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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/20
/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 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1169.0.0.0/20169.0.0.1 to 169.0.15.254169.0.15.2554,094
2169.0.16.0/20169.0.16.1 to 169.0.31.254169.0.31.2554,094
3169.0.32.0/20169.0.32.1 to 169.0.47.254169.0.47.2554,094
4169.0.48.0/20169.0.48.1 to 169.0.63.254169.0.63.2554,094
5169.0.64.0/20169.0.64.1 to 169.0.79.254169.0.79.2554,094
6169.0.80.0/20169.0.80.1 to 169.0.95.254169.0.95.2554,094
7169.0.96.0/20169.0.96.1 to 169.0.111.254169.0.111.2554,094
8169.0.112.0/20169.0.112.1 to 169.0.127.254169.0.127.2554,094
9169.0.128.0/20169.0.128.1 to 169.0.143.254169.0.143.2554,094
10169.0.144.0/20169.0.144.1 to 169.0.159.254169.0.159.2554,094
11169.0.160.0/20169.0.160.1 to 169.0.175.254169.0.175.2554,094
12169.0.176.0/20169.0.176.1 to 169.0.191.254169.0.191.2554,094
13169.0.192.0/20169.0.192.1 to 169.0.207.254169.0.207.2554,094
14169.0.208.0/20169.0.208.1 to 169.0.223.254169.0.223.2554,094
15169.0.224.0/20169.0.224.1 to 169.0.239.254169.0.239.2554,094
16169.0.240.0/20169.0.240.1 to 169.0.255.254169.0.255.2554,094
17169.1.0.0/20169.1.0.1 to 169.1.15.254169.1.15.2554,094
18169.1.16.0/20169.1.16.1 to 169.1.31.254169.1.31.2554,094
19169.1.32.0/20169.1.32.1 to 169.1.47.254169.1.47.2554,094
20169.1.48.0/20169.1.48.1 to 169.1.63.254169.1.63.2554,094
21169.1.64.0/20169.1.64.1 to 169.1.79.254169.1.79.2554,094
22169.1.80.0/20169.1.80.1 to 169.1.95.254169.1.95.2554,094
23169.1.96.0/20169.1.96.1 to 169.1.111.254169.1.111.2554,094
24169.1.112.0/20169.1.112.1 to 169.1.127.254169.1.127.2554,094
25169.1.128.0/20169.1.128.1 to 169.1.143.254169.1.143.2554,094
26169.1.144.0/20169.1.144.1 to 169.1.159.254169.1.159.2554,094
27169.1.160.0/20169.1.160.1 to 169.1.175.254169.1.175.2554,094
28169.1.176.0/20169.1.176.1 to 169.1.191.254169.1.191.2554,094
29169.1.192.0/20169.1.192.1 to 169.1.207.254169.1.207.2554,094
30169.1.208.0/20169.1.208.1 to 169.1.223.254169.1.223.2554,094
31169.1.224.0/20169.1.224.1 to 169.1.239.254169.1.239.2554,094
32169.1.240.0/20169.1.240.1 to 169.1.255.254169.1.255.2554,094
33169.2.0.0/20169.2.0.1 to 169.2.15.254169.2.15.2554,094
34169.2.16.0/20169.2.16.1 to 169.2.31.254169.2.31.2554,094
35169.2.32.0/20169.2.32.1 to 169.2.47.254169.2.47.2554,094
36169.2.48.0/20169.2.48.1 to 169.2.63.254169.2.63.2554,094
37169.2.64.0/20169.2.64.1 to 169.2.79.254169.2.79.2554,094
38169.2.80.0/20169.2.80.1 to 169.2.95.254169.2.95.2554,094
39169.2.96.0/20169.2.96.1 to 169.2.111.254169.2.111.2554,094
40169.2.112.0/20169.2.112.1 to 169.2.127.254169.2.127.2554,094
41169.2.128.0/20169.2.128.1 to 169.2.143.254169.2.143.2554,094
42169.2.144.0/20169.2.144.1 to 169.2.159.254169.2.159.2554,094
