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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.

Network106.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
106.0.0.0
Broadcast address
106.255.255.255
First usable
106.0.0.1
Last usable
106.255.255.254
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 6A000000 · Integer 1778384896 to 1795162111
Reverse DNS zone
106.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01101010..00000000.00000000.00000000106.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01101010..00000000.00000000.00000000106.0.0.0
Broadcast01101010..11111111.11111111.11111111106.255.255.255
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)

106.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1106.0.0.0/18106.0.0.1 to 106.0.63.254106.0.63.25516,382
2106.0.64.0/18106.0.64.1 to 106.0.127.254106.0.127.25516,382
3106.0.128.0/18106.0.128.1 to 106.0.191.254106.0.191.25516,382
4106.0.192.0/18106.0.192.1 to 106.0.255.254106.0.255.25516,382
5106.1.0.0/18106.1.0.1 to 106.1.63.254106.1.63.25516,382
6106.1.64.0/18106.1.64.1 to 106.1.127.254106.1.127.25516,382
7106.1.128.0/18106.1.128.1 to 106.1.191.254106.1.191.25516,382
8106.1.192.0/18106.1.192.1 to 106.1.255.254106.1.255.25516,382
9106.2.0.0/18106.2.0.1 to 106.2.63.254106.2.63.25516,382
10106.2.64.0/18106.2.64.1 to 106.2.127.254106.2.127.25516,382
11106.2.128.0/18106.2.128.1 to 106.2.191.254106.2.191.25516,382
12106.2.192.0/18106.2.192.1 to 106.2.255.254106.2.255.25516,382
13106.3.0.0/18106.3.0.1 to 106.3.63.254106.3.63.25516,382
14106.3.64.0/18106.3.64.1 to 106.3.127.254106.3.127.25516,382
15106.3.128.0/18106.3.128.1 to 106.3.191.254106.3.191.25516,382
16106.3.192.0/18106.3.192.1 to 106.3.255.254106.3.255.25516,382
17106.4.0.0/18106.4.0.1 to 106.4.63.254106.4.63.25516,382
18106.4.64.0/18106.4.64.1 to 106.4.127.254106.4.127.25516,382
19106.4.128.0/18106.4.128.1 to 106.4.191.254106.4.191.25516,382
20106.4.192.0/18106.4.192.1 to 106.4.255.254106.4.255.25516,382
21106.5.0.0/18106.5.0.1 to 106.5.63.254106.5.63.25516,382
22106.5.64.0/18106.5.64.1 to 106.5.127.254106.5.127.25516,382
23106.5.128.0/18106.5.128.1 to 106.5.191.254106.5.191.25516,382
24106.5.192.0/18106.5.192.1 to 106.5.255.254106.5.255.25516,382
25106.6.0.0/18106.6.0.1 to 106.6.63.254106.6.63.25516,382
26106.6.64.0/18106.6.64.1 to 106.6.127.254106.6.127.25516,382
27106.6.128.0/18106.6.128.1 to 106.6.191.254106.6.191.25516,382
28106.6.192.0/18106.6.192.1 to 106.6.255.254106.6.255.25516,382
29106.7.0.0/18106.7.0.1 to 106.7.63.254106.7.63.25516,382
30106.7.64.0/18106.7.64.1 to 106.7.127.254106.7.127.25516,382
31106.7.128.0/18106.7.128.1 to 106.7.191.254106.7.191.25516,382
32106.7.192.0/18106.7.192.1 to 106.7.255.254106.7.255.25516,382
33106.8.0.0/18106.8.0.1 to 106.8.63.254106.8.63.25516,382
34106.8.64.0/18106.8.64.1 to 106.8.127.254106.8.127.25516,382
35106.8.128.0/18106.8.128.1 to 106.8.191.254106.8.191.25516,382
36106.8.192.0/18106.8.192.1 to 106.8.255.254106.8.255.25516,382
