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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.

Network142.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
142.0.0.0
Broadcast address
142.255.255.255
First usable
142.0.0.1
Last usable
142.255.255.254
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
B (default /16)
As numbers
Hex 8E000000 · Integer 2382364672 to 2399141887
Reverse DNS zone
142.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10001110..00000000.00000000.00000000142.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10001110..00000000.00000000.00000000142.0.0.0
Broadcast10001110..11111111.11111111.11111111142.255.255.255
Split into smaller subnets/18
/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)

142.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1142.0.0.0/18142.0.0.1 to 142.0.63.254142.0.63.25516,382
2142.0.64.0/18142.0.64.1 to 142.0.127.254142.0.127.25516,382
3142.0.128.0/18142.0.128.1 to 142.0.191.254142.0.191.25516,382
4142.0.192.0/18142.0.192.1 to 142.0.255.254142.0.255.25516,382
5142.1.0.0/18142.1.0.1 to 142.1.63.254142.1.63.25516,382
6142.1.64.0/18142.1.64.1 to 142.1.127.254142.1.127.25516,382
7142.1.128.0/18142.1.128.1 to 142.1.191.254142.1.191.25516,382
8142.1.192.0/18142.1.192.1 to 142.1.255.254142.1.255.25516,382
9142.2.0.0/18142.2.0.1 to 142.2.63.254142.2.63.25516,382
10142.2.64.0/18142.2.64.1 to 142.2.127.254142.2.127.25516,382
11142.2.128.0/18142.2.128.1 to 142.2.191.254142.2.191.25516,382
12142.2.192.0/18142.2.192.1 to 142.2.255.254142.2.255.25516,382
13142.3.0.0/18142.3.0.1 to 142.3.63.254142.3.63.25516,382
14142.3.64.0/18142.3.64.1 to 142.3.127.254142.3.127.25516,382
15142.3.128.0/18142.3.128.1 to 142.3.191.254142.3.191.25516,382
16142.3.192.0/18142.3.192.1 to 142.3.255.254142.3.255.25516,382
17142.4.0.0/18142.4.0.1 to 142.4.63.254142.4.63.25516,382
18142.4.64.0/18142.4.64.1 to 142.4.127.254142.4.127.25516,382
19142.4.128.0/18142.4.128.1 to 142.4.191.254142.4.191.25516,382
20142.4.192.0/18142.4.192.1 to 142.4.255.254142.4.255.25516,382
21142.5.0.0/18142.5.0.1 to 142.5.63.254142.5.63.25516,382
22142.5.64.0/18142.5.64.1 to 142.5.127.254142.5.127.25516,382
23142.5.128.0/18142.5.128.1 to 142.5.191.254142.5.191.25516,382
24142.5.192.0/18142.5.192.1 to 142.5.255.254142.5.255.25516,382
25142.6.0.0/18142.6.0.1 to 142.6.63.254142.6.63.25516,382
26142.6.64.0/18142.6.64.1 to 142.6.127.254142.6.127.25516,382
27142.6.128.0/18142.6.128.1 to 142.6.191.254142.6.191.25516,382
28142.6.192.0/18142.6.192.1 to 142.6.255.254142.6.255.25516,382
29142.7.0.0/18142.7.0.1 to 142.7.63.254142.7.63.25516,382
30142.7.64.0/18142.7.64.1 to 142.7.127.254142.7.127.25516,382
31142.7.128.0/18142.7.128.1 to 142.7.191.254142.7.191.25516,382
32142.7.192.0/18142.7.192.1 to 142.7.255.254142.7.255.25516,382
33142.8.0.0/18142.8.0.1 to 142.8.63.254142.8.63.25516,382
34142.8.64.0/18142.8.64.1 to 142.8.127.254142.8.127.25516,382
35142.8.128.0/18142.8.128.1 to 142.8.191.254142.8.191.25516,382
