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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.

Network112.136.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
112.136.0.0
Broadcast address
112.136.255.255
First usable
112.136.0.1
Last usable
112.136.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 70880000 · Integer 1887961088 to 1888026623
Reverse DNS zone
136.112.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110000.10001000..00000000.00000000112.136.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01110000.10001000..00000000.00000000112.136.0.0
Broadcast01110000.10001000..11111111.11111111112.136.255.255
Split into smaller subnets/26
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

112.136.0.0/16 makes 1,024 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1112.136.0.0/26112.136.0.1 to 112.136.0.62112.136.0.6362
2112.136.0.64/26112.136.0.65 to 112.136.0.126112.136.0.12762
3112.136.0.128/26112.136.0.129 to 112.136.0.190112.136.0.19162
4112.136.0.192/26112.136.0.193 to 112.136.0.254112.136.0.25562
5112.136.1.0/26112.136.1.1 to 112.136.1.62112.136.1.6362
6112.136.1.64/26112.136.1.65 to 112.136.1.126112.136.1.12762
7112.136.1.128/26112.136.1.129 to 112.136.1.190112.136.1.19162
8112.136.1.192/26112.136.1.193 to 112.136.1.254112.136.1.25562
9112.136.2.0/26112.136.2.1 to 112.136.2.62112.136.2.6362
10112.136.2.64/26112.136.2.65 to 112.136.2.126112.136.2.12762
11112.136.2.128/26112.136.2.129 to 112.136.2.190112.136.2.19162
12112.136.2.192/26112.136.2.193 to 112.136.2.254112.136.2.25562
13112.136.3.0/26112.136.3.1 to 112.136.3.62112.136.3.6362
14112.136.3.64/26112.136.3.65 to 112.136.3.126112.136.3.12762
15112.136.3.128/26112.136.3.129 to 112.136.3.190112.136.3.19162
16112.136.3.192/26112.136.3.193 to 112.136.3.254112.136.3.25562
17112.136.4.0/26112.136.4.1 to 112.136.4.62112.136.4.6362
18112.136.4.64/26112.136.4.65 to 112.136.4.126112.136.4.12762
19112.136.4.128/26112.136.4.129 to 112.136.4.190112.136.4.19162
20112.136.4.192/26112.136.4.193 to 112.136.4.254112.136.4.25562
21112.136.5.0/26112.136.5.1 to 112.136.5.62112.136.5.6362
22112.136.5.64/26112.136.5.65 to 112.136.5.126112.136.5.12762
23112.136.5.128/26112.136.5.129 to 112.136.5.190112.136.5.19162
24112.136.5.192/26112.136.5.193 to 112.136.5.254112.136.5.25562
25112.136.6.0/26112.136.6.1 to 112.136.6.62112.136.6.6362
26112.136.6.64/26112.136.6.65 to 112.136.6.126112.136.6.12762
27112.136.6.128/26112.136.6.129 to 112.136.6.190112.136.6.19162
28112.136.6.192/26112.136.6.193 to 112.136.6.254112.136.6.25562
29112.136.7.0/26112.136.7.1 to 112.136.7.62112.136.7.6362
30112.136.7.64/26112.136.7.65 to 112.136.7.126112.136.7.12762
31112.136.7.128/26112.136.7.129 to 112.136.7.190112.136.7.19162
32112.136.7.192/26112.136.7.193 to 112.136.7.254112.136.7.25562
33112.136.8.0/26112.136.8.1 to 112.136.8.62112.136.8.6362
34112.136.8.64/26112.136.8.65 to 112.136.8.126112.136.8.12762
35112.136.8.128/26112.136.8.129 to 112.136.8.190112.136.8.19162
