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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.

Network109.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
109.0.0.0
Broadcast address
109.255.255.255
First usable
109.0.0.1
Last usable
109.255.255.254
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
A (default /8)
As numbers
Hex 6D000000 · Integer 1828716544 to 1845493759
Reverse DNS zone
109.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01101101..00000000.00000000.00000000109.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01101101..00000000.00000000.00000000109.0.0.0
Broadcast01101101..11111111.11111111.11111111109.255.255.255
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)

109.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1109.0.0.0/20109.0.0.1 to 109.0.15.254109.0.15.2554,094
2109.0.16.0/20109.0.16.1 to 109.0.31.254109.0.31.2554,094
3109.0.32.0/20109.0.32.1 to 109.0.47.254109.0.47.2554,094
4109.0.48.0/20109.0.48.1 to 109.0.63.254109.0.63.2554,094
5109.0.64.0/20109.0.64.1 to 109.0.79.254109.0.79.2554,094
6109.0.80.0/20109.0.80.1 to 109.0.95.254109.0.95.2554,094
7109.0.96.0/20109.0.96.1 to 109.0.111.254109.0.111.2554,094
8109.0.112.0/20109.0.112.1 to 109.0.127.254109.0.127.2554,094
9109.0.128.0/20109.0.128.1 to 109.0.143.254109.0.143.2554,094
10109.0.144.0/20109.0.144.1 to 109.0.159.254109.0.159.2554,094
11109.0.160.0/20109.0.160.1 to 109.0.175.254109.0.175.2554,094
12109.0.176.0/20109.0.176.1 to 109.0.191.254109.0.191.2554,094
13109.0.192.0/20109.0.192.1 to 109.0.207.254109.0.207.2554,094
14109.0.208.0/20109.0.208.1 to 109.0.223.254109.0.223.2554,094
15109.0.224.0/20109.0.224.1 to 109.0.239.254109.0.239.2554,094
16109.0.240.0/20109.0.240.1 to 109.0.255.254109.0.255.2554,094
17109.1.0.0/20109.1.0.1 to 109.1.15.254109.1.15.2554,094
18109.1.16.0/20109.1.16.1 to 109.1.31.254109.1.31.2554,094
19109.1.32.0/20109.1.32.1 to 109.1.47.254109.1.47.2554,094
20109.1.48.0/20109.1.48.1 to 109.1.63.254109.1.63.2554,094
21109.1.64.0/20109.1.64.1 to 109.1.79.254109.1.79.2554,094
22109.1.80.0/20109.1.80.1 to 109.1.95.254109.1.95.2554,094
23109.1.96.0/20109.1.96.1 to 109.1.111.254109.1.111.2554,094
24109.1.112.0/20109.1.112.1 to 109.1.127.254109.1.127.2554,094
25109.1.128.0/20109.1.128.1 to 109.1.143.254109.1.143.2554,094
26109.1.144.0/20109.1.144.1 to 109.1.159.254109.1.159.2554,094
27109.1.160.0/20109.1.160.1 to 109.1.175.254109.1.175.2554,094
28109.1.176.0/20109.1.176.1 to 109.1.191.254109.1.191.2554,094
29109.1.192.0/20109.1.192.1 to 109.1.207.254109.1.207.2554,094
30109.1.208.0/20109.1.208.1 to 109.1.223.254109.1.223.2554,094
31109.1.224.0/20109.1.224.1 to 109.1.239.254109.1.239.2554,094
32109.1.240.0/20109.1.240.1 to 109.1.255.254109.1.255.2554,094
33109.2.0.0/20109.2.0.1 to 109.2.15.254109.2.15.2554,094
34109.2.16.0/20109.2.16.1 to 109.2.31.254109.2.31.2554,094