37106.9.0.0/18106.9.0.1 to 106.9.63.254106.9.63.25516,382
38106.9.64.0/18106.9.64.1 to 106.9.127.254106.9.127.25516,382
39106.9.128.0/18106.9.128.1 to 106.9.191.254106.9.191.25516,382
40106.9.192.0/18106.9.192.1 to 106.9.255.254106.9.255.25516,382
41106.10.0.0/18106.10.0.1 to 106.10.63.254106.10.63.25516,382
42106.10.64.0/18106.10.64.1 to 106.10.127.254106.10.127.25516,382
43106.10.128.0/18106.10.128.1 to 106.10.191.254106.10.191.25516,382
44106.10.192.0/18106.10.192.1 to 106.10.255.254106.10.255.25516,382
45106.11.0.0/18106.11.0.1 to 106.11.63.254106.11.63.25516,382
46106.11.64.0/18106.11.64.1 to 106.11.127.254106.11.127.25516,382
47106.11.128.0/18106.11.128.1 to 106.11.191.254106.11.191.25516,382
48106.11.192.0/18106.11.192.1 to 106.11.255.254106.11.255.25516,382
49106.12.0.0/18106.12.0.1 to 106.12.63.254106.12.63.25516,382
50106.12.64.0/18106.12.64.1 to 106.12.127.254106.12.127.25516,382
51106.12.128.0/18106.12.128.1 to 106.12.191.254106.12.191.25516,382
52106.12.192.0/18106.12.192.1 to 106.12.255.254106.12.255.25516,382
53106.13.0.0/18106.13.0.1 to 106.13.63.254106.13.63.25516,382
54106.13.64.0/18106.13.64.1 to 106.13.127.254106.13.127.25516,382
55106.13.128.0/18106.13.128.1 to 106.13.191.254106.13.191.25516,382
56106.13.192.0/18106.13.192.1 to 106.13.255.254106.13.255.25516,382
57106.14.0.0/18106.14.0.1 to 106.14.63.254106.14.63.25516,382
58106.14.64.0/18106.14.64.1 to 106.14.127.254106.14.127.25516,382
59106.14.128.0/18106.14.128.1 to 106.14.191.254106.14.191.25516,382
60106.14.192.0/18106.14.192.1 to 106.14.255.254106.14.255.25516,382
61106.15.0.0/18106.15.0.1 to 106.15.63.254106.15.63.25516,382
62106.15.64.0/18106.15.64.1 to 106.15.127.254106.15.127.25516,382
63106.15.128.0/18106.15.128.1 to 106.15.191.254106.15.191.25516,382
64106.15.192.0/18106.15.192.1 to 106.15.255.254106.15.255.25516,382
65106.16.0.0/18106.16.0.1 to 106.16.63.254106.16.63.25516,382
66106.16.64.0/18106.16.64.1 to 106.16.127.254106.16.127.25516,382
67106.16.128.0/18106.16.128.1 to 106.16.191.254106.16.191.25516,382
68106.16.192.0/18106.16.192.1 to 106.16.255.254106.16.255.25516,382
69106.17.0.0/18106.17.0.1 to 106.17.63.254106.17.63.25516,382
70106.17.64.0/18106.17.64.1 to 106.17.127.254106.17.127.25516,382
71106.17.128.0/18106.17.128.1 to 106.17.191.254106.17.191.25516,382
72106.17.192.0/18106.17.192.1 to 106.17.255.254106.17.255.25516,382
73106.18.0.0/18106.18.0.1 to 106.18.63.254106.18.63.25516,382
74106.18.64.0/18106.18.64.1 to 106.18.127.254106.18.127.25516,382
75106.18.128.0/18106.18.128.1 to 106.18.191.254106.18.191.25516,382
76106.18.192.0/18106.18.192.1 to 106.18.255.254106.18.255.25516,382
77106.19.0.0/18106.19.0.1 to 106.19.63.254106.19.63.25516,382
78106.19.64.0/18106.19.64.1 to 106.19.127.254106.19.127.25516,382
79106.19.128.0/18106.19.128.1 to 106.19.191.254106.19.191.25516,382
80106.19.192.0/18106.19.192.1 to 106.19.255.254106.19.255.25516,382
81106.20.0.0/18106.20.0.1 to 106.20.63.254106.20.63.25516,382
