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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.

Network216.26.32.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
216.26.32.0
Broadcast address
216.26.63.255
First usable
216.26.32.1
Last usable
216.26.63.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Public public
Old class
C (default /24)
As numbers
Hex D81A2000 · Integer 3625590784 to 3625598975
Reverse DNS zones
32.26.216.in-addr.arpa
33.26.216.in-addr.arpa
34.26.216.in-addr.arpa
35.26.216.in-addr.arpa
36.26.216.in-addr.arpa
37.26.216.in-addr.arpa
38.26.216.in-addr.arpa
39.26.216.in-addr.arpa
40.26.216.in-addr.arpa
41.26.216.in-addr.arpa
42.26.216.in-addr.arpa
43.26.216.in-addr.arpa
44.26.216.in-addr.arpa
45.26.216.in-addr.arpa
46.26.216.in-addr.arpa
47.26.216.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11011000.00011010.00100000.00000000216.26.32.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network11011000.00011010.00100000.00000000216.26.32.0
Broadcast11011000.00011010.00111111.11111111216.26.63.255
Split into smaller subnets/28
/20 (2)/21 (4)/22 (8)/23 (16)/24 (32)/25 (64)/26 (128)/27 (256)/28 (512)/29 (1,024)/30 (2,048)/31 (4,096)

216.26.32.0/19 makes 512 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1216.26.32.0/28216.26.32.1 to 216.26.32.14216.26.32.1514
2216.26.32.16/28216.26.32.17 to 216.26.32.30216.26.32.3114
3216.26.32.32/28216.26.32.33 to 216.26.32.46216.26.32.4714
4216.26.32.48/28216.26.32.49 to 216.26.32.62216.26.32.6314
5216.26.32.64/28216.26.32.65 to 216.26.32.78216.26.32.7914
6216.26.32.80/28216.26.32.81 to 216.26.32.94216.26.32.9514
7216.26.32.96/28216.26.32.97 to 216.26.32.110216.26.32.11114
8216.26.32.112/28216.26.32.113 to 216.26.32.126216.26.32.12714
9216.26.32.128/28216.26.32.129 to 216.26.32.142216.26.32.14314
10216.26.32.144/28216.26.32.145 to 216.26.32.158216.26.32.15914
11216.26.32.160/28216.26.32.161 to 216.26.32.174216.26.32.17514
12216.26.32.176/28216.26.32.177 to 216.26.32.190216.26.32.19114
13216.26.32.192/28216.26.32.193 to 216.26.32.206216.26.32.20714
14216.26.32.208/28216.26.32.209 to 216.26.32.222216.26.32.22314
15216.26.32.224/28216.26.32.225 to 216.26.32.238216.26.32.23914
16216.26.32.240/28216.26.32.241 to 216.26.32.254216.26.32.25514
17216.26.33.0/28216.26.33.1 to 216.26.33.14216.26.33.1514
18216.26.33.16/28216.26.33.17 to 216.26.33.30216.26.33.3114
19216.26.33.32/28216.26.33.33 to 216.26.33.46216.26.33.4714
20216.26.33.48/28216.26.33.49 to 216.26.33.62216.26.33.6314
21216.26.33.64/28216.26.33.65 to 216.26.33.78216.26.33.7914
22216.26.33.80/28216.26.33.81 to 216.26.33.94216.26.33.9514
23216.26.33.96/28216.26.33.97 to 216.26.33.110216.26.33.11114
24216.26.33.112/28216.26.33.113 to 216.26.33.126216.26.33.12714
25216.26.33.128/28216.26.33.129 to 216.26.33.142216.26.33.14314
26216.26.33.144/28216.26.33.145 to 216.26.33.158216.26.33.15914
27216.26.33.160/28216.26.33.161 to 216.26.33.174216.26.33.17514
