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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.

Network114.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
114.0.0.0
Broadcast address
114.255.255.255
First usable
114.0.0.1
Last usable
114.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 72000000 · Integer 1912602624 to 1929379839
Reverse DNS zone
114.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110010..00000000.00000000.00000000114.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01110010..00000000.00000000.00000000114.0.0.0
Broadcast01110010..11111111.11111111.11111111114.255.255.255
Split into smaller subnets/19
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

114.0.0.0/8 makes 2,048 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1114.0.0.0/19114.0.0.1 to 114.0.31.254114.0.31.2558,190
2114.0.32.0/19114.0.32.1 to 114.0.63.254114.0.63.2558,190
3114.0.64.0/19114.0.64.1 to 114.0.95.254114.0.95.2558,190
4114.0.96.0/19114.0.96.1 to 114.0.127.254114.0.127.2558,190
5114.0.128.0/19114.0.128.1 to 114.0.159.254114.0.159.2558,190
6114.0.160.0/19114.0.160.1 to 114.0.191.254114.0.191.2558,190
7114.0.192.0/19114.0.192.1 to 114.0.223.254114.0.223.2558,190
8114.0.224.0/19114.0.224.1 to 114.0.255.254114.0.255.2558,190
9114.1.0.0/19114.1.0.1 to 114.1.31.254114.1.31.2558,190
10114.1.32.0/19114.1.32.1 to 114.1.63.254114.1.63.2558,190
11114.1.64.0/19114.1.64.1 to 114.1.95.254114.1.95.2558,190
12114.1.96.0/19114.1.96.1 to 114.1.127.254114.1.127.2558,190
13114.1.128.0/19114.1.128.1 to 114.1.159.254114.1.159.2558,190
14114.1.160.0/19114.1.160.1 to 114.1.191.254114.1.191.2558,190
15114.1.192.0/19114.1.192.1 to 114.1.223.254114.1.223.2558,190
16114.1.224.0/19114.1.224.1 to 114.1.255.254114.1.255.2558,190
17114.2.0.0/19114.2.0.1 to 114.2.31.254114.2.31.2558,190
18114.2.32.0/19114.2.32.1 to 114.2.63.254114.2.63.2558,190
19114.2.64.0/19114.2.64.1 to 114.2.95.254114.2.95.2558,190
20114.2.96.0/19114.2.96.1 to 114.2.127.254114.2.127.2558,190
21114.2.128.0/19114.2.128.1 to 114.2.159.254114.2.159.2558,190
22114.2.160.0/19114.2.160.1 to 114.2.191.254114.2.191.2558,190
23114.2.192.0/19114.2.192.1 to 114.2.223.254114.2.223.2558,190
24114.2.224.0/19114.2.224.1 to 114.2.255.254114.2.255.2558,190
25114.3.0.0/19114.3.0.1 to 114.3.31.254114.3.31.2558,190
26114.3.32.0/19114.3.32.1 to 114.3.63.254114.3.63.2558,190
27114.3.64.0/19114.3.64.1 to 114.3.95.254114.3.95.2558,190
28114.3.96.0/19114.3.96.1 to 114.3.127.254114.3.127.2558,190
29114.3.128.0/19114.3.128.1 to 114.3.159.254114.3.159.2558,190
30114.3.160.0/19114.3.160.1 to 114.3.191.254114.3.191.2558,190
31114.3.192.0/19114.3.192.1 to 114.3.223.254114.3.223.2558,190
32114.3.224.0/19114.3.224.1 to 114.3.255.254114.3.255.2558,190
33114.4.0.0/19114.4.0.1 to 114.4.31.254114.4.31.2558,190
34114.4.32.0/19114.4.32.1 to 114.4.63.254114.4.63.2558,190
35114.4.64.0/19114.4.64.1 to 114.4.95.254114.4.95.2558,190
