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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.

Network169.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
169.0.0.0
Broadcast address
169.255.255.255
First usable
169.0.0.1
Last usable
169.255.255.254
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 A9000000 · Integer 2835349504 to 2852126719
Reverse DNS zone
169.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10101001..00000000.00000000.00000000169.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10101001..00000000.00000000.00000000169.0.0.0
Broadcast10101001..11111111.11111111.11111111169.255.255.255
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)

169.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1169.0.0.0/18169.0.0.1 to 169.0.63.254169.0.63.25516,382
2169.0.64.0/18169.0.64.1 to 169.0.127.254169.0.127.25516,382
3169.0.128.0/18169.0.128.1 to 169.0.191.254169.0.191.25516,382
4169.0.192.0/18169.0.192.1 to 169.0.255.254169.0.255.25516,382
5169.1.0.0/18169.1.0.1 to 169.1.63.254169.1.63.25516,382
6169.1.64.0/18169.1.64.1 to 169.1.127.254169.1.127.25516,382
7169.1.128.0/18169.1.128.1 to 169.1.191.254169.1.191.25516,382
8169.1.192.0/18169.1.192.1 to 169.1.255.254169.1.255.25516,382
9169.2.0.0/18169.2.0.1 to 169.2.63.254169.2.63.25516,382
10169.2.64.0/18169.2.64.1 to 169.2.127.254169.2.127.25516,382
11169.2.128.0/18169.2.128.1 to 169.2.191.254169.2.191.25516,382
12169.2.192.0/18169.2.192.1 to 169.2.255.254169.2.255.25516,382
13169.3.0.0/18169.3.0.1 to 169.3.63.254169.3.63.25516,382
14169.3.64.0/18169.3.64.1 to 169.3.127.254169.3.127.25516,382
15169.3.128.0/18169.3.128.1 to 169.3.191.254169.3.191.25516,382
16169.3.192.0/18169.3.192.1 to 169.3.255.254169.3.255.25516,382
17169.4.0.0/18169.4.0.1 to 169.4.63.254169.4.63.25516,382
18169.4.64.0/18169.4.64.1 to 169.4.127.254169.4.127.25516,382
19169.4.128.0/18169.4.128.1 to 169.4.191.254169.4.191.25516,382
20169.4.192.0/18169.4.192.1 to 169.4.255.254169.4.255.25516,382
21169.5.0.0/18169.5.0.1 to 169.5.63.254169.5.63.25516,382
22169.5.64.0/18169.5.64.1 to 169.5.127.254169.5.127.25516,382
23169.5.128.0/18169.5.128.1 to 169.5.191.254169.5.191.25516,382
24169.5.192.0/18169.5.192.1 to 169.5.255.254169.5.255.25516,382
25169.6.0.0/18169.6.0.1 to 169.6.63.254169.6.63.25516,382
26169.6.64.0/18169.6.64.1 to 169.6.127.254169.6.127.25516,382
27169.6.128.0/18169.6.128.1 to 169.6.191.254169.6.191.25516,382
28169.6.192.0/18169.6.192.1 to 169.6.255.254169.6.255.25516,382
29169.7.0.0/18169.7.0.1 to 169.7.63.254169.7.63.25516,382
30169.7.64.0/18169.7.64.1 to 169.7.127.254169.7.127.25516,382
31169.7.128.0/18169.7.128.1 to 169.7.191.254169.7.191.25516,382
32169.7.192.0/18169.7.192.1 to 169.7.255.254169.7.255.25516,382
33169.8.0.0/18169.8.0.1 to 169.8.63.254169.8.63.25516,382
34169.8.64.0/18169.8.64.1 to 169.8.127.254169.8.127.25516,382
35169.8.128.0/18169.8.128.1 to 169.8.191.254169.8.191.25516,382
36169.8.192.0/18169.8.192.1 to 169.8.255.254169.8.255.25516,382
