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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.

Network146.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
146.0.0.0
Broadcast address
146.255.255.255
First usable
146.0.0.1
Last usable
146.255.255.254
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 92000000 · Integer 2449473536 to 2466250751
Reverse DNS zone
146.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10010010..00000000.00000000.00000000146.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10010010..00000000.00000000.00000000146.0.0.0
Broadcast10010010..11111111.11111111.11111111146.255.255.255
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)

146.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1146.0.0.0/18146.0.0.1 to 146.0.63.254146.0.63.25516,382
2146.0.64.0/18146.0.64.1 to 146.0.127.254146.0.127.25516,382
3146.0.128.0/18146.0.128.1 to 146.0.191.254146.0.191.25516,382
4146.0.192.0/18146.0.192.1 to 146.0.255.254146.0.255.25516,382
5146.1.0.0/18146.1.0.1 to 146.1.63.254146.1.63.25516,382
6146.1.64.0/18146.1.64.1 to 146.1.127.254146.1.127.25516,382
7146.1.128.0/18146.1.128.1 to 146.1.191.254146.1.191.25516,382
8146.1.192.0/18146.1.192.1 to 146.1.255.254146.1.255.25516,382
9146.2.0.0/18146.2.0.1 to 146.2.63.254146.2.63.25516,382
10146.2.64.0/18146.2.64.1 to 146.2.127.254146.2.127.25516,382
11146.2.128.0/18146.2.128.1 to 146.2.191.254146.2.191.25516,382
12146.2.192.0/18146.2.192.1 to 146.2.255.254146.2.255.25516,382
13146.3.0.0/18146.3.0.1 to 146.3.63.254146.3.63.25516,382
14146.3.64.0/18146.3.64.1 to 146.3.127.254146.3.127.25516,382
15146.3.128.0/18146.3.128.1 to 146.3.191.254146.3.191.25516,382
16146.3.192.0/18146.3.192.1 to 146.3.255.254146.3.255.25516,382
17146.4.0.0/18146.4.0.1 to 146.4.63.254146.4.63.25516,382
18146.4.64.0/18146.4.64.1 to 146.4.127.254146.4.127.25516,382
19146.4.128.0/18146.4.128.1 to 146.4.191.254146.4.191.25516,382
20146.4.192.0/18146.4.192.1 to 146.4.255.254146.4.255.25516,382
21146.5.0.0/18146.5.0.1 to 146.5.63.254146.5.63.25516,382
22146.5.64.0/18146.5.64.1 to 146.5.127.254146.5.127.25516,382
23146.5.128.0/18146.5.128.1 to 146.5.191.254146.5.191.25516,382
24146.5.192.0/18146.5.192.1 to 146.5.255.254146.5.255.25516,382
25146.6.0.0/18146.6.0.1 to 146.6.63.254146.6.63.25516,382
26146.6.64.0/18146.6.64.1 to 146.6.127.254146.6.127.25516,382
27146.6.128.0/18146.6.128.1 to 146.6.191.254146.6.191.25516,382
28146.6.192.0/18146.6.192.1 to 146.6.255.254146.6.255.25516,382
29146.7.0.0/18146.7.0.1 to 146.7.63.254146.7.63.25516,382
30146.7.64.0/18146.7.64.1 to 146.7.127.254146.7.127.25516,382
31146.7.128.0/18146.7.128.1 to 146.7.191.254146.7.191.25516,382
32146.7.192.0/18146.7.192.1 to 146.7.255.254146.7.255.25516,382
33146.8.0.0/18146.8.0.1 to 146.8.63.254146.8.63.25516,382
34146.8.64.0/18146.8.64.1 to 146.8.127.254146.8.127.25516,382
35146.8.128.0/18146.8.128.1 to 146.8.191.254146.8.191.25516,382
36146.8.192.0/18146.8.192.1 to 146.8.255.254146.8.255.25516,382