36114.4.96.0/19114.4.96.1 to 114.4.127.254114.4.127.2558,190
37114.4.128.0/19114.4.128.1 to 114.4.159.254114.4.159.2558,190
38114.4.160.0/19114.4.160.1 to 114.4.191.254114.4.191.2558,190
39114.4.192.0/19114.4.192.1 to 114.4.223.254114.4.223.2558,190
40114.4.224.0/19114.4.224.1 to 114.4.255.254114.4.255.2558,190
41114.5.0.0/19114.5.0.1 to 114.5.31.254114.5.31.2558,190
42114.5.32.0/19114.5.32.1 to 114.5.63.254114.5.63.2558,190
43114.5.64.0/19114.5.64.1 to 114.5.95.254114.5.95.2558,190
44114.5.96.0/19114.5.96.1 to 114.5.127.254114.5.127.2558,190
45114.5.128.0/19114.5.128.1 to 114.5.159.254114.5.159.2558,190
46114.5.160.0/19114.5.160.1 to 114.5.191.254114.5.191.2558,190
47114.5.192.0/19114.5.192.1 to 114.5.223.254114.5.223.2558,190
48114.5.224.0/19114.5.224.1 to 114.5.255.254114.5.255.2558,190
49114.6.0.0/19114.6.0.1 to 114.6.31.254114.6.31.2558,190
50114.6.32.0/19114.6.32.1 to 114.6.63.254114.6.63.2558,190
51114.6.64.0/19114.6.64.1 to 114.6.95.254114.6.95.2558,190
52114.6.96.0/19114.6.96.1 to 114.6.127.254114.6.127.2558,190
53114.6.128.0/19114.6.128.1 to 114.6.159.254114.6.159.2558,190
54114.6.160.0/19114.6.160.1 to 114.6.191.254114.6.191.2558,190
55114.6.192.0/19114.6.192.1 to 114.6.223.254114.6.223.2558,190
56114.6.224.0/19114.6.224.1 to 114.6.255.254114.6.255.2558,190
57114.7.0.0/19114.7.0.1 to 114.7.31.254114.7.31.2558,190
58114.7.32.0/19114.7.32.1 to 114.7.63.254114.7.63.2558,190
59114.7.64.0/19114.7.64.1 to 114.7.95.254114.7.95.2558,190
60114.7.96.0/19114.7.96.1 to 114.7.127.254114.7.127.2558,190
61114.7.128.0/19114.7.128.1 to 114.7.159.254114.7.159.2558,190
62114.7.160.0/19114.7.160.1 to 114.7.191.254114.7.191.2558,190
63114.7.192.0/19114.7.192.1 to 114.7.223.254114.7.223.2558,190
64114.7.224.0/19114.7.224.1 to 114.7.255.254114.7.255.2558,190
65114.8.0.0/19114.8.0.1 to 114.8.31.254114.8.31.2558,190
66114.8.32.0/19114.8.32.1 to 114.8.63.254114.8.63.2558,190
67114.8.64.0/19114.8.64.1 to 114.8.95.254114.8.95.2558,190
68114.8.96.0/19114.8.96.1 to 114.8.127.254114.8.127.2558,190
69114.8.128.0/19114.8.128.1 to 114.8.159.254114.8.159.2558,190
70114.8.160.0/19114.8.160.1 to 114.8.191.254114.8.191.2558,190
71114.8.192.0/19114.8.192.1 to 114.8.223.254114.8.223.2558,190
72114.8.224.0/19114.8.224.1 to 114.8.255.254114.8.255.2558,190
73114.9.0.0/19114.9.0.1 to 114.9.31.254114.9.31.2558,190
74114.9.32.0/19114.9.32.1 to 114.9.63.254114.9.63.2558,190
75114.9.64.0/19114.9.64.1 to 114.9.95.254114.9.95.2558,190
76114.9.96.0/19114.9.96.1 to 114.9.127.254114.9.127.2558,190
77114.9.128.0/19114.9.128.1 to 114.9.159.254114.9.159.2558,190
78114.9.160.0/19114.9.160.1 to 114.9.191.254114.9.191.2558,190
79114.9.192.0/19114.9.192.1 to 114.9.223.254114.9.223.2558,190
80114.9.224.0/19114.9.224.1 to 114.9.255.254114.9.255.2558,190
81114.10.0.0/19114.10.0.1 to 114.10.31.254114.10.31.2558,190
82114.10.32.0/19114.10.32.1 to 114.10.63.254114.10.63.2558,190
