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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.

Network144.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
144.0.0.0
Broadcast address
144.255.255.255
First usable
144.0.0.1
Last usable
144.255.255.254
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 90000000 · Integer 2415919104 to 2432696319
Reverse DNS zone
144.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10010000..00000000.00000000.00000000144.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10010000..00000000.00000000.00000000144.0.0.0
Broadcast10010000..11111111.11111111.11111111144.255.255.255
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)

144.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1144.0.0.0/18144.0.0.1 to 144.0.63.254144.0.63.25516,382
2144.0.64.0/18144.0.64.1 to 144.0.127.254144.0.127.25516,382
3144.0.128.0/18144.0.128.1 to 144.0.191.254144.0.191.25516,382
4144.0.192.0/18144.0.192.1 to 144.0.255.254144.0.255.25516,382
5144.1.0.0/18144.1.0.1 to 144.1.63.254144.1.63.25516,382
6144.1.64.0/18144.1.64.1 to 144.1.127.254144.1.127.25516,382
7144.1.128.0/18144.1.128.1 to 144.1.191.254144.1.191.25516,382
8144.1.192.0/18144.1.192.1 to 144.1.255.254144.1.255.25516,382
9144.2.0.0/18144.2.0.1 to 144.2.63.254144.2.63.25516,382
10144.2.64.0/18144.2.64.1 to 144.2.127.254144.2.127.25516,382
11144.2.128.0/18144.2.128.1 to 144.2.191.254144.2.191.25516,382
12144.2.192.0/18144.2.192.1 to 144.2.255.254144.2.255.25516,382
13144.3.0.0/18144.3.0.1 to 144.3.63.254144.3.63.25516,382
14144.3.64.0/18144.3.64.1 to 144.3.127.254144.3.127.25516,382
15144.3.128.0/18144.3.128.1 to 144.3.191.254144.3.191.25516,382
16144.3.192.0/18144.3.192.1 to 144.3.255.254144.3.255.25516,382
17144.4.0.0/18144.4.0.1 to 144.4.63.254144.4.63.25516,382
18144.4.64.0/18144.4.64.1 to 144.4.127.254144.4.127.25516,382
19144.4.128.0/18144.4.128.1 to 144.4.191.254144.4.191.25516,382
20144.4.192.0/18144.4.192.1 to 144.4.255.254144.4.255.25516,382
21144.5.0.0/18144.5.0.1 to 144.5.63.254144.5.63.25516,382
22144.5.64.0/18144.5.64.1 to 144.5.127.254144.5.127.25516,382
23144.5.128.0/18144.5.128.1 to 144.5.191.254144.5.191.25516,382
24144.5.192.0/18144.5.192.1 to 144.5.255.254144.5.255.25516,382
25144.6.0.0/18144.6.0.1 to 144.6.63.254144.6.63.25516,382
26144.6.64.0/18144.6.64.1 to 144.6.127.254144.6.127.25516,382
27144.6.128.0/18144.6.128.1 to 144.6.191.254144.6.191.25516,382
28144.6.192.0/18144.6.192.1 to 144.6.255.254144.6.255.25516,382
29144.7.0.0/18144.7.0.1 to 144.7.63.254144.7.63.25516,382
30144.7.64.0/18144.7.64.1 to 144.7.127.254144.7.127.25516,382
31144.7.128.0/18144.7.128.1 to 144.7.191.254144.7.191.25516,382
32144.7.192.0/18144.7.192.1 to 144.7.255.254144.7.255.25516,382
33144.8.0.0/18144.8.0.1 to 144.8.63.254144.8.63.25516,382
34144.8.64.0/18144.8.64.1 to 144.8.127.254144.8.127.25516,382
35144.8.128.0/18144.8.128.1 to 144.8.191.254144.8.191.25516,382
36144.8.192.0/18144.8.192.1 to 144.8.255.254144.8.255.25516,382
