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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.

Network199.2.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
199.2.0.0
Broadcast address
199.2.255.255
First usable
199.2.0.1
Last usable
199.2.255.254
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
Public public
Old class
C (default /24)
As numbers
Hex C7020000 · Integer 3338797056 to 3338862591
Reverse DNS zone
2.199.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11000111.00000010..00000000.00000000199.2.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network11000111.00000010..00000000.00000000199.2.0.0
Broadcast11000111.00000010..11111111.11111111199.2.255.255
Split into smaller subnets/28

199.2.0.0/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1199.2.0.0/28199.2.0.1 to 199.2.0.14199.2.0.1514
2199.2.0.16/28199.2.0.17 to 199.2.0.30199.2.0.3114
3199.2.0.32/28199.2.0.33 to 199.2.0.46199.2.0.4714
4199.2.0.48/28199.2.0.49 to 199.2.0.62199.2.0.6314
5199.2.0.64/28199.2.0.65 to 199.2.0.78199.2.0.7914
6199.2.0.80/28199.2.0.81 to 199.2.0.94199.2.0.9514
7199.2.0.96/28199.2.0.97 to 199.2.0.110199.2.0.11114
8199.2.0.112/28199.2.0.113 to 199.2.0.126199.2.0.12714
9199.2.0.128/28199.2.0.129 to 199.2.0.142199.2.0.14314
10199.2.0.144/28199.2.0.145 to 199.2.0.158199.2.0.15914
11199.2.0.160/28199.2.0.161 to 199.2.0.174199.2.0.17514
12199.2.0.176/28199.2.0.177 to 199.2.0.190199.2.0.19114
13199.2.0.192/28199.2.0.193 to 199.2.0.206199.2.0.20714
14199.2.0.208/28199.2.0.209 to 199.2.0.222199.2.0.22314
15199.2.0.224/28199.2.0.225 to 199.2.0.238199.2.0.23914
16199.2.0.240/28199.2.0.241 to 199.2.0.254199.2.0.25514
17199.2.1.0/28199.2.1.1 to 199.2.1.14199.2.1.1514
18199.2.1.16/28199.2.1.17 to 199.2.1.30199.2.1.3114
19199.2.1.32/28199.2.1.33 to 199.2.1.46199.2.1.4714
20199.2.1.48/28199.2.1.49 to 199.2.1.62199.2.1.6314
21199.2.1.64/28199.2.1.65 to 199.2.1.78199.2.1.7914
22199.2.1.80/28199.2.1.81 to 199.2.1.94199.2.1.9514
23199.2.1.96/28199.2.1.97 to 199.2.1.110199.2.1.11114
24199.2.1.112/28199.2.1.113 to 199.2.1.126199.2.1.12714
25199.2.1.128/28199.2.1.129 to 199.2.1.142199.2.1.14314
26199.2.1.144/28199.2.1.145 to 199.2.1.158199.2.1.15914
27199.2.1.160/28199.2.1.161 to 199.2.1.174199.2.1.17514
28199.2.1.176/28199.2.1.177 to 199.2.1.190199.2.1.19114
29199.2.1.192/28199.2.1.193 to 199.2.1.206199.2.1.20714
30199.2.1.208/28199.2.1.209 to 199.2.1.222199.2.1.22314
31199.2.1.224/28199.2.1.225 to 199.2.1.238199.2.1.23914
32199.2.1.240/28199.2.1.241 to 199.2.1.254199.2.1.25514
