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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.

Network174.26.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
174.26.0.0
Broadcast address
174.27.255.255
First usable
174.26.0.1
Last usable
174.27.255.254
Usable hosts
131,070 (131,072 less the network and broadcast addresses)
Subnet mask
255.254.0.0
Wildcard mask
0.1.255.255 (Cisco ACLs, OSPF)
Prefix length
/15
Type
Public public
Old class
B (default /16)
As numbers
Hex AE1A0000 · Integer 2920939520 to 2921070591
Reverse DNS zones
26.174.in-addr.arpa
27.174.in-addr.arpa
/15 is not on a 8-bit boundary, so it takes 2 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10101110.00011010.00000000.00000000174.26.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network10101110.00011010.00000000.00000000174.26.0.0
Broadcast10101110.00011011.11111111.11111111174.27.255.255
Split into smaller subnets/27
/16 (2)/17 (4)/18 (8)/19 (16)/20 (32)/21 (64)/22 (128)/23 (256)/24 (512)/25 (1,024)/26 (2,048)/27 (4,096)

174.26.0.0/15 makes 4,096 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1174.26.0.0/27174.26.0.1 to 174.26.0.30174.26.0.3130
2174.26.0.32/27174.26.0.33 to 174.26.0.62174.26.0.6330
3174.26.0.64/27174.26.0.65 to 174.26.0.94174.26.0.9530
4174.26.0.96/27174.26.0.97 to 174.26.0.126174.26.0.12730
5174.26.0.128/27174.26.0.129 to 174.26.0.158174.26.0.15930
6174.26.0.160/27174.26.0.161 to 174.26.0.190174.26.0.19130
7174.26.0.192/27174.26.0.193 to 174.26.0.222174.26.0.22330
8174.26.0.224/27174.26.0.225 to 174.26.0.254174.26.0.25530
9174.26.1.0/27174.26.1.1 to 174.26.1.30174.26.1.3130
10174.26.1.32/27174.26.1.33 to 174.26.1.62174.26.1.6330
11174.26.1.64/27174.26.1.65 to 174.26.1.94174.26.1.9530
12174.26.1.96/27174.26.1.97 to 174.26.1.126174.26.1.12730
13174.26.1.128/27174.26.1.129 to 174.26.1.158174.26.1.15930
14174.26.1.160/27174.26.1.161 to 174.26.1.190174.26.1.19130
15174.26.1.192/27174.26.1.193 to 174.26.1.222174.26.1.22330
16174.26.1.224/27174.26.1.225 to 174.26.1.254174.26.1.25530
17174.26.2.0/27174.26.2.1 to 174.26.2.30174.26.2.3130
18174.26.2.32/27174.26.2.33 to 174.26.2.62174.26.2.6330
19174.26.2.64/27174.26.2.65 to 174.26.2.94174.26.2.9530
20174.26.2.96/27174.26.2.97 to 174.26.2.126174.26.2.12730
21174.26.2.128/27174.26.2.129 to 174.26.2.158174.26.2.15930
22174.26.2.160/27174.26.2.161 to 174.26.2.190174.26.2.19130
23174.26.2.192/27174.26.2.193 to 174.26.2.222174.26.2.22330
24174.26.2.224/27174.26.2.225 to 174.26.2.254174.26.2.25530
25174.26.3.0/27174.26.3.1 to 174.26.3.30174.26.3.3130
26174.26.3.32/27174.26.3.33 to 174.26.3.62174.26.3.6330
27174.26.3.64/27174.26.3.65 to 174.26.3.94174.26.3.9530
28174.26.3.96/27174.26.3.97 to 174.26.3.126174.26.3.12730
29174.26.3.128/27174.26.3.129 to 174.26.3.158174.26.3.15930