35109.2.32.0/20109.2.32.1 to 109.2.47.254109.2.47.2554,094
36109.2.48.0/20109.2.48.1 to 109.2.63.254109.2.63.2554,094
37109.2.64.0/20109.2.64.1 to 109.2.79.254109.2.79.2554,094
38109.2.80.0/20109.2.80.1 to 109.2.95.254109.2.95.2554,094
39109.2.96.0/20109.2.96.1 to 109.2.111.254109.2.111.2554,094
40109.2.112.0/20109.2.112.1 to 109.2.127.254109.2.127.2554,094
41109.2.128.0/20109.2.128.1 to 109.2.143.254109.2.143.2554,094
42109.2.144.0/20109.2.144.1 to 109.2.159.254109.2.159.2554,094
43109.2.160.0/20109.2.160.1 to 109.2.175.254109.2.175.2554,094
44109.2.176.0/20109.2.176.1 to 109.2.191.254109.2.191.2554,094
45109.2.192.0/20109.2.192.1 to 109.2.207.254109.2.207.2554,094
46109.2.208.0/20109.2.208.1 to 109.2.223.254109.2.223.2554,094
47109.2.224.0/20109.2.224.1 to 109.2.239.254109.2.239.2554,094
48109.2.240.0/20109.2.240.1 to 109.2.255.254109.2.255.2554,094
49109.3.0.0/20109.3.0.1 to 109.3.15.254109.3.15.2554,094
50109.3.16.0/20109.3.16.1 to 109.3.31.254109.3.31.2554,094
51109.3.32.0/20109.3.32.1 to 109.3.47.254109.3.47.2554,094
52109.3.48.0/20109.3.48.1 to 109.3.63.254109.3.63.2554,094
53109.3.64.0/20109.3.64.1 to 109.3.79.254109.3.79.2554,094
54109.3.80.0/20109.3.80.1 to 109.3.95.254109.3.95.2554,094
55109.3.96.0/20109.3.96.1 to 109.3.111.254109.3.111.2554,094
56109.3.112.0/20109.3.112.1 to 109.3.127.254109.3.127.2554,094
57109.3.128.0/20109.3.128.1 to 109.3.143.254109.3.143.2554,094
58109.3.144.0/20109.3.144.1 to 109.3.159.254109.3.159.2554,094
59109.3.160.0/20109.3.160.1 to 109.3.175.254109.3.175.2554,094
60109.3.176.0/20109.3.176.1 to 109.3.191.254109.3.191.2554,094
61109.3.192.0/20109.3.192.1 to 109.3.207.254109.3.207.2554,094
62109.3.208.0/20109.3.208.1 to 109.3.223.254109.3.223.2554,094
63109.3.224.0/20109.3.224.1 to 109.3.239.254109.3.239.2554,094
64109.3.240.0/20109.3.240.1 to 109.3.255.254109.3.255.2554,094
65109.4.0.0/20109.4.0.1 to 109.4.15.254109.4.15.2554,094
66109.4.16.0/20109.4.16.1 to 109.4.31.254109.4.31.2554,094
67109.4.32.0/20109.4.32.1 to 109.4.47.254109.4.47.2554,094
68109.4.48.0/20109.4.48.1 to 109.4.63.254109.4.63.2554,094
69109.4.64.0/20109.4.64.1 to 109.4.79.254109.4.79.2554,094
70109.4.80.0/20109.4.80.1 to 109.4.95.254109.4.95.2554,094
71109.4.96.0/20109.4.96.1 to 109.4.111.254109.4.111.2554,094
72109.4.112.0/20109.4.112.1 to 109.4.127.254109.4.127.2554,094
73109.4.128.0/20109.4.128.1 to 109.4.143.254109.4.143.2554,094
74109.4.144.0/20109.4.144.1 to 109.4.159.254109.4.159.2554,094
75109.4.160.0/20109.4.160.1 to 109.4.175.254109.4.175.2554,094
76109.4.176.0/20109.4.176.1 to 109.4.191.254109.4.191.2554,094
77109.4.192.0/20109.4.192.1 to 109.4.207.254109.4.207.2554,094
78109.4.208.0/20109.4.208.1 to 109.4.223.254109.4.223.2554,094
79109.4.224.0/20109.4.224.1 to 109.4.239.254109.4.239.2554,094
80109.4.240.0/20109.4.240.1 to 109.4.255.254109.4.255.2554,094