37146.9.0.0/18146.9.0.1 to 146.9.63.254146.9.63.25516,382
38146.9.64.0/18146.9.64.1 to 146.9.127.254146.9.127.25516,382
39146.9.128.0/18146.9.128.1 to 146.9.191.254146.9.191.25516,382
40146.9.192.0/18146.9.192.1 to 146.9.255.254146.9.255.25516,382
41146.10.0.0/18146.10.0.1 to 146.10.63.254146.10.63.25516,382
42146.10.64.0/18146.10.64.1 to 146.10.127.254146.10.127.25516,382
43146.10.128.0/18146.10.128.1 to 146.10.191.254146.10.191.25516,382
44146.10.192.0/18146.10.192.1 to 146.10.255.254146.10.255.25516,382
45146.11.0.0/18146.11.0.1 to 146.11.63.254146.11.63.25516,382
46146.11.64.0/18146.11.64.1 to 146.11.127.254146.11.127.25516,382
47146.11.128.0/18146.11.128.1 to 146.11.191.254146.11.191.25516,382
48146.11.192.0/18146.11.192.1 to 146.11.255.254146.11.255.25516,382
49146.12.0.0/18146.12.0.1 to 146.12.63.254146.12.63.25516,382
50146.12.64.0/18146.12.64.1 to 146.12.127.254146.12.127.25516,382
51146.12.128.0/18146.12.128.1 to 146.12.191.254146.12.191.25516,382
52146.12.192.0/18146.12.192.1 to 146.12.255.254146.12.255.25516,382
53146.13.0.0/18146.13.0.1 to 146.13.63.254146.13.63.25516,382
54146.13.64.0/18146.13.64.1 to 146.13.127.254146.13.127.25516,382
55146.13.128.0/18146.13.128.1 to 146.13.191.254146.13.191.25516,382
56146.13.192.0/18146.13.192.1 to 146.13.255.254146.13.255.25516,382
57146.14.0.0/18146.14.0.1 to 146.14.63.254146.14.63.25516,382
58146.14.64.0/18146.14.64.1 to 146.14.127.254146.14.127.25516,382
59146.14.128.0/18146.14.128.1 to 146.14.191.254146.14.191.25516,382
60146.14.192.0/18146.14.192.1 to 146.14.255.254146.14.255.25516,382
61146.15.0.0/18146.15.0.1 to 146.15.63.254146.15.63.25516,382
62146.15.64.0/18146.15.64.1 to 146.15.127.254146.15.127.25516,382
63146.15.128.0/18146.15.128.1 to 146.15.191.254146.15.191.25516,382
64146.15.192.0/18146.15.192.1 to 146.15.255.254146.15.255.25516,382
65146.16.0.0/18146.16.0.1 to 146.16.63.254146.16.63.25516,382
66146.16.64.0/18146.16.64.1 to 146.16.127.254146.16.127.25516,382
67146.16.128.0/18146.16.128.1 to 146.16.191.254146.16.191.25516,382
68146.16.192.0/18146.16.192.1 to 146.16.255.254146.16.255.25516,382
69146.17.0.0/18146.17.0.1 to 146.17.63.254146.17.63.25516,382
70146.17.64.0/18146.17.64.1 to 146.17.127.254146.17.127.25516,382
71146.17.128.0/18146.17.128.1 to 146.17.191.254146.17.191.25516,382
72146.17.192.0/18146.17.192.1 to 146.17.255.254146.17.255.25516,382
73146.18.0.0/18146.18.0.1 to 146.18.63.254146.18.63.25516,382
74146.18.64.0/18146.18.64.1 to 146.18.127.254146.18.127.25516,382
75146.18.128.0/18146.18.128.1 to 146.18.191.254146.18.191.25516,382
76146.18.192.0/18146.18.192.1 to 146.18.255.254146.18.255.25516,382
77146.19.0.0/18146.19.0.1 to 146.19.63.254146.19.63.25516,382
78146.19.64.0/18146.19.64.1 to 146.19.127.254146.19.127.25516,382
79146.19.128.0/18146.19.128.1 to 146.19.191.254146.19.191.25516,382
80146.19.192.0/18146.19.192.1 to 146.19.255.254146.19.255.25516,382
81146.20.0.0/18146.20.0.1 to 146.20.63.254146.20.63.25516,382