30174.26.3.160/27174.26.3.161 to 174.26.3.190174.26.3.19130
31174.26.3.192/27174.26.3.193 to 174.26.3.222174.26.3.22330
32174.26.3.224/27174.26.3.225 to 174.26.3.254174.26.3.25530
33174.26.4.0/27174.26.4.1 to 174.26.4.30174.26.4.3130
34174.26.4.32/27174.26.4.33 to 174.26.4.62174.26.4.6330
35174.26.4.64/27174.26.4.65 to 174.26.4.94174.26.4.9530
36174.26.4.96/27174.26.4.97 to 174.26.4.126174.26.4.12730
37174.26.4.128/27174.26.4.129 to 174.26.4.158174.26.4.15930
38174.26.4.160/27174.26.4.161 to 174.26.4.190174.26.4.19130
39174.26.4.192/27174.26.4.193 to 174.26.4.222174.26.4.22330
40174.26.4.224/27174.26.4.225 to 174.26.4.254174.26.4.25530
41174.26.5.0/27174.26.5.1 to 174.26.5.30174.26.5.3130
42174.26.5.32/27174.26.5.33 to 174.26.5.62174.26.5.6330
43174.26.5.64/27174.26.5.65 to 174.26.5.94174.26.5.9530
44174.26.5.96/27174.26.5.97 to 174.26.5.126174.26.5.12730
45174.26.5.128/27174.26.5.129 to 174.26.5.158174.26.5.15930
46174.26.5.160/27174.26.5.161 to 174.26.5.190174.26.5.19130
47174.26.5.192/27174.26.5.193 to 174.26.5.222174.26.5.22330
48174.26.5.224/27174.26.5.225 to 174.26.5.254174.26.5.25530
49174.26.6.0/27174.26.6.1 to 174.26.6.30174.26.6.3130
50174.26.6.32/27174.26.6.33 to 174.26.6.62174.26.6.6330
51174.26.6.64/27174.26.6.65 to 174.26.6.94174.26.6.9530
52174.26.6.96/27174.26.6.97 to 174.26.6.126174.26.6.12730
53174.26.6.128/27174.26.6.129 to 174.26.6.158174.26.6.15930
54174.26.6.160/27174.26.6.161 to 174.26.6.190174.26.6.19130
55174.26.6.192/27174.26.6.193 to 174.26.6.222174.26.6.22330
56174.26.6.224/27174.26.6.225 to 174.26.6.254174.26.6.25530
57174.26.7.0/27174.26.7.1 to 174.26.7.30174.26.7.3130
58174.26.7.32/27174.26.7.33 to 174.26.7.62174.26.7.6330
59174.26.7.64/27174.26.7.65 to 174.26.7.94174.26.7.9530
60174.26.7.96/27174.26.7.97 to 174.26.7.126174.26.7.12730
61174.26.7.128/27174.26.7.129 to 174.26.7.158174.26.7.15930
62174.26.7.160/27174.26.7.161 to 174.26.7.190174.26.7.19130
63174.26.7.192/27174.26.7.193 to 174.26.7.222174.26.7.22330
64174.26.7.224/27174.26.7.225 to 174.26.7.254174.26.7.25530
65174.26.8.0/27174.26.8.1 to 174.26.8.30174.26.8.3130
66174.26.8.32/27174.26.8.33 to 174.26.8.62174.26.8.6330
67174.26.8.64/27174.26.8.65 to 174.26.8.94174.26.8.9530
68174.26.8.96/27174.26.8.97 to 174.26.8.126174.26.8.12730
69174.26.8.128/27174.26.8.129 to 174.26.8.158174.26.8.15930
70174.26.8.160/27174.26.8.161 to 174.26.8.190174.26.8.19130
71174.26.8.192/27174.26.8.193 to 174.26.8.222174.26.8.22330
72174.26.8.224/27174.26.8.225 to 174.26.8.254174.26.8.25530
73174.26.9.0/27174.26.9.1 to 174.26.9.30174.26.9.3130
74174.26.9.32/27174.26.9.33 to 174.26.9.62174.26.9.6330
75174.26.9.64/27174.26.9.65 to 174.26.9.94174.26.9.9530
76174.26.9.96/27174.26.9.97 to 174.26.9.126174.26.9.12730
77174.26.9.128/27174.26.9.129 to 174.26.9.158174.26.9.15930
78174.26.9.160/27174.26.9.161 to 174.26.9.190174.26.9.19130
