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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.

Network174.26.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
174.26.0.0
Broadcast address
174.27.255.255
First usable
174.26.0.1
Last usable
174.27.255.254
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 AE1A0000 · Integer 2920939520 to 2921070591
Reverse DNS zones
26.174.in-addr.arpa
27.174.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
Address10101110.00011010.00000000.00000000174.26.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network10101110.00011010.00000000.00000000174.26.0.0
Broadcast10101110.00011011.11111111.11111111174.27.255.255
Split into smaller subnets/25
/16 (2)/17 (4)/18 (8)/19 (16)/20 (32)/21 (64)/22 (128)/23 (256)/24 (512)/25 (1,024)/26 (2,048)/27 (4,096)

174.26.0.0/15 makes 1,024 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1174.26.0.0/25174.26.0.1 to 174.26.0.126174.26.0.127126
2174.26.0.128/25174.26.0.129 to 174.26.0.254174.26.0.255126
3174.26.1.0/25174.26.1.1 to 174.26.1.126174.26.1.127126
4174.26.1.128/25174.26.1.129 to 174.26.1.254174.26.1.255126
5174.26.2.0/25174.26.2.1 to 174.26.2.126174.26.2.127126
6174.26.2.128/25174.26.2.129 to 174.26.2.254174.26.2.255126
7174.26.3.0/25174.26.3.1 to 174.26.3.126174.26.3.127126
8174.26.3.128/25174.26.3.129 to 174.26.3.254174.26.3.255126
9174.26.4.0/25174.26.4.1 to 174.26.4.126174.26.4.127126
10174.26.4.128/25174.26.4.129 to 174.26.4.254174.26.4.255126
11174.26.5.0/25174.26.5.1 to 174.26.5.126174.26.5.127126
12174.26.5.128/25174.26.5.129 to 174.26.5.254174.26.5.255126
13174.26.6.0/25174.26.6.1 to 174.26.6.126174.26.6.127126
14174.26.6.128/25174.26.6.129 to 174.26.6.254174.26.6.255126
15174.26.7.0/25174.26.7.1 to 174.26.7.126174.26.7.127126
16174.26.7.128/25174.26.7.129 to 174.26.7.254174.26.7.255126
17174.26.8.0/25174.26.8.1 to 174.26.8.126174.26.8.127126
18174.26.8.128/25174.26.8.129 to 174.26.8.254174.26.8.255126
19174.26.9.0/25174.26.9.1 to 174.26.9.126174.26.9.127126
20174.26.9.128/25174.26.9.129 to 174.26.9.254174.26.9.255126
21174.26.10.0/25174.26.10.1 to 174.26.10.126174.26.10.127126
22174.26.10.128/25174.26.10.129 to 174.26.10.254174.26.10.255126
23174.26.11.0/25174.26.11.1 to 174.26.11.126174.26.11.127126
24174.26.11.128/25174.26.11.129 to 174.26.11.254174.26.11.255126
25174.26.12.0/25174.26.12.1 to 174.26.12.126174.26.12.127126
26174.26.12.128/25174.26.12.129 to 174.26.12.254174.26.12.255126
27174.26.13.0/25174.26.13.1 to 174.26.13.126174.26.13.127126
28174.26.13.128/25174.26.13.129 to 174.26.13.254174.26.13.255126
29174.26.14.0/25174.26.14.1 to 174.26.14.126174.26.14.127126
30174.26.14.128/25174.26.14.129 to 174.26.14.254174.26.14.255126
31174.26.15.0/25174.26.15.1 to 174.26.15.126174.26.15.127126
32174.26.15.128/25174.26.15.129 to 174.26.15.254174.26.15.255126
33174.26.16.0/25174.26.16.1 to 174.26.16.126174.26.16.127126
34174.26.16.128/25174.26.16.129 to 174.26.16.254174.26.16.255126
35174.26.17.0/25174.26.17.1 to 174.26.17.126174.26.17.127126
36174.26.17.128/25174.26.17.129 to 174.26.17.254174.26.17.255126
37174.26.18.0/25174.26.18.1 to 174.26.18.126174.26.18.127126
38174.26.18.128/25174.26.18.129 to 174.26.18.254174.26.18.255126