37169.9.0.0/18169.9.0.1 to 169.9.63.254169.9.63.25516,382
38169.9.64.0/18169.9.64.1 to 169.9.127.254169.9.127.25516,382
39169.9.128.0/18169.9.128.1 to 169.9.191.254169.9.191.25516,382
40169.9.192.0/18169.9.192.1 to 169.9.255.254169.9.255.25516,382
41169.10.0.0/18169.10.0.1 to 169.10.63.254169.10.63.25516,382
42169.10.64.0/18169.10.64.1 to 169.10.127.254169.10.127.25516,382
43169.10.128.0/18169.10.128.1 to 169.10.191.254169.10.191.25516,382
44169.10.192.0/18169.10.192.1 to 169.10.255.254169.10.255.25516,382
45169.11.0.0/18169.11.0.1 to 169.11.63.254169.11.63.25516,382
46169.11.64.0/18169.11.64.1 to 169.11.127.254169.11.127.25516,382
47169.11.128.0/18169.11.128.1 to 169.11.191.254169.11.191.25516,382
48169.11.192.0/18169.11.192.1 to 169.11.255.254169.11.255.25516,382
49169.12.0.0/18169.12.0.1 to 169.12.63.254169.12.63.25516,382
50169.12.64.0/18169.12.64.1 to 169.12.127.254169.12.127.25516,382
51169.12.128.0/18169.12.128.1 to 169.12.191.254169.12.191.25516,382
52169.12.192.0/18169.12.192.1 to 169.12.255.254169.12.255.25516,382
53169.13.0.0/18169.13.0.1 to 169.13.63.254169.13.63.25516,382
54169.13.64.0/18169.13.64.1 to 169.13.127.254169.13.127.25516,382
55169.13.128.0/18169.13.128.1 to 169.13.191.254169.13.191.25516,382
56169.13.192.0/18169.13.192.1 to 169.13.255.254169.13.255.25516,382
57169.14.0.0/18169.14.0.1 to 169.14.63.254169.14.63.25516,382
58169.14.64.0/18169.14.64.1 to 169.14.127.254169.14.127.25516,382
59169.14.128.0/18169.14.128.1 to 169.14.191.254169.14.191.25516,382
60169.14.192.0/18169.14.192.1 to 169.14.255.254169.14.255.25516,382
61169.15.0.0/18169.15.0.1 to 169.15.63.254169.15.63.25516,382
62169.15.64.0/18169.15.64.1 to 169.15.127.254169.15.127.25516,382
63169.15.128.0/18169.15.128.1 to 169.15.191.254169.15.191.25516,382
64169.15.192.0/18169.15.192.1 to 169.15.255.254169.15.255.25516,382
65169.16.0.0/18169.16.0.1 to 169.16.63.254169.16.63.25516,382
66169.16.64.0/18169.16.64.1 to 169.16.127.254169.16.127.25516,382
67169.16.128.0/18169.16.128.1 to 169.16.191.254169.16.191.25516,382
68169.16.192.0/18169.16.192.1 to 169.16.255.254169.16.255.25516,382
69169.17.0.0/18169.17.0.1 to 169.17.63.254169.17.63.25516,382
70169.17.64.0/18169.17.64.1 to 169.17.127.254169.17.127.25516,382
71169.17.128.0/18169.17.128.1 to 169.17.191.254169.17.191.25516,382
72169.17.192.0/18169.17.192.1 to 169.17.255.254169.17.255.25516,382
73169.18.0.0/18169.18.0.1 to 169.18.63.254169.18.63.25516,382
74169.18.64.0/18169.18.64.1 to 169.18.127.254169.18.127.25516,382
75169.18.128.0/18169.18.128.1 to 169.18.191.254169.18.191.25516,382
76169.18.192.0/18169.18.192.1 to 169.18.255.254169.18.255.25516,382
77169.19.0.0/18169.19.0.1 to 169.19.63.254169.19.63.25516,382
78169.19.64.0/18169.19.64.1 to 169.19.127.254169.19.127.25516,382
79169.19.128.0/18169.19.128.1 to 169.19.191.254169.19.191.25516,382
80169.19.192.0/18169.19.192.1 to 169.19.255.254169.19.255.25516,382
81169.20.0.0/18169.20.0.1 to 169.20.63.254169.20.63.25516,382