81109.5.0.0/20109.5.0.1 to 109.5.15.254109.5.15.2554,094
82109.5.16.0/20109.5.16.1 to 109.5.31.254109.5.31.2554,094
83109.5.32.0/20109.5.32.1 to 109.5.47.254109.5.47.2554,094
84109.5.48.0/20109.5.48.1 to 109.5.63.254109.5.63.2554,094
85109.5.64.0/20109.5.64.1 to 109.5.79.254109.5.79.2554,094
86109.5.80.0/20109.5.80.1 to 109.5.95.254109.5.95.2554,094
87109.5.96.0/20109.5.96.1 to 109.5.111.254109.5.111.2554,094
88109.5.112.0/20109.5.112.1 to 109.5.127.254109.5.127.2554,094
89109.5.128.0/20109.5.128.1 to 109.5.143.254109.5.143.2554,094
90109.5.144.0/20109.5.144.1 to 109.5.159.254109.5.159.2554,094
91109.5.160.0/20109.5.160.1 to 109.5.175.254109.5.175.2554,094
92109.5.176.0/20109.5.176.1 to 109.5.191.254109.5.191.2554,094
93109.5.192.0/20109.5.192.1 to 109.5.207.254109.5.207.2554,094
94109.5.208.0/20109.5.208.1 to 109.5.223.254109.5.223.2554,094
95109.5.224.0/20109.5.224.1 to 109.5.239.254109.5.239.2554,094
96109.5.240.0/20109.5.240.1 to 109.5.255.254109.5.255.2554,094
97109.6.0.0/20109.6.0.1 to 109.6.15.254109.6.15.2554,094
98109.6.16.0/20109.6.16.1 to 109.6.31.254109.6.31.2554,094
99109.6.32.0/20109.6.32.1 to 109.6.47.254109.6.47.2554,094
100109.6.48.0/20109.6.48.1 to 109.6.63.254109.6.63.2554,094
101109.6.64.0/20109.6.64.1 to 109.6.79.254109.6.79.2554,094
102109.6.80.0/20109.6.80.1 to 109.6.95.254109.6.95.2554,094
103109.6.96.0/20109.6.96.1 to 109.6.111.254109.6.111.2554,094
104109.6.112.0/20109.6.112.1 to 109.6.127.254109.6.127.2554,094
105109.6.128.0/20109.6.128.1 to 109.6.143.254109.6.143.2554,094
106109.6.144.0/20109.6.144.1 to 109.6.159.254109.6.159.2554,094
107109.6.160.0/20109.6.160.1 to 109.6.175.254109.6.175.2554,094
108109.6.176.0/20109.6.176.1 to 109.6.191.254109.6.191.2554,094
109109.6.192.0/20109.6.192.1 to 109.6.207.254109.6.207.2554,094
110109.6.208.0/20109.6.208.1 to 109.6.223.254109.6.223.2554,094
111109.6.224.0/20109.6.224.1 to 109.6.239.254109.6.239.2554,094
112109.6.240.0/20109.6.240.1 to 109.6.255.254109.6.255.2554,094
113109.7.0.0/20109.7.0.1 to 109.7.15.254109.7.15.2554,094
114109.7.16.0/20109.7.16.1 to 109.7.31.254109.7.31.2554,094
115109.7.32.0/20109.7.32.1 to 109.7.47.254109.7.47.2554,094
116109.7.48.0/20109.7.48.1 to 109.7.63.254109.7.63.2554,094
117109.7.64.0/20109.7.64.1 to 109.7.79.254109.7.79.2554,094
118109.7.80.0/20109.7.80.1 to 109.7.95.254109.7.95.2554,094
119109.7.96.0/20109.7.96.1 to 109.7.111.254109.7.111.2554,094
120109.7.112.0/20109.7.112.1 to 109.7.127.254109.7.127.2554,094
121109.7.128.0/20109.7.128.1 to 109.7.143.254109.7.143.2554,094
122109.7.144.0/20109.7.144.1 to 109.7.159.254109.7.159.2554,094
123109.7.160.0/20109.7.160.1 to 109.7.175.254109.7.175.2554,094
124109.7.176.0/20109.7.176.1 to 109.7.191.254109.7.191.2554,094
125109.7.192.0/20109.7.192.1 to 109.7.207.254109.7.207.2554,094
126109.7.208.0/20109.7.208.1 to 109.7.223.254109.7.223.2554,094
