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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/20
/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 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1116.0.0.0/20116.0.0.1 to 116.0.15.254116.0.15.2554,094
2116.0.16.0/20116.0.16.1 to 116.0.31.254116.0.31.2554,094
3116.0.32.0/20116.0.32.1 to 116.0.47.254116.0.47.2554,094
4116.0.48.0/20116.0.48.1 to 116.0.63.254116.0.63.2554,094
5116.0.64.0/20116.0.64.1 to 116.0.79.254116.0.79.2554,094
6116.0.80.0/20116.0.80.1 to 116.0.95.254116.0.95.2554,094
7116.0.96.0/20116.0.96.1 to 116.0.111.254116.0.111.2554,094
8116.0.112.0/20116.0.112.1 to 116.0.127.254116.0.127.2554,094
9116.0.128.0/20116.0.128.1 to 116.0.143.254116.0.143.2554,094
10116.0.144.0/20116.0.144.1 to 116.0.159.254116.0.159.2554,094
11116.0.160.0/20116.0.160.1 to 116.0.175.254116.0.175.2554,094
12116.0.176.0/20116.0.176.1 to 116.0.191.254116.0.191.2554,094
13116.0.192.0/20116.0.192.1 to 116.0.207.254116.0.207.2554,094
14116.0.208.0/20116.0.208.1 to 116.0.223.254116.0.223.2554,094
15116.0.224.0/20116.0.224.1 to 116.0.239.254116.0.239.2554,094
16116.0.240.0/20116.0.240.1 to 116.0.255.254116.0.255.2554,094
17116.1.0.0/20116.1.0.1 to 116.1.15.254116.1.15.2554,094
18116.1.16.0/20116.1.16.1 to 116.1.31.254116.1.31.2554,094
19116.1.32.0/20116.1.32.1 to 116.1.47.254116.1.47.2554,094
20116.1.48.0/20116.1.48.1 to 116.1.63.254116.1.63.2554,094
21116.1.64.0/20116.1.64.1 to 116.1.79.254116.1.79.2554,094
22116.1.80.0/20116.1.80.1 to 116.1.95.254116.1.95.2554,094
23116.1.96.0/20116.1.96.1 to 116.1.111.254116.1.111.2554,094
24116.1.112.0/20116.1.112.1 to 116.1.127.254116.1.127.2554,094
25116.1.128.0/20116.1.128.1 to 116.1.143.254116.1.143.2554,094
26116.1.144.0/20116.1.144.1 to 116.1.159.254116.1.159.2554,094
27116.1.160.0/20116.1.160.1 to 116.1.175.254116.1.175.2554,094
28116.1.176.0/20116.1.176.1 to 116.1.191.254116.1.191.2554,094
29116.1.192.0/20116.1.192.1 to 116.1.207.254116.1.207.2554,094
30116.1.208.0/20116.1.208.1 to 116.1.223.254116.1.223.2554,094
31116.1.224.0/20116.1.224.1 to 116.1.239.254116.1.239.2554,094
32116.1.240.0/20116.1.240.1 to 116.1.255.254116.1.255.2554,094
33116.2.0.0/20116.2.0.1 to 116.2.15.254116.2.15.2554,094
34116.2.16.0/20116.2.16.1 to 116.2.31.254116.2.31.2554,094
35116.2.32.0/20116.2.32.1 to 116.2.47.254116.2.47.2554,094
36116.2.48.0/20116.2.48.1 to 116.2.63.254116.2.63.2554,094
37116.2.64.0/20116.2.64.1 to 116.2.79.254116.2.79.2554,094
38116.2.80.0/20116.2.80.1 to 116.2.95.254116.2.95.2554,094
39116.2.96.0/20116.2.96.1 to 116.2.111.254116.2.111.2554,094
40116.2.112.0/20116.2.112.1 to 116.2.127.254116.2.127.2554,094
41116.2.128.0/20116.2.128.1 to 116.2.143.254116.2.143.2554,094
42116.2.144.0/20116.2.144.1 to 116.2.159.254116.2.159.2554,094
