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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.

Network162.40.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
162.40.0.0
Broadcast address
162.47.255.255
First usable
162.40.0.1
Last usable
162.47.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
B (default /16)
As numbers
Hex A2280000 · Integer 2720530432 to 2721054719
Reverse DNS zones
40.162.in-addr.arpa
41.162.in-addr.arpa
42.162.in-addr.arpa
43.162.in-addr.arpa
44.162.in-addr.arpa
45.162.in-addr.arpa
46.162.in-addr.arpa
47.162.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10100010.00101000.00000000.00000000162.40.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network10100010.00101000.00000000.00000000162.40.0.0
Broadcast10100010.00101111.11111111.11111111162.47.255.255
Split into smaller subnets/25
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

162.40.0.0/13 makes 4,096 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1162.40.0.0/25162.40.0.1 to 162.40.0.126162.40.0.127126
2162.40.0.128/25162.40.0.129 to 162.40.0.254162.40.0.255126
3162.40.1.0/25162.40.1.1 to 162.40.1.126162.40.1.127126
4162.40.1.128/25162.40.1.129 to 162.40.1.254162.40.1.255126
5162.40.2.0/25162.40.2.1 to 162.40.2.126162.40.2.127126
6162.40.2.128/25162.40.2.129 to 162.40.2.254162.40.2.255126
7162.40.3.0/25162.40.3.1 to 162.40.3.126162.40.3.127126
8162.40.3.128/25162.40.3.129 to 162.40.3.254162.40.3.255126
9162.40.4.0/25162.40.4.1 to 162.40.4.126162.40.4.127126
10162.40.4.128/25162.40.4.129 to 162.40.4.254162.40.4.255126
11162.40.5.0/25162.40.5.1 to 162.40.5.126162.40.5.127126
12162.40.5.128/25162.40.5.129 to 162.40.5.254162.40.5.255126
13162.40.6.0/25162.40.6.1 to 162.40.6.126162.40.6.127126
14162.40.6.128/25162.40.6.129 to 162.40.6.254162.40.6.255126
15162.40.7.0/25162.40.7.1 to 162.40.7.126162.40.7.127126
16162.40.7.128/25162.40.7.129 to 162.40.7.254162.40.7.255126
17162.40.8.0/25162.40.8.1 to 162.40.8.126162.40.8.127126
18162.40.8.128/25162.40.8.129 to 162.40.8.254162.40.8.255126
19162.40.9.0/25162.40.9.1 to 162.40.9.126162.40.9.127126
20162.40.9.128/25162.40.9.129 to 162.40.9.254162.40.9.255126
21162.40.10.0/25162.40.10.1 to 162.40.10.126162.40.10.127126
22162.40.10.128/25162.40.10.129 to 162.40.10.254162.40.10.255126
23162.40.11.0/25162.40.11.1 to 162.40.11.126162.40.11.127126
24162.40.11.128/25162.40.11.129 to 162.40.11.254162.40.11.255126
25162.40.12.0/25162.40.12.1 to 162.40.12.126162.40.12.127126
26162.40.12.128/25162.40.12.129 to 162.40.12.254162.40.12.255126
27162.40.13.0/25162.40.13.1 to 162.40.13.126162.40.13.127126
28162.40.13.128/25162.40.13.129 to 162.40.13.254162.40.13.255126
29162.40.14.0/25162.40.14.1 to 162.40.14.126162.40.14.127126
30162.40.14.128/25162.40.14.129 to 162.40.14.254162.40.14.255126
31162.40.15.0/25162.40.15.1 to 162.40.15.126162.40.15.127126
32162.40.15.128/25162.40.15.129 to 162.40.15.254162.40.15.255126
