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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.

Network141.90.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
141.90.0.0
Broadcast address
141.90.127.255
First usable
141.90.0.1
Last usable
141.90.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Public public
Old class
B (default /16)
As numbers
Hex 8D5A0000 · Integer 2371485696 to 2371518463
Reverse DNS zones
0.90.141.in-addr.arpa
1.90.141.in-addr.arpa
2.90.141.in-addr.arpa
3.90.141.in-addr.arpa
4.90.141.in-addr.arpa
5.90.141.in-addr.arpa
6.90.141.in-addr.arpa
7.90.141.in-addr.arpa
8.90.141.in-addr.arpa
9.90.141.in-addr.arpa
10.90.141.in-addr.arpa
11.90.141.in-addr.arpa
12.90.141.in-addr.arpa
13.90.141.in-addr.arpa
14.90.141.in-addr.arpa
15.90.141.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10001101.01011010.00000000.00000000141.90.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network10001101.01011010.00000000.00000000141.90.0.0
Broadcast10001101.01011010.01111111.11111111141.90.127.255
Split into smaller subnets/29

141.90.0.0/17 makes 4,096 subnets of /29; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1141.90.0.0/29141.90.0.1 to 141.90.0.6141.90.0.76
2141.90.0.8/29141.90.0.9 to 141.90.0.14141.90.0.156
3141.90.0.16/29141.90.0.17 to 141.90.0.22141.90.0.236
4141.90.0.24/29141.90.0.25 to 141.90.0.30141.90.0.316
5141.90.0.32/29141.90.0.33 to 141.90.0.38141.90.0.396
6141.90.0.40/29141.90.0.41 to 141.90.0.46141.90.0.476
7141.90.0.48/29141.90.0.49 to 141.90.0.54141.90.0.556
8141.90.0.56/29141.90.0.57 to 141.90.0.62141.90.0.636
9141.90.0.64/29141.90.0.65 to 141.90.0.70141.90.0.716
10141.90.0.72/29141.90.0.73 to 141.90.0.78141.90.0.796
11141.90.0.80/29141.90.0.81 to 141.90.0.86141.90.0.876
12141.90.0.88/29141.90.0.89 to 141.90.0.94141.90.0.956
13141.90.0.96/29141.90.0.97 to 141.90.0.102141.90.0.1036
14141.90.0.104/29141.90.0.105 to 141.90.0.110141.90.0.1116
15141.90.0.112/29141.90.0.113 to 141.90.0.118141.90.0.1196
16141.90.0.120/29141.90.0.121 to 141.90.0.126141.90.0.1276
17141.90.0.128/29141.90.0.129 to 141.90.0.134141.90.0.1356
18141.90.0.136/29141.90.0.137 to 141.90.0.142141.90.0.1436
19141.90.0.144/29141.90.0.145 to 141.90.0.150141.90.0.1516
20141.90.0.152/29141.90.0.153 to 141.90.0.158141.90.0.1596
21141.90.0.160/29141.90.0.161 to 141.90.0.166141.90.0.1676
22141.90.0.168/29141.90.0.169 to 141.90.0.174141.90.0.1756
23141.90.0.176/29141.90.0.177 to 141.90.0.182141.90.0.1836
24141.90.0.184/29141.90.0.185 to 141.90.0.190141.90.0.1916
25141.90.0.192/29141.90.0.193 to 141.90.0.198141.90.0.1996
26141.90.0.200/29141.90.0.201 to 141.90.0.206141.90.0.2076
27141.90.0.208/29141.90.0.209 to 141.90.0.214141.90.0.2156
