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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/18
/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 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1114.0.0.0/18114.0.0.1 to 114.0.63.254114.0.63.25516,382
2114.0.64.0/18114.0.64.1 to 114.0.127.254114.0.127.25516,382
3114.0.128.0/18114.0.128.1 to 114.0.191.254114.0.191.25516,382
4114.0.192.0/18114.0.192.1 to 114.0.255.254114.0.255.25516,382
5114.1.0.0/18114.1.0.1 to 114.1.63.254114.1.63.25516,382
6114.1.64.0/18114.1.64.1 to 114.1.127.254114.1.127.25516,382
7114.1.128.0/18114.1.128.1 to 114.1.191.254114.1.191.25516,382
8114.1.192.0/18114.1.192.1 to 114.1.255.254114.1.255.25516,382
9114.2.0.0/18114.2.0.1 to 114.2.63.254114.2.63.25516,382
10114.2.64.0/18114.2.64.1 to 114.2.127.254114.2.127.25516,382
11114.2.128.0/18114.2.128.1 to 114.2.191.254114.2.191.25516,382
12114.2.192.0/18114.2.192.1 to 114.2.255.254114.2.255.25516,382
13114.3.0.0/18114.3.0.1 to 114.3.63.254114.3.63.25516,382
14114.3.64.0/18114.3.64.1 to 114.3.127.254114.3.127.25516,382
15114.3.128.0/18114.3.128.1 to 114.3.191.254114.3.191.25516,382
16114.3.192.0/18114.3.192.1 to 114.3.255.254114.3.255.25516,382
17114.4.0.0/18114.4.0.1 to 114.4.63.254114.4.63.25516,382
18114.4.64.0/18114.4.64.1 to 114.4.127.254114.4.127.25516,382
19114.4.128.0/18114.4.128.1 to 114.4.191.254114.4.191.25516,382
20114.4.192.0/18114.4.192.1 to 114.4.255.254114.4.255.25516,382
21114.5.0.0/18114.5.0.1 to 114.5.63.254114.5.63.25516,382
22114.5.64.0/18114.5.64.1 to 114.5.127.254114.5.127.25516,382
23114.5.128.0/18114.5.128.1 to 114.5.191.254114.5.191.25516,382
24114.5.192.0/18114.5.192.1 to 114.5.255.254114.5.255.25516,382
25114.6.0.0/18114.6.0.1 to 114.6.63.254114.6.63.25516,382
26114.6.64.0/18114.6.64.1 to 114.6.127.254114.6.127.25516,382
27114.6.128.0/18114.6.128.1 to 114.6.191.254114.6.191.25516,382
28114.6.192.0/18114.6.192.1 to 114.6.255.254114.6.255.25516,382
29114.7.0.0/18114.7.0.1 to 114.7.63.254114.7.63.25516,382
30114.7.64.0/18114.7.64.1 to 114.7.127.254114.7.127.25516,382
31114.7.128.0/18114.7.128.1 to 114.7.191.254114.7.191.25516,382
32114.7.192.0/18114.7.192.1 to 114.7.255.254114.7.255.25516,382
33114.8.0.0/18114.8.0.1 to 114.8.63.254114.8.63.25516,382
34114.8.64.0/18114.8.64.1 to 114.8.127.254114.8.127.25516,382
35114.8.128.0/18114.8.128.1 to 114.8.191.254114.8.191.25516,382
36114.8.192.0/18114.8.192.1 to 114.8.255.254114.8.255.25516,382
37114.9.0.0/18114.9.0.1 to 114.9.63.254114.9.63.25516,382
38114.9.64.0/18114.9.64.1 to 114.9.127.254114.9.127.25516,382
39114.9.128.0/18114.9.128.1 to 114.9.191.254114.9.191.25516,382
40114.9.192.0/18114.9.192.1 to 114.9.255.254114.9.255.25516,382
41114.10.0.0/18114.10.0.1 to 114.10.63.254114.10.63.25516,382
42114.10.64.0/18114.10.64.1 to 114.10.127.254114.10.127.25516,382
43114.10.128.0/18114.10.128.1 to 114.10.191.254114.10.191.25516,382