43169.2.160.0/20169.2.160.1 to 169.2.175.254169.2.175.2554,094
44169.2.176.0/20169.2.176.1 to 169.2.191.254169.2.191.2554,094
45169.2.192.0/20169.2.192.1 to 169.2.207.254169.2.207.2554,094
46169.2.208.0/20169.2.208.1 to 169.2.223.254169.2.223.2554,094
47169.2.224.0/20169.2.224.1 to 169.2.239.254169.2.239.2554,094
48169.2.240.0/20169.2.240.1 to 169.2.255.254169.2.255.2554,094
49169.3.0.0/20169.3.0.1 to 169.3.15.254169.3.15.2554,094
50169.3.16.0/20169.3.16.1 to 169.3.31.254169.3.31.2554,094
51169.3.32.0/20169.3.32.1 to 169.3.47.254169.3.47.2554,094
52169.3.48.0/20169.3.48.1 to 169.3.63.254169.3.63.2554,094
53169.3.64.0/20169.3.64.1 to 169.3.79.254169.3.79.2554,094
54169.3.80.0/20169.3.80.1 to 169.3.95.254169.3.95.2554,094
55169.3.96.0/20169.3.96.1 to 169.3.111.254169.3.111.2554,094
56169.3.112.0/20169.3.112.1 to 169.3.127.254169.3.127.2554,094
57169.3.128.0/20169.3.128.1 to 169.3.143.254169.3.143.2554,094
58169.3.144.0/20169.3.144.1 to 169.3.159.254169.3.159.2554,094
59169.3.160.0/20169.3.160.1 to 169.3.175.254169.3.175.2554,094
60169.3.176.0/20169.3.176.1 to 169.3.191.254169.3.191.2554,094
61169.3.192.0/20169.3.192.1 to 169.3.207.254169.3.207.2554,094
62169.3.208.0/20169.3.208.1 to 169.3.223.254169.3.223.2554,094
63169.3.224.0/20169.3.224.1 to 169.3.239.254169.3.239.2554,094
64169.3.240.0/20169.3.240.1 to 169.3.255.254169.3.255.2554,094
65169.4.0.0/20169.4.0.1 to 169.4.15.254169.4.15.2554,094
66169.4.16.0/20169.4.16.1 to 169.4.31.254169.4.31.2554,094
67169.4.32.0/20169.4.32.1 to 169.4.47.254169.4.47.2554,094
68169.4.48.0/20169.4.48.1 to 169.4.63.254169.4.63.2554,094
69169.4.64.0/20169.4.64.1 to 169.4.79.254169.4.79.2554,094
70169.4.80.0/20169.4.80.1 to 169.4.95.254169.4.95.2554,094
71169.4.96.0/20169.4.96.1 to 169.4.111.254169.4.111.2554,094
72169.4.112.0/20169.4.112.1 to 169.4.127.254169.4.127.2554,094
73169.4.128.0/20169.4.128.1 to 169.4.143.254169.4.143.2554,094
74169.4.144.0/20169.4.144.1 to 169.4.159.254169.4.159.2554,094
75169.4.160.0/20169.4.160.1 to 169.4.175.254169.4.175.2554,094
76169.4.176.0/20169.4.176.1 to 169.4.191.254169.4.191.2554,094
77169.4.192.0/20169.4.192.1 to 169.4.207.254169.4.207.2554,094
78169.4.208.0/20169.4.208.1 to 169.4.223.254169.4.223.2554,094
79169.4.224.0/20169.4.224.1 to 169.4.239.254169.4.239.2554,094
80169.4.240.0/20169.4.240.1 to 169.4.255.254169.4.255.2554,094
81169.5.0.0/20169.5.0.1 to 169.5.15.254169.5.15.2554,094
82169.5.16.0/20169.5.16.1 to 169.5.31.254169.5.31.2554,094
83169.5.32.0/20169.5.32.1 to 169.5.47.254169.5.47.2554,094
84169.5.48.0/20169.5.48.1 to 169.5.63.254169.5.63.2554,094
85169.5.64.0/20169.5.64.1 to 169.5.79.254169.5.79.2554,094
86169.5.80.0/20169.5.80.1 to 169.5.95.254169.5.95.2554,094
87169.5.96.0/20169.5.96.1 to 169.5.111.254169.5.111.2554,094