28141.90.0.216/29141.90.0.217 to 141.90.0.222141.90.0.2236
29141.90.0.224/29141.90.0.225 to 141.90.0.230141.90.0.2316
30141.90.0.232/29141.90.0.233 to 141.90.0.238141.90.0.2396
31141.90.0.240/29141.90.0.241 to 141.90.0.246141.90.0.2476
32141.90.0.248/29141.90.0.249 to 141.90.0.254141.90.0.2556
33141.90.1.0/29141.90.1.1 to 141.90.1.6141.90.1.76
34141.90.1.8/29141.90.1.9 to 141.90.1.14141.90.1.156
35141.90.1.16/29141.90.1.17 to 141.90.1.22141.90.1.236
36141.90.1.24/29141.90.1.25 to 141.90.1.30141.90.1.316
37141.90.1.32/29141.90.1.33 to 141.90.1.38141.90.1.396
38141.90.1.40/29141.90.1.41 to 141.90.1.46141.90.1.476
39141.90.1.48/29141.90.1.49 to 141.90.1.54141.90.1.556
40141.90.1.56/29141.90.1.57 to 141.90.1.62141.90.1.636
41141.90.1.64/29141.90.1.65 to 141.90.1.70141.90.1.716
42141.90.1.72/29141.90.1.73 to 141.90.1.78141.90.1.796
43141.90.1.80/29141.90.1.81 to 141.90.1.86141.90.1.876
44141.90.1.88/29141.90.1.89 to 141.90.1.94141.90.1.956
45141.90.1.96/29141.90.1.97 to 141.90.1.102141.90.1.1036
46141.90.1.104/29141.90.1.105 to 141.90.1.110141.90.1.1116
47141.90.1.112/29141.90.1.113 to 141.90.1.118141.90.1.1196
48141.90.1.120/29141.90.1.121 to 141.90.1.126141.90.1.1276
49141.90.1.128/29141.90.1.129 to 141.90.1.134141.90.1.1356
50141.90.1.136/29141.90.1.137 to 141.90.1.142141.90.1.1436
51141.90.1.144/29141.90.1.145 to 141.90.1.150141.90.1.1516
52141.90.1.152/29141.90.1.153 to 141.90.1.158141.90.1.1596
53141.90.1.160/29141.90.1.161 to 141.90.1.166141.90.1.1676
54141.90.1.168/29141.90.1.169 to 141.90.1.174141.90.1.1756
55141.90.1.176/29141.90.1.177 to 141.90.1.182141.90.1.1836
56141.90.1.184/29141.90.1.185 to 141.90.1.190141.90.1.1916
57141.90.1.192/29141.90.1.193 to 141.90.1.198141.90.1.1996
58141.90.1.200/29141.90.1.201 to 141.90.1.206141.90.1.2076
59141.90.1.208/29141.90.1.209 to 141.90.1.214141.90.1.2156
60141.90.1.216/29141.90.1.217 to 141.90.1.222141.90.1.2236
61141.90.1.224/29141.90.1.225 to 141.90.1.230141.90.1.2316
62141.90.1.232/29141.90.1.233 to 141.90.1.238141.90.1.2396
63141.90.1.240/29141.90.1.241 to 141.90.1.246141.90.1.2476
64141.90.1.248/29141.90.1.249 to 141.90.1.254141.90.1.2556
65141.90.2.0/29141.90.2.1 to 141.90.2.6141.90.2.76
66141.90.2.8/29141.90.2.9 to 141.90.2.14141.90.2.156
67141.90.2.16/29141.90.2.17 to 141.90.2.22141.90.2.236
68141.90.2.24/29141.90.2.25 to 141.90.2.30141.90.2.316
69141.90.2.32/29141.90.2.33 to 141.90.2.38141.90.2.396
70141.90.2.40/29141.90.2.41 to 141.90.2.46141.90.2.476
71141.90.2.48/29141.90.2.49 to 141.90.2.54141.90.2.556
72141.90.2.56/29141.90.2.57 to 141.90.2.62141.90.2.636
73141.90.2.64/29141.90.2.65 to 141.90.2.70141.90.2.716
74141.90.2.72/29141.90.2.73 to 141.90.2.78141.90.2.796