33162.40.16.0/25162.40.16.1 to 162.40.16.126162.40.16.127126
34162.40.16.128/25162.40.16.129 to 162.40.16.254162.40.16.255126
35162.40.17.0/25162.40.17.1 to 162.40.17.126162.40.17.127126
36162.40.17.128/25162.40.17.129 to 162.40.17.254162.40.17.255126
37162.40.18.0/25162.40.18.1 to 162.40.18.126162.40.18.127126
38162.40.18.128/25162.40.18.129 to 162.40.18.254162.40.18.255126
39162.40.19.0/25162.40.19.1 to 162.40.19.126162.40.19.127126
40162.40.19.128/25162.40.19.129 to 162.40.19.254162.40.19.255126
41162.40.20.0/25162.40.20.1 to 162.40.20.126162.40.20.127126
42162.40.20.128/25162.40.20.129 to 162.40.20.254162.40.20.255126
43162.40.21.0/25162.40.21.1 to 162.40.21.126162.40.21.127126
44162.40.21.128/25162.40.21.129 to 162.40.21.254162.40.21.255126
45162.40.22.0/25162.40.22.1 to 162.40.22.126162.40.22.127126
46162.40.22.128/25162.40.22.129 to 162.40.22.254162.40.22.255126
47162.40.23.0/25162.40.23.1 to 162.40.23.126162.40.23.127126
48162.40.23.128/25162.40.23.129 to 162.40.23.254162.40.23.255126
49162.40.24.0/25162.40.24.1 to 162.40.24.126162.40.24.127126
50162.40.24.128/25162.40.24.129 to 162.40.24.254162.40.24.255126
51162.40.25.0/25162.40.25.1 to 162.40.25.126162.40.25.127126
52162.40.25.128/25162.40.25.129 to 162.40.25.254162.40.25.255126
53162.40.26.0/25162.40.26.1 to 162.40.26.126162.40.26.127126
54162.40.26.128/25162.40.26.129 to 162.40.26.254162.40.26.255126
55162.40.27.0/25162.40.27.1 to 162.40.27.126162.40.27.127126
56162.40.27.128/25162.40.27.129 to 162.40.27.254162.40.27.255126
57162.40.28.0/25162.40.28.1 to 162.40.28.126162.40.28.127126
58162.40.28.128/25162.40.28.129 to 162.40.28.254162.40.28.255126
59162.40.29.0/25162.40.29.1 to 162.40.29.126162.40.29.127126
60162.40.29.128/25162.40.29.129 to 162.40.29.254162.40.29.255126
61162.40.30.0/25162.40.30.1 to 162.40.30.126162.40.30.127126
62162.40.30.128/25162.40.30.129 to 162.40.30.254162.40.30.255126
63162.40.31.0/25162.40.31.1 to 162.40.31.126162.40.31.127126
64162.40.31.128/25162.40.31.129 to 162.40.31.254162.40.31.255126
65162.40.32.0/25162.40.32.1 to 162.40.32.126162.40.32.127126
66162.40.32.128/25162.40.32.129 to 162.40.32.254162.40.32.255126
67162.40.33.0/25162.40.33.1 to 162.40.33.126162.40.33.127126
68162.40.33.128/25162.40.33.129 to 162.40.33.254162.40.33.255126
69162.40.34.0/25162.40.34.1 to 162.40.34.126162.40.34.127126
70162.40.34.128/25162.40.34.129 to 162.40.34.254162.40.34.255126
71162.40.35.0/25162.40.35.1 to 162.40.35.126162.40.35.127126
72162.40.35.128/25162.40.35.129 to 162.40.35.254162.40.35.255126
73162.40.36.0/25162.40.36.1 to 162.40.36.126162.40.36.127126
74162.40.36.128/25162.40.36.129 to 162.40.36.254162.40.36.255126
75162.40.37.0/25162.40.37.1 to 162.40.37.126162.40.37.127126
76162.40.37.128/25162.40.37.129 to 162.40.37.254162.40.37.255126
77162.40.38.0/25162.40.38.1 to 162.40.38.126162.40.38.127126
78162.40.38.128/25162.40.38.129 to 162.40.38.254162.40.38.255126
