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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.

Network115.2.96.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
115.2.96.0
Broadcast address
115.2.127.255
First usable
115.2.96.1
Last usable
115.2.127.254
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 73026000 · Integer 1929535488 to 1929543679
Reverse DNS zones
96.2.115.in-addr.arpa
97.2.115.in-addr.arpa
98.2.115.in-addr.arpa
99.2.115.in-addr.arpa
100.2.115.in-addr.arpa
101.2.115.in-addr.arpa
102.2.115.in-addr.arpa
103.2.115.in-addr.arpa
104.2.115.in-addr.arpa
105.2.115.in-addr.arpa
106.2.115.in-addr.arpa
107.2.115.in-addr.arpa
108.2.115.in-addr.arpa
109.2.115.in-addr.arpa
110.2.115.in-addr.arpa
111.2.115.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
Address01110011.00000010.01100000.00000000115.2.96.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network01110011.00000010.01100000.00000000115.2.96.0
Broadcast01110011.00000010.01111111.11111111115.2.127.255
Split into smaller subnets/30
/20 (2)/21 (4)/22 (8)/23 (16)/24 (32)/25 (64)/26 (128)/27 (256)/28 (512)/29 (1,024)/30 (2,048)/31 (4,096)

115.2.96.0/19 makes 2,048 subnets of /30; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1115.2.96.0/30115.2.96.1 to 115.2.96.2115.2.96.32
2115.2.96.4/30115.2.96.5 to 115.2.96.6115.2.96.72
3115.2.96.8/30115.2.96.9 to 115.2.96.10115.2.96.112
4115.2.96.12/30115.2.96.13 to 115.2.96.14115.2.96.152
5115.2.96.16/30115.2.96.17 to 115.2.96.18115.2.96.192
6115.2.96.20/30115.2.96.21 to 115.2.96.22115.2.96.232
7115.2.96.24/30115.2.96.25 to 115.2.96.26115.2.96.272
8115.2.96.28/30115.2.96.29 to 115.2.96.30115.2.96.312
9115.2.96.32/30115.2.96.33 to 115.2.96.34115.2.96.352
10115.2.96.36/30115.2.96.37 to 115.2.96.38115.2.96.392
11115.2.96.40/30115.2.96.41 to 115.2.96.42115.2.96.432
12115.2.96.44/30115.2.96.45 to 115.2.96.46115.2.96.472
13115.2.96.48/30115.2.96.49 to 115.2.96.50115.2.96.512
14115.2.96.52/30115.2.96.53 to 115.2.96.54115.2.96.552
15115.2.96.56/30115.2.96.57 to 115.2.96.58115.2.96.592
16115.2.96.60/30115.2.96.61 to 115.2.96.62115.2.96.632
17115.2.96.64/30115.2.96.65 to 115.2.96.66115.2.96.672
18115.2.96.68/30115.2.96.69 to 115.2.96.70115.2.96.712
19115.2.96.72/30115.2.96.73 to 115.2.96.74115.2.96.752
20115.2.96.76/30115.2.96.77 to 115.2.96.78115.2.96.792
21115.2.96.80/30115.2.96.81 to 115.2.96.82115.2.96.832
22115.2.96.84/30115.2.96.85 to 115.2.96.86115.2.96.872
23115.2.96.88/30115.2.96.89 to 115.2.96.90115.2.96.912
24115.2.96.92/30115.2.96.93 to 115.2.96.94115.2.96.952
25115.2.96.96/30115.2.96.97 to 115.2.96.98115.2.96.992
26115.2.96.100/30115.2.96.101 to 115.2.96.102115.2.96.1032
27115.2.96.104/30115.2.96.105 to 115.2.96.106115.2.96.1072
