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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.

Network146.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
146.0.0.0
Broadcast address
147.255.255.255
First usable
146.0.0.1
Last usable
147.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
B (default /16)
As numbers
Hex 92000000 · Integer 2449473536 to 2483027967
Reverse DNS zones
146.in-addr.arpa
147.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10010010.00000000.00000000.00000000146.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10010010.00000000.00000000.00000000146.0.0.0
Broadcast10010011.11111111.11111111.11111111147.255.255.255
Split into smaller subnets/17
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

146.0.0.0/7 makes 1,024 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1146.0.0.0/17146.0.0.1 to 146.0.127.254146.0.127.25532,766
2146.0.128.0/17146.0.128.1 to 146.0.255.254146.0.255.25532,766
3146.1.0.0/17146.1.0.1 to 146.1.127.254146.1.127.25532,766
4146.1.128.0/17146.1.128.1 to 146.1.255.254146.1.255.25532,766
5146.2.0.0/17146.2.0.1 to 146.2.127.254146.2.127.25532,766
6146.2.128.0/17146.2.128.1 to 146.2.255.254146.2.255.25532,766
7146.3.0.0/17146.3.0.1 to 146.3.127.254146.3.127.25532,766
8146.3.128.0/17146.3.128.1 to 146.3.255.254146.3.255.25532,766
9146.4.0.0/17146.4.0.1 to 146.4.127.254146.4.127.25532,766
10146.4.128.0/17146.4.128.1 to 146.4.255.254146.4.255.25532,766
11146.5.0.0/17146.5.0.1 to 146.5.127.254146.5.127.25532,766
12146.5.128.0/17146.5.128.1 to 146.5.255.254146.5.255.25532,766
13146.6.0.0/17146.6.0.1 to 146.6.127.254146.6.127.25532,766
14146.6.128.0/17146.6.128.1 to 146.6.255.254146.6.255.25532,766
15146.7.0.0/17146.7.0.1 to 146.7.127.254146.7.127.25532,766
16146.7.128.0/17146.7.128.1 to 146.7.255.254146.7.255.25532,766
17146.8.0.0/17146.8.0.1 to 146.8.127.254146.8.127.25532,766
18146.8.128.0/17146.8.128.1 to 146.8.255.254146.8.255.25532,766
19146.9.0.0/17146.9.0.1 to 146.9.127.254146.9.127.25532,766
20146.9.128.0/17146.9.128.1 to 146.9.255.254146.9.255.25532,766
21146.10.0.0/17146.10.0.1 to 146.10.127.254146.10.127.25532,766
22146.10.128.0/17146.10.128.1 to 146.10.255.254146.10.255.25532,766
23146.11.0.0/17146.11.0.1 to 146.11.127.254146.11.127.25532,766
24146.11.128.0/17146.11.128.1 to 146.11.255.254146.11.255.25532,766
25146.12.0.0/17146.12.0.1 to 146.12.127.254146.12.127.25532,766
26146.12.128.0/17146.12.128.1 to 146.12.255.254146.12.255.25532,766
27146.13.0.0/17146.13.0.1 to 146.13.127.254146.13.127.25532,766
28146.13.128.0/17146.13.128.1 to 146.13.255.254146.13.255.25532,766
29146.14.0.0/17146.14.0.1 to 146.14.127.254146.14.127.25532,766
30146.14.128.0/17146.14.128.1 to 146.14.255.254146.14.255.25532,766
31146.15.0.0/17146.15.0.1 to 146.15.127.254146.15.127.25532,766
32146.15.128.0/17146.15.128.1 to 146.15.255.254146.15.255.25532,766
33146.16.0.0/17146.16.0.1 to 146.16.127.254146.16.127.25532,766
34146.16.128.0/17146.16.128.1 to 146.16.255.254146.16.255.25532,766