39174.26.19.0/25174.26.19.1 to 174.26.19.126174.26.19.127126
40174.26.19.128/25174.26.19.129 to 174.26.19.254174.26.19.255126
41174.26.20.0/25174.26.20.1 to 174.26.20.126174.26.20.127126
42174.26.20.128/25174.26.20.129 to 174.26.20.254174.26.20.255126
43174.26.21.0/25174.26.21.1 to 174.26.21.126174.26.21.127126
44174.26.21.128/25174.26.21.129 to 174.26.21.254174.26.21.255126
45174.26.22.0/25174.26.22.1 to 174.26.22.126174.26.22.127126
46174.26.22.128/25174.26.22.129 to 174.26.22.254174.26.22.255126
47174.26.23.0/25174.26.23.1 to 174.26.23.126174.26.23.127126
48174.26.23.128/25174.26.23.129 to 174.26.23.254174.26.23.255126
49174.26.24.0/25174.26.24.1 to 174.26.24.126174.26.24.127126
50174.26.24.128/25174.26.24.129 to 174.26.24.254174.26.24.255126
51174.26.25.0/25174.26.25.1 to 174.26.25.126174.26.25.127126
52174.26.25.128/25174.26.25.129 to 174.26.25.254174.26.25.255126
53174.26.26.0/25174.26.26.1 to 174.26.26.126174.26.26.127126
54174.26.26.128/25174.26.26.129 to 174.26.26.254174.26.26.255126
55174.26.27.0/25174.26.27.1 to 174.26.27.126174.26.27.127126
56174.26.27.128/25174.26.27.129 to 174.26.27.254174.26.27.255126
57174.26.28.0/25174.26.28.1 to 174.26.28.126174.26.28.127126
58174.26.28.128/25174.26.28.129 to 174.26.28.254174.26.28.255126
59174.26.29.0/25174.26.29.1 to 174.26.29.126174.26.29.127126
60174.26.29.128/25174.26.29.129 to 174.26.29.254174.26.29.255126
61174.26.30.0/25174.26.30.1 to 174.26.30.126174.26.30.127126
62174.26.30.128/25174.26.30.129 to 174.26.30.254174.26.30.255126
63174.26.31.0/25174.26.31.1 to 174.26.31.126174.26.31.127126
64174.26.31.128/25174.26.31.129 to 174.26.31.254174.26.31.255126
65174.26.32.0/25174.26.32.1 to 174.26.32.126174.26.32.127126
66174.26.32.128/25174.26.32.129 to 174.26.32.254174.26.32.255126
67174.26.33.0/25174.26.33.1 to 174.26.33.126174.26.33.127126
68174.26.33.128/25174.26.33.129 to 174.26.33.254174.26.33.255126
69174.26.34.0/25174.26.34.1 to 174.26.34.126174.26.34.127126
70174.26.34.128/25174.26.34.129 to 174.26.34.254174.26.34.255126
71174.26.35.0/25174.26.35.1 to 174.26.35.126174.26.35.127126
72174.26.35.128/25174.26.35.129 to 174.26.35.254174.26.35.255126
73174.26.36.0/25174.26.36.1 to 174.26.36.126174.26.36.127126
74174.26.36.128/25174.26.36.129 to 174.26.36.254174.26.36.255126
75174.26.37.0/25174.26.37.1 to 174.26.37.126174.26.37.127126
76174.26.37.128/25174.26.37.129 to 174.26.37.254174.26.37.255126
77174.26.38.0/25174.26.38.1 to 174.26.38.126174.26.38.127126
78174.26.38.128/25174.26.38.129 to 174.26.38.254174.26.38.255126
79174.26.39.0/25174.26.39.1 to 174.26.39.126174.26.39.127126
80174.26.39.128/25174.26.39.129 to 174.26.39.254174.26.39.255126
81174.26.40.0/25174.26.40.1 to 174.26.40.126174.26.40.127126
82174.26.40.128/25174.26.40.129 to 174.26.40.254174.26.40.255126
83174.26.41.0/25174.26.41.1 to 174.26.41.126174.26.41.127126
84174.26.41.128/25174.26.41.129 to 174.26.41.254174.26.41.255126
85174.26.42.0/25174.26.42.1 to 174.26.42.126174.26.42.127126
86174.26.42.128/25174.26.42.129 to 174.26.42.254174.26.42.255126
87174.26.43.0/25174.26.43.1 to 174.26.43.126174.26.43.127126
88174.26.43.128/25174.26.43.129 to 174.26.43.254174.26.43.255126
89174.26.44.0/25174.26.44.1 to 174.26.44.126174.26.44.127126