36112.136.8.192/26112.136.8.193 to 112.136.8.254112.136.8.25562
37112.136.9.0/26112.136.9.1 to 112.136.9.62112.136.9.6362
38112.136.9.64/26112.136.9.65 to 112.136.9.126112.136.9.12762
39112.136.9.128/26112.136.9.129 to 112.136.9.190112.136.9.19162
40112.136.9.192/26112.136.9.193 to 112.136.9.254112.136.9.25562
41112.136.10.0/26112.136.10.1 to 112.136.10.62112.136.10.6362
42112.136.10.64/26112.136.10.65 to 112.136.10.126112.136.10.12762
43112.136.10.128/26112.136.10.129 to 112.136.10.190112.136.10.19162
44112.136.10.192/26112.136.10.193 to 112.136.10.254112.136.10.25562
45112.136.11.0/26112.136.11.1 to 112.136.11.62112.136.11.6362
46112.136.11.64/26112.136.11.65 to 112.136.11.126112.136.11.12762
47112.136.11.128/26112.136.11.129 to 112.136.11.190112.136.11.19162
48112.136.11.192/26112.136.11.193 to 112.136.11.254112.136.11.25562
49112.136.12.0/26112.136.12.1 to 112.136.12.62112.136.12.6362
50112.136.12.64/26112.136.12.65 to 112.136.12.126112.136.12.12762
51112.136.12.128/26112.136.12.129 to 112.136.12.190112.136.12.19162
52112.136.12.192/26112.136.12.193 to 112.136.12.254112.136.12.25562
53112.136.13.0/26112.136.13.1 to 112.136.13.62112.136.13.6362
54112.136.13.64/26112.136.13.65 to 112.136.13.126112.136.13.12762
55112.136.13.128/26112.136.13.129 to 112.136.13.190112.136.13.19162
56112.136.13.192/26112.136.13.193 to 112.136.13.254112.136.13.25562
57112.136.14.0/26112.136.14.1 to 112.136.14.62112.136.14.6362
58112.136.14.64/26112.136.14.65 to 112.136.14.126112.136.14.12762
59112.136.14.128/26112.136.14.129 to 112.136.14.190112.136.14.19162
60112.136.14.192/26112.136.14.193 to 112.136.14.254112.136.14.25562
61112.136.15.0/26112.136.15.1 to 112.136.15.62112.136.15.6362
62112.136.15.64/26112.136.15.65 to 112.136.15.126112.136.15.12762
63112.136.15.128/26112.136.15.129 to 112.136.15.190112.136.15.19162
64112.136.15.192/26112.136.15.193 to 112.136.15.254112.136.15.25562
65112.136.16.0/26112.136.16.1 to 112.136.16.62112.136.16.6362
66112.136.16.64/26112.136.16.65 to 112.136.16.126112.136.16.12762
67112.136.16.128/26112.136.16.129 to 112.136.16.190112.136.16.19162
68112.136.16.192/26112.136.16.193 to 112.136.16.254112.136.16.25562
69112.136.17.0/26112.136.17.1 to 112.136.17.62112.136.17.6362
70112.136.17.64/26112.136.17.65 to 112.136.17.126112.136.17.12762
71112.136.17.128/26112.136.17.129 to 112.136.17.190112.136.17.19162
72112.136.17.192/26112.136.17.193 to 112.136.17.254112.136.17.25562
73112.136.18.0/26112.136.18.1 to 112.136.18.62112.136.18.6362
74112.136.18.64/26112.136.18.65 to 112.136.18.126112.136.18.12762
75112.136.18.128/26112.136.18.129 to 112.136.18.190112.136.18.19162
76112.136.18.192/26112.136.18.193 to 112.136.18.254112.136.18.25562
77112.136.19.0/26112.136.19.1 to 112.136.19.62112.136.19.6362
78112.136.19.64/26112.136.19.65 to 112.136.19.126112.136.19.12762
79112.136.19.128/26112.136.19.129 to 112.136.19.190112.136.19.19162
80112.136.19.192/26112.136.19.193 to 112.136.19.254112.136.19.25562