28115.2.96.108/30115.2.96.109 to 115.2.96.110115.2.96.1112
29115.2.96.112/30115.2.96.113 to 115.2.96.114115.2.96.1152
30115.2.96.116/30115.2.96.117 to 115.2.96.118115.2.96.1192
31115.2.96.120/30115.2.96.121 to 115.2.96.122115.2.96.1232
32115.2.96.124/30115.2.96.125 to 115.2.96.126115.2.96.1272
33115.2.96.128/30115.2.96.129 to 115.2.96.130115.2.96.1312
34115.2.96.132/30115.2.96.133 to 115.2.96.134115.2.96.1352
35115.2.96.136/30115.2.96.137 to 115.2.96.138115.2.96.1392
36115.2.96.140/30115.2.96.141 to 115.2.96.142115.2.96.1432
37115.2.96.144/30115.2.96.145 to 115.2.96.146115.2.96.1472
38115.2.96.148/30115.2.96.149 to 115.2.96.150115.2.96.1512
39115.2.96.152/30115.2.96.153 to 115.2.96.154115.2.96.1552
40115.2.96.156/30115.2.96.157 to 115.2.96.158115.2.96.1592
41115.2.96.160/30115.2.96.161 to 115.2.96.162115.2.96.1632
42115.2.96.164/30115.2.96.165 to 115.2.96.166115.2.96.1672
43115.2.96.168/30115.2.96.169 to 115.2.96.170115.2.96.1712
44115.2.96.172/30115.2.96.173 to 115.2.96.174115.2.96.1752
45115.2.96.176/30115.2.96.177 to 115.2.96.178115.2.96.1792
46115.2.96.180/30115.2.96.181 to 115.2.96.182115.2.96.1832
47115.2.96.184/30115.2.96.185 to 115.2.96.186115.2.96.1872
48115.2.96.188/30115.2.96.189 to 115.2.96.190115.2.96.1912
49115.2.96.192/30115.2.96.193 to 115.2.96.194115.2.96.1952
50115.2.96.196/30115.2.96.197 to 115.2.96.198115.2.96.1992
51115.2.96.200/30115.2.96.201 to 115.2.96.202115.2.96.2032
52115.2.96.204/30115.2.96.205 to 115.2.96.206115.2.96.2072
53115.2.96.208/30115.2.96.209 to 115.2.96.210115.2.96.2112
54115.2.96.212/30115.2.96.213 to 115.2.96.214115.2.96.2152
55115.2.96.216/30115.2.96.217 to 115.2.96.218115.2.96.2192
56115.2.96.220/30115.2.96.221 to 115.2.96.222115.2.96.2232
57115.2.96.224/30115.2.96.225 to 115.2.96.226115.2.96.2272
58115.2.96.228/30115.2.96.229 to 115.2.96.230115.2.96.2312
59115.2.96.232/30115.2.96.233 to 115.2.96.234115.2.96.2352
60115.2.96.236/30115.2.96.237 to 115.2.96.238115.2.96.2392
61115.2.96.240/30115.2.96.241 to 115.2.96.242115.2.96.2432
62115.2.96.244/30115.2.96.245 to 115.2.96.246115.2.96.2472
63115.2.96.248/30115.2.96.249 to 115.2.96.250115.2.96.2512
64115.2.96.252/30115.2.96.253 to 115.2.96.254115.2.96.2552
65115.2.97.0/30115.2.97.1 to 115.2.97.2115.2.97.32
66115.2.97.4/30115.2.97.5 to 115.2.97.6115.2.97.72
67115.2.97.8/30115.2.97.9 to 115.2.97.10115.2.97.112
68115.2.97.12/30115.2.97.13 to 115.2.97.14115.2.97.152
69115.2.97.16/30115.2.97.17 to 115.2.97.18115.2.97.192
70115.2.97.20/30115.2.97.21 to 115.2.97.22115.2.97.232
71115.2.97.24/30115.2.97.25 to 115.2.97.26115.2.97.272
72115.2.97.28/30115.2.97.29 to 115.2.97.30115.2.97.312
73115.2.97.32/30115.2.97.33 to 115.2.97.34115.2.97.352