88169.5.112.0/20169.5.112.1 to 169.5.127.254169.5.127.2554,094
89169.5.128.0/20169.5.128.1 to 169.5.143.254169.5.143.2554,094
90169.5.144.0/20169.5.144.1 to 169.5.159.254169.5.159.2554,094
91169.5.160.0/20169.5.160.1 to 169.5.175.254169.5.175.2554,094
92169.5.176.0/20169.5.176.1 to 169.5.191.254169.5.191.2554,094
93169.5.192.0/20169.5.192.1 to 169.5.207.254169.5.207.2554,094
94169.5.208.0/20169.5.208.1 to 169.5.223.254169.5.223.2554,094
95169.5.224.0/20169.5.224.1 to 169.5.239.254169.5.239.2554,094
96169.5.240.0/20169.5.240.1 to 169.5.255.254169.5.255.2554,094
97169.6.0.0/20169.6.0.1 to 169.6.15.254169.6.15.2554,094
98169.6.16.0/20169.6.16.1 to 169.6.31.254169.6.31.2554,094
99169.6.32.0/20169.6.32.1 to 169.6.47.254169.6.47.2554,094
100169.6.48.0/20169.6.48.1 to 169.6.63.254169.6.63.2554,094
101169.6.64.0/20169.6.64.1 to 169.6.79.254169.6.79.2554,094
102169.6.80.0/20169.6.80.1 to 169.6.95.254169.6.95.2554,094
103169.6.96.0/20169.6.96.1 to 169.6.111.254169.6.111.2554,094
104169.6.112.0/20169.6.112.1 to 169.6.127.254169.6.127.2554,094
105169.6.128.0/20169.6.128.1 to 169.6.143.254169.6.143.2554,094
106169.6.144.0/20169.6.144.1 to 169.6.159.254169.6.159.2554,094
107169.6.160.0/20169.6.160.1 to 169.6.175.254169.6.175.2554,094
108169.6.176.0/20169.6.176.1 to 169.6.191.254169.6.191.2554,094
109169.6.192.0/20169.6.192.1 to 169.6.207.254169.6.207.2554,094
110169.6.208.0/20169.6.208.1 to 169.6.223.254169.6.223.2554,094
111169.6.224.0/20169.6.224.1 to 169.6.239.254169.6.239.2554,094
112169.6.240.0/20169.6.240.1 to 169.6.255.254169.6.255.2554,094
113169.7.0.0/20169.7.0.1 to 169.7.15.254169.7.15.2554,094
114169.7.16.0/20169.7.16.1 to 169.7.31.254169.7.31.2554,094
115169.7.32.0/20169.7.32.1 to 169.7.47.254169.7.47.2554,094
116169.7.48.0/20169.7.48.1 to 169.7.63.254169.7.63.2554,094
117169.7.64.0/20169.7.64.1 to 169.7.79.254169.7.79.2554,094
118169.7.80.0/20169.7.80.1 to 169.7.95.254169.7.95.2554,094
119169.7.96.0/20169.7.96.1 to 169.7.111.254169.7.111.2554,094
120169.7.112.0/20169.7.112.1 to 169.7.127.254169.7.127.2554,094
121169.7.128.0/20169.7.128.1 to 169.7.143.254169.7.143.2554,094
122169.7.144.0/20169.7.144.1 to 169.7.159.254169.7.159.2554,094
123169.7.160.0/20169.7.160.1 to 169.7.175.254169.7.175.2554,094
124169.7.176.0/20169.7.176.1 to 169.7.191.254169.7.191.2554,094
125169.7.192.0/20169.7.192.1 to 169.7.207.254169.7.207.2554,094
126169.7.208.0/20169.7.208.1 to 169.7.223.254169.7.223.2554,094
127169.7.224.0/20169.7.224.1 to 169.7.239.254169.7.239.2554,094
128169.7.240.0/20169.7.240.1 to 169.7.255.254169.7.255.2554,094
129169.8.0.0/20169.8.0.1 to 169.8.15.254169.8.15.2554,094
130169.8.16.0/20169.8.16.1 to 169.8.31.254169.8.31.2554,094
131169.8.32.0/20169.8.32.1 to 169.8.47.254169.8.47.2554,094
