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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.

Network112.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
112.0.0.0
Broadcast address
112.255.255.255
First usable
112.0.0.1
Last usable
112.255.255.254
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 70000000 · Integer 1879048192 to 1895825407
Reverse DNS zone
112.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110000..00000000.00000000.00000000112.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01110000..00000000.00000000.00000000112.0.0.0
Broadcast01110000..11111111.11111111.11111111112.255.255.255
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)

112.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1112.0.0.0/20112.0.0.1 to 112.0.15.254112.0.15.2554,094
2112.0.16.0/20112.0.16.1 to 112.0.31.254112.0.31.2554,094
3112.0.32.0/20112.0.32.1 to 112.0.47.254112.0.47.2554,094
4112.0.48.0/20112.0.48.1 to 112.0.63.254112.0.63.2554,094
5112.0.64.0/20112.0.64.1 to 112.0.79.254112.0.79.2554,094
6112.0.80.0/20112.0.80.1 to 112.0.95.254112.0.95.2554,094
7112.0.96.0/20112.0.96.1 to 112.0.111.254112.0.111.2554,094
8112.0.112.0/20112.0.112.1 to 112.0.127.254112.0.127.2554,094
9112.0.128.0/20112.0.128.1 to 112.0.143.254112.0.143.2554,094
10112.0.144.0/20112.0.144.1 to 112.0.159.254112.0.159.2554,094
11112.0.160.0/20112.0.160.1 to 112.0.175.254112.0.175.2554,094
12112.0.176.0/20112.0.176.1 to 112.0.191.254112.0.191.2554,094
13112.0.192.0/20112.0.192.1 to 112.0.207.254112.0.207.2554,094
14112.0.208.0/20112.0.208.1 to 112.0.223.254112.0.223.2554,094
15112.0.224.0/20112.0.224.1 to 112.0.239.254112.0.239.2554,094
16112.0.240.0/20112.0.240.1 to 112.0.255.254112.0.255.2554,094
17112.1.0.0/20112.1.0.1 to 112.1.15.254112.1.15.2554,094
18112.1.16.0/20112.1.16.1 to 112.1.31.254112.1.31.2554,094
19112.1.32.0/20112.1.32.1 to 112.1.47.254112.1.47.2554,094
20112.1.48.0/20112.1.48.1 to 112.1.63.254112.1.63.2554,094
21112.1.64.0/20112.1.64.1 to 112.1.79.254112.1.79.2554,094
22112.1.80.0/20112.1.80.1 to 112.1.95.254112.1.95.2554,094
23112.1.96.0/20112.1.96.1 to 112.1.111.254112.1.111.2554,094
24112.1.112.0/20112.1.112.1 to 112.1.127.254112.1.127.2554,094
25112.1.128.0/20112.1.128.1 to 112.1.143.254112.1.143.2554,094
26112.1.144.0/20112.1.144.1 to 112.1.159.254112.1.159.2554,094
27112.1.160.0/20112.1.160.1 to 112.1.175.254112.1.175.2554,094
28112.1.176.0/20112.1.176.1 to 112.1.191.254112.1.191.2554,094
29112.1.192.0/20112.1.192.1 to 112.1.207.254112.1.207.2554,094
30112.1.208.0/20112.1.208.1 to 112.1.223.254112.1.223.2554,094
31112.1.224.0/20112.1.224.1 to 112.1.239.254112.1.239.2554,094
32112.1.240.0/20112.1.240.1 to 112.1.255.254112.1.255.2554,094
33112.2.0.0/20112.2.0.1 to 112.2.15.254112.2.15.2554,094
34112.2.16.0/20112.2.16.1 to 112.2.31.254112.2.31.2554,094