74115.2.97.36/30115.2.97.37 to 115.2.97.38115.2.97.392
75115.2.97.40/30115.2.97.41 to 115.2.97.42115.2.97.432
76115.2.97.44/30115.2.97.45 to 115.2.97.46115.2.97.472
77115.2.97.48/30115.2.97.49 to 115.2.97.50115.2.97.512
78115.2.97.52/30115.2.97.53 to 115.2.97.54115.2.97.552
79115.2.97.56/30115.2.97.57 to 115.2.97.58115.2.97.592
80115.2.97.60/30115.2.97.61 to 115.2.97.62115.2.97.632
81115.2.97.64/30115.2.97.65 to 115.2.97.66115.2.97.672
82115.2.97.68/30115.2.97.69 to 115.2.97.70115.2.97.712
83115.2.97.72/30115.2.97.73 to 115.2.97.74115.2.97.752
84115.2.97.76/30115.2.97.77 to 115.2.97.78115.2.97.792
85115.2.97.80/30115.2.97.81 to 115.2.97.82115.2.97.832
86115.2.97.84/30115.2.97.85 to 115.2.97.86115.2.97.872
87115.2.97.88/30115.2.97.89 to 115.2.97.90115.2.97.912
88115.2.97.92/30115.2.97.93 to 115.2.97.94115.2.97.952
89115.2.97.96/30115.2.97.97 to 115.2.97.98115.2.97.992
90115.2.97.100/30115.2.97.101 to 115.2.97.102115.2.97.1032
91115.2.97.104/30115.2.97.105 to 115.2.97.106115.2.97.1072
92115.2.97.108/30115.2.97.109 to 115.2.97.110115.2.97.1112
93115.2.97.112/30115.2.97.113 to 115.2.97.114115.2.97.1152
94115.2.97.116/30115.2.97.117 to 115.2.97.118115.2.97.1192
95115.2.97.120/30115.2.97.121 to 115.2.97.122115.2.97.1232
96115.2.97.124/30115.2.97.125 to 115.2.97.126115.2.97.1272
97115.2.97.128/30115.2.97.129 to 115.2.97.130115.2.97.1312
98115.2.97.132/30115.2.97.133 to 115.2.97.134115.2.97.1352
99115.2.97.136/30115.2.97.137 to 115.2.97.138115.2.97.1392
100115.2.97.140/30115.2.97.141 to 115.2.97.142115.2.97.1432
101115.2.97.144/30115.2.97.145 to 115.2.97.146115.2.97.1472
102115.2.97.148/30115.2.97.149 to 115.2.97.150115.2.97.1512
103115.2.97.152/30115.2.97.153 to 115.2.97.154115.2.97.1552
104115.2.97.156/30115.2.97.157 to 115.2.97.158115.2.97.1592
105115.2.97.160/30115.2.97.161 to 115.2.97.162115.2.97.1632
106115.2.97.164/30115.2.97.165 to 115.2.97.166115.2.97.1672
107115.2.97.168/30115.2.97.169 to 115.2.97.170115.2.97.1712
108115.2.97.172/30115.2.97.173 to 115.2.97.174115.2.97.1752
109115.2.97.176/30115.2.97.177 to 115.2.97.178115.2.97.1792
110115.2.97.180/30115.2.97.181 to 115.2.97.182115.2.97.1832
111115.2.97.184/30115.2.97.185 to 115.2.97.186115.2.97.1872
112115.2.97.188/30115.2.97.189 to 115.2.97.190115.2.97.1912
113115.2.97.192/30115.2.97.193 to 115.2.97.194115.2.97.1952
114115.2.97.196/30115.2.97.197 to 115.2.97.198115.2.97.1992
115115.2.97.200/30115.2.97.201 to 115.2.97.202115.2.97.2032
116115.2.97.204/30115.2.97.205 to 115.2.97.206115.2.97.2072
117115.2.97.208/30115.2.97.209 to 115.2.97.210115.2.97.2112
118115.2.97.212/30115.2.97.213 to 115.2.97.214115.2.97.2152
119115.2.97.216/30115.2.97.217 to 115.2.97.218115.2.97.2192