81112.136.20.0/26112.136.20.1 to 112.136.20.62112.136.20.6362
82112.136.20.64/26112.136.20.65 to 112.136.20.126112.136.20.12762
83112.136.20.128/26112.136.20.129 to 112.136.20.190112.136.20.19162
84112.136.20.192/26112.136.20.193 to 112.136.20.254112.136.20.25562
85112.136.21.0/26112.136.21.1 to 112.136.21.62112.136.21.6362
86112.136.21.64/26112.136.21.65 to 112.136.21.126112.136.21.12762
87112.136.21.128/26112.136.21.129 to 112.136.21.190112.136.21.19162
88112.136.21.192/26112.136.21.193 to 112.136.21.254112.136.21.25562
89112.136.22.0/26112.136.22.1 to 112.136.22.62112.136.22.6362
90112.136.22.64/26112.136.22.65 to 112.136.22.126112.136.22.12762
91112.136.22.128/26112.136.22.129 to 112.136.22.190112.136.22.19162
92112.136.22.192/26112.136.22.193 to 112.136.22.254112.136.22.25562
93112.136.23.0/26112.136.23.1 to 112.136.23.62112.136.23.6362
94112.136.23.64/26112.136.23.65 to 112.136.23.126112.136.23.12762
95112.136.23.128/26112.136.23.129 to 112.136.23.190112.136.23.19162
96112.136.23.192/26112.136.23.193 to 112.136.23.254112.136.23.25562
97112.136.24.0/26112.136.24.1 to 112.136.24.62112.136.24.6362
98112.136.24.64/26112.136.24.65 to 112.136.24.126112.136.24.12762
99112.136.24.128/26112.136.24.129 to 112.136.24.190112.136.24.19162
100112.136.24.192/26112.136.24.193 to 112.136.24.254112.136.24.25562
101112.136.25.0/26112.136.25.1 to 112.136.25.62112.136.25.6362
102112.136.25.64/26112.136.25.65 to 112.136.25.126112.136.25.12762
103112.136.25.128/26112.136.25.129 to 112.136.25.190112.136.25.19162
104112.136.25.192/26112.136.25.193 to 112.136.25.254112.136.25.25562
105112.136.26.0/26112.136.26.1 to 112.136.26.62112.136.26.6362
106112.136.26.64/26112.136.26.65 to 112.136.26.126112.136.26.12762
107112.136.26.128/26112.136.26.129 to 112.136.26.190112.136.26.19162
108112.136.26.192/26112.136.26.193 to 112.136.26.254112.136.26.25562
109112.136.27.0/26112.136.27.1 to 112.136.27.62112.136.27.6362
110112.136.27.64/26112.136.27.65 to 112.136.27.126112.136.27.12762
111112.136.27.128/26112.136.27.129 to 112.136.27.190112.136.27.19162
112112.136.27.192/26112.136.27.193 to 112.136.27.254112.136.27.25562
113112.136.28.0/26112.136.28.1 to 112.136.28.62112.136.28.6362
114112.136.28.64/26112.136.28.65 to 112.136.28.126112.136.28.12762
115112.136.28.128/26112.136.28.129 to 112.136.28.190112.136.28.19162
116112.136.28.192/26112.136.28.193 to 112.136.28.254112.136.28.25562
117112.136.29.0/26112.136.29.1 to 112.136.29.62112.136.29.6362
118112.136.29.64/26112.136.29.65 to 112.136.29.126112.136.29.12762
119112.136.29.128/26112.136.29.129 to 112.136.29.190112.136.29.19162
120112.136.29.192/26112.136.29.193 to 112.136.29.254112.136.29.25562
121112.136.30.0/26112.136.30.1 to 112.136.30.62112.136.30.6362
122112.136.30.64/26112.136.30.65 to 112.136.30.126112.136.30.12762
123112.136.30.128/26112.136.30.129 to 112.136.30.190112.136.30.19162
124112.136.30.192/26112.136.30.193 to 112.136.30.254112.136.30.25562
