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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.

Network233.85.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
233.85.0.0
Broadcast address
233.85.255.255
First usable
233.85.0.1
Last usable
233.85.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E9550000 · Integer 3914661888 to 3914727423
Reverse DNS zone
85.233.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11101001.01010101..00000000.00000000233.85.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network11101001.01010101..00000000.00000000233.85.0.0
Broadcast11101001.01010101..11111111.11111111233.85.255.255
Split into smaller subnets/28

233.85.0.0/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1233.85.0.0/28233.85.0.1 to 233.85.0.14233.85.0.1514
2233.85.0.16/28233.85.0.17 to 233.85.0.30233.85.0.3114
3233.85.0.32/28233.85.0.33 to 233.85.0.46233.85.0.4714
4233.85.0.48/28233.85.0.49 to 233.85.0.62233.85.0.6314
5233.85.0.64/28233.85.0.65 to 233.85.0.78233.85.0.7914
6233.85.0.80/28233.85.0.81 to 233.85.0.94233.85.0.9514
7233.85.0.96/28233.85.0.97 to 233.85.0.110233.85.0.11114
8233.85.0.112/28233.85.0.113 to 233.85.0.126233.85.0.12714
9233.85.0.128/28233.85.0.129 to 233.85.0.142233.85.0.14314
10233.85.0.144/28233.85.0.145 to 233.85.0.158233.85.0.15914
11233.85.0.160/28233.85.0.161 to 233.85.0.174233.85.0.17514
12233.85.0.176/28233.85.0.177 to 233.85.0.190233.85.0.19114
13233.85.0.192/28233.85.0.193 to 233.85.0.206233.85.0.20714
14233.85.0.208/28233.85.0.209 to 233.85.0.222233.85.0.22314
15233.85.0.224/28233.85.0.225 to 233.85.0.238233.85.0.23914
16233.85.0.240/28233.85.0.241 to 233.85.0.254233.85.0.25514
17233.85.1.0/28233.85.1.1 to 233.85.1.14233.85.1.1514
18233.85.1.16/28233.85.1.17 to 233.85.1.30233.85.1.3114
19233.85.1.32/28233.85.1.33 to 233.85.1.46233.85.1.4714
20233.85.1.48/28233.85.1.49 to 233.85.1.62233.85.1.6314
21233.85.1.64/28233.85.1.65 to 233.85.1.78233.85.1.7914
22233.85.1.80/28233.85.1.81 to 233.85.1.94233.85.1.9514
23233.85.1.96/28233.85.1.97 to 233.85.1.110233.85.1.11114
24233.85.1.112/28233.85.1.113 to 233.85.1.126233.85.1.12714
25233.85.1.128/28233.85.1.129 to 233.85.1.142233.85.1.14314
26233.85.1.144/28233.85.1.145 to 233.85.1.158233.85.1.15914
27233.85.1.160/28233.85.1.161 to 233.85.1.174233.85.1.17514
28233.85.1.176/28233.85.1.177 to 233.85.1.190233.85.1.19114
29233.85.1.192/28233.85.1.193 to 233.85.1.206233.85.1.20714
30233.85.1.208/28233.85.1.209 to 233.85.1.222233.85.1.22314
31233.85.1.224/28233.85.1.225 to 233.85.1.238233.85.1.23914
32233.85.1.240/28233.85.1.241 to 233.85.1.254233.85.1.25514
33233.85.2.0/28233.85.2.1 to 233.85.2.14233.85.2.1514
34233.85.2.16/28233.85.2.17 to 233.85.2.30233.85.2.3114