82146.20.64.0/18146.20.64.1 to 146.20.127.254146.20.127.25516,382
83146.20.128.0/18146.20.128.1 to 146.20.191.254146.20.191.25516,382
84146.20.192.0/18146.20.192.1 to 146.20.255.254146.20.255.25516,382
85146.21.0.0/18146.21.0.1 to 146.21.63.254146.21.63.25516,382
86146.21.64.0/18146.21.64.1 to 146.21.127.254146.21.127.25516,382
87146.21.128.0/18146.21.128.1 to 146.21.191.254146.21.191.25516,382
88146.21.192.0/18146.21.192.1 to 146.21.255.254146.21.255.25516,382
89146.22.0.0/18146.22.0.1 to 146.22.63.254146.22.63.25516,382
90146.22.64.0/18146.22.64.1 to 146.22.127.254146.22.127.25516,382
91146.22.128.0/18146.22.128.1 to 146.22.191.254146.22.191.25516,382
92146.22.192.0/18146.22.192.1 to 146.22.255.254146.22.255.25516,382
93146.23.0.0/18146.23.0.1 to 146.23.63.254146.23.63.25516,382
94146.23.64.0/18146.23.64.1 to 146.23.127.254146.23.127.25516,382
95146.23.128.0/18146.23.128.1 to 146.23.191.254146.23.191.25516,382
96146.23.192.0/18146.23.192.1 to 146.23.255.254146.23.255.25516,382
97146.24.0.0/18146.24.0.1 to 146.24.63.254146.24.63.25516,382
98146.24.64.0/18146.24.64.1 to 146.24.127.254146.24.127.25516,382
99146.24.128.0/18146.24.128.1 to 146.24.191.254146.24.191.25516,382
100146.24.192.0/18146.24.192.1 to 146.24.255.254146.24.255.25516,382
101146.25.0.0/18146.25.0.1 to 146.25.63.254146.25.63.25516,382
102146.25.64.0/18146.25.64.1 to 146.25.127.254146.25.127.25516,382
103146.25.128.0/18146.25.128.1 to 146.25.191.254146.25.191.25516,382
104146.25.192.0/18146.25.192.1 to 146.25.255.254146.25.255.25516,382
105146.26.0.0/18146.26.0.1 to 146.26.63.254146.26.63.25516,382
106146.26.64.0/18146.26.64.1 to 146.26.127.254146.26.127.25516,382
107146.26.128.0/18146.26.128.1 to 146.26.191.254146.26.191.25516,382
108146.26.192.0/18146.26.192.1 to 146.26.255.254146.26.255.25516,382
109146.27.0.0/18146.27.0.1 to 146.27.63.254146.27.63.25516,382
110146.27.64.0/18146.27.64.1 to 146.27.127.254146.27.127.25516,382
111146.27.128.0/18146.27.128.1 to 146.27.191.254146.27.191.25516,382
112146.27.192.0/18146.27.192.1 to 146.27.255.254146.27.255.25516,382
113146.28.0.0/18146.28.0.1 to 146.28.63.254146.28.63.25516,382
114146.28.64.0/18146.28.64.1 to 146.28.127.254146.28.127.25516,382
115146.28.128.0/18146.28.128.1 to 146.28.191.254146.28.191.25516,382
116146.28.192.0/18146.28.192.1 to 146.28.255.254146.28.255.25516,382
117146.29.0.0/18146.29.0.1 to 146.29.63.254146.29.63.25516,382
118146.29.64.0/18146.29.64.1 to 146.29.127.254146.29.127.25516,382
119146.29.128.0/18146.29.128.1 to 146.29.191.254146.29.191.25516,382
120146.29.192.0/18146.29.192.1 to 146.29.255.254146.29.255.25516,382
121146.30.0.0/18146.30.0.1 to 146.30.63.254146.30.63.25516,382
122146.30.64.0/18146.30.64.1 to 146.30.127.254146.30.127.25516,382
123146.30.128.0/18146.30.128.1 to 146.30.191.254146.30.191.25516,382
124146.30.192.0/18146.30.192.1 to 146.30.255.254146.30.255.25516,382
125146.31.0.0/18146.31.0.1 to 146.31.63.254146.31.63.25516,382