35112.2.32.0/20112.2.32.1 to 112.2.47.254112.2.47.2554,094
36112.2.48.0/20112.2.48.1 to 112.2.63.254112.2.63.2554,094
37112.2.64.0/20112.2.64.1 to 112.2.79.254112.2.79.2554,094
38112.2.80.0/20112.2.80.1 to 112.2.95.254112.2.95.2554,094
39112.2.96.0/20112.2.96.1 to 112.2.111.254112.2.111.2554,094
40112.2.112.0/20112.2.112.1 to 112.2.127.254112.2.127.2554,094
41112.2.128.0/20112.2.128.1 to 112.2.143.254112.2.143.2554,094
42112.2.144.0/20112.2.144.1 to 112.2.159.254112.2.159.2554,094
43112.2.160.0/20112.2.160.1 to 112.2.175.254112.2.175.2554,094
44112.2.176.0/20112.2.176.1 to 112.2.191.254112.2.191.2554,094
45112.2.192.0/20112.2.192.1 to 112.2.207.254112.2.207.2554,094
46112.2.208.0/20112.2.208.1 to 112.2.223.254112.2.223.2554,094
47112.2.224.0/20112.2.224.1 to 112.2.239.254112.2.239.2554,094
48112.2.240.0/20112.2.240.1 to 112.2.255.254112.2.255.2554,094
49112.3.0.0/20112.3.0.1 to 112.3.15.254112.3.15.2554,094
50112.3.16.0/20112.3.16.1 to 112.3.31.254112.3.31.2554,094
51112.3.32.0/20112.3.32.1 to 112.3.47.254112.3.47.2554,094
52112.3.48.0/20112.3.48.1 to 112.3.63.254112.3.63.2554,094
53112.3.64.0/20112.3.64.1 to 112.3.79.254112.3.79.2554,094
54112.3.80.0/20112.3.80.1 to 112.3.95.254112.3.95.2554,094
55112.3.96.0/20112.3.96.1 to 112.3.111.254112.3.111.2554,094
56112.3.112.0/20112.3.112.1 to 112.3.127.254112.3.127.2554,094
57112.3.128.0/20112.3.128.1 to 112.3.143.254112.3.143.2554,094
58112.3.144.0/20112.3.144.1 to 112.3.159.254112.3.159.2554,094
59112.3.160.0/20112.3.160.1 to 112.3.175.254112.3.175.2554,094
60112.3.176.0/20112.3.176.1 to 112.3.191.254112.3.191.2554,094
61112.3.192.0/20112.3.192.1 to 112.3.207.254112.3.207.2554,094
62112.3.208.0/20112.3.208.1 to 112.3.223.254112.3.223.2554,094
63112.3.224.0/20112.3.224.1 to 112.3.239.254112.3.239.2554,094
64112.3.240.0/20112.3.240.1 to 112.3.255.254112.3.255.2554,094
65112.4.0.0/20112.4.0.1 to 112.4.15.254112.4.15.2554,094
66112.4.16.0/20112.4.16.1 to 112.4.31.254112.4.31.2554,094
67112.4.32.0/20112.4.32.1 to 112.4.47.254112.4.47.2554,094
68112.4.48.0/20112.4.48.1 to 112.4.63.254112.4.63.2554,094
69112.4.64.0/20112.4.64.1 to 112.4.79.254112.4.79.2554,094
70112.4.80.0/20112.4.80.1 to 112.4.95.254112.4.95.2554,094
71112.4.96.0/20112.4.96.1 to 112.4.111.254112.4.111.2554,094
72112.4.112.0/20112.4.112.1 to 112.4.127.254112.4.127.2554,094
73112.4.128.0/20112.4.128.1 to 112.4.143.254112.4.143.2554,094
74112.4.144.0/20112.4.144.1 to 112.4.159.254112.4.159.2554,094
75112.4.160.0/20112.4.160.1 to 112.4.175.254112.4.175.2554,094
76112.4.176.0/20112.4.176.1 to 112.4.191.254112.4.191.2554,094
77112.4.192.0/20112.4.192.1 to 112.4.207.254112.4.207.2554,094
78112.4.208.0/20112.4.208.1 to 112.4.223.254112.4.223.2554,094
79112.4.224.0/20112.4.224.1 to 112.4.239.254112.4.239.2554,094
80112.4.240.0/20112.4.240.1 to 112.4.255.254112.4.255.2554,094
81112.5.0.0/20112.5.0.1 to 112.5.15.254112.5.15.2554,094