127109.7.224.0/20109.7.224.1 to 109.7.239.254109.7.239.2554,094
128109.7.240.0/20109.7.240.1 to 109.7.255.254109.7.255.2554,094
129109.8.0.0/20109.8.0.1 to 109.8.15.254109.8.15.2554,094
130109.8.16.0/20109.8.16.1 to 109.8.31.254109.8.31.2554,094
131109.8.32.0/20109.8.32.1 to 109.8.47.254109.8.47.2554,094
132109.8.48.0/20109.8.48.1 to 109.8.63.254109.8.63.2554,094
133109.8.64.0/20109.8.64.1 to 109.8.79.254109.8.79.2554,094
134109.8.80.0/20109.8.80.1 to 109.8.95.254109.8.95.2554,094
135109.8.96.0/20109.8.96.1 to 109.8.111.254109.8.111.2554,094
136109.8.112.0/20109.8.112.1 to 109.8.127.254109.8.127.2554,094
137109.8.128.0/20109.8.128.1 to 109.8.143.254109.8.143.2554,094
138109.8.144.0/20109.8.144.1 to 109.8.159.254109.8.159.2554,094
139109.8.160.0/20109.8.160.1 to 109.8.175.254109.8.175.2554,094
140109.8.176.0/20109.8.176.1 to 109.8.191.254109.8.191.2554,094
141109.8.192.0/20109.8.192.1 to 109.8.207.254109.8.207.2554,094
142109.8.208.0/20109.8.208.1 to 109.8.223.254109.8.223.2554,094
143109.8.224.0/20109.8.224.1 to 109.8.239.254109.8.239.2554,094
144109.8.240.0/20109.8.240.1 to 109.8.255.254109.8.255.2554,094
145109.9.0.0/20109.9.0.1 to 109.9.15.254109.9.15.2554,094
146109.9.16.0/20109.9.16.1 to 109.9.31.254109.9.31.2554,094
147109.9.32.0/20109.9.32.1 to 109.9.47.254109.9.47.2554,094
148109.9.48.0/20109.9.48.1 to 109.9.63.254109.9.63.2554,094
149109.9.64.0/20109.9.64.1 to 109.9.79.254109.9.79.2554,094
150109.9.80.0/20109.9.80.1 to 109.9.95.254109.9.95.2554,094
151109.9.96.0/20109.9.96.1 to 109.9.111.254109.9.111.2554,094
152109.9.112.0/20109.9.112.1 to 109.9.127.254109.9.127.2554,094
153109.9.128.0/20109.9.128.1 to 109.9.143.254109.9.143.2554,094
154109.9.144.0/20109.9.144.1 to 109.9.159.254109.9.159.2554,094
155109.9.160.0/20109.9.160.1 to 109.9.175.254109.9.175.2554,094
156109.9.176.0/20109.9.176.1 to 109.9.191.254109.9.191.2554,094
157109.9.192.0/20109.9.192.1 to 109.9.207.254109.9.207.2554,094
158109.9.208.0/20109.9.208.1 to 109.9.223.254109.9.223.2554,094
159109.9.224.0/20109.9.224.1 to 109.9.239.254109.9.239.2554,094
160109.9.240.0/20109.9.240.1 to 109.9.255.254109.9.255.2554,094
161109.10.0.0/20109.10.0.1 to 109.10.15.254109.10.15.2554,094
162109.10.16.0/20109.10.16.1 to 109.10.31.254109.10.31.2554,094
163109.10.32.0/20109.10.32.1 to 109.10.47.254109.10.47.2554,094
164109.10.48.0/20109.10.48.1 to 109.10.63.254109.10.63.2554,094
165109.10.64.0/20109.10.64.1 to 109.10.79.254109.10.79.2554,094
166109.10.80.0/20109.10.80.1 to 109.10.95.254109.10.95.2554,094
167109.10.96.0/20109.10.96.1 to 109.10.111.254109.10.111.2554,094
168109.10.112.0/20109.10.112.1 to 109.10.127.254109.10.127.2554,094
169109.10.128.0/20109.10.128.1 to 109.10.143.254109.10.143.2554,094
170109.10.144.0/20109.10.144.1 to 109.10.159.254109.10.159.2554,094
171109.10.160.0/20109.10.160.1 to 109.10.175.254109.10.175.2554,094