83114.10.64.0/19114.10.64.1 to 114.10.95.254114.10.95.2558,190
84114.10.96.0/19114.10.96.1 to 114.10.127.254114.10.127.2558,190
85114.10.128.0/19114.10.128.1 to 114.10.159.254114.10.159.2558,190
86114.10.160.0/19114.10.160.1 to 114.10.191.254114.10.191.2558,190
87114.10.192.0/19114.10.192.1 to 114.10.223.254114.10.223.2558,190
88114.10.224.0/19114.10.224.1 to 114.10.255.254114.10.255.2558,190
89114.11.0.0/19114.11.0.1 to 114.11.31.254114.11.31.2558,190
90114.11.32.0/19114.11.32.1 to 114.11.63.254114.11.63.2558,190
91114.11.64.0/19114.11.64.1 to 114.11.95.254114.11.95.2558,190
92114.11.96.0/19114.11.96.1 to 114.11.127.254114.11.127.2558,190
93114.11.128.0/19114.11.128.1 to 114.11.159.254114.11.159.2558,190
94114.11.160.0/19114.11.160.1 to 114.11.191.254114.11.191.2558,190
95114.11.192.0/19114.11.192.1 to 114.11.223.254114.11.223.2558,190
96114.11.224.0/19114.11.224.1 to 114.11.255.254114.11.255.2558,190
97114.12.0.0/19114.12.0.1 to 114.12.31.254114.12.31.2558,190
98114.12.32.0/19114.12.32.1 to 114.12.63.254114.12.63.2558,190
99114.12.64.0/19114.12.64.1 to 114.12.95.254114.12.95.2558,190
100114.12.96.0/19114.12.96.1 to 114.12.127.254114.12.127.2558,190
101114.12.128.0/19114.12.128.1 to 114.12.159.254114.12.159.2558,190
102114.12.160.0/19114.12.160.1 to 114.12.191.254114.12.191.2558,190
103114.12.192.0/19114.12.192.1 to 114.12.223.254114.12.223.2558,190
104114.12.224.0/19114.12.224.1 to 114.12.255.254114.12.255.2558,190
105114.13.0.0/19114.13.0.1 to 114.13.31.254114.13.31.2558,190
106114.13.32.0/19114.13.32.1 to 114.13.63.254114.13.63.2558,190
107114.13.64.0/19114.13.64.1 to 114.13.95.254114.13.95.2558,190
108114.13.96.0/19114.13.96.1 to 114.13.127.254114.13.127.2558,190
109114.13.128.0/19114.13.128.1 to 114.13.159.254114.13.159.2558,190
110114.13.160.0/19114.13.160.1 to 114.13.191.254114.13.191.2558,190
111114.13.192.0/19114.13.192.1 to 114.13.223.254114.13.223.2558,190
112114.13.224.0/19114.13.224.1 to 114.13.255.254114.13.255.2558,190
113114.14.0.0/19114.14.0.1 to 114.14.31.254114.14.31.2558,190
114114.14.32.0/19114.14.32.1 to 114.14.63.254114.14.63.2558,190
115114.14.64.0/19114.14.64.1 to 114.14.95.254114.14.95.2558,190
116114.14.96.0/19114.14.96.1 to 114.14.127.254114.14.127.2558,190
117114.14.128.0/19114.14.128.1 to 114.14.159.254114.14.159.2558,190
118114.14.160.0/19114.14.160.1 to 114.14.191.254114.14.191.2558,190
119114.14.192.0/19114.14.192.1 to 114.14.223.254114.14.223.2558,190
120114.14.224.0/19114.14.224.1 to 114.14.255.254114.14.255.2558,190
121114.15.0.0/19114.15.0.1 to 114.15.31.254114.15.31.2558,190
122114.15.32.0/19114.15.32.1 to 114.15.63.254114.15.63.2558,190
123114.15.64.0/19114.15.64.1 to 114.15.95.254114.15.95.2558,190
124114.15.96.0/19114.15.96.1 to 114.15.127.254114.15.127.2558,190
125114.15.128.0/19114.15.128.1 to 114.15.159.254114.15.159.2558,190
126114.15.160.0/19114.15.160.1 to 114.15.191.254114.15.191.2558,190
