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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.

Network128.76.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
128.76.0.0
Broadcast address
128.77.255.255
First usable
128.76.0.1
Last usable
128.77.255.254
Usable hosts
131,070 (131,072 less the network and broadcast addresses)
Subnet mask
255.254.0.0
Wildcard mask
0.1.255.255 (Cisco ACLs, OSPF)
Prefix length
/15
Type
Public public
Old class
B (default /16)
As numbers
Hex 804C0000 · Integer 2152464384 to 2152595455
Reverse DNS zones
76.128.in-addr.arpa
77.128.in-addr.arpa
/15 is not on a 8-bit boundary, so it takes 2 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10000000.01001100.00000000.00000000128.76.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network10000000.01001100.00000000.00000000128.76.0.0
Broadcast10000000.01001101.11111111.11111111128.77.255.255
Split into smaller subnets/25

128.76.0.0/15 makes 1,024 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1128.76.0.0/25128.76.0.1 to 128.76.0.126128.76.0.127126
2128.76.0.128/25128.76.0.129 to 128.76.0.254128.76.0.255126
3128.76.1.0/25128.76.1.1 to 128.76.1.126128.76.1.127126
4128.76.1.128/25128.76.1.129 to 128.76.1.254128.76.1.255126
5128.76.2.0/25128.76.2.1 to 128.76.2.126128.76.2.127126
6128.76.2.128/25128.76.2.129 to 128.76.2.254128.76.2.255126
7128.76.3.0/25128.76.3.1 to 128.76.3.126128.76.3.127126
8128.76.3.128/25128.76.3.129 to 128.76.3.254128.76.3.255126
9128.76.4.0/25128.76.4.1 to 128.76.4.126128.76.4.127126
10128.76.4.128/25128.76.4.129 to 128.76.4.254128.76.4.255126
11128.76.5.0/25128.76.5.1 to 128.76.5.126128.76.5.127126
12128.76.5.128/25128.76.5.129 to 128.76.5.254128.76.5.255126
13128.76.6.0/25128.76.6.1 to 128.76.6.126128.76.6.127126
14128.76.6.128/25128.76.6.129 to 128.76.6.254128.76.6.255126
15128.76.7.0/25128.76.7.1 to 128.76.7.126128.76.7.127126
16128.76.7.128/25128.76.7.129 to 128.76.7.254128.76.7.255126
17128.76.8.0/25128.76.8.1 to 128.76.8.126128.76.8.127126
18128.76.8.128/25128.76.8.129 to 128.76.8.254128.76.8.255126
19128.76.9.0/25128.76.9.1 to 128.76.9.126128.76.9.127126
20128.76.9.128/25128.76.9.129 to 128.76.9.254128.76.9.255126
21128.76.10.0/25128.76.10.1 to 128.76.10.126128.76.10.127126
22128.76.10.128/25128.76.10.129 to 128.76.10.254128.76.10.255126
23128.76.11.0/25128.76.11.1 to 128.76.11.126128.76.11.127126
24128.76.11.128/25128.76.11.129 to 128.76.11.254128.76.11.255126
25128.76.12.0/25128.76.12.1 to 128.76.12.126128.76.12.127126
26128.76.12.128/25128.76.12.129 to 128.76.12.254128.76.12.255126
27128.76.13.0/25128.76.13.1 to 128.76.13.126128.76.13.127126
28128.76.13.128/25128.76.13.129 to 128.76.13.254128.76.13.255126
29128.76.14.0/25128.76.14.1 to 128.76.14.126128.76.14.127126
30128.76.14.128/25128.76.14.129 to 128.76.14.254128.76.14.255126
31128.76.15.0/25128.76.15.1 to 128.76.15.126128.76.15.127126
32128.76.15.128/25128.76.15.129 to 128.76.15.254128.76.15.255126