33199.2.2.0/28199.2.2.1 to 199.2.2.14199.2.2.1514
34199.2.2.16/28199.2.2.17 to 199.2.2.30199.2.2.3114
35199.2.2.32/28199.2.2.33 to 199.2.2.46199.2.2.4714
36199.2.2.48/28199.2.2.49 to 199.2.2.62199.2.2.6314
37199.2.2.64/28199.2.2.65 to 199.2.2.78199.2.2.7914
38199.2.2.80/28199.2.2.81 to 199.2.2.94199.2.2.9514
39199.2.2.96/28199.2.2.97 to 199.2.2.110199.2.2.11114
40199.2.2.112/28199.2.2.113 to 199.2.2.126199.2.2.12714
41199.2.2.128/28199.2.2.129 to 199.2.2.142199.2.2.14314
42199.2.2.144/28199.2.2.145 to 199.2.2.158199.2.2.15914
43199.2.2.160/28199.2.2.161 to 199.2.2.174199.2.2.17514
44199.2.2.176/28199.2.2.177 to 199.2.2.190199.2.2.19114
45199.2.2.192/28199.2.2.193 to 199.2.2.206199.2.2.20714
46199.2.2.208/28199.2.2.209 to 199.2.2.222199.2.2.22314
47199.2.2.224/28199.2.2.225 to 199.2.2.238199.2.2.23914
48199.2.2.240/28199.2.2.241 to 199.2.2.254199.2.2.25514
49199.2.3.0/28199.2.3.1 to 199.2.3.14199.2.3.1514
50199.2.3.16/28199.2.3.17 to 199.2.3.30199.2.3.3114
51199.2.3.32/28199.2.3.33 to 199.2.3.46199.2.3.4714
52199.2.3.48/28199.2.3.49 to 199.2.3.62199.2.3.6314
53199.2.3.64/28199.2.3.65 to 199.2.3.78199.2.3.7914
54199.2.3.80/28199.2.3.81 to 199.2.3.94199.2.3.9514
55199.2.3.96/28199.2.3.97 to 199.2.3.110199.2.3.11114
56199.2.3.112/28199.2.3.113 to 199.2.3.126199.2.3.12714
57199.2.3.128/28199.2.3.129 to 199.2.3.142199.2.3.14314
58199.2.3.144/28199.2.3.145 to 199.2.3.158199.2.3.15914
59199.2.3.160/28199.2.3.161 to 199.2.3.174199.2.3.17514
60199.2.3.176/28199.2.3.177 to 199.2.3.190199.2.3.19114
61199.2.3.192/28199.2.3.193 to 199.2.3.206199.2.3.20714
62199.2.3.208/28199.2.3.209 to 199.2.3.222199.2.3.22314
63199.2.3.224/28199.2.3.225 to 199.2.3.238199.2.3.23914
64199.2.3.240/28199.2.3.241 to 199.2.3.254199.2.3.25514
65199.2.4.0/28199.2.4.1 to 199.2.4.14199.2.4.1514
66199.2.4.16/28199.2.4.17 to 199.2.4.30199.2.4.3114
67199.2.4.32/28199.2.4.33 to 199.2.4.46199.2.4.4714
68199.2.4.48/28199.2.4.49 to 199.2.4.62199.2.4.6314
69199.2.4.64/28199.2.4.65 to 199.2.4.78199.2.4.7914
70199.2.4.80/28199.2.4.81 to 199.2.4.94199.2.4.9514
71199.2.4.96/28199.2.4.97 to 199.2.4.110199.2.4.11114
72199.2.4.112/28199.2.4.113 to 199.2.4.126199.2.4.12714
73199.2.4.128/28199.2.4.129 to 199.2.4.142199.2.4.14314
74199.2.4.144/28199.2.4.145 to 199.2.4.158199.2.4.15914
75199.2.4.160/28199.2.4.161 to 199.2.4.174199.2.4.17514
76199.2.4.176/28199.2.4.177 to 199.2.4.190199.2.4.19114
77199.2.4.192/28199.2.4.193 to 199.2.4.206199.2.4.20714
78199.2.4.208/28199.2.4.209 to 199.2.4.222199.2.4.22314
79199.2.4.224/28199.2.4.225 to 199.2.4.238199.2.4.23914