75141.90.2.80/29141.90.2.81 to 141.90.2.86141.90.2.876
76141.90.2.88/29141.90.2.89 to 141.90.2.94141.90.2.956
77141.90.2.96/29141.90.2.97 to 141.90.2.102141.90.2.1036
78141.90.2.104/29141.90.2.105 to 141.90.2.110141.90.2.1116
79141.90.2.112/29141.90.2.113 to 141.90.2.118141.90.2.1196
80141.90.2.120/29141.90.2.121 to 141.90.2.126141.90.2.1276
81141.90.2.128/29141.90.2.129 to 141.90.2.134141.90.2.1356
82141.90.2.136/29141.90.2.137 to 141.90.2.142141.90.2.1436
83141.90.2.144/29141.90.2.145 to 141.90.2.150141.90.2.1516
84141.90.2.152/29141.90.2.153 to 141.90.2.158141.90.2.1596
85141.90.2.160/29141.90.2.161 to 141.90.2.166141.90.2.1676
86141.90.2.168/29141.90.2.169 to 141.90.2.174141.90.2.1756
87141.90.2.176/29141.90.2.177 to 141.90.2.182141.90.2.1836
88141.90.2.184/29141.90.2.185 to 141.90.2.190141.90.2.1916
89141.90.2.192/29141.90.2.193 to 141.90.2.198141.90.2.1996
90141.90.2.200/29141.90.2.201 to 141.90.2.206141.90.2.2076
91141.90.2.208/29141.90.2.209 to 141.90.2.214141.90.2.2156
92141.90.2.216/29141.90.2.217 to 141.90.2.222141.90.2.2236
93141.90.2.224/29141.90.2.225 to 141.90.2.230141.90.2.2316
94141.90.2.232/29141.90.2.233 to 141.90.2.238141.90.2.2396
95141.90.2.240/29141.90.2.241 to 141.90.2.246141.90.2.2476
96141.90.2.248/29141.90.2.249 to 141.90.2.254141.90.2.2556
97141.90.3.0/29141.90.3.1 to 141.90.3.6141.90.3.76
98141.90.3.8/29141.90.3.9 to 141.90.3.14141.90.3.156
99141.90.3.16/29141.90.3.17 to 141.90.3.22141.90.3.236
100141.90.3.24/29141.90.3.25 to 141.90.3.30141.90.3.316
101141.90.3.32/29141.90.3.33 to 141.90.3.38141.90.3.396
102141.90.3.40/29141.90.3.41 to 141.90.3.46141.90.3.476
103141.90.3.48/29141.90.3.49 to 141.90.3.54141.90.3.556
104141.90.3.56/29141.90.3.57 to 141.90.3.62141.90.3.636
105141.90.3.64/29141.90.3.65 to 141.90.3.70141.90.3.716
106141.90.3.72/29141.90.3.73 to 141.90.3.78141.90.3.796
107141.90.3.80/29141.90.3.81 to 141.90.3.86141.90.3.876
108141.90.3.88/29141.90.3.89 to 141.90.3.94141.90.3.956
109141.90.3.96/29141.90.3.97 to 141.90.3.102141.90.3.1036
110141.90.3.104/29141.90.3.105 to 141.90.3.110141.90.3.1116
111141.90.3.112/29141.90.3.113 to 141.90.3.118141.90.3.1196
112141.90.3.120/29141.90.3.121 to 141.90.3.126141.90.3.1276
113141.90.3.128/29141.90.3.129 to 141.90.3.134141.90.3.1356
114141.90.3.136/29141.90.3.137 to 141.90.3.142141.90.3.1436
115141.90.3.144/29141.90.3.145 to 141.90.3.150141.90.3.1516
116141.90.3.152/29141.90.3.153 to 141.90.3.158141.90.3.1596
117141.90.3.160/29141.90.3.161 to 141.90.3.166141.90.3.1676
118141.90.3.168/29141.90.3.169 to 141.90.3.174141.90.3.1756
119141.90.3.176/29141.90.3.177 to 141.90.3.182141.90.3.1836
120141.90.3.184/29141.90.3.185 to 141.90.3.190141.90.3.1916