44114.10.192.0/18114.10.192.1 to 114.10.255.254114.10.255.25516,382
45114.11.0.0/18114.11.0.1 to 114.11.63.254114.11.63.25516,382
46114.11.64.0/18114.11.64.1 to 114.11.127.254114.11.127.25516,382
47114.11.128.0/18114.11.128.1 to 114.11.191.254114.11.191.25516,382
48114.11.192.0/18114.11.192.1 to 114.11.255.254114.11.255.25516,382
49114.12.0.0/18114.12.0.1 to 114.12.63.254114.12.63.25516,382
50114.12.64.0/18114.12.64.1 to 114.12.127.254114.12.127.25516,382
51114.12.128.0/18114.12.128.1 to 114.12.191.254114.12.191.25516,382
52114.12.192.0/18114.12.192.1 to 114.12.255.254114.12.255.25516,382
53114.13.0.0/18114.13.0.1 to 114.13.63.254114.13.63.25516,382
54114.13.64.0/18114.13.64.1 to 114.13.127.254114.13.127.25516,382
55114.13.128.0/18114.13.128.1 to 114.13.191.254114.13.191.25516,382
56114.13.192.0/18114.13.192.1 to 114.13.255.254114.13.255.25516,382
57114.14.0.0/18114.14.0.1 to 114.14.63.254114.14.63.25516,382
58114.14.64.0/18114.14.64.1 to 114.14.127.254114.14.127.25516,382
59114.14.128.0/18114.14.128.1 to 114.14.191.254114.14.191.25516,382
60114.14.192.0/18114.14.192.1 to 114.14.255.254114.14.255.25516,382
61114.15.0.0/18114.15.0.1 to 114.15.63.254114.15.63.25516,382
62114.15.64.0/18114.15.64.1 to 114.15.127.254114.15.127.25516,382
63114.15.128.0/18114.15.128.1 to 114.15.191.254114.15.191.25516,382
64114.15.192.0/18114.15.192.1 to 114.15.255.254114.15.255.25516,382
65114.16.0.0/18114.16.0.1 to 114.16.63.254114.16.63.25516,382
66114.16.64.0/18114.16.64.1 to 114.16.127.254114.16.127.25516,382
67114.16.128.0/18114.16.128.1 to 114.16.191.254114.16.191.25516,382
68114.16.192.0/18114.16.192.1 to 114.16.255.254114.16.255.25516,382
69114.17.0.0/18114.17.0.1 to 114.17.63.254114.17.63.25516,382
70114.17.64.0/18114.17.64.1 to 114.17.127.254114.17.127.25516,382
71114.17.128.0/18114.17.128.1 to 114.17.191.254114.17.191.25516,382
72114.17.192.0/18114.17.192.1 to 114.17.255.254114.17.255.25516,382
73114.18.0.0/18114.18.0.1 to 114.18.63.254114.18.63.25516,382
74114.18.64.0/18114.18.64.1 to 114.18.127.254114.18.127.25516,382
75114.18.128.0/18114.18.128.1 to 114.18.191.254114.18.191.25516,382
76114.18.192.0/18114.18.192.1 to 114.18.255.254114.18.255.25516,382
77114.19.0.0/18114.19.0.1 to 114.19.63.254114.19.63.25516,382
78114.19.64.0/18114.19.64.1 to 114.19.127.254114.19.127.25516,382
79114.19.128.0/18114.19.128.1 to 114.19.191.254114.19.191.25516,382
80114.19.192.0/18114.19.192.1 to 114.19.255.254114.19.255.25516,382
81114.20.0.0/18114.20.0.1 to 114.20.63.254114.20.63.25516,382
82114.20.64.0/18114.20.64.1 to 114.20.127.254114.20.127.25516,382
83114.20.128.0/18114.20.128.1 to 114.20.191.254114.20.191.25516,382
84114.20.192.0/18114.20.192.1 to 114.20.255.254114.20.255.25516,382
85114.21.0.0/18114.21.0.1 to 114.21.63.254114.21.63.25516,382
86114.21.64.0/18114.21.64.1 to 114.21.127.254114.21.127.25516,382
