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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/20
/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 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1114.0.0.0/20114.0.0.1 to 114.0.15.254114.0.15.2554,094
2114.0.16.0/20114.0.16.1 to 114.0.31.254114.0.31.2554,094
3114.0.32.0/20114.0.32.1 to 114.0.47.254114.0.47.2554,094
4114.0.48.0/20114.0.48.1 to 114.0.63.254114.0.63.2554,094
5114.0.64.0/20114.0.64.1 to 114.0.79.254114.0.79.2554,094
6114.0.80.0/20114.0.80.1 to 114.0.95.254114.0.95.2554,094
7114.0.96.0/20114.0.96.1 to 114.0.111.254114.0.111.2554,094
8114.0.112.0/20114.0.112.1 to 114.0.127.254114.0.127.2554,094
9114.0.128.0/20114.0.128.1 to 114.0.143.254114.0.143.2554,094
10114.0.144.0/20114.0.144.1 to 114.0.159.254114.0.159.2554,094
11114.0.160.0/20114.0.160.1 to 114.0.175.254114.0.175.2554,094
12114.0.176.0/20114.0.176.1 to 114.0.191.254114.0.191.2554,094
13114.0.192.0/20114.0.192.1 to 114.0.207.254114.0.207.2554,094
14114.0.208.0/20114.0.208.1 to 114.0.223.254114.0.223.2554,094
15114.0.224.0/20114.0.224.1 to 114.0.239.254114.0.239.2554,094
16114.0.240.0/20114.0.240.1 to 114.0.255.254114.0.255.2554,094
17114.1.0.0/20114.1.0.1 to 114.1.15.254114.1.15.2554,094
18114.1.16.0/20114.1.16.1 to 114.1.31.254114.1.31.2554,094
19114.1.32.0/20114.1.32.1 to 114.1.47.254114.1.47.2554,094
20114.1.48.0/20114.1.48.1 to 114.1.63.254114.1.63.2554,094
21114.1.64.0/20114.1.64.1 to 114.1.79.254114.1.79.2554,094
22114.1.80.0/20114.1.80.1 to 114.1.95.254114.1.95.2554,094
23114.1.96.0/20114.1.96.1 to 114.1.111.254114.1.111.2554,094
24114.1.112.0/20114.1.112.1 to 114.1.127.254114.1.127.2554,094
25114.1.128.0/20114.1.128.1 to 114.1.143.254114.1.143.2554,094
26114.1.144.0/20114.1.144.1 to 114.1.159.254114.1.159.2554,094
27114.1.160.0/20114.1.160.1 to 114.1.175.254114.1.175.2554,094
28114.1.176.0/20114.1.176.1 to 114.1.191.254114.1.191.2554,094
29114.1.192.0/20114.1.192.1 to 114.1.207.254114.1.207.2554,094
30114.1.208.0/20114.1.208.1 to 114.1.223.254114.1.223.2554,094
31114.1.224.0/20114.1.224.1 to 114.1.239.254114.1.239.2554,094
32114.1.240.0/20114.1.240.1 to 114.1.255.254114.1.255.2554,094
33114.2.0.0/20114.2.0.1 to 114.2.15.254114.2.15.2554,094
34114.2.16.0/20114.2.16.1 to 114.2.31.254114.2.31.2554,094
35114.2.32.0/20114.2.32.1 to 114.2.47.254114.2.47.2554,094
36114.2.48.0/20114.2.48.1 to 114.2.63.254114.2.63.2554,094
37114.2.64.0/20114.2.64.1 to 114.2.79.254114.2.79.2554,094
38114.2.80.0/20114.2.80.1 to 114.2.95.254114.2.95.2554,094
39114.2.96.0/20114.2.96.1 to 114.2.111.254114.2.111.2554,094
40114.2.112.0/20114.2.112.1 to 114.2.127.254114.2.127.2554,094
41114.2.128.0/20114.2.128.1 to 114.2.143.254114.2.143.2554,094
42114.2.144.0/20114.2.144.1 to 114.2.159.254114.2.159.2554,094