82112.5.16.0/20112.5.16.1 to 112.5.31.254112.5.31.2554,094
83112.5.32.0/20112.5.32.1 to 112.5.47.254112.5.47.2554,094
84112.5.48.0/20112.5.48.1 to 112.5.63.254112.5.63.2554,094
85112.5.64.0/20112.5.64.1 to 112.5.79.254112.5.79.2554,094
86112.5.80.0/20112.5.80.1 to 112.5.95.254112.5.95.2554,094
87112.5.96.0/20112.5.96.1 to 112.5.111.254112.5.111.2554,094
88112.5.112.0/20112.5.112.1 to 112.5.127.254112.5.127.2554,094
89112.5.128.0/20112.5.128.1 to 112.5.143.254112.5.143.2554,094
90112.5.144.0/20112.5.144.1 to 112.5.159.254112.5.159.2554,094
91112.5.160.0/20112.5.160.1 to 112.5.175.254112.5.175.2554,094
92112.5.176.0/20112.5.176.1 to 112.5.191.254112.5.191.2554,094
93112.5.192.0/20112.5.192.1 to 112.5.207.254112.5.207.2554,094
94112.5.208.0/20112.5.208.1 to 112.5.223.254112.5.223.2554,094
95112.5.224.0/20112.5.224.1 to 112.5.239.254112.5.239.2554,094
96112.5.240.0/20112.5.240.1 to 112.5.255.254112.5.255.2554,094
97112.6.0.0/20112.6.0.1 to 112.6.15.254112.6.15.2554,094
98112.6.16.0/20112.6.16.1 to 112.6.31.254112.6.31.2554,094
99112.6.32.0/20112.6.32.1 to 112.6.47.254112.6.47.2554,094
100112.6.48.0/20112.6.48.1 to 112.6.63.254112.6.63.2554,094
101112.6.64.0/20112.6.64.1 to 112.6.79.254112.6.79.2554,094
102112.6.80.0/20112.6.80.1 to 112.6.95.254112.6.95.2554,094
103112.6.96.0/20112.6.96.1 to 112.6.111.254112.6.111.2554,094
104112.6.112.0/20112.6.112.1 to 112.6.127.254112.6.127.2554,094
105112.6.128.0/20112.6.128.1 to 112.6.143.254112.6.143.2554,094
106112.6.144.0/20112.6.144.1 to 112.6.159.254112.6.159.2554,094
107112.6.160.0/20112.6.160.1 to 112.6.175.254112.6.175.2554,094
108112.6.176.0/20112.6.176.1 to 112.6.191.254112.6.191.2554,094
109112.6.192.0/20112.6.192.1 to 112.6.207.254112.6.207.2554,094
110112.6.208.0/20112.6.208.1 to 112.6.223.254112.6.223.2554,094
111112.6.224.0/20112.6.224.1 to 112.6.239.254112.6.239.2554,094
112112.6.240.0/20112.6.240.1 to 112.6.255.254112.6.255.2554,094
113112.7.0.0/20112.7.0.1 to 112.7.15.254112.7.15.2554,094
114112.7.16.0/20112.7.16.1 to 112.7.31.254112.7.31.2554,094
115112.7.32.0/20112.7.32.1 to 112.7.47.254112.7.47.2554,094
116112.7.48.0/20112.7.48.1 to 112.7.63.254112.7.63.2554,094
117112.7.64.0/20112.7.64.1 to 112.7.79.254112.7.79.2554,094
118112.7.80.0/20112.7.80.1 to 112.7.95.254112.7.95.2554,094
119112.7.96.0/20112.7.96.1 to 112.7.111.254112.7.111.2554,094
120112.7.112.0/20112.7.112.1 to 112.7.127.254112.7.127.2554,094
121112.7.128.0/20112.7.128.1 to 112.7.143.254112.7.143.2554,094
122112.7.144.0/20112.7.144.1 to 112.7.159.254112.7.159.2554,094
123112.7.160.0/20112.7.160.1 to 112.7.175.254112.7.175.2554,094
124112.7.176.0/20112.7.176.1 to 112.7.191.254112.7.191.2554,094
125112.7.192.0/20112.7.192.1 to 112.7.207.254112.7.207.2554,094
126112.7.208.0/20112.7.208.1 to 112.7.223.254112.7.223.2554,094