79162.40.39.0/25162.40.39.1 to 162.40.39.126162.40.39.127126
80162.40.39.128/25162.40.39.129 to 162.40.39.254162.40.39.255126
81162.40.40.0/25162.40.40.1 to 162.40.40.126162.40.40.127126
82162.40.40.128/25162.40.40.129 to 162.40.40.254162.40.40.255126
83162.40.41.0/25162.40.41.1 to 162.40.41.126162.40.41.127126
84162.40.41.128/25162.40.41.129 to 162.40.41.254162.40.41.255126
85162.40.42.0/25162.40.42.1 to 162.40.42.126162.40.42.127126
86162.40.42.128/25162.40.42.129 to 162.40.42.254162.40.42.255126
87162.40.43.0/25162.40.43.1 to 162.40.43.126162.40.43.127126
88162.40.43.128/25162.40.43.129 to 162.40.43.254162.40.43.255126
89162.40.44.0/25162.40.44.1 to 162.40.44.126162.40.44.127126
90162.40.44.128/25162.40.44.129 to 162.40.44.254162.40.44.255126
91162.40.45.0/25162.40.45.1 to 162.40.45.126162.40.45.127126
92162.40.45.128/25162.40.45.129 to 162.40.45.254162.40.45.255126
93162.40.46.0/25162.40.46.1 to 162.40.46.126162.40.46.127126
94162.40.46.128/25162.40.46.129 to 162.40.46.254162.40.46.255126
95162.40.47.0/25162.40.47.1 to 162.40.47.126162.40.47.127126
96162.40.47.128/25162.40.47.129 to 162.40.47.254162.40.47.255126
97162.40.48.0/25162.40.48.1 to 162.40.48.126162.40.48.127126
98162.40.48.128/25162.40.48.129 to 162.40.48.254162.40.48.255126
99162.40.49.0/25162.40.49.1 to 162.40.49.126162.40.49.127126
100162.40.49.128/25162.40.49.129 to 162.40.49.254162.40.49.255126
101162.40.50.0/25162.40.50.1 to 162.40.50.126162.40.50.127126
102162.40.50.128/25162.40.50.129 to 162.40.50.254162.40.50.255126
103162.40.51.0/25162.40.51.1 to 162.40.51.126162.40.51.127126
104162.40.51.128/25162.40.51.129 to 162.40.51.254162.40.51.255126
105162.40.52.0/25162.40.52.1 to 162.40.52.126162.40.52.127126
106162.40.52.128/25162.40.52.129 to 162.40.52.254162.40.52.255126
107162.40.53.0/25162.40.53.1 to 162.40.53.126162.40.53.127126
108162.40.53.128/25162.40.53.129 to 162.40.53.254162.40.53.255126
109162.40.54.0/25162.40.54.1 to 162.40.54.126162.40.54.127126
110162.40.54.128/25162.40.54.129 to 162.40.54.254162.40.54.255126
111162.40.55.0/25162.40.55.1 to 162.40.55.126162.40.55.127126
112162.40.55.128/25162.40.55.129 to 162.40.55.254162.40.55.255126
113162.40.56.0/25162.40.56.1 to 162.40.56.126162.40.56.127126
114162.40.56.128/25162.40.56.129 to 162.40.56.254162.40.56.255126
115162.40.57.0/25162.40.57.1 to 162.40.57.126162.40.57.127126
116162.40.57.128/25162.40.57.129 to 162.40.57.254162.40.57.255126
117162.40.58.0/25162.40.58.1 to 162.40.58.126162.40.58.127126
118162.40.58.128/25162.40.58.129 to 162.40.58.254162.40.58.255126
119162.40.59.0/25162.40.59.1 to 162.40.59.126162.40.59.127126
120162.40.59.128/25162.40.59.129 to 162.40.59.254162.40.59.255126
121162.40.60.0/25162.40.60.1 to 162.40.60.126162.40.60.127126
122162.40.60.128/25162.40.60.129 to 162.40.60.254162.40.60.255126
123162.40.61.0/25162.40.61.1 to 162.40.61.126162.40.61.127126
124162.40.61.128/25162.40.61.129 to 162.40.61.254162.40.61.255126