87114.21.128.0/18114.21.128.1 to 114.21.191.254114.21.191.25516,382
88114.21.192.0/18114.21.192.1 to 114.21.255.254114.21.255.25516,382
89114.22.0.0/18114.22.0.1 to 114.22.63.254114.22.63.25516,382
90114.22.64.0/18114.22.64.1 to 114.22.127.254114.22.127.25516,382
91114.22.128.0/18114.22.128.1 to 114.22.191.254114.22.191.25516,382
92114.22.192.0/18114.22.192.1 to 114.22.255.254114.22.255.25516,382
93114.23.0.0/18114.23.0.1 to 114.23.63.254114.23.63.25516,382
94114.23.64.0/18114.23.64.1 to 114.23.127.254114.23.127.25516,382
95114.23.128.0/18114.23.128.1 to 114.23.191.254114.23.191.25516,382
96114.23.192.0/18114.23.192.1 to 114.23.255.254114.23.255.25516,382
97114.24.0.0/18114.24.0.1 to 114.24.63.254114.24.63.25516,382
98114.24.64.0/18114.24.64.1 to 114.24.127.254114.24.127.25516,382
99114.24.128.0/18114.24.128.1 to 114.24.191.254114.24.191.25516,382
100114.24.192.0/18114.24.192.1 to 114.24.255.254114.24.255.25516,382
101114.25.0.0/18114.25.0.1 to 114.25.63.254114.25.63.25516,382
102114.25.64.0/18114.25.64.1 to 114.25.127.254114.25.127.25516,382
103114.25.128.0/18114.25.128.1 to 114.25.191.254114.25.191.25516,382
104114.25.192.0/18114.25.192.1 to 114.25.255.254114.25.255.25516,382
105114.26.0.0/18114.26.0.1 to 114.26.63.254114.26.63.25516,382
106114.26.64.0/18114.26.64.1 to 114.26.127.254114.26.127.25516,382
107114.26.128.0/18114.26.128.1 to 114.26.191.254114.26.191.25516,382
108114.26.192.0/18114.26.192.1 to 114.26.255.254114.26.255.25516,382
109114.27.0.0/18114.27.0.1 to 114.27.63.254114.27.63.25516,382
110114.27.64.0/18114.27.64.1 to 114.27.127.254114.27.127.25516,382
111114.27.128.0/18114.27.128.1 to 114.27.191.254114.27.191.25516,382
112114.27.192.0/18114.27.192.1 to 114.27.255.254114.27.255.25516,382
113114.28.0.0/18114.28.0.1 to 114.28.63.254114.28.63.25516,382
114114.28.64.0/18114.28.64.1 to 114.28.127.254114.28.127.25516,382
115114.28.128.0/18114.28.128.1 to 114.28.191.254114.28.191.25516,382
116114.28.192.0/18114.28.192.1 to 114.28.255.254114.28.255.25516,382
117114.29.0.0/18114.29.0.1 to 114.29.63.254114.29.63.25516,382
118114.29.64.0/18114.29.64.1 to 114.29.127.254114.29.127.25516,382
119114.29.128.0/18114.29.128.1 to 114.29.191.254114.29.191.25516,382
120114.29.192.0/18114.29.192.1 to 114.29.255.254114.29.255.25516,382
121114.30.0.0/18114.30.0.1 to 114.30.63.254114.30.63.25516,382
122114.30.64.0/18114.30.64.1 to 114.30.127.254114.30.127.25516,382
123114.30.128.0/18114.30.128.1 to 114.30.191.254114.30.191.25516,382
124114.30.192.0/18114.30.192.1 to 114.30.255.254114.30.255.25516,382
125114.31.0.0/18114.31.0.1 to 114.31.63.254114.31.63.25516,382
126114.31.64.0/18114.31.64.1 to 114.31.127.254114.31.127.25516,382
127114.31.128.0/18114.31.128.1 to 114.31.191.254114.31.191.25516,382
128114.31.192.0/18114.31.192.1 to 114.31.255.254114.31.255.25516,382
129114.32.0.0/18114.32.0.1 to 114.32.63.254114.32.63.25516,382