28216.26.33.176/28216.26.33.177 to 216.26.33.190216.26.33.19114
29216.26.33.192/28216.26.33.193 to 216.26.33.206216.26.33.20714
30216.26.33.208/28216.26.33.209 to 216.26.33.222216.26.33.22314
31216.26.33.224/28216.26.33.225 to 216.26.33.238216.26.33.23914
32216.26.33.240/28216.26.33.241 to 216.26.33.254216.26.33.25514
33216.26.34.0/28216.26.34.1 to 216.26.34.14216.26.34.1514
34216.26.34.16/28216.26.34.17 to 216.26.34.30216.26.34.3114
35216.26.34.32/28216.26.34.33 to 216.26.34.46216.26.34.4714
36216.26.34.48/28216.26.34.49 to 216.26.34.62216.26.34.6314
37216.26.34.64/28216.26.34.65 to 216.26.34.78216.26.34.7914
38216.26.34.80/28216.26.34.81 to 216.26.34.94216.26.34.9514
39216.26.34.96/28216.26.34.97 to 216.26.34.110216.26.34.11114
40216.26.34.112/28216.26.34.113 to 216.26.34.126216.26.34.12714
41216.26.34.128/28216.26.34.129 to 216.26.34.142216.26.34.14314
42216.26.34.144/28216.26.34.145 to 216.26.34.158216.26.34.15914
43216.26.34.160/28216.26.34.161 to 216.26.34.174216.26.34.17514
44216.26.34.176/28216.26.34.177 to 216.26.34.190216.26.34.19114
45216.26.34.192/28216.26.34.193 to 216.26.34.206216.26.34.20714
46216.26.34.208/28216.26.34.209 to 216.26.34.222216.26.34.22314
47216.26.34.224/28216.26.34.225 to 216.26.34.238216.26.34.23914
48216.26.34.240/28216.26.34.241 to 216.26.34.254216.26.34.25514
49216.26.35.0/28216.26.35.1 to 216.26.35.14216.26.35.1514
50216.26.35.16/28216.26.35.17 to 216.26.35.30216.26.35.3114
51216.26.35.32/28216.26.35.33 to 216.26.35.46216.26.35.4714
52216.26.35.48/28216.26.35.49 to 216.26.35.62216.26.35.6314
53216.26.35.64/28216.26.35.65 to 216.26.35.78216.26.35.7914
54216.26.35.80/28216.26.35.81 to 216.26.35.94216.26.35.9514
55216.26.35.96/28216.26.35.97 to 216.26.35.110216.26.35.11114
56216.26.35.112/28216.26.35.113 to 216.26.35.126216.26.35.12714
57216.26.35.128/28216.26.35.129 to 216.26.35.142216.26.35.14314
58216.26.35.144/28216.26.35.145 to 216.26.35.158216.26.35.15914
59216.26.35.160/28216.26.35.161 to 216.26.35.174216.26.35.17514
60216.26.35.176/28216.26.35.177 to 216.26.35.190216.26.35.19114
61216.26.35.192/28216.26.35.193 to 216.26.35.206216.26.35.20714
62216.26.35.208/28216.26.35.209 to 216.26.35.222216.26.35.22314
63216.26.35.224/28216.26.35.225 to 216.26.35.238216.26.35.23914
64216.26.35.240/28216.26.35.241 to 216.26.35.254216.26.35.25514
65216.26.36.0/28216.26.36.1 to 216.26.36.14216.26.36.1514
66216.26.36.16/28216.26.36.17 to 216.26.36.30216.26.36.3114
67216.26.36.32/28216.26.36.33 to 216.26.36.46216.26.36.4714
68216.26.36.48/28216.26.36.49 to 216.26.36.62216.26.36.6314
69216.26.36.64/28216.26.36.65 to 216.26.36.78216.26.36.7914
70216.26.36.80/28216.26.36.81 to 216.26.36.94216.26.36.9514
71216.26.36.96/28216.26.36.97 to 216.26.36.110216.26.36.11114
72216.26.36.112/28216.26.36.113 to 216.26.36.126216.26.36.12714
73216.26.36.128/28216.26.36.129 to 216.26.36.142216.26.36.14314