43116.2.160.0/20116.2.160.1 to 116.2.175.254116.2.175.2554,094
44116.2.176.0/20116.2.176.1 to 116.2.191.254116.2.191.2554,094
45116.2.192.0/20116.2.192.1 to 116.2.207.254116.2.207.2554,094
46116.2.208.0/20116.2.208.1 to 116.2.223.254116.2.223.2554,094
47116.2.224.0/20116.2.224.1 to 116.2.239.254116.2.239.2554,094
48116.2.240.0/20116.2.240.1 to 116.2.255.254116.2.255.2554,094
49116.3.0.0/20116.3.0.1 to 116.3.15.254116.3.15.2554,094
50116.3.16.0/20116.3.16.1 to 116.3.31.254116.3.31.2554,094
51116.3.32.0/20116.3.32.1 to 116.3.47.254116.3.47.2554,094
52116.3.48.0/20116.3.48.1 to 116.3.63.254116.3.63.2554,094
53116.3.64.0/20116.3.64.1 to 116.3.79.254116.3.79.2554,094
54116.3.80.0/20116.3.80.1 to 116.3.95.254116.3.95.2554,094
55116.3.96.0/20116.3.96.1 to 116.3.111.254116.3.111.2554,094
56116.3.112.0/20116.3.112.1 to 116.3.127.254116.3.127.2554,094
57116.3.128.0/20116.3.128.1 to 116.3.143.254116.3.143.2554,094
58116.3.144.0/20116.3.144.1 to 116.3.159.254116.3.159.2554,094
59116.3.160.0/20116.3.160.1 to 116.3.175.254116.3.175.2554,094
60116.3.176.0/20116.3.176.1 to 116.3.191.254116.3.191.2554,094
61116.3.192.0/20116.3.192.1 to 116.3.207.254116.3.207.2554,094
62116.3.208.0/20116.3.208.1 to 116.3.223.254116.3.223.2554,094
63116.3.224.0/20116.3.224.1 to 116.3.239.254116.3.239.2554,094
64116.3.240.0/20116.3.240.1 to 116.3.255.254116.3.255.2554,094
65116.4.0.0/20116.4.0.1 to 116.4.15.254116.4.15.2554,094
66116.4.16.0/20116.4.16.1 to 116.4.31.254116.4.31.2554,094
67116.4.32.0/20116.4.32.1 to 116.4.47.254116.4.47.2554,094
68116.4.48.0/20116.4.48.1 to 116.4.63.254116.4.63.2554,094
69116.4.64.0/20116.4.64.1 to 116.4.79.254116.4.79.2554,094
70116.4.80.0/20116.4.80.1 to 116.4.95.254116.4.95.2554,094
71116.4.96.0/20116.4.96.1 to 116.4.111.254116.4.111.2554,094
72116.4.112.0/20116.4.112.1 to 116.4.127.254116.4.127.2554,094
73116.4.128.0/20116.4.128.1 to 116.4.143.254116.4.143.2554,094
74116.4.144.0/20116.4.144.1 to 116.4.159.254116.4.159.2554,094
75116.4.160.0/20116.4.160.1 to 116.4.175.254116.4.175.2554,094
76116.4.176.0/20116.4.176.1 to 116.4.191.254116.4.191.2554,094
77116.4.192.0/20116.4.192.1 to 116.4.207.254116.4.207.2554,094
78116.4.208.0/20116.4.208.1 to 116.4.223.254116.4.223.2554,094
79116.4.224.0/20116.4.224.1 to 116.4.239.254116.4.239.2554,094
80116.4.240.0/20116.4.240.1 to 116.4.255.254116.4.255.2554,094
81116.5.0.0/20116.5.0.1 to 116.5.15.254116.5.15.2554,094
82116.5.16.0/20116.5.16.1 to 116.5.31.254116.5.31.2554,094
83116.5.32.0/20116.5.32.1 to 116.5.47.254116.5.47.2554,094
84116.5.48.0/20116.5.48.1 to 116.5.63.254116.5.63.2554,094
85116.5.64.0/20116.5.64.1 to 116.5.79.254116.5.79.2554,094
86116.5.80.0/20116.5.80.1 to 116.5.95.254116.5.95.2554,094
87116.5.96.0/20116.5.96.1 to 116.5.111.254116.5.111.2554,094