80199.2.4.240/28199.2.4.241 to 199.2.4.254199.2.4.25514
81199.2.5.0/28199.2.5.1 to 199.2.5.14199.2.5.1514
82199.2.5.16/28199.2.5.17 to 199.2.5.30199.2.5.3114
83199.2.5.32/28199.2.5.33 to 199.2.5.46199.2.5.4714
84199.2.5.48/28199.2.5.49 to 199.2.5.62199.2.5.6314
85199.2.5.64/28199.2.5.65 to 199.2.5.78199.2.5.7914
86199.2.5.80/28199.2.5.81 to 199.2.5.94199.2.5.9514
87199.2.5.96/28199.2.5.97 to 199.2.5.110199.2.5.11114
88199.2.5.112/28199.2.5.113 to 199.2.5.126199.2.5.12714
89199.2.5.128/28199.2.5.129 to 199.2.5.142199.2.5.14314
90199.2.5.144/28199.2.5.145 to 199.2.5.158199.2.5.15914
91199.2.5.160/28199.2.5.161 to 199.2.5.174199.2.5.17514
92199.2.5.176/28199.2.5.177 to 199.2.5.190199.2.5.19114
93199.2.5.192/28199.2.5.193 to 199.2.5.206199.2.5.20714
94199.2.5.208/28199.2.5.209 to 199.2.5.222199.2.5.22314
95199.2.5.224/28199.2.5.225 to 199.2.5.238199.2.5.23914
96199.2.5.240/28199.2.5.241 to 199.2.5.254199.2.5.25514
97199.2.6.0/28199.2.6.1 to 199.2.6.14199.2.6.1514
98199.2.6.16/28199.2.6.17 to 199.2.6.30199.2.6.3114
99199.2.6.32/28199.2.6.33 to 199.2.6.46199.2.6.4714
100199.2.6.48/28199.2.6.49 to 199.2.6.62199.2.6.6314
101199.2.6.64/28199.2.6.65 to 199.2.6.78199.2.6.7914
102199.2.6.80/28199.2.6.81 to 199.2.6.94199.2.6.9514
103199.2.6.96/28199.2.6.97 to 199.2.6.110199.2.6.11114
104199.2.6.112/28199.2.6.113 to 199.2.6.126199.2.6.12714
105199.2.6.128/28199.2.6.129 to 199.2.6.142199.2.6.14314
106199.2.6.144/28199.2.6.145 to 199.2.6.158199.2.6.15914
107199.2.6.160/28199.2.6.161 to 199.2.6.174199.2.6.17514
108199.2.6.176/28199.2.6.177 to 199.2.6.190199.2.6.19114
109199.2.6.192/28199.2.6.193 to 199.2.6.206199.2.6.20714
110199.2.6.208/28199.2.6.209 to 199.2.6.222199.2.6.22314
111199.2.6.224/28199.2.6.225 to 199.2.6.238199.2.6.23914
112199.2.6.240/28199.2.6.241 to 199.2.6.254199.2.6.25514
113199.2.7.0/28199.2.7.1 to 199.2.7.14199.2.7.1514
114199.2.7.16/28199.2.7.17 to 199.2.7.30199.2.7.3114
115199.2.7.32/28199.2.7.33 to 199.2.7.46199.2.7.4714
116199.2.7.48/28199.2.7.49 to 199.2.7.62199.2.7.6314
117199.2.7.64/28199.2.7.65 to 199.2.7.78199.2.7.7914
118199.2.7.80/28199.2.7.81 to 199.2.7.94199.2.7.9514
119199.2.7.96/28199.2.7.97 to 199.2.7.110199.2.7.11114
120199.2.7.112/28199.2.7.113 to 199.2.7.126199.2.7.12714
121199.2.7.128/28199.2.7.129 to 199.2.7.142199.2.7.14314
122199.2.7.144/28199.2.7.145 to 199.2.7.158199.2.7.15914
123199.2.7.160/28199.2.7.161 to 199.2.7.174199.2.7.17514
124199.2.7.176/28199.2.7.177 to 199.2.7.190199.2.7.19114
125199.2.7.192/28199.2.7.193 to 199.2.7.206199.2.7.20714
126199.2.7.208/28199.2.7.209 to 199.2.7.222199.2.7.22314