126146.31.64.0/18146.31.64.1 to 146.31.127.254146.31.127.25516,382
127146.31.128.0/18146.31.128.1 to 146.31.191.254146.31.191.25516,382
128146.31.192.0/18146.31.192.1 to 146.31.255.254146.31.255.25516,382
129146.32.0.0/18146.32.0.1 to 146.32.63.254146.32.63.25516,382
130146.32.64.0/18146.32.64.1 to 146.32.127.254146.32.127.25516,382
131146.32.128.0/18146.32.128.1 to 146.32.191.254146.32.191.25516,382
132146.32.192.0/18146.32.192.1 to 146.32.255.254146.32.255.25516,382
133146.33.0.0/18146.33.0.1 to 146.33.63.254146.33.63.25516,382
134146.33.64.0/18146.33.64.1 to 146.33.127.254146.33.127.25516,382
135146.33.128.0/18146.33.128.1 to 146.33.191.254146.33.191.25516,382
136146.33.192.0/18146.33.192.1 to 146.33.255.254146.33.255.25516,382
137146.34.0.0/18146.34.0.1 to 146.34.63.254146.34.63.25516,382
138146.34.64.0/18146.34.64.1 to 146.34.127.254146.34.127.25516,382
139146.34.128.0/18146.34.128.1 to 146.34.191.254146.34.191.25516,382
140146.34.192.0/18146.34.192.1 to 146.34.255.254146.34.255.25516,382
141146.35.0.0/18146.35.0.1 to 146.35.63.254146.35.63.25516,382
142146.35.64.0/18146.35.64.1 to 146.35.127.254146.35.127.25516,382
143146.35.128.0/18146.35.128.1 to 146.35.191.254146.35.191.25516,382
144146.35.192.0/18146.35.192.1 to 146.35.255.254146.35.255.25516,382
145146.36.0.0/18146.36.0.1 to 146.36.63.254146.36.63.25516,382
146146.36.64.0/18146.36.64.1 to 146.36.127.254146.36.127.25516,382
147146.36.128.0/18146.36.128.1 to 146.36.191.254146.36.191.25516,382
148146.36.192.0/18146.36.192.1 to 146.36.255.254146.36.255.25516,382
149146.37.0.0/18146.37.0.1 to 146.37.63.254146.37.63.25516,382
150146.37.64.0/18146.37.64.1 to 146.37.127.254146.37.127.25516,382
151146.37.128.0/18146.37.128.1 to 146.37.191.254146.37.191.25516,382
152146.37.192.0/18146.37.192.1 to 146.37.255.254146.37.255.25516,382
153146.38.0.0/18146.38.0.1 to 146.38.63.254146.38.63.25516,382
154146.38.64.0/18146.38.64.1 to 146.38.127.254146.38.127.25516,382
155146.38.128.0/18146.38.128.1 to 146.38.191.254146.38.191.25516,382
156146.38.192.0/18146.38.192.1 to 146.38.255.254146.38.255.25516,382
157146.39.0.0/18146.39.0.1 to 146.39.63.254146.39.63.25516,382
158146.39.64.0/18146.39.64.1 to 146.39.127.254146.39.127.25516,382
159146.39.128.0/18146.39.128.1 to 146.39.191.254146.39.191.25516,382
160146.39.192.0/18146.39.192.1 to 146.39.255.254146.39.255.25516,382
161146.40.0.0/18146.40.0.1 to 146.40.63.254146.40.63.25516,382
162146.40.64.0/18146.40.64.1 to 146.40.127.254146.40.127.25516,382
163146.40.128.0/18146.40.128.1 to 146.40.191.254146.40.191.25516,382
164146.40.192.0/18146.40.192.1 to 146.40.255.254146.40.255.25516,382
165146.41.0.0/18146.41.0.1 to 146.41.63.254146.41.63.25516,382
166146.41.64.0/18146.41.64.1 to 146.41.127.254146.41.127.25516,382
167146.41.128.0/18146.41.128.1 to 146.41.191.254146.41.191.25516,382
168146.41.192.0/18146.41.192.1 to 146.41.255.254146.41.255.25516,382
169146.42.0.0/18146.42.0.1 to 146.42.63.254146.42.63.25516,382