125112.136.31.0/26112.136.31.1 to 112.136.31.62112.136.31.6362
126112.136.31.64/26112.136.31.65 to 112.136.31.126112.136.31.12762
127112.136.31.128/26112.136.31.129 to 112.136.31.190112.136.31.19162
128112.136.31.192/26112.136.31.193 to 112.136.31.254112.136.31.25562
129112.136.32.0/26112.136.32.1 to 112.136.32.62112.136.32.6362
130112.136.32.64/26112.136.32.65 to 112.136.32.126112.136.32.12762
131112.136.32.128/26112.136.32.129 to 112.136.32.190112.136.32.19162
132112.136.32.192/26112.136.32.193 to 112.136.32.254112.136.32.25562
133112.136.33.0/26112.136.33.1 to 112.136.33.62112.136.33.6362
134112.136.33.64/26112.136.33.65 to 112.136.33.126112.136.33.12762
135112.136.33.128/26112.136.33.129 to 112.136.33.190112.136.33.19162
136112.136.33.192/26112.136.33.193 to 112.136.33.254112.136.33.25562
137112.136.34.0/26112.136.34.1 to 112.136.34.62112.136.34.6362
138112.136.34.64/26112.136.34.65 to 112.136.34.126112.136.34.12762
139112.136.34.128/26112.136.34.129 to 112.136.34.190112.136.34.19162
140112.136.34.192/26112.136.34.193 to 112.136.34.254112.136.34.25562
141112.136.35.0/26112.136.35.1 to 112.136.35.62112.136.35.6362
142112.136.35.64/26112.136.35.65 to 112.136.35.126112.136.35.12762
143112.136.35.128/26112.136.35.129 to 112.136.35.190112.136.35.19162
144112.136.35.192/26112.136.35.193 to 112.136.35.254112.136.35.25562
145112.136.36.0/26112.136.36.1 to 112.136.36.62112.136.36.6362
146112.136.36.64/26112.136.36.65 to 112.136.36.126112.136.36.12762
147112.136.36.128/26112.136.36.129 to 112.136.36.190112.136.36.19162
148112.136.36.192/26112.136.36.193 to 112.136.36.254112.136.36.25562
149112.136.37.0/26112.136.37.1 to 112.136.37.62112.136.37.6362
150112.136.37.64/26112.136.37.65 to 112.136.37.126112.136.37.12762
151112.136.37.128/26112.136.37.129 to 112.136.37.190112.136.37.19162
152112.136.37.192/26112.136.37.193 to 112.136.37.254112.136.37.25562
153112.136.38.0/26112.136.38.1 to 112.136.38.62112.136.38.6362
154112.136.38.64/26112.136.38.65 to 112.136.38.126112.136.38.12762
155112.136.38.128/26112.136.38.129 to 112.136.38.190112.136.38.19162
156112.136.38.192/26112.136.38.193 to 112.136.38.254112.136.38.25562
157112.136.39.0/26112.136.39.1 to 112.136.39.62112.136.39.6362
158112.136.39.64/26112.136.39.65 to 112.136.39.126112.136.39.12762
159112.136.39.128/26112.136.39.129 to 112.136.39.190112.136.39.19162
160112.136.39.192/26112.136.39.193 to 112.136.39.254112.136.39.25562
161112.136.40.0/26112.136.40.1 to 112.136.40.62112.136.40.6362
162112.136.40.64/26112.136.40.65 to 112.136.40.126112.136.40.12762
163112.136.40.128/26112.136.40.129 to 112.136.40.190112.136.40.19162
164112.136.40.192/26112.136.40.193 to 112.136.40.254112.136.40.25562
165112.136.41.0/26112.136.41.1 to 112.136.41.62112.136.41.6362
166112.136.41.64/26112.136.41.65 to 112.136.41.126112.136.41.12762
167112.136.41.128/26112.136.41.129 to 112.136.41.190112.136.41.19162
168112.136.41.192/26112.136.41.193 to 112.136.41.254112.136.41.25562
169112.136.42.0/26112.136.42.1 to 112.136.42.62112.136.42.6362