79174.26.9.192/27174.26.9.193 to 174.26.9.222174.26.9.22330
80174.26.9.224/27174.26.9.225 to 174.26.9.254174.26.9.25530
81174.26.10.0/27174.26.10.1 to 174.26.10.30174.26.10.3130
82174.26.10.32/27174.26.10.33 to 174.26.10.62174.26.10.6330
83174.26.10.64/27174.26.10.65 to 174.26.10.94174.26.10.9530
84174.26.10.96/27174.26.10.97 to 174.26.10.126174.26.10.12730
85174.26.10.128/27174.26.10.129 to 174.26.10.158174.26.10.15930
86174.26.10.160/27174.26.10.161 to 174.26.10.190174.26.10.19130
87174.26.10.192/27174.26.10.193 to 174.26.10.222174.26.10.22330
88174.26.10.224/27174.26.10.225 to 174.26.10.254174.26.10.25530
89174.26.11.0/27174.26.11.1 to 174.26.11.30174.26.11.3130
90174.26.11.32/27174.26.11.33 to 174.26.11.62174.26.11.6330
91174.26.11.64/27174.26.11.65 to 174.26.11.94174.26.11.9530
92174.26.11.96/27174.26.11.97 to 174.26.11.126174.26.11.12730
93174.26.11.128/27174.26.11.129 to 174.26.11.158174.26.11.15930
94174.26.11.160/27174.26.11.161 to 174.26.11.190174.26.11.19130
95174.26.11.192/27174.26.11.193 to 174.26.11.222174.26.11.22330
96174.26.11.224/27174.26.11.225 to 174.26.11.254174.26.11.25530
97174.26.12.0/27174.26.12.1 to 174.26.12.30174.26.12.3130
98174.26.12.32/27174.26.12.33 to 174.26.12.62174.26.12.6330
99174.26.12.64/27174.26.12.65 to 174.26.12.94174.26.12.9530
100174.26.12.96/27174.26.12.97 to 174.26.12.126174.26.12.12730
101174.26.12.128/27174.26.12.129 to 174.26.12.158174.26.12.15930
102174.26.12.160/27174.26.12.161 to 174.26.12.190174.26.12.19130
103174.26.12.192/27174.26.12.193 to 174.26.12.222174.26.12.22330
104174.26.12.224/27174.26.12.225 to 174.26.12.254174.26.12.25530
105174.26.13.0/27174.26.13.1 to 174.26.13.30174.26.13.3130
106174.26.13.32/27174.26.13.33 to 174.26.13.62174.26.13.6330
107174.26.13.64/27174.26.13.65 to 174.26.13.94174.26.13.9530
108174.26.13.96/27174.26.13.97 to 174.26.13.126174.26.13.12730
109174.26.13.128/27174.26.13.129 to 174.26.13.158174.26.13.15930
110174.26.13.160/27174.26.13.161 to 174.26.13.190174.26.13.19130
111174.26.13.192/27174.26.13.193 to 174.26.13.222174.26.13.22330
112174.26.13.224/27174.26.13.225 to 174.26.13.254174.26.13.25530
113174.26.14.0/27174.26.14.1 to 174.26.14.30174.26.14.3130
114174.26.14.32/27174.26.14.33 to 174.26.14.62174.26.14.6330
115174.26.14.64/27174.26.14.65 to 174.26.14.94174.26.14.9530
116174.26.14.96/27174.26.14.97 to 174.26.14.126174.26.14.12730
117174.26.14.128/27174.26.14.129 to 174.26.14.158174.26.14.15930
118174.26.14.160/27174.26.14.161 to 174.26.14.190174.26.14.19130
119174.26.14.192/27174.26.14.193 to 174.26.14.222174.26.14.22330
120174.26.14.224/27174.26.14.225 to 174.26.14.254174.26.14.25530
121174.26.15.0/27174.26.15.1 to 174.26.15.30174.26.15.3130
122174.26.15.32/27174.26.15.33 to 174.26.15.62174.26.15.6330
123174.26.15.64/27174.26.15.65 to 174.26.15.94174.26.15.9530