170146.42.64.0/18146.42.64.1 to 146.42.127.254146.42.127.25516,382
171146.42.128.0/18146.42.128.1 to 146.42.191.254146.42.191.25516,382
172146.42.192.0/18146.42.192.1 to 146.42.255.254146.42.255.25516,382
173146.43.0.0/18146.43.0.1 to 146.43.63.254146.43.63.25516,382
174146.43.64.0/18146.43.64.1 to 146.43.127.254146.43.127.25516,382
175146.43.128.0/18146.43.128.1 to 146.43.191.254146.43.191.25516,382
176146.43.192.0/18146.43.192.1 to 146.43.255.254146.43.255.25516,382
177146.44.0.0/18146.44.0.1 to 146.44.63.254146.44.63.25516,382
178146.44.64.0/18146.44.64.1 to 146.44.127.254146.44.127.25516,382
179146.44.128.0/18146.44.128.1 to 146.44.191.254146.44.191.25516,382
180146.44.192.0/18146.44.192.1 to 146.44.255.254146.44.255.25516,382
181146.45.0.0/18146.45.0.1 to 146.45.63.254146.45.63.25516,382
182146.45.64.0/18146.45.64.1 to 146.45.127.254146.45.127.25516,382
183146.45.128.0/18146.45.128.1 to 146.45.191.254146.45.191.25516,382
184146.45.192.0/18146.45.192.1 to 146.45.255.254146.45.255.25516,382
185146.46.0.0/18146.46.0.1 to 146.46.63.254146.46.63.25516,382
186146.46.64.0/18146.46.64.1 to 146.46.127.254146.46.127.25516,382
187146.46.128.0/18146.46.128.1 to 146.46.191.254146.46.191.25516,382
188146.46.192.0/18146.46.192.1 to 146.46.255.254146.46.255.25516,382
189146.47.0.0/18146.47.0.1 to 146.47.63.254146.47.63.25516,382
190146.47.64.0/18146.47.64.1 to 146.47.127.254146.47.127.25516,382
191146.47.128.0/18146.47.128.1 to 146.47.191.254146.47.191.25516,382
192146.47.192.0/18146.47.192.1 to 146.47.255.254146.47.255.25516,382
193146.48.0.0/18146.48.0.1 to 146.48.63.254146.48.63.25516,382
194146.48.64.0/18146.48.64.1 to 146.48.127.254146.48.127.25516,382
195146.48.128.0/18146.48.128.1 to 146.48.191.254146.48.191.25516,382
196146.48.192.0/18146.48.192.1 to 146.48.255.254146.48.255.25516,382
197146.49.0.0/18146.49.0.1 to 146.49.63.254146.49.63.25516,382
198146.49.64.0/18146.49.64.1 to 146.49.127.254146.49.127.25516,382
199146.49.128.0/18146.49.128.1 to 146.49.191.254146.49.191.25516,382
200146.49.192.0/18146.49.192.1 to 146.49.255.254146.49.255.25516,382
201146.50.0.0/18146.50.0.1 to 146.50.63.254146.50.63.25516,382
202146.50.64.0/18146.50.64.1 to 146.50.127.254146.50.127.25516,382
203146.50.128.0/18146.50.128.1 to 146.50.191.254146.50.191.25516,382
204146.50.192.0/18146.50.192.1 to 146.50.255.254146.50.255.25516,382
205146.51.0.0/18146.51.0.1 to 146.51.63.254146.51.63.25516,382
206146.51.64.0/18146.51.64.1 to 146.51.127.254146.51.127.25516,382
207146.51.128.0/18146.51.128.1 to 146.51.191.254146.51.191.25516,382
208146.51.192.0/18146.51.192.1 to 146.51.255.254146.51.255.25516,382
209146.52.0.0/18146.52.0.1 to 146.52.63.254146.52.63.25516,382
210146.52.64.0/18146.52.64.1 to 146.52.127.254146.52.127.25516,382
211146.52.128.0/18146.52.128.1 to 146.52.191.254146.52.191.25516,382
212146.52.192.0/18146.52.192.1 to 146.52.255.254146.52.255.25516,382
213146.53.0.0/18146.53.0.1 to 146.53.63.254146.53.63.25516,382