130114.32.64.0/18114.32.64.1 to 114.32.127.254114.32.127.25516,382
131114.32.128.0/18114.32.128.1 to 114.32.191.254114.32.191.25516,382
132114.32.192.0/18114.32.192.1 to 114.32.255.254114.32.255.25516,382
133114.33.0.0/18114.33.0.1 to 114.33.63.254114.33.63.25516,382
134114.33.64.0/18114.33.64.1 to 114.33.127.254114.33.127.25516,382
135114.33.128.0/18114.33.128.1 to 114.33.191.254114.33.191.25516,382
136114.33.192.0/18114.33.192.1 to 114.33.255.254114.33.255.25516,382
137114.34.0.0/18114.34.0.1 to 114.34.63.254114.34.63.25516,382
138114.34.64.0/18114.34.64.1 to 114.34.127.254114.34.127.25516,382
139114.34.128.0/18114.34.128.1 to 114.34.191.254114.34.191.25516,382
140114.34.192.0/18114.34.192.1 to 114.34.255.254114.34.255.25516,382
141114.35.0.0/18114.35.0.1 to 114.35.63.254114.35.63.25516,382
142114.35.64.0/18114.35.64.1 to 114.35.127.254114.35.127.25516,382
143114.35.128.0/18114.35.128.1 to 114.35.191.254114.35.191.25516,382
144114.35.192.0/18114.35.192.1 to 114.35.255.254114.35.255.25516,382
145114.36.0.0/18114.36.0.1 to 114.36.63.254114.36.63.25516,382
146114.36.64.0/18114.36.64.1 to 114.36.127.254114.36.127.25516,382
147114.36.128.0/18114.36.128.1 to 114.36.191.254114.36.191.25516,382
148114.36.192.0/18114.36.192.1 to 114.36.255.254114.36.255.25516,382
149114.37.0.0/18114.37.0.1 to 114.37.63.254114.37.63.25516,382
150114.37.64.0/18114.37.64.1 to 114.37.127.254114.37.127.25516,382
151114.37.128.0/18114.37.128.1 to 114.37.191.254114.37.191.25516,382
152114.37.192.0/18114.37.192.1 to 114.37.255.254114.37.255.25516,382
153114.38.0.0/18114.38.0.1 to 114.38.63.254114.38.63.25516,382
154114.38.64.0/18114.38.64.1 to 114.38.127.254114.38.127.25516,382
155114.38.128.0/18114.38.128.1 to 114.38.191.254114.38.191.25516,382
156114.38.192.0/18114.38.192.1 to 114.38.255.254114.38.255.25516,382
157114.39.0.0/18114.39.0.1 to 114.39.63.254114.39.63.25516,382
158114.39.64.0/18114.39.64.1 to 114.39.127.254114.39.127.25516,382
159114.39.128.0/18114.39.128.1 to 114.39.191.254114.39.191.25516,382
160114.39.192.0/18114.39.192.1 to 114.39.255.254114.39.255.25516,382
161114.40.0.0/18114.40.0.1 to 114.40.63.254114.40.63.25516,382
162114.40.64.0/18114.40.64.1 to 114.40.127.254114.40.127.25516,382
163114.40.128.0/18114.40.128.1 to 114.40.191.254114.40.191.25516,382
164114.40.192.0/18114.40.192.1 to 114.40.255.254114.40.255.25516,382
165114.41.0.0/18114.41.0.1 to 114.41.63.254114.41.63.25516,382
166114.41.64.0/18114.41.64.1 to 114.41.127.254114.41.127.25516,382
167114.41.128.0/18114.41.128.1 to 114.41.191.254114.41.191.25516,382
168114.41.192.0/18114.41.192.1 to 114.41.255.254114.41.255.25516,382
169114.42.0.0/18114.42.0.1 to 114.42.63.254114.42.63.25516,382
170114.42.64.0/18114.42.64.1 to 114.42.127.254114.42.127.25516,382
171114.42.128.0/18114.42.128.1 to 114.42.191.254114.42.191.25516,382