172109.10.176.0/20109.10.176.1 to 109.10.191.254109.10.191.2554,094
173109.10.192.0/20109.10.192.1 to 109.10.207.254109.10.207.2554,094
174109.10.208.0/20109.10.208.1 to 109.10.223.254109.10.223.2554,094
175109.10.224.0/20109.10.224.1 to 109.10.239.254109.10.239.2554,094
176109.10.240.0/20109.10.240.1 to 109.10.255.254109.10.255.2554,094
177109.11.0.0/20109.11.0.1 to 109.11.15.254109.11.15.2554,094
178109.11.16.0/20109.11.16.1 to 109.11.31.254109.11.31.2554,094
179109.11.32.0/20109.11.32.1 to 109.11.47.254109.11.47.2554,094
180109.11.48.0/20109.11.48.1 to 109.11.63.254109.11.63.2554,094
181109.11.64.0/20109.11.64.1 to 109.11.79.254109.11.79.2554,094
182109.11.80.0/20109.11.80.1 to 109.11.95.254109.11.95.2554,094
183109.11.96.0/20109.11.96.1 to 109.11.111.254109.11.111.2554,094
184109.11.112.0/20109.11.112.1 to 109.11.127.254109.11.127.2554,094
185109.11.128.0/20109.11.128.1 to 109.11.143.254109.11.143.2554,094
186109.11.144.0/20109.11.144.1 to 109.11.159.254109.11.159.2554,094
187109.11.160.0/20109.11.160.1 to 109.11.175.254109.11.175.2554,094
188109.11.176.0/20109.11.176.1 to 109.11.191.254109.11.191.2554,094
189109.11.192.0/20109.11.192.1 to 109.11.207.254109.11.207.2554,094
190109.11.208.0/20109.11.208.1 to 109.11.223.254109.11.223.2554,094
191109.11.224.0/20109.11.224.1 to 109.11.239.254109.11.239.2554,094
192109.11.240.0/20109.11.240.1 to 109.11.255.254109.11.255.2554,094
193109.12.0.0/20109.12.0.1 to 109.12.15.254109.12.15.2554,094
194109.12.16.0/20109.12.16.1 to 109.12.31.254109.12.31.2554,094
195109.12.32.0/20109.12.32.1 to 109.12.47.254109.12.47.2554,094
196109.12.48.0/20109.12.48.1 to 109.12.63.254109.12.63.2554,094
197109.12.64.0/20109.12.64.1 to 109.12.79.254109.12.79.2554,094
198109.12.80.0/20109.12.80.1 to 109.12.95.254109.12.95.2554,094
199109.12.96.0/20109.12.96.1 to 109.12.111.254109.12.111.2554,094
200109.12.112.0/20109.12.112.1 to 109.12.127.254109.12.127.2554,094
201109.12.128.0/20109.12.128.1 to 109.12.143.254109.12.143.2554,094
202109.12.144.0/20109.12.144.1 to 109.12.159.254109.12.159.2554,094
203109.12.160.0/20109.12.160.1 to 109.12.175.254109.12.175.2554,094
204109.12.176.0/20109.12.176.1 to 109.12.191.254109.12.191.2554,094
205109.12.192.0/20109.12.192.1 to 109.12.207.254109.12.207.2554,094
206109.12.208.0/20109.12.208.1 to 109.12.223.254109.12.223.2554,094
207109.12.224.0/20109.12.224.1 to 109.12.239.254109.12.239.2554,094
208109.12.240.0/20109.12.240.1 to 109.12.255.254109.12.255.2554,094
209109.13.0.0/20109.13.0.1 to 109.13.15.254109.13.15.2554,094
210109.13.16.0/20109.13.16.1 to 109.13.31.254109.13.31.2554,094
211109.13.32.0/20109.13.32.1 to 109.13.47.254109.13.47.2554,094
212109.13.48.0/20109.13.48.1 to 109.13.63.254109.13.63.2554,094
213109.13.64.0/20109.13.64.1 to 109.13.79.254109.13.79.2554,094
214109.13.80.0/20109.13.80.1 to 109.13.95.254109.13.95.2554,094