33128.76.16.0/25128.76.16.1 to 128.76.16.126128.76.16.127126
34128.76.16.128/25128.76.16.129 to 128.76.16.254128.76.16.255126
35128.76.17.0/25128.76.17.1 to 128.76.17.126128.76.17.127126
36128.76.17.128/25128.76.17.129 to 128.76.17.254128.76.17.255126
37128.76.18.0/25128.76.18.1 to 128.76.18.126128.76.18.127126
38128.76.18.128/25128.76.18.129 to 128.76.18.254128.76.18.255126
39128.76.19.0/25128.76.19.1 to 128.76.19.126128.76.19.127126
40128.76.19.128/25128.76.19.129 to 128.76.19.254128.76.19.255126
41128.76.20.0/25128.76.20.1 to 128.76.20.126128.76.20.127126
42128.76.20.128/25128.76.20.129 to 128.76.20.254128.76.20.255126
43128.76.21.0/25128.76.21.1 to 128.76.21.126128.76.21.127126
44128.76.21.128/25128.76.21.129 to 128.76.21.254128.76.21.255126
45128.76.22.0/25128.76.22.1 to 128.76.22.126128.76.22.127126
46128.76.22.128/25128.76.22.129 to 128.76.22.254128.76.22.255126
47128.76.23.0/25128.76.23.1 to 128.76.23.126128.76.23.127126
48128.76.23.128/25128.76.23.129 to 128.76.23.254128.76.23.255126
49128.76.24.0/25128.76.24.1 to 128.76.24.126128.76.24.127126
50128.76.24.128/25128.76.24.129 to 128.76.24.254128.76.24.255126
51128.76.25.0/25128.76.25.1 to 128.76.25.126128.76.25.127126
52128.76.25.128/25128.76.25.129 to 128.76.25.254128.76.25.255126
53128.76.26.0/25128.76.26.1 to 128.76.26.126128.76.26.127126
54128.76.26.128/25128.76.26.129 to 128.76.26.254128.76.26.255126
55128.76.27.0/25128.76.27.1 to 128.76.27.126128.76.27.127126
56128.76.27.128/25128.76.27.129 to 128.76.27.254128.76.27.255126
57128.76.28.0/25128.76.28.1 to 128.76.28.126128.76.28.127126
58128.76.28.128/25128.76.28.129 to 128.76.28.254128.76.28.255126
59128.76.29.0/25128.76.29.1 to 128.76.29.126128.76.29.127126
60128.76.29.128/25128.76.29.129 to 128.76.29.254128.76.29.255126
61128.76.30.0/25128.76.30.1 to 128.76.30.126128.76.30.127126
62128.76.30.128/25128.76.30.129 to 128.76.30.254128.76.30.255126
63128.76.31.0/25128.76.31.1 to 128.76.31.126128.76.31.127126
64128.76.31.128/25128.76.31.129 to 128.76.31.254128.76.31.255126
65128.76.32.0/25128.76.32.1 to 128.76.32.126128.76.32.127126
66128.76.32.128/25128.76.32.129 to 128.76.32.254128.76.32.255126
67128.76.33.0/25128.76.33.1 to 128.76.33.126128.76.33.127126
68128.76.33.128/25128.76.33.129 to 128.76.33.254128.76.33.255126
69128.76.34.0/25128.76.34.1 to 128.76.34.126128.76.34.127126
70128.76.34.128/25128.76.34.129 to 128.76.34.254128.76.34.255126
71128.76.35.0/25128.76.35.1 to 128.76.35.126128.76.35.127126
72128.76.35.128/25128.76.35.129 to 128.76.35.254128.76.35.255126
73128.76.36.0/25128.76.36.1 to 128.76.36.126128.76.36.127126
74128.76.36.128/25128.76.36.129 to 128.76.36.254128.76.36.255126
75128.76.37.0/25128.76.37.1 to 128.76.37.126128.76.37.127126
76128.76.37.128/25128.76.37.129 to 128.76.37.254128.76.37.255126
77128.76.38.0/25128.76.38.1 to 128.76.38.126128.76.38.127126
78128.76.38.128/25128.76.38.129 to 128.76.38.254128.76.38.255126