214146.53.64.0/18146.53.64.1 to 146.53.127.254146.53.127.25516,382
215146.53.128.0/18146.53.128.1 to 146.53.191.254146.53.191.25516,382
216146.53.192.0/18146.53.192.1 to 146.53.255.254146.53.255.25516,382
217146.54.0.0/18146.54.0.1 to 146.54.63.254146.54.63.25516,382
218146.54.64.0/18146.54.64.1 to 146.54.127.254146.54.127.25516,382
219146.54.128.0/18146.54.128.1 to 146.54.191.254146.54.191.25516,382
220146.54.192.0/18146.54.192.1 to 146.54.255.254146.54.255.25516,382
221146.55.0.0/18146.55.0.1 to 146.55.63.254146.55.63.25516,382
222146.55.64.0/18146.55.64.1 to 146.55.127.254146.55.127.25516,382
223146.55.128.0/18146.55.128.1 to 146.55.191.254146.55.191.25516,382
224146.55.192.0/18146.55.192.1 to 146.55.255.254146.55.255.25516,382
225146.56.0.0/18146.56.0.1 to 146.56.63.254146.56.63.25516,382
226146.56.64.0/18146.56.64.1 to 146.56.127.254146.56.127.25516,382
227146.56.128.0/18146.56.128.1 to 146.56.191.254146.56.191.25516,382
228146.56.192.0/18146.56.192.1 to 146.56.255.254146.56.255.25516,382
229146.57.0.0/18146.57.0.1 to 146.57.63.254146.57.63.25516,382
230146.57.64.0/18146.57.64.1 to 146.57.127.254146.57.127.25516,382
231146.57.128.0/18146.57.128.1 to 146.57.191.254146.57.191.25516,382
232146.57.192.0/18146.57.192.1 to 146.57.255.254146.57.255.25516,382
233146.58.0.0/18146.58.0.1 to 146.58.63.254146.58.63.25516,382
234146.58.64.0/18146.58.64.1 to 146.58.127.254146.58.127.25516,382
235146.58.128.0/18146.58.128.1 to 146.58.191.254146.58.191.25516,382
236146.58.192.0/18146.58.192.1 to 146.58.255.254146.58.255.25516,382
237146.59.0.0/18146.59.0.1 to 146.59.63.254146.59.63.25516,382
238146.59.64.0/18146.59.64.1 to 146.59.127.254146.59.127.25516,382
239146.59.128.0/18146.59.128.1 to 146.59.191.254146.59.191.25516,382
240146.59.192.0/18146.59.192.1 to 146.59.255.254146.59.255.25516,382
241146.60.0.0/18146.60.0.1 to 146.60.63.254146.60.63.25516,382
242146.60.64.0/18146.60.64.1 to 146.60.127.254146.60.127.25516,382
243146.60.128.0/18146.60.128.1 to 146.60.191.254146.60.191.25516,382
244146.60.192.0/18146.60.192.1 to 146.60.255.254146.60.255.25516,382
245146.61.0.0/18146.61.0.1 to 146.61.63.254146.61.63.25516,382
246146.61.64.0/18146.61.64.1 to 146.61.127.254146.61.127.25516,382
247146.61.128.0/18146.61.128.1 to 146.61.191.254146.61.191.25516,382
248146.61.192.0/18146.61.192.1 to 146.61.255.254146.61.255.25516,382
249146.62.0.0/18146.62.0.1 to 146.62.63.254146.62.63.25516,382
250146.62.64.0/18146.62.64.1 to 146.62.127.254146.62.127.25516,382
251146.62.128.0/18146.62.128.1 to 146.62.191.254146.62.191.25516,382
252146.62.192.0/18146.62.192.1 to 146.62.255.254146.62.255.25516,382
253146.63.0.0/18146.63.0.1 to 146.63.63.254146.63.63.25516,382
254146.63.64.0/18146.63.64.1 to 146.63.127.254146.63.127.25516,382
255146.63.128.0/18146.63.128.1 to 146.63.191.254146.63.191.25516,382
256146.63.192.0/18146.63.192.1 to 146.63.255.254146.63.255.25516,382

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.