90174.26.44.128/25174.26.44.129 to 174.26.44.254174.26.44.255126
91174.26.45.0/25174.26.45.1 to 174.26.45.126174.26.45.127126
92174.26.45.128/25174.26.45.129 to 174.26.45.254174.26.45.255126
93174.26.46.0/25174.26.46.1 to 174.26.46.126174.26.46.127126
94174.26.46.128/25174.26.46.129 to 174.26.46.254174.26.46.255126
95174.26.47.0/25174.26.47.1 to 174.26.47.126174.26.47.127126
96174.26.47.128/25174.26.47.129 to 174.26.47.254174.26.47.255126
97174.26.48.0/25174.26.48.1 to 174.26.48.126174.26.48.127126
98174.26.48.128/25174.26.48.129 to 174.26.48.254174.26.48.255126
99174.26.49.0/25174.26.49.1 to 174.26.49.126174.26.49.127126
100174.26.49.128/25174.26.49.129 to 174.26.49.254174.26.49.255126
101174.26.50.0/25174.26.50.1 to 174.26.50.126174.26.50.127126
102174.26.50.128/25174.26.50.129 to 174.26.50.254174.26.50.255126
103174.26.51.0/25174.26.51.1 to 174.26.51.126174.26.51.127126
104174.26.51.128/25174.26.51.129 to 174.26.51.254174.26.51.255126
105174.26.52.0/25174.26.52.1 to 174.26.52.126174.26.52.127126
106174.26.52.128/25174.26.52.129 to 174.26.52.254174.26.52.255126
107174.26.53.0/25174.26.53.1 to 174.26.53.126174.26.53.127126
108174.26.53.128/25174.26.53.129 to 174.26.53.254174.26.53.255126
109174.26.54.0/25174.26.54.1 to 174.26.54.126174.26.54.127126
110174.26.54.128/25174.26.54.129 to 174.26.54.254174.26.54.255126
111174.26.55.0/25174.26.55.1 to 174.26.55.126174.26.55.127126
112174.26.55.128/25174.26.55.129 to 174.26.55.254174.26.55.255126
113174.26.56.0/25174.26.56.1 to 174.26.56.126174.26.56.127126
114174.26.56.128/25174.26.56.129 to 174.26.56.254174.26.56.255126
115174.26.57.0/25174.26.57.1 to 174.26.57.126174.26.57.127126
116174.26.57.128/25174.26.57.129 to 174.26.57.254174.26.57.255126
117174.26.58.0/25174.26.58.1 to 174.26.58.126174.26.58.127126
118174.26.58.128/25174.26.58.129 to 174.26.58.254174.26.58.255126
119174.26.59.0/25174.26.59.1 to 174.26.59.126174.26.59.127126
120174.26.59.128/25174.26.59.129 to 174.26.59.254174.26.59.255126
121174.26.60.0/25174.26.60.1 to 174.26.60.126174.26.60.127126
122174.26.60.128/25174.26.60.129 to 174.26.60.254174.26.60.255126
123174.26.61.0/25174.26.61.1 to 174.26.61.126174.26.61.127126
124174.26.61.128/25174.26.61.129 to 174.26.61.254174.26.61.255126
125174.26.62.0/25174.26.62.1 to 174.26.62.126174.26.62.127126
126174.26.62.128/25174.26.62.129 to 174.26.62.254174.26.62.255126
127174.26.63.0/25174.26.63.1 to 174.26.63.126174.26.63.127126
128174.26.63.128/25174.26.63.129 to 174.26.63.254174.26.63.255126
129174.26.64.0/25174.26.64.1 to 174.26.64.126174.26.64.127126
130174.26.64.128/25174.26.64.129 to 174.26.64.254174.26.64.255126
131174.26.65.0/25174.26.65.1 to 174.26.65.126174.26.65.127126
132174.26.65.128/25174.26.65.129 to 174.26.65.254174.26.65.255126
133174.26.66.0/25174.26.66.1 to 174.26.66.126174.26.66.127126
134174.26.66.128/25174.26.66.129 to 174.26.66.254174.26.66.255126
135174.26.67.0/25174.26.67.1 to 174.26.67.126174.26.67.127126
136174.26.67.128/25174.26.67.129 to 174.26.67.254174.26.67.255126
137174.26.68.0/25174.26.68.1 to 174.26.68.126174.26.68.127126
138174.26.68.128/25174.26.68.129 to 174.26.68.254174.26.68.255126
139174.26.69.0/25174.26.69.1 to 174.26.69.126174.26.69.127126