132169.8.48.0/20169.8.48.1 to 169.8.63.254169.8.63.2554,094
133169.8.64.0/20169.8.64.1 to 169.8.79.254169.8.79.2554,094
134169.8.80.0/20169.8.80.1 to 169.8.95.254169.8.95.2554,094
135169.8.96.0/20169.8.96.1 to 169.8.111.254169.8.111.2554,094
136169.8.112.0/20169.8.112.1 to 169.8.127.254169.8.127.2554,094
137169.8.128.0/20169.8.128.1 to 169.8.143.254169.8.143.2554,094
138169.8.144.0/20169.8.144.1 to 169.8.159.254169.8.159.2554,094
139169.8.160.0/20169.8.160.1 to 169.8.175.254169.8.175.2554,094
140169.8.176.0/20169.8.176.1 to 169.8.191.254169.8.191.2554,094
141169.8.192.0/20169.8.192.1 to 169.8.207.254169.8.207.2554,094
142169.8.208.0/20169.8.208.1 to 169.8.223.254169.8.223.2554,094
143169.8.224.0/20169.8.224.1 to 169.8.239.254169.8.239.2554,094
144169.8.240.0/20169.8.240.1 to 169.8.255.254169.8.255.2554,094
145169.9.0.0/20169.9.0.1 to 169.9.15.254169.9.15.2554,094
146169.9.16.0/20169.9.16.1 to 169.9.31.254169.9.31.2554,094
147169.9.32.0/20169.9.32.1 to 169.9.47.254169.9.47.2554,094
148169.9.48.0/20169.9.48.1 to 169.9.63.254169.9.63.2554,094
149169.9.64.0/20169.9.64.1 to 169.9.79.254169.9.79.2554,094
150169.9.80.0/20169.9.80.1 to 169.9.95.254169.9.95.2554,094
151169.9.96.0/20169.9.96.1 to 169.9.111.254169.9.111.2554,094
152169.9.112.0/20169.9.112.1 to 169.9.127.254169.9.127.2554,094
153169.9.128.0/20169.9.128.1 to 169.9.143.254169.9.143.2554,094
154169.9.144.0/20169.9.144.1 to 169.9.159.254169.9.159.2554,094
155169.9.160.0/20169.9.160.1 to 169.9.175.254169.9.175.2554,094
156169.9.176.0/20169.9.176.1 to 169.9.191.254169.9.191.2554,094
157169.9.192.0/20169.9.192.1 to 169.9.207.254169.9.207.2554,094
158169.9.208.0/20169.9.208.1 to 169.9.223.254169.9.223.2554,094
159169.9.224.0/20169.9.224.1 to 169.9.239.254169.9.239.2554,094
160169.9.240.0/20169.9.240.1 to 169.9.255.254169.9.255.2554,094
161169.10.0.0/20169.10.0.1 to 169.10.15.254169.10.15.2554,094
162169.10.16.0/20169.10.16.1 to 169.10.31.254169.10.31.2554,094
163169.10.32.0/20169.10.32.1 to 169.10.47.254169.10.47.2554,094
164169.10.48.0/20169.10.48.1 to 169.10.63.254169.10.63.2554,094
165169.10.64.0/20169.10.64.1 to 169.10.79.254169.10.79.2554,094
166169.10.80.0/20169.10.80.1 to 169.10.95.254169.10.95.2554,094
167169.10.96.0/20169.10.96.1 to 169.10.111.254169.10.111.2554,094
168169.10.112.0/20169.10.112.1 to 169.10.127.254169.10.127.2554,094
169169.10.128.0/20169.10.128.1 to 169.10.143.254169.10.143.2554,094
170169.10.144.0/20169.10.144.1 to 169.10.159.254169.10.159.2554,094
171169.10.160.0/20169.10.160.1 to 169.10.175.254169.10.175.2554,094
172169.10.176.0/20169.10.176.1 to 169.10.191.254169.10.191.2554,094
173169.10.192.0/20169.10.192.1 to 169.10.207.254169.10.207.2554,094
174169.10.208.0/20169.10.208.1 to 169.10.223.254169.10.223.2554,094