35146.17.0.0/17146.17.0.1 to 146.17.127.254146.17.127.25532,766
36146.17.128.0/17146.17.128.1 to 146.17.255.254146.17.255.25532,766
37146.18.0.0/17146.18.0.1 to 146.18.127.254146.18.127.25532,766
38146.18.128.0/17146.18.128.1 to 146.18.255.254146.18.255.25532,766
39146.19.0.0/17146.19.0.1 to 146.19.127.254146.19.127.25532,766
40146.19.128.0/17146.19.128.1 to 146.19.255.254146.19.255.25532,766
41146.20.0.0/17146.20.0.1 to 146.20.127.254146.20.127.25532,766
42146.20.128.0/17146.20.128.1 to 146.20.255.254146.20.255.25532,766
43146.21.0.0/17146.21.0.1 to 146.21.127.254146.21.127.25532,766
44146.21.128.0/17146.21.128.1 to 146.21.255.254146.21.255.25532,766
45146.22.0.0/17146.22.0.1 to 146.22.127.254146.22.127.25532,766
46146.22.128.0/17146.22.128.1 to 146.22.255.254146.22.255.25532,766
47146.23.0.0/17146.23.0.1 to 146.23.127.254146.23.127.25532,766
48146.23.128.0/17146.23.128.1 to 146.23.255.254146.23.255.25532,766
49146.24.0.0/17146.24.0.1 to 146.24.127.254146.24.127.25532,766
50146.24.128.0/17146.24.128.1 to 146.24.255.254146.24.255.25532,766
51146.25.0.0/17146.25.0.1 to 146.25.127.254146.25.127.25532,766
52146.25.128.0/17146.25.128.1 to 146.25.255.254146.25.255.25532,766
53146.26.0.0/17146.26.0.1 to 146.26.127.254146.26.127.25532,766
54146.26.128.0/17146.26.128.1 to 146.26.255.254146.26.255.25532,766
55146.27.0.0/17146.27.0.1 to 146.27.127.254146.27.127.25532,766
56146.27.128.0/17146.27.128.1 to 146.27.255.254146.27.255.25532,766
57146.28.0.0/17146.28.0.1 to 146.28.127.254146.28.127.25532,766
58146.28.128.0/17146.28.128.1 to 146.28.255.254146.28.255.25532,766
59146.29.0.0/17146.29.0.1 to 146.29.127.254146.29.127.25532,766
60146.29.128.0/17146.29.128.1 to 146.29.255.254146.29.255.25532,766
61146.30.0.0/17146.30.0.1 to 146.30.127.254146.30.127.25532,766
62146.30.128.0/17146.30.128.1 to 146.30.255.254146.30.255.25532,766
63146.31.0.0/17146.31.0.1 to 146.31.127.254146.31.127.25532,766
64146.31.128.0/17146.31.128.1 to 146.31.255.254146.31.255.25532,766
65146.32.0.0/17146.32.0.1 to 146.32.127.254146.32.127.25532,766
66146.32.128.0/17146.32.128.1 to 146.32.255.254146.32.255.25532,766
67146.33.0.0/17146.33.0.1 to 146.33.127.254146.33.127.25532,766
68146.33.128.0/17146.33.128.1 to 146.33.255.254146.33.255.25532,766
69146.34.0.0/17146.34.0.1 to 146.34.127.254146.34.127.25532,766
70146.34.128.0/17146.34.128.1 to 146.34.255.254146.34.255.25532,766
71146.35.0.0/17146.35.0.1 to 146.35.127.254146.35.127.25532,766
72146.35.128.0/17146.35.128.1 to 146.35.255.254146.35.255.25532,766
73146.36.0.0/17146.36.0.1 to 146.36.127.254146.36.127.25532,766
74146.36.128.0/17146.36.128.1 to 146.36.255.254146.36.255.25532,766
75146.37.0.0/17146.37.0.1 to 146.37.127.254146.37.127.25532,766
76146.37.128.0/17146.37.128.1 to 146.37.255.254146.37.255.25532,766
77146.38.0.0/17146.38.0.1 to 146.38.127.254146.38.127.25532,766
78146.38.128.0/17146.38.128.1 to 146.38.255.254146.38.255.25532,766
79146.39.0.0/17146.39.0.1 to 146.39.127.254146.39.127.25532,766
80146.39.128.0/17146.39.128.1 to 146.39.255.254146.39.255.25532,766