74216.26.36.144/28216.26.36.145 to 216.26.36.158216.26.36.15914
75216.26.36.160/28216.26.36.161 to 216.26.36.174216.26.36.17514
76216.26.36.176/28216.26.36.177 to 216.26.36.190216.26.36.19114
77216.26.36.192/28216.26.36.193 to 216.26.36.206216.26.36.20714
78216.26.36.208/28216.26.36.209 to 216.26.36.222216.26.36.22314
79216.26.36.224/28216.26.36.225 to 216.26.36.238216.26.36.23914
80216.26.36.240/28216.26.36.241 to 216.26.36.254216.26.36.25514
81216.26.37.0/28216.26.37.1 to 216.26.37.14216.26.37.1514
82216.26.37.16/28216.26.37.17 to 216.26.37.30216.26.37.3114
83216.26.37.32/28216.26.37.33 to 216.26.37.46216.26.37.4714
84216.26.37.48/28216.26.37.49 to 216.26.37.62216.26.37.6314
85216.26.37.64/28216.26.37.65 to 216.26.37.78216.26.37.7914
86216.26.37.80/28216.26.37.81 to 216.26.37.94216.26.37.9514
87216.26.37.96/28216.26.37.97 to 216.26.37.110216.26.37.11114
88216.26.37.112/28216.26.37.113 to 216.26.37.126216.26.37.12714
89216.26.37.128/28216.26.37.129 to 216.26.37.142216.26.37.14314
90216.26.37.144/28216.26.37.145 to 216.26.37.158216.26.37.15914
91216.26.37.160/28216.26.37.161 to 216.26.37.174216.26.37.17514
92216.26.37.176/28216.26.37.177 to 216.26.37.190216.26.37.19114
93216.26.37.192/28216.26.37.193 to 216.26.37.206216.26.37.20714
94216.26.37.208/28216.26.37.209 to 216.26.37.222216.26.37.22314
95216.26.37.224/28216.26.37.225 to 216.26.37.238216.26.37.23914
96216.26.37.240/28216.26.37.241 to 216.26.37.254216.26.37.25514
97216.26.38.0/28216.26.38.1 to 216.26.38.14216.26.38.1514
98216.26.38.16/28216.26.38.17 to 216.26.38.30216.26.38.3114
99216.26.38.32/28216.26.38.33 to 216.26.38.46216.26.38.4714
100216.26.38.48/28216.26.38.49 to 216.26.38.62216.26.38.6314
101216.26.38.64/28216.26.38.65 to 216.26.38.78216.26.38.7914
102216.26.38.80/28216.26.38.81 to 216.26.38.94216.26.38.9514
103216.26.38.96/28216.26.38.97 to 216.26.38.110216.26.38.11114
104216.26.38.112/28216.26.38.113 to 216.26.38.126216.26.38.12714
105216.26.38.128/28216.26.38.129 to 216.26.38.142216.26.38.14314
106216.26.38.144/28216.26.38.145 to 216.26.38.158216.26.38.15914
107216.26.38.160/28216.26.38.161 to 216.26.38.174216.26.38.17514
108216.26.38.176/28216.26.38.177 to 216.26.38.190216.26.38.19114
109216.26.38.192/28216.26.38.193 to 216.26.38.206216.26.38.20714
110216.26.38.208/28216.26.38.209 to 216.26.38.222216.26.38.22314
111216.26.38.224/28216.26.38.225 to 216.26.38.238216.26.38.23914
112216.26.38.240/28216.26.38.241 to 216.26.38.254216.26.38.25514
113216.26.39.0/28216.26.39.1 to 216.26.39.14216.26.39.1514
114216.26.39.16/28216.26.39.17 to 216.26.39.30216.26.39.3114
115216.26.39.32/28216.26.39.33 to 216.26.39.46216.26.39.4714
116216.26.39.48/28216.26.39.49 to 216.26.39.62216.26.39.6314
117216.26.39.64/28216.26.39.65 to 216.26.39.78216.26.39.7914
118216.26.39.80/28216.26.39.81 to 216.26.39.94216.26.39.9514
119216.26.39.96/28216.26.39.97 to 216.26.39.110216.26.39.11114
120216.26.39.112/28216.26.39.113 to 216.26.39.126216.26.39.12714