125162.40.62.0/25162.40.62.1 to 162.40.62.126162.40.62.127126
126162.40.62.128/25162.40.62.129 to 162.40.62.254162.40.62.255126
127162.40.63.0/25162.40.63.1 to 162.40.63.126162.40.63.127126
128162.40.63.128/25162.40.63.129 to 162.40.63.254162.40.63.255126
129162.40.64.0/25162.40.64.1 to 162.40.64.126162.40.64.127126
130162.40.64.128/25162.40.64.129 to 162.40.64.254162.40.64.255126
131162.40.65.0/25162.40.65.1 to 162.40.65.126162.40.65.127126
132162.40.65.128/25162.40.65.129 to 162.40.65.254162.40.65.255126
133162.40.66.0/25162.40.66.1 to 162.40.66.126162.40.66.127126
134162.40.66.128/25162.40.66.129 to 162.40.66.254162.40.66.255126
135162.40.67.0/25162.40.67.1 to 162.40.67.126162.40.67.127126
136162.40.67.128/25162.40.67.129 to 162.40.67.254162.40.67.255126
137162.40.68.0/25162.40.68.1 to 162.40.68.126162.40.68.127126
138162.40.68.128/25162.40.68.129 to 162.40.68.254162.40.68.255126
139162.40.69.0/25162.40.69.1 to 162.40.69.126162.40.69.127126
140162.40.69.128/25162.40.69.129 to 162.40.69.254162.40.69.255126
141162.40.70.0/25162.40.70.1 to 162.40.70.126162.40.70.127126
142162.40.70.128/25162.40.70.129 to 162.40.70.254162.40.70.255126
143162.40.71.0/25162.40.71.1 to 162.40.71.126162.40.71.127126
144162.40.71.128/25162.40.71.129 to 162.40.71.254162.40.71.255126
145162.40.72.0/25162.40.72.1 to 162.40.72.126162.40.72.127126
146162.40.72.128/25162.40.72.129 to 162.40.72.254162.40.72.255126
147162.40.73.0/25162.40.73.1 to 162.40.73.126162.40.73.127126
148162.40.73.128/25162.40.73.129 to 162.40.73.254162.40.73.255126
149162.40.74.0/25162.40.74.1 to 162.40.74.126162.40.74.127126
150162.40.74.128/25162.40.74.129 to 162.40.74.254162.40.74.255126
151162.40.75.0/25162.40.75.1 to 162.40.75.126162.40.75.127126
152162.40.75.128/25162.40.75.129 to 162.40.75.254162.40.75.255126
153162.40.76.0/25162.40.76.1 to 162.40.76.126162.40.76.127126
154162.40.76.128/25162.40.76.129 to 162.40.76.254162.40.76.255126
155162.40.77.0/25162.40.77.1 to 162.40.77.126162.40.77.127126
156162.40.77.128/25162.40.77.129 to 162.40.77.254162.40.77.255126
157162.40.78.0/25162.40.78.1 to 162.40.78.126162.40.78.127126
158162.40.78.128/25162.40.78.129 to 162.40.78.254162.40.78.255126
159162.40.79.0/25162.40.79.1 to 162.40.79.126162.40.79.127126
160162.40.79.128/25162.40.79.129 to 162.40.79.254162.40.79.255126
161162.40.80.0/25162.40.80.1 to 162.40.80.126162.40.80.127126
162162.40.80.128/25162.40.80.129 to 162.40.80.254162.40.80.255126
163162.40.81.0/25162.40.81.1 to 162.40.81.126162.40.81.127126
164162.40.81.128/25162.40.81.129 to 162.40.81.254162.40.81.255126
165162.40.82.0/25162.40.82.1 to 162.40.82.126162.40.82.127126
166162.40.82.128/25162.40.82.129 to 162.40.82.254162.40.82.255126
167162.40.83.0/25162.40.83.1 to 162.40.83.126162.40.83.127126
168162.40.83.128/25162.40.83.129 to 162.40.83.254162.40.83.255126
169162.40.84.0/25162.40.84.1 to 162.40.84.126162.40.84.127126