79128.76.39.0/25128.76.39.1 to 128.76.39.126128.76.39.127126
80128.76.39.128/25128.76.39.129 to 128.76.39.254128.76.39.255126
81128.76.40.0/25128.76.40.1 to 128.76.40.126128.76.40.127126
82128.76.40.128/25128.76.40.129 to 128.76.40.254128.76.40.255126
83128.76.41.0/25128.76.41.1 to 128.76.41.126128.76.41.127126
84128.76.41.128/25128.76.41.129 to 128.76.41.254128.76.41.255126
85128.76.42.0/25128.76.42.1 to 128.76.42.126128.76.42.127126
86128.76.42.128/25128.76.42.129 to 128.76.42.254128.76.42.255126
87128.76.43.0/25128.76.43.1 to 128.76.43.126128.76.43.127126
88128.76.43.128/25128.76.43.129 to 128.76.43.254128.76.43.255126
89128.76.44.0/25128.76.44.1 to 128.76.44.126128.76.44.127126
90128.76.44.128/25128.76.44.129 to 128.76.44.254128.76.44.255126
91128.76.45.0/25128.76.45.1 to 128.76.45.126128.76.45.127126
92128.76.45.128/25128.76.45.129 to 128.76.45.254128.76.45.255126
93128.76.46.0/25128.76.46.1 to 128.76.46.126128.76.46.127126
94128.76.46.128/25128.76.46.129 to 128.76.46.254128.76.46.255126
95128.76.47.0/25128.76.47.1 to 128.76.47.126128.76.47.127126
96128.76.47.128/25128.76.47.129 to 128.76.47.254128.76.47.255126
97128.76.48.0/25128.76.48.1 to 128.76.48.126128.76.48.127126
98128.76.48.128/25128.76.48.129 to 128.76.48.254128.76.48.255126
99128.76.49.0/25128.76.49.1 to 128.76.49.126128.76.49.127126
100128.76.49.128/25128.76.49.129 to 128.76.49.254128.76.49.255126
101128.76.50.0/25128.76.50.1 to 128.76.50.126128.76.50.127126
102128.76.50.128/25128.76.50.129 to 128.76.50.254128.76.50.255126
103128.76.51.0/25128.76.51.1 to 128.76.51.126128.76.51.127126
104128.76.51.128/25128.76.51.129 to 128.76.51.254128.76.51.255126
105128.76.52.0/25128.76.52.1 to 128.76.52.126128.76.52.127126
106128.76.52.128/25128.76.52.129 to 128.76.52.254128.76.52.255126
107128.76.53.0/25128.76.53.1 to 128.76.53.126128.76.53.127126
108128.76.53.128/25128.76.53.129 to 128.76.53.254128.76.53.255126
109128.76.54.0/25128.76.54.1 to 128.76.54.126128.76.54.127126
110128.76.54.128/25128.76.54.129 to 128.76.54.254128.76.54.255126
111128.76.55.0/25128.76.55.1 to 128.76.55.126128.76.55.127126
112128.76.55.128/25128.76.55.129 to 128.76.55.254128.76.55.255126
113128.76.56.0/25128.76.56.1 to 128.76.56.126128.76.56.127126
114128.76.56.128/25128.76.56.129 to 128.76.56.254128.76.56.255126
115128.76.57.0/25128.76.57.1 to 128.76.57.126128.76.57.127126
116128.76.57.128/25128.76.57.129 to 128.76.57.254128.76.57.255126
117128.76.58.0/25128.76.58.1 to 128.76.58.126128.76.58.127126
118128.76.58.128/25128.76.58.129 to 128.76.58.254128.76.58.255126
119128.76.59.0/25128.76.59.1 to 128.76.59.126128.76.59.127126
120128.76.59.128/25128.76.59.129 to 128.76.59.254128.76.59.255126
121128.76.60.0/25128.76.60.1 to 128.76.60.126128.76.60.127126
122128.76.60.128/25128.76.60.129 to 128.76.60.254128.76.60.255126
123128.76.61.0/25128.76.61.1 to 128.76.61.126128.76.61.127126
124128.76.61.128/25128.76.61.129 to 128.76.61.254128.76.61.255126