35233.85.2.32/28233.85.2.33 to 233.85.2.46233.85.2.4714
36233.85.2.48/28233.85.2.49 to 233.85.2.62233.85.2.6314
37233.85.2.64/28233.85.2.65 to 233.85.2.78233.85.2.7914
38233.85.2.80/28233.85.2.81 to 233.85.2.94233.85.2.9514
39233.85.2.96/28233.85.2.97 to 233.85.2.110233.85.2.11114
40233.85.2.112/28233.85.2.113 to 233.85.2.126233.85.2.12714
41233.85.2.128/28233.85.2.129 to 233.85.2.142233.85.2.14314
42233.85.2.144/28233.85.2.145 to 233.85.2.158233.85.2.15914
43233.85.2.160/28233.85.2.161 to 233.85.2.174233.85.2.17514
44233.85.2.176/28233.85.2.177 to 233.85.2.190233.85.2.19114
45233.85.2.192/28233.85.2.193 to 233.85.2.206233.85.2.20714
46233.85.2.208/28233.85.2.209 to 233.85.2.222233.85.2.22314
47233.85.2.224/28233.85.2.225 to 233.85.2.238233.85.2.23914
48233.85.2.240/28233.85.2.241 to 233.85.2.254233.85.2.25514
49233.85.3.0/28233.85.3.1 to 233.85.3.14233.85.3.1514
50233.85.3.16/28233.85.3.17 to 233.85.3.30233.85.3.3114
51233.85.3.32/28233.85.3.33 to 233.85.3.46233.85.3.4714
52233.85.3.48/28233.85.3.49 to 233.85.3.62233.85.3.6314
53233.85.3.64/28233.85.3.65 to 233.85.3.78233.85.3.7914
54233.85.3.80/28233.85.3.81 to 233.85.3.94233.85.3.9514
55233.85.3.96/28233.85.3.97 to 233.85.3.110233.85.3.11114
56233.85.3.112/28233.85.3.113 to 233.85.3.126233.85.3.12714
57233.85.3.128/28233.85.3.129 to 233.85.3.142233.85.3.14314
58233.85.3.144/28233.85.3.145 to 233.85.3.158233.85.3.15914
59233.85.3.160/28233.85.3.161 to 233.85.3.174233.85.3.17514
60233.85.3.176/28233.85.3.177 to 233.85.3.190233.85.3.19114
61233.85.3.192/28233.85.3.193 to 233.85.3.206233.85.3.20714
62233.85.3.208/28233.85.3.209 to 233.85.3.222233.85.3.22314
63233.85.3.224/28233.85.3.225 to 233.85.3.238233.85.3.23914
64233.85.3.240/28233.85.3.241 to 233.85.3.254233.85.3.25514
65233.85.4.0/28233.85.4.1 to 233.85.4.14233.85.4.1514
66233.85.4.16/28233.85.4.17 to 233.85.4.30233.85.4.3114
67233.85.4.32/28233.85.4.33 to 233.85.4.46233.85.4.4714
68233.85.4.48/28233.85.4.49 to 233.85.4.62233.85.4.6314
69233.85.4.64/28233.85.4.65 to 233.85.4.78233.85.4.7914
70233.85.4.80/28233.85.4.81 to 233.85.4.94233.85.4.9514
71233.85.4.96/28233.85.4.97 to 233.85.4.110233.85.4.11114
72233.85.4.112/28233.85.4.113 to 233.85.4.126233.85.4.12714
73233.85.4.128/28233.85.4.129 to 233.85.4.142233.85.4.14314
74233.85.4.144/28233.85.4.145 to 233.85.4.158233.85.4.15914
75233.85.4.160/28233.85.4.161 to 233.85.4.174233.85.4.17514
76233.85.4.176/28233.85.4.177 to 233.85.4.190233.85.4.19114
77233.85.4.192/28233.85.4.193 to 233.85.4.206233.85.4.20714
78233.85.4.208/28233.85.4.209 to 233.85.4.222233.85.4.22314
79233.85.4.224/28233.85.4.225 to 233.85.4.238233.85.4.23914
80233.85.4.240/28233.85.4.241 to 233.85.4.254233.85.4.25514