43114.2.160.0/20114.2.160.1 to 114.2.175.254114.2.175.2554,094
44114.2.176.0/20114.2.176.1 to 114.2.191.254114.2.191.2554,094
45114.2.192.0/20114.2.192.1 to 114.2.207.254114.2.207.2554,094
46114.2.208.0/20114.2.208.1 to 114.2.223.254114.2.223.2554,094
47114.2.224.0/20114.2.224.1 to 114.2.239.254114.2.239.2554,094
48114.2.240.0/20114.2.240.1 to 114.2.255.254114.2.255.2554,094
49114.3.0.0/20114.3.0.1 to 114.3.15.254114.3.15.2554,094
50114.3.16.0/20114.3.16.1 to 114.3.31.254114.3.31.2554,094
51114.3.32.0/20114.3.32.1 to 114.3.47.254114.3.47.2554,094
52114.3.48.0/20114.3.48.1 to 114.3.63.254114.3.63.2554,094
53114.3.64.0/20114.3.64.1 to 114.3.79.254114.3.79.2554,094
54114.3.80.0/20114.3.80.1 to 114.3.95.254114.3.95.2554,094
55114.3.96.0/20114.3.96.1 to 114.3.111.254114.3.111.2554,094
56114.3.112.0/20114.3.112.1 to 114.3.127.254114.3.127.2554,094
57114.3.128.0/20114.3.128.1 to 114.3.143.254114.3.143.2554,094
58114.3.144.0/20114.3.144.1 to 114.3.159.254114.3.159.2554,094
59114.3.160.0/20114.3.160.1 to 114.3.175.254114.3.175.2554,094
60114.3.176.0/20114.3.176.1 to 114.3.191.254114.3.191.2554,094
61114.3.192.0/20114.3.192.1 to 114.3.207.254114.3.207.2554,094
62114.3.208.0/20114.3.208.1 to 114.3.223.254114.3.223.2554,094
63114.3.224.0/20114.3.224.1 to 114.3.239.254114.3.239.2554,094
64114.3.240.0/20114.3.240.1 to 114.3.255.254114.3.255.2554,094
65114.4.0.0/20114.4.0.1 to 114.4.15.254114.4.15.2554,094
66114.4.16.0/20114.4.16.1 to 114.4.31.254114.4.31.2554,094
67114.4.32.0/20114.4.32.1 to 114.4.47.254114.4.47.2554,094
68114.4.48.0/20114.4.48.1 to 114.4.63.254114.4.63.2554,094
69114.4.64.0/20114.4.64.1 to 114.4.79.254114.4.79.2554,094
70114.4.80.0/20114.4.80.1 to 114.4.95.254114.4.95.2554,094
71114.4.96.0/20114.4.96.1 to 114.4.111.254114.4.111.2554,094
72114.4.112.0/20114.4.112.1 to 114.4.127.254114.4.127.2554,094
73114.4.128.0/20114.4.128.1 to 114.4.143.254114.4.143.2554,094
74114.4.144.0/20114.4.144.1 to 114.4.159.254114.4.159.2554,094
75114.4.160.0/20114.4.160.1 to 114.4.175.254114.4.175.2554,094
76114.4.176.0/20114.4.176.1 to 114.4.191.254114.4.191.2554,094
77114.4.192.0/20114.4.192.1 to 114.4.207.254114.4.207.2554,094
78114.4.208.0/20114.4.208.1 to 114.4.223.254114.4.223.2554,094
79114.4.224.0/20114.4.224.1 to 114.4.239.254114.4.239.2554,094
80114.4.240.0/20114.4.240.1 to 114.4.255.254114.4.255.2554,094
81114.5.0.0/20114.5.0.1 to 114.5.15.254114.5.15.2554,094
82114.5.16.0/20114.5.16.1 to 114.5.31.254114.5.31.2554,094
83114.5.32.0/20114.5.32.1 to 114.5.47.254114.5.47.2554,094
84114.5.48.0/20114.5.48.1 to 114.5.63.254114.5.63.2554,094
85114.5.64.0/20114.5.64.1 to 114.5.79.254114.5.79.2554,094
86114.5.80.0/20114.5.80.1 to 114.5.95.254114.5.95.2554,094
87114.5.96.0/20114.5.96.1 to 114.5.111.254114.5.111.2554,094