121216.26.39.128/28216.26.39.129 to 216.26.39.142216.26.39.14314
122216.26.39.144/28216.26.39.145 to 216.26.39.158216.26.39.15914
123216.26.39.160/28216.26.39.161 to 216.26.39.174216.26.39.17514
124216.26.39.176/28216.26.39.177 to 216.26.39.190216.26.39.19114
125216.26.39.192/28216.26.39.193 to 216.26.39.206216.26.39.20714
126216.26.39.208/28216.26.39.209 to 216.26.39.222216.26.39.22314
127216.26.39.224/28216.26.39.225 to 216.26.39.238216.26.39.23914
128216.26.39.240/28216.26.39.241 to 216.26.39.254216.26.39.25514
129216.26.40.0/28216.26.40.1 to 216.26.40.14216.26.40.1514
130216.26.40.16/28216.26.40.17 to 216.26.40.30216.26.40.3114
131216.26.40.32/28216.26.40.33 to 216.26.40.46216.26.40.4714
132216.26.40.48/28216.26.40.49 to 216.26.40.62216.26.40.6314
133216.26.40.64/28216.26.40.65 to 216.26.40.78216.26.40.7914
134216.26.40.80/28216.26.40.81 to 216.26.40.94216.26.40.9514
135216.26.40.96/28216.26.40.97 to 216.26.40.110216.26.40.11114
136216.26.40.112/28216.26.40.113 to 216.26.40.126216.26.40.12714
137216.26.40.128/28216.26.40.129 to 216.26.40.142216.26.40.14314
138216.26.40.144/28216.26.40.145 to 216.26.40.158216.26.40.15914
139216.26.40.160/28216.26.40.161 to 216.26.40.174216.26.40.17514
140216.26.40.176/28216.26.40.177 to 216.26.40.190216.26.40.19114
141216.26.40.192/28216.26.40.193 to 216.26.40.206216.26.40.20714
142216.26.40.208/28216.26.40.209 to 216.26.40.222216.26.40.22314
143216.26.40.224/28216.26.40.225 to 216.26.40.238216.26.40.23914
144216.26.40.240/28216.26.40.241 to 216.26.40.254216.26.40.25514
145216.26.41.0/28216.26.41.1 to 216.26.41.14216.26.41.1514
146216.26.41.16/28216.26.41.17 to 216.26.41.30216.26.41.3114
147216.26.41.32/28216.26.41.33 to 216.26.41.46216.26.41.4714
148216.26.41.48/28216.26.41.49 to 216.26.41.62216.26.41.6314
149216.26.41.64/28216.26.41.65 to 216.26.41.78216.26.41.7914
150216.26.41.80/28216.26.41.81 to 216.26.41.94216.26.41.9514
151216.26.41.96/28216.26.41.97 to 216.26.41.110216.26.41.11114
152216.26.41.112/28216.26.41.113 to 216.26.41.126216.26.41.12714
153216.26.41.128/28216.26.41.129 to 216.26.41.142216.26.41.14314
154216.26.41.144/28216.26.41.145 to 216.26.41.158216.26.41.15914
155216.26.41.160/28216.26.41.161 to 216.26.41.174216.26.41.17514
156216.26.41.176/28216.26.41.177 to 216.26.41.190216.26.41.19114
157216.26.41.192/28216.26.41.193 to 216.26.41.206216.26.41.20714
158216.26.41.208/28216.26.41.209 to 216.26.41.222216.26.41.22314
159216.26.41.224/28216.26.41.225 to 216.26.41.238216.26.41.23914
160216.26.41.240/28216.26.41.241 to 216.26.41.254216.26.41.25514
161216.26.42.0/28216.26.42.1 to 216.26.42.14216.26.42.1514
162216.26.42.16/28216.26.42.17 to 216.26.42.30216.26.42.3114
163216.26.42.32/28216.26.42.33 to 216.26.42.46216.26.42.4714
164216.26.42.48/28216.26.42.49 to 216.26.42.62216.26.42.6314
165216.26.42.64/28216.26.42.65 to 216.26.42.78216.26.42.7914
166216.26.42.80/28216.26.42.81 to 216.26.42.94216.26.42.9514