37144.9.0.0/18144.9.0.1 to 144.9.63.254144.9.63.25516,382
38144.9.64.0/18144.9.64.1 to 144.9.127.254144.9.127.25516,382
39144.9.128.0/18144.9.128.1 to 144.9.191.254144.9.191.25516,382
40144.9.192.0/18144.9.192.1 to 144.9.255.254144.9.255.25516,382
41144.10.0.0/18144.10.0.1 to 144.10.63.254144.10.63.25516,382
42144.10.64.0/18144.10.64.1 to 144.10.127.254144.10.127.25516,382
43144.10.128.0/18144.10.128.1 to 144.10.191.254144.10.191.25516,382
44144.10.192.0/18144.10.192.1 to 144.10.255.254144.10.255.25516,382
45144.11.0.0/18144.11.0.1 to 144.11.63.254144.11.63.25516,382
46144.11.64.0/18144.11.64.1 to 144.11.127.254144.11.127.25516,382
47144.11.128.0/18144.11.128.1 to 144.11.191.254144.11.191.25516,382
48144.11.192.0/18144.11.192.1 to 144.11.255.254144.11.255.25516,382
49144.12.0.0/18144.12.0.1 to 144.12.63.254144.12.63.25516,382
50144.12.64.0/18144.12.64.1 to 144.12.127.254144.12.127.25516,382
51144.12.128.0/18144.12.128.1 to 144.12.191.254144.12.191.25516,382
52144.12.192.0/18144.12.192.1 to 144.12.255.254144.12.255.25516,382
53144.13.0.0/18144.13.0.1 to 144.13.63.254144.13.63.25516,382
54144.13.64.0/18144.13.64.1 to 144.13.127.254144.13.127.25516,382
55144.13.128.0/18144.13.128.1 to 144.13.191.254144.13.191.25516,382
56144.13.192.0/18144.13.192.1 to 144.13.255.254144.13.255.25516,382
57144.14.0.0/18144.14.0.1 to 144.14.63.254144.14.63.25516,382
58144.14.64.0/18144.14.64.1 to 144.14.127.254144.14.127.25516,382
59144.14.128.0/18144.14.128.1 to 144.14.191.254144.14.191.25516,382
60144.14.192.0/18144.14.192.1 to 144.14.255.254144.14.255.25516,382
61144.15.0.0/18144.15.0.1 to 144.15.63.254144.15.63.25516,382
62144.15.64.0/18144.15.64.1 to 144.15.127.254144.15.127.25516,382
63144.15.128.0/18144.15.128.1 to 144.15.191.254144.15.191.25516,382
64144.15.192.0/18144.15.192.1 to 144.15.255.254144.15.255.25516,382
65144.16.0.0/18144.16.0.1 to 144.16.63.254144.16.63.25516,382
66144.16.64.0/18144.16.64.1 to 144.16.127.254144.16.127.25516,382
67144.16.128.0/18144.16.128.1 to 144.16.191.254144.16.191.25516,382
68144.16.192.0/18144.16.192.1 to 144.16.255.254144.16.255.25516,382
69144.17.0.0/18144.17.0.1 to 144.17.63.254144.17.63.25516,382
70144.17.64.0/18144.17.64.1 to 144.17.127.254144.17.127.25516,382
71144.17.128.0/18144.17.128.1 to 144.17.191.254144.17.191.25516,382
72144.17.192.0/18144.17.192.1 to 144.17.255.254144.17.255.25516,382
73144.18.0.0/18144.18.0.1 to 144.18.63.254144.18.63.25516,382
74144.18.64.0/18144.18.64.1 to 144.18.127.254144.18.127.25516,382
75144.18.128.0/18144.18.128.1 to 144.18.191.254144.18.191.25516,382
76144.18.192.0/18144.18.192.1 to 144.18.255.254144.18.255.25516,382
77144.19.0.0/18144.19.0.1 to 144.19.63.254144.19.63.25516,382
78144.19.64.0/18144.19.64.1 to 144.19.127.254144.19.127.25516,382
79144.19.128.0/18144.19.128.1 to 144.19.191.254144.19.191.25516,382
80144.19.192.0/18144.19.192.1 to 144.19.255.254144.19.255.25516,382
81144.20.0.0/18144.20.0.1 to 144.20.63.254144.20.63.25516,382
