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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/17
/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 512 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1112.0.0.0/17112.0.0.1 to 112.0.127.254112.0.127.25532,766
2112.0.128.0/17112.0.128.1 to 112.0.255.254112.0.255.25532,766
3112.1.0.0/17112.1.0.1 to 112.1.127.254112.1.127.25532,766
4112.1.128.0/17112.1.128.1 to 112.1.255.254112.1.255.25532,766
5112.2.0.0/17112.2.0.1 to 112.2.127.254112.2.127.25532,766
6112.2.128.0/17112.2.128.1 to 112.2.255.254112.2.255.25532,766
7112.3.0.0/17112.3.0.1 to 112.3.127.254112.3.127.25532,766
8112.3.128.0/17112.3.128.1 to 112.3.255.254112.3.255.25532,766
9112.4.0.0/17112.4.0.1 to 112.4.127.254112.4.127.25532,766
10112.4.128.0/17112.4.128.1 to 112.4.255.254112.4.255.25532,766
11112.5.0.0/17112.5.0.1 to 112.5.127.254112.5.127.25532,766
12112.5.128.0/17112.5.128.1 to 112.5.255.254112.5.255.25532,766
13112.6.0.0/17112.6.0.1 to 112.6.127.254112.6.127.25532,766
14112.6.128.0/17112.6.128.1 to 112.6.255.254112.6.255.25532,766
15112.7.0.0/17112.7.0.1 to 112.7.127.254112.7.127.25532,766
16112.7.128.0/17112.7.128.1 to 112.7.255.254112.7.255.25532,766
17112.8.0.0/17112.8.0.1 to 112.8.127.254112.8.127.25532,766
18112.8.128.0/17112.8.128.1 to 112.8.255.254112.8.255.25532,766
19112.9.0.0/17112.9.0.1 to 112.9.127.254112.9.127.25532,766
20112.9.128.0/17112.9.128.1 to 112.9.255.254112.9.255.25532,766
21112.10.0.0/17112.10.0.1 to 112.10.127.254112.10.127.25532,766
22112.10.128.0/17112.10.128.1 to 112.10.255.254112.10.255.25532,766
23112.11.0.0/17112.11.0.1 to 112.11.127.254112.11.127.25532,766
24112.11.128.0/17112.11.128.1 to 112.11.255.254112.11.255.25532,766
25112.12.0.0/17112.12.0.1 to 112.12.127.254112.12.127.25532,766
26112.12.128.0/17112.12.128.1 to 112.12.255.254112.12.255.25532,766
27112.13.0.0/17112.13.0.1 to 112.13.127.254112.13.127.25532,766
28112.13.128.0/17112.13.128.1 to 112.13.255.254112.13.255.25532,766
29112.14.0.0/17112.14.0.1 to 112.14.127.254112.14.127.25532,766
30112.14.128.0/17112.14.128.1 to 112.14.255.254112.14.255.25532,766
31112.15.0.0/17112.15.0.1 to 112.15.127.254112.15.127.25532,766
32112.15.128.0/17112.15.128.1 to 112.15.255.254112.15.255.25532,766
33112.16.0.0/17112.16.0.1 to 112.16.127.254112.16.127.25532,766
34112.16.128.0/17112.16.128.1 to 112.16.255.254112.16.255.25532,766
35112.17.0.0/17112.17.0.1 to 112.17.127.254112.17.127.25532,766
36112.17.128.0/17112.17.128.1 to 112.17.255.254112.17.255.25532,766
37112.18.0.0/17112.18.0.1 to 112.18.127.254112.18.127.25532,766
38112.18.128.0/17112.18.128.1 to 112.18.255.254112.18.255.25532,766
39112.19.0.0/17112.19.0.1 to 112.19.127.254112.19.127.25532,766
40112.19.128.0/17112.19.128.1 to 112.19.255.254112.19.255.25532,766
41112.20.0.0/17112.20.0.1 to 112.20.127.254112.20.127.25532,766
42112.20.128.0/17112.20.128.1 to 112.20.255.254112.20.255.25532,766