82169.20.64.0/18169.20.64.1 to 169.20.127.254169.20.127.25516,382
83169.20.128.0/18169.20.128.1 to 169.20.191.254169.20.191.25516,382
84169.20.192.0/18169.20.192.1 to 169.20.255.254169.20.255.25516,382
85169.21.0.0/18169.21.0.1 to 169.21.63.254169.21.63.25516,382
86169.21.64.0/18169.21.64.1 to 169.21.127.254169.21.127.25516,382
87169.21.128.0/18169.21.128.1 to 169.21.191.254169.21.191.25516,382
88169.21.192.0/18169.21.192.1 to 169.21.255.254169.21.255.25516,382
89169.22.0.0/18169.22.0.1 to 169.22.63.254169.22.63.25516,382
90169.22.64.0/18169.22.64.1 to 169.22.127.254169.22.127.25516,382
91169.22.128.0/18169.22.128.1 to 169.22.191.254169.22.191.25516,382
92169.22.192.0/18169.22.192.1 to 169.22.255.254169.22.255.25516,382
93169.23.0.0/18169.23.0.1 to 169.23.63.254169.23.63.25516,382
94169.23.64.0/18169.23.64.1 to 169.23.127.254169.23.127.25516,382
95169.23.128.0/18169.23.128.1 to 169.23.191.254169.23.191.25516,382
96169.23.192.0/18169.23.192.1 to 169.23.255.254169.23.255.25516,382
97169.24.0.0/18169.24.0.1 to 169.24.63.254169.24.63.25516,382
98169.24.64.0/18169.24.64.1 to 169.24.127.254169.24.127.25516,382
99169.24.128.0/18169.24.128.1 to 169.24.191.254169.24.191.25516,382
100169.24.192.0/18169.24.192.1 to 169.24.255.254169.24.255.25516,382
101169.25.0.0/18169.25.0.1 to 169.25.63.254169.25.63.25516,382
102169.25.64.0/18169.25.64.1 to 169.25.127.254169.25.127.25516,382
103169.25.128.0/18169.25.128.1 to 169.25.191.254169.25.191.25516,382
104169.25.192.0/18169.25.192.1 to 169.25.255.254169.25.255.25516,382
105169.26.0.0/18169.26.0.1 to 169.26.63.254169.26.63.25516,382
106169.26.64.0/18169.26.64.1 to 169.26.127.254169.26.127.25516,382
107169.26.128.0/18169.26.128.1 to 169.26.191.254169.26.191.25516,382
108169.26.192.0/18169.26.192.1 to 169.26.255.254169.26.255.25516,382
109169.27.0.0/18169.27.0.1 to 169.27.63.254169.27.63.25516,382
110169.27.64.0/18169.27.64.1 to 169.27.127.254169.27.127.25516,382
111169.27.128.0/18169.27.128.1 to 169.27.191.254169.27.191.25516,382
112169.27.192.0/18169.27.192.1 to 169.27.255.254169.27.255.25516,382
113169.28.0.0/18169.28.0.1 to 169.28.63.254169.28.63.25516,382
114169.28.64.0/18169.28.64.1 to 169.28.127.254169.28.127.25516,382
115169.28.128.0/18169.28.128.1 to 169.28.191.254169.28.191.25516,382
116169.28.192.0/18169.28.192.1 to 169.28.255.254169.28.255.25516,382
117169.29.0.0/18169.29.0.1 to 169.29.63.254169.29.63.25516,382
118169.29.64.0/18169.29.64.1 to 169.29.127.254169.29.127.25516,382
119169.29.128.0/18169.29.128.1 to 169.29.191.254169.29.191.25516,382
120169.29.192.0/18169.29.192.1 to 169.29.255.254169.29.255.25516,382
121169.30.0.0/18169.30.0.1 to 169.30.63.254169.30.63.25516,382
122169.30.64.0/18169.30.64.1 to 169.30.127.254169.30.127.25516,382
123169.30.128.0/18169.30.128.1 to 169.30.191.254169.30.191.25516,382
124169.30.192.0/18169.30.192.1 to 169.30.255.254169.30.255.25516,382
125169.31.0.0/18169.31.0.1 to 169.31.63.254169.31.63.25516,382