215109.13.96.0/20109.13.96.1 to 109.13.111.254109.13.111.2554,094
216109.13.112.0/20109.13.112.1 to 109.13.127.254109.13.127.2554,094
217109.13.128.0/20109.13.128.1 to 109.13.143.254109.13.143.2554,094
218109.13.144.0/20109.13.144.1 to 109.13.159.254109.13.159.2554,094
219109.13.160.0/20109.13.160.1 to 109.13.175.254109.13.175.2554,094
220109.13.176.0/20109.13.176.1 to 109.13.191.254109.13.191.2554,094
221109.13.192.0/20109.13.192.1 to 109.13.207.254109.13.207.2554,094
222109.13.208.0/20109.13.208.1 to 109.13.223.254109.13.223.2554,094
223109.13.224.0/20109.13.224.1 to 109.13.239.254109.13.239.2554,094
224109.13.240.0/20109.13.240.1 to 109.13.255.254109.13.255.2554,094
225109.14.0.0/20109.14.0.1 to 109.14.15.254109.14.15.2554,094
226109.14.16.0/20109.14.16.1 to 109.14.31.254109.14.31.2554,094
227109.14.32.0/20109.14.32.1 to 109.14.47.254109.14.47.2554,094
228109.14.48.0/20109.14.48.1 to 109.14.63.254109.14.63.2554,094
229109.14.64.0/20109.14.64.1 to 109.14.79.254109.14.79.2554,094
230109.14.80.0/20109.14.80.1 to 109.14.95.254109.14.95.2554,094
231109.14.96.0/20109.14.96.1 to 109.14.111.254109.14.111.2554,094
232109.14.112.0/20109.14.112.1 to 109.14.127.254109.14.127.2554,094
233109.14.128.0/20109.14.128.1 to 109.14.143.254109.14.143.2554,094
234109.14.144.0/20109.14.144.1 to 109.14.159.254109.14.159.2554,094
235109.14.160.0/20109.14.160.1 to 109.14.175.254109.14.175.2554,094
236109.14.176.0/20109.14.176.1 to 109.14.191.254109.14.191.2554,094
237109.14.192.0/20109.14.192.1 to 109.14.207.254109.14.207.2554,094
238109.14.208.0/20109.14.208.1 to 109.14.223.254109.14.223.2554,094
239109.14.224.0/20109.14.224.1 to 109.14.239.254109.14.239.2554,094
240109.14.240.0/20109.14.240.1 to 109.14.255.254109.14.255.2554,094
241109.15.0.0/20109.15.0.1 to 109.15.15.254109.15.15.2554,094
242109.15.16.0/20109.15.16.1 to 109.15.31.254109.15.31.2554,094
243109.15.32.0/20109.15.32.1 to 109.15.47.254109.15.47.2554,094
244109.15.48.0/20109.15.48.1 to 109.15.63.254109.15.63.2554,094
245109.15.64.0/20109.15.64.1 to 109.15.79.254109.15.79.2554,094
246109.15.80.0/20109.15.80.1 to 109.15.95.254109.15.95.2554,094
247109.15.96.0/20109.15.96.1 to 109.15.111.254109.15.111.2554,094
248109.15.112.0/20109.15.112.1 to 109.15.127.254109.15.127.2554,094
249109.15.128.0/20109.15.128.1 to 109.15.143.254109.15.143.2554,094
250109.15.144.0/20109.15.144.1 to 109.15.159.254109.15.159.2554,094
251109.15.160.0/20109.15.160.1 to 109.15.175.254109.15.175.2554,094
252109.15.176.0/20109.15.176.1 to 109.15.191.254109.15.191.2554,094
253109.15.192.0/20109.15.192.1 to 109.15.207.254109.15.207.2554,094
254109.15.208.0/20109.15.208.1 to 109.15.223.254109.15.223.2554,094
255109.15.224.0/20109.15.224.1 to 109.15.239.254109.15.239.2554,094
256109.15.240.0/20109.15.240.1 to 109.15.255.254109.15.255.2554,094

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.