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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.

Network116.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
116.0.0.0
Broadcast address
116.255.255.255
First usable
116.0.0.1
Last usable
116.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 74000000 · Integer 1946157056 to 1962934271
Reverse DNS zone
116.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110100..00000000.00000000.00000000116.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01110100..00000000.00000000.00000000116.0.0.0
Broadcast01110100..11111111.11111111.11111111116.255.255.255
Split into smaller subnets/19
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

116.0.0.0/8 makes 2,048 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1116.0.0.0/19116.0.0.1 to 116.0.31.254116.0.31.2558,190
2116.0.32.0/19116.0.32.1 to 116.0.63.254116.0.63.2558,190
3116.0.64.0/19116.0.64.1 to 116.0.95.254116.0.95.2558,190
4116.0.96.0/19116.0.96.1 to 116.0.127.254116.0.127.2558,190
5116.0.128.0/19116.0.128.1 to 116.0.159.254116.0.159.2558,190
6116.0.160.0/19116.0.160.1 to 116.0.191.254116.0.191.2558,190
7116.0.192.0/19116.0.192.1 to 116.0.223.254116.0.223.2558,190
8116.0.224.0/19116.0.224.1 to 116.0.255.254116.0.255.2558,190
9116.1.0.0/19116.1.0.1 to 116.1.31.254116.1.31.2558,190
10116.1.32.0/19116.1.32.1 to 116.1.63.254116.1.63.2558,190
11116.1.64.0/19116.1.64.1 to 116.1.95.254116.1.95.2558,190
12116.1.96.0/19116.1.96.1 to 116.1.127.254116.1.127.2558,190
13116.1.128.0/19116.1.128.1 to 116.1.159.254116.1.159.2558,190
14116.1.160.0/19116.1.160.1 to 116.1.191.254116.1.191.2558,190
15116.1.192.0/19116.1.192.1 to 116.1.223.254116.1.223.2558,190
16116.1.224.0/19116.1.224.1 to 116.1.255.254116.1.255.2558,190
17116.2.0.0/19116.2.0.1 to 116.2.31.254116.2.31.2558,190
18116.2.32.0/19116.2.32.1 to 116.2.63.254116.2.63.2558,190
19116.2.64.0/19116.2.64.1 to 116.2.95.254116.2.95.2558,190
20116.2.96.0/19116.2.96.1 to 116.2.127.254116.2.127.2558,190
21116.2.128.0/19116.2.128.1 to 116.2.159.254116.2.159.2558,190
22116.2.160.0/19116.2.160.1 to 116.2.191.254116.2.191.2558,190
23116.2.192.0/19116.2.192.1 to 116.2.223.254116.2.223.2558,190
24116.2.224.0/19116.2.224.1 to 116.2.255.254116.2.255.2558,190
25116.3.0.0/19116.3.0.1 to 116.3.31.254116.3.31.2558,190
26116.3.32.0/19116.3.32.1 to 116.3.63.254116.3.63.2558,190
27116.3.64.0/19116.3.64.1 to 116.3.95.254116.3.95.2558,190
28116.3.96.0/19116.3.96.1 to 116.3.127.254116.3.127.2558,190
29116.3.128.0/19116.3.128.1 to 116.3.159.254116.3.159.2558,190
30116.3.160.0/19116.3.160.1 to 116.3.191.254116.3.191.2558,190
31116.3.192.0/19116.3.192.1 to 116.3.223.254116.3.223.2558,190
32116.3.224.0/19116.3.224.1 to 116.3.255.254116.3.255.2558,190
33116.4.0.0/19116.4.0.1 to 116.4.31.254116.4.31.2558,190
34116.4.32.0/19116.4.32.1 to 116.4.63.254116.4.63.2558,190
35116.4.64.0/19116.4.64.1 to 116.4.95.254116.4.95.2558,190