82144.20.64.0/18144.20.64.1 to 144.20.127.254144.20.127.25516,382
83144.20.128.0/18144.20.128.1 to 144.20.191.254144.20.191.25516,382
84144.20.192.0/18144.20.192.1 to 144.20.255.254144.20.255.25516,382
85144.21.0.0/18144.21.0.1 to 144.21.63.254144.21.63.25516,382
86144.21.64.0/18144.21.64.1 to 144.21.127.254144.21.127.25516,382
87144.21.128.0/18144.21.128.1 to 144.21.191.254144.21.191.25516,382
88144.21.192.0/18144.21.192.1 to 144.21.255.254144.21.255.25516,382
89144.22.0.0/18144.22.0.1 to 144.22.63.254144.22.63.25516,382
90144.22.64.0/18144.22.64.1 to 144.22.127.254144.22.127.25516,382
91144.22.128.0/18144.22.128.1 to 144.22.191.254144.22.191.25516,382
92144.22.192.0/18144.22.192.1 to 144.22.255.254144.22.255.25516,382
93144.23.0.0/18144.23.0.1 to 144.23.63.254144.23.63.25516,382
94144.23.64.0/18144.23.64.1 to 144.23.127.254144.23.127.25516,382
95144.23.128.0/18144.23.128.1 to 144.23.191.254144.23.191.25516,382
96144.23.192.0/18144.23.192.1 to 144.23.255.254144.23.255.25516,382
97144.24.0.0/18144.24.0.1 to 144.24.63.254144.24.63.25516,382
98144.24.64.0/18144.24.64.1 to 144.24.127.254144.24.127.25516,382
99144.24.128.0/18144.24.128.1 to 144.24.191.254144.24.191.25516,382
100144.24.192.0/18144.24.192.1 to 144.24.255.254144.24.255.25516,382
101144.25.0.0/18144.25.0.1 to 144.25.63.254144.25.63.25516,382
102144.25.64.0/18144.25.64.1 to 144.25.127.254144.25.127.25516,382
103144.25.128.0/18144.25.128.1 to 144.25.191.254144.25.191.25516,382
104144.25.192.0/18144.25.192.1 to 144.25.255.254144.25.255.25516,382
105144.26.0.0/18144.26.0.1 to 144.26.63.254144.26.63.25516,382
106144.26.64.0/18144.26.64.1 to 144.26.127.254144.26.127.25516,382
107144.26.128.0/18144.26.128.1 to 144.26.191.254144.26.191.25516,382
108144.26.192.0/18144.26.192.1 to 144.26.255.254144.26.255.25516,382
109144.27.0.0/18144.27.0.1 to 144.27.63.254144.27.63.25516,382
110144.27.64.0/18144.27.64.1 to 144.27.127.254144.27.127.25516,382
111144.27.128.0/18144.27.128.1 to 144.27.191.254144.27.191.25516,382
112144.27.192.0/18144.27.192.1 to 144.27.255.254144.27.255.25516,382
113144.28.0.0/18144.28.0.1 to 144.28.63.254144.28.63.25516,382
114144.28.64.0/18144.28.64.1 to 144.28.127.254144.28.127.25516,382
115144.28.128.0/18144.28.128.1 to 144.28.191.254144.28.191.25516,382
116144.28.192.0/18144.28.192.1 to 144.28.255.254144.28.255.25516,382
117144.29.0.0/18144.29.0.1 to 144.29.63.254144.29.63.25516,382
118144.29.64.0/18144.29.64.1 to 144.29.127.254144.29.127.25516,382
119144.29.128.0/18144.29.128.1 to 144.29.191.254144.29.191.25516,382
120144.29.192.0/18144.29.192.1 to 144.29.255.254144.29.255.25516,382
121144.30.0.0/18144.30.0.1 to 144.30.63.254144.30.63.25516,382
122144.30.64.0/18144.30.64.1 to 144.30.127.254144.30.127.25516,382
123144.30.128.0/18144.30.128.1 to 144.30.191.254144.30.191.25516,382
124144.30.192.0/18144.30.192.1 to 144.30.255.254144.30.255.25516,382
125144.31.0.0/18144.31.0.1 to 144.31.63.254144.31.63.25516,382