43112.21.0.0/17112.21.0.1 to 112.21.127.254112.21.127.25532,766
44112.21.128.0/17112.21.128.1 to 112.21.255.254112.21.255.25532,766
45112.22.0.0/17112.22.0.1 to 112.22.127.254112.22.127.25532,766
46112.22.128.0/17112.22.128.1 to 112.22.255.254112.22.255.25532,766
47112.23.0.0/17112.23.0.1 to 112.23.127.254112.23.127.25532,766
48112.23.128.0/17112.23.128.1 to 112.23.255.254112.23.255.25532,766
49112.24.0.0/17112.24.0.1 to 112.24.127.254112.24.127.25532,766
50112.24.128.0/17112.24.128.1 to 112.24.255.254112.24.255.25532,766
51112.25.0.0/17112.25.0.1 to 112.25.127.254112.25.127.25532,766
52112.25.128.0/17112.25.128.1 to 112.25.255.254112.25.255.25532,766
53112.26.0.0/17112.26.0.1 to 112.26.127.254112.26.127.25532,766
54112.26.128.0/17112.26.128.1 to 112.26.255.254112.26.255.25532,766
55112.27.0.0/17112.27.0.1 to 112.27.127.254112.27.127.25532,766
56112.27.128.0/17112.27.128.1 to 112.27.255.254112.27.255.25532,766
57112.28.0.0/17112.28.0.1 to 112.28.127.254112.28.127.25532,766
58112.28.128.0/17112.28.128.1 to 112.28.255.254112.28.255.25532,766
59112.29.0.0/17112.29.0.1 to 112.29.127.254112.29.127.25532,766
60112.29.128.0/17112.29.128.1 to 112.29.255.254112.29.255.25532,766
61112.30.0.0/17112.30.0.1 to 112.30.127.254112.30.127.25532,766
62112.30.128.0/17112.30.128.1 to 112.30.255.254112.30.255.25532,766
63112.31.0.0/17112.31.0.1 to 112.31.127.254112.31.127.25532,766
64112.31.128.0/17112.31.128.1 to 112.31.255.254112.31.255.25532,766
65112.32.0.0/17112.32.0.1 to 112.32.127.254112.32.127.25532,766
66112.32.128.0/17112.32.128.1 to 112.32.255.254112.32.255.25532,766
67112.33.0.0/17112.33.0.1 to 112.33.127.254112.33.127.25532,766
68112.33.128.0/17112.33.128.1 to 112.33.255.254112.33.255.25532,766
69112.34.0.0/17112.34.0.1 to 112.34.127.254112.34.127.25532,766
70112.34.128.0/17112.34.128.1 to 112.34.255.254112.34.255.25532,766
71112.35.0.0/17112.35.0.1 to 112.35.127.254112.35.127.25532,766
72112.35.128.0/17112.35.128.1 to 112.35.255.254112.35.255.25532,766
73112.36.0.0/17112.36.0.1 to 112.36.127.254112.36.127.25532,766
74112.36.128.0/17112.36.128.1 to 112.36.255.254112.36.255.25532,766
75112.37.0.0/17112.37.0.1 to 112.37.127.254112.37.127.25532,766
76112.37.128.0/17112.37.128.1 to 112.37.255.254112.37.255.25532,766
77112.38.0.0/17112.38.0.1 to 112.38.127.254112.38.127.25532,766
78112.38.128.0/17112.38.128.1 to 112.38.255.254112.38.255.25532,766
79112.39.0.0/17112.39.0.1 to 112.39.127.254112.39.127.25532,766
80112.39.128.0/17112.39.128.1 to 112.39.255.254112.39.255.25532,766
81112.40.0.0/17112.40.0.1 to 112.40.127.254112.40.127.25532,766
82112.40.128.0/17112.40.128.1 to 112.40.255.254112.40.255.25532,766
83112.41.0.0/17112.41.0.1 to 112.41.127.254112.41.127.25532,766
84112.41.128.0/17112.41.128.1 to 112.41.255.254112.41.255.25532,766
85112.42.0.0/17112.42.0.1 to 112.42.127.254112.42.127.25532,766
86112.42.128.0/17112.42.128.1 to 112.42.255.254112.42.255.25532,766