36116.4.96.0/19116.4.96.1 to 116.4.127.254116.4.127.2558,190
37116.4.128.0/19116.4.128.1 to 116.4.159.254116.4.159.2558,190
38116.4.160.0/19116.4.160.1 to 116.4.191.254116.4.191.2558,190
39116.4.192.0/19116.4.192.1 to 116.4.223.254116.4.223.2558,190
40116.4.224.0/19116.4.224.1 to 116.4.255.254116.4.255.2558,190
41116.5.0.0/19116.5.0.1 to 116.5.31.254116.5.31.2558,190
42116.5.32.0/19116.5.32.1 to 116.5.63.254116.5.63.2558,190
43116.5.64.0/19116.5.64.1 to 116.5.95.254116.5.95.2558,190
44116.5.96.0/19116.5.96.1 to 116.5.127.254116.5.127.2558,190
45116.5.128.0/19116.5.128.1 to 116.5.159.254116.5.159.2558,190
46116.5.160.0/19116.5.160.1 to 116.5.191.254116.5.191.2558,190
47116.5.192.0/19116.5.192.1 to 116.5.223.254116.5.223.2558,190
48116.5.224.0/19116.5.224.1 to 116.5.255.254116.5.255.2558,190
49116.6.0.0/19116.6.0.1 to 116.6.31.254116.6.31.2558,190
50116.6.32.0/19116.6.32.1 to 116.6.63.254116.6.63.2558,190
51116.6.64.0/19116.6.64.1 to 116.6.95.254116.6.95.2558,190
52116.6.96.0/19116.6.96.1 to 116.6.127.254116.6.127.2558,190
53116.6.128.0/19116.6.128.1 to 116.6.159.254116.6.159.2558,190
54116.6.160.0/19116.6.160.1 to 116.6.191.254116.6.191.2558,190
55116.6.192.0/19116.6.192.1 to 116.6.223.254116.6.223.2558,190
56116.6.224.0/19116.6.224.1 to 116.6.255.254116.6.255.2558,190
57116.7.0.0/19116.7.0.1 to 116.7.31.254116.7.31.2558,190
58116.7.32.0/19116.7.32.1 to 116.7.63.254116.7.63.2558,190
59116.7.64.0/19116.7.64.1 to 116.7.95.254116.7.95.2558,190
60116.7.96.0/19116.7.96.1 to 116.7.127.254116.7.127.2558,190
61116.7.128.0/19116.7.128.1 to 116.7.159.254116.7.159.2558,190
62116.7.160.0/19116.7.160.1 to 116.7.191.254116.7.191.2558,190
63116.7.192.0/19116.7.192.1 to 116.7.223.254116.7.223.2558,190
64116.7.224.0/19116.7.224.1 to 116.7.255.254116.7.255.2558,190
65116.8.0.0/19116.8.0.1 to 116.8.31.254116.8.31.2558,190
66116.8.32.0/19116.8.32.1 to 116.8.63.254116.8.63.2558,190
67116.8.64.0/19116.8.64.1 to 116.8.95.254116.8.95.2558,190
68116.8.96.0/19116.8.96.1 to 116.8.127.254116.8.127.2558,190
69116.8.128.0/19116.8.128.1 to 116.8.159.254116.8.159.2558,190
70116.8.160.0/19116.8.160.1 to 116.8.191.254116.8.191.2558,190
71116.8.192.0/19116.8.192.1 to 116.8.223.254116.8.223.2558,190
72116.8.224.0/19116.8.224.1 to 116.8.255.254116.8.255.2558,190
73116.9.0.0/19116.9.0.1 to 116.9.31.254116.9.31.2558,190
74116.9.32.0/19116.9.32.1 to 116.9.63.254116.9.63.2558,190
75116.9.64.0/19116.9.64.1 to 116.9.95.254116.9.95.2558,190
76116.9.96.0/19116.9.96.1 to 116.9.127.254116.9.127.2558,190
77116.9.128.0/19116.9.128.1 to 116.9.159.254116.9.159.2558,190
78116.9.160.0/19116.9.160.1 to 116.9.191.254116.9.191.2558,190
79116.9.192.0/19116.9.192.1 to 116.9.223.254116.9.223.2558,190
80116.9.224.0/19116.9.224.1 to 116.9.255.254116.9.255.2558,190
81116.10.0.0/19116.10.0.1 to 116.10.31.254116.10.31.2558,190
82116.10.32.0/19116.10.32.1 to 116.10.63.254116.10.63.2558,190