127199.2.7.224/28199.2.7.225 to 199.2.7.238199.2.7.23914
128199.2.7.240/28199.2.7.241 to 199.2.7.254199.2.7.25514
129199.2.8.0/28199.2.8.1 to 199.2.8.14199.2.8.1514
130199.2.8.16/28199.2.8.17 to 199.2.8.30199.2.8.3114
131199.2.8.32/28199.2.8.33 to 199.2.8.46199.2.8.4714
132199.2.8.48/28199.2.8.49 to 199.2.8.62199.2.8.6314
133199.2.8.64/28199.2.8.65 to 199.2.8.78199.2.8.7914
134199.2.8.80/28199.2.8.81 to 199.2.8.94199.2.8.9514
135199.2.8.96/28199.2.8.97 to 199.2.8.110199.2.8.11114
136199.2.8.112/28199.2.8.113 to 199.2.8.126199.2.8.12714
137199.2.8.128/28199.2.8.129 to 199.2.8.142199.2.8.14314
138199.2.8.144/28199.2.8.145 to 199.2.8.158199.2.8.15914
139199.2.8.160/28199.2.8.161 to 199.2.8.174199.2.8.17514
140199.2.8.176/28199.2.8.177 to 199.2.8.190199.2.8.19114
141199.2.8.192/28199.2.8.193 to 199.2.8.206199.2.8.20714
142199.2.8.208/28199.2.8.209 to 199.2.8.222199.2.8.22314
143199.2.8.224/28199.2.8.225 to 199.2.8.238199.2.8.23914
144199.2.8.240/28199.2.8.241 to 199.2.8.254199.2.8.25514
145199.2.9.0/28199.2.9.1 to 199.2.9.14199.2.9.1514
146199.2.9.16/28199.2.9.17 to 199.2.9.30199.2.9.3114
147199.2.9.32/28199.2.9.33 to 199.2.9.46199.2.9.4714
148199.2.9.48/28199.2.9.49 to 199.2.9.62199.2.9.6314
149199.2.9.64/28199.2.9.65 to 199.2.9.78199.2.9.7914
150199.2.9.80/28199.2.9.81 to 199.2.9.94199.2.9.9514
151199.2.9.96/28199.2.9.97 to 199.2.9.110199.2.9.11114
152199.2.9.112/28199.2.9.113 to 199.2.9.126199.2.9.12714
153199.2.9.128/28199.2.9.129 to 199.2.9.142199.2.9.14314
154199.2.9.144/28199.2.9.145 to 199.2.9.158199.2.9.15914
155199.2.9.160/28199.2.9.161 to 199.2.9.174199.2.9.17514
156199.2.9.176/28199.2.9.177 to 199.2.9.190199.2.9.19114
157199.2.9.192/28199.2.9.193 to 199.2.9.206199.2.9.20714
158199.2.9.208/28199.2.9.209 to 199.2.9.222199.2.9.22314
159199.2.9.224/28199.2.9.225 to 199.2.9.238199.2.9.23914
160199.2.9.240/28199.2.9.241 to 199.2.9.254199.2.9.25514
161199.2.10.0/28199.2.10.1 to 199.2.10.14199.2.10.1514
162199.2.10.16/28199.2.10.17 to 199.2.10.30199.2.10.3114
163199.2.10.32/28199.2.10.33 to 199.2.10.46199.2.10.4714
164199.2.10.48/28199.2.10.49 to 199.2.10.62199.2.10.6314
165199.2.10.64/28199.2.10.65 to 199.2.10.78199.2.10.7914
166199.2.10.80/28199.2.10.81 to 199.2.10.94199.2.10.9514
167199.2.10.96/28199.2.10.97 to 199.2.10.110199.2.10.11114
168199.2.10.112/28199.2.10.113 to 199.2.10.126199.2.10.12714
169199.2.10.128/28199.2.10.129 to 199.2.10.142199.2.10.14314
170199.2.10.144/28199.2.10.145 to 199.2.10.158199.2.10.15914
171199.2.10.160/28199.2.10.161 to 199.2.10.174199.2.10.17514