81233.85.5.0/28233.85.5.1 to 233.85.5.14233.85.5.1514
82233.85.5.16/28233.85.5.17 to 233.85.5.30233.85.5.3114
83233.85.5.32/28233.85.5.33 to 233.85.5.46233.85.5.4714
84233.85.5.48/28233.85.5.49 to 233.85.5.62233.85.5.6314
85233.85.5.64/28233.85.5.65 to 233.85.5.78233.85.5.7914
86233.85.5.80/28233.85.5.81 to 233.85.5.94233.85.5.9514
87233.85.5.96/28233.85.5.97 to 233.85.5.110233.85.5.11114
88233.85.5.112/28233.85.5.113 to 233.85.5.126233.85.5.12714
89233.85.5.128/28233.85.5.129 to 233.85.5.142233.85.5.14314
90233.85.5.144/28233.85.5.145 to 233.85.5.158233.85.5.15914
91233.85.5.160/28233.85.5.161 to 233.85.5.174233.85.5.17514
92233.85.5.176/28233.85.5.177 to 233.85.5.190233.85.5.19114
93233.85.5.192/28233.85.5.193 to 233.85.5.206233.85.5.20714
94233.85.5.208/28233.85.5.209 to 233.85.5.222233.85.5.22314
95233.85.5.224/28233.85.5.225 to 233.85.5.238233.85.5.23914
96233.85.5.240/28233.85.5.241 to 233.85.5.254233.85.5.25514
97233.85.6.0/28233.85.6.1 to 233.85.6.14233.85.6.1514
98233.85.6.16/28233.85.6.17 to 233.85.6.30233.85.6.3114
99233.85.6.32/28233.85.6.33 to 233.85.6.46233.85.6.4714
100233.85.6.48/28233.85.6.49 to 233.85.6.62233.85.6.6314
101233.85.6.64/28233.85.6.65 to 233.85.6.78233.85.6.7914
102233.85.6.80/28233.85.6.81 to 233.85.6.94233.85.6.9514
103233.85.6.96/28233.85.6.97 to 233.85.6.110233.85.6.11114
104233.85.6.112/28233.85.6.113 to 233.85.6.126233.85.6.12714
105233.85.6.128/28233.85.6.129 to 233.85.6.142233.85.6.14314
106233.85.6.144/28233.85.6.145 to 233.85.6.158233.85.6.15914
107233.85.6.160/28233.85.6.161 to 233.85.6.174233.85.6.17514
108233.85.6.176/28233.85.6.177 to 233.85.6.190233.85.6.19114
109233.85.6.192/28233.85.6.193 to 233.85.6.206233.85.6.20714
110233.85.6.208/28233.85.6.209 to 233.85.6.222233.85.6.22314
111233.85.6.224/28233.85.6.225 to 233.85.6.238233.85.6.23914
112233.85.6.240/28233.85.6.241 to 233.85.6.254233.85.6.25514
113233.85.7.0/28233.85.7.1 to 233.85.7.14233.85.7.1514
114233.85.7.16/28233.85.7.17 to 233.85.7.30233.85.7.3114
115233.85.7.32/28233.85.7.33 to 233.85.7.46233.85.7.4714
116233.85.7.48/28233.85.7.49 to 233.85.7.62233.85.7.6314
117233.85.7.64/28233.85.7.65 to 233.85.7.78233.85.7.7914
118233.85.7.80/28233.85.7.81 to 233.85.7.94233.85.7.9514
119233.85.7.96/28233.85.7.97 to 233.85.7.110233.85.7.11114
120233.85.7.112/28233.85.7.113 to 233.85.7.126233.85.7.12714
121233.85.7.128/28233.85.7.129 to 233.85.7.142233.85.7.14314
122233.85.7.144/28233.85.7.145 to 233.85.7.158233.85.7.15914
123233.85.7.160/28233.85.7.161 to 233.85.7.174233.85.7.17514
124233.85.7.176/28233.85.7.177 to 233.85.7.190233.85.7.19114
125233.85.7.192/28233.85.7.193 to 233.85.7.206233.85.7.20714
126233.85.7.208/28233.85.7.209 to 233.85.7.222233.85.7.22314
