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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.

Network112.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
112.0.0.0
Broadcast address
112.127.255.255
First usable
112.0.0.1
Last usable
112.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 70000000 · Integer 1879048192 to 1887436799
Reverse DNS zones
0.112.in-addr.arpa
1.112.in-addr.arpa
2.112.in-addr.arpa
3.112.in-addr.arpa
4.112.in-addr.arpa
5.112.in-addr.arpa
6.112.in-addr.arpa
7.112.in-addr.arpa
8.112.in-addr.arpa
9.112.in-addr.arpa
10.112.in-addr.arpa
11.112.in-addr.arpa
12.112.in-addr.arpa
13.112.in-addr.arpa
14.112.in-addr.arpa
15.112.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110000.00000000.00000000.00000000112.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01110000.00000000.00000000.00000000112.0.0.0
Broadcast01110000.01111111.11111111.11111111112.127.255.255
Split into smaller subnets/18
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

112.0.0.0/9 makes 512 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1112.0.0.0/18112.0.0.1 to 112.0.63.254112.0.63.25516,382
2112.0.64.0/18112.0.64.1 to 112.0.127.254112.0.127.25516,382
3112.0.128.0/18112.0.128.1 to 112.0.191.254112.0.191.25516,382
4112.0.192.0/18112.0.192.1 to 112.0.255.254112.0.255.25516,382
5112.1.0.0/18112.1.0.1 to 112.1.63.254112.1.63.25516,382
6112.1.64.0/18112.1.64.1 to 112.1.127.254112.1.127.25516,382
7112.1.128.0/18112.1.128.1 to 112.1.191.254112.1.191.25516,382
8112.1.192.0/18112.1.192.1 to 112.1.255.254112.1.255.25516,382
9112.2.0.0/18112.2.0.1 to 112.2.63.254112.2.63.25516,382
10112.2.64.0/18112.2.64.1 to 112.2.127.254112.2.127.25516,382
11112.2.128.0/18112.2.128.1 to 112.2.191.254112.2.191.25516,382
12112.2.192.0/18112.2.192.1 to 112.2.255.254112.2.255.25516,382
13112.3.0.0/18112.3.0.1 to 112.3.63.254112.3.63.25516,382
14112.3.64.0/18112.3.64.1 to 112.3.127.254112.3.127.25516,382
15112.3.128.0/18112.3.128.1 to 112.3.191.254112.3.191.25516,382
16112.3.192.0/18112.3.192.1 to 112.3.255.254112.3.255.25516,382
17112.4.0.0/18112.4.0.1 to 112.4.63.254112.4.63.25516,382
18112.4.64.0/18112.4.64.1 to 112.4.127.254112.4.127.25516,382
19112.4.128.0/18112.4.128.1 to 112.4.191.254112.4.191.25516,382
20112.4.192.0/18112.4.192.1 to 112.4.255.254112.4.255.25516,382
21112.5.0.0/18112.5.0.1 to 112.5.63.254112.5.63.25516,382
22112.5.64.0/18112.5.64.1 to 112.5.127.254112.5.127.25516,382
23112.5.128.0/18112.5.128.1 to 112.5.191.254112.5.191.25516,382
24112.5.192.0/18112.5.192.1 to 112.5.255.254112.5.255.25516,382
25112.6.0.0/18112.6.0.1 to 112.6.63.254112.6.63.25516,382
26112.6.64.0/18112.6.64.1 to 112.6.127.254112.6.127.25516,382
27112.6.128.0/18112.6.128.1 to 112.6.191.254112.6.191.25516,382
28112.6.192.0/18112.6.192.1 to 112.6.255.254112.6.255.25516,382
29112.7.0.0/18112.7.0.1 to 112.7.63.254112.7.63.25516,382
30112.7.64.0/18112.7.64.1 to 112.7.127.254112.7.127.25516,382
31112.7.128.0/18112.7.128.1 to 112.7.191.254112.7.191.25516,382