88116.5.112.0/20116.5.112.1 to 116.5.127.254116.5.127.2554,094
89116.5.128.0/20116.5.128.1 to 116.5.143.254116.5.143.2554,094
90116.5.144.0/20116.5.144.1 to 116.5.159.254116.5.159.2554,094
91116.5.160.0/20116.5.160.1 to 116.5.175.254116.5.175.2554,094
92116.5.176.0/20116.5.176.1 to 116.5.191.254116.5.191.2554,094
93116.5.192.0/20116.5.192.1 to 116.5.207.254116.5.207.2554,094
94116.5.208.0/20116.5.208.1 to 116.5.223.254116.5.223.2554,094
95116.5.224.0/20116.5.224.1 to 116.5.239.254116.5.239.2554,094
96116.5.240.0/20116.5.240.1 to 116.5.255.254116.5.255.2554,094
97116.6.0.0/20116.6.0.1 to 116.6.15.254116.6.15.2554,094
98116.6.16.0/20116.6.16.1 to 116.6.31.254116.6.31.2554,094
99116.6.32.0/20116.6.32.1 to 116.6.47.254116.6.47.2554,094
100116.6.48.0/20116.6.48.1 to 116.6.63.254116.6.63.2554,094
101116.6.64.0/20116.6.64.1 to 116.6.79.254116.6.79.2554,094
102116.6.80.0/20116.6.80.1 to 116.6.95.254116.6.95.2554,094
103116.6.96.0/20116.6.96.1 to 116.6.111.254116.6.111.2554,094
104116.6.112.0/20116.6.112.1 to 116.6.127.254116.6.127.2554,094
105116.6.128.0/20116.6.128.1 to 116.6.143.254116.6.143.2554,094
106116.6.144.0/20116.6.144.1 to 116.6.159.254116.6.159.2554,094
107116.6.160.0/20116.6.160.1 to 116.6.175.254116.6.175.2554,094
108116.6.176.0/20116.6.176.1 to 116.6.191.254116.6.191.2554,094
109116.6.192.0/20116.6.192.1 to 116.6.207.254116.6.207.2554,094
110116.6.208.0/20116.6.208.1 to 116.6.223.254116.6.223.2554,094
111116.6.224.0/20116.6.224.1 to 116.6.239.254116.6.239.2554,094
112116.6.240.0/20116.6.240.1 to 116.6.255.254116.6.255.2554,094
113116.7.0.0/20116.7.0.1 to 116.7.15.254116.7.15.2554,094
114116.7.16.0/20116.7.16.1 to 116.7.31.254116.7.31.2554,094
115116.7.32.0/20116.7.32.1 to 116.7.47.254116.7.47.2554,094
116116.7.48.0/20116.7.48.1 to 116.7.63.254116.7.63.2554,094
117116.7.64.0/20116.7.64.1 to 116.7.79.254116.7.79.2554,094
118116.7.80.0/20116.7.80.1 to 116.7.95.254116.7.95.2554,094
119116.7.96.0/20116.7.96.1 to 116.7.111.254116.7.111.2554,094
120116.7.112.0/20116.7.112.1 to 116.7.127.254116.7.127.2554,094
121116.7.128.0/20116.7.128.1 to 116.7.143.254116.7.143.2554,094
122116.7.144.0/20116.7.144.1 to 116.7.159.254116.7.159.2554,094
123116.7.160.0/20116.7.160.1 to 116.7.175.254116.7.175.2554,094
124116.7.176.0/20116.7.176.1 to 116.7.191.254116.7.191.2554,094
125116.7.192.0/20116.7.192.1 to 116.7.207.254116.7.207.2554,094
126116.7.208.0/20116.7.208.1 to 116.7.223.254116.7.223.2554,094
127116.7.224.0/20116.7.224.1 to 116.7.239.254116.7.239.2554,094
128116.7.240.0/20116.7.240.1 to 116.7.255.254116.7.255.2554,094
129116.8.0.0/20116.8.0.1 to 116.8.15.254116.8.15.2554,094
130116.8.16.0/20116.8.16.1 to 116.8.31.254116.8.31.2554,094
131116.8.32.0/20116.8.32.1 to 116.8.47.254116.8.47.2554,094