36142.8.192.0/18142.8.192.1 to 142.8.255.254142.8.255.25516,382
37142.9.0.0/18142.9.0.1 to 142.9.63.254142.9.63.25516,382
38142.9.64.0/18142.9.64.1 to 142.9.127.254142.9.127.25516,382
39142.9.128.0/18142.9.128.1 to 142.9.191.254142.9.191.25516,382
40142.9.192.0/18142.9.192.1 to 142.9.255.254142.9.255.25516,382
41142.10.0.0/18142.10.0.1 to 142.10.63.254142.10.63.25516,382
42142.10.64.0/18142.10.64.1 to 142.10.127.254142.10.127.25516,382
43142.10.128.0/18142.10.128.1 to 142.10.191.254142.10.191.25516,382
44142.10.192.0/18142.10.192.1 to 142.10.255.254142.10.255.25516,382
45142.11.0.0/18142.11.0.1 to 142.11.63.254142.11.63.25516,382
46142.11.64.0/18142.11.64.1 to 142.11.127.254142.11.127.25516,382
47142.11.128.0/18142.11.128.1 to 142.11.191.254142.11.191.25516,382
48142.11.192.0/18142.11.192.1 to 142.11.255.254142.11.255.25516,382
49142.12.0.0/18142.12.0.1 to 142.12.63.254142.12.63.25516,382
50142.12.64.0/18142.12.64.1 to 142.12.127.254142.12.127.25516,382
51142.12.128.0/18142.12.128.1 to 142.12.191.254142.12.191.25516,382
52142.12.192.0/18142.12.192.1 to 142.12.255.254142.12.255.25516,382
53142.13.0.0/18142.13.0.1 to 142.13.63.254142.13.63.25516,382
54142.13.64.0/18142.13.64.1 to 142.13.127.254142.13.127.25516,382
55142.13.128.0/18142.13.128.1 to 142.13.191.254142.13.191.25516,382
56142.13.192.0/18142.13.192.1 to 142.13.255.254142.13.255.25516,382
57142.14.0.0/18142.14.0.1 to 142.14.63.254142.14.63.25516,382
58142.14.64.0/18142.14.64.1 to 142.14.127.254142.14.127.25516,382
59142.14.128.0/18142.14.128.1 to 142.14.191.254142.14.191.25516,382
60142.14.192.0/18142.14.192.1 to 142.14.255.254142.14.255.25516,382
61142.15.0.0/18142.15.0.1 to 142.15.63.254142.15.63.25516,382
62142.15.64.0/18142.15.64.1 to 142.15.127.254142.15.127.25516,382
63142.15.128.0/18142.15.128.1 to 142.15.191.254142.15.191.25516,382
64142.15.192.0/18142.15.192.1 to 142.15.255.254142.15.255.25516,382
65142.16.0.0/18142.16.0.1 to 142.16.63.254142.16.63.25516,382
66142.16.64.0/18142.16.64.1 to 142.16.127.254142.16.127.25516,382
67142.16.128.0/18142.16.128.1 to 142.16.191.254142.16.191.25516,382
68142.16.192.0/18142.16.192.1 to 142.16.255.254142.16.255.25516,382
69142.17.0.0/18142.17.0.1 to 142.17.63.254142.17.63.25516,382
70142.17.64.0/18142.17.64.1 to 142.17.127.254142.17.127.25516,382
71142.17.128.0/18142.17.128.1 to 142.17.191.254142.17.191.25516,382
72142.17.192.0/18142.17.192.1 to 142.17.255.254142.17.255.25516,382
73142.18.0.0/18142.18.0.1 to 142.18.63.254142.18.63.25516,382
74142.18.64.0/18142.18.64.1 to 142.18.127.254142.18.127.25516,382
75142.18.128.0/18142.18.128.1 to 142.18.191.254142.18.191.25516,382
76142.18.192.0/18142.18.192.1 to 142.18.255.254142.18.255.25516,382
77142.19.0.0/18142.19.0.1 to 142.19.63.254142.19.63.25516,382
78142.19.64.0/18142.19.64.1 to 142.19.127.254142.19.127.25516,382
79142.19.128.0/18142.19.128.1 to 142.19.191.254142.19.191.25516,382
80142.19.192.0/18142.19.192.1 to 142.19.255.254142.19.255.25516,382