81146.40.0.0/17146.40.0.1 to 146.40.127.254146.40.127.25532,766
82146.40.128.0/17146.40.128.1 to 146.40.255.254146.40.255.25532,766
83146.41.0.0/17146.41.0.1 to 146.41.127.254146.41.127.25532,766
84146.41.128.0/17146.41.128.1 to 146.41.255.254146.41.255.25532,766
85146.42.0.0/17146.42.0.1 to 146.42.127.254146.42.127.25532,766
86146.42.128.0/17146.42.128.1 to 146.42.255.254146.42.255.25532,766
87146.43.0.0/17146.43.0.1 to 146.43.127.254146.43.127.25532,766
88146.43.128.0/17146.43.128.1 to 146.43.255.254146.43.255.25532,766
89146.44.0.0/17146.44.0.1 to 146.44.127.254146.44.127.25532,766
90146.44.128.0/17146.44.128.1 to 146.44.255.254146.44.255.25532,766
91146.45.0.0/17146.45.0.1 to 146.45.127.254146.45.127.25532,766
92146.45.128.0/17146.45.128.1 to 146.45.255.254146.45.255.25532,766
93146.46.0.0/17146.46.0.1 to 146.46.127.254146.46.127.25532,766
94146.46.128.0/17146.46.128.1 to 146.46.255.254146.46.255.25532,766
95146.47.0.0/17146.47.0.1 to 146.47.127.254146.47.127.25532,766
96146.47.128.0/17146.47.128.1 to 146.47.255.254146.47.255.25532,766
97146.48.0.0/17146.48.0.1 to 146.48.127.254146.48.127.25532,766
98146.48.128.0/17146.48.128.1 to 146.48.255.254146.48.255.25532,766
99146.49.0.0/17146.49.0.1 to 146.49.127.254146.49.127.25532,766
100146.49.128.0/17146.49.128.1 to 146.49.255.254146.49.255.25532,766
101146.50.0.0/17146.50.0.1 to 146.50.127.254146.50.127.25532,766
102146.50.128.0/17146.50.128.1 to 146.50.255.254146.50.255.25532,766
103146.51.0.0/17146.51.0.1 to 146.51.127.254146.51.127.25532,766
104146.51.128.0/17146.51.128.1 to 146.51.255.254146.51.255.25532,766
105146.52.0.0/17146.52.0.1 to 146.52.127.254146.52.127.25532,766
106146.52.128.0/17146.52.128.1 to 146.52.255.254146.52.255.25532,766
107146.53.0.0/17146.53.0.1 to 146.53.127.254146.53.127.25532,766
108146.53.128.0/17146.53.128.1 to 146.53.255.254146.53.255.25532,766
109146.54.0.0/17146.54.0.1 to 146.54.127.254146.54.127.25532,766
110146.54.128.0/17146.54.128.1 to 146.54.255.254146.54.255.25532,766
111146.55.0.0/17146.55.0.1 to 146.55.127.254146.55.127.25532,766
112146.55.128.0/17146.55.128.1 to 146.55.255.254146.55.255.25532,766
113146.56.0.0/17146.56.0.1 to 146.56.127.254146.56.127.25532,766
114146.56.128.0/17146.56.128.1 to 146.56.255.254146.56.255.25532,766
115146.57.0.0/17146.57.0.1 to 146.57.127.254146.57.127.25532,766
116146.57.128.0/17146.57.128.1 to 146.57.255.254146.57.255.25532,766
117146.58.0.0/17146.58.0.1 to 146.58.127.254146.58.127.25532,766
118146.58.128.0/17146.58.128.1 to 146.58.255.254146.58.255.25532,766
119146.59.0.0/17146.59.0.1 to 146.59.127.254146.59.127.25532,766
120146.59.128.0/17146.59.128.1 to 146.59.255.254146.59.255.25532,766
121146.60.0.0/17146.60.0.1 to 146.60.127.254146.60.127.25532,766
122146.60.128.0/17146.60.128.1 to 146.60.255.254146.60.255.25532,766
123146.61.0.0/17146.61.0.1 to 146.61.127.254146.61.127.25532,766
124146.61.128.0/17146.61.128.1 to 146.61.255.254146.61.255.25532,766
125146.62.0.0/17146.62.0.1 to 146.62.127.254146.62.127.25532,766
