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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.

Network116.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
116.0.0.0
Broadcast address
117.255.255.255
First usable
116.0.0.1
Last usable
117.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 74000000 · Integer 1946157056 to 1979711487
Reverse DNS zones
116.in-addr.arpa
117.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110100.00000000.00000000.00000000116.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01110100.00000000.00000000.00000000116.0.0.0
Broadcast01110101.11111111.11111111.11111111117.255.255.255
Split into smaller subnets/18
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

116.0.0.0/7 makes 2,048 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1116.0.0.0/18116.0.0.1 to 116.0.63.254116.0.63.25516,382
2116.0.64.0/18116.0.64.1 to 116.0.127.254116.0.127.25516,382
3116.0.128.0/18116.0.128.1 to 116.0.191.254116.0.191.25516,382
4116.0.192.0/18116.0.192.1 to 116.0.255.254116.0.255.25516,382
5116.1.0.0/18116.1.0.1 to 116.1.63.254116.1.63.25516,382
6116.1.64.0/18116.1.64.1 to 116.1.127.254116.1.127.25516,382
7116.1.128.0/18116.1.128.1 to 116.1.191.254116.1.191.25516,382
8116.1.192.0/18116.1.192.1 to 116.1.255.254116.1.255.25516,382
9116.2.0.0/18116.2.0.1 to 116.2.63.254116.2.63.25516,382
10116.2.64.0/18116.2.64.1 to 116.2.127.254116.2.127.25516,382
11116.2.128.0/18116.2.128.1 to 116.2.191.254116.2.191.25516,382
12116.2.192.0/18116.2.192.1 to 116.2.255.254116.2.255.25516,382
13116.3.0.0/18116.3.0.1 to 116.3.63.254116.3.63.25516,382
14116.3.64.0/18116.3.64.1 to 116.3.127.254116.3.127.25516,382
15116.3.128.0/18116.3.128.1 to 116.3.191.254116.3.191.25516,382
16116.3.192.0/18116.3.192.1 to 116.3.255.254116.3.255.25516,382
17116.4.0.0/18116.4.0.1 to 116.4.63.254116.4.63.25516,382
18116.4.64.0/18116.4.64.1 to 116.4.127.254116.4.127.25516,382
19116.4.128.0/18116.4.128.1 to 116.4.191.254116.4.191.25516,382
20116.4.192.0/18116.4.192.1 to 116.4.255.254116.4.255.25516,382
21116.5.0.0/18116.5.0.1 to 116.5.63.254116.5.63.25516,382
22116.5.64.0/18116.5.64.1 to 116.5.127.254116.5.127.25516,382
23116.5.128.0/18116.5.128.1 to 116.5.191.254116.5.191.25516,382
24116.5.192.0/18116.5.192.1 to 116.5.255.254116.5.255.25516,382
25116.6.0.0/18116.6.0.1 to 116.6.63.254116.6.63.25516,382
26116.6.64.0/18116.6.64.1 to 116.6.127.254116.6.127.25516,382
27116.6.128.0/18116.6.128.1 to 116.6.191.254116.6.191.25516,382
28116.6.192.0/18116.6.192.1 to 116.6.255.254116.6.255.25516,382
29116.7.0.0/18116.7.0.1 to 116.7.63.254116.7.63.25516,382
30116.7.64.0/18116.7.64.1 to 116.7.127.254116.7.127.25516,382
31116.7.128.0/18116.7.128.1 to 116.7.191.254116.7.191.25516,382
32116.7.192.0/18116.7.192.1 to 116.7.255.254116.7.255.25516,382
33116.8.0.0/18116.8.0.1 to 116.8.63.254116.8.63.25516,382
34116.8.64.0/18116.8.64.1 to 116.8.127.254116.8.127.25516,382
35116.8.128.0/18116.8.128.1 to 116.8.191.254116.8.191.25516,382