81142.20.0.0/18142.20.0.1 to 142.20.63.254142.20.63.25516,382
82142.20.64.0/18142.20.64.1 to 142.20.127.254142.20.127.25516,382
83142.20.128.0/18142.20.128.1 to 142.20.191.254142.20.191.25516,382
84142.20.192.0/18142.20.192.1 to 142.20.255.254142.20.255.25516,382
85142.21.0.0/18142.21.0.1 to 142.21.63.254142.21.63.25516,382
86142.21.64.0/18142.21.64.1 to 142.21.127.254142.21.127.25516,382
87142.21.128.0/18142.21.128.1 to 142.21.191.254142.21.191.25516,382
88142.21.192.0/18142.21.192.1 to 142.21.255.254142.21.255.25516,382
89142.22.0.0/18142.22.0.1 to 142.22.63.254142.22.63.25516,382
90142.22.64.0/18142.22.64.1 to 142.22.127.254142.22.127.25516,382
91142.22.128.0/18142.22.128.1 to 142.22.191.254142.22.191.25516,382
92142.22.192.0/18142.22.192.1 to 142.22.255.254142.22.255.25516,382
93142.23.0.0/18142.23.0.1 to 142.23.63.254142.23.63.25516,382
94142.23.64.0/18142.23.64.1 to 142.23.127.254142.23.127.25516,382
95142.23.128.0/18142.23.128.1 to 142.23.191.254142.23.191.25516,382
96142.23.192.0/18142.23.192.1 to 142.23.255.254142.23.255.25516,382
97142.24.0.0/18142.24.0.1 to 142.24.63.254142.24.63.25516,382
98142.24.64.0/18142.24.64.1 to 142.24.127.254142.24.127.25516,382
99142.24.128.0/18142.24.128.1 to 142.24.191.254142.24.191.25516,382
100142.24.192.0/18142.24.192.1 to 142.24.255.254142.24.255.25516,382
101142.25.0.0/18142.25.0.1 to 142.25.63.254142.25.63.25516,382
102142.25.64.0/18142.25.64.1 to 142.25.127.254142.25.127.25516,382
103142.25.128.0/18142.25.128.1 to 142.25.191.254142.25.191.25516,382
104142.25.192.0/18142.25.192.1 to 142.25.255.254142.25.255.25516,382
105142.26.0.0/18142.26.0.1 to 142.26.63.254142.26.63.25516,382
106142.26.64.0/18142.26.64.1 to 142.26.127.254142.26.127.25516,382
107142.26.128.0/18142.26.128.1 to 142.26.191.254142.26.191.25516,382
108142.26.192.0/18142.26.192.1 to 142.26.255.254142.26.255.25516,382
109142.27.0.0/18142.27.0.1 to 142.27.63.254142.27.63.25516,382
110142.27.64.0/18142.27.64.1 to 142.27.127.254142.27.127.25516,382
111142.27.128.0/18142.27.128.1 to 142.27.191.254142.27.191.25516,382
112142.27.192.0/18142.27.192.1 to 142.27.255.254142.27.255.25516,382
113142.28.0.0/18142.28.0.1 to 142.28.63.254142.28.63.25516,382
114142.28.64.0/18142.28.64.1 to 142.28.127.254142.28.127.25516,382
115142.28.128.0/18142.28.128.1 to 142.28.191.254142.28.191.25516,382
116142.28.192.0/18142.28.192.1 to 142.28.255.254142.28.255.25516,382
117142.29.0.0/18142.29.0.1 to 142.29.63.254142.29.63.25516,382
118142.29.64.0/18142.29.64.1 to 142.29.127.254142.29.127.25516,382
119142.29.128.0/18142.29.128.1 to 142.29.191.254142.29.191.25516,382
120142.29.192.0/18142.29.192.1 to 142.29.255.254142.29.255.25516,382
121142.30.0.0/18142.30.0.1 to 142.30.63.254142.30.63.25516,382
122142.30.64.0/18142.30.64.1 to 142.30.127.254142.30.127.25516,382
123142.30.128.0/18142.30.128.1 to 142.30.191.254142.30.191.25516,382
124142.30.192.0/18142.30.192.1 to 142.30.255.254142.30.255.25516,382