87112.43.0.0/17112.43.0.1 to 112.43.127.254112.43.127.25532,766
88112.43.128.0/17112.43.128.1 to 112.43.255.254112.43.255.25532,766
89112.44.0.0/17112.44.0.1 to 112.44.127.254112.44.127.25532,766
90112.44.128.0/17112.44.128.1 to 112.44.255.254112.44.255.25532,766
91112.45.0.0/17112.45.0.1 to 112.45.127.254112.45.127.25532,766
92112.45.128.0/17112.45.128.1 to 112.45.255.254112.45.255.25532,766
93112.46.0.0/17112.46.0.1 to 112.46.127.254112.46.127.25532,766
94112.46.128.0/17112.46.128.1 to 112.46.255.254112.46.255.25532,766
95112.47.0.0/17112.47.0.1 to 112.47.127.254112.47.127.25532,766
96112.47.128.0/17112.47.128.1 to 112.47.255.254112.47.255.25532,766
97112.48.0.0/17112.48.0.1 to 112.48.127.254112.48.127.25532,766
98112.48.128.0/17112.48.128.1 to 112.48.255.254112.48.255.25532,766
99112.49.0.0/17112.49.0.1 to 112.49.127.254112.49.127.25532,766
100112.49.128.0/17112.49.128.1 to 112.49.255.254112.49.255.25532,766
101112.50.0.0/17112.50.0.1 to 112.50.127.254112.50.127.25532,766
102112.50.128.0/17112.50.128.1 to 112.50.255.254112.50.255.25532,766
103112.51.0.0/17112.51.0.1 to 112.51.127.254112.51.127.25532,766
104112.51.128.0/17112.51.128.1 to 112.51.255.254112.51.255.25532,766
105112.52.0.0/17112.52.0.1 to 112.52.127.254112.52.127.25532,766
106112.52.128.0/17112.52.128.1 to 112.52.255.254112.52.255.25532,766
107112.53.0.0/17112.53.0.1 to 112.53.127.254112.53.127.25532,766
108112.53.128.0/17112.53.128.1 to 112.53.255.254112.53.255.25532,766
109112.54.0.0/17112.54.0.1 to 112.54.127.254112.54.127.25532,766
110112.54.128.0/17112.54.128.1 to 112.54.255.254112.54.255.25532,766
111112.55.0.0/17112.55.0.1 to 112.55.127.254112.55.127.25532,766
112112.55.128.0/17112.55.128.1 to 112.55.255.254112.55.255.25532,766
113112.56.0.0/17112.56.0.1 to 112.56.127.254112.56.127.25532,766
114112.56.128.0/17112.56.128.1 to 112.56.255.254112.56.255.25532,766
115112.57.0.0/17112.57.0.1 to 112.57.127.254112.57.127.25532,766
116112.57.128.0/17112.57.128.1 to 112.57.255.254112.57.255.25532,766
117112.58.0.0/17112.58.0.1 to 112.58.127.254112.58.127.25532,766
118112.58.128.0/17112.58.128.1 to 112.58.255.254112.58.255.25532,766
119112.59.0.0/17112.59.0.1 to 112.59.127.254112.59.127.25532,766
120112.59.128.0/17112.59.128.1 to 112.59.255.254112.59.255.25532,766
121112.60.0.0/17112.60.0.1 to 112.60.127.254112.60.127.25532,766
122112.60.128.0/17112.60.128.1 to 112.60.255.254112.60.255.25532,766
123112.61.0.0/17112.61.0.1 to 112.61.127.254112.61.127.25532,766
124112.61.128.0/17112.61.128.1 to 112.61.255.254112.61.255.25532,766
125112.62.0.0/17112.62.0.1 to 112.62.127.254112.62.127.25532,766
126112.62.128.0/17112.62.128.1 to 112.62.255.254112.62.255.25532,766
127112.63.0.0/17112.63.0.1 to 112.63.127.254112.63.127.25532,766
128112.63.128.0/17112.63.128.1 to 112.63.255.254112.63.255.25532,766
129112.64.0.0/17112.64.0.1 to 112.64.127.254112.64.127.25532,766
130112.64.128.0/17112.64.128.1 to 112.64.255.254112.64.255.25532,766