127233.85.7.224/28233.85.7.225 to 233.85.7.238233.85.7.23914
128233.85.7.240/28233.85.7.241 to 233.85.7.254233.85.7.25514
129233.85.8.0/28233.85.8.1 to 233.85.8.14233.85.8.1514
130233.85.8.16/28233.85.8.17 to 233.85.8.30233.85.8.3114
131233.85.8.32/28233.85.8.33 to 233.85.8.46233.85.8.4714
132233.85.8.48/28233.85.8.49 to 233.85.8.62233.85.8.6314
133233.85.8.64/28233.85.8.65 to 233.85.8.78233.85.8.7914
134233.85.8.80/28233.85.8.81 to 233.85.8.94233.85.8.9514
135233.85.8.96/28233.85.8.97 to 233.85.8.110233.85.8.11114
136233.85.8.112/28233.85.8.113 to 233.85.8.126233.85.8.12714
137233.85.8.128/28233.85.8.129 to 233.85.8.142233.85.8.14314
138233.85.8.144/28233.85.8.145 to 233.85.8.158233.85.8.15914
139233.85.8.160/28233.85.8.161 to 233.85.8.174233.85.8.17514
140233.85.8.176/28233.85.8.177 to 233.85.8.190233.85.8.19114
141233.85.8.192/28233.85.8.193 to 233.85.8.206233.85.8.20714
142233.85.8.208/28233.85.8.209 to 233.85.8.222233.85.8.22314
143233.85.8.224/28233.85.8.225 to 233.85.8.238233.85.8.23914
144233.85.8.240/28233.85.8.241 to 233.85.8.254233.85.8.25514
145233.85.9.0/28233.85.9.1 to 233.85.9.14233.85.9.1514
146233.85.9.16/28233.85.9.17 to 233.85.9.30233.85.9.3114
147233.85.9.32/28233.85.9.33 to 233.85.9.46233.85.9.4714
148233.85.9.48/28233.85.9.49 to 233.85.9.62233.85.9.6314
149233.85.9.64/28233.85.9.65 to 233.85.9.78233.85.9.7914
150233.85.9.80/28233.85.9.81 to 233.85.9.94233.85.9.9514
151233.85.9.96/28233.85.9.97 to 233.85.9.110233.85.9.11114
152233.85.9.112/28233.85.9.113 to 233.85.9.126233.85.9.12714
153233.85.9.128/28233.85.9.129 to 233.85.9.142233.85.9.14314
154233.85.9.144/28233.85.9.145 to 233.85.9.158233.85.9.15914
155233.85.9.160/28233.85.9.161 to 233.85.9.174233.85.9.17514
156233.85.9.176/28233.85.9.177 to 233.85.9.190233.85.9.19114
157233.85.9.192/28233.85.9.193 to 233.85.9.206233.85.9.20714
158233.85.9.208/28233.85.9.209 to 233.85.9.222233.85.9.22314
159233.85.9.224/28233.85.9.225 to 233.85.9.238233.85.9.23914
160233.85.9.240/28233.85.9.241 to 233.85.9.254233.85.9.25514
161233.85.10.0/28233.85.10.1 to 233.85.10.14233.85.10.1514
162233.85.10.16/28233.85.10.17 to 233.85.10.30233.85.10.3114
163233.85.10.32/28233.85.10.33 to 233.85.10.46233.85.10.4714
164233.85.10.48/28233.85.10.49 to 233.85.10.62233.85.10.6314
165233.85.10.64/28233.85.10.65 to 233.85.10.78233.85.10.7914
166233.85.10.80/28233.85.10.81 to 233.85.10.94233.85.10.9514
167233.85.10.96/28233.85.10.97 to 233.85.10.110233.85.10.11114
168233.85.10.112/28233.85.10.113 to 233.85.10.126233.85.10.12714
169233.85.10.128/28233.85.10.129 to 233.85.10.142233.85.10.14314
170233.85.10.144/28233.85.10.145 to 233.85.10.158233.85.10.15914
171233.85.10.160/28233.85.10.161 to 233.85.10.174233.85.10.17514