167216.26.42.96/28216.26.42.97 to 216.26.42.110216.26.42.11114
168216.26.42.112/28216.26.42.113 to 216.26.42.126216.26.42.12714
169216.26.42.128/28216.26.42.129 to 216.26.42.142216.26.42.14314
170216.26.42.144/28216.26.42.145 to 216.26.42.158216.26.42.15914
171216.26.42.160/28216.26.42.161 to 216.26.42.174216.26.42.17514
172216.26.42.176/28216.26.42.177 to 216.26.42.190216.26.42.19114
173216.26.42.192/28216.26.42.193 to 216.26.42.206216.26.42.20714
174216.26.42.208/28216.26.42.209 to 216.26.42.222216.26.42.22314
175216.26.42.224/28216.26.42.225 to 216.26.42.238216.26.42.23914
176216.26.42.240/28216.26.42.241 to 216.26.42.254216.26.42.25514
177216.26.43.0/28216.26.43.1 to 216.26.43.14216.26.43.1514
178216.26.43.16/28216.26.43.17 to 216.26.43.30216.26.43.3114
179216.26.43.32/28216.26.43.33 to 216.26.43.46216.26.43.4714
180216.26.43.48/28216.26.43.49 to 216.26.43.62216.26.43.6314
181216.26.43.64/28216.26.43.65 to 216.26.43.78216.26.43.7914
182216.26.43.80/28216.26.43.81 to 216.26.43.94216.26.43.9514
183216.26.43.96/28216.26.43.97 to 216.26.43.110216.26.43.11114
184216.26.43.112/28216.26.43.113 to 216.26.43.126216.26.43.12714
185216.26.43.128/28216.26.43.129 to 216.26.43.142216.26.43.14314
186216.26.43.144/28216.26.43.145 to 216.26.43.158216.26.43.15914
187216.26.43.160/28216.26.43.161 to 216.26.43.174216.26.43.17514
188216.26.43.176/28216.26.43.177 to 216.26.43.190216.26.43.19114
189216.26.43.192/28216.26.43.193 to 216.26.43.206216.26.43.20714
190216.26.43.208/28216.26.43.209 to 216.26.43.222216.26.43.22314
191216.26.43.224/28216.26.43.225 to 216.26.43.238216.26.43.23914
192216.26.43.240/28216.26.43.241 to 216.26.43.254216.26.43.25514
193216.26.44.0/28216.26.44.1 to 216.26.44.14216.26.44.1514
194216.26.44.16/28216.26.44.17 to 216.26.44.30216.26.44.3114
195216.26.44.32/28216.26.44.33 to 216.26.44.46216.26.44.4714
196216.26.44.48/28216.26.44.49 to 216.26.44.62216.26.44.6314
197216.26.44.64/28216.26.44.65 to 216.26.44.78216.26.44.7914
198216.26.44.80/28216.26.44.81 to 216.26.44.94216.26.44.9514
199216.26.44.96/28216.26.44.97 to 216.26.44.110216.26.44.11114
200216.26.44.112/28216.26.44.113 to 216.26.44.126216.26.44.12714
201216.26.44.128/28216.26.44.129 to 216.26.44.142216.26.44.14314
202216.26.44.144/28216.26.44.145 to 216.26.44.158216.26.44.15914
203216.26.44.160/28216.26.44.161 to 216.26.44.174216.26.44.17514
204216.26.44.176/28216.26.44.177 to 216.26.44.190216.26.44.19114
205216.26.44.192/28216.26.44.193 to 216.26.44.206216.26.44.20714
206216.26.44.208/28216.26.44.209 to 216.26.44.222216.26.44.22314
207216.26.44.224/28216.26.44.225 to 216.26.44.238216.26.44.23914
208216.26.44.240/28216.26.44.241 to 216.26.44.254216.26.44.25514
209216.26.45.0/28216.26.45.1 to 216.26.45.14216.26.45.1514
210216.26.45.16/28216.26.45.17 to 216.26.45.30216.26.45.3114
211216.26.45.32/28216.26.45.33 to 216.26.45.46216.26.45.4714
212216.26.45.48/28216.26.45.49 to 216.26.45.62216.26.45.6314