131112.65.0.0/17112.65.0.1 to 112.65.127.254112.65.127.25532,766
132112.65.128.0/17112.65.128.1 to 112.65.255.254112.65.255.25532,766
133112.66.0.0/17112.66.0.1 to 112.66.127.254112.66.127.25532,766
134112.66.128.0/17112.66.128.1 to 112.66.255.254112.66.255.25532,766
135112.67.0.0/17112.67.0.1 to 112.67.127.254112.67.127.25532,766
136112.67.128.0/17112.67.128.1 to 112.67.255.254112.67.255.25532,766
137112.68.0.0/17112.68.0.1 to 112.68.127.254112.68.127.25532,766
138112.68.128.0/17112.68.128.1 to 112.68.255.254112.68.255.25532,766
139112.69.0.0/17112.69.0.1 to 112.69.127.254112.69.127.25532,766
140112.69.128.0/17112.69.128.1 to 112.69.255.254112.69.255.25532,766
141112.70.0.0/17112.70.0.1 to 112.70.127.254112.70.127.25532,766
142112.70.128.0/17112.70.128.1 to 112.70.255.254112.70.255.25532,766
143112.71.0.0/17112.71.0.1 to 112.71.127.254112.71.127.25532,766
144112.71.128.0/17112.71.128.1 to 112.71.255.254112.71.255.25532,766
145112.72.0.0/17112.72.0.1 to 112.72.127.254112.72.127.25532,766
146112.72.128.0/17112.72.128.1 to 112.72.255.254112.72.255.25532,766
147112.73.0.0/17112.73.0.1 to 112.73.127.254112.73.127.25532,766
148112.73.128.0/17112.73.128.1 to 112.73.255.254112.73.255.25532,766
149112.74.0.0/17112.74.0.1 to 112.74.127.254112.74.127.25532,766
150112.74.128.0/17112.74.128.1 to 112.74.255.254112.74.255.25532,766
151112.75.0.0/17112.75.0.1 to 112.75.127.254112.75.127.25532,766
152112.75.128.0/17112.75.128.1 to 112.75.255.254112.75.255.25532,766
153112.76.0.0/17112.76.0.1 to 112.76.127.254112.76.127.25532,766
154112.76.128.0/17112.76.128.1 to 112.76.255.254112.76.255.25532,766
155112.77.0.0/17112.77.0.1 to 112.77.127.254112.77.127.25532,766
156112.77.128.0/17112.77.128.1 to 112.77.255.254112.77.255.25532,766
157112.78.0.0/17112.78.0.1 to 112.78.127.254112.78.127.25532,766
158112.78.128.0/17112.78.128.1 to 112.78.255.254112.78.255.25532,766
159112.79.0.0/17112.79.0.1 to 112.79.127.254112.79.127.25532,766
160112.79.128.0/17112.79.128.1 to 112.79.255.254112.79.255.25532,766
161112.80.0.0/17112.80.0.1 to 112.80.127.254112.80.127.25532,766
162112.80.128.0/17112.80.128.1 to 112.80.255.254112.80.255.25532,766
163112.81.0.0/17112.81.0.1 to 112.81.127.254112.81.127.25532,766
164112.81.128.0/17112.81.128.1 to 112.81.255.254112.81.255.25532,766
165112.82.0.0/17112.82.0.1 to 112.82.127.254112.82.127.25532,766
166112.82.128.0/17112.82.128.1 to 112.82.255.254112.82.255.25532,766
167112.83.0.0/17112.83.0.1 to 112.83.127.254112.83.127.25532,766
168112.83.128.0/17112.83.128.1 to 112.83.255.254112.83.255.25532,766
169112.84.0.0/17112.84.0.1 to 112.84.127.254112.84.127.25532,766
170112.84.128.0/17112.84.128.1 to 112.84.255.254112.84.255.25532,766
171112.85.0.0/17112.85.0.1 to 112.85.127.254112.85.127.25532,766
172112.85.128.0/17112.85.128.1 to 112.85.255.254112.85.255.25532,766
173112.86.0.0/17112.86.0.1 to 112.86.127.254112.86.127.25532,766