172114.42.192.0/18114.42.192.1 to 114.42.255.254114.42.255.25516,382
173114.43.0.0/18114.43.0.1 to 114.43.63.254114.43.63.25516,382
174114.43.64.0/18114.43.64.1 to 114.43.127.254114.43.127.25516,382
175114.43.128.0/18114.43.128.1 to 114.43.191.254114.43.191.25516,382
176114.43.192.0/18114.43.192.1 to 114.43.255.254114.43.255.25516,382
177114.44.0.0/18114.44.0.1 to 114.44.63.254114.44.63.25516,382
178114.44.64.0/18114.44.64.1 to 114.44.127.254114.44.127.25516,382
179114.44.128.0/18114.44.128.1 to 114.44.191.254114.44.191.25516,382
180114.44.192.0/18114.44.192.1 to 114.44.255.254114.44.255.25516,382
181114.45.0.0/18114.45.0.1 to 114.45.63.254114.45.63.25516,382
182114.45.64.0/18114.45.64.1 to 114.45.127.254114.45.127.25516,382
183114.45.128.0/18114.45.128.1 to 114.45.191.254114.45.191.25516,382
184114.45.192.0/18114.45.192.1 to 114.45.255.254114.45.255.25516,382
185114.46.0.0/18114.46.0.1 to 114.46.63.254114.46.63.25516,382
186114.46.64.0/18114.46.64.1 to 114.46.127.254114.46.127.25516,382
187114.46.128.0/18114.46.128.1 to 114.46.191.254114.46.191.25516,382
188114.46.192.0/18114.46.192.1 to 114.46.255.254114.46.255.25516,382
189114.47.0.0/18114.47.0.1 to 114.47.63.254114.47.63.25516,382
190114.47.64.0/18114.47.64.1 to 114.47.127.254114.47.127.25516,382
191114.47.128.0/18114.47.128.1 to 114.47.191.254114.47.191.25516,382
192114.47.192.0/18114.47.192.1 to 114.47.255.254114.47.255.25516,382
193114.48.0.0/18114.48.0.1 to 114.48.63.254114.48.63.25516,382
194114.48.64.0/18114.48.64.1 to 114.48.127.254114.48.127.25516,382
195114.48.128.0/18114.48.128.1 to 114.48.191.254114.48.191.25516,382
196114.48.192.0/18114.48.192.1 to 114.48.255.254114.48.255.25516,382
197114.49.0.0/18114.49.0.1 to 114.49.63.254114.49.63.25516,382
198114.49.64.0/18114.49.64.1 to 114.49.127.254114.49.127.25516,382
199114.49.128.0/18114.49.128.1 to 114.49.191.254114.49.191.25516,382
200114.49.192.0/18114.49.192.1 to 114.49.255.254114.49.255.25516,382
201114.50.0.0/18114.50.0.1 to 114.50.63.254114.50.63.25516,382
202114.50.64.0/18114.50.64.1 to 114.50.127.254114.50.127.25516,382
203114.50.128.0/18114.50.128.1 to 114.50.191.254114.50.191.25516,382
204114.50.192.0/18114.50.192.1 to 114.50.255.254114.50.255.25516,382
205114.51.0.0/18114.51.0.1 to 114.51.63.254114.51.63.25516,382
206114.51.64.0/18114.51.64.1 to 114.51.127.254114.51.127.25516,382
207114.51.128.0/18114.51.128.1 to 114.51.191.254114.51.191.25516,382
208114.51.192.0/18114.51.192.1 to 114.51.255.254114.51.255.25516,382
209114.52.0.0/18114.52.0.1 to 114.52.63.254114.52.63.25516,382
210114.52.64.0/18114.52.64.1 to 114.52.127.254114.52.127.25516,382
211114.52.128.0/18114.52.128.1 to 114.52.191.254114.52.191.25516,382
212114.52.192.0/18114.52.192.1 to 114.52.255.254114.52.255.25516,382
213114.53.0.0/18114.53.0.1 to 114.53.63.254114.53.63.25516,382
214114.53.64.0/18114.53.64.1 to 114.53.127.254114.53.127.25516,382