127112.7.224.0/20112.7.224.1 to 112.7.239.254112.7.239.2554,094
128112.7.240.0/20112.7.240.1 to 112.7.255.254112.7.255.2554,094
129112.8.0.0/20112.8.0.1 to 112.8.15.254112.8.15.2554,094
130112.8.16.0/20112.8.16.1 to 112.8.31.254112.8.31.2554,094
131112.8.32.0/20112.8.32.1 to 112.8.47.254112.8.47.2554,094
132112.8.48.0/20112.8.48.1 to 112.8.63.254112.8.63.2554,094
133112.8.64.0/20112.8.64.1 to 112.8.79.254112.8.79.2554,094
134112.8.80.0/20112.8.80.1 to 112.8.95.254112.8.95.2554,094
135112.8.96.0/20112.8.96.1 to 112.8.111.254112.8.111.2554,094
136112.8.112.0/20112.8.112.1 to 112.8.127.254112.8.127.2554,094
137112.8.128.0/20112.8.128.1 to 112.8.143.254112.8.143.2554,094
138112.8.144.0/20112.8.144.1 to 112.8.159.254112.8.159.2554,094
139112.8.160.0/20112.8.160.1 to 112.8.175.254112.8.175.2554,094
140112.8.176.0/20112.8.176.1 to 112.8.191.254112.8.191.2554,094
141112.8.192.0/20112.8.192.1 to 112.8.207.254112.8.207.2554,094
142112.8.208.0/20112.8.208.1 to 112.8.223.254112.8.223.2554,094
143112.8.224.0/20112.8.224.1 to 112.8.239.254112.8.239.2554,094
144112.8.240.0/20112.8.240.1 to 112.8.255.254112.8.255.2554,094
145112.9.0.0/20112.9.0.1 to 112.9.15.254112.9.15.2554,094
146112.9.16.0/20112.9.16.1 to 112.9.31.254112.9.31.2554,094
147112.9.32.0/20112.9.32.1 to 112.9.47.254112.9.47.2554,094
148112.9.48.0/20112.9.48.1 to 112.9.63.254112.9.63.2554,094
149112.9.64.0/20112.9.64.1 to 112.9.79.254112.9.79.2554,094
150112.9.80.0/20112.9.80.1 to 112.9.95.254112.9.95.2554,094
151112.9.96.0/20112.9.96.1 to 112.9.111.254112.9.111.2554,094
152112.9.112.0/20112.9.112.1 to 112.9.127.254112.9.127.2554,094
153112.9.128.0/20112.9.128.1 to 112.9.143.254112.9.143.2554,094
154112.9.144.0/20112.9.144.1 to 112.9.159.254112.9.159.2554,094
155112.9.160.0/20112.9.160.1 to 112.9.175.254112.9.175.2554,094
156112.9.176.0/20112.9.176.1 to 112.9.191.254112.9.191.2554,094
157112.9.192.0/20112.9.192.1 to 112.9.207.254112.9.207.2554,094
158112.9.208.0/20112.9.208.1 to 112.9.223.254112.9.223.2554,094
159112.9.224.0/20112.9.224.1 to 112.9.239.254112.9.239.2554,094
160112.9.240.0/20112.9.240.1 to 112.9.255.254112.9.255.2554,094
161112.10.0.0/20112.10.0.1 to 112.10.15.254112.10.15.2554,094
162112.10.16.0/20112.10.16.1 to 112.10.31.254112.10.31.2554,094
163112.10.32.0/20112.10.32.1 to 112.10.47.254112.10.47.2554,094
164112.10.48.0/20112.10.48.1 to 112.10.63.254112.10.63.2554,094
165112.10.64.0/20112.10.64.1 to 112.10.79.254112.10.79.2554,094
166112.10.80.0/20112.10.80.1 to 112.10.95.254112.10.95.2554,094
167112.10.96.0/20112.10.96.1 to 112.10.111.254112.10.111.2554,094
168112.10.112.0/20112.10.112.1 to 112.10.127.254112.10.127.2554,094
169112.10.128.0/20112.10.128.1 to 112.10.143.254112.10.143.2554,094
170112.10.144.0/20112.10.144.1 to 112.10.159.254112.10.159.2554,094
171112.10.160.0/20112.10.160.1 to 112.10.175.254112.10.175.2554,094