126146.62.128.0/17146.62.128.1 to 146.62.255.254146.62.255.25532,766
127146.63.0.0/17146.63.0.1 to 146.63.127.254146.63.127.25532,766
128146.63.128.0/17146.63.128.1 to 146.63.255.254146.63.255.25532,766
129146.64.0.0/17146.64.0.1 to 146.64.127.254146.64.127.25532,766
130146.64.128.0/17146.64.128.1 to 146.64.255.254146.64.255.25532,766
131146.65.0.0/17146.65.0.1 to 146.65.127.254146.65.127.25532,766
132146.65.128.0/17146.65.128.1 to 146.65.255.254146.65.255.25532,766
133146.66.0.0/17146.66.0.1 to 146.66.127.254146.66.127.25532,766
134146.66.128.0/17146.66.128.1 to 146.66.255.254146.66.255.25532,766
135146.67.0.0/17146.67.0.1 to 146.67.127.254146.67.127.25532,766
136146.67.128.0/17146.67.128.1 to 146.67.255.254146.67.255.25532,766
137146.68.0.0/17146.68.0.1 to 146.68.127.254146.68.127.25532,766
138146.68.128.0/17146.68.128.1 to 146.68.255.254146.68.255.25532,766
139146.69.0.0/17146.69.0.1 to 146.69.127.254146.69.127.25532,766
140146.69.128.0/17146.69.128.1 to 146.69.255.254146.69.255.25532,766
141146.70.0.0/17146.70.0.1 to 146.70.127.254146.70.127.25532,766
142146.70.128.0/17146.70.128.1 to 146.70.255.254146.70.255.25532,766
143146.71.0.0/17146.71.0.1 to 146.71.127.254146.71.127.25532,766
144146.71.128.0/17146.71.128.1 to 146.71.255.254146.71.255.25532,766
145146.72.0.0/17146.72.0.1 to 146.72.127.254146.72.127.25532,766
146146.72.128.0/17146.72.128.1 to 146.72.255.254146.72.255.25532,766
147146.73.0.0/17146.73.0.1 to 146.73.127.254146.73.127.25532,766
148146.73.128.0/17146.73.128.1 to 146.73.255.254146.73.255.25532,766
149146.74.0.0/17146.74.0.1 to 146.74.127.254146.74.127.25532,766
150146.74.128.0/17146.74.128.1 to 146.74.255.254146.74.255.25532,766
151146.75.0.0/17146.75.0.1 to 146.75.127.254146.75.127.25532,766
152146.75.128.0/17146.75.128.1 to 146.75.255.254146.75.255.25532,766
153146.76.0.0/17146.76.0.1 to 146.76.127.254146.76.127.25532,766
154146.76.128.0/17146.76.128.1 to 146.76.255.254146.76.255.25532,766
155146.77.0.0/17146.77.0.1 to 146.77.127.254146.77.127.25532,766
156146.77.128.0/17146.77.128.1 to 146.77.255.254146.77.255.25532,766
157146.78.0.0/17146.78.0.1 to 146.78.127.254146.78.127.25532,766
158146.78.128.0/17146.78.128.1 to 146.78.255.254146.78.255.25532,766
159146.79.0.0/17146.79.0.1 to 146.79.127.254146.79.127.25532,766
160146.79.128.0/17146.79.128.1 to 146.79.255.254146.79.255.25532,766
161146.80.0.0/17146.80.0.1 to 146.80.127.254146.80.127.25532,766
162146.80.128.0/17146.80.128.1 to 146.80.255.254146.80.255.25532,766
163146.81.0.0/17146.81.0.1 to 146.81.127.254146.81.127.25532,766
164146.81.128.0/17146.81.128.1 to 146.81.255.254146.81.255.25532,766
165146.82.0.0/17146.82.0.1 to 146.82.127.254146.82.127.25532,766
166146.82.128.0/17146.82.128.1 to 146.82.255.254146.82.255.25532,766
167146.83.0.0/17146.83.0.1 to 146.83.127.254146.83.127.25532,766
168146.83.128.0/17146.83.128.1 to 146.83.255.254146.83.255.25532,766
169146.84.0.0/17146.84.0.1 to 146.84.127.254146.84.127.25532,766
170146.84.128.0/17146.84.128.1 to 146.84.255.254146.84.255.25532,766