132116.8.48.0/20116.8.48.1 to 116.8.63.254116.8.63.2554,094
133116.8.64.0/20116.8.64.1 to 116.8.79.254116.8.79.2554,094
134116.8.80.0/20116.8.80.1 to 116.8.95.254116.8.95.2554,094
135116.8.96.0/20116.8.96.1 to 116.8.111.254116.8.111.2554,094
136116.8.112.0/20116.8.112.1 to 116.8.127.254116.8.127.2554,094
137116.8.128.0/20116.8.128.1 to 116.8.143.254116.8.143.2554,094
138116.8.144.0/20116.8.144.1 to 116.8.159.254116.8.159.2554,094
139116.8.160.0/20116.8.160.1 to 116.8.175.254116.8.175.2554,094
140116.8.176.0/20116.8.176.1 to 116.8.191.254116.8.191.2554,094
141116.8.192.0/20116.8.192.1 to 116.8.207.254116.8.207.2554,094
142116.8.208.0/20116.8.208.1 to 116.8.223.254116.8.223.2554,094
143116.8.224.0/20116.8.224.1 to 116.8.239.254116.8.239.2554,094
144116.8.240.0/20116.8.240.1 to 116.8.255.254116.8.255.2554,094
145116.9.0.0/20116.9.0.1 to 116.9.15.254116.9.15.2554,094
146116.9.16.0/20116.9.16.1 to 116.9.31.254116.9.31.2554,094
147116.9.32.0/20116.9.32.1 to 116.9.47.254116.9.47.2554,094
148116.9.48.0/20116.9.48.1 to 116.9.63.254116.9.63.2554,094
149116.9.64.0/20116.9.64.1 to 116.9.79.254116.9.79.2554,094
150116.9.80.0/20116.9.80.1 to 116.9.95.254116.9.95.2554,094
151116.9.96.0/20116.9.96.1 to 116.9.111.254116.9.111.2554,094
152116.9.112.0/20116.9.112.1 to 116.9.127.254116.9.127.2554,094
153116.9.128.0/20116.9.128.1 to 116.9.143.254116.9.143.2554,094
154116.9.144.0/20116.9.144.1 to 116.9.159.254116.9.159.2554,094
155116.9.160.0/20116.9.160.1 to 116.9.175.254116.9.175.2554,094
156116.9.176.0/20116.9.176.1 to 116.9.191.254116.9.191.2554,094
157116.9.192.0/20116.9.192.1 to 116.9.207.254116.9.207.2554,094
158116.9.208.0/20116.9.208.1 to 116.9.223.254116.9.223.2554,094
159116.9.224.0/20116.9.224.1 to 116.9.239.254116.9.239.2554,094
160116.9.240.0/20116.9.240.1 to 116.9.255.254116.9.255.2554,094
161116.10.0.0/20116.10.0.1 to 116.10.15.254116.10.15.2554,094
162116.10.16.0/20116.10.16.1 to 116.10.31.254116.10.31.2554,094
163116.10.32.0/20116.10.32.1 to 116.10.47.254116.10.47.2554,094
164116.10.48.0/20116.10.48.1 to 116.10.63.254116.10.63.2554,094
165116.10.64.0/20116.10.64.1 to 116.10.79.254116.10.79.2554,094
166116.10.80.0/20116.10.80.1 to 116.10.95.254116.10.95.2554,094
167116.10.96.0/20116.10.96.1 to 116.10.111.254116.10.111.2554,094
168116.10.112.0/20116.10.112.1 to 116.10.127.254116.10.127.2554,094
169116.10.128.0/20116.10.128.1 to 116.10.143.254116.10.143.2554,094
170116.10.144.0/20116.10.144.1 to 116.10.159.254116.10.159.2554,094
171116.10.160.0/20116.10.160.1 to 116.10.175.254116.10.175.2554,094
172116.10.176.0/20116.10.176.1 to 116.10.191.254116.10.191.2554,094
173116.10.192.0/20116.10.192.1 to 116.10.207.254116.10.207.2554,094
174116.10.208.0/20116.10.208.1 to 116.10.223.254116.10.223.2554,094