32112.7.192.0/18112.7.192.1 to 112.7.255.254112.7.255.25516,382
33112.8.0.0/18112.8.0.1 to 112.8.63.254112.8.63.25516,382
34112.8.64.0/18112.8.64.1 to 112.8.127.254112.8.127.25516,382
35112.8.128.0/18112.8.128.1 to 112.8.191.254112.8.191.25516,382
36112.8.192.0/18112.8.192.1 to 112.8.255.254112.8.255.25516,382
37112.9.0.0/18112.9.0.1 to 112.9.63.254112.9.63.25516,382
38112.9.64.0/18112.9.64.1 to 112.9.127.254112.9.127.25516,382
39112.9.128.0/18112.9.128.1 to 112.9.191.254112.9.191.25516,382
40112.9.192.0/18112.9.192.1 to 112.9.255.254112.9.255.25516,382
41112.10.0.0/18112.10.0.1 to 112.10.63.254112.10.63.25516,382
42112.10.64.0/18112.10.64.1 to 112.10.127.254112.10.127.25516,382
43112.10.128.0/18112.10.128.1 to 112.10.191.254112.10.191.25516,382
44112.10.192.0/18112.10.192.1 to 112.10.255.254112.10.255.25516,382
45112.11.0.0/18112.11.0.1 to 112.11.63.254112.11.63.25516,382
46112.11.64.0/18112.11.64.1 to 112.11.127.254112.11.127.25516,382
47112.11.128.0/18112.11.128.1 to 112.11.191.254112.11.191.25516,382
48112.11.192.0/18112.11.192.1 to 112.11.255.254112.11.255.25516,382
49112.12.0.0/18112.12.0.1 to 112.12.63.254112.12.63.25516,382
50112.12.64.0/18112.12.64.1 to 112.12.127.254112.12.127.25516,382
51112.12.128.0/18112.12.128.1 to 112.12.191.254112.12.191.25516,382
52112.12.192.0/18112.12.192.1 to 112.12.255.254112.12.255.25516,382
53112.13.0.0/18112.13.0.1 to 112.13.63.254112.13.63.25516,382
54112.13.64.0/18112.13.64.1 to 112.13.127.254112.13.127.25516,382
55112.13.128.0/18112.13.128.1 to 112.13.191.254112.13.191.25516,382
56112.13.192.0/18112.13.192.1 to 112.13.255.254112.13.255.25516,382
57112.14.0.0/18112.14.0.1 to 112.14.63.254112.14.63.25516,382
58112.14.64.0/18112.14.64.1 to 112.14.127.254112.14.127.25516,382
59112.14.128.0/18112.14.128.1 to 112.14.191.254112.14.191.25516,382
60112.14.192.0/18112.14.192.1 to 112.14.255.254112.14.255.25516,382
61112.15.0.0/18112.15.0.1 to 112.15.63.254112.15.63.25516,382
62112.15.64.0/18112.15.64.1 to 112.15.127.254112.15.127.25516,382
63112.15.128.0/18112.15.128.1 to 112.15.191.254112.15.191.25516,382
64112.15.192.0/18112.15.192.1 to 112.15.255.254112.15.255.25516,382
65112.16.0.0/18112.16.0.1 to 112.16.63.254112.16.63.25516,382
66112.16.64.0/18112.16.64.1 to 112.16.127.254112.16.127.25516,382
67112.16.128.0/18112.16.128.1 to 112.16.191.254112.16.191.25516,382
68112.16.192.0/18112.16.192.1 to 112.16.255.254112.16.255.25516,382
69112.17.0.0/18112.17.0.1 to 112.17.63.254112.17.63.25516,382
70112.17.64.0/18112.17.64.1 to 112.17.127.254112.17.127.25516,382
71112.17.128.0/18112.17.128.1 to 112.17.191.254112.17.191.25516,382
72112.17.192.0/18112.17.192.1 to 112.17.255.254112.17.255.25516,382
73112.18.0.0/18112.18.0.1 to 112.18.63.254112.18.63.25516,382
74112.18.64.0/18112.18.64.1 to 112.18.127.254112.18.127.25516,382
75112.18.128.0/18112.18.128.1 to 112.18.191.254112.18.191.25516,382
76112.18.192.0/18112.18.192.1 to 112.18.255.254112.18.255.25516,382
77112.19.0.0/18112.19.0.1 to 112.19.63.254112.19.63.25516,382