171146.85.0.0/17146.85.0.1 to 146.85.127.254146.85.127.25532,766
172146.85.128.0/17146.85.128.1 to 146.85.255.254146.85.255.25532,766
173146.86.0.0/17146.86.0.1 to 146.86.127.254146.86.127.25532,766
174146.86.128.0/17146.86.128.1 to 146.86.255.254146.86.255.25532,766
175146.87.0.0/17146.87.0.1 to 146.87.127.254146.87.127.25532,766
176146.87.128.0/17146.87.128.1 to 146.87.255.254146.87.255.25532,766
177146.88.0.0/17146.88.0.1 to 146.88.127.254146.88.127.25532,766
178146.88.128.0/17146.88.128.1 to 146.88.255.254146.88.255.25532,766
179146.89.0.0/17146.89.0.1 to 146.89.127.254146.89.127.25532,766
180146.89.128.0/17146.89.128.1 to 146.89.255.254146.89.255.25532,766
181146.90.0.0/17146.90.0.1 to 146.90.127.254146.90.127.25532,766
182146.90.128.0/17146.90.128.1 to 146.90.255.254146.90.255.25532,766
183146.91.0.0/17146.91.0.1 to 146.91.127.254146.91.127.25532,766
184146.91.128.0/17146.91.128.1 to 146.91.255.254146.91.255.25532,766
185146.92.0.0/17146.92.0.1 to 146.92.127.254146.92.127.25532,766
186146.92.128.0/17146.92.128.1 to 146.92.255.254146.92.255.25532,766
187146.93.0.0/17146.93.0.1 to 146.93.127.254146.93.127.25532,766
188146.93.128.0/17146.93.128.1 to 146.93.255.254146.93.255.25532,766
189146.94.0.0/17146.94.0.1 to 146.94.127.254146.94.127.25532,766
190146.94.128.0/17146.94.128.1 to 146.94.255.254146.94.255.25532,766
191146.95.0.0/17146.95.0.1 to 146.95.127.254146.95.127.25532,766
192146.95.128.0/17146.95.128.1 to 146.95.255.254146.95.255.25532,766
193146.96.0.0/17146.96.0.1 to 146.96.127.254146.96.127.25532,766
194146.96.128.0/17146.96.128.1 to 146.96.255.254146.96.255.25532,766
195146.97.0.0/17146.97.0.1 to 146.97.127.254146.97.127.25532,766
196146.97.128.0/17146.97.128.1 to 146.97.255.254146.97.255.25532,766
197146.98.0.0/17146.98.0.1 to 146.98.127.254146.98.127.25532,766
198146.98.128.0/17146.98.128.1 to 146.98.255.254146.98.255.25532,766
199146.99.0.0/17146.99.0.1 to 146.99.127.254146.99.127.25532,766
200146.99.128.0/17146.99.128.1 to 146.99.255.254146.99.255.25532,766
201146.100.0.0/17146.100.0.1 to 146.100.127.254146.100.127.25532,766
202146.100.128.0/17146.100.128.1 to 146.100.255.254146.100.255.25532,766
203146.101.0.0/17146.101.0.1 to 146.101.127.254146.101.127.25532,766
204146.101.128.0/17146.101.128.1 to 146.101.255.254146.101.255.25532,766
205146.102.0.0/17146.102.0.1 to 146.102.127.254146.102.127.25532,766
206146.102.128.0/17146.102.128.1 to 146.102.255.254146.102.255.25532,766
207146.103.0.0/17146.103.0.1 to 146.103.127.254146.103.127.25532,766
208146.103.128.0/17146.103.128.1 to 146.103.255.254146.103.255.25532,766
209146.104.0.0/17146.104.0.1 to 146.104.127.254146.104.127.25532,766
210146.104.128.0/17146.104.128.1 to 146.104.255.254146.104.255.25532,766
211146.105.0.0/17146.105.0.1 to 146.105.127.254146.105.127.25532,766
212146.105.128.0/17146.105.128.1 to 146.105.255.254146.105.255.25532,766
213146.106.0.0/17146.106.0.1 to 146.106.127.254146.106.127.25532,766
214146.106.128.0/17146.106.128.1 to 146.106.255.254146.106.255.25532,766