175116.10.224.0/20116.10.224.1 to 116.10.239.254116.10.239.2554,094
176116.10.240.0/20116.10.240.1 to 116.10.255.254116.10.255.2554,094
177116.11.0.0/20116.11.0.1 to 116.11.15.254116.11.15.2554,094
178116.11.16.0/20116.11.16.1 to 116.11.31.254116.11.31.2554,094
179116.11.32.0/20116.11.32.1 to 116.11.47.254116.11.47.2554,094
180116.11.48.0/20116.11.48.1 to 116.11.63.254116.11.63.2554,094
181116.11.64.0/20116.11.64.1 to 116.11.79.254116.11.79.2554,094
182116.11.80.0/20116.11.80.1 to 116.11.95.254116.11.95.2554,094
183116.11.96.0/20116.11.96.1 to 116.11.111.254116.11.111.2554,094
184116.11.112.0/20116.11.112.1 to 116.11.127.254116.11.127.2554,094
185116.11.128.0/20116.11.128.1 to 116.11.143.254116.11.143.2554,094
186116.11.144.0/20116.11.144.1 to 116.11.159.254116.11.159.2554,094
187116.11.160.0/20116.11.160.1 to 116.11.175.254116.11.175.2554,094
188116.11.176.0/20116.11.176.1 to 116.11.191.254116.11.191.2554,094
189116.11.192.0/20116.11.192.1 to 116.11.207.254116.11.207.2554,094
190116.11.208.0/20116.11.208.1 to 116.11.223.254116.11.223.2554,094
191116.11.224.0/20116.11.224.1 to 116.11.239.254116.11.239.2554,094
192116.11.240.0/20116.11.240.1 to 116.11.255.254116.11.255.2554,094
193116.12.0.0/20116.12.0.1 to 116.12.15.254116.12.15.2554,094
194116.12.16.0/20116.12.16.1 to 116.12.31.254116.12.31.2554,094
195116.12.32.0/20116.12.32.1 to 116.12.47.254116.12.47.2554,094
196116.12.48.0/20116.12.48.1 to 116.12.63.254116.12.63.2554,094
197116.12.64.0/20116.12.64.1 to 116.12.79.254116.12.79.2554,094
198116.12.80.0/20116.12.80.1 to 116.12.95.254116.12.95.2554,094
199116.12.96.0/20116.12.96.1 to 116.12.111.254116.12.111.2554,094
200116.12.112.0/20116.12.112.1 to 116.12.127.254116.12.127.2554,094
201116.12.128.0/20116.12.128.1 to 116.12.143.254116.12.143.2554,094
202116.12.144.0/20116.12.144.1 to 116.12.159.254116.12.159.2554,094
203116.12.160.0/20116.12.160.1 to 116.12.175.254116.12.175.2554,094
204116.12.176.0/20116.12.176.1 to 116.12.191.254116.12.191.2554,094
205116.12.192.0/20116.12.192.1 to 116.12.207.254116.12.207.2554,094
206116.12.208.0/20116.12.208.1 to 116.12.223.254116.12.223.2554,094
207116.12.224.0/20116.12.224.1 to 116.12.239.254116.12.239.2554,094
208116.12.240.0/20116.12.240.1 to 116.12.255.254116.12.255.2554,094
209116.13.0.0/20116.13.0.1 to 116.13.15.254116.13.15.2554,094
210116.13.16.0/20116.13.16.1 to 116.13.31.254116.13.31.2554,094
211116.13.32.0/20116.13.32.1 to 116.13.47.254116.13.47.2554,094
212116.13.48.0/20116.13.48.1 to 116.13.63.254116.13.63.2554,094
213116.13.64.0/20116.13.64.1 to 116.13.79.254116.13.79.2554,094
214116.13.80.0/20116.13.80.1 to 116.13.95.254116.13.95.2554,094
215116.13.96.0/20116.13.96.1 to 116.13.111.254116.13.111.2554,094
216116.13.112.0/20116.13.112.1 to 116.13.127.254116.13.127.2554,094