126144.31.64.0/18144.31.64.1 to 144.31.127.254144.31.127.25516,382
127144.31.128.0/18144.31.128.1 to 144.31.191.254144.31.191.25516,382
128144.31.192.0/18144.31.192.1 to 144.31.255.254144.31.255.25516,382
129144.32.0.0/18144.32.0.1 to 144.32.63.254144.32.63.25516,382
130144.32.64.0/18144.32.64.1 to 144.32.127.254144.32.127.25516,382
131144.32.128.0/18144.32.128.1 to 144.32.191.254144.32.191.25516,382
132144.32.192.0/18144.32.192.1 to 144.32.255.254144.32.255.25516,382
133144.33.0.0/18144.33.0.1 to 144.33.63.254144.33.63.25516,382
134144.33.64.0/18144.33.64.1 to 144.33.127.254144.33.127.25516,382
135144.33.128.0/18144.33.128.1 to 144.33.191.254144.33.191.25516,382
136144.33.192.0/18144.33.192.1 to 144.33.255.254144.33.255.25516,382
137144.34.0.0/18144.34.0.1 to 144.34.63.254144.34.63.25516,382
138144.34.64.0/18144.34.64.1 to 144.34.127.254144.34.127.25516,382
139144.34.128.0/18144.34.128.1 to 144.34.191.254144.34.191.25516,382
140144.34.192.0/18144.34.192.1 to 144.34.255.254144.34.255.25516,382
141144.35.0.0/18144.35.0.1 to 144.35.63.254144.35.63.25516,382
142144.35.64.0/18144.35.64.1 to 144.35.127.254144.35.127.25516,382
143144.35.128.0/18144.35.128.1 to 144.35.191.254144.35.191.25516,382
144144.35.192.0/18144.35.192.1 to 144.35.255.254144.35.255.25516,382
145144.36.0.0/18144.36.0.1 to 144.36.63.254144.36.63.25516,382
146144.36.64.0/18144.36.64.1 to 144.36.127.254144.36.127.25516,382
147144.36.128.0/18144.36.128.1 to 144.36.191.254144.36.191.25516,382
148144.36.192.0/18144.36.192.1 to 144.36.255.254144.36.255.25516,382
149144.37.0.0/18144.37.0.1 to 144.37.63.254144.37.63.25516,382
150144.37.64.0/18144.37.64.1 to 144.37.127.254144.37.127.25516,382
151144.37.128.0/18144.37.128.1 to 144.37.191.254144.37.191.25516,382
152144.37.192.0/18144.37.192.1 to 144.37.255.254144.37.255.25516,382
153144.38.0.0/18144.38.0.1 to 144.38.63.254144.38.63.25516,382
154144.38.64.0/18144.38.64.1 to 144.38.127.254144.38.127.25516,382
155144.38.128.0/18144.38.128.1 to 144.38.191.254144.38.191.25516,382
156144.38.192.0/18144.38.192.1 to 144.38.255.254144.38.255.25516,382
157144.39.0.0/18144.39.0.1 to 144.39.63.254144.39.63.25516,382
158144.39.64.0/18144.39.64.1 to 144.39.127.254144.39.127.25516,382
159144.39.128.0/18144.39.128.1 to 144.39.191.254144.39.191.25516,382
160144.39.192.0/18144.39.192.1 to 144.39.255.254144.39.255.25516,382
161144.40.0.0/18144.40.0.1 to 144.40.63.254144.40.63.25516,382
162144.40.64.0/18144.40.64.1 to 144.40.127.254144.40.127.25516,382
163144.40.128.0/18144.40.128.1 to 144.40.191.254144.40.191.25516,382
164144.40.192.0/18144.40.192.1 to 144.40.255.254144.40.255.25516,382
165144.41.0.0/18144.41.0.1 to 144.41.63.254144.41.63.25516,382
166144.41.64.0/18144.41.64.1 to 144.41.127.254144.41.127.25516,382
167144.41.128.0/18144.41.128.1 to 144.41.191.254144.41.191.25516,382
168144.41.192.0/18144.41.192.1 to 144.41.255.254144.41.255.25516,382
169144.42.0.0/18144.42.0.1 to 144.42.63.254144.42.63.25516,382