174112.86.128.0/17112.86.128.1 to 112.86.255.254112.86.255.25532,766
175112.87.0.0/17112.87.0.1 to 112.87.127.254112.87.127.25532,766
176112.87.128.0/17112.87.128.1 to 112.87.255.254112.87.255.25532,766
177112.88.0.0/17112.88.0.1 to 112.88.127.254112.88.127.25532,766
178112.88.128.0/17112.88.128.1 to 112.88.255.254112.88.255.25532,766
179112.89.0.0/17112.89.0.1 to 112.89.127.254112.89.127.25532,766
180112.89.128.0/17112.89.128.1 to 112.89.255.254112.89.255.25532,766
181112.90.0.0/17112.90.0.1 to 112.90.127.254112.90.127.25532,766
182112.90.128.0/17112.90.128.1 to 112.90.255.254112.90.255.25532,766
183112.91.0.0/17112.91.0.1 to 112.91.127.254112.91.127.25532,766
184112.91.128.0/17112.91.128.1 to 112.91.255.254112.91.255.25532,766
185112.92.0.0/17112.92.0.1 to 112.92.127.254112.92.127.25532,766
186112.92.128.0/17112.92.128.1 to 112.92.255.254112.92.255.25532,766
187112.93.0.0/17112.93.0.1 to 112.93.127.254112.93.127.25532,766
188112.93.128.0/17112.93.128.1 to 112.93.255.254112.93.255.25532,766
189112.94.0.0/17112.94.0.1 to 112.94.127.254112.94.127.25532,766
190112.94.128.0/17112.94.128.1 to 112.94.255.254112.94.255.25532,766
191112.95.0.0/17112.95.0.1 to 112.95.127.254112.95.127.25532,766
192112.95.128.0/17112.95.128.1 to 112.95.255.254112.95.255.25532,766
193112.96.0.0/17112.96.0.1 to 112.96.127.254112.96.127.25532,766
194112.96.128.0/17112.96.128.1 to 112.96.255.254112.96.255.25532,766
195112.97.0.0/17112.97.0.1 to 112.97.127.254112.97.127.25532,766
196112.97.128.0/17112.97.128.1 to 112.97.255.254112.97.255.25532,766
197112.98.0.0/17112.98.0.1 to 112.98.127.254112.98.127.25532,766
198112.98.128.0/17112.98.128.1 to 112.98.255.254112.98.255.25532,766
199112.99.0.0/17112.99.0.1 to 112.99.127.254112.99.127.25532,766
200112.99.128.0/17112.99.128.1 to 112.99.255.254112.99.255.25532,766
201112.100.0.0/17112.100.0.1 to 112.100.127.254112.100.127.25532,766
202112.100.128.0/17112.100.128.1 to 112.100.255.254112.100.255.25532,766
203112.101.0.0/17112.101.0.1 to 112.101.127.254112.101.127.25532,766
204112.101.128.0/17112.101.128.1 to 112.101.255.254112.101.255.25532,766
205112.102.0.0/17112.102.0.1 to 112.102.127.254112.102.127.25532,766
206112.102.128.0/17112.102.128.1 to 112.102.255.254112.102.255.25532,766
207112.103.0.0/17112.103.0.1 to 112.103.127.254112.103.127.25532,766
208112.103.128.0/17112.103.128.1 to 112.103.255.254112.103.255.25532,766
209112.104.0.0/17112.104.0.1 to 112.104.127.254112.104.127.25532,766
210112.104.128.0/17112.104.128.1 to 112.104.255.254112.104.255.25532,766
211112.105.0.0/17112.105.0.1 to 112.105.127.254112.105.127.25532,766
212112.105.128.0/17112.105.128.1 to 112.105.255.254112.105.255.25532,766
213112.106.0.0/17112.106.0.1 to 112.106.127.254112.106.127.25532,766
214112.106.128.0/17112.106.128.1 to 112.106.255.254112.106.255.25532,766
215112.107.0.0/17112.107.0.1 to 112.107.127.254112.107.127.25532,766
216112.107.128.0/17112.107.128.1 to 112.107.255.254112.107.255.25532,766