82106.20.64.0/18106.20.64.1 to 106.20.127.254106.20.127.25516,382
83106.20.128.0/18106.20.128.1 to 106.20.191.254106.20.191.25516,382
84106.20.192.0/18106.20.192.1 to 106.20.255.254106.20.255.25516,382
85106.21.0.0/18106.21.0.1 to 106.21.63.254106.21.63.25516,382
86106.21.64.0/18106.21.64.1 to 106.21.127.254106.21.127.25516,382
87106.21.128.0/18106.21.128.1 to 106.21.191.254106.21.191.25516,382
88106.21.192.0/18106.21.192.1 to 106.21.255.254106.21.255.25516,382
89106.22.0.0/18106.22.0.1 to 106.22.63.254106.22.63.25516,382
90106.22.64.0/18106.22.64.1 to 106.22.127.254106.22.127.25516,382
91106.22.128.0/18106.22.128.1 to 106.22.191.254106.22.191.25516,382
92106.22.192.0/18106.22.192.1 to 106.22.255.254106.22.255.25516,382
93106.23.0.0/18106.23.0.1 to 106.23.63.254106.23.63.25516,382
94106.23.64.0/18106.23.64.1 to 106.23.127.254106.23.127.25516,382
95106.23.128.0/18106.23.128.1 to 106.23.191.254106.23.191.25516,382
96106.23.192.0/18106.23.192.1 to 106.23.255.254106.23.255.25516,382
97106.24.0.0/18106.24.0.1 to 106.24.63.254106.24.63.25516,382
98106.24.64.0/18106.24.64.1 to 106.24.127.254106.24.127.25516,382
99106.24.128.0/18106.24.128.1 to 106.24.191.254106.24.191.25516,382
100106.24.192.0/18106.24.192.1 to 106.24.255.254106.24.255.25516,382
101106.25.0.0/18106.25.0.1 to 106.25.63.254106.25.63.25516,382
102106.25.64.0/18106.25.64.1 to 106.25.127.254106.25.127.25516,382
103106.25.128.0/18106.25.128.1 to 106.25.191.254106.25.191.25516,382
104106.25.192.0/18106.25.192.1 to 106.25.255.254106.25.255.25516,382
105106.26.0.0/18106.26.0.1 to 106.26.63.254106.26.63.25516,382
106106.26.64.0/18106.26.64.1 to 106.26.127.254106.26.127.25516,382
107106.26.128.0/18106.26.128.1 to 106.26.191.254106.26.191.25516,382
108106.26.192.0/18106.26.192.1 to 106.26.255.254106.26.255.25516,382
109106.27.0.0/18106.27.0.1 to 106.27.63.254106.27.63.25516,382
110106.27.64.0/18106.27.64.1 to 106.27.127.254106.27.127.25516,382
111106.27.128.0/18106.27.128.1 to 106.27.191.254106.27.191.25516,382
112106.27.192.0/18106.27.192.1 to 106.27.255.254106.27.255.25516,382
113106.28.0.0/18106.28.0.1 to 106.28.63.254106.28.63.25516,382
114106.28.64.0/18106.28.64.1 to 106.28.127.254106.28.127.25516,382
115106.28.128.0/18106.28.128.1 to 106.28.191.254106.28.191.25516,382
116106.28.192.0/18106.28.192.1 to 106.28.255.254106.28.255.25516,382
117106.29.0.0/18106.29.0.1 to 106.29.63.254106.29.63.25516,382
118106.29.64.0/18106.29.64.1 to 106.29.127.254106.29.127.25516,382
119106.29.128.0/18106.29.128.1 to 106.29.191.254106.29.191.25516,382
120106.29.192.0/18106.29.192.1 to 106.29.255.254106.29.255.25516,382
121106.30.0.0/18106.30.0.1 to 106.30.63.254106.30.63.25516,382
122106.30.64.0/18106.30.64.1 to 106.30.127.254106.30.127.25516,382
123106.30.128.0/18106.30.128.1 to 106.30.191.254106.30.191.25516,382
124106.30.192.0/18106.30.192.1 to 106.30.255.254106.30.255.25516,382
125106.31.0.0/18106.31.0.1 to 106.31.63.254106.31.63.25516,382