127114.15.192.0/19114.15.192.1 to 114.15.223.254114.15.223.2558,190
128114.15.224.0/19114.15.224.1 to 114.15.255.254114.15.255.2558,190
129114.16.0.0/19114.16.0.1 to 114.16.31.254114.16.31.2558,190
130114.16.32.0/19114.16.32.1 to 114.16.63.254114.16.63.2558,190
131114.16.64.0/19114.16.64.1 to 114.16.95.254114.16.95.2558,190
132114.16.96.0/19114.16.96.1 to 114.16.127.254114.16.127.2558,190
133114.16.128.0/19114.16.128.1 to 114.16.159.254114.16.159.2558,190
134114.16.160.0/19114.16.160.1 to 114.16.191.254114.16.191.2558,190
135114.16.192.0/19114.16.192.1 to 114.16.223.254114.16.223.2558,190
136114.16.224.0/19114.16.224.1 to 114.16.255.254114.16.255.2558,190
137114.17.0.0/19114.17.0.1 to 114.17.31.254114.17.31.2558,190
138114.17.32.0/19114.17.32.1 to 114.17.63.254114.17.63.2558,190
139114.17.64.0/19114.17.64.1 to 114.17.95.254114.17.95.2558,190
140114.17.96.0/19114.17.96.1 to 114.17.127.254114.17.127.2558,190
141114.17.128.0/19114.17.128.1 to 114.17.159.254114.17.159.2558,190
142114.17.160.0/19114.17.160.1 to 114.17.191.254114.17.191.2558,190
143114.17.192.0/19114.17.192.1 to 114.17.223.254114.17.223.2558,190
144114.17.224.0/19114.17.224.1 to 114.17.255.254114.17.255.2558,190
145114.18.0.0/19114.18.0.1 to 114.18.31.254114.18.31.2558,190
146114.18.32.0/19114.18.32.1 to 114.18.63.254114.18.63.2558,190
147114.18.64.0/19114.18.64.1 to 114.18.95.254114.18.95.2558,190
148114.18.96.0/19114.18.96.1 to 114.18.127.254114.18.127.2558,190
149114.18.128.0/19114.18.128.1 to 114.18.159.254114.18.159.2558,190
150114.18.160.0/19114.18.160.1 to 114.18.191.254114.18.191.2558,190
151114.18.192.0/19114.18.192.1 to 114.18.223.254114.18.223.2558,190
152114.18.224.0/19114.18.224.1 to 114.18.255.254114.18.255.2558,190
153114.19.0.0/19114.19.0.1 to 114.19.31.254114.19.31.2558,190
154114.19.32.0/19114.19.32.1 to 114.19.63.254114.19.63.2558,190
155114.19.64.0/19114.19.64.1 to 114.19.95.254114.19.95.2558,190
156114.19.96.0/19114.19.96.1 to 114.19.127.254114.19.127.2558,190
157114.19.128.0/19114.19.128.1 to 114.19.159.254114.19.159.2558,190
158114.19.160.0/19114.19.160.1 to 114.19.191.254114.19.191.2558,190
159114.19.192.0/19114.19.192.1 to 114.19.223.254114.19.223.2558,190
160114.19.224.0/19114.19.224.1 to 114.19.255.254114.19.255.2558,190
161114.20.0.0/19114.20.0.1 to 114.20.31.254114.20.31.2558,190
162114.20.32.0/19114.20.32.1 to 114.20.63.254114.20.63.2558,190
163114.20.64.0/19114.20.64.1 to 114.20.95.254114.20.95.2558,190
164114.20.96.0/19114.20.96.1 to 114.20.127.254114.20.127.2558,190
165114.20.128.0/19114.20.128.1 to 114.20.159.254114.20.159.2558,190
166114.20.160.0/19114.20.160.1 to 114.20.191.254114.20.191.2558,190
167114.20.192.0/19114.20.192.1 to 114.20.223.254114.20.223.2558,190
168114.20.224.0/19114.20.224.1 to 114.20.255.254114.20.255.2558,190
169114.21.0.0/19114.21.0.1 to 114.21.31.254114.21.31.2558,190