88114.5.112.0/20114.5.112.1 to 114.5.127.254114.5.127.2554,094
89114.5.128.0/20114.5.128.1 to 114.5.143.254114.5.143.2554,094
90114.5.144.0/20114.5.144.1 to 114.5.159.254114.5.159.2554,094
91114.5.160.0/20114.5.160.1 to 114.5.175.254114.5.175.2554,094
92114.5.176.0/20114.5.176.1 to 114.5.191.254114.5.191.2554,094
93114.5.192.0/20114.5.192.1 to 114.5.207.254114.5.207.2554,094
94114.5.208.0/20114.5.208.1 to 114.5.223.254114.5.223.2554,094
95114.5.224.0/20114.5.224.1 to 114.5.239.254114.5.239.2554,094
96114.5.240.0/20114.5.240.1 to 114.5.255.254114.5.255.2554,094
97114.6.0.0/20114.6.0.1 to 114.6.15.254114.6.15.2554,094
98114.6.16.0/20114.6.16.1 to 114.6.31.254114.6.31.2554,094
99114.6.32.0/20114.6.32.1 to 114.6.47.254114.6.47.2554,094
100114.6.48.0/20114.6.48.1 to 114.6.63.254114.6.63.2554,094
101114.6.64.0/20114.6.64.1 to 114.6.79.254114.6.79.2554,094
102114.6.80.0/20114.6.80.1 to 114.6.95.254114.6.95.2554,094
103114.6.96.0/20114.6.96.1 to 114.6.111.254114.6.111.2554,094
104114.6.112.0/20114.6.112.1 to 114.6.127.254114.6.127.2554,094
105114.6.128.0/20114.6.128.1 to 114.6.143.254114.6.143.2554,094
106114.6.144.0/20114.6.144.1 to 114.6.159.254114.6.159.2554,094
107114.6.160.0/20114.6.160.1 to 114.6.175.254114.6.175.2554,094
108114.6.176.0/20114.6.176.1 to 114.6.191.254114.6.191.2554,094
109114.6.192.0/20114.6.192.1 to 114.6.207.254114.6.207.2554,094
110114.6.208.0/20114.6.208.1 to 114.6.223.254114.6.223.2554,094
111114.6.224.0/20114.6.224.1 to 114.6.239.254114.6.239.2554,094
112114.6.240.0/20114.6.240.1 to 114.6.255.254114.6.255.2554,094
113114.7.0.0/20114.7.0.1 to 114.7.15.254114.7.15.2554,094
114114.7.16.0/20114.7.16.1 to 114.7.31.254114.7.31.2554,094
115114.7.32.0/20114.7.32.1 to 114.7.47.254114.7.47.2554,094
116114.7.48.0/20114.7.48.1 to 114.7.63.254114.7.63.2554,094
117114.7.64.0/20114.7.64.1 to 114.7.79.254114.7.79.2554,094
118114.7.80.0/20114.7.80.1 to 114.7.95.254114.7.95.2554,094
119114.7.96.0/20114.7.96.1 to 114.7.111.254114.7.111.2554,094
120114.7.112.0/20114.7.112.1 to 114.7.127.254114.7.127.2554,094
121114.7.128.0/20114.7.128.1 to 114.7.143.254114.7.143.2554,094
122114.7.144.0/20114.7.144.1 to 114.7.159.254114.7.159.2554,094
123114.7.160.0/20114.7.160.1 to 114.7.175.254114.7.175.2554,094
124114.7.176.0/20114.7.176.1 to 114.7.191.254114.7.191.2554,094
125114.7.192.0/20114.7.192.1 to 114.7.207.254114.7.207.2554,094
126114.7.208.0/20114.7.208.1 to 114.7.223.254114.7.223.2554,094
127114.7.224.0/20114.7.224.1 to 114.7.239.254114.7.239.2554,094
128114.7.240.0/20114.7.240.1 to 114.7.255.254114.7.255.2554,094
129114.8.0.0/20114.8.0.1 to 114.8.15.254114.8.15.2554,094
130114.8.16.0/20114.8.16.1 to 114.8.31.254114.8.31.2554,094
131114.8.32.0/20114.8.32.1 to 114.8.47.254114.8.47.2554,094