120115.2.97.220/30115.2.97.221 to 115.2.97.222115.2.97.2232
121115.2.97.224/30115.2.97.225 to 115.2.97.226115.2.97.2272
122115.2.97.228/30115.2.97.229 to 115.2.97.230115.2.97.2312
123115.2.97.232/30115.2.97.233 to 115.2.97.234115.2.97.2352
124115.2.97.236/30115.2.97.237 to 115.2.97.238115.2.97.2392
125115.2.97.240/30115.2.97.241 to 115.2.97.242115.2.97.2432
126115.2.97.244/30115.2.97.245 to 115.2.97.246115.2.97.2472
127115.2.97.248/30115.2.97.249 to 115.2.97.250115.2.97.2512
128115.2.97.252/30115.2.97.253 to 115.2.97.254115.2.97.2552
129115.2.98.0/30115.2.98.1 to 115.2.98.2115.2.98.32
130115.2.98.4/30115.2.98.5 to 115.2.98.6115.2.98.72
131115.2.98.8/30115.2.98.9 to 115.2.98.10115.2.98.112
132115.2.98.12/30115.2.98.13 to 115.2.98.14115.2.98.152
133115.2.98.16/30115.2.98.17 to 115.2.98.18115.2.98.192
134115.2.98.20/30115.2.98.21 to 115.2.98.22115.2.98.232
135115.2.98.24/30115.2.98.25 to 115.2.98.26115.2.98.272
136115.2.98.28/30115.2.98.29 to 115.2.98.30115.2.98.312
137115.2.98.32/30115.2.98.33 to 115.2.98.34115.2.98.352
138115.2.98.36/30115.2.98.37 to 115.2.98.38115.2.98.392
139115.2.98.40/30115.2.98.41 to 115.2.98.42115.2.98.432
140115.2.98.44/30115.2.98.45 to 115.2.98.46115.2.98.472
141115.2.98.48/30115.2.98.49 to 115.2.98.50115.2.98.512
142115.2.98.52/30115.2.98.53 to 115.2.98.54115.2.98.552
143115.2.98.56/30115.2.98.57 to 115.2.98.58115.2.98.592
144115.2.98.60/30115.2.98.61 to 115.2.98.62115.2.98.632
145115.2.98.64/30115.2.98.65 to 115.2.98.66115.2.98.672
146115.2.98.68/30115.2.98.69 to 115.2.98.70115.2.98.712
147115.2.98.72/30115.2.98.73 to 115.2.98.74115.2.98.752
148115.2.98.76/30115.2.98.77 to 115.2.98.78115.2.98.792
149115.2.98.80/30115.2.98.81 to 115.2.98.82115.2.98.832
150115.2.98.84/30115.2.98.85 to 115.2.98.86115.2.98.872
151115.2.98.88/30115.2.98.89 to 115.2.98.90115.2.98.912
152115.2.98.92/30115.2.98.93 to 115.2.98.94115.2.98.952
153115.2.98.96/30115.2.98.97 to 115.2.98.98115.2.98.992
154115.2.98.100/30115.2.98.101 to 115.2.98.102115.2.98.1032
155115.2.98.104/30115.2.98.105 to 115.2.98.106115.2.98.1072
156115.2.98.108/30115.2.98.109 to 115.2.98.110115.2.98.1112
157115.2.98.112/30115.2.98.113 to 115.2.98.114115.2.98.1152
158115.2.98.116/30115.2.98.117 to 115.2.98.118115.2.98.1192
159115.2.98.120/30115.2.98.121 to 115.2.98.122115.2.98.1232
160115.2.98.124/30115.2.98.125 to 115.2.98.126115.2.98.1272
161115.2.98.128/30115.2.98.129 to 115.2.98.130115.2.98.1312
162115.2.98.132/30115.2.98.133 to 115.2.98.134115.2.98.1352
163115.2.98.136/30115.2.98.137 to 115.2.98.138115.2.98.1392
164115.2.98.140/30115.2.98.141 to 115.2.98.142115.2.98.1432
165115.2.98.144/30115.2.98.145 to 115.2.98.146115.2.98.1472
166115.2.98.148/30115.2.98.149 to 115.2.98.150115.2.98.1512