172112.10.176.0/20112.10.176.1 to 112.10.191.254112.10.191.2554,094
173112.10.192.0/20112.10.192.1 to 112.10.207.254112.10.207.2554,094
174112.10.208.0/20112.10.208.1 to 112.10.223.254112.10.223.2554,094
175112.10.224.0/20112.10.224.1 to 112.10.239.254112.10.239.2554,094
176112.10.240.0/20112.10.240.1 to 112.10.255.254112.10.255.2554,094
177112.11.0.0/20112.11.0.1 to 112.11.15.254112.11.15.2554,094
178112.11.16.0/20112.11.16.1 to 112.11.31.254112.11.31.2554,094
179112.11.32.0/20112.11.32.1 to 112.11.47.254112.11.47.2554,094
180112.11.48.0/20112.11.48.1 to 112.11.63.254112.11.63.2554,094
181112.11.64.0/20112.11.64.1 to 112.11.79.254112.11.79.2554,094
182112.11.80.0/20112.11.80.1 to 112.11.95.254112.11.95.2554,094
183112.11.96.0/20112.11.96.1 to 112.11.111.254112.11.111.2554,094
184112.11.112.0/20112.11.112.1 to 112.11.127.254112.11.127.2554,094
185112.11.128.0/20112.11.128.1 to 112.11.143.254112.11.143.2554,094
186112.11.144.0/20112.11.144.1 to 112.11.159.254112.11.159.2554,094
187112.11.160.0/20112.11.160.1 to 112.11.175.254112.11.175.2554,094
188112.11.176.0/20112.11.176.1 to 112.11.191.254112.11.191.2554,094
189112.11.192.0/20112.11.192.1 to 112.11.207.254112.11.207.2554,094
190112.11.208.0/20112.11.208.1 to 112.11.223.254112.11.223.2554,094
191112.11.224.0/20112.11.224.1 to 112.11.239.254112.11.239.2554,094
192112.11.240.0/20112.11.240.1 to 112.11.255.254112.11.255.2554,094
193112.12.0.0/20112.12.0.1 to 112.12.15.254112.12.15.2554,094
194112.12.16.0/20112.12.16.1 to 112.12.31.254112.12.31.2554,094
195112.12.32.0/20112.12.32.1 to 112.12.47.254112.12.47.2554,094
196112.12.48.0/20112.12.48.1 to 112.12.63.254112.12.63.2554,094
197112.12.64.0/20112.12.64.1 to 112.12.79.254112.12.79.2554,094
198112.12.80.0/20112.12.80.1 to 112.12.95.254112.12.95.2554,094
199112.12.96.0/20112.12.96.1 to 112.12.111.254112.12.111.2554,094
200112.12.112.0/20112.12.112.1 to 112.12.127.254112.12.127.2554,094
201112.12.128.0/20112.12.128.1 to 112.12.143.254112.12.143.2554,094
202112.12.144.0/20112.12.144.1 to 112.12.159.254112.12.159.2554,094
203112.12.160.0/20112.12.160.1 to 112.12.175.254112.12.175.2554,094
204112.12.176.0/20112.12.176.1 to 112.12.191.254112.12.191.2554,094
205112.12.192.0/20112.12.192.1 to 112.12.207.254112.12.207.2554,094
206112.12.208.0/20112.12.208.1 to 112.12.223.254112.12.223.2554,094
207112.12.224.0/20112.12.224.1 to 112.12.239.254112.12.239.2554,094
208112.12.240.0/20112.12.240.1 to 112.12.255.254112.12.255.2554,094
209112.13.0.0/20112.13.0.1 to 112.13.15.254112.13.15.2554,094
210112.13.16.0/20112.13.16.1 to 112.13.31.254112.13.31.2554,094
211112.13.32.0/20112.13.32.1 to 112.13.47.254112.13.47.2554,094
212112.13.48.0/20112.13.48.1 to 112.13.63.254112.13.63.2554,094
213112.13.64.0/20112.13.64.1 to 112.13.79.254112.13.79.2554,094
214112.13.80.0/20112.13.80.1 to 112.13.95.254112.13.95.2554,094