125142.31.0.0/18142.31.0.1 to 142.31.63.254142.31.63.25516,382
126142.31.64.0/18142.31.64.1 to 142.31.127.254142.31.127.25516,382
127142.31.128.0/18142.31.128.1 to 142.31.191.254142.31.191.25516,382
128142.31.192.0/18142.31.192.1 to 142.31.255.254142.31.255.25516,382
129142.32.0.0/18142.32.0.1 to 142.32.63.254142.32.63.25516,382
130142.32.64.0/18142.32.64.1 to 142.32.127.254142.32.127.25516,382
131142.32.128.0/18142.32.128.1 to 142.32.191.254142.32.191.25516,382
132142.32.192.0/18142.32.192.1 to 142.32.255.254142.32.255.25516,382
133142.33.0.0/18142.33.0.1 to 142.33.63.254142.33.63.25516,382
134142.33.64.0/18142.33.64.1 to 142.33.127.254142.33.127.25516,382
135142.33.128.0/18142.33.128.1 to 142.33.191.254142.33.191.25516,382
136142.33.192.0/18142.33.192.1 to 142.33.255.254142.33.255.25516,382
137142.34.0.0/18142.34.0.1 to 142.34.63.254142.34.63.25516,382
138142.34.64.0/18142.34.64.1 to 142.34.127.254142.34.127.25516,382
139142.34.128.0/18142.34.128.1 to 142.34.191.254142.34.191.25516,382
140142.34.192.0/18142.34.192.1 to 142.34.255.254142.34.255.25516,382
141142.35.0.0/18142.35.0.1 to 142.35.63.254142.35.63.25516,382
142142.35.64.0/18142.35.64.1 to 142.35.127.254142.35.127.25516,382
143142.35.128.0/18142.35.128.1 to 142.35.191.254142.35.191.25516,382
144142.35.192.0/18142.35.192.1 to 142.35.255.254142.35.255.25516,382
145142.36.0.0/18142.36.0.1 to 142.36.63.254142.36.63.25516,382
146142.36.64.0/18142.36.64.1 to 142.36.127.254142.36.127.25516,382
147142.36.128.0/18142.36.128.1 to 142.36.191.254142.36.191.25516,382
148142.36.192.0/18142.36.192.1 to 142.36.255.254142.36.255.25516,382
149142.37.0.0/18142.37.0.1 to 142.37.63.254142.37.63.25516,382
150142.37.64.0/18142.37.64.1 to 142.37.127.254142.37.127.25516,382
151142.37.128.0/18142.37.128.1 to 142.37.191.254142.37.191.25516,382
152142.37.192.0/18142.37.192.1 to 142.37.255.254142.37.255.25516,382
153142.38.0.0/18142.38.0.1 to 142.38.63.254142.38.63.25516,382
154142.38.64.0/18142.38.64.1 to 142.38.127.254142.38.127.25516,382
155142.38.128.0/18142.38.128.1 to 142.38.191.254142.38.191.25516,382
156142.38.192.0/18142.38.192.1 to 142.38.255.254142.38.255.25516,382
157142.39.0.0/18142.39.0.1 to 142.39.63.254142.39.63.25516,382
158142.39.64.0/18142.39.64.1 to 142.39.127.254142.39.127.25516,382
159142.39.128.0/18142.39.128.1 to 142.39.191.254142.39.191.25516,382
160142.39.192.0/18142.39.192.1 to 142.39.255.254142.39.255.25516,382
161142.40.0.0/18142.40.0.1 to 142.40.63.254142.40.63.25516,382
162142.40.64.0/18142.40.64.1 to 142.40.127.254142.40.127.25516,382
163142.40.128.0/18142.40.128.1 to 142.40.191.254142.40.191.25516,382
164142.40.192.0/18142.40.192.1 to 142.40.255.254142.40.255.25516,382
165142.41.0.0/18142.41.0.1 to 142.41.63.254142.41.63.25516,382
166142.41.64.0/18142.41.64.1 to 142.41.127.254142.41.127.25516,382
167142.41.128.0/18142.41.128.1 to 142.41.191.254142.41.191.25516,382
168142.41.192.0/18142.41.192.1 to 142.41.255.254142.41.255.25516,382
169142.42.0.0/18142.42.0.1 to 142.42.63.254142.42.63.25516,382
