to 92.63.3.12292.63.3.1232
22492.63.3.124/3092.63.3.125 to 92.63.3.12692.63.3.1272
22592.63.3.128/3092.63.3.129 to 92.63.3.13092.63.3.1312
22692.63.3.132/3092.63.3.133 to 92.63.3.13492.63.3.1352
22792.63.3.136/3092.63.3.137 to 92.63.3.13892.63.3.1392
22892.63.3.140/3092.63.3.141 to 92.63.3.14292.63.3.1432
22992.63.3.144/3092.63.3.145 to 92.63.3.14692.63.3.1472
23092.63.3.148/3092.63.3.149 to 92.63.3.15092.63.3.1512
23192.63.3.152/3092.63.3.153 to 92.63.3.15492.63.3.1552
23292.63.3.156/3092.63.3.157 to 92.63.3.15892.63.3.1592
23392.63.3.160/3092.63.3.161 to 92.63.3.16292.63.3.1632
23492.63.3.164/3092.63.3.165 to 92.63.3.16692.63.3.1672
23592.63.3.168/3092.63.3.169 to 92.63.3.17092.63.3.1712
23692.63.3.172/3092.63.3.173 to 92.63.3.17492.63.3.1752
23792.63.3.176/3092.63.3.177 to 92.63.3.17892.63.3.1792
23892.63.3.180/3092.63.3.181 to 92.63.3.18292.63.3.1832
23992.63.3.184/3092.63.3.185 to 92.63.3.18692.63.3.1872
24092.63.3.188/3092.63.3.189 to 92.63.3.19092.63.3.1912
24192.63.3.192/3092.63.3.193 to 92.63.3.19492.63.3.1952
24292.63.3.196/3092.63.3.197 to 92.63.3.19892.63.3.1992
24392.63.3.200/3092.63.3.201 to 92.63.3.20292.63.3.2032
24492.63.3.204/3092.63.3.205 to 92.63.3.20692.63.3.2072
24592.63.3.208/3092.63.3.209 to 92.63.3.21092.63.3.2112
24692.63.3.212/3092.63.3.213 to 92.63.3.21492.63.3.2152
24792.63.3.216/3092.63.3.217 to 92.63.3.21892.63.3.2192
24892.63.3.220/3092.63.3.221 to 92.63.3.22292.63.3.2232
24992.63.3.224/3092.63.3.225 to 92.63.3.22692.63.3.2272
25092.63.3.228/3092.63.3.229 to 92.63.3.23092.63.3.2312
25192.63.3.232/3092.63.3.233 to 92.63.3.23492.63.3.2352
25292.63.3.236/3092.63.3.237 to 92.63.3.23892.63.3.2392
25392.63.3.240/3092.63.3.241 to 92.63.3.24292.63.3.2432
25492.63.3.244/3092.63.3.245 to 92.63.3.24692.63.3.2472
25592.63.3.248/3092.63.3.249 to 92.63.3.25092.63.3.2512
25692.63.3.252/3092.63.3.253 to 92.63.3.25492.63.3.2552

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.