215112.13.96.0/20112.13.96.1 to 112.13.111.254112.13.111.2554,094
216112.13.112.0/20112.13.112.1 to 112.13.127.254112.13.127.2554,094
217112.13.128.0/20112.13.128.1 to 112.13.143.254112.13.143.2554,094
218112.13.144.0/20112.13.144.1 to 112.13.159.254112.13.159.2554,094
219112.13.160.0/20112.13.160.1 to 112.13.175.254112.13.175.2554,094
220112.13.176.0/20112.13.176.1 to 112.13.191.254112.13.191.2554,094
221112.13.192.0/20112.13.192.1 to 112.13.207.254112.13.207.2554,094
222112.13.208.0/20112.13.208.1 to 112.13.223.254112.13.223.2554,094
223112.13.224.0/20112.13.224.1 to 112.13.239.254112.13.239.2554,094
224112.13.240.0/20112.13.240.1 to 112.13.255.254112.13.255.2554,094
225112.14.0.0/20112.14.0.1 to 112.14.15.254112.14.15.2554,094
226112.14.16.0/20112.14.16.1 to 112.14.31.254112.14.31.2554,094
227112.14.32.0/20112.14.32.1 to 112.14.47.254112.14.47.2554,094
228112.14.48.0/20112.14.48.1 to 112.14.63.254112.14.63.2554,094
229112.14.64.0/20112.14.64.1 to 112.14.79.254112.14.79.2554,094
230112.14.80.0/20112.14.80.1 to 112.14.95.254112.14.95.2554,094
231112.14.96.0/20112.14.96.1 to 112.14.111.254112.14.111.2554,094
232112.14.112.0/20112.14.112.1 to 112.14.127.254112.14.127.2554,094
233112.14.128.0/20112.14.128.1 to 112.14.143.254112.14.143.2554,094
234112.14.144.0/20112.14.144.1 to 112.14.159.254112.14.159.2554,094
235112.14.160.0/20112.14.160.1 to 112.14.175.254112.14.175.2554,094
236112.14.176.0/20112.14.176.1 to 112.14.191.254112.14.191.2554,094
237112.14.192.0/20112.14.192.1 to 112.14.207.254112.14.207.2554,094
238112.14.208.0/20112.14.208.1 to 112.14.223.254112.14.223.2554,094
239112.14.224.0/20112.14.224.1 to 112.14.239.254112.14.239.2554,094
240112.14.240.0/20112.14.240.1 to 112.14.255.254112.14.255.2554,094
241112.15.0.0/20112.15.0.1 to 112.15.15.254112.15.15.2554,094
242112.15.16.0/20112.15.16.1 to 112.15.31.254112.15.31.2554,094
243112.15.32.0/20112.15.32.1 to 112.15.47.254112.15.47.2554,094
244112.15.48.0/20112.15.48.1 to 112.15.63.254112.15.63.2554,094
245112.15.64.0/20112.15.64.1 to 112.15.79.254112.15.79.2554,094
246112.15.80.0/20112.15.80.1 to 112.15.95.254112.15.95.2554,094
247112.15.96.0/20112.15.96.1 to 112.15.111.254112.15.111.2554,094
248112.15.112.0/20112.15.112.1 to 112.15.127.254112.15.127.2554,094
249112.15.128.0/20112.15.128.1 to 112.15.143.254112.15.143.2554,094
250112.15.144.0/20112.15.144.1 to 112.15.159.254112.15.159.2554,094
251112.15.160.0/20112.15.160.1 to 112.15.175.254112.15.175.2554,094
252112.15.176.0/20112.15.176.1 to 112.15.191.254112.15.191.2554,094
253112.15.192.0/20112.15.192.1 to 112.15.207.254112.15.207.2554,094
254112.15.208.0/20112.15.208.1 to 112.15.223.254112.15.223.2554,094
255112.15.224.0/20112.15.224.1 to 112.15.239.254112.15.239.2554,094
256112.15.240.0/20112.15.240.1 to 112.15.255.254112.15.255.2554,094

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.