170142.42.64.0/18142.42.64.1 to 142.42.127.254142.42.127.25516,382
171142.42.128.0/18142.42.128.1 to 142.42.191.254142.42.191.25516,382
172142.42.192.0/18142.42.192.1 to 142.42.255.254142.42.255.25516,382
173142.43.0.0/18142.43.0.1 to 142.43.63.254142.43.63.25516,382
174142.43.64.0/18142.43.64.1 to 142.43.127.254142.43.127.25516,382
175142.43.128.0/18142.43.128.1 to 142.43.191.254142.43.191.25516,382
176142.43.192.0/18142.43.192.1 to 142.43.255.254142.43.255.25516,382
177142.44.0.0/18142.44.0.1 to 142.44.63.254142.44.63.25516,382
178142.44.64.0/18142.44.64.1 to 142.44.127.254142.44.127.25516,382
179142.44.128.0/18142.44.128.1 to 142.44.191.254142.44.191.25516,382
180142.44.192.0/18142.44.192.1 to 142.44.255.254142.44.255.25516,382
181142.45.0.0/18142.45.0.1 to 142.45.63.254142.45.63.25516,382
182142.45.64.0/18142.45.64.1 to 142.45.127.254142.45.127.25516,382
183142.45.128.0/18142.45.128.1 to 142.45.191.254142.45.191.25516,382
184142.45.192.0/18142.45.192.1 to 142.45.255.254142.45.255.25516,382
185142.46.0.0/18142.46.0.1 to 142.46.63.254142.46.63.25516,382
186142.46.64.0/18142.46.64.1 to 142.46.127.254142.46.127.25516,382
187142.46.128.0/18142.46.128.1 to 142.46.191.254142.46.191.25516,382
188142.46.192.0/18142.46.192.1 to 142.46.255.254142.46.255.25516,382
189142.47.0.0/18142.47.0.1 to 142.47.63.254142.47.63.25516,382
190142.47.64.0/18142.47.64.1 to 142.47.127.254142.47.127.25516,382
191142.47.128.0/18142.47.128.1 to 142.47.191.254142.47.191.25516,382
192142.47.192.0/18142.47.192.1 to 142.47.255.254142.47.255.25516,382
193142.48.0.0/18142.48.0.1 to 142.48.63.254142.48.63.25516,382
194142.48.64.0/18142.48.64.1 to 142.48.127.254142.48.127.25516,382
195142.48.128.0/18142.48.128.1 to 142.48.191.254142.48.191.25516,382
196142.48.192.0/18142.48.192.1 to 142.48.255.254142.48.255.25516,382
197142.49.0.0/18142.49.0.1 to 142.49.63.254142.49.63.25516,382
198142.49.64.0/18142.49.64.1 to 142.49.127.254142.49.127.25516,382
199142.49.128.0/18142.49.128.1 to 142.49.191.254142.49.191.25516,382
200142.49.192.0/18142.49.192.1 to 142.49.255.254142.49.255.25516,382
201142.50.0.0/18142.50.0.1 to 142.50.63.254142.50.63.25516,382
202142.50.64.0/18142.50.64.1 to 142.50.127.254142.50.127.25516,382
203142.50.128.0/18142.50.128.1 to 142.50.191.254142.50.191.25516,382
204142.50.192.0/18142.50.192.1 to 142.50.255.254142.50.255.25516,382
205142.51.0.0/18142.51.0.1 to 142.51.63.254142.51.63.25516,382
206142.51.64.0/18142.51.64.1 to 142.51.127.254142.51.127.25516,382
207142.51.128.0/18142.51.128.1 to 142.51.191.254142.51.191.25516,382
208142.51.192.0/18142.51.192.1 to 142.51.255.254142.51.255.25516,382
209142.52.0.0/18142.52.0.1 to 142.52.63.254142.52.63.25516,382
210142.52.64.0/18142.52.64.1 to 142.52.127.254142.52.127.25516,382
211142.52.128.0/18142.52.128.1 to 142.52.191.254142.52.191.25516,382
212142.52.192.0/18142.52.192.1 to 142.52.255.254142.52.255.25516,382
213142.53.0.0/18142.53.0.1 to 142.53.63.254142.53.63.25516,382