125128.76.62.0/25128.76.62.1 to 128.76.62.126128.76.62.127126
126128.76.62.128/25128.76.62.129 to 128.76.62.254128.76.62.255126
127128.76.63.0/25128.76.63.1 to 128.76.63.126128.76.63.127126
128128.76.63.128/25128.76.63.129 to 128.76.63.254128.76.63.255126
129128.76.64.0/25128.76.64.1 to 128.76.64.126128.76.64.127126
130128.76.64.128/25128.76.64.129 to 128.76.64.254128.76.64.255126
131128.76.65.0/25128.76.65.1 to 128.76.65.126128.76.65.127126
132128.76.65.128/25128.76.65.129 to 128.76.65.254128.76.65.255126
133128.76.66.0/25128.76.66.1 to 128.76.66.126128.76.66.127126
134128.76.66.128/25128.76.66.129 to 128.76.66.254128.76.66.255126
135128.76.67.0/25128.76.67.1 to 128.76.67.126128.76.67.127126
136128.76.67.128/25128.76.67.129 to 128.76.67.254128.76.67.255126
137128.76.68.0/25128.76.68.1 to 128.76.68.126128.76.68.127126
138128.76.68.128/25128.76.68.129 to 128.76.68.254128.76.68.255126
139128.76.69.0/25128.76.69.1 to 128.76.69.126128.76.69.127126
140128.76.69.128/25128.76.69.129 to 128.76.69.254128.76.69.255126
141128.76.70.0/25128.76.70.1 to 128.76.70.126128.76.70.127126
142128.76.70.128/25128.76.70.129 to 128.76.70.254128.76.70.255126
143128.76.71.0/25128.76.71.1 to 128.76.71.126128.76.71.127126
144128.76.71.128/25128.76.71.129 to 128.76.71.254128.76.71.255126
145128.76.72.0/25128.76.72.1 to 128.76.72.126128.76.72.127126
146128.76.72.128/25128.76.72.129 to 128.76.72.254128.76.72.255126
147128.76.73.0/25128.76.73.1 to 128.76.73.126128.76.73.127126
148128.76.73.128/25128.76.73.129 to 128.76.73.254128.76.73.255126
149128.76.74.0/25128.76.74.1 to 128.76.74.126128.76.74.127126
150128.76.74.128/25128.76.74.129 to 128.76.74.254128.76.74.255126
151128.76.75.0/25128.76.75.1 to 128.76.75.126128.76.75.127126
152128.76.75.128/25128.76.75.129 to 128.76.75.254128.76.75.255126
153128.76.76.0/25128.76.76.1 to 128.76.76.126128.76.76.127126
154128.76.76.128/25128.76.76.129 to 128.76.76.254128.76.76.255126
155128.76.77.0/25128.76.77.1 to 128.76.77.126128.76.77.127126
156128.76.77.128/25128.76.77.129 to 128.76.77.254128.76.77.255126
157128.76.78.0/25128.76.78.1 to 128.76.78.126128.76.78.127126
158128.76.78.128/25128.76.78.129 to 128.76.78.254128.76.78.255126
159128.76.79.0/25128.76.79.1 to 128.76.79.126128.76.79.127126
160128.76.79.128/25128.76.79.129 to 128.76.79.254128.76.79.255126
161128.76.80.0/25128.76.80.1 to 128.76.80.126128.76.80.127126
162128.76.80.128/25128.76.80.129 to 128.76.80.254128.76.80.255126
163128.76.81.0/25128.76.81.1 to 128.76.81.126128.76.81.127126
164128.76.81.128/25128.76.81.129 to 128.76.81.254128.76.81.255126
165128.76.82.0/25128.76.82.1 to 128.76.82.126128.76.82.127126
166128.76.82.128/25128.76.82.129 to 128.76.82.254128.76.82.255126
167128.76.83.0/25128.76.83.1 to 128.76.83.126128.76.83.127126
168128.76.83.128/25128.76.83.129 to 128.76.83.254128.76.83.255126
169128.76.84.0/25128.76.84.1 to 128.76.84.126128.76.84.127126