175169.10.224.0/20169.10.224.1 to 169.10.239.254169.10.239.2554,094
176169.10.240.0/20169.10.240.1 to 169.10.255.254169.10.255.2554,094
177169.11.0.0/20169.11.0.1 to 169.11.15.254169.11.15.2554,094
178169.11.16.0/20169.11.16.1 to 169.11.31.254169.11.31.2554,094
179169.11.32.0/20169.11.32.1 to 169.11.47.254169.11.47.2554,094
180169.11.48.0/20169.11.48.1 to 169.11.63.254169.11.63.2554,094
181169.11.64.0/20169.11.64.1 to 169.11.79.254169.11.79.2554,094
182169.11.80.0/20169.11.80.1 to 169.11.95.254169.11.95.2554,094
183169.11.96.0/20169.11.96.1 to 169.11.111.254169.11.111.2554,094
184169.11.112.0/20169.11.112.1 to 169.11.127.254169.11.127.2554,094
185169.11.128.0/20169.11.128.1 to 169.11.143.254169.11.143.2554,094
186169.11.144.0/20169.11.144.1 to 169.11.159.254169.11.159.2554,094
187169.11.160.0/20169.11.160.1 to 169.11.175.254169.11.175.2554,094
188169.11.176.0/20169.11.176.1 to 169.11.191.254169.11.191.2554,094
189169.11.192.0/20169.11.192.1 to 169.11.207.254169.11.207.2554,094
190169.11.208.0/20169.11.208.1 to 169.11.223.254169.11.223.2554,094
191169.11.224.0/20169.11.224.1 to 169.11.239.254169.11.239.2554,094
192169.11.240.0/20169.11.240.1 to 169.11.255.254169.11.255.2554,094
193169.12.0.0/20169.12.0.1 to 169.12.15.254169.12.15.2554,094
194169.12.16.0/20169.12.16.1 to 169.12.31.254169.12.31.2554,094
195169.12.32.0/20169.12.32.1 to 169.12.47.254169.12.47.2554,094
196169.12.48.0/20169.12.48.1 to 169.12.63.254169.12.63.2554,094
197169.12.64.0/20169.12.64.1 to 169.12.79.254169.12.79.2554,094
198169.12.80.0/20169.12.80.1 to 169.12.95.254169.12.95.2554,094
199169.12.96.0/20169.12.96.1 to 169.12.111.254169.12.111.2554,094
200169.12.112.0/20169.12.112.1 to 169.12.127.254169.12.127.2554,094
201169.12.128.0/20169.12.128.1 to 169.12.143.254169.12.143.2554,094
202169.12.144.0/20169.12.144.1 to 169.12.159.254169.12.159.2554,094
203169.12.160.0/20169.12.160.1 to 169.12.175.254169.12.175.2554,094
204169.12.176.0/20169.12.176.1 to 169.12.191.254169.12.191.2554,094
205169.12.192.0/20169.12.192.1 to 169.12.207.254169.12.207.2554,094
206169.12.208.0/20169.12.208.1 to 169.12.223.254169.12.223.2554,094
207169.12.224.0/20169.12.224.1 to 169.12.239.254169.12.239.2554,094
208169.12.240.0/20169.12.240.1 to 169.12.255.254169.12.255.2554,094
209169.13.0.0/20169.13.0.1 to 169.13.15.254169.13.15.2554,094
210169.13.16.0/20169.13.16.1 to 169.13.31.254169.13.31.2554,094
211169.13.32.0/20169.13.32.1 to 169.13.47.254169.13.47.2554,094
212169.13.48.0/20169.13.48.1 to 169.13.63.254169.13.63.2554,094
213169.13.64.0/20169.13.64.1 to 169.13.79.254169.13.79.2554,094
214169.13.80.0/20169.13.80.1 to 169.13.95.254169.13.95.2554,094
215169.13.96.0/20169.13.96.1 to 169.13.111.254169.13.111.2554,094
216169.13.112.0/20169.13.112.1 to 169.13.127.254169.13.127.2554,094