126169.31.64.0/18169.31.64.1 to 169.31.127.254169.31.127.25516,382
127169.31.128.0/18169.31.128.1 to 169.31.191.254169.31.191.25516,382
128169.31.192.0/18169.31.192.1 to 169.31.255.254169.31.255.25516,382
129169.32.0.0/18169.32.0.1 to 169.32.63.254169.32.63.25516,382
130169.32.64.0/18169.32.64.1 to 169.32.127.254169.32.127.25516,382
131169.32.128.0/18169.32.128.1 to 169.32.191.254169.32.191.25516,382
132169.32.192.0/18169.32.192.1 to 169.32.255.254169.32.255.25516,382
133169.33.0.0/18169.33.0.1 to 169.33.63.254169.33.63.25516,382
134169.33.64.0/18169.33.64.1 to 169.33.127.254169.33.127.25516,382
135169.33.128.0/18169.33.128.1 to 169.33.191.254169.33.191.25516,382
136169.33.192.0/18169.33.192.1 to 169.33.255.254169.33.255.25516,382
137169.34.0.0/18169.34.0.1 to 169.34.63.254169.34.63.25516,382
138169.34.64.0/18169.34.64.1 to 169.34.127.254169.34.127.25516,382
139169.34.128.0/18169.34.128.1 to 169.34.191.254169.34.191.25516,382
140169.34.192.0/18169.34.192.1 to 169.34.255.254169.34.255.25516,382
141169.35.0.0/18169.35.0.1 to 169.35.63.254169.35.63.25516,382
142169.35.64.0/18169.35.64.1 to 169.35.127.254169.35.127.25516,382
143169.35.128.0/18169.35.128.1 to 169.35.191.254169.35.191.25516,382
144169.35.192.0/18169.35.192.1 to 169.35.255.254169.35.255.25516,382
145169.36.0.0/18169.36.0.1 to 169.36.63.254169.36.63.25516,382
146169.36.64.0/18169.36.64.1 to 169.36.127.254169.36.127.25516,382
147169.36.128.0/18169.36.128.1 to 169.36.191.254169.36.191.25516,382
148169.36.192.0/18169.36.192.1 to 169.36.255.254169.36.255.25516,382
149169.37.0.0/18169.37.0.1 to 169.37.63.254169.37.63.25516,382
150169.37.64.0/18169.37.64.1 to 169.37.127.254169.37.127.25516,382
151169.37.128.0/18169.37.128.1 to 169.37.191.254169.37.191.25516,382
152169.37.192.0/18169.37.192.1 to 169.37.255.254169.37.255.25516,382
153169.38.0.0/18169.38.0.1 to 169.38.63.254169.38.63.25516,382
154169.38.64.0/18169.38.64.1 to 169.38.127.254169.38.127.25516,382
155169.38.128.0/18169.38.128.1 to 169.38.191.254169.38.191.25516,382
156169.38.192.0/18169.38.192.1 to 169.38.255.254169.38.255.25516,382
157169.39.0.0/18169.39.0.1 to 169.39.63.254169.39.63.25516,382
158169.39.64.0/18169.39.64.1 to 169.39.127.254169.39.127.25516,382
159169.39.128.0/18169.39.128.1 to 169.39.191.254169.39.191.25516,382
160169.39.192.0/18169.39.192.1 to 169.39.255.254169.39.255.25516,382
161169.40.0.0/18169.40.0.1 to 169.40.63.254169.40.63.25516,382
162169.40.64.0/18169.40.64.1 to 169.40.127.254169.40.127.25516,382
163169.40.128.0/18169.40.128.1 to 169.40.191.254169.40.191.25516,382
164169.40.192.0/18169.40.192.1 to 169.40.255.254169.40.255.25516,382
165169.41.0.0/18169.41.0.1 to 169.41.63.254169.41.63.25516,382
166169.41.64.0/18169.41.64.1 to 169.41.127.254169.41.127.25516,382
167169.41.128.0/18169.41.128.1 to 169.41.191.254169.41.191.25516,382
168169.41.192.0/18169.41.192.1 to 169.41.255.254169.41.255.25516,382
169169.42.0.0/18169.42.0.1 to 169.42.63.254169.42.63.25516,382