78112.19.64.0/18112.19.64.1 to 112.19.127.254112.19.127.25516,382
79112.19.128.0/18112.19.128.1 to 112.19.191.254112.19.191.25516,382
80112.19.192.0/18112.19.192.1 to 112.19.255.254112.19.255.25516,382
81112.20.0.0/18112.20.0.1 to 112.20.63.254112.20.63.25516,382
82112.20.64.0/18112.20.64.1 to 112.20.127.254112.20.127.25516,382
83112.20.128.0/18112.20.128.1 to 112.20.191.254112.20.191.25516,382
84112.20.192.0/18112.20.192.1 to 112.20.255.254112.20.255.25516,382
85112.21.0.0/18112.21.0.1 to 112.21.63.254112.21.63.25516,382
86112.21.64.0/18112.21.64.1 to 112.21.127.254112.21.127.25516,382
87112.21.128.0/18112.21.128.1 to 112.21.191.254112.21.191.25516,382
88112.21.192.0/18112.21.192.1 to 112.21.255.254112.21.255.25516,382
89112.22.0.0/18112.22.0.1 to 112.22.63.254112.22.63.25516,382
90112.22.64.0/18112.22.64.1 to 112.22.127.254112.22.127.25516,382
91112.22.128.0/18112.22.128.1 to 112.22.191.254112.22.191.25516,382
92112.22.192.0/18112.22.192.1 to 112.22.255.254112.22.255.25516,382
93112.23.0.0/18112.23.0.1 to 112.23.63.254112.23.63.25516,382
94112.23.64.0/18112.23.64.1 to 112.23.127.254112.23.127.25516,382
95112.23.128.0/18112.23.128.1 to 112.23.191.254112.23.191.25516,382
96112.23.192.0/18112.23.192.1 to 112.23.255.254112.23.255.25516,382
97112.24.0.0/18112.24.0.1 to 112.24.63.254112.24.63.25516,382
98112.24.64.0/18112.24.64.1 to 112.24.127.254112.24.127.25516,382
99112.24.128.0/18112.24.128.1 to 112.24.191.254112.24.191.25516,382
100112.24.192.0/18112.24.192.1 to 112.24.255.254112.24.255.25516,382
101112.25.0.0/18112.25.0.1 to 112.25.63.254112.25.63.25516,382
102112.25.64.0/18112.25.64.1 to 112.25.127.254112.25.127.25516,382
103112.25.128.0/18112.25.128.1 to 112.25.191.254112.25.191.25516,382
104112.25.192.0/18112.25.192.1 to 112.25.255.254112.25.255.25516,382
105112.26.0.0/18112.26.0.1 to 112.26.63.254112.26.63.25516,382
106112.26.64.0/18112.26.64.1 to 112.26.127.254112.26.127.25516,382
107112.26.128.0/18112.26.128.1 to 112.26.191.254112.26.191.25516,382
108112.26.192.0/18112.26.192.1 to 112.26.255.254112.26.255.25516,382
109112.27.0.0/18112.27.0.1 to 112.27.63.254112.27.63.25516,382
110112.27.64.0/18112.27.64.1 to 112.27.127.254112.27.127.25516,382
111112.27.128.0/18112.27.128.1 to 112.27.191.254112.27.191.25516,382
112112.27.192.0/18112.27.192.1 to 112.27.255.254112.27.255.25516,382
113112.28.0.0/18112.28.0.1 to 112.28.63.254112.28.63.25516,382
114112.28.64.0/18112.28.64.1 to 112.28.127.254112.28.127.25516,382
115112.28.128.0/18112.28.128.1 to 112.28.191.254112.28.191.25516,382
116112.28.192.0/18112.28.192.1 to 112.28.255.254112.28.255.25516,382
117112.29.0.0/18112.29.0.1 to 112.29.63.254112.29.63.25516,382
118112.29.64.0/18112.29.64.1 to 112.29.127.254112.29.127.25516,382
119112.29.128.0/18112.29.128.1 to 112.29.191.254112.29.191.25516,382
120112.29.192.0/18112.29.192.1 to 112.29.255.254112.29.255.25516,382
121112.30.0.0/18112.30.0.1 to 112.30.63.254112.30.63.25516,382
122112.30.64.0/18112.30.64.1 to 112.30.127.254112.30.127.25516,382