170144.42.64.0/18144.42.64.1 to 144.42.127.254144.42.127.25516,382
171144.42.128.0/18144.42.128.1 to 144.42.191.254144.42.191.25516,382
172144.42.192.0/18144.42.192.1 to 144.42.255.254144.42.255.25516,382
173144.43.0.0/18144.43.0.1 to 144.43.63.254144.43.63.25516,382
174144.43.64.0/18144.43.64.1 to 144.43.127.254144.43.127.25516,382
175144.43.128.0/18144.43.128.1 to 144.43.191.254144.43.191.25516,382
176144.43.192.0/18144.43.192.1 to 144.43.255.254144.43.255.25516,382
177144.44.0.0/18144.44.0.1 to 144.44.63.254144.44.63.25516,382
178144.44.64.0/18144.44.64.1 to 144.44.127.254144.44.127.25516,382
179144.44.128.0/18144.44.128.1 to 144.44.191.254144.44.191.25516,382
180144.44.192.0/18144.44.192.1 to 144.44.255.254144.44.255.25516,382
181144.45.0.0/18144.45.0.1 to 144.45.63.254144.45.63.25516,382
182144.45.64.0/18144.45.64.1 to 144.45.127.254144.45.127.25516,382
183144.45.128.0/18144.45.128.1 to 144.45.191.254144.45.191.25516,382
184144.45.192.0/18144.45.192.1 to 144.45.255.254144.45.255.25516,382
185144.46.0.0/18144.46.0.1 to 144.46.63.254144.46.63.25516,382
186144.46.64.0/18144.46.64.1 to 144.46.127.254144.46.127.25516,382
187144.46.128.0/18144.46.128.1 to 144.46.191.254144.46.191.25516,382
188144.46.192.0/18144.46.192.1 to 144.46.255.254144.46.255.25516,382
189144.47.0.0/18144.47.0.1 to 144.47.63.254144.47.63.25516,382
190144.47.64.0/18144.47.64.1 to 144.47.127.254144.47.127.25516,382
191144.47.128.0/18144.47.128.1 to 144.47.191.254144.47.191.25516,382
192144.47.192.0/18144.47.192.1 to 144.47.255.254144.47.255.25516,382
193144.48.0.0/18144.48.0.1 to 144.48.63.254144.48.63.25516,382
194144.48.64.0/18144.48.64.1 to 144.48.127.254144.48.127.25516,382
195144.48.128.0/18144.48.128.1 to 144.48.191.254144.48.191.25516,382
196144.48.192.0/18144.48.192.1 to 144.48.255.254144.48.255.25516,382
197144.49.0.0/18144.49.0.1 to 144.49.63.254144.49.63.25516,382
198144.49.64.0/18144.49.64.1 to 144.49.127.254144.49.127.25516,382
199144.49.128.0/18144.49.128.1 to 144.49.191.254144.49.191.25516,382
200144.49.192.0/18144.49.192.1 to 144.49.255.254144.49.255.25516,382
201144.50.0.0/18144.50.0.1 to 144.50.63.254144.50.63.25516,382
202144.50.64.0/18144.50.64.1 to 144.50.127.254144.50.127.25516,382
203144.50.128.0/18144.50.128.1 to 144.50.191.254144.50.191.25516,382
204144.50.192.0/18144.50.192.1 to 144.50.255.254144.50.255.25516,382
205144.51.0.0/18144.51.0.1 to 144.51.63.254144.51.63.25516,382
206144.51.64.0/18144.51.64.1 to 144.51.127.254144.51.127.25516,382
207144.51.128.0/18144.51.128.1 to 144.51.191.254144.51.191.25516,382
208144.51.192.0/18144.51.192.1 to 144.51.255.254144.51.255.25516,382
209144.52.0.0/18144.52.0.1 to 144.52.63.254144.52.63.25516,382
210144.52.64.0/18144.52.64.1 to 144.52.127.254144.52.127.25516,382
211144.52.128.0/18144.52.128.1 to 144.52.191.254144.52.191.25516,382
212144.52.192.0/18144.52.192.1 to 144.52.255.254144.52.255.25516,382
213144.53.0.0/18144.53.0.1 to 144.53.63.254144.53.63.25516,382