170112.136.42.64/26112.136.42.65 to 112.136.42.126112.136.42.12762
171112.136.42.128/26112.136.42.129 to 112.136.42.190112.136.42.19162
172112.136.42.192/26112.136.42.193 to 112.136.42.254112.136.42.25562
173112.136.43.0/26112.136.43.1 to 112.136.43.62112.136.43.6362
174112.136.43.64/26112.136.43.65 to 112.136.43.126112.136.43.12762
175112.136.43.128/26112.136.43.129 to 112.136.43.190112.136.43.19162
176112.136.43.192/26112.136.43.193 to 112.136.43.254112.136.43.25562
177112.136.44.0/26112.136.44.1 to 112.136.44.62112.136.44.6362
178112.136.44.64/26112.136.44.65 to 112.136.44.126112.136.44.12762
179112.136.44.128/26112.136.44.129 to 112.136.44.190112.136.44.19162
180112.136.44.192/26112.136.44.193 to 112.136.44.254112.136.44.25562
181112.136.45.0/26112.136.45.1 to 112.136.45.62112.136.45.6362
182112.136.45.64/26112.136.45.65 to 112.136.45.126112.136.45.12762
183112.136.45.128/26112.136.45.129 to 112.136.45.190112.136.45.19162
184112.136.45.192/26112.136.45.193 to 112.136.45.254112.136.45.25562
185112.136.46.0/26112.136.46.1 to 112.136.46.62112.136.46.6362
186112.136.46.64/26112.136.46.65 to 112.136.46.126112.136.46.12762
187112.136.46.128/26112.136.46.129 to 112.136.46.190112.136.46.19162
188112.136.46.192/26112.136.46.193 to 112.136.46.254112.136.46.25562
189112.136.47.0/26112.136.47.1 to 112.136.47.62112.136.47.6362
190112.136.47.64/26112.136.47.65 to 112.136.47.126112.136.47.12762
191112.136.47.128/26112.136.47.129 to 112.136.47.190112.136.47.19162
192112.136.47.192/26112.136.47.193 to 112.136.47.254112.136.47.25562
193112.136.48.0/26112.136.48.1 to 112.136.48.62112.136.48.6362
194112.136.48.64/26112.136.48.65 to 112.136.48.126112.136.48.12762
195112.136.48.128/26112.136.48.129 to 112.136.48.190112.136.48.19162
196112.136.48.192/26112.136.48.193 to 112.136.48.254112.136.48.25562
197112.136.49.0/26112.136.49.1 to 112.136.49.62112.136.49.6362
198112.136.49.64/26112.136.49.65 to 112.136.49.126112.136.49.12762
199112.136.49.128/26112.136.49.129 to 112.136.49.190112.136.49.19162
200112.136.49.192/26112.136.49.193 to 112.136.49.254112.136.49.25562
201112.136.50.0/26112.136.50.1 to 112.136.50.62112.136.50.6362
202112.136.50.64/26112.136.50.65 to 112.136.50.126112.136.50.12762
203112.136.50.128/26112.136.50.129 to 112.136.50.190112.136.50.19162
204112.136.50.192/26112.136.50.193 to 112.136.50.254112.136.50.25562
205112.136.51.0/26112.136.51.1 to 112.136.51.62112.136.51.6362
206112.136.51.64/26112.136.51.65 to 112.136.51.126112.136.51.12762
207112.136.51.128/26112.136.51.129 to 112.136.51.190112.136.51.19162
208112.136.51.192/26112.136.51.193 to 112.136.51.254112.136.51.25562
209112.136.52.0/26112.136.52.1 to 112.136.52.62112.136.52.6362
210112.136.52.64/26112.136.52.65 to 112.136.52.126112.136.52.12762
211112.136.52.128/26112.136.52.129 to 112.136.52.190112.136.52.19162
212112.136.52.192/26112.136.52.193 to 112.136.52.254112.136.52.25562
213112.136.53.0/26112.136.53.1 to 112.136.53.62112.136.53.6362