36116.8.192.0/18116.8.192.1 to 116.8.255.254116.8.255.25516,382
37116.9.0.0/18116.9.0.1 to 116.9.63.254116.9.63.25516,382
38116.9.64.0/18116.9.64.1 to 116.9.127.254116.9.127.25516,382
39116.9.128.0/18116.9.128.1 to 116.9.191.254116.9.191.25516,382
40116.9.192.0/18116.9.192.1 to 116.9.255.254116.9.255.25516,382
41116.10.0.0/18116.10.0.1 to 116.10.63.254116.10.63.25516,382
42116.10.64.0/18116.10.64.1 to 116.10.127.254116.10.127.25516,382
43116.10.128.0/18116.10.128.1 to 116.10.191.254116.10.191.25516,382
44116.10.192.0/18116.10.192.1 to 116.10.255.254116.10.255.25516,382
45116.11.0.0/18116.11.0.1 to 116.11.63.254116.11.63.25516,382
46116.11.64.0/18116.11.64.1 to 116.11.127.254116.11.127.25516,382
47116.11.128.0/18116.11.128.1 to 116.11.191.254116.11.191.25516,382
48116.11.192.0/18116.11.192.1 to 116.11.255.254116.11.255.25516,382
49116.12.0.0/18116.12.0.1 to 116.12.63.254116.12.63.25516,382
50116.12.64.0/18116.12.64.1 to 116.12.127.254116.12.127.25516,382
51116.12.128.0/18116.12.128.1 to 116.12.191.254116.12.191.25516,382
52116.12.192.0/18116.12.192.1 to 116.12.255.254116.12.255.25516,382
53116.13.0.0/18116.13.0.1 to 116.13.63.254116.13.63.25516,382
54116.13.64.0/18116.13.64.1 to 116.13.127.254116.13.127.25516,382
55116.13.128.0/18116.13.128.1 to 116.13.191.254116.13.191.25516,382
56116.13.192.0/18116.13.192.1 to 116.13.255.254116.13.255.25516,382
57116.14.0.0/18116.14.0.1 to 116.14.63.254116.14.63.25516,382
58116.14.64.0/18116.14.64.1 to 116.14.127.254116.14.127.25516,382
59116.14.128.0/18116.14.128.1 to 116.14.191.254116.14.191.25516,382
60116.14.192.0/18116.14.192.1 to 116.14.255.254116.14.255.25516,382
61116.15.0.0/18116.15.0.1 to 116.15.63.254116.15.63.25516,382
62116.15.64.0/18116.15.64.1 to 116.15.127.254116.15.127.25516,382
63116.15.128.0/18116.15.128.1 to 116.15.191.254116.15.191.25516,382
64116.15.192.0/18116.15.192.1 to 116.15.255.254116.15.255.25516,382
65116.16.0.0/18116.16.0.1 to 116.16.63.254116.16.63.25516,382
66116.16.64.0/18116.16.64.1 to 116.16.127.254116.16.127.25516,382
67116.16.128.0/18116.16.128.1 to 116.16.191.254116.16.191.25516,382
68116.16.192.0/18116.16.192.1 to 116.16.255.254116.16.255.25516,382
69116.17.0.0/18116.17.0.1 to 116.17.63.254116.17.63.25516,382
70116.17.64.0/18116.17.64.1 to 116.17.127.254116.17.127.25516,382
71116.17.128.0/18116.17.128.1 to 116.17.191.254116.17.191.25516,382
72116.17.192.0/18116.17.192.1 to 116.17.255.254116.17.255.25516,382
73116.18.0.0/18116.18.0.1 to 116.18.63.254116.18.63.25516,382
74116.18.64.0/18116.18.64.1 to 116.18.127.254116.18.127.25516,382
75116.18.128.0/18116.18.128.1 to 116.18.191.254116.18.191.25516,382
76116.18.192.0/18116.18.192.1 to 116.18.255.254116.18.255.25516,382
77116.19.0.0/18116.19.0.1 to 116.19.63.254116.19.63.25516,382
78116.19.64.0/18116.19.64.1 to 116.19.127.254116.19.127.25516,382
79116.19.128.0/18116.19.128.1 to 116.19.191.254116.19.191.25516,382
80116.19.192.0/18116.19.192.1 to 116.19.255.254116.19.255.25516,382