172233.85.10.176/28233.85.10.177 to 233.85.10.190233.85.10.19114
173233.85.10.192/28233.85.10.193 to 233.85.10.206233.85.10.20714
174233.85.10.208/28233.85.10.209 to 233.85.10.222233.85.10.22314
175233.85.10.224/28233.85.10.225 to 233.85.10.238233.85.10.23914
176233.85.10.240/28233.85.10.241 to 233.85.10.254233.85.10.25514
177233.85.11.0/28233.85.11.1 to 233.85.11.14233.85.11.1514
178233.85.11.16/28233.85.11.17 to 233.85.11.30233.85.11.3114
179233.85.11.32/28233.85.11.33 to 233.85.11.46233.85.11.4714
180233.85.11.48/28233.85.11.49 to 233.85.11.62233.85.11.6314
181233.85.11.64/28233.85.11.65 to 233.85.11.78233.85.11.7914
182233.85.11.80/28233.85.11.81 to 233.85.11.94233.85.11.9514
183233.85.11.96/28233.85.11.97 to 233.85.11.110233.85.11.11114
184233.85.11.112/28233.85.11.113 to 233.85.11.126233.85.11.12714
185233.85.11.128/28233.85.11.129 to 233.85.11.142233.85.11.14314
186233.85.11.144/28233.85.11.145 to 233.85.11.158233.85.11.15914
187233.85.11.160/28233.85.11.161 to 233.85.11.174233.85.11.17514
188233.85.11.176/28233.85.11.177 to 233.85.11.190233.85.11.19114
189233.85.11.192/28233.85.11.193 to 233.85.11.206233.85.11.20714
190233.85.11.208/28233.85.11.209 to 233.85.11.222233.85.11.22314
191233.85.11.224/28233.85.11.225 to 233.85.11.238233.85.11.23914
192233.85.11.240/28233.85.11.241 to 233.85.11.254233.85.11.25514
193233.85.12.0/28233.85.12.1 to 233.85.12.14233.85.12.1514
194233.85.12.16/28233.85.12.17 to 233.85.12.30233.85.12.3114
195233.85.12.32/28233.85.12.33 to 233.85.12.46233.85.12.4714
196233.85.12.48/28233.85.12.49 to 233.85.12.62233.85.12.6314
197233.85.12.64/28233.85.12.65 to 233.85.12.78233.85.12.7914
198233.85.12.80/28233.85.12.81 to 233.85.12.94233.85.12.9514
199233.85.12.96/28233.85.12.97 to 233.85.12.110233.85.12.11114
200233.85.12.112/28233.85.12.113 to 233.85.12.126233.85.12.12714
201233.85.12.128/28233.85.12.129 to 233.85.12.142233.85.12.14314
202233.85.12.144/28233.85.12.145 to 233.85.12.158233.85.12.15914
203233.85.12.160/28233.85.12.161 to 233.85.12.174233.85.12.17514
204233.85.12.176/28233.85.12.177 to 233.85.12.190233.85.12.19114
205233.85.12.192/28233.85.12.193 to 233.85.12.206233.85.12.20714
206233.85.12.208/28233.85.12.209 to 233.85.12.222233.85.12.22314
207233.85.12.224/28233.85.12.225 to 233.85.12.238233.85.12.23914
208233.85.12.240/28233.85.12.241 to 233.85.12.254233.85.12.25514
209233.85.13.0/28233.85.13.1 to 233.85.13.14233.85.13.1514
210233.85.13.16/28233.85.13.17 to 233.85.13.30233.85.13.3114
211233.85.13.32/28233.85.13.33 to 233.85.13.46233.85.13.4714
212233.85.13.48/28233.85.13.49 to 233.85.13.62233.85.13.6314
213233.85.13.64/28233.85.13.65 to 233.85.13.78233.85.13.7914
214233.85.13.80/28233.85.13.81 to 233.85.13.94233.85.13.9514