123112.30.128.0/18112.30.128.1 to 112.30.191.254112.30.191.25516,382
124112.30.192.0/18112.30.192.1 to 112.30.255.254112.30.255.25516,382
125112.31.0.0/18112.31.0.1 to 112.31.63.254112.31.63.25516,382
126112.31.64.0/18112.31.64.1 to 112.31.127.254112.31.127.25516,382
127112.31.128.0/18112.31.128.1 to 112.31.191.254112.31.191.25516,382
128112.31.192.0/18112.31.192.1 to 112.31.255.254112.31.255.25516,382
129112.32.0.0/18112.32.0.1 to 112.32.63.254112.32.63.25516,382
130112.32.64.0/18112.32.64.1 to 112.32.127.254112.32.127.25516,382
131112.32.128.0/18112.32.128.1 to 112.32.191.254112.32.191.25516,382
132112.32.192.0/18112.32.192.1 to 112.32.255.254112.32.255.25516,382
133112.33.0.0/18112.33.0.1 to 112.33.63.254112.33.63.25516,382
134112.33.64.0/18112.33.64.1 to 112.33.127.254112.33.127.25516,382
135112.33.128.0/18112.33.128.1 to 112.33.191.254112.33.191.25516,382
136112.33.192.0/18112.33.192.1 to 112.33.255.254112.33.255.25516,382
137112.34.0.0/18112.34.0.1 to 112.34.63.254112.34.63.25516,382
138112.34.64.0/18112.34.64.1 to 112.34.127.254112.34.127.25516,382
139112.34.128.0/18112.34.128.1 to 112.34.191.254112.34.191.25516,382
140112.34.192.0/18112.34.192.1 to 112.34.255.254112.34.255.25516,382
141112.35.0.0/18112.35.0.1 to 112.35.63.254112.35.63.25516,382
142112.35.64.0/18112.35.64.1 to 112.35.127.254112.35.127.25516,382
143112.35.128.0/18112.35.128.1 to 112.35.191.254112.35.191.25516,382
144112.35.192.0/18112.35.192.1 to 112.35.255.254112.35.255.25516,382
145112.36.0.0/18112.36.0.1 to 112.36.63.254112.36.63.25516,382
146112.36.64.0/18112.36.64.1 to 112.36.127.254112.36.127.25516,382
147112.36.128.0/18112.36.128.1 to 112.36.191.254112.36.191.25516,382
148112.36.192.0/18112.36.192.1 to 112.36.255.254112.36.255.25516,382
149112.37.0.0/18112.37.0.1 to 112.37.63.254112.37.63.25516,382
150112.37.64.0/18112.37.64.1 to 112.37.127.254112.37.127.25516,382
151112.37.128.0/18112.37.128.1 to 112.37.191.254112.37.191.25516,382
152112.37.192.0/18112.37.192.1 to 112.37.255.254112.37.255.25516,382
153112.38.0.0/18112.38.0.1 to 112.38.63.254112.38.63.25516,382
154112.38.64.0/18112.38.64.1 to 112.38.127.254112.38.127.25516,382
155112.38.128.0/18112.38.128.1 to 112.38.191.254112.38.191.25516,382
156112.38.192.0/18112.38.192.1 to 112.38.255.254112.38.255.25516,382
157112.39.0.0/18112.39.0.1 to 112.39.63.254112.39.63.25516,382
158112.39.64.0/18112.39.64.1 to 112.39.127.254112.39.127.25516,382
159112.39.128.0/18112.39.128.1 to 112.39.191.254112.39.191.25516,382
160112.39.192.0/18112.39.192.1 to 112.39.255.254112.39.255.25516,382
161112.40.0.0/18112.40.0.1 to 112.40.63.254112.40.63.25516,382
162112.40.64.0/18112.40.64.1 to 112.40.127.254112.40.127.25516,382
163112.40.128.0/18112.40.128.1 to 112.40.191.254112.40.191.25516,382
164112.40.192.0/18112.40.192.1 to 112.40.255.254112.40.255.25516,382
165112.41.0.0/18112.41.0.1 to 112.41.63.254112.41.63.25516,382
166112.41.64.0/18112.41.64.1 to 112.41.127.254112.41.127.25516,382
167112.41.128.0/18112.41.128.1 to 112.41.191.254112.41.191.25516,382