81116.20.0.0/18116.20.0.1 to 116.20.63.254116.20.63.25516,382
82116.20.64.0/18116.20.64.1 to 116.20.127.254116.20.127.25516,382
83116.20.128.0/18116.20.128.1 to 116.20.191.254116.20.191.25516,382
84116.20.192.0/18116.20.192.1 to 116.20.255.254116.20.255.25516,382
85116.21.0.0/18116.21.0.1 to 116.21.63.254116.21.63.25516,382
86116.21.64.0/18116.21.64.1 to 116.21.127.254116.21.127.25516,382
87116.21.128.0/18116.21.128.1 to 116.21.191.254116.21.191.25516,382
88116.21.192.0/18116.21.192.1 to 116.21.255.254116.21.255.25516,382
89116.22.0.0/18116.22.0.1 to 116.22.63.254116.22.63.25516,382
90116.22.64.0/18116.22.64.1 to 116.22.127.254116.22.127.25516,382
91116.22.128.0/18116.22.128.1 to 116.22.191.254116.22.191.25516,382
92116.22.192.0/18116.22.192.1 to 116.22.255.254116.22.255.25516,382
93116.23.0.0/18116.23.0.1 to 116.23.63.254116.23.63.25516,382
94116.23.64.0/18116.23.64.1 to 116.23.127.254116.23.127.25516,382
95116.23.128.0/18116.23.128.1 to 116.23.191.254116.23.191.25516,382
96116.23.192.0/18116.23.192.1 to 116.23.255.254116.23.255.25516,382
97116.24.0.0/18116.24.0.1 to 116.24.63.254116.24.63.25516,382
98116.24.64.0/18116.24.64.1 to 116.24.127.254116.24.127.25516,382
99116.24.128.0/18116.24.128.1 to 116.24.191.254116.24.191.25516,382
100116.24.192.0/18116.24.192.1 to 116.24.255.254116.24.255.25516,382
101116.25.0.0/18116.25.0.1 to 116.25.63.254116.25.63.25516,382
102116.25.64.0/18116.25.64.1 to 116.25.127.254116.25.127.25516,382
103116.25.128.0/18116.25.128.1 to 116.25.191.254116.25.191.25516,382
104116.25.192.0/18116.25.192.1 to 116.25.255.254116.25.255.25516,382
105116.26.0.0/18116.26.0.1 to 116.26.63.254116.26.63.25516,382
106116.26.64.0/18116.26.64.1 to 116.26.127.254116.26.127.25516,382
107116.26.128.0/18116.26.128.1 to 116.26.191.254116.26.191.25516,382
108116.26.192.0/18116.26.192.1 to 116.26.255.254116.26.255.25516,382
109116.27.0.0/18116.27.0.1 to 116.27.63.254116.27.63.25516,382
110116.27.64.0/18116.27.64.1 to 116.27.127.254116.27.127.25516,382
111116.27.128.0/18116.27.128.1 to 116.27.191.254116.27.191.25516,382
112116.27.192.0/18116.27.192.1 to 116.27.255.254116.27.255.25516,382
113116.28.0.0/18116.28.0.1 to 116.28.63.254116.28.63.25516,382
114116.28.64.0/18116.28.64.1 to 116.28.127.254116.28.127.25516,382
115116.28.128.0/18116.28.128.1 to 116.28.191.254116.28.191.25516,382
116116.28.192.0/18116.28.192.1 to 116.28.255.254116.28.255.25516,382
117116.29.0.0/18116.29.0.1 to 116.29.63.254116.29.63.25516,382
118116.29.64.0/18116.29.64.1 to 116.29.127.254116.29.127.25516,382
119116.29.128.0/18116.29.128.1 to 116.29.191.254116.29.191.25516,382
120116.29.192.0/18116.29.192.1 to 116.29.255.254116.29.255.25516,382
121116.30.0.0/18116.30.0.1 to 116.30.63.254116.30.63.25516,382
122116.30.64.0/18116.30.64.1 to 116.30.127.254116.30.127.25516,382
123116.30.128.0/18116.30.128.1 to 116.30.191.254116.30.191.25516,382
124116.30.192.0/18116.30.192.1 to 116.30.255.254116.30.255.25516,382