124174.26.15.96/27174.26.15.97 to 174.26.15.126174.26.15.12730
125174.26.15.128/27174.26.15.129 to 174.26.15.158174.26.15.15930
126174.26.15.160/27174.26.15.161 to 174.26.15.190174.26.15.19130
127174.26.15.192/27174.26.15.193 to 174.26.15.222174.26.15.22330
128174.26.15.224/27174.26.15.225 to 174.26.15.254174.26.15.25530
129174.26.16.0/27174.26.16.1 to 174.26.16.30174.26.16.3130
130174.26.16.32/27174.26.16.33 to 174.26.16.62174.26.16.6330
131174.26.16.64/27174.26.16.65 to 174.26.16.94174.26.16.9530
132174.26.16.96/27174.26.16.97 to 174.26.16.126174.26.16.12730
133174.26.16.128/27174.26.16.129 to 174.26.16.158174.26.16.15930
134174.26.16.160/27174.26.16.161 to 174.26.16.190174.26.16.19130
135174.26.16.192/27174.26.16.193 to 174.26.16.222174.26.16.22330
136174.26.16.224/27174.26.16.225 to 174.26.16.254174.26.16.25530
137174.26.17.0/27174.26.17.1 to 174.26.17.30174.26.17.3130
138174.26.17.32/27174.26.17.33 to 174.26.17.62174.26.17.6330
139174.26.17.64/27174.26.17.65 to 174.26.17.94174.26.17.9530
140174.26.17.96/27174.26.17.97 to 174.26.17.126174.26.17.12730
141174.26.17.128/27174.26.17.129 to 174.26.17.158174.26.17.15930
142174.26.17.160/27174.26.17.161 to 174.26.17.190174.26.17.19130
143174.26.17.192/27174.26.17.193 to 174.26.17.222174.26.17.22330
144174.26.17.224/27174.26.17.225 to 174.26.17.254174.26.17.25530
145174.26.18.0/27174.26.18.1 to 174.26.18.30174.26.18.3130
146174.26.18.32/27174.26.18.33 to 174.26.18.62174.26.18.6330
147174.26.18.64/27174.26.18.65 to 174.26.18.94174.26.18.9530
148174.26.18.96/27174.26.18.97 to 174.26.18.126174.26.18.12730
149174.26.18.128/27174.26.18.129 to 174.26.18.158174.26.18.15930
150174.26.18.160/27174.26.18.161 to 174.26.18.190174.26.18.19130
151174.26.18.192/27174.26.18.193 to 174.26.18.222174.26.18.22330
152174.26.18.224/27174.26.18.225 to 174.26.18.254174.26.18.25530
153174.26.19.0/27174.26.19.1 to 174.26.19.30174.26.19.3130
154174.26.19.32/27174.26.19.33 to 174.26.19.62174.26.19.6330
155174.26.19.64/27174.26.19.65 to 174.26.19.94174.26.19.9530
156174.26.19.96/27174.26.19.97 to 174.26.19.126174.26.19.12730
157174.26.19.128/27174.26.19.129 to 174.26.19.158174.26.19.15930
158174.26.19.160/27174.26.19.161 to 174.26.19.190174.26.19.19130
159174.26.19.192/27174.26.19.193 to 174.26.19.222174.26.19.22330
160174.26.19.224/27174.26.19.225 to 174.26.19.254174.26.19.25530
161174.26.20.0/27174.26.20.1 to 174.26.20.30174.26.20.3130
162174.26.20.32/27174.26.20.33 to 174.26.20.62174.26.20.6330
163174.26.20.64/27174.26.20.65 to 174.26.20.94174.26.20.9530
164174.26.20.96/27174.26.20.97 to 174.26.20.126174.26.20.12730
165174.26.20.128/27174.26.20.129 to 174.26.20.158174.26.20.15930
166174.26.20.160/27174.26.20.161 to 174.26.20.190174.26.20.19130
167174.26.20.192/27174.26.20.193 to 174.26.20.222174.26.20.22330
168174.26.20.224/27174.26.20.225 to 174.26.20.254174.26.20.25530