170128.76.84.128/25128.76.84.129 to 128.76.84.254128.76.84.255126
171128.76.85.0/25128.76.85.1 to 128.76.85.126128.76.85.127126
172128.76.85.128/25128.76.85.129 to 128.76.85.254128.76.85.255126
173128.76.86.0/25128.76.86.1 to 128.76.86.126128.76.86.127126
174128.76.86.128/25128.76.86.129 to 128.76.86.254128.76.86.255126
175128.76.87.0/25128.76.87.1 to 128.76.87.126128.76.87.127126
176128.76.87.128/25128.76.87.129 to 128.76.87.254128.76.87.255126
177128.76.88.0/25128.76.88.1 to 128.76.88.126128.76.88.127126
178128.76.88.128/25128.76.88.129 to 128.76.88.254128.76.88.255126
179128.76.89.0/25128.76.89.1 to 128.76.89.126128.76.89.127126
180128.76.89.128/25128.76.89.129 to 128.76.89.254128.76.89.255126
181128.76.90.0/25128.76.90.1 to 128.76.90.126128.76.90.127126
182128.76.90.128/25128.76.90.129 to 128.76.90.254128.76.90.255126
183128.76.91.0/25128.76.91.1 to 128.76.91.126128.76.91.127126
184128.76.91.128/25128.76.91.129 to 128.76.91.254128.76.91.255126
185128.76.92.0/25128.76.92.1 to 128.76.92.126128.76.92.127126
186128.76.92.128/25128.76.92.129 to 128.76.92.254128.76.92.255126
187128.76.93.0/25128.76.93.1 to 128.76.93.126128.76.93.127126
188128.76.93.128/25128.76.93.129 to 128.76.93.254128.76.93.255126
189128.76.94.0/25128.76.94.1 to 128.76.94.126128.76.94.127126
190128.76.94.128/25128.76.94.129 to 128.76.94.254128.76.94.255126
191128.76.95.0/25128.76.95.1 to 128.76.95.126128.76.95.127126
192128.76.95.128/25128.76.95.129 to 128.76.95.254128.76.95.255126
193128.76.96.0/25128.76.96.1 to 128.76.96.126128.76.96.127126
194128.76.96.128/25128.76.96.129 to 128.76.96.254128.76.96.255126
195128.76.97.0/25128.76.97.1 to 128.76.97.126128.76.97.127126
196128.76.97.128/25128.76.97.129 to 128.76.97.254128.76.97.255126
197128.76.98.0/25128.76.98.1 to 128.76.98.126128.76.98.127126
198128.76.98.128/25128.76.98.129 to 128.76.98.254128.76.98.255126
199128.76.99.0/25128.76.99.1 to 128.76.99.126128.76.99.127126
200128.76.99.128/25128.76.99.129 to 128.76.99.254128.76.99.255126
201128.76.100.0/25128.76.100.1 to 128.76.100.126128.76.100.127126
202128.76.100.128/25128.76.100.129 to 128.76.100.254128.76.100.255126
203128.76.101.0/25128.76.101.1 to 128.76.101.126128.76.101.127126
204128.76.101.128/25128.76.101.129 to 128.76.101.254128.76.101.255126
205128.76.102.0/25128.76.102.1 to 128.76.102.126128.76.102.127126
206128.76.102.128/25128.76.102.129 to 128.76.102.254128.76.102.255126
207128.76.103.0/25128.76.103.1 to 128.76.103.126128.76.103.127126
208128.76.103.128/25128.76.103.129 to 128.76.103.254128.76.103.255126
209128.76.104.0/25128.76.104.1 to 128.76.104.126128.76.104.127126
210128.76.104.128/25128.76.104.129 to 128.76.104.254128.76.104.255126
211128.76.105.0/25128.76.105.1 to 128.76.105.126128.76.105.127126
212128.76.105.128/25128.76.105.129 to 128.76.105.254128.76.105.255126
213128.76.106.0/25128.76.106.1 to 128.76.106.126128.76.106.127126
214128.76.106.128/25128.76.106.129 to 128.76.106.254128.76.106.255126