132114.8.48.0/20114.8.48.1 to 114.8.63.254114.8.63.2554,094
133114.8.64.0/20114.8.64.1 to 114.8.79.254114.8.79.2554,094
134114.8.80.0/20114.8.80.1 to 114.8.95.254114.8.95.2554,094
135114.8.96.0/20114.8.96.1 to 114.8.111.254114.8.111.2554,094
136114.8.112.0/20114.8.112.1 to 114.8.127.254114.8.127.2554,094
137114.8.128.0/20114.8.128.1 to 114.8.143.254114.8.143.2554,094
138114.8.144.0/20114.8.144.1 to 114.8.159.254114.8.159.2554,094
139114.8.160.0/20114.8.160.1 to 114.8.175.254114.8.175.2554,094
140114.8.176.0/20114.8.176.1 to 114.8.191.254114.8.191.2554,094
141114.8.192.0/20114.8.192.1 to 114.8.207.254114.8.207.2554,094
142114.8.208.0/20114.8.208.1 to 114.8.223.254114.8.223.2554,094
143114.8.224.0/20114.8.224.1 to 114.8.239.254114.8.239.2554,094
144114.8.240.0/20114.8.240.1 to 114.8.255.254114.8.255.2554,094
145114.9.0.0/20114.9.0.1 to 114.9.15.254114.9.15.2554,094
146114.9.16.0/20114.9.16.1 to 114.9.31.254114.9.31.2554,094
147114.9.32.0/20114.9.32.1 to 114.9.47.254114.9.47.2554,094
148114.9.48.0/20114.9.48.1 to 114.9.63.254114.9.63.2554,094
149114.9.64.0/20114.9.64.1 to 114.9.79.254114.9.79.2554,094
150114.9.80.0/20114.9.80.1 to 114.9.95.254114.9.95.2554,094
151114.9.96.0/20114.9.96.1 to 114.9.111.254114.9.111.2554,094
152114.9.112.0/20114.9.112.1 to 114.9.127.254114.9.127.2554,094
153114.9.128.0/20114.9.128.1 to 114.9.143.254114.9.143.2554,094
154114.9.144.0/20114.9.144.1 to 114.9.159.254114.9.159.2554,094
155114.9.160.0/20114.9.160.1 to 114.9.175.254114.9.175.2554,094
156114.9.176.0/20114.9.176.1 to 114.9.191.254114.9.191.2554,094
157114.9.192.0/20114.9.192.1 to 114.9.207.254114.9.207.2554,094
158114.9.208.0/20114.9.208.1 to 114.9.223.254114.9.223.2554,094
159114.9.224.0/20114.9.224.1 to 114.9.239.254114.9.239.2554,094
160114.9.240.0/20114.9.240.1 to 114.9.255.254114.9.255.2554,094
161114.10.0.0/20114.10.0.1 to 114.10.15.254114.10.15.2554,094
162114.10.16.0/20114.10.16.1 to 114.10.31.254114.10.31.2554,094
163114.10.32.0/20114.10.32.1 to 114.10.47.254114.10.47.2554,094
164114.10.48.0/20114.10.48.1 to 114.10.63.254114.10.63.2554,094
165114.10.64.0/20114.10.64.1 to 114.10.79.254114.10.79.2554,094
166114.10.80.0/20114.10.80.1 to 114.10.95.254114.10.95.2554,094
167114.10.96.0/20114.10.96.1 to 114.10.111.254114.10.111.2554,094
168114.10.112.0/20114.10.112.1 to 114.10.127.254114.10.127.2554,094
169114.10.128.0/20114.10.128.1 to 114.10.143.254114.10.143.2554,094
170114.10.144.0/20114.10.144.1 to 114.10.159.254114.10.159.2554,094
171114.10.160.0/20114.10.160.1 to 114.10.175.254114.10.175.2554,094
172114.10.176.0/20114.10.176.1 to 114.10.191.254114.10.191.2554,094
173114.10.192.0/20114.10.192.1 to 114.10.207.254114.10.207.2554,094
174114.10.208.0/20114.10.208.1 to 114.10.223.254114.10.223.2554,094