83116.10.64.0/19116.10.64.1 to 116.10.95.254116.10.95.2558,190
84116.10.96.0/19116.10.96.1 to 116.10.127.254116.10.127.2558,190
85116.10.128.0/19116.10.128.1 to 116.10.159.254116.10.159.2558,190
86116.10.160.0/19116.10.160.1 to 116.10.191.254116.10.191.2558,190
87116.10.192.0/19116.10.192.1 to 116.10.223.254116.10.223.2558,190
88116.10.224.0/19116.10.224.1 to 116.10.255.254116.10.255.2558,190
89116.11.0.0/19116.11.0.1 to 116.11.31.254116.11.31.2558,190
90116.11.32.0/19116.11.32.1 to 116.11.63.254116.11.63.2558,190
91116.11.64.0/19116.11.64.1 to 116.11.95.254116.11.95.2558,190
92116.11.96.0/19116.11.96.1 to 116.11.127.254116.11.127.2558,190
93116.11.128.0/19116.11.128.1 to 116.11.159.254116.11.159.2558,190
94116.11.160.0/19116.11.160.1 to 116.11.191.254116.11.191.2558,190
95116.11.192.0/19116.11.192.1 to 116.11.223.254116.11.223.2558,190
96116.11.224.0/19116.11.224.1 to 116.11.255.254116.11.255.2558,190
97116.12.0.0/19116.12.0.1 to 116.12.31.254116.12.31.2558,190
98116.12.32.0/19116.12.32.1 to 116.12.63.254116.12.63.2558,190
99116.12.64.0/19116.12.64.1 to 116.12.95.254116.12.95.2558,190
100116.12.96.0/19116.12.96.1 to 116.12.127.254116.12.127.2558,190
101116.12.128.0/19116.12.128.1 to 116.12.159.254116.12.159.2558,190
102116.12.160.0/19116.12.160.1 to 116.12.191.254116.12.191.2558,190
103116.12.192.0/19116.12.192.1 to 116.12.223.254116.12.223.2558,190
104116.12.224.0/19116.12.224.1 to 116.12.255.254116.12.255.2558,190
105116.13.0.0/19116.13.0.1 to 116.13.31.254116.13.31.2558,190
106116.13.32.0/19116.13.32.1 to 116.13.63.254116.13.63.2558,190
107116.13.64.0/19116.13.64.1 to 116.13.95.254116.13.95.2558,190
108116.13.96.0/19116.13.96.1 to 116.13.127.254116.13.127.2558,190
109116.13.128.0/19116.13.128.1 to 116.13.159.254116.13.159.2558,190
110116.13.160.0/19116.13.160.1 to 116.13.191.254116.13.191.2558,190
111116.13.192.0/19116.13.192.1 to 116.13.223.254116.13.223.2558,190
112116.13.224.0/19116.13.224.1 to 116.13.255.254116.13.255.2558,190
113116.14.0.0/19116.14.0.1 to 116.14.31.254116.14.31.2558,190
114116.14.32.0/19116.14.32.1 to 116.14.63.254116.14.63.2558,190
115116.14.64.0/19116.14.64.1 to 116.14.95.254116.14.95.2558,190
116116.14.96.0/19116.14.96.1 to 116.14.127.254116.14.127.2558,190
117116.14.128.0/19116.14.128.1 to 116.14.159.254116.14.159.2558,190
118116.14.160.0/19116.14.160.1 to 116.14.191.254116.14.191.2558,190
119116.14.192.0/19116.14.192.1 to 116.14.223.254116.14.223.2558,190
120116.14.224.0/19116.14.224.1 to 116.14.255.254116.14.255.2558,190
121116.15.0.0/19116.15.0.1 to 116.15.31.254116.15.31.2558,190
122116.15.32.0/19116.15.32.1 to 116.15.63.254116.15.63.2558,190
123116.15.64.0/19116.15.64.1 to 116.15.95.254116.15.95.2558,190
124116.15.96.0/19116.15.96.1 to 116.15.127.254116.15.127.2558,190
125116.15.128.0/19116.15.128.1 to 116.15.159.254116.15.159.2558,190
126116.15.160.0/19116.15.160.1 to 116.15.191.254116.15.191.2558,190