172199.2.10.176/28199.2.10.177 to 199.2.10.190199.2.10.19114
173199.2.10.192/28199.2.10.193 to 199.2.10.206199.2.10.20714
174199.2.10.208/28199.2.10.209 to 199.2.10.222199.2.10.22314
175199.2.10.224/28199.2.10.225 to 199.2.10.238199.2.10.23914
176199.2.10.240/28199.2.10.241 to 199.2.10.254199.2.10.25514
177199.2.11.0/28199.2.11.1 to 199.2.11.14199.2.11.1514
178199.2.11.16/28199.2.11.17 to 199.2.11.30199.2.11.3114
179199.2.11.32/28199.2.11.33 to 199.2.11.46199.2.11.4714
180199.2.11.48/28199.2.11.49 to 199.2.11.62199.2.11.6314
181199.2.11.64/28199.2.11.65 to 199.2.11.78199.2.11.7914
182199.2.11.80/28199.2.11.81 to 199.2.11.94199.2.11.9514
183199.2.11.96/28199.2.11.97 to 199.2.11.110199.2.11.11114
184199.2.11.112/28199.2.11.113 to 199.2.11.126199.2.11.12714
185199.2.11.128/28199.2.11.129 to 199.2.11.142199.2.11.14314
186199.2.11.144/28199.2.11.145 to 199.2.11.158199.2.11.15914
187199.2.11.160/28199.2.11.161 to 199.2.11.174199.2.11.17514
188199.2.11.176/28199.2.11.177 to 199.2.11.190199.2.11.19114
189199.2.11.192/28199.2.11.193 to 199.2.11.206199.2.11.20714
190199.2.11.208/28199.2.11.209 to 199.2.11.222199.2.11.22314
191199.2.11.224/28199.2.11.225 to 199.2.11.238199.2.11.23914
192199.2.11.240/28199.2.11.241 to 199.2.11.254199.2.11.25514
193199.2.12.0/28199.2.12.1 to 199.2.12.14199.2.12.1514
194199.2.12.16/28199.2.12.17 to 199.2.12.30199.2.12.3114
195199.2.12.32/28199.2.12.33 to 199.2.12.46199.2.12.4714
196199.2.12.48/28199.2.12.49 to 199.2.12.62199.2.12.6314
197199.2.12.64/28199.2.12.65 to 199.2.12.78199.2.12.7914
198199.2.12.80/28199.2.12.81 to 199.2.12.94199.2.12.9514
199199.2.12.96/28199.2.12.97 to 199.2.12.110199.2.12.11114
200199.2.12.112/28199.2.12.113 to 199.2.12.126199.2.12.12714
201199.2.12.128/28199.2.12.129 to 199.2.12.142199.2.12.14314
202199.2.12.144/28199.2.12.145 to 199.2.12.158199.2.12.15914
203199.2.12.160/28199.2.12.161 to 199.2.12.174199.2.12.17514
204199.2.12.176/28199.2.12.177 to 199.2.12.190199.2.12.19114
205199.2.12.192/28199.2.12.193 to 199.2.12.206199.2.12.20714
206199.2.12.208/28199.2.12.209 to 199.2.12.222199.2.12.22314
207199.2.12.224/28199.2.12.225 to 199.2.12.238199.2.12.23914
208199.2.12.240/28199.2.12.241 to 199.2.12.254199.2.12.25514
209199.2.13.0/28199.2.13.1 to 199.2.13.14199.2.13.1514
210199.2.13.16/28199.2.13.17 to 199.2.13.30199.2.13.3114
211199.2.13.32/28199.2.13.33 to 199.2.13.46199.2.13.4714
212199.2.13.48/28199.2.13.49 to 199.2.13.62199.2.13.6314
213199.2.13.64/28199.2.13.65 to 199.2.13.78199.2.13.7914
214199.2.13.80/28199.2.13.81 to 199.2.13.94199.2.13.9514