125116.31.0.0/18116.31.0.1 to 116.31.63.254116.31.63.25516,382
126116.31.64.0/18116.31.64.1 to 116.31.127.254116.31.127.25516,382
127116.31.128.0/18116.31.128.1 to 116.31.191.254116.31.191.25516,382
128116.31.192.0/18116.31.192.1 to 116.31.255.254116.31.255.25516,382
129116.32.0.0/18116.32.0.1 to 116.32.63.254116.32.63.25516,382
130116.32.64.0/18116.32.64.1 to 116.32.127.254116.32.127.25516,382
131116.32.128.0/18116.32.128.1 to 116.32.191.254116.32.191.25516,382
132116.32.192.0/18116.32.192.1 to 116.32.255.254116.32.255.25516,382
133116.33.0.0/18116.33.0.1 to 116.33.63.254116.33.63.25516,382
134116.33.64.0/18116.33.64.1 to 116.33.127.254116.33.127.25516,382
135116.33.128.0/18116.33.128.1 to 116.33.191.254116.33.191.25516,382
136116.33.192.0/18116.33.192.1 to 116.33.255.254116.33.255.25516,382
137116.34.0.0/18116.34.0.1 to 116.34.63.254116.34.63.25516,382
138116.34.64.0/18116.34.64.1 to 116.34.127.254116.34.127.25516,382
139116.34.128.0/18116.34.128.1 to 116.34.191.254116.34.191.25516,382
140116.34.192.0/18116.34.192.1 to 116.34.255.254116.34.255.25516,382
141116.35.0.0/18116.35.0.1 to 116.35.63.254116.35.63.25516,382
142116.35.64.0/18116.35.64.1 to 116.35.127.254116.35.127.25516,382
143116.35.128.0/18116.35.128.1 to 116.35.191.254116.35.191.25516,382
144116.35.192.0/18116.35.192.1 to 116.35.255.254116.35.255.25516,382
145116.36.0.0/18116.36.0.1 to 116.36.63.254116.36.63.25516,382
146116.36.64.0/18116.36.64.1 to 116.36.127.254116.36.127.25516,382
147116.36.128.0/18116.36.128.1 to 116.36.191.254116.36.191.25516,382
148116.36.192.0/18116.36.192.1 to 116.36.255.254116.36.255.25516,382
149116.37.0.0/18116.37.0.1 to 116.37.63.254116.37.63.25516,382
150116.37.64.0/18116.37.64.1 to 116.37.127.254116.37.127.25516,382
151116.37.128.0/18116.37.128.1 to 116.37.191.254116.37.191.25516,382
152116.37.192.0/18116.37.192.1 to 116.37.255.254116.37.255.25516,382
153116.38.0.0/18116.38.0.1 to 116.38.63.254116.38.63.25516,382
154116.38.64.0/18116.38.64.1 to 116.38.127.254116.38.127.25516,382
155116.38.128.0/18116.38.128.1 to 116.38.191.254116.38.191.25516,382
156116.38.192.0/18116.38.192.1 to 116.38.255.254116.38.255.25516,382
157116.39.0.0/18116.39.0.1 to 116.39.63.254116.39.63.25516,382
158116.39.64.0/18116.39.64.1 to 116.39.127.254116.39.127.25516,382
159116.39.128.0/18116.39.128.1 to 116.39.191.254116.39.191.25516,382
160116.39.192.0/18116.39.192.1 to 116.39.255.254116.39.255.25516,382
161116.40.0.0/18116.40.0.1 to 116.40.63.254116.40.63.25516,382
162116.40.64.0/18116.40.64.1 to 116.40.127.254116.40.127.25516,382
163116.40.128.0/18116.40.128.1 to 116.40.191.254116.40.191.25516,382
164116.40.192.0/18116.40.192.1 to 116.40.255.254116.40.255.25516,382
165116.41.0.0/18116.41.0.1 to 116.41.63.254116.41.63.25516,382
166116.41.64.0/18116.41.64.1 to 116.41.127.254116.41.127.25516,382
167116.41.128.0/18116.41.128.1 to 116.41.191.254116.41.191.25516,382
168116.41.192.0/18116.41.192.1 to 116.41.255.254116.41.255.25516,382
169116.42.0.0/18116.42.0.1 to 116.42.63.254116.42.63.25516,382