127116.15.192.0/19116.15.192.1 to 116.15.223.254116.15.223.2558,190
128116.15.224.0/19116.15.224.1 to 116.15.255.254116.15.255.2558,190
129116.16.0.0/19116.16.0.1 to 116.16.31.254116.16.31.2558,190
130116.16.32.0/19116.16.32.1 to 116.16.63.254116.16.63.2558,190
131116.16.64.0/19116.16.64.1 to 116.16.95.254116.16.95.2558,190
132116.16.96.0/19116.16.96.1 to 116.16.127.254116.16.127.2558,190
133116.16.128.0/19116.16.128.1 to 116.16.159.254116.16.159.2558,190
134116.16.160.0/19116.16.160.1 to 116.16.191.254116.16.191.2558,190
135116.16.192.0/19116.16.192.1 to 116.16.223.254116.16.223.2558,190
136116.16.224.0/19116.16.224.1 to 116.16.255.254116.16.255.2558,190
137116.17.0.0/19116.17.0.1 to 116.17.31.254116.17.31.2558,190
138116.17.32.0/19116.17.32.1 to 116.17.63.254116.17.63.2558,190
139116.17.64.0/19116.17.64.1 to 116.17.95.254116.17.95.2558,190
140116.17.96.0/19116.17.96.1 to 116.17.127.254116.17.127.2558,190
141116.17.128.0/19116.17.128.1 to 116.17.159.254116.17.159.2558,190
142116.17.160.0/19116.17.160.1 to 116.17.191.254116.17.191.2558,190
143116.17.192.0/19116.17.192.1 to 116.17.223.254116.17.223.2558,190
144116.17.224.0/19116.17.224.1 to 116.17.255.254116.17.255.2558,190
145116.18.0.0/19116.18.0.1 to 116.18.31.254116.18.31.2558,190
146116.18.32.0/19116.18.32.1 to 116.18.63.254116.18.63.2558,190
147116.18.64.0/19116.18.64.1 to 116.18.95.254116.18.95.2558,190
148116.18.96.0/19116.18.96.1 to 116.18.127.254116.18.127.2558,190
149116.18.128.0/19116.18.128.1 to 116.18.159.254116.18.159.2558,190
150116.18.160.0/19116.18.160.1 to 116.18.191.254116.18.191.2558,190
151116.18.192.0/19116.18.192.1 to 116.18.223.254116.18.223.2558,190
152116.18.224.0/19116.18.224.1 to 116.18.255.254116.18.255.2558,190
153116.19.0.0/19116.19.0.1 to 116.19.31.254116.19.31.2558,190
154116.19.32.0/19116.19.32.1 to 116.19.63.254116.19.63.2558,190
155116.19.64.0/19116.19.64.1 to 116.19.95.254116.19.95.2558,190
156116.19.96.0/19116.19.96.1 to 116.19.127.254116.19.127.2558,190
157116.19.128.0/19116.19.128.1 to 116.19.159.254116.19.159.2558,190
158116.19.160.0/19116.19.160.1 to 116.19.191.254116.19.191.2558,190
159116.19.192.0/19116.19.192.1 to 116.19.223.254116.19.223.2558,190
160116.19.224.0/19116.19.224.1 to 116.19.255.254116.19.255.2558,190
161116.20.0.0/19116.20.0.1 to 116.20.31.254116.20.31.2558,190
162116.20.32.0/19116.20.32.1 to 116.20.63.254116.20.63.2558,190
163116.20.64.0/19116.20.64.1 to 116.20.95.254116.20.95.2558,190
164116.20.96.0/19116.20.96.1 to 116.20.127.254116.20.127.2558,190
165116.20.128.0/19116.20.128.1 to 116.20.159.254116.20.159.2558,190
166116.20.160.0/19116.20.160.1 to 116.20.191.254116.20.191.2558,190
167116.20.192.0/19116.20.192.1 to 116.20.223.254116.20.223.2558,190
168116.20.224.0/19116.20.224.1 to 116.20.255.254116.20.255.2558,190
169116.21.0.0/19116.21.0.1 to 116.21.31.254116.21.31.2558,190