170169.42.64.0/18169.42.64.1 to 169.42.127.254169.42.127.25516,382
171169.42.128.0/18169.42.128.1 to 169.42.191.254169.42.191.25516,382
172169.42.192.0/18169.42.192.1 to 169.42.255.254169.42.255.25516,382
173169.43.0.0/18169.43.0.1 to 169.43.63.254169.43.63.25516,382
174169.43.64.0/18169.43.64.1 to 169.43.127.254169.43.127.25516,382
175169.43.128.0/18169.43.128.1 to 169.43.191.254169.43.191.25516,382
176169.43.192.0/18169.43.192.1 to 169.43.255.254169.43.255.25516,382
177169.44.0.0/18169.44.0.1 to 169.44.63.254169.44.63.25516,382
178169.44.64.0/18169.44.64.1 to 169.44.127.254169.44.127.25516,382
179169.44.128.0/18169.44.128.1 to 169.44.191.254169.44.191.25516,382
180169.44.192.0/18169.44.192.1 to 169.44.255.254169.44.255.25516,382
181169.45.0.0/18169.45.0.1 to 169.45.63.254169.45.63.25516,382
182169.45.64.0/18169.45.64.1 to 169.45.127.254169.45.127.25516,382
183169.45.128.0/18169.45.128.1 to 169.45.191.254169.45.191.25516,382
184169.45.192.0/18169.45.192.1 to 169.45.255.254169.45.255.25516,382
185169.46.0.0/18169.46.0.1 to 169.46.63.254169.46.63.25516,382
186169.46.64.0/18169.46.64.1 to 169.46.127.254169.46.127.25516,382
187169.46.128.0/18169.46.128.1 to 169.46.191.254169.46.191.25516,382
188169.46.192.0/18169.46.192.1 to 169.46.255.254169.46.255.25516,382
189169.47.0.0/18169.47.0.1 to 169.47.63.254169.47.63.25516,382
190169.47.64.0/18169.47.64.1 to 169.47.127.254169.47.127.25516,382
191169.47.128.0/18169.47.128.1 to 169.47.191.254169.47.191.25516,382
192169.47.192.0/18169.47.192.1 to 169.47.255.254169.47.255.25516,382
193169.48.0.0/18169.48.0.1 to 169.48.63.254169.48.63.25516,382
194169.48.64.0/18169.48.64.1 to 169.48.127.254169.48.127.25516,382
195169.48.128.0/18169.48.128.1 to 169.48.191.254169.48.191.25516,382
196169.48.192.0/18169.48.192.1 to 169.48.255.254169.48.255.25516,382
197169.49.0.0/18169.49.0.1 to 169.49.63.254169.49.63.25516,382
198169.49.64.0/18169.49.64.1 to 169.49.127.254169.49.127.25516,382
199169.49.128.0/18169.49.128.1 to 169.49.191.254169.49.191.25516,382
200169.49.192.0/18169.49.192.1 to 169.49.255.254169.49.255.25516,382
201169.50.0.0/18169.50.0.1 to 169.50.63.254169.50.63.25516,382
202169.50.64.0/18169.50.64.1 to 169.50.127.254169.50.127.25516,382
203169.50.128.0/18169.50.128.1 to 169.50.191.254169.50.191.25516,382
204169.50.192.0/18169.50.192.1 to 169.50.255.254169.50.255.25516,382
205169.51.0.0/18169.51.0.1 to 169.51.63.254169.51.63.25516,382
206169.51.64.0/18169.51.64.1 to 169.51.127.254169.51.127.25516,382
207169.51.128.0/18169.51.128.1 to 169.51.191.254169.51.191.25516,382
208169.51.192.0/18169.51.192.1 to 169.51.255.254169.51.255.25516,382
209169.52.0.0/18169.52.0.1 to 169.52.63.254169.52.63.25516,382
210169.52.64.0/18169.52.64.1 to 169.52.127.254169.52.127.25516,382
211169.52.128.0/18169.52.128.1 to 169.52.191.254169.52.191.25516,382
212169.52.192.0/18169.52.192.1 to 169.52.255.254169.52.255.25516,382
213169.53.0.0/18169.53.0.1 to 169.53.63.254169.53.63.25516,382