167115.2.98.152/30115.2.98.153 to 115.2.98.154115.2.98.1552
168115.2.98.156/30115.2.98.157 to 115.2.98.158115.2.98.1592
169115.2.98.160/30115.2.98.161 to 115.2.98.162115.2.98.1632
170115.2.98.164/30115.2.98.165 to 115.2.98.166115.2.98.1672
171115.2.98.168/30115.2.98.169 to 115.2.98.170115.2.98.1712
172115.2.98.172/30115.2.98.173 to 115.2.98.174115.2.98.1752
173115.2.98.176/30115.2.98.177 to 115.2.98.178115.2.98.1792
174115.2.98.180/30115.2.98.181 to 115.2.98.182115.2.98.1832
175115.2.98.184/30115.2.98.185 to 115.2.98.186115.2.98.1872
176115.2.98.188/30115.2.98.189 to 115.2.98.190115.2.98.1912
177115.2.98.192/30115.2.98.193 to 115.2.98.194115.2.98.1952
178115.2.98.196/30115.2.98.197 to 115.2.98.198115.2.98.1992
179115.2.98.200/30115.2.98.201 to 115.2.98.202115.2.98.2032
180115.2.98.204/30115.2.98.205 to 115.2.98.206115.2.98.2072
181115.2.98.208/30115.2.98.209 to 115.2.98.210115.2.98.2112
182115.2.98.212/30115.2.98.213 to 115.2.98.214115.2.98.2152
183115.2.98.216/30115.2.98.217 to 115.2.98.218115.2.98.2192
184115.2.98.220/30115.2.98.221 to 115.2.98.222115.2.98.2232
185115.2.98.224/30115.2.98.225 to 115.2.98.226115.2.98.2272
186115.2.98.228/30115.2.98.229 to 115.2.98.230115.2.98.2312
187115.2.98.232/30115.2.98.233 to 115.2.98.234115.2.98.2352
188115.2.98.236/30115.2.98.237 to 115.2.98.238115.2.98.2392
189115.2.98.240/30115.2.98.241 to 115.2.98.242115.2.98.2432
190115.2.98.244/30115.2.98.245 to 115.2.98.246115.2.98.2472
191115.2.98.248/30115.2.98.249 to 115.2.98.250115.2.98.2512
192115.2.98.252/30115.2.98.253 to 115.2.98.254115.2.98.2552
193115.2.99.0/30115.2.99.1 to 115.2.99.2115.2.99.32
194115.2.99.4/30115.2.99.5 to 115.2.99.6115.2.99.72
195115.2.99.8/30115.2.99.9 to 115.2.99.10115.2.99.112
196115.2.99.12/30115.2.99.13 to 115.2.99.14115.2.99.152
197115.2.99.16/30115.2.99.17 to 115.2.99.18115.2.99.192
198115.2.99.20/30115.2.99.21 to 115.2.99.22115.2.99.232
199115.2.99.24/30115.2.99.25 to 115.2.99.26115.2.99.272
200115.2.99.28/30115.2.99.29 to 115.2.99.30115.2.99.312
201115.2.99.32/30115.2.99.33 to 115.2.99.34115.2.99.352
202115.2.99.36/30115.2.99.37 to 115.2.99.38115.2.99.392
203115.2.99.40/30115.2.99.41 to 115.2.99.42115.2.99.432
204115.2.99.44/30115.2.99.45 to 115.2.99.46115.2.99.472
205115.2.99.48/30115.2.99.49 to 115.2.99.50115.2.99.512
206115.2.99.52/30115.2.99.53 to 115.2.99.54115.2.99.552
207115.2.99.56/30115.2.99.57 to 115.2.99.58115.2.99.592
208115.2.99.60/30115.2.99.61 to 115.2.99.62115.2.99.632
209115.2.99.64/30115.2.99.65 to 115.2.99.66115.2.99.672
210115.2.99.68/30115.2.99.69 to 115.2.99.70115.2.99.712
211115.2.99.72/30115.2.99.73 to 115.2.99.74115.2.99.752
212115.2.99.76/30115.2.99.77 to 115.2.99.78115.2.99.792