170116.21.32.0/19116.21.32.1 to 116.21.63.254116.21.63.2558,190
171116.21.64.0/19116.21.64.1 to 116.21.95.254116.21.95.2558,190
172116.21.96.0/19116.21.96.1 to 116.21.127.254116.21.127.2558,190
173116.21.128.0/19116.21.128.1 to 116.21.159.254116.21.159.2558,190
174116.21.160.0/19116.21.160.1 to 116.21.191.254116.21.191.2558,190
175116.21.192.0/19116.21.192.1 to 116.21.223.254116.21.223.2558,190
176116.21.224.0/19116.21.224.1 to 116.21.255.254116.21.255.2558,190
177116.22.0.0/19116.22.0.1 to 116.22.31.254116.22.31.2558,190
178116.22.32.0/19116.22.32.1 to 116.22.63.254116.22.63.2558,190
179116.22.64.0/19116.22.64.1 to 116.22.95.254116.22.95.2558,190
180116.22.96.0/19116.22.96.1 to 116.22.127.254116.22.127.2558,190
181116.22.128.0/19116.22.128.1 to 116.22.159.254116.22.159.2558,190
182116.22.160.0/19116.22.160.1 to 116.22.191.254116.22.191.2558,190
183116.22.192.0/19116.22.192.1 to 116.22.223.254116.22.223.2558,190
184116.22.224.0/19116.22.224.1 to 116.22.255.254116.22.255.2558,190
185116.23.0.0/19116.23.0.1 to 116.23.31.254116.23.31.2558,190
186116.23.32.0/19116.23.32.1 to 116.23.63.254116.23.63.2558,190
187116.23.64.0/19116.23.64.1 to 116.23.95.254116.23.95.2558,190
188116.23.96.0/19116.23.96.1 to 116.23.127.254116.23.127.2558,190
189116.23.128.0/19116.23.128.1 to 116.23.159.254116.23.159.2558,190
190116.23.160.0/19116.23.160.1 to 116.23.191.254116.23.191.2558,190
191116.23.192.0/19116.23.192.1 to 116.23.223.254116.23.223.2558,190
192116.23.224.0/19116.23.224.1 to 116.23.255.254116.23.255.2558,190
193116.24.0.0/19116.24.0.1 to 116.24.31.254116.24.31.2558,190
194116.24.32.0/19116.24.32.1 to 116.24.63.254116.24.63.2558,190
195116.24.64.0/19116.24.64.1 to 116.24.95.254116.24.95.2558,190
196116.24.96.0/19116.24.96.1 to 116.24.127.254116.24.127.2558,190
197116.24.128.0/19116.24.128.1 to 116.24.159.254116.24.159.2558,190
198116.24.160.0/19116.24.160.1 to 116.24.191.254116.24.191.2558,190
199116.24.192.0/19116.24.192.1 to 116.24.223.254116.24.223.2558,190
200116.24.224.0/19116.24.224.1 to 116.24.255.254116.24.255.2558,190
201116.25.0.0/19116.25.0.1 to 116.25.31.254116.25.31.2558,190
202116.25.32.0/19116.25.32.1 to 116.25.63.254116.25.63.2558,190
203116.25.64.0/19116.25.64.1 to 116.25.95.254116.25.95.2558,190
204116.25.96.0/19116.25.96.1 to 116.25.127.254116.25.127.2558,190
205116.25.128.0/19116.25.128.1 to 116.25.159.254116.25.159.2558,190
206116.25.160.0/19116.25.160.1 to 116.25.191.254116.25.191.2558,190
207116.25.192.0/19116.25.192.1 to 116.25.223.254116.25.223.2558,190
208116.25.224.0/19116.25.224.1 to 116.25.255.254116.25.255.2558,190
209116.26.0.0/19116.26.0.1 to 116.26.31.254116.26.31.2558,190
210116.26.32.0/19116.26.32.1 to 116.26.63.254116.26.63.2558,190
211116.26.64.0/19116.26.64.1 to 116.26.95.254116.26.95.2558,190
212116.26.96.0/19116.26.96.1 to 116.26.127.254116.26.127.2558,190
213116.26.128.0/19116.26.128.1 to 116.26.159.254116.26.159.2558,190