170162.40.84.128/25162.40.84.129 to 162.40.84.254162.40.84.255126
171162.40.85.0/25162.40.85.1 to 162.40.85.126162.40.85.127126
172162.40.85.128/25162.40.85.129 to 162.40.85.254162.40.85.255126
173162.40.86.0/25162.40.86.1 to 162.40.86.126162.40.86.127126
174162.40.86.128/25162.40.86.129 to 162.40.86.254162.40.86.255126
175162.40.87.0/25162.40.87.1 to 162.40.87.126162.40.87.127126
176162.40.87.128/25162.40.87.129 to 162.40.87.254162.40.87.255126
177162.40.88.0/25162.40.88.1 to 162.40.88.126162.40.88.127126
178162.40.88.128/25162.40.88.129 to 162.40.88.254162.40.88.255126
179162.40.89.0/25162.40.89.1 to 162.40.89.126162.40.89.127126
180162.40.89.128/25162.40.89.129 to 162.40.89.254162.40.89.255126
181162.40.90.0/25162.40.90.1 to 162.40.90.126162.40.90.127126
182162.40.90.128/25162.40.90.129 to 162.40.90.254162.40.90.255126
183162.40.91.0/25162.40.91.1 to 162.40.91.126162.40.91.127126
184162.40.91.128/25162.40.91.129 to 162.40.91.254162.40.91.255126
185162.40.92.0/25162.40.92.1 to 162.40.92.126162.40.92.127126
186162.40.92.128/25162.40.92.129 to 162.40.92.254162.40.92.255126
187162.40.93.0/25162.40.93.1 to 162.40.93.126162.40.93.127126
188162.40.93.128/25162.40.93.129 to 162.40.93.254162.40.93.255126
189162.40.94.0/25162.40.94.1 to 162.40.94.126162.40.94.127126
190162.40.94.128/25162.40.94.129 to 162.40.94.254162.40.94.255126
191162.40.95.0/25162.40.95.1 to 162.40.95.126162.40.95.127126
192162.40.95.128/25162.40.95.129 to 162.40.95.254162.40.95.255126
193162.40.96.0/25162.40.96.1 to 162.40.96.126162.40.96.127126
194162.40.96.128/25162.40.96.129 to 162.40.96.254162.40.96.255126
195162.40.97.0/25162.40.97.1 to 162.40.97.126162.40.97.127126
196162.40.97.128/25162.40.97.129 to 162.40.97.254162.40.97.255126
197162.40.98.0/25162.40.98.1 to 162.40.98.126162.40.98.127126
198162.40.98.128/25162.40.98.129 to 162.40.98.254162.40.98.255126
199162.40.99.0/25162.40.99.1 to 162.40.99.126162.40.99.127126
200162.40.99.128/25162.40.99.129 to 162.40.99.254162.40.99.255126
201162.40.100.0/25162.40.100.1 to 162.40.100.126162.40.100.127126
202162.40.100.128/25162.40.100.129 to 162.40.100.254162.40.100.255126
203162.40.101.0/25162.40.101.1 to 162.40.101.126162.40.101.127126
204162.40.101.128/25162.40.101.129 to 162.40.101.254162.40.101.255126
205162.40.102.0/25162.40.102.1 to 162.40.102.126162.40.102.127126
206162.40.102.128/25162.40.102.129 to 162.40.102.254162.40.102.255126
207162.40.103.0/25162.40.103.1 to 162.40.103.126162.40.103.127126
208162.40.103.128/25162.40.103.129 to 162.40.103.254162.40.103.255126
209162.40.104.0/25162.40.104.1 to 162.40.104.126162.40.104.127126
210162.40.104.128/25162.40.104.129 to 162.40.104.254162.40.104.255126
211162.40.105.0/25162.40.105.1 to 162.40.105.126162.40.105.127126
212162.40.105.128/25162.40.105.129 to 162.40.105.254162.40.105.255126
213162.40.106.0/25162.40.106.1 to 162.40.106.126162.40.106.127126
214162.40.106.128/25162.40.106.129 to 162.40.106.254162.40.106.255126