214142.53.64.0/18142.53.64.1 to 142.53.127.254142.53.127.25516,382
215142.53.128.0/18142.53.128.1 to 142.53.191.254142.53.191.25516,382
216142.53.192.0/18142.53.192.1 to 142.53.255.254142.53.255.25516,382
217142.54.0.0/18142.54.0.1 to 142.54.63.254142.54.63.25516,382
218142.54.64.0/18142.54.64.1 to 142.54.127.254142.54.127.25516,382
219142.54.128.0/18142.54.128.1 to 142.54.191.254142.54.191.25516,382
220142.54.192.0/18142.54.192.1 to 142.54.255.254142.54.255.25516,382
221142.55.0.0/18142.55.0.1 to 142.55.63.254142.55.63.25516,382
222142.55.64.0/18142.55.64.1 to 142.55.127.254142.55.127.25516,382
223142.55.128.0/18142.55.128.1 to 142.55.191.254142.55.191.25516,382
224142.55.192.0/18142.55.192.1 to 142.55.255.254142.55.255.25516,382
225142.56.0.0/18142.56.0.1 to 142.56.63.254142.56.63.25516,382
226142.56.64.0/18142.56.64.1 to 142.56.127.254142.56.127.25516,382
227142.56.128.0/18142.56.128.1 to 142.56.191.254142.56.191.25516,382
228142.56.192.0/18142.56.192.1 to 142.56.255.254142.56.255.25516,382
229142.57.0.0/18142.57.0.1 to 142.57.63.254142.57.63.25516,382
230142.57.64.0/18142.57.64.1 to 142.57.127.254142.57.127.25516,382
231142.57.128.0/18142.57.128.1 to 142.57.191.254142.57.191.25516,382
232142.57.192.0/18142.57.192.1 to 142.57.255.254142.57.255.25516,382
233142.58.0.0/18142.58.0.1 to 142.58.63.254142.58.63.25516,382
234142.58.64.0/18142.58.64.1 to 142.58.127.254142.58.127.25516,382
235142.58.128.0/18142.58.128.1 to 142.58.191.254142.58.191.25516,382
236142.58.192.0/18142.58.192.1 to 142.58.255.254142.58.255.25516,382
237142.59.0.0/18142.59.0.1 to 142.59.63.254142.59.63.25516,382
238142.59.64.0/18142.59.64.1 to 142.59.127.254142.59.127.25516,382
239142.59.128.0/18142.59.128.1 to 142.59.191.254142.59.191.25516,382
240142.59.192.0/18142.59.192.1 to 142.59.255.254142.59.255.25516,382
241142.60.0.0/18142.60.0.1 to 142.60.63.254142.60.63.25516,382
242142.60.64.0/18142.60.64.1 to 142.60.127.254142.60.127.25516,382
243142.60.128.0/18142.60.128.1 to 142.60.191.254142.60.191.25516,382
244142.60.192.0/18142.60.192.1 to 142.60.255.254142.60.255.25516,382
245142.61.0.0/18142.61.0.1 to 142.61.63.254142.61.63.25516,382
246142.61.64.0/18142.61.64.1 to 142.61.127.254142.61.127.25516,382
247142.61.128.0/18142.61.128.1 to 142.61.191.254142.61.191.25516,382
248142.61.192.0/18142.61.192.1 to 142.61.255.254142.61.255.25516,382
249142.62.0.0/18142.62.0.1 to 142.62.63.254142.62.63.25516,382
250142.62.64.0/18142.62.64.1 to 142.62.127.254142.62.127.25516,382
251142.62.128.0/18142.62.128.1 to 142.62.191.254142.62.191.25516,382
252142.62.192.0/18142.62.192.1 to 142.62.255.254142.62.255.25516,382
253142.63.0.0/18142.63.0.1 to 142.63.63.254142.63.63.25516,382
254142.63.64.0/18142.63.64.1 to 142.63.127.254142.63.127.25516,382
255142.63.128.0/18142.63.128.1 to 142.63.191.254142.63.191.25516,382
256142.63.192.0/18142.63.192.1 to 142.63.255.254142.63.255.25516,382

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.