170116.42.64.0/18116.42.64.1 to 116.42.127.254116.42.127.25516,382
171116.42.128.0/18116.42.128.1 to 116.42.191.254116.42.191.25516,382
172116.42.192.0/18116.42.192.1 to 116.42.255.254116.42.255.25516,382
173116.43.0.0/18116.43.0.1 to 116.43.63.254116.43.63.25516,382
174116.43.64.0/18116.43.64.1 to 116.43.127.254116.43.127.25516,382
175116.43.128.0/18116.43.128.1 to 116.43.191.254116.43.191.25516,382
176116.43.192.0/18116.43.192.1 to 116.43.255.254116.43.255.25516,382
177116.44.0.0/18116.44.0.1 to 116.44.63.254116.44.63.25516,382
178116.44.64.0/18116.44.64.1 to 116.44.127.254116.44.127.25516,382
179116.44.128.0/18116.44.128.1 to 116.44.191.254116.44.191.25516,382
180116.44.192.0/18116.44.192.1 to 116.44.255.254116.44.255.25516,382
181116.45.0.0/18116.45.0.1 to 116.45.63.254116.45.63.25516,382
182116.45.64.0/18116.45.64.1 to 116.45.127.254116.45.127.25516,382
183116.45.128.0/18116.45.128.1 to 116.45.191.254116.45.191.25516,382
184116.45.192.0/18116.45.192.1 to 116.45.255.254116.45.255.25516,382
185116.46.0.0/18116.46.0.1 to 116.46.63.254116.46.63.25516,382
186116.46.64.0/18116.46.64.1 to 116.46.127.254116.46.127.25516,382
187116.46.128.0/18116.46.128.1 to 116.46.191.254116.46.191.25516,382
188116.46.192.0/18116.46.192.1 to 116.46.255.254116.46.255.25516,382
189116.47.0.0/18116.47.0.1 to 116.47.63.254116.47.63.25516,382
190116.47.64.0/18116.47.64.1 to 116.47.127.254116.47.127.25516,382
191116.47.128.0/18116.47.128.1 to 116.47.191.254116.47.191.25516,382
192116.47.192.0/18116.47.192.1 to 116.47.255.254116.47.255.25516,382
193116.48.0.0/18116.48.0.1 to 116.48.63.254116.48.63.25516,382
194116.48.64.0/18116.48.64.1 to 116.48.127.254116.48.127.25516,382
195116.48.128.0/18116.48.128.1 to 116.48.191.254116.48.191.25516,382
196116.48.192.0/18116.48.192.1 to 116.48.255.254116.48.255.25516,382
197116.49.0.0/18116.49.0.1 to 116.49.63.254116.49.63.25516,382
198116.49.64.0/18116.49.64.1 to 116.49.127.254116.49.127.25516,382
199116.49.128.0/18116.49.128.1 to 116.49.191.254116.49.191.25516,382
200116.49.192.0/18116.49.192.1 to 116.49.255.254116.49.255.25516,382
201116.50.0.0/18116.50.0.1 to 116.50.63.254116.50.63.25516,382
202116.50.64.0/18116.50.64.1 to 116.50.127.254116.50.127.25516,382
203116.50.128.0/18116.50.128.1 to 116.50.191.254116.50.191.25516,382
204116.50.192.0/18116.50.192.1 to 116.50.255.254116.50.255.25516,382
205116.51.0.0/18116.51.0.1 to 116.51.63.254116.51.63.25516,382
206116.51.64.0/18116.51.64.1 to 116.51.127.254116.51.127.25516,382
207116.51.128.0/18116.51.128.1 to 116.51.191.254116.51.191.25516,382
208116.51.192.0/18116.51.192.1 to 116.51.255.254116.51.255.25516,382
209116.52.0.0/18116.52.0.1 to 116.52.63.254116.52.63.25516,382
210116.52.64.0/18116.52.64.1 to 116.52.127.254116.52.127.25516,382
211116.52.128.0/18116.52.128.1 to 116.52.191.254116.52.191.25516,382
212116.52.192.0/18116.52.192.1 to 116.52.255.254116.52.255.25516,382
213116.53.0.0/18116.53.0.1 to 116.53.63.254116.53.63.25516,382