215162.40.107.0/25162.40.107.1 to 162.40.107.126162.40.107.127126
216162.40.107.128/25162.40.107.129 to 162.40.107.254162.40.107.255126
217162.40.108.0/25162.40.108.1 to 162.40.108.126162.40.108.127126
218162.40.108.128/25162.40.108.129 to 162.40.108.254162.40.108.255126
219162.40.109.0/25162.40.109.1 to 162.40.109.126162.40.109.127126
220162.40.109.128/25162.40.109.129 to 162.40.109.254162.40.109.255126
221162.40.110.0/25162.40.110.1 to 162.40.110.126162.40.110.127126
222162.40.110.128/25162.40.110.129 to 162.40.110.254162.40.110.255126
223162.40.111.0/25162.40.111.1 to 162.40.111.126162.40.111.127126
224162.40.111.128/25162.40.111.129 to 162.40.111.254162.40.111.255126
225162.40.112.0/25162.40.112.1 to 162.40.112.126162.40.112.127126
226162.40.112.128/25162.40.112.129 to 162.40.112.254162.40.112.255126
227162.40.113.0/25162.40.113.1 to 162.40.113.126162.40.113.127126
228162.40.113.128/25162.40.113.129 to 162.40.113.254162.40.113.255126
229162.40.114.0/25162.40.114.1 to 162.40.114.126162.40.114.127126
230162.40.114.128/25162.40.114.129 to 162.40.114.254162.40.114.255126
231162.40.115.0/25162.40.115.1 to 162.40.115.126162.40.115.127126
232162.40.115.128/25162.40.115.129 to 162.40.115.254162.40.115.255126
233162.40.116.0/25162.40.116.1 to 162.40.116.126162.40.116.127126
234162.40.116.128/25162.40.116.129 to 162.40.116.254162.40.116.255126
235162.40.117.0/25162.40.117.1 to 162.40.117.126162.40.117.127126
236162.40.117.128/25162.40.117.129 to 162.40.117.254162.40.117.255126
237162.40.118.0/25162.40.118.1 to 162.40.118.126162.40.118.127126
238162.40.118.128/25162.40.118.129 to 162.40.118.254162.40.118.255126
239162.40.119.0/25162.40.119.1 to 162.40.119.126162.40.119.127126
240162.40.119.128/25162.40.119.129 to 162.40.119.254162.40.119.255126
241162.40.120.0/25162.40.120.1 to 162.40.120.126162.40.120.127126
242162.40.120.128/25162.40.120.129 to 162.40.120.254162.40.120.255126
243162.40.121.0/25162.40.121.1 to 162.40.121.126162.40.121.127126
244162.40.121.128/25162.40.121.129 to 162.40.121.254162.40.121.255126
245162.40.122.0/25162.40.122.1 to 162.40.122.126162.40.122.127126
246162.40.122.128/25162.40.122.129 to 162.40.122.254162.40.122.255126
247162.40.123.0/25162.40.123.1 to 162.40.123.126162.40.123.127126
248162.40.123.128/25162.40.123.129 to 162.40.123.254162.40.123.255126
249162.40.124.0/25162.40.124.1 to 162.40.124.126162.40.124.127126
250162.40.124.128/25162.40.124.129 to 162.40.124.254162.40.124.255126
251162.40.125.0/25162.40.125.1 to 162.40.125.126162.40.125.127126
252162.40.125.128/25162.40.125.129 to 162.40.125.254162.40.125.255126
253162.40.126.0/25162.40.126.1 to 162.40.126.126162.40.126.127126
254162.40.126.128/25162.40.126.129 to 162.40.126.254162.40.126.255126
255162.40.127.0/25162.40.127.1 to 162.40.127.126162.40.127.127126
256162.40.127.128/25162.40.127.129 to 162.40.127.254162.40.127.255126

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.