126106.31.64.0/18106.31.64.1 to 106.31.127.254106.31.127.25516,382
127106.31.128.0/18106.31.128.1 to 106.31.191.254106.31.191.25516,382
128106.31.192.0/18106.31.192.1 to 106.31.255.254106.31.255.25516,382
129106.32.0.0/18106.32.0.1 to 106.32.63.254106.32.63.25516,382
130106.32.64.0/18106.32.64.1 to 106.32.127.254106.32.127.25516,382
131106.32.128.0/18106.32.128.1 to 106.32.191.254106.32.191.25516,382
132106.32.192.0/18106.32.192.1 to 106.32.255.254106.32.255.25516,382
133106.33.0.0/18106.33.0.1 to 106.33.63.254106.33.63.25516,382
134106.33.64.0/18106.33.64.1 to 106.33.127.254106.33.127.25516,382
135106.33.128.0/18106.33.128.1 to 106.33.191.254106.33.191.25516,382
136106.33.192.0/18106.33.192.1 to 106.33.255.254106.33.255.25516,382
137106.34.0.0/18106.34.0.1 to 106.34.63.254106.34.63.25516,382
138106.34.64.0/18106.34.64.1 to 106.34.127.254106.34.127.25516,382
139106.34.128.0/18106.34.128.1 to 106.34.191.254106.34.191.25516,382
140106.34.192.0/18106.34.192.1 to 106.34.255.254106.34.255.25516,382
141106.35.0.0/18106.35.0.1 to 106.35.63.254106.35.63.25516,382
142106.35.64.0/18106.35.64.1 to 106.35.127.254106.35.127.25516,382
143106.35.128.0/18106.35.128.1 to 106.35.191.254106.35.191.25516,382
144106.35.192.0/18106.35.192.1 to 106.35.255.254106.35.255.25516,382
145106.36.0.0/18106.36.0.1 to 106.36.63.254106.36.63.25516,382
146106.36.64.0/18106.36.64.1 to 106.36.127.254106.36.127.25516,382
147106.36.128.0/18106.36.128.1 to 106.36.191.254106.36.191.25516,382
148106.36.192.0/18106.36.192.1 to 106.36.255.254106.36.255.25516,382
149106.37.0.0/18106.37.0.1 to 106.37.63.254106.37.63.25516,382
150106.37.64.0/18106.37.64.1 to 106.37.127.254106.37.127.25516,382
151106.37.128.0/18106.37.128.1 to 106.37.191.254106.37.191.25516,382
152106.37.192.0/18106.37.192.1 to 106.37.255.254106.37.255.25516,382
153106.38.0.0/18106.38.0.1 to 106.38.63.254106.38.63.25516,382
154106.38.64.0/18106.38.64.1 to 106.38.127.254106.38.127.25516,382
155106.38.128.0/18106.38.128.1 to 106.38.191.254106.38.191.25516,382
156106.38.192.0/18106.38.192.1 to 106.38.255.254106.38.255.25516,382
157106.39.0.0/18106.39.0.1 to 106.39.63.254106.39.63.25516,382
158106.39.64.0/18106.39.64.1 to 106.39.127.254106.39.127.25516,382
159106.39.128.0/18106.39.128.1 to 106.39.191.254106.39.191.25516,382
160106.39.192.0/18106.39.192.1 to 106.39.255.254106.39.255.25516,382
161106.40.0.0/18106.40.0.1 to 106.40.63.254106.40.63.25516,382
162106.40.64.0/18106.40.64.1 to 106.40.127.254106.40.127.25516,382
163106.40.128.0/18106.40.128.1 to 106.40.191.254106.40.191.25516,382
164106.40.192.0/18106.40.192.1 to 106.40.255.254106.40.255.25516,382
165106.41.0.0/18106.41.0.1 to 106.41.63.254106.41.63.25516,382
166106.41.64.0/18106.41.64.1 to 106.41.127.254106.41.127.25516,382
167106.41.128.0/18106.41.128.1 to 106.41.191.254106.41.191.25516,382
168106.41.192.0/18106.41.192.1 to 106.41.255.254106.41.255.25516,382
169106.42.0.0/18106.42.0.1 to 106.42.63.254106.42.63.25516,382