169174.26.21.0/27174.26.21.1 to 174.26.21.30174.26.21.3130
170174.26.21.32/27174.26.21.33 to 174.26.21.62174.26.21.6330
171174.26.21.64/27174.26.21.65 to 174.26.21.94174.26.21.9530
172174.26.21.96/27174.26.21.97 to 174.26.21.126174.26.21.12730
173174.26.21.128/27174.26.21.129 to 174.26.21.158174.26.21.15930
174174.26.21.160/27174.26.21.161 to 174.26.21.190174.26.21.19130
175174.26.21.192/27174.26.21.193 to 174.26.21.222174.26.21.22330
176174.26.21.224/27174.26.21.225 to 174.26.21.254174.26.21.25530
177174.26.22.0/27174.26.22.1 to 174.26.22.30174.26.22.3130
178174.26.22.32/27174.26.22.33 to 174.26.22.62174.26.22.6330
179174.26.22.64/27174.26.22.65 to 174.26.22.94174.26.22.9530
180174.26.22.96/27174.26.22.97 to 174.26.22.126174.26.22.12730
181174.26.22.128/27174.26.22.129 to 174.26.22.158174.26.22.15930
182174.26.22.160/27174.26.22.161 to 174.26.22.190174.26.22.19130
183174.26.22.192/27174.26.22.193 to 174.26.22.222174.26.22.22330
184174.26.22.224/27174.26.22.225 to 174.26.22.254174.26.22.25530
185174.26.23.0/27174.26.23.1 to 174.26.23.30174.26.23.3130
186174.26.23.32/27174.26.23.33 to 174.26.23.62174.26.23.6330
187174.26.23.64/27174.26.23.65 to 174.26.23.94174.26.23.9530
188174.26.23.96/27174.26.23.97 to 174.26.23.126174.26.23.12730
189174.26.23.128/27174.26.23.129 to 174.26.23.158174.26.23.15930
190174.26.23.160/27174.26.23.161 to 174.26.23.190174.26.23.19130
191174.26.23.192/27174.26.23.193 to 174.26.23.222174.26.23.22330
192174.26.23.224/27174.26.23.225 to 174.26.23.254174.26.23.25530
193174.26.24.0/27174.26.24.1 to 174.26.24.30174.26.24.3130
194174.26.24.32/27174.26.24.33 to 174.26.24.62174.26.24.6330
195174.26.24.64/27174.26.24.65 to 174.26.24.94174.26.24.9530
196174.26.24.96/27174.26.24.97 to 174.26.24.126174.26.24.12730
197174.26.24.128/27174.26.24.129 to 174.26.24.158174.26.24.15930
198174.26.24.160/27174.26.24.161 to 174.26.24.190174.26.24.19130
199174.26.24.192/27174.26.24.193 to 174.26.24.222174.26.24.22330
200174.26.24.224/27174.26.24.225 to 174.26.24.254174.26.24.25530
201174.26.25.0/27174.26.25.1 to 174.26.25.30174.26.25.3130
202174.26.25.32/27174.26.25.33 to 174.26.25.62174.26.25.6330
203174.26.25.64/27174.26.25.65 to 174.26.25.94174.26.25.9530
204174.26.25.96/27174.26.25.97 to 174.26.25.126174.26.25.12730
205174.26.25.128/27174.26.25.129 to 174.26.25.158174.26.25.15930
206174.26.25.160/27174.26.25.161 to 174.26.25.190174.26.25.19130
207174.26.25.192/27174.26.25.193 to 174.26.25.222174.26.25.22330
208174.26.25.224/27174.26.25.225 to 174.26.25.254174.26.25.25530
209174.26.26.0/27174.26.26.1 to 174.26.26.30174.26.26.3130
210174.26.26.32/27174.26.26.33 to 174.26.26.62174.26.26.6330
211174.26.26.64/27174.26.26.65 to 174.26.26.94174.26.26.9530
212174.26.26.96/27174.26.26.97 to 174.26.26.126174.26.26.12730