214112.136.53.64/26112.136.53.65 to 112.136.53.126112.136.53.12762
215112.136.53.128/26112.136.53.129 to 112.136.53.190112.136.53.19162
216112.136.53.192/26112.136.53.193 to 112.136.53.254112.136.53.25562
217112.136.54.0/26112.136.54.1 to 112.136.54.62112.136.54.6362
218112.136.54.64/26112.136.54.65 to 112.136.54.126112.136.54.12762
219112.136.54.128/26112.136.54.129 to 112.136.54.190112.136.54.19162
220112.136.54.192/26112.136.54.193 to 112.136.54.254112.136.54.25562
221112.136.55.0/26112.136.55.1 to 112.136.55.62112.136.55.6362
222112.136.55.64/26112.136.55.65 to 112.136.55.126112.136.55.12762
223112.136.55.128/26112.136.55.129 to 112.136.55.190112.136.55.19162
224112.136.55.192/26112.136.55.193 to 112.136.55.254112.136.55.25562
225112.136.56.0/26112.136.56.1 to 112.136.56.62112.136.56.6362
226112.136.56.64/26112.136.56.65 to 112.136.56.126112.136.56.12762
227112.136.56.128/26112.136.56.129 to 112.136.56.190112.136.56.19162
228112.136.56.192/26112.136.56.193 to 112.136.56.254112.136.56.25562
229112.136.57.0/26112.136.57.1 to 112.136.57.62112.136.57.6362
230112.136.57.64/26112.136.57.65 to 112.136.57.126112.136.57.12762
231112.136.57.128/26112.136.57.129 to 112.136.57.190112.136.57.19162
232112.136.57.192/26112.136.57.193 to 112.136.57.254112.136.57.25562
233112.136.58.0/26112.136.58.1 to 112.136.58.62112.136.58.6362
234112.136.58.64/26112.136.58.65 to 112.136.58.126112.136.58.12762
235112.136.58.128/26112.136.58.129 to 112.136.58.190112.136.58.19162
236112.136.58.192/26112.136.58.193 to 112.136.58.254112.136.58.25562
237112.136.59.0/26112.136.59.1 to 112.136.59.62112.136.59.6362
238112.136.59.64/26112.136.59.65 to 112.136.59.126112.136.59.12762
239112.136.59.128/26112.136.59.129 to 112.136.59.190112.136.59.19162
240112.136.59.192/26112.136.59.193 to 112.136.59.254112.136.59.25562
241112.136.60.0/26112.136.60.1 to 112.136.60.62112.136.60.6362
242112.136.60.64/26112.136.60.65 to 112.136.60.126112.136.60.12762
243112.136.60.128/26112.136.60.129 to 112.136.60.190112.136.60.19162
244112.136.60.192/26112.136.60.193 to 112.136.60.254112.136.60.25562
245112.136.61.0/26112.136.61.1 to 112.136.61.62112.136.61.6362
246112.136.61.64/26112.136.61.65 to 112.136.61.126112.136.61.12762
247112.136.61.128/26112.136.61.129 to 112.136.61.190112.136.61.19162
248112.136.61.192/26112.136.61.193 to 112.136.61.254112.136.61.25562
249112.136.62.0/26112.136.62.1 to 112.136.62.62112.136.62.6362
250112.136.62.64/26112.136.62.65 to 112.136.62.126112.136.62.12762
251112.136.62.128/26112.136.62.129 to 112.136.62.190112.136.62.19162
252112.136.62.192/26112.136.62.193 to 112.136.62.254112.136.62.25562
253112.136.63.0/26112.136.63.1 to 112.136.63.62112.136.63.6362
254112.136.63.64/26112.136.63.65 to 112.136.63.126112.136.63.12762
255112.136.63.128/26112.136.63.129 to 112.136.63.190112.136.63.19162
256112.136.63.192/26112.136.63.193 to 112.136.63.254112.136.63.25562

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.