214116.53.64.0/18116.53.64.1 to 116.53.127.254116.53.127.25516,382
215116.53.128.0/18116.53.128.1 to 116.53.191.254116.53.191.25516,382
216116.53.192.0/18116.53.192.1 to 116.53.255.254116.53.255.25516,382
217116.54.0.0/18116.54.0.1 to 116.54.63.254116.54.63.25516,382
218116.54.64.0/18116.54.64.1 to 116.54.127.254116.54.127.25516,382
219116.54.128.0/18116.54.128.1 to 116.54.191.254116.54.191.25516,382
220116.54.192.0/18116.54.192.1 to 116.54.255.254116.54.255.25516,382
221116.55.0.0/18116.55.0.1 to 116.55.63.254116.55.63.25516,382
222116.55.64.0/18116.55.64.1 to 116.55.127.254116.55.127.25516,382
223116.55.128.0/18116.55.128.1 to 116.55.191.254116.55.191.25516,382
224116.55.192.0/18116.55.192.1 to 116.55.255.254116.55.255.25516,382
225116.56.0.0/18116.56.0.1 to 116.56.63.254116.56.63.25516,382
226116.56.64.0/18116.56.64.1 to 116.56.127.254116.56.127.25516,382
227116.56.128.0/18116.56.128.1 to 116.56.191.254116.56.191.25516,382
228116.56.192.0/18116.56.192.1 to 116.56.255.254116.56.255.25516,382
229116.57.0.0/18116.57.0.1 to 116.57.63.254116.57.63.25516,382
230116.57.64.0/18116.57.64.1 to 116.57.127.254116.57.127.25516,382
231116.57.128.0/18116.57.128.1 to 116.57.191.254116.57.191.25516,382
232116.57.192.0/18116.57.192.1 to 116.57.255.254116.57.255.25516,382
233116.58.0.0/18116.58.0.1 to 116.58.63.254116.58.63.25516,382
234116.58.64.0/18116.58.64.1 to 116.58.127.254116.58.127.25516,382
235116.58.128.0/18116.58.128.1 to 116.58.191.254116.58.191.25516,382
236116.58.192.0/18116.58.192.1 to 116.58.255.254116.58.255.25516,382
237116.59.0.0/18116.59.0.1 to 116.59.63.254116.59.63.25516,382
238116.59.64.0/18116.59.64.1 to 116.59.127.254116.59.127.25516,382
239116.59.128.0/18116.59.128.1 to 116.59.191.254116.59.191.25516,382
240116.59.192.0/18116.59.192.1 to 116.59.255.254116.59.255.25516,382
241116.60.0.0/18116.60.0.1 to 116.60.63.254116.60.63.25516,382
242116.60.64.0/18116.60.64.1 to 116.60.127.254116.60.127.25516,382
243116.60.128.0/18116.60.128.1 to 116.60.191.254116.60.191.25516,382
244116.60.192.0/18116.60.192.1 to 116.60.255.254116.60.255.25516,382
245116.61.0.0/18116.61.0.1 to 116.61.63.254116.61.63.25516,382
246116.61.64.0/18116.61.64.1 to 116.61.127.254116.61.127.25516,382
247116.61.128.0/18116.61.128.1 to 116.61.191.254116.61.191.25516,382
248116.61.192.0/18116.61.192.1 to 116.61.255.254116.61.255.25516,382
249116.62.0.0/18116.62.0.1 to 116.62.63.254116.62.63.25516,382
250116.62.64.0/18116.62.64.1 to 116.62.127.254116.62.127.25516,382
251116.62.128.0/18116.62.128.1 to 116.62.191.254116.62.191.25516,382
252116.62.192.0/18116.62.192.1 to 116.62.255.254116.62.255.25516,382
253116.63.0.0/18116.63.0.1 to 116.63.63.254116.63.63.25516,382
254116.63.64.0/18116.63.64.1 to 116.63.127.254116.63.127.25516,382
255116.63.128.0/18116.63.128.1 to 116.63.191.254116.63.191.25516,382
256116.63.192.0/18116.63.192.1 to 116.63.255.254116.63.255.25516,382

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.