215199.2.13.96/28199.2.13.97 to 199.2.13.110199.2.13.11114
216199.2.13.112/28199.2.13.113 to 199.2.13.126199.2.13.12714
217199.2.13.128/28199.2.13.129 to 199.2.13.142199.2.13.14314
218199.2.13.144/28199.2.13.145 to 199.2.13.158199.2.13.15914
219199.2.13.160/28199.2.13.161 to 199.2.13.174199.2.13.17514
220199.2.13.176/28199.2.13.177 to 199.2.13.190199.2.13.19114
221199.2.13.192/28199.2.13.193 to 199.2.13.206199.2.13.20714
222199.2.13.208/28199.2.13.209 to 199.2.13.222199.2.13.22314
223199.2.13.224/28199.2.13.225 to 199.2.13.238199.2.13.23914
224199.2.13.240/28199.2.13.241 to 199.2.13.254199.2.13.25514
225199.2.14.0/28199.2.14.1 to 199.2.14.14199.2.14.1514
226199.2.14.16/28199.2.14.17 to 199.2.14.30199.2.14.3114
227199.2.14.32/28199.2.14.33 to 199.2.14.46199.2.14.4714
228199.2.14.48/28199.2.14.49 to 199.2.14.62199.2.14.6314
229199.2.14.64/28199.2.14.65 to 199.2.14.78199.2.14.7914
230199.2.14.80/28199.2.14.81 to 199.2.14.94199.2.14.9514
231199.2.14.96/28199.2.14.97 to 199.2.14.110199.2.14.11114
232199.2.14.112/28199.2.14.113 to 199.2.14.126199.2.14.12714
233199.2.14.128/28199.2.14.129 to 199.2.14.142199.2.14.14314
234199.2.14.144/28199.2.14.145 to 199.2.14.158199.2.14.15914
235199.2.14.160/28199.2.14.161 to 199.2.14.174199.2.14.17514
236199.2.14.176/28199.2.14.177 to 199.2.14.190199.2.14.19114
237199.2.14.192/28199.2.14.193 to 199.2.14.206199.2.14.20714
238199.2.14.208/28199.2.14.209 to 199.2.14.222199.2.14.22314
239199.2.14.224/28199.2.14.225 to 199.2.14.238199.2.14.23914
240199.2.14.240/28199.2.14.241 to 199.2.14.254199.2.14.25514
241199.2.15.0/28199.2.15.1 to 199.2.15.14199.2.15.1514
242199.2.15.16/28199.2.15.17 to 199.2.15.30199.2.15.3114
243199.2.15.32/28199.2.15.33 to 199.2.15.46199.2.15.4714
244199.2.15.48/28199.2.15.49 to 199.2.15.62199.2.15.6314
245199.2.15.64/28199.2.15.65 to 199.2.15.78199.2.15.7914
246199.2.15.80/28199.2.15.81 to 199.2.15.94199.2.15.9514
247199.2.15.96/28199.2.15.97 to 199.2.15.110199.2.15.11114
248199.2.15.112/28199.2.15.113 to 199.2.15.126199.2.15.12714
249199.2.15.128/28199.2.15.129 to 199.2.15.142199.2.15.14314
250199.2.15.144/28199.2.15.145 to 199.2.15.158199.2.15.15914
251199.2.15.160/28199.2.15.161 to 199.2.15.174199.2.15.17514
252199.2.15.176/28199.2.15.177 to 199.2.15.190199.2.15.19114
253199.2.15.192/28199.2.15.193 to 199.2.15.206199.2.15.20714
254199.2.15.208/28199.2.15.209 to 199.2.15.222199.2.15.22314
255199.2.15.224/28199.2.15.225 to 199.2.15.238199.2.15.23914
256199.2.15.240/28199.2.15.241 to 199.2.15.254199.2.15.25514

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