168112.41.192.0/18112.41.192.1 to 112.41.255.254112.41.255.25516,382
169112.42.0.0/18112.42.0.1 to 112.42.63.254112.42.63.25516,382
170112.42.64.0/18112.42.64.1 to 112.42.127.254112.42.127.25516,382
171112.42.128.0/18112.42.128.1 to 112.42.191.254112.42.191.25516,382
172112.42.192.0/18112.42.192.1 to 112.42.255.254112.42.255.25516,382
173112.43.0.0/18112.43.0.1 to 112.43.63.254112.43.63.25516,382
174112.43.64.0/18112.43.64.1 to 112.43.127.254112.43.127.25516,382
175112.43.128.0/18112.43.128.1 to 112.43.191.254112.43.191.25516,382
176112.43.192.0/18112.43.192.1 to 112.43.255.254112.43.255.25516,382
177112.44.0.0/18112.44.0.1 to 112.44.63.254112.44.63.25516,382
178112.44.64.0/18112.44.64.1 to 112.44.127.254112.44.127.25516,382
179112.44.128.0/18112.44.128.1 to 112.44.191.254112.44.191.25516,382
180112.44.192.0/18112.44.192.1 to 112.44.255.254112.44.255.25516,382
181112.45.0.0/18112.45.0.1 to 112.45.63.254112.45.63.25516,382
182112.45.64.0/18112.45.64.1 to 112.45.127.254112.45.127.25516,382
183112.45.128.0/18112.45.128.1 to 112.45.191.254112.45.191.25516,382
184112.45.192.0/18112.45.192.1 to 112.45.255.254112.45.255.25516,382
185112.46.0.0/18112.46.0.1 to 112.46.63.254112.46.63.25516,382
186112.46.64.0/18112.46.64.1 to 112.46.127.254112.46.127.25516,382
187112.46.128.0/18112.46.128.1 to 112.46.191.254112.46.191.25516,382
188112.46.192.0/18112.46.192.1 to 112.46.255.254112.46.255.25516,382
189112.47.0.0/18112.47.0.1 to 112.47.63.254112.47.63.25516,382
190112.47.64.0/18112.47.64.1 to 112.47.127.254112.47.127.25516,382
191112.47.128.0/18112.47.128.1 to 112.47.191.254112.47.191.25516,382
192112.47.192.0/18112.47.192.1 to 112.47.255.254112.47.255.25516,382
193112.48.0.0/18112.48.0.1 to 112.48.63.254112.48.63.25516,382
194112.48.64.0/18112.48.64.1 to 112.48.127.254112.48.127.25516,382
195112.48.128.0/18112.48.128.1 to 112.48.191.254112.48.191.25516,382
196112.48.192.0/18112.48.192.1 to 112.48.255.254112.48.255.25516,382
197112.49.0.0/18112.49.0.1 to 112.49.63.254112.49.63.25516,382
198112.49.64.0/18112.49.64.1 to 112.49.127.254112.49.127.25516,382
199112.49.128.0/18112.49.128.1 to 112.49.191.254112.49.191.25516,382
200112.49.192.0/18112.49.192.1 to 112.49.255.254112.49.255.25516,382
201112.50.0.0/18112.50.0.1 to 112.50.63.254112.50.63.25516,382
202112.50.64.0/18112.50.64.1 to 112.50.127.254112.50.127.25516,382
203112.50.128.0/18112.50.128.1 to 112.50.191.254112.50.191.25516,382
204112.50.192.0/18112.50.192.1 to 112.50.255.254112.50.255.25516,382
205112.51.0.0/18112.51.0.1 to 112.51.63.254112.51.63.25516,382
206112.51.64.0/18112.51.64.1 to 112.51.127.254112.51.127.25516,382
207112.51.128.0/18112.51.128.1 to 112.51.191.254112.51.191.25516,382
208112.51.192.0/18112.51.192.1 to 112.51.255.254112.51.255.25516,382
209112.52.0.0/18112.52.0.1 to 112.52.63.254112.52.63.25516,382
210112.52.64.0/18112.52.64.1 to 112.52.127.254112.52.127.25516,382
211112.52.128.0/18112.52.128.1 to 112.52.191.254112.52.191.25516,382
212112.52.192.0/18112.52.192.1 to 112.52.255.254112.52.255.25516,382