215114.53.128.0/18114.53.128.1 to 114.53.191.254114.53.191.25516,382
216114.53.192.0/18114.53.192.1 to 114.53.255.254114.53.255.25516,382
217114.54.0.0/18114.54.0.1 to 114.54.63.254114.54.63.25516,382
218114.54.64.0/18114.54.64.1 to 114.54.127.254114.54.127.25516,382
219114.54.128.0/18114.54.128.1 to 114.54.191.254114.54.191.25516,382
220114.54.192.0/18114.54.192.1 to 114.54.255.254114.54.255.25516,382
221114.55.0.0/18114.55.0.1 to 114.55.63.254114.55.63.25516,382
222114.55.64.0/18114.55.64.1 to 114.55.127.254114.55.127.25516,382
223114.55.128.0/18114.55.128.1 to 114.55.191.254114.55.191.25516,382
224114.55.192.0/18114.55.192.1 to 114.55.255.254114.55.255.25516,382
225114.56.0.0/18114.56.0.1 to 114.56.63.254114.56.63.25516,382
226114.56.64.0/18114.56.64.1 to 114.56.127.254114.56.127.25516,382
227114.56.128.0/18114.56.128.1 to 114.56.191.254114.56.191.25516,382
228114.56.192.0/18114.56.192.1 to 114.56.255.254114.56.255.25516,382
229114.57.0.0/18114.57.0.1 to 114.57.63.254114.57.63.25516,382
230114.57.64.0/18114.57.64.1 to 114.57.127.254114.57.127.25516,382
231114.57.128.0/18114.57.128.1 to 114.57.191.254114.57.191.25516,382
232114.57.192.0/18114.57.192.1 to 114.57.255.254114.57.255.25516,382
233114.58.0.0/18114.58.0.1 to 114.58.63.254114.58.63.25516,382
234114.58.64.0/18114.58.64.1 to 114.58.127.254114.58.127.25516,382
235114.58.128.0/18114.58.128.1 to 114.58.191.254114.58.191.25516,382
236114.58.192.0/18114.58.192.1 to 114.58.255.254114.58.255.25516,382
237114.59.0.0/18114.59.0.1 to 114.59.63.254114.59.63.25516,382
238114.59.64.0/18114.59.64.1 to 114.59.127.254114.59.127.25516,382
239114.59.128.0/18114.59.128.1 to 114.59.191.254114.59.191.25516,382
240114.59.192.0/18114.59.192.1 to 114.59.255.254114.59.255.25516,382
241114.60.0.0/18114.60.0.1 to 114.60.63.254114.60.63.25516,382
242114.60.64.0/18114.60.64.1 to 114.60.127.254114.60.127.25516,382
243114.60.128.0/18114.60.128.1 to 114.60.191.254114.60.191.25516,382
244114.60.192.0/18114.60.192.1 to 114.60.255.254114.60.255.25516,382
245114.61.0.0/18114.61.0.1 to 114.61.63.254114.61.63.25516,382
246114.61.64.0/18114.61.64.1 to 114.61.127.254114.61.127.25516,382
247114.61.128.0/18114.61.128.1 to 114.61.191.254114.61.191.25516,382
248114.61.192.0/18114.61.192.1 to 114.61.255.254114.61.255.25516,382
249114.62.0.0/18114.62.0.1 to 114.62.63.254114.62.63.25516,382
250114.62.64.0/18114.62.64.1 to 114.62.127.254114.62.127.25516,382
251114.62.128.0/18114.62.128.1 to 114.62.191.254114.62.191.25516,382
252114.62.192.0/18114.62.192.1 to 114.62.255.254114.62.255.25516,382
253114.63.0.0/18114.63.0.1 to 114.63.63.254114.63.63.25516,382
254114.63.64.0/18114.63.64.1 to 114.63.127.254114.63.127.25516,382
255114.63.128.0/18114.63.128.1 to 114.63.191.254114.63.191.25516,382
256114.63.192.0/18114.63.192.1 to 114.63.255.254114.63.255.25516,382

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.