121141.90.3.192/29141.90.3.193 to 141.90.3.198141.90.3.1996
122141.90.3.200/29141.90.3.201 to 141.90.3.206141.90.3.2076
123141.90.3.208/29141.90.3.209 to 141.90.3.214141.90.3.2156
124141.90.3.216/29141.90.3.217 to 141.90.3.222141.90.3.2236
125141.90.3.224/29141.90.3.225 to 141.90.3.230141.90.3.2316
126141.90.3.232/29141.90.3.233 to 141.90.3.238141.90.3.2396
127141.90.3.240/29141.90.3.241 to 141.90.3.246141.90.3.2476
128141.90.3.248/29141.90.3.249 to 141.90.3.254141.90.3.2556
129141.90.4.0/29141.90.4.1 to 141.90.4.6141.90.4.76
130141.90.4.8/29141.90.4.9 to 141.90.4.14141.90.4.156
131141.90.4.16/29141.90.4.17 to 141.90.4.22141.90.4.236
132141.90.4.24/29141.90.4.25 to 141.90.4.30141.90.4.316
133141.90.4.32/29141.90.4.33 to 141.90.4.38141.90.4.396
134141.90.4.40/29141.90.4.41 to 141.90.4.46141.90.4.476
135141.90.4.48/29141.90.4.49 to 141.90.4.54141.90.4.556
136141.90.4.56/29141.90.4.57 to 141.90.4.62141.90.4.636
137141.90.4.64/29141.90.4.65 to 141.90.4.70141.90.4.716
138141.90.4.72/29141.90.4.73 to 141.90.4.78141.90.4.796
139141.90.4.80/29141.90.4.81 to 141.90.4.86141.90.4.876
140141.90.4.88/29141.90.4.89 to 141.90.4.94141.90.4.956
141141.90.4.96/29141.90.4.97 to 141.90.4.102141.90.4.1036
142141.90.4.104/29141.90.4.105 to 141.90.4.110141.90.4.1116
143141.90.4.112/29141.90.4.113 to 141.90.4.118141.90.4.1196
144141.90.4.120/29141.90.4.121 to 141.90.4.126141.90.4.1276
145141.90.4.128/29141.90.4.129 to 141.90.4.134141.90.4.1356
146141.90.4.136/29141.90.4.137 to 141.90.4.142141.90.4.1436
147141.90.4.144/29141.90.4.145 to 141.90.4.150141.90.4.1516
148141.90.4.152/29141.90.4.153 to 141.90.4.158141.90.4.1596
149141.90.4.160/29141.90.4.161 to 141.90.4.166141.90.4.1676
150141.90.4.168/29141.90.4.169 to 141.90.4.174141.90.4.1756
151141.90.4.176/29141.90.4.177 to 141.90.4.182141.90.4.1836
152141.90.4.184/29141.90.4.185 to 141.90.4.190141.90.4.1916
153141.90.4.192/29141.90.4.193 to 141.90.4.198141.90.4.1996
154141.90.4.200/29141.90.4.201 to 141.90.4.206141.90.4.2076
155141.90.4.208/29141.90.4.209 to 141.90.4.214141.90.4.2156
156141.90.4.216/29141.90.4.217 to 141.90.4.222141.90.4.2236
157141.90.4.224/29141.90.4.225 to 141.90.4.230141.90.4.2316
158141.90.4.232/29141.90.4.233 to 141.90.4.238141.90.4.2396
159141.90.4.240/29141.90.4.241 to 141.90.4.246141.90.4.2476
160141.90.4.248/29141.90.4.249 to 141.90.4.254141.90.4.2556
161141.90.5.0/29141.90.5.1 to 141.90.5.6141.90.5.76
162141.90.5.8/29141.90.5.9 to 141.90.5.14141.90.5.156
163141.90.5.16/29141.90.5.17 to 141.90.5.22141.90.5.236
164141.90.5.24/29141.90.5.25 to 141.90.5.30141.90.5.316
165141.90.5.32/29141.90.5.33 to 141.90.5.38141.90.5.396
166141.90.5.40/29141.90.5.41 to 141.90.5.46141.90.5.476