213115.2.99.80/30115.2.99.81 to 115.2.99.82115.2.99.832
214115.2.99.84/30115.2.99.85 to 115.2.99.86115.2.99.872
215115.2.99.88/30115.2.99.89 to 115.2.99.90115.2.99.912
216115.2.99.92/30115.2.99.93 to 115.2.99.94115.2.99.952
217115.2.99.96/30115.2.99.97 to 115.2.99.98115.2.99.992
218115.2.99.100/30115.2.99.101 to 115.2.99.102115.2.99.1032
219115.2.99.104/30115.2.99.105 to 115.2.99.106115.2.99.1072
220115.2.99.108/30115.2.99.109 to 115.2.99.110115.2.99.1112
221115.2.99.112/30115.2.99.113 to 115.2.99.114115.2.99.1152
222115.2.99.116/30115.2.99.117 to 115.2.99.118115.2.99.1192
223115.2.99.120/30115.2.99.121 to 115.2.99.122115.2.99.1232
224115.2.99.124/30115.2.99.125 to 115.2.99.126115.2.99.1272
225115.2.99.128/30115.2.99.129 to 115.2.99.130115.2.99.1312
226115.2.99.132/30115.2.99.133 to 115.2.99.134115.2.99.1352
227115.2.99.136/30115.2.99.137 to 115.2.99.138115.2.99.1392
228115.2.99.140/30115.2.99.141 to 115.2.99.142115.2.99.1432
229115.2.99.144/30115.2.99.145 to 115.2.99.146115.2.99.1472
230115.2.99.148/30115.2.99.149 to 115.2.99.150115.2.99.1512
231115.2.99.152/30115.2.99.153 to 115.2.99.154115.2.99.1552
232115.2.99.156/30115.2.99.157 to 115.2.99.158115.2.99.1592
233115.2.99.160/30115.2.99.161 to 115.2.99.162115.2.99.1632
234115.2.99.164/30115.2.99.165 to 115.2.99.166115.2.99.1672
235115.2.99.168/30115.2.99.169 to 115.2.99.170115.2.99.1712
236115.2.99.172/30115.2.99.173 to 115.2.99.174115.2.99.1752
237115.2.99.176/30115.2.99.177 to 115.2.99.178115.2.99.1792
238115.2.99.180/30115.2.99.181 to 115.2.99.182115.2.99.1832
239115.2.99.184/30115.2.99.185 to 115.2.99.186115.2.99.1872
240115.2.99.188/30115.2.99.189 to 115.2.99.190115.2.99.1912
241115.2.99.192/30115.2.99.193 to 115.2.99.194115.2.99.1952
242115.2.99.196/30115.2.99.197 to 115.2.99.198115.2.99.1992
243115.2.99.200/30115.2.99.201 to 115.2.99.202115.2.99.2032
244115.2.99.204/30115.2.99.205 to 115.2.99.206115.2.99.2072
245115.2.99.208/30115.2.99.209 to 115.2.99.210115.2.99.2112
246115.2.99.212/30115.2.99.213 to 115.2.99.214115.2.99.2152
247115.2.99.216/30115.2.99.217 to 115.2.99.218115.2.99.2192
248115.2.99.220/30115.2.99.221 to 115.2.99.222115.2.99.2232
249115.2.99.224/30115.2.99.225 to 115.2.99.226115.2.99.2272
250115.2.99.228/30115.2.99.229 to 115.2.99.230115.2.99.2312
251115.2.99.232/30115.2.99.233 to 115.2.99.234115.2.99.2352
252115.2.99.236/30115.2.99.237 to 115.2.99.238115.2.99.2392
253115.2.99.240/30115.2.99.241 to 115.2.99.242115.2.99.2432
254115.2.99.244/30115.2.99.245 to 115.2.99.246115.2.99.2472
255115.2.99.248/30115.2.99.249 to 115.2.99.250115.2.99.2512
256115.2.99.252/30115.2.99.253 to 115.2.99.254115.2.99.2552

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.