214144.53.64.0/18144.53.64.1 to 144.53.127.254144.53.127.25516,382
215144.53.128.0/18144.53.128.1 to 144.53.191.254144.53.191.25516,382
216144.53.192.0/18144.53.192.1 to 144.53.255.254144.53.255.25516,382
217144.54.0.0/18144.54.0.1 to 144.54.63.254144.54.63.25516,382
218144.54.64.0/18144.54.64.1 to 144.54.127.254144.54.127.25516,382
219144.54.128.0/18144.54.128.1 to 144.54.191.254144.54.191.25516,382
220144.54.192.0/18144.54.192.1 to 144.54.255.254144.54.255.25516,382
221144.55.0.0/18144.55.0.1 to 144.55.63.254144.55.63.25516,382
222144.55.64.0/18144.55.64.1 to 144.55.127.254144.55.127.25516,382
223144.55.128.0/18144.55.128.1 to 144.55.191.254144.55.191.25516,382
224144.55.192.0/18144.55.192.1 to 144.55.255.254144.55.255.25516,382
225144.56.0.0/18144.56.0.1 to 144.56.63.254144.56.63.25516,382
226144.56.64.0/18144.56.64.1 to 144.56.127.254144.56.127.25516,382
227144.56.128.0/18144.56.128.1 to 144.56.191.254144.56.191.25516,382
228144.56.192.0/18144.56.192.1 to 144.56.255.254144.56.255.25516,382
229144.57.0.0/18144.57.0.1 to 144.57.63.254144.57.63.25516,382
230144.57.64.0/18144.57.64.1 to 144.57.127.254144.57.127.25516,382
231144.57.128.0/18144.57.128.1 to 144.57.191.254144.57.191.25516,382
232144.57.192.0/18144.57.192.1 to 144.57.255.254144.57.255.25516,382
233144.58.0.0/18144.58.0.1 to 144.58.63.254144.58.63.25516,382
234144.58.64.0/18144.58.64.1 to 144.58.127.254144.58.127.25516,382
235144.58.128.0/18144.58.128.1 to 144.58.191.254144.58.191.25516,382
236144.58.192.0/18144.58.192.1 to 144.58.255.254144.58.255.25516,382
237144.59.0.0/18144.59.0.1 to 144.59.63.254144.59.63.25516,382
238144.59.64.0/18144.59.64.1 to 144.59.127.254144.59.127.25516,382
239144.59.128.0/18144.59.128.1 to 144.59.191.254144.59.191.25516,382
240144.59.192.0/18144.59.192.1 to 144.59.255.254144.59.255.25516,382
241144.60.0.0/18144.60.0.1 to 144.60.63.254144.60.63.25516,382
242144.60.64.0/18144.60.64.1 to 144.60.127.254144.60.127.25516,382
243144.60.128.0/18144.60.128.1 to 144.60.191.254144.60.191.25516,382
244144.60.192.0/18144.60.192.1 to 144.60.255.254144.60.255.25516,382
245144.61.0.0/18144.61.0.1 to 144.61.63.254144.61.63.25516,382
246144.61.64.0/18144.61.64.1 to 144.61.127.254144.61.127.25516,382
247144.61.128.0/18144.61.128.1 to 144.61.191.254144.61.191.25516,382
248144.61.192.0/18144.61.192.1 to 144.61.255.254144.61.255.25516,382
249144.62.0.0/18144.62.0.1 to 144.62.63.254144.62.63.25516,382
250144.62.64.0/18144.62.64.1 to 144.62.127.254144.62.127.25516,382
251144.62.128.0/18144.62.128.1 to 144.62.191.254144.62.191.25516,382
252144.62.192.0/18144.62.192.1 to 144.62.255.254144.62.255.25516,382
253144.63.0.0/18144.63.0.1 to 144.63.63.254144.63.63.25516,382
254144.63.64.0/18144.63.64.1 to 144.63.127.254144.63.127.25516,382
255144.63.128.0/18144.63.128.1 to 144.63.191.254144.63.191.25516,382
256144.63.192.0/18144.63.192.1 to 144.63.255.254144.63.255.25516,382

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.