217112.108.0.0/17112.108.0.1 to 112.108.127.254112.108.127.25532,766
218112.108.128.0/17112.108.128.1 to 112.108.255.254112.108.255.25532,766
219112.109.0.0/17112.109.0.1 to 112.109.127.254112.109.127.25532,766
220112.109.128.0/17112.109.128.1 to 112.109.255.254112.109.255.25532,766
221112.110.0.0/17112.110.0.1 to 112.110.127.254112.110.127.25532,766
222112.110.128.0/17112.110.128.1 to 112.110.255.254112.110.255.25532,766
223112.111.0.0/17112.111.0.1 to 112.111.127.254112.111.127.25532,766
224112.111.128.0/17112.111.128.1 to 112.111.255.254112.111.255.25532,766
225112.112.0.0/17112.112.0.1 to 112.112.127.254112.112.127.25532,766
226112.112.128.0/17112.112.128.1 to 112.112.255.254112.112.255.25532,766
227112.113.0.0/17112.113.0.1 to 112.113.127.254112.113.127.25532,766
228112.113.128.0/17112.113.128.1 to 112.113.255.254112.113.255.25532,766
229112.114.0.0/17112.114.0.1 to 112.114.127.254112.114.127.25532,766
230112.114.128.0/17112.114.128.1 to 112.114.255.254112.114.255.25532,766
231112.115.0.0/17112.115.0.1 to 112.115.127.254112.115.127.25532,766
232112.115.128.0/17112.115.128.1 to 112.115.255.254112.115.255.25532,766
233112.116.0.0/17112.116.0.1 to 112.116.127.254112.116.127.25532,766
234112.116.128.0/17112.116.128.1 to 112.116.255.254112.116.255.25532,766
235112.117.0.0/17112.117.0.1 to 112.117.127.254112.117.127.25532,766
236112.117.128.0/17112.117.128.1 to 112.117.255.254112.117.255.25532,766
237112.118.0.0/17112.118.0.1 to 112.118.127.254112.118.127.25532,766
238112.118.128.0/17112.118.128.1 to 112.118.255.254112.118.255.25532,766
239112.119.0.0/17112.119.0.1 to 112.119.127.254112.119.127.25532,766
240112.119.128.0/17112.119.128.1 to 112.119.255.254112.119.255.25532,766
241112.120.0.0/17112.120.0.1 to 112.120.127.254112.120.127.25532,766
242112.120.128.0/17112.120.128.1 to 112.120.255.254112.120.255.25532,766
243112.121.0.0/17112.121.0.1 to 112.121.127.254112.121.127.25532,766
244112.121.128.0/17112.121.128.1 to 112.121.255.254112.121.255.25532,766
245112.122.0.0/17112.122.0.1 to 112.122.127.254112.122.127.25532,766
246112.122.128.0/17112.122.128.1 to 112.122.255.254112.122.255.25532,766
247112.123.0.0/17112.123.0.1 to 112.123.127.254112.123.127.25532,766
248112.123.128.0/17112.123.128.1 to 112.123.255.254112.123.255.25532,766
249112.124.0.0/17112.124.0.1 to 112.124.127.254112.124.127.25532,766
250112.124.128.0/17112.124.128.1 to 112.124.255.254112.124.255.25532,766
251112.125.0.0/17112.125.0.1 to 112.125.127.254112.125.127.25532,766
252112.125.128.0/17112.125.128.1 to 112.125.255.254112.125.255.25532,766
253112.126.0.0/17112.126.0.1 to 112.126.127.254112.126.127.25532,766
254112.126.128.0/17112.126.128.1 to 112.126.255.254112.126.255.25532,766
255112.127.0.0/17112.127.0.1 to 112.127.127.254112.127.127.25532,766
256112.127.128.0/17112.127.128.1 to 112.127.255.254112.127.255.25532,766

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.