215146.107.0.0/17146.107.0.1 to 146.107.127.254146.107.127.25532,766
216146.107.128.0/17146.107.128.1 to 146.107.255.254146.107.255.25532,766
217146.108.0.0/17146.108.0.1 to 146.108.127.254146.108.127.25532,766
218146.108.128.0/17146.108.128.1 to 146.108.255.254146.108.255.25532,766
219146.109.0.0/17146.109.0.1 to 146.109.127.254146.109.127.25532,766
220146.109.128.0/17146.109.128.1 to 146.109.255.254146.109.255.25532,766
221146.110.0.0/17146.110.0.1 to 146.110.127.254146.110.127.25532,766
222146.110.128.0/17146.110.128.1 to 146.110.255.254146.110.255.25532,766
223146.111.0.0/17146.111.0.1 to 146.111.127.254146.111.127.25532,766
224146.111.128.0/17146.111.128.1 to 146.111.255.254146.111.255.25532,766
225146.112.0.0/17146.112.0.1 to 146.112.127.254146.112.127.25532,766
226146.112.128.0/17146.112.128.1 to 146.112.255.254146.112.255.25532,766
227146.113.0.0/17146.113.0.1 to 146.113.127.254146.113.127.25532,766
228146.113.128.0/17146.113.128.1 to 146.113.255.254146.113.255.25532,766
229146.114.0.0/17146.114.0.1 to 146.114.127.254146.114.127.25532,766
230146.114.128.0/17146.114.128.1 to 146.114.255.254146.114.255.25532,766
231146.115.0.0/17146.115.0.1 to 146.115.127.254146.115.127.25532,766
232146.115.128.0/17146.115.128.1 to 146.115.255.254146.115.255.25532,766
233146.116.0.0/17146.116.0.1 to 146.116.127.254146.116.127.25532,766
234146.116.128.0/17146.116.128.1 to 146.116.255.254146.116.255.25532,766
235146.117.0.0/17146.117.0.1 to 146.117.127.254146.117.127.25532,766
236146.117.128.0/17146.117.128.1 to 146.117.255.254146.117.255.25532,766
237146.118.0.0/17146.118.0.1 to 146.118.127.254146.118.127.25532,766
238146.118.128.0/17146.118.128.1 to 146.118.255.254146.118.255.25532,766
239146.119.0.0/17146.119.0.1 to 146.119.127.254146.119.127.25532,766
240146.119.128.0/17146.119.128.1 to 146.119.255.254146.119.255.25532,766
241146.120.0.0/17146.120.0.1 to 146.120.127.254146.120.127.25532,766
242146.120.128.0/17146.120.128.1 to 146.120.255.254146.120.255.25532,766
243146.121.0.0/17146.121.0.1 to 146.121.127.254146.121.127.25532,766
244146.121.128.0/17146.121.128.1 to 146.121.255.254146.121.255.25532,766
245146.122.0.0/17146.122.0.1 to 146.122.127.254146.122.127.25532,766
246146.122.128.0/17146.122.128.1 to 146.122.255.254146.122.255.25532,766
247146.123.0.0/17146.123.0.1 to 146.123.127.254146.123.127.25532,766
248146.123.128.0/17146.123.128.1 to 146.123.255.254146.123.255.25532,766
249146.124.0.0/17146.124.0.1 to 146.124.127.254146.124.127.25532,766
250146.124.128.0/17146.124.128.1 to 146.124.255.254146.124.255.25532,766
251146.125.0.0/17146.125.0.1 to 146.125.127.254146.125.127.25532,766
252146.125.128.0/17146.125.128.1 to 146.125.255.254146.125.255.25532,766
253146.126.0.0/17146.126.0.1 to 146.126.127.254146.126.127.25532,766
254146.126.128.0/17146.126.128.1 to 146.126.255.254146.126.255.25532,766
255146.127.0.0/17146.127.0.1 to 146.127.127.254146.127.127.25532,766
256146.127.128.0/17146.127.128.1 to 146.127.255.254146.127.255.25532,766

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.