175114.10.224.0/20114.10.224.1 to 114.10.239.254114.10.239.2554,094
176114.10.240.0/20114.10.240.1 to 114.10.255.254114.10.255.2554,094
177114.11.0.0/20114.11.0.1 to 114.11.15.254114.11.15.2554,094
178114.11.16.0/20114.11.16.1 to 114.11.31.254114.11.31.2554,094
179114.11.32.0/20114.11.32.1 to 114.11.47.254114.11.47.2554,094
180114.11.48.0/20114.11.48.1 to 114.11.63.254114.11.63.2554,094
181114.11.64.0/20114.11.64.1 to 114.11.79.254114.11.79.2554,094
182114.11.80.0/20114.11.80.1 to 114.11.95.254114.11.95.2554,094
183114.11.96.0/20114.11.96.1 to 114.11.111.254114.11.111.2554,094
184114.11.112.0/20114.11.112.1 to 114.11.127.254114.11.127.2554,094
185114.11.128.0/20114.11.128.1 to 114.11.143.254114.11.143.2554,094
186114.11.144.0/20114.11.144.1 to 114.11.159.254114.11.159.2554,094
187114.11.160.0/20114.11.160.1 to 114.11.175.254114.11.175.2554,094
188114.11.176.0/20114.11.176.1 to 114.11.191.254114.11.191.2554,094
189114.11.192.0/20114.11.192.1 to 114.11.207.254114.11.207.2554,094
190114.11.208.0/20114.11.208.1 to 114.11.223.254114.11.223.2554,094
191114.11.224.0/20114.11.224.1 to 114.11.239.254114.11.239.2554,094
192114.11.240.0/20114.11.240.1 to 114.11.255.254114.11.255.2554,094
193114.12.0.0/20114.12.0.1 to 114.12.15.254114.12.15.2554,094
194114.12.16.0/20114.12.16.1 to 114.12.31.254114.12.31.2554,094
195114.12.32.0/20114.12.32.1 to 114.12.47.254114.12.47.2554,094
196114.12.48.0/20114.12.48.1 to 114.12.63.254114.12.63.2554,094
197114.12.64.0/20114.12.64.1 to 114.12.79.254114.12.79.2554,094
198114.12.80.0/20114.12.80.1 to 114.12.95.254114.12.95.2554,094
199114.12.96.0/20114.12.96.1 to 114.12.111.254114.12.111.2554,094
200114.12.112.0/20114.12.112.1 to 114.12.127.254114.12.127.2554,094
201114.12.128.0/20114.12.128.1 to 114.12.143.254114.12.143.2554,094
202114.12.144.0/20114.12.144.1 to 114.12.159.254114.12.159.2554,094
203114.12.160.0/20114.12.160.1 to 114.12.175.254114.12.175.2554,094
204114.12.176.0/20114.12.176.1 to 114.12.191.254114.12.191.2554,094
205114.12.192.0/20114.12.192.1 to 114.12.207.254114.12.207.2554,094
206114.12.208.0/20114.12.208.1 to 114.12.223.254114.12.223.2554,094
207114.12.224.0/20114.12.224.1 to 114.12.239.254114.12.239.2554,094
208114.12.240.0/20114.12.240.1 to 114.12.255.254114.12.255.2554,094
209114.13.0.0/20114.13.0.1 to 114.13.15.254114.13.15.2554,094
210114.13.16.0/20114.13.16.1 to 114.13.31.254114.13.31.2554,094
211114.13.32.0/20114.13.32.1 to 114.13.47.254114.13.47.2554,094
212114.13.48.0/20114.13.48.1 to 114.13.63.254114.13.63.2554,094
213114.13.64.0/20114.13.64.1 to 114.13.79.254114.13.79.2554,094
214114.13.80.0/20114.13.80.1 to 114.13.95.254114.13.95.2554,094
215114.13.96.0/20114.13.96.1 to 114.13.111.254114.13.111.2554,094
216114.13.112.0/20114.13.112.1 to 114.13.127.254114.13.127.2554,094