170106.42.64.0/18106.42.64.1 to 106.42.127.254106.42.127.25516,382
171106.42.128.0/18106.42.128.1 to 106.42.191.254106.42.191.25516,382
172106.42.192.0/18106.42.192.1 to 106.42.255.254106.42.255.25516,382
173106.43.0.0/18106.43.0.1 to 106.43.63.254106.43.63.25516,382
174106.43.64.0/18106.43.64.1 to 106.43.127.254106.43.127.25516,382
175106.43.128.0/18106.43.128.1 to 106.43.191.254106.43.191.25516,382
176106.43.192.0/18106.43.192.1 to 106.43.255.254106.43.255.25516,382
177106.44.0.0/18106.44.0.1 to 106.44.63.254106.44.63.25516,382
178106.44.64.0/18106.44.64.1 to 106.44.127.254106.44.127.25516,382
179106.44.128.0/18106.44.128.1 to 106.44.191.254106.44.191.25516,382
180106.44.192.0/18106.44.192.1 to 106.44.255.254106.44.255.25516,382
181106.45.0.0/18106.45.0.1 to 106.45.63.254106.45.63.25516,382
182106.45.64.0/18106.45.64.1 to 106.45.127.254106.45.127.25516,382
183106.45.128.0/18106.45.128.1 to 106.45.191.254106.45.191.25516,382
184106.45.192.0/18106.45.192.1 to 106.45.255.254106.45.255.25516,382
185106.46.0.0/18106.46.0.1 to 106.46.63.254106.46.63.25516,382
186106.46.64.0/18106.46.64.1 to 106.46.127.254106.46.127.25516,382
187106.46.128.0/18106.46.128.1 to 106.46.191.254106.46.191.25516,382
188106.46.192.0/18106.46.192.1 to 106.46.255.254106.46.255.25516,382
189106.47.0.0/18106.47.0.1 to 106.47.63.254106.47.63.25516,382
190106.47.64.0/18106.47.64.1 to 106.47.127.254106.47.127.25516,382
191106.47.128.0/18106.47.128.1 to 106.47.191.254106.47.191.25516,382
192106.47.192.0/18106.47.192.1 to 106.47.255.254106.47.255.25516,382
193106.48.0.0/18106.48.0.1 to 106.48.63.254106.48.63.25516,382
194106.48.64.0/18106.48.64.1 to 106.48.127.254106.48.127.25516,382
195106.48.128.0/18106.48.128.1 to 106.48.191.254106.48.191.25516,382
196106.48.192.0/18106.48.192.1 to 106.48.255.254106.48.255.25516,382
197106.49.0.0/18106.49.0.1 to 106.49.63.254106.49.63.25516,382
198106.49.64.0/18106.49.64.1 to 106.49.127.254106.49.127.25516,382
199106.49.128.0/18106.49.128.1 to 106.49.191.254106.49.191.25516,382
200106.49.192.0/18106.49.192.1 to 106.49.255.254106.49.255.25516,382
201106.50.0.0/18106.50.0.1 to 106.50.63.254106.50.63.25516,382
202106.50.64.0/18106.50.64.1 to 106.50.127.254106.50.127.25516,382
203106.50.128.0/18106.50.128.1 to 106.50.191.254106.50.191.25516,382
204106.50.192.0/18106.50.192.1 to 106.50.255.254106.50.255.25516,382
205106.51.0.0/18106.51.0.1 to 106.51.63.254106.51.63.25516,382
206106.51.64.0/18106.51.64.1 to 106.51.127.254106.51.127.25516,382
207106.51.128.0/18106.51.128.1 to 106.51.191.254106.51.191.25516,382
208106.51.192.0/18106.51.192.1 to 106.51.255.254106.51.255.25516,382
209106.52.0.0/18106.52.0.1 to 106.52.63.254106.52.63.25516,382
210106.52.64.0/18106.52.64.1 to 106.52.127.254106.52.127.25516,382
211106.52.128.0/18106.52.128.1 to 106.52.191.254106.52.191.25516,382
212106.52.192.0/18106.52.192.1 to 106.52.255.254106.52.255.25516,382
213106.53.0.0/18106.53.0.1 to 106.53.63.254106.53.63.25516,382