167141.90.5.48/29141.90.5.49 to 141.90.5.54141.90.5.556
168141.90.5.56/29141.90.5.57 to 141.90.5.62141.90.5.636
169141.90.5.64/29141.90.5.65 to 141.90.5.70141.90.5.716
170141.90.5.72/29141.90.5.73 to 141.90.5.78141.90.5.796
171141.90.5.80/29141.90.5.81 to 141.90.5.86141.90.5.876
172141.90.5.88/29141.90.5.89 to 141.90.5.94141.90.5.956
173141.90.5.96/29141.90.5.97 to 141.90.5.102141.90.5.1036
174141.90.5.104/29141.90.5.105 to 141.90.5.110141.90.5.1116
175141.90.5.112/29141.90.5.113 to 141.90.5.118141.90.5.1196
176141.90.5.120/29141.90.5.121 to 141.90.5.126141.90.5.1276
177141.90.5.128/29141.90.5.129 to 141.90.5.134141.90.5.1356
178141.90.5.136/29141.90.5.137 to 141.90.5.142141.90.5.1436
179141.90.5.144/29141.90.5.145 to 141.90.5.150141.90.5.1516
180141.90.5.152/29141.90.5.153 to 141.90.5.158141.90.5.1596
181141.90.5.160/29141.90.5.161 to 141.90.5.166141.90.5.1676
182141.90.5.168/29141.90.5.169 to 141.90.5.174141.90.5.1756
183141.90.5.176/29141.90.5.177 to 141.90.5.182141.90.5.1836
184141.90.5.184/29141.90.5.185 to 141.90.5.190141.90.5.1916
185141.90.5.192/29141.90.5.193 to 141.90.5.198141.90.5.1996
186141.90.5.200/29141.90.5.201 to 141.90.5.206141.90.5.2076
187141.90.5.208/29141.90.5.209 to 141.90.5.214141.90.5.2156
188141.90.5.216/29141.90.5.217 to 141.90.5.222141.90.5.2236
189141.90.5.224/29141.90.5.225 to 141.90.5.230141.90.5.2316
190141.90.5.232/29141.90.5.233 to 141.90.5.238141.90.5.2396
191141.90.5.240/29141.90.5.241 to 141.90.5.246141.90.5.2476
192141.90.5.248/29141.90.5.249 to 141.90.5.254141.90.5.2556
193141.90.6.0/29141.90.6.1 to 141.90.6.6141.90.6.76
194141.90.6.8/29141.90.6.9 to 141.90.6.14141.90.6.156
195141.90.6.16/29141.90.6.17 to 141.90.6.22141.90.6.236
196141.90.6.24/29141.90.6.25 to 141.90.6.30141.90.6.316
197141.90.6.32/29141.90.6.33 to 141.90.6.38141.90.6.396
198141.90.6.40/29141.90.6.41 to 141.90.6.46141.90.6.476
199141.90.6.48/29141.90.6.49 to 141.90.6.54141.90.6.556
200141.90.6.56/29141.90.6.57 to 141.90.6.62141.90.6.636
201141.90.6.64/29141.90.6.65 to 141.90.6.70141.90.6.716
202141.90.6.72/29141.90.6.73 to 141.90.6.78141.90.6.796
203141.90.6.80/29141.90.6.81 to 141.90.6.86141.90.6.876
204141.90.6.88/29141.90.6.89 to 141.90.6.94141.90.6.956
205141.90.6.96/29141.90.6.97 to 141.90.6.102141.90.6.1036
206141.90.6.104/29141.90.6.105 to 141.90.6.110141.90.6.1116
207141.90.6.112/29141.90.6.113 to 141.90.6.118141.90.6.1196
208141.90.6.120/29141.90.6.121 to 141.90.6.126141.90.6.1276
209141.90.6.128/29141.90.6.129 to 141.90.6.134141.90.6.1356
210141.90.6.136/29141.90.6.137 to 141.90.6.142141.90.6.1436
211141.90.6.144/29141.90.6.145 to 141.90.6.150141.90.6.1516