213112.53.0.0/18112.53.0.1 to 112.53.63.254112.53.63.25516,382
214112.53.64.0/18112.53.64.1 to 112.53.127.254112.53.127.25516,382
215112.53.128.0/18112.53.128.1 to 112.53.191.254112.53.191.25516,382
216112.53.192.0/18112.53.192.1 to 112.53.255.254112.53.255.25516,382
217112.54.0.0/18112.54.0.1 to 112.54.63.254112.54.63.25516,382
218112.54.64.0/18112.54.64.1 to 112.54.127.254112.54.127.25516,382
219112.54.128.0/18112.54.128.1 to 112.54.191.254112.54.191.25516,382
220112.54.192.0/18112.54.192.1 to 112.54.255.254112.54.255.25516,382
221112.55.0.0/18112.55.0.1 to 112.55.63.254112.55.63.25516,382
222112.55.64.0/18112.55.64.1 to 112.55.127.254112.55.127.25516,382
223112.55.128.0/18112.55.128.1 to 112.55.191.254112.55.191.25516,382
224112.55.192.0/18112.55.192.1 to 112.55.255.254112.55.255.25516,382
225112.56.0.0/18112.56.0.1 to 112.56.63.254112.56.63.25516,382
226112.56.64.0/18112.56.64.1 to 112.56.127.254112.56.127.25516,382
227112.56.128.0/18112.56.128.1 to 112.56.191.254112.56.191.25516,382
228112.56.192.0/18112.56.192.1 to 112.56.255.254112.56.255.25516,382
229112.57.0.0/18112.57.0.1 to 112.57.63.254112.57.63.25516,382
230112.57.64.0/18112.57.64.1 to 112.57.127.254112.57.127.25516,382
231112.57.128.0/18112.57.128.1 to 112.57.191.254112.57.191.25516,382
232112.57.192.0/18112.57.192.1 to 112.57.255.254112.57.255.25516,382
233112.58.0.0/18112.58.0.1 to 112.58.63.254112.58.63.25516,382
234112.58.64.0/18112.58.64.1 to 112.58.127.254112.58.127.25516,382
235112.58.128.0/18112.58.128.1 to 112.58.191.254112.58.191.25516,382
236112.58.192.0/18112.58.192.1 to 112.58.255.254112.58.255.25516,382
237112.59.0.0/18112.59.0.1 to 112.59.63.254112.59.63.25516,382
238112.59.64.0/18112.59.64.1 to 112.59.127.254112.59.127.25516,382
239112.59.128.0/18112.59.128.1 to 112.59.191.254112.59.191.25516,382
240112.59.192.0/18112.59.192.1 to 112.59.255.254112.59.255.25516,382
241112.60.0.0/18112.60.0.1 to 112.60.63.254112.60.63.25516,382
242112.60.64.0/18112.60.64.1 to 112.60.127.254112.60.127.25516,382
243112.60.128.0/18112.60.128.1 to 112.60.191.254112.60.191.25516,382
244112.60.192.0/18112.60.192.1 to 112.60.255.254112.60.255.25516,382
245112.61.0.0/18112.61.0.1 to 112.61.63.254112.61.63.25516,382
246112.61.64.0/18112.61.64.1 to 112.61.127.254112.61.127.25516,382
247112.61.128.0/18112.61.128.1 to 112.61.191.254112.61.191.25516,382
248112.61.192.0/18112.61.192.1 to 112.61.255.254112.61.255.25516,382
249112.62.0.0/18112.62.0.1 to 112.62.63.254112.62.63.25516,382
250112.62.64.0/18112.62.64.1 to 112.62.127.254112.62.127.25516,382
251112.62.128.0/18112.62.128.1 to 112.62.191.254112.62.191.25516,382
252112.62.192.0/18112.62.192.1 to 112.62.255.254112.62.255.25516,382
253112.63.0.0/18112.63.0.1 to 112.63.63.254112.63.63.25516,382
254112.63.64.0/18112.63.64.1 to 112.63.127.254112.63.127.25516,382
255112.63.128.0/18112.63.128.1 to 112.63.191.254112.63.191.25516,382
256112.63.192.0/18112.63.192.1 to 112.63.255.254112.63.255.25516,382

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.