214116.26.160.0/19116.26.160.1 to 116.26.191.254116.26.191.2558,190
215116.26.192.0/19116.26.192.1 to 116.26.223.254116.26.223.2558,190
216116.26.224.0/19116.26.224.1 to 116.26.255.254116.26.255.2558,190
217116.27.0.0/19116.27.0.1 to 116.27.31.254116.27.31.2558,190
218116.27.32.0/19116.27.32.1 to 116.27.63.254116.27.63.2558,190
219116.27.64.0/19116.27.64.1 to 116.27.95.254116.27.95.2558,190
220116.27.96.0/19116.27.96.1 to 116.27.127.254116.27.127.2558,190
221116.27.128.0/19116.27.128.1 to 116.27.159.254116.27.159.2558,190
222116.27.160.0/19116.27.160.1 to 116.27.191.254116.27.191.2558,190
223116.27.192.0/19116.27.192.1 to 116.27.223.254116.27.223.2558,190
224116.27.224.0/19116.27.224.1 to 116.27.255.254116.27.255.2558,190
225116.28.0.0/19116.28.0.1 to 116.28.31.254116.28.31.2558,190
226116.28.32.0/19116.28.32.1 to 116.28.63.254116.28.63.2558,190
227116.28.64.0/19116.28.64.1 to 116.28.95.254116.28.95.2558,190
228116.28.96.0/19116.28.96.1 to 116.28.127.254116.28.127.2558,190
229116.28.128.0/19116.28.128.1 to 116.28.159.254116.28.159.2558,190
230116.28.160.0/19116.28.160.1 to 116.28.191.254116.28.191.2558,190
231116.28.192.0/19116.28.192.1 to 116.28.223.254116.28.223.2558,190
232116.28.224.0/19116.28.224.1 to 116.28.255.254116.28.255.2558,190
233116.29.0.0/19116.29.0.1 to 116.29.31.254116.29.31.2558,190
234116.29.32.0/19116.29.32.1 to 116.29.63.254116.29.63.2558,190
235116.29.64.0/19116.29.64.1 to 116.29.95.254116.29.95.2558,190
236116.29.96.0/19116.29.96.1 to 116.29.127.254116.29.127.2558,190
237116.29.128.0/19116.29.128.1 to 116.29.159.254116.29.159.2558,190
238116.29.160.0/19116.29.160.1 to 116.29.191.254116.29.191.2558,190
239116.29.192.0/19116.29.192.1 to 116.29.223.254116.29.223.2558,190
240116.29.224.0/19116.29.224.1 to 116.29.255.254116.29.255.2558,190
241116.30.0.0/19116.30.0.1 to 116.30.31.254116.30.31.2558,190
242116.30.32.0/19116.30.32.1 to 116.30.63.254116.30.63.2558,190
243116.30.64.0/19116.30.64.1 to 116.30.95.254116.30.95.2558,190
244116.30.96.0/19116.30.96.1 to 116.30.127.254116.30.127.2558,190
245116.30.128.0/19116.30.128.1 to 116.30.159.254116.30.159.2558,190
246116.30.160.0/19116.30.160.1 to 116.30.191.254116.30.191.2558,190
247116.30.192.0/19116.30.192.1 to 116.30.223.254116.30.223.2558,190
248116.30.224.0/19116.30.224.1 to 116.30.255.254116.30.255.2558,190
249116.31.0.0/19116.31.0.1 to 116.31.31.254116.31.31.2558,190
250116.31.32.0/19116.31.32.1 to 116.31.63.254116.31.63.2558,190
251116.31.64.0/19116.31.64.1 to 116.31.95.254116.31.95.2558,190
252116.31.96.0/19116.31.96.1 to 116.31.127.254116.31.127.2558,190
253116.31.128.0/19116.31.128.1 to 116.31.159.254116.31.159.2558,190
254116.31.160.0/19116.31.160.1 to 116.31.191.254116.31.191.2558,190
255116.31.192.0/19116.31.192.1 to 116.31.223.254116.31.223.2558,190
256116.31.224.0/19116.31.224.1 to 116.31.255.254116.31.255.2558,190

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.