212141.90.6.152/29141.90.6.153 to 141.90.6.158141.90.6.1596
213141.90.6.160/29141.90.6.161 to 141.90.6.166141.90.6.1676
214141.90.6.168/29141.90.6.169 to 141.90.6.174141.90.6.1756
215141.90.6.176/29141.90.6.177 to 141.90.6.182141.90.6.1836
216141.90.6.184/29141.90.6.185 to 141.90.6.190141.90.6.1916
217141.90.6.192/29141.90.6.193 to 141.90.6.198141.90.6.1996
218141.90.6.200/29141.90.6.201 to 141.90.6.206141.90.6.2076
219141.90.6.208/29141.90.6.209 to 141.90.6.214141.90.6.2156
220141.90.6.216/29141.90.6.217 to 141.90.6.222141.90.6.2236
221141.90.6.224/29141.90.6.225 to 141.90.6.230141.90.6.2316
222141.90.6.232/29141.90.6.233 to 141.90.6.238141.90.6.2396
223141.90.6.240/29141.90.6.241 to 141.90.6.246141.90.6.2476
224141.90.6.248/29141.90.6.249 to 141.90.6.254141.90.6.2556
225141.90.7.0/29141.90.7.1 to 141.90.7.6141.90.7.76
226141.90.7.8/29141.90.7.9 to 141.90.7.14141.90.7.156
227141.90.7.16/29141.90.7.17 to 141.90.7.22141.90.7.236
228141.90.7.24/29141.90.7.25 to 141.90.7.30141.90.7.316
229141.90.7.32/29141.90.7.33 to 141.90.7.38141.90.7.396
230141.90.7.40/29141.90.7.41 to 141.90.7.46141.90.7.476
231141.90.7.48/29141.90.7.49 to 141.90.7.54141.90.7.556
232141.90.7.56/29141.90.7.57 to 141.90.7.62141.90.7.636
233141.90.7.64/29141.90.7.65 to 141.90.7.70141.90.7.716
234141.90.7.72/29141.90.7.73 to 141.90.7.78141.90.7.796
235141.90.7.80/29141.90.7.81 to 141.90.7.86141.90.7.876
236141.90.7.88/29141.90.7.89 to 141.90.7.94141.90.7.956
237141.90.7.96/29141.90.7.97 to 141.90.7.102141.90.7.1036
238141.90.7.104/29141.90.7.105 to 141.90.7.110141.90.7.1116
239141.90.7.112/29141.90.7.113 to 141.90.7.118141.90.7.1196
240141.90.7.120/29141.90.7.121 to 141.90.7.126141.90.7.1276
241141.90.7.128/29141.90.7.129 to 141.90.7.134141.90.7.1356
242141.90.7.136/29141.90.7.137 to 141.90.7.142141.90.7.1436
243141.90.7.144/29141.90.7.145 to 141.90.7.150141.90.7.1516
244141.90.7.152/29141.90.7.153 to 141.90.7.158141.90.7.1596
245141.90.7.160/29141.90.7.161 to 141.90.7.166141.90.7.1676
246141.90.7.168/29141.90.7.169 to 141.90.7.174141.90.7.1756
247141.90.7.176/29141.90.7.177 to 141.90.7.182141.90.7.1836
248141.90.7.184/29141.90.7.185 to 141.90.7.190141.90.7.1916
249141.90.7.192/29141.90.7.193 to 141.90.7.198141.90.7.1996
250141.90.7.200/29141.90.7.201 to 141.90.7.206141.90.7.2076
251141.90.7.208/29141.90.7.209 to 141.90.7.214141.90.7.2156
252141.90.7.216/29141.90.7.217 to 141.90.7.222141.90.7.2236
253141.90.7.224/29141.90.7.225 to 141.90.7.230141.90.7.2316
254141.90.7.232/29141.90.7.233 to 141.90.7.238141.90.7.2396
255141.90.7.240/29141.90.7.241 to 141.90.7.246141.90.7.2476
256141.90.7.248/29141.90.7.249 to 141.90.7.254141.90.7.2556

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