170114.21.32.0/19114.21.32.1 to 114.21.63.254114.21.63.2558,190
171114.21.64.0/19114.21.64.1 to 114.21.95.254114.21.95.2558,190
172114.21.96.0/19114.21.96.1 to 114.21.127.254114.21.127.2558,190
173114.21.128.0/19114.21.128.1 to 114.21.159.254114.21.159.2558,190
174114.21.160.0/19114.21.160.1 to 114.21.191.254114.21.191.2558,190
175114.21.192.0/19114.21.192.1 to 114.21.223.254114.21.223.2558,190
176114.21.224.0/19114.21.224.1 to 114.21.255.254114.21.255.2558,190
177114.22.0.0/19114.22.0.1 to 114.22.31.254114.22.31.2558,190
178114.22.32.0/19114.22.32.1 to 114.22.63.254114.22.63.2558,190
179114.22.64.0/19114.22.64.1 to 114.22.95.254114.22.95.2558,190
180114.22.96.0/19114.22.96.1 to 114.22.127.254114.22.127.2558,190
181114.22.128.0/19114.22.128.1 to 114.22.159.254114.22.159.2558,190
182114.22.160.0/19114.22.160.1 to 114.22.191.254114.22.191.2558,190
183114.22.192.0/19114.22.192.1 to 114.22.223.254114.22.223.2558,190
184114.22.224.0/19114.22.224.1 to 114.22.255.254114.22.255.2558,190
185114.23.0.0/19114.23.0.1 to 114.23.31.254114.23.31.2558,190
186114.23.32.0/19114.23.32.1 to 114.23.63.254114.23.63.2558,190
187114.23.64.0/19114.23.64.1 to 114.23.95.254114.23.95.2558,190
188114.23.96.0/19114.23.96.1 to 114.23.127.254114.23.127.2558,190
189114.23.128.0/19114.23.128.1 to 114.23.159.254114.23.159.2558,190
190114.23.160.0/19114.23.160.1 to 114.23.191.254114.23.191.2558,190
191114.23.192.0/19114.23.192.1 to 114.23.223.254114.23.223.2558,190
192114.23.224.0/19114.23.224.1 to 114.23.255.254114.23.255.2558,190
193114.24.0.0/19114.24.0.1 to 114.24.31.254114.24.31.2558,190
194114.24.32.0/19114.24.32.1 to 114.24.63.254114.24.63.2558,190
195114.24.64.0/19114.24.64.1 to 114.24.95.254114.24.95.2558,190
196114.24.96.0/19114.24.96.1 to 114.24.127.254114.24.127.2558,190
197114.24.128.0/19114.24.128.1 to 114.24.159.254114.24.159.2558,190
198114.24.160.0/19114.24.160.1 to 114.24.191.254114.24.191.2558,190
199114.24.192.0/19114.24.192.1 to 114.24.223.254114.24.223.2558,190
200114.24.224.0/19114.24.224.1 to 114.24.255.254114.24.255.2558,190
201114.25.0.0/19114.25.0.1 to 114.25.31.254114.25.31.2558,190
202114.25.32.0/19114.25.32.1 to 114.25.63.254114.25.63.2558,190
203114.25.64.0/19114.25.64.1 to 114.25.95.254114.25.95.2558,190
204114.25.96.0/19114.25.96.1 to 114.25.127.254114.25.127.2558,190
205114.25.128.0/19114.25.128.1 to 114.25.159.254114.25.159.2558,190
206114.25.160.0/19114.25.160.1 to 114.25.191.254114.25.191.2558,190
207114.25.192.0/19114.25.192.1 to 114.25.223.254114.25.223.2558,190
208114.25.224.0/19114.25.224.1 to 114.25.255.254114.25.255.2558,190
209114.26.0.0/19114.26.0.1 to 114.26.31.254114.26.31.2558,190
210114.26.32.0/19114.26.32.1 to 114.26.63.254114.26.63.2558,190
211114.26.64.0/19114.26.64.1 to 114.26.95.254114.26.95.2558,190
212114.26.96.0/19114.26.96.1 to 114.26.127.254114.26.127.2558,190
213114.26.128.0/19114.26.128.1 to 114.26.159.254114.26.159.2558,190