215233.85.13.96/28233.85.13.97 to 233.85.13.110233.85.13.11114
216233.85.13.112/28233.85.13.113 to 233.85.13.126233.85.13.12714
217233.85.13.128/28233.85.13.129 to 233.85.13.142233.85.13.14314
218233.85.13.144/28233.85.13.145 to 233.85.13.158233.85.13.15914
219233.85.13.160/28233.85.13.161 to 233.85.13.174233.85.13.17514
220233.85.13.176/28233.85.13.177 to 233.85.13.190233.85.13.19114
221233.85.13.192/28233.85.13.193 to 233.85.13.206233.85.13.20714
222233.85.13.208/28233.85.13.209 to 233.85.13.222233.85.13.22314
223233.85.13.224/28233.85.13.225 to 233.85.13.238233.85.13.23914
224233.85.13.240/28233.85.13.241 to 233.85.13.254233.85.13.25514
225233.85.14.0/28233.85.14.1 to 233.85.14.14233.85.14.1514
226233.85.14.16/28233.85.14.17 to 233.85.14.30233.85.14.3114
227233.85.14.32/28233.85.14.33 to 233.85.14.46233.85.14.4714
228233.85.14.48/28233.85.14.49 to 233.85.14.62233.85.14.6314
229233.85.14.64/28233.85.14.65 to 233.85.14.78233.85.14.7914
230233.85.14.80/28233.85.14.81 to 233.85.14.94233.85.14.9514
231233.85.14.96/28233.85.14.97 to 233.85.14.110233.85.14.11114
232233.85.14.112/28233.85.14.113 to 233.85.14.126233.85.14.12714
233233.85.14.128/28233.85.14.129 to 233.85.14.142233.85.14.14314
234233.85.14.144/28233.85.14.145 to 233.85.14.158233.85.14.15914
235233.85.14.160/28233.85.14.161 to 233.85.14.174233.85.14.17514
236233.85.14.176/28233.85.14.177 to 233.85.14.190233.85.14.19114
237233.85.14.192/28233.85.14.193 to 233.85.14.206233.85.14.20714
238233.85.14.208/28233.85.14.209 to 233.85.14.222233.85.14.22314
239233.85.14.224/28233.85.14.225 to 233.85.14.238233.85.14.23914
240233.85.14.240/28233.85.14.241 to 233.85.14.254233.85.14.25514
241233.85.15.0/28233.85.15.1 to 233.85.15.14233.85.15.1514
242233.85.15.16/28233.85.15.17 to 233.85.15.30233.85.15.3114
243233.85.15.32/28233.85.15.33 to 233.85.15.46233.85.15.4714
244233.85.15.48/28233.85.15.49 to 233.85.15.62233.85.15.6314
245233.85.15.64/28233.85.15.65 to 233.85.15.78233.85.15.7914
246233.85.15.80/28233.85.15.81 to 233.85.15.94233.85.15.9514
247233.85.15.96/28233.85.15.97 to 233.85.15.110233.85.15.11114
248233.85.15.112/28233.85.15.113 to 233.85.15.126233.85.15.12714
249233.85.15.128/28233.85.15.129 to 233.85.15.142233.85.15.14314
250233.85.15.144/28233.85.15.145 to 233.85.15.158233.85.15.15914
251233.85.15.160/28233.85.15.161 to 233.85.15.174233.85.15.17514
252233.85.15.176/28233.85.15.177 to 233.85.15.190233.85.15.19114
253233.85.15.192/28233.85.15.193 to 233.85.15.206233.85.15.20714
254233.85.15.208/28233.85.15.209 to 233.85.15.222233.85.15.22314
255233.85.15.224/28233.85.15.225 to 233.85.15.238233.85.15.23914
256233.85.15.240/28233.85.15.241 to 233.85.15.254233.85.15.25514

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