214169.53.64.0/18169.53.64.1 to 169.53.127.254169.53.127.25516,382
215169.53.128.0/18169.53.128.1 to 169.53.191.254169.53.191.25516,382
216169.53.192.0/18169.53.192.1 to 169.53.255.254169.53.255.25516,382
217169.54.0.0/18169.54.0.1 to 169.54.63.254169.54.63.25516,382
218169.54.64.0/18169.54.64.1 to 169.54.127.254169.54.127.25516,382
219169.54.128.0/18169.54.128.1 to 169.54.191.254169.54.191.25516,382
220169.54.192.0/18169.54.192.1 to 169.54.255.254169.54.255.25516,382
221169.55.0.0/18169.55.0.1 to 169.55.63.254169.55.63.25516,382
222169.55.64.0/18169.55.64.1 to 169.55.127.254169.55.127.25516,382
223169.55.128.0/18169.55.128.1 to 169.55.191.254169.55.191.25516,382
224169.55.192.0/18169.55.192.1 to 169.55.255.254169.55.255.25516,382
225169.56.0.0/18169.56.0.1 to 169.56.63.254169.56.63.25516,382
226169.56.64.0/18169.56.64.1 to 169.56.127.254169.56.127.25516,382
227169.56.128.0/18169.56.128.1 to 169.56.191.254169.56.191.25516,382
228169.56.192.0/18169.56.192.1 to 169.56.255.254169.56.255.25516,382
229169.57.0.0/18169.57.0.1 to 169.57.63.254169.57.63.25516,382
230169.57.64.0/18169.57.64.1 to 169.57.127.254169.57.127.25516,382
231169.57.128.0/18169.57.128.1 to 169.57.191.254169.57.191.25516,382
232169.57.192.0/18169.57.192.1 to 169.57.255.254169.57.255.25516,382
233169.58.0.0/18169.58.0.1 to 169.58.63.254169.58.63.25516,382
234169.58.64.0/18169.58.64.1 to 169.58.127.254169.58.127.25516,382
235169.58.128.0/18169.58.128.1 to 169.58.191.254169.58.191.25516,382
236169.58.192.0/18169.58.192.1 to 169.58.255.254169.58.255.25516,382
237169.59.0.0/18169.59.0.1 to 169.59.63.254169.59.63.25516,382
238169.59.64.0/18169.59.64.1 to 169.59.127.254169.59.127.25516,382
239169.59.128.0/18169.59.128.1 to 169.59.191.254169.59.191.25516,382
240169.59.192.0/18169.59.192.1 to 169.59.255.254169.59.255.25516,382
241169.60.0.0/18169.60.0.1 to 169.60.63.254169.60.63.25516,382
242169.60.64.0/18169.60.64.1 to 169.60.127.254169.60.127.25516,382
243169.60.128.0/18169.60.128.1 to 169.60.191.254169.60.191.25516,382
244169.60.192.0/18169.60.192.1 to 169.60.255.254169.60.255.25516,382
245169.61.0.0/18169.61.0.1 to 169.61.63.254169.61.63.25516,382
246169.61.64.0/18169.61.64.1 to 169.61.127.254169.61.127.25516,382
247169.61.128.0/18169.61.128.1 to 169.61.191.254169.61.191.25516,382
248169.61.192.0/18169.61.192.1 to 169.61.255.254169.61.255.25516,382
249169.62.0.0/18169.62.0.1 to 169.62.63.254169.62.63.25516,382
250169.62.64.0/18169.62.64.1 to 169.62.127.254169.62.127.25516,382
251169.62.128.0/18169.62.128.1 to 169.62.191.254169.62.191.25516,382
252169.62.192.0/18169.62.192.1 to 169.62.255.254169.62.255.25516,382
253169.63.0.0/18169.63.0.1 to 169.63.63.254169.63.63.25516,382
254169.63.64.0/18169.63.64.1 to 169.63.127.254169.63.127.25516,382
255169.63.128.0/18169.63.128.1 to 169.63.191.254169.63.191.25516,382
256169.63.192.0/18169.63.192.1 to 169.63.255.254169.63.255.25516,382

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.