215128.76.107.0/25128.76.107.1 to 128.76.107.126128.76.107.127126
216128.76.107.128/25128.76.107.129 to 128.76.107.254128.76.107.255126
217128.76.108.0/25128.76.108.1 to 128.76.108.126128.76.108.127126
218128.76.108.128/25128.76.108.129 to 128.76.108.254128.76.108.255126
219128.76.109.0/25128.76.109.1 to 128.76.109.126128.76.109.127126
220128.76.109.128/25128.76.109.129 to 128.76.109.254128.76.109.255126
221128.76.110.0/25128.76.110.1 to 128.76.110.126128.76.110.127126
222128.76.110.128/25128.76.110.129 to 128.76.110.254128.76.110.255126
223128.76.111.0/25128.76.111.1 to 128.76.111.126128.76.111.127126
224128.76.111.128/25128.76.111.129 to 128.76.111.254128.76.111.255126
225128.76.112.0/25128.76.112.1 to 128.76.112.126128.76.112.127126
226128.76.112.128/25128.76.112.129 to 128.76.112.254128.76.112.255126
227128.76.113.0/25128.76.113.1 to 128.76.113.126128.76.113.127126
228128.76.113.128/25128.76.113.129 to 128.76.113.254128.76.113.255126
229128.76.114.0/25128.76.114.1 to 128.76.114.126128.76.114.127126
230128.76.114.128/25128.76.114.129 to 128.76.114.254128.76.114.255126
231128.76.115.0/25128.76.115.1 to 128.76.115.126128.76.115.127126
232128.76.115.128/25128.76.115.129 to 128.76.115.254128.76.115.255126
233128.76.116.0/25128.76.116.1 to 128.76.116.126128.76.116.127126
234128.76.116.128/25128.76.116.129 to 128.76.116.254128.76.116.255126
235128.76.117.0/25128.76.117.1 to 128.76.117.126128.76.117.127126
236128.76.117.128/25128.76.117.129 to 128.76.117.254128.76.117.255126
237128.76.118.0/25128.76.118.1 to 128.76.118.126128.76.118.127126
238128.76.118.128/25128.76.118.129 to 128.76.118.254128.76.118.255126
239128.76.119.0/25128.76.119.1 to 128.76.119.126128.76.119.127126
240128.76.119.128/25128.76.119.129 to 128.76.119.254128.76.119.255126
241128.76.120.0/25128.76.120.1 to 128.76.120.126128.76.120.127126
242128.76.120.128/25128.76.120.129 to 128.76.120.254128.76.120.255126
243128.76.121.0/25128.76.121.1 to 128.76.121.126128.76.121.127126
244128.76.121.128/25128.76.121.129 to 128.76.121.254128.76.121.255126
245128.76.122.0/25128.76.122.1 to 128.76.122.126128.76.122.127126
246128.76.122.128/25128.76.122.129 to 128.76.122.254128.76.122.255126
247128.76.123.0/25128.76.123.1 to 128.76.123.126128.76.123.127126
248128.76.123.128/25128.76.123.129 to 128.76.123.254128.76.123.255126
249128.76.124.0/25128.76.124.1 to 128.76.124.126128.76.124.127126
250128.76.124.128/25128.76.124.129 to 128.76.124.254128.76.124.255126
251128.76.125.0/25128.76.125.1 to 128.76.125.126128.76.125.127126
252128.76.125.128/25128.76.125.129 to 128.76.125.254128.76.125.255126
253128.76.126.0/25128.76.126.1 to 128.76.126.126128.76.126.127126
254128.76.126.128/25128.76.126.129 to 128.76.126.254128.76.126.255126
255128.76.127.0/25128.76.127.1 to 128.76.127.126128.76.127.127126
256128.76.127.128/25128.76.127.129 to 128.76.127.254128.76.127.255126

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