217169.13.128.0/20169.13.128.1 to 169.13.143.254169.13.143.2554,094
218169.13.144.0/20169.13.144.1 to 169.13.159.254169.13.159.2554,094
219169.13.160.0/20169.13.160.1 to 169.13.175.254169.13.175.2554,094
220169.13.176.0/20169.13.176.1 to 169.13.191.254169.13.191.2554,094
221169.13.192.0/20169.13.192.1 to 169.13.207.254169.13.207.2554,094
222169.13.208.0/20169.13.208.1 to 169.13.223.254169.13.223.2554,094
223169.13.224.0/20169.13.224.1 to 169.13.239.254169.13.239.2554,094
224169.13.240.0/20169.13.240.1 to 169.13.255.254169.13.255.2554,094
225169.14.0.0/20169.14.0.1 to 169.14.15.254169.14.15.2554,094
226169.14.16.0/20169.14.16.1 to 169.14.31.254169.14.31.2554,094
227169.14.32.0/20169.14.32.1 to 169.14.47.254169.14.47.2554,094
228169.14.48.0/20169.14.48.1 to 169.14.63.254169.14.63.2554,094
229169.14.64.0/20169.14.64.1 to 169.14.79.254169.14.79.2554,094
230169.14.80.0/20169.14.80.1 to 169.14.95.254169.14.95.2554,094
231169.14.96.0/20169.14.96.1 to 169.14.111.254169.14.111.2554,094
232169.14.112.0/20169.14.112.1 to 169.14.127.254169.14.127.2554,094
233169.14.128.0/20169.14.128.1 to 169.14.143.254169.14.143.2554,094
234169.14.144.0/20169.14.144.1 to 169.14.159.254169.14.159.2554,094
235169.14.160.0/20169.14.160.1 to 169.14.175.254169.14.175.2554,094
236169.14.176.0/20169.14.176.1 to 169.14.191.254169.14.191.2554,094
237169.14.192.0/20169.14.192.1 to 169.14.207.254169.14.207.2554,094
238169.14.208.0/20169.14.208.1 to 169.14.223.254169.14.223.2554,094
239169.14.224.0/20169.14.224.1 to 169.14.239.254169.14.239.2554,094
240169.14.240.0/20169.14.240.1 to 169.14.255.254169.14.255.2554,094
241169.15.0.0/20169.15.0.1 to 169.15.15.254169.15.15.2554,094
242169.15.16.0/20169.15.16.1 to 169.15.31.254169.15.31.2554,094
243169.15.32.0/20169.15.32.1 to 169.15.47.254169.15.47.2554,094
244169.15.48.0/20169.15.48.1 to 169.15.63.254169.15.63.2554,094
245169.15.64.0/20169.15.64.1 to 169.15.79.254169.15.79.2554,094
246169.15.80.0/20169.15.80.1 to 169.15.95.254169.15.95.2554,094
247169.15.96.0/20169.15.96.1 to 169.15.111.254169.15.111.2554,094
248169.15.112.0/20169.15.112.1 to 169.15.127.254169.15.127.2554,094
249169.15.128.0/20169.15.128.1 to 169.15.143.254169.15.143.2554,094
250169.15.144.0/20169.15.144.1 to 169.15.159.254169.15.159.2554,094
251169.15.160.0/20169.15.160.1 to 169.15.175.254169.15.175.2554,094
252169.15.176.0/20169.15.176.1 to 169.15.191.254169.15.191.2554,094
253169.15.192.0/20169.15.192.1 to 169.15.207.254169.15.207.2554,094
254169.15.208.0/20169.15.208.1 to 169.15.223.254169.15.223.2554,094
255169.15.224.0/20169.15.224.1 to 169.15.239.254169.15.239.2554,094
256169.15.240.0/20169.15.240.1 to 169.15.255.254169.15.255.2554,094

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.