217116.13.128.0/20116.13.128.1 to 116.13.143.254116.13.143.2554,094
218116.13.144.0/20116.13.144.1 to 116.13.159.254116.13.159.2554,094
219116.13.160.0/20116.13.160.1 to 116.13.175.254116.13.175.2554,094
220116.13.176.0/20116.13.176.1 to 116.13.191.254116.13.191.2554,094
221116.13.192.0/20116.13.192.1 to 116.13.207.254116.13.207.2554,094
222116.13.208.0/20116.13.208.1 to 116.13.223.254116.13.223.2554,094
223116.13.224.0/20116.13.224.1 to 116.13.239.254116.13.239.2554,094
224116.13.240.0/20116.13.240.1 to 116.13.255.254116.13.255.2554,094
225116.14.0.0/20116.14.0.1 to 116.14.15.254116.14.15.2554,094
226116.14.16.0/20116.14.16.1 to 116.14.31.254116.14.31.2554,094
227116.14.32.0/20116.14.32.1 to 116.14.47.254116.14.47.2554,094
228116.14.48.0/20116.14.48.1 to 116.14.63.254116.14.63.2554,094
229116.14.64.0/20116.14.64.1 to 116.14.79.254116.14.79.2554,094
230116.14.80.0/20116.14.80.1 to 116.14.95.254116.14.95.2554,094
231116.14.96.0/20116.14.96.1 to 116.14.111.254116.14.111.2554,094
232116.14.112.0/20116.14.112.1 to 116.14.127.254116.14.127.2554,094
233116.14.128.0/20116.14.128.1 to 116.14.143.254116.14.143.2554,094
234116.14.144.0/20116.14.144.1 to 116.14.159.254116.14.159.2554,094
235116.14.160.0/20116.14.160.1 to 116.14.175.254116.14.175.2554,094
236116.14.176.0/20116.14.176.1 to 116.14.191.254116.14.191.2554,094
237116.14.192.0/20116.14.192.1 to 116.14.207.254116.14.207.2554,094
238116.14.208.0/20116.14.208.1 to 116.14.223.254116.14.223.2554,094
239116.14.224.0/20116.14.224.1 to 116.14.239.254116.14.239.2554,094
240116.14.240.0/20116.14.240.1 to 116.14.255.254116.14.255.2554,094
241116.15.0.0/20116.15.0.1 to 116.15.15.254116.15.15.2554,094
242116.15.16.0/20116.15.16.1 to 116.15.31.254116.15.31.2554,094
243116.15.32.0/20116.15.32.1 to 116.15.47.254116.15.47.2554,094
244116.15.48.0/20116.15.48.1 to 116.15.63.254116.15.63.2554,094
245116.15.64.0/20116.15.64.1 to 116.15.79.254116.15.79.2554,094
246116.15.80.0/20116.15.80.1 to 116.15.95.254116.15.95.2554,094
247116.15.96.0/20116.15.96.1 to 116.15.111.254116.15.111.2554,094
248116.15.112.0/20116.15.112.1 to 116.15.127.254116.15.127.2554,094
249116.15.128.0/20116.15.128.1 to 116.15.143.254116.15.143.2554,094
250116.15.144.0/20116.15.144.1 to 116.15.159.254116.15.159.2554,094
251116.15.160.0/20116.15.160.1 to 116.15.175.254116.15.175.2554,094
252116.15.176.0/20116.15.176.1 to 116.15.191.254116.15.191.2554,094
253116.15.192.0/20116.15.192.1 to 116.15.207.254116.15.207.2554,094
254116.15.208.0/20116.15.208.1 to 116.15.223.254116.15.223.2554,094
255116.15.224.0/20116.15.224.1 to 116.15.239.254116.15.239.2554,094
256116.15.240.0/20116.15.240.1 to 116.15.255.254116.15.255.2554,094

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.