214114.26.160.0/19114.26.160.1 to 114.26.191.254114.26.191.2558,190
215114.26.192.0/19114.26.192.1 to 114.26.223.254114.26.223.2558,190
216114.26.224.0/19114.26.224.1 to 114.26.255.254114.26.255.2558,190
217114.27.0.0/19114.27.0.1 to 114.27.31.254114.27.31.2558,190
218114.27.32.0/19114.27.32.1 to 114.27.63.254114.27.63.2558,190
219114.27.64.0/19114.27.64.1 to 114.27.95.254114.27.95.2558,190
220114.27.96.0/19114.27.96.1 to 114.27.127.254114.27.127.2558,190
221114.27.128.0/19114.27.128.1 to 114.27.159.254114.27.159.2558,190
222114.27.160.0/19114.27.160.1 to 114.27.191.254114.27.191.2558,190
223114.27.192.0/19114.27.192.1 to 114.27.223.254114.27.223.2558,190
224114.27.224.0/19114.27.224.1 to 114.27.255.254114.27.255.2558,190
225114.28.0.0/19114.28.0.1 to 114.28.31.254114.28.31.2558,190
226114.28.32.0/19114.28.32.1 to 114.28.63.254114.28.63.2558,190
227114.28.64.0/19114.28.64.1 to 114.28.95.254114.28.95.2558,190
228114.28.96.0/19114.28.96.1 to 114.28.127.254114.28.127.2558,190
229114.28.128.0/19114.28.128.1 to 114.28.159.254114.28.159.2558,190
230114.28.160.0/19114.28.160.1 to 114.28.191.254114.28.191.2558,190
231114.28.192.0/19114.28.192.1 to 114.28.223.254114.28.223.2558,190
232114.28.224.0/19114.28.224.1 to 114.28.255.254114.28.255.2558,190
233114.29.0.0/19114.29.0.1 to 114.29.31.254114.29.31.2558,190
234114.29.32.0/19114.29.32.1 to 114.29.63.254114.29.63.2558,190
235114.29.64.0/19114.29.64.1 to 114.29.95.254114.29.95.2558,190
236114.29.96.0/19114.29.96.1 to 114.29.127.254114.29.127.2558,190
237114.29.128.0/19114.29.128.1 to 114.29.159.254114.29.159.2558,190
238114.29.160.0/19114.29.160.1 to 114.29.191.254114.29.191.2558,190
239114.29.192.0/19114.29.192.1 to 114.29.223.254114.29.223.2558,190
240114.29.224.0/19114.29.224.1 to 114.29.255.254114.29.255.2558,190
241114.30.0.0/19114.30.0.1 to 114.30.31.254114.30.31.2558,190
242114.30.32.0/19114.30.32.1 to 114.30.63.254114.30.63.2558,190
243114.30.64.0/19114.30.64.1 to 114.30.95.254114.30.95.2558,190
244114.30.96.0/19114.30.96.1 to 114.30.127.254114.30.127.2558,190
245114.30.128.0/19114.30.128.1 to 114.30.159.254114.30.159.2558,190
246114.30.160.0/19114.30.160.1 to 114.30.191.254114.30.191.2558,190
247114.30.192.0/19114.30.192.1 to 114.30.223.254114.30.223.2558,190
248114.30.224.0/19114.30.224.1 to 114.30.255.254114.30.255.2558,190
249114.31.0.0/19114.31.0.1 to 114.31.31.254114.31.31.2558,190
250114.31.32.0/19114.31.32.1 to 114.31.63.254114.31.63.2558,190
251114.31.64.0/19114.31.64.1 to 114.31.95.254114.31.95.2558,190
252114.31.96.0/19114.31.96.1 to 114.31.127.254114.31.127.2558,190
253114.31.128.0/19114.31.128.1 to 114.31.159.254114.31.159.2558,190
254114.31.160.0/19114.31.160.1 to 114.31.191.254114.31.191.2558,190
255114.31.192.0/19114.31.192.1 to 114.31.223.254114.31.223.2558,190
256114.31.224.0/19114.31.224.1 to 114.31.255.254114.31.255.2558,190

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.