213216.26.45.64/28216.26.45.65 to 216.26.45.78216.26.45.7914
214216.26.45.80/28216.26.45.81 to 216.26.45.94216.26.45.9514
215216.26.45.96/28216.26.45.97 to 216.26.45.110216.26.45.11114
216216.26.45.112/28216.26.45.113 to 216.26.45.126216.26.45.12714
217216.26.45.128/28216.26.45.129 to 216.26.45.142216.26.45.14314
218216.26.45.144/28216.26.45.145 to 216.26.45.158216.26.45.15914
219216.26.45.160/28216.26.45.161 to 216.26.45.174216.26.45.17514
220216.26.45.176/28216.26.45.177 to 216.26.45.190216.26.45.19114
221216.26.45.192/28216.26.45.193 to 216.26.45.206216.26.45.20714
222216.26.45.208/28216.26.45.209 to 216.26.45.222216.26.45.22314
223216.26.45.224/28216.26.45.225 to 216.26.45.238216.26.45.23914
224216.26.45.240/28216.26.45.241 to 216.26.45.254216.26.45.25514
225216.26.46.0/28216.26.46.1 to 216.26.46.14216.26.46.1514
226216.26.46.16/28216.26.46.17 to 216.26.46.30216.26.46.3114
227216.26.46.32/28216.26.46.33 to 216.26.46.46216.26.46.4714
228216.26.46.48/28216.26.46.49 to 216.26.46.62216.26.46.6314
229216.26.46.64/28216.26.46.65 to 216.26.46.78216.26.46.7914
230216.26.46.80/28216.26.46.81 to 216.26.46.94216.26.46.9514
231216.26.46.96/28216.26.46.97 to 216.26.46.110216.26.46.11114
232216.26.46.112/28216.26.46.113 to 216.26.46.126216.26.46.12714
233216.26.46.128/28216.26.46.129 to 216.26.46.142216.26.46.14314
234216.26.46.144/28216.26.46.145 to 216.26.46.158216.26.46.15914
235216.26.46.160/28216.26.46.161 to 216.26.46.174216.26.46.17514
236216.26.46.176/28216.26.46.177 to 216.26.46.190216.26.46.19114
237216.26.46.192/28216.26.46.193 to 216.26.46.206216.26.46.20714
238216.26.46.208/28216.26.46.209 to 216.26.46.222216.26.46.22314
239216.26.46.224/28216.26.46.225 to 216.26.46.238216.26.46.23914
240216.26.46.240/28216.26.46.241 to 216.26.46.254216.26.46.25514
241216.26.47.0/28216.26.47.1 to 216.26.47.14216.26.47.1514
242216.26.47.16/28216.26.47.17 to 216.26.47.30216.26.47.3114
243216.26.47.32/28216.26.47.33 to 216.26.47.46216.26.47.4714
244216.26.47.48/28216.26.47.49 to 216.26.47.62216.26.47.6314
245216.26.47.64/28216.26.47.65 to 216.26.47.78216.26.47.7914
246216.26.47.80/28216.26.47.81 to 216.26.47.94216.26.47.9514
247216.26.47.96/28216.26.47.97 to 216.26.47.110216.26.47.11114
248216.26.47.112/28216.26.47.113 to 216.26.47.126216.26.47.12714
249216.26.47.128/28216.26.47.129 to 216.26.47.142216.26.47.14314
250216.26.47.144/28216.26.47.145 to 216.26.47.158216.26.47.15914
251216.26.47.160/28216.26.47.161 to 216.26.47.174216.26.47.17514
252216.26.47.176/28216.26.47.177 to 216.26.47.190216.26.47.19114
253216.26.47.192/28216.26.47.193 to 216.26.47.206216.26.47.20714
254216.26.47.208/28216.26.47.209 to 216.26.47.222216.26.47.22314
255216.26.47.224/28216.26.47.225 to 216.26.47.238216.26.47.23914
256216.26.47.240/28216.26.47.241 to 216.26.47.254216.26.47.25514

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

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.