217114.13.128.0/20114.13.128.1 to 114.13.143.254114.13.143.2554,094
218114.13.144.0/20114.13.144.1 to 114.13.159.254114.13.159.2554,094
219114.13.160.0/20114.13.160.1 to 114.13.175.254114.13.175.2554,094
220114.13.176.0/20114.13.176.1 to 114.13.191.254114.13.191.2554,094
221114.13.192.0/20114.13.192.1 to 114.13.207.254114.13.207.2554,094
222114.13.208.0/20114.13.208.1 to 114.13.223.254114.13.223.2554,094
223114.13.224.0/20114.13.224.1 to 114.13.239.254114.13.239.2554,094
224114.13.240.0/20114.13.240.1 to 114.13.255.254114.13.255.2554,094
225114.14.0.0/20114.14.0.1 to 114.14.15.254114.14.15.2554,094
226114.14.16.0/20114.14.16.1 to 114.14.31.254114.14.31.2554,094
227114.14.32.0/20114.14.32.1 to 114.14.47.254114.14.47.2554,094
228114.14.48.0/20114.14.48.1 to 114.14.63.254114.14.63.2554,094
229114.14.64.0/20114.14.64.1 to 114.14.79.254114.14.79.2554,094
230114.14.80.0/20114.14.80.1 to 114.14.95.254114.14.95.2554,094
231114.14.96.0/20114.14.96.1 to 114.14.111.254114.14.111.2554,094
232114.14.112.0/20114.14.112.1 to 114.14.127.254114.14.127.2554,094
233114.14.128.0/20114.14.128.1 to 114.14.143.254114.14.143.2554,094
234114.14.144.0/20114.14.144.1 to 114.14.159.254114.14.159.2554,094
235114.14.160.0/20114.14.160.1 to 114.14.175.254114.14.175.2554,094
236114.14.176.0/20114.14.176.1 to 114.14.191.254114.14.191.2554,094
237114.14.192.0/20114.14.192.1 to 114.14.207.254114.14.207.2554,094
238114.14.208.0/20114.14.208.1 to 114.14.223.254114.14.223.2554,094
239114.14.224.0/20114.14.224.1 to 114.14.239.254114.14.239.2554,094
240114.14.240.0/20114.14.240.1 to 114.14.255.254114.14.255.2554,094
241114.15.0.0/20114.15.0.1 to 114.15.15.254114.15.15.2554,094
242114.15.16.0/20114.15.16.1 to 114.15.31.254114.15.31.2554,094
243114.15.32.0/20114.15.32.1 to 114.15.47.254114.15.47.2554,094
244114.15.48.0/20114.15.48.1 to 114.15.63.254114.15.63.2554,094
245114.15.64.0/20114.15.64.1 to 114.15.79.254114.15.79.2554,094
246114.15.80.0/20114.15.80.1 to 114.15.95.254114.15.95.2554,094
247114.15.96.0/20114.15.96.1 to 114.15.111.254114.15.111.2554,094
248114.15.112.0/20114.15.112.1 to 114.15.127.254114.15.127.2554,094
249114.15.128.0/20114.15.128.1 to 114.15.143.254114.15.143.2554,094
250114.15.144.0/20114.15.144.1 to 114.15.159.254114.15.159.2554,094
251114.15.160.0/20114.15.160.1 to 114.15.175.254114.15.175.2554,094
252114.15.176.0/20114.15.176.1 to 114.15.191.254114.15.191.2554,094
253114.15.192.0/20114.15.192.1 to 114.15.207.254114.15.207.2554,094
254114.15.208.0/20114.15.208.1 to 114.15.223.254114.15.223.2554,094
255114.15.224.0/20114.15.224.1 to 114.15.239.254114.15.239.2554,094
256114.15.240.0/20114.15.240.1 to 114.15.255.254114.15.255.2554,094

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.