213174.26.26.128/27174.26.26.129 to 174.26.26.158174.26.26.15930
214174.26.26.160/27174.26.26.161 to 174.26.26.190174.26.26.19130
215174.26.26.192/27174.26.26.193 to 174.26.26.222174.26.26.22330
216174.26.26.224/27174.26.26.225 to 174.26.26.254174.26.26.25530
217174.26.27.0/27174.26.27.1 to 174.26.27.30174.26.27.3130
218174.26.27.32/27174.26.27.33 to 174.26.27.62174.26.27.6330
219174.26.27.64/27174.26.27.65 to 174.26.27.94174.26.27.9530
220174.26.27.96/27174.26.27.97 to 174.26.27.126174.26.27.12730
221174.26.27.128/27174.26.27.129 to 174.26.27.158174.26.27.15930
222174.26.27.160/27174.26.27.161 to 174.26.27.190174.26.27.19130
223174.26.27.192/27174.26.27.193 to 174.26.27.222174.26.27.22330
224174.26.27.224/27174.26.27.225 to 174.26.27.254174.26.27.25530
225174.26.28.0/27174.26.28.1 to 174.26.28.30174.26.28.3130
226174.26.28.32/27174.26.28.33 to 174.26.28.62174.26.28.6330
227174.26.28.64/27174.26.28.65 to 174.26.28.94174.26.28.9530
228174.26.28.96/27174.26.28.97 to 174.26.28.126174.26.28.12730
229174.26.28.128/27174.26.28.129 to 174.26.28.158174.26.28.15930
230174.26.28.160/27174.26.28.161 to 174.26.28.190174.26.28.19130
231174.26.28.192/27174.26.28.193 to 174.26.28.222174.26.28.22330
232174.26.28.224/27174.26.28.225 to 174.26.28.254174.26.28.25530
233174.26.29.0/27174.26.29.1 to 174.26.29.30174.26.29.3130
234174.26.29.32/27174.26.29.33 to 174.26.29.62174.26.29.6330
235174.26.29.64/27174.26.29.65 to 174.26.29.94174.26.29.9530
236174.26.29.96/27174.26.29.97 to 174.26.29.126174.26.29.12730
237174.26.29.128/27174.26.29.129 to 174.26.29.158174.26.29.15930
238174.26.29.160/27174.26.29.161 to 174.26.29.190174.26.29.19130
239174.26.29.192/27174.26.29.193 to 174.26.29.222174.26.29.22330
240174.26.29.224/27174.26.29.225 to 174.26.29.254174.26.29.25530
241174.26.30.0/27174.26.30.1 to 174.26.30.30174.26.30.3130
242174.26.30.32/27174.26.30.33 to 174.26.30.62174.26.30.6330
243174.26.30.64/27174.26.30.65 to 174.26.30.94174.26.30.9530
244174.26.30.96/27174.26.30.97 to 174.26.30.126174.26.30.12730
245174.26.30.128/27174.26.30.129 to 174.26.30.158174.26.30.15930
246174.26.30.160/27174.26.30.161 to 174.26.30.190174.26.30.19130
247174.26.30.192/27174.26.30.193 to 174.26.30.222174.26.30.22330
248174.26.30.224/27174.26.30.225 to 174.26.30.254174.26.30.25530
249174.26.31.0/27174.26.31.1 to 174.26.31.30174.26.31.3130
250174.26.31.32/27174.26.31.33 to 174.26.31.62174.26.31.6330
251174.26.31.64/27174.26.31.65 to 174.26.31.94174.26.31.9530
252174.26.31.96/27174.26.31.97 to 174.26.31.126174.26.31.12730
253174.26.31.128/27174.26.31.129 to 174.26.31.158174.26.31.15930
254174.26.31.160/27174.26.31.161 to 174.26.31.190174.26.31.19130
255174.26.31.192/27174.26.31.193 to 174.26.31.222174.26.31.22330
256174.26.31.224/27174.26.31.225 to 174.26.31.254174.26.31.25530

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.