214106.53.64.0/18106.53.64.1 to 106.53.127.254106.53.127.25516,382
215106.53.128.0/18106.53.128.1 to 106.53.191.254106.53.191.25516,382
216106.53.192.0/18106.53.192.1 to 106.53.255.254106.53.255.25516,382
217106.54.0.0/18106.54.0.1 to 106.54.63.254106.54.63.25516,382
218106.54.64.0/18106.54.64.1 to 106.54.127.254106.54.127.25516,382
219106.54.128.0/18106.54.128.1 to 106.54.191.254106.54.191.25516,382
220106.54.192.0/18106.54.192.1 to 106.54.255.254106.54.255.25516,382
221106.55.0.0/18106.55.0.1 to 106.55.63.254106.55.63.25516,382
222106.55.64.0/18106.55.64.1 to 106.55.127.254106.55.127.25516,382
223106.55.128.0/18106.55.128.1 to 106.55.191.254106.55.191.25516,382
224106.55.192.0/18106.55.192.1 to 106.55.255.254106.55.255.25516,382
225106.56.0.0/18106.56.0.1 to 106.56.63.254106.56.63.25516,382
226106.56.64.0/18106.56.64.1 to 106.56.127.254106.56.127.25516,382
227106.56.128.0/18106.56.128.1 to 106.56.191.254106.56.191.25516,382
228106.56.192.0/18106.56.192.1 to 106.56.255.254106.56.255.25516,382
229106.57.0.0/18106.57.0.1 to 106.57.63.254106.57.63.25516,382
230106.57.64.0/18106.57.64.1 to 106.57.127.254106.57.127.25516,382
231106.57.128.0/18106.57.128.1 to 106.57.191.254106.57.191.25516,382
232106.57.192.0/18106.57.192.1 to 106.57.255.254106.57.255.25516,382
233106.58.0.0/18106.58.0.1 to 106.58.63.254106.58.63.25516,382
234106.58.64.0/18106.58.64.1 to 106.58.127.254106.58.127.25516,382
235106.58.128.0/18106.58.128.1 to 106.58.191.254106.58.191.25516,382
236106.58.192.0/18106.58.192.1 to 106.58.255.254106.58.255.25516,382
237106.59.0.0/18106.59.0.1 to 106.59.63.254106.59.63.25516,382
238106.59.64.0/18106.59.64.1 to 106.59.127.254106.59.127.25516,382
239106.59.128.0/18106.59.128.1 to 106.59.191.254106.59.191.25516,382
240106.59.192.0/18106.59.192.1 to 106.59.255.254106.59.255.25516,382
241106.60.0.0/18106.60.0.1 to 106.60.63.254106.60.63.25516,382
242106.60.64.0/18106.60.64.1 to 106.60.127.254106.60.127.25516,382
243106.60.128.0/18106.60.128.1 to 106.60.191.254106.60.191.25516,382
244106.60.192.0/18106.60.192.1 to 106.60.255.254106.60.255.25516,382
245106.61.0.0/18106.61.0.1 to 106.61.63.254106.61.63.25516,382
246106.61.64.0/18106.61.64.1 to 106.61.127.254106.61.127.25516,382
247106.61.128.0/18106.61.128.1 to 106.61.191.254106.61.191.25516,382
248106.61.192.0/18106.61.192.1 to 106.61.255.254106.61.255.25516,382
249106.62.0.0/18106.62.0.1 to 106.62.63.254106.62.63.25516,382
250106.62.64.0/18106.62.64.1 to 106.62.127.254106.62.127.25516,382
251106.62.128.0/18106.62.128.1 to 106.62.191.254106.62.191.25516,382
252106.62.192.0/18106.62.192.1 to 106.62.255.254106.62.255.25516,382
253106.63.0.0/18106.63.0.1 to 106.63.63.254106.63.63.25516,382
254106.63.64.0/18106.63.64.1 to 106.63.127.254106.63.127.25516,382
255106.63.128.0/18106.63.128.1 to 106.63.191.254106.63.191.25516,382
256106.63.192.0/18106.63.192.1 to 106.63.255.254106.63.255.25516,382

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.