140174.26.69.128/25174.26.69.129 to 174.26.69.254174.26.69.255126
141174.26.70.0/25174.26.70.1 to 174.26.70.126174.26.70.127126
142174.26.70.128/25174.26.70.129 to 174.26.70.254174.26.70.255126
143174.26.71.0/25174.26.71.1 to 174.26.71.126174.26.71.127126
144174.26.71.128/25174.26.71.129 to 174.26.71.254174.26.71.255126
145174.26.72.0/25174.26.72.1 to 174.26.72.126174.26.72.127126
146174.26.72.128/25174.26.72.129 to 174.26.72.254174.26.72.255126
147174.26.73.0/25174.26.73.1 to 174.26.73.126174.26.73.127126
148174.26.73.128/25174.26.73.129 to 174.26.73.254174.26.73.255126
149174.26.74.0/25174.26.74.1 to 174.26.74.126174.26.74.127126
150174.26.74.128/25174.26.74.129 to 174.26.74.254174.26.74.255126
151174.26.75.0/25174.26.75.1 to 174.26.75.126174.26.75.127126
152174.26.75.128/25174.26.75.129 to 174.26.75.254174.26.75.255126
153174.26.76.0/25174.26.76.1 to 174.26.76.126174.26.76.127126
154174.26.76.128/25174.26.76.129 to 174.26.76.254174.26.76.255126
155174.26.77.0/25174.26.77.1 to 174.26.77.126174.26.77.127126
156174.26.77.128/25174.26.77.129 to 174.26.77.254174.26.77.255126
157174.26.78.0/25174.26.78.1 to 174.26.78.126174.26.78.127126
158174.26.78.128/25174.26.78.129 to 174.26.78.254174.26.78.255126
159174.26.79.0/25174.26.79.1 to 174.26.79.126174.26.79.127126
160174.26.79.128/25174.26.79.129 to 174.26.79.254174.26.79.255126
161174.26.80.0/25174.26.80.1 to 174.26.80.126174.26.80.127126
162174.26.80.128/25174.26.80.129 to 174.26.80.254174.26.80.255126
163174.26.81.0/25174.26.81.1 to 174.26.81.126174.26.81.127126
164174.26.81.128/25174.26.81.129 to 174.26.81.254174.26.81.255126
165174.26.82.0/25174.26.82.1 to 174.26.82.126174.26.82.127126
166174.26.82.128/25174.26.82.129 to 174.26.82.254174.26.82.255126
167174.26.83.0/25174.26.83.1 to 174.26.83.126174.26.83.127126
168174.26.83.128/25174.26.83.129 to 174.26.83.254174.26.83.255126
169174.26.84.0/25174.26.84.1 to 174.26.84.126174.26.84.127126
170174.26.84.128/25174.26.84.129 to 174.26.84.254174.26.84.255126
171174.26.85.0/25174.26.85.1 to 174.26.85.126174.26.85.127126
172174.26.85.128/25174.26.85.129 to 174.26.85.254174.26.85.255126
173174.26.86.0/25174.26.86.1 to 174.26.86.126174.26.86.127126
174174.26.86.128/25174.26.86.129 to 174.26.86.254174.26.86.255126
175174.26.87.0/25174.26.87.1 to 174.26.87.126174.26.87.127126
176174.26.87.128/25174.26.87.129 to 174.26.87.254174.26.87.255126
177174.26.88.0/25174.26.88.1 to 174.26.88.126174.26.88.127126
178174.26.88.128/25174.26.88.129 to 174.26.88.254174.26.88.255126
179174.26.89.0/25174.26.89.1 to 174.26.89.126174.26.89.127126
180174.26.89.128/25174.26.89.129 to 174.26.89.254174.26.89.255126
181174.26.90.0/25174.26.90.1 to 174.26.90.126174.26.90.127126
182174.26.90.128/25174.26.90.129 to 174.26.90.254174.26.90.255126
183174.26.91.0/25174.26.91.1 to 174.26.91.126174.26.91.127126
184174.26.91.128/25174.26.91.129 to 174.26.91.254174.26.91.255126
185174.26.92.0/25174.26.92.1 to 174.26.92.126174.26.92.127126
186174.26.92.128/25174.26.92.129 to 174.26.92.254174.26.92.255126
187174.26.93.0/25174.26.93.1 to 174.26.93.126174.26.93.127126
188174.26.93.128/25174.26.93.129 to 174.26.93.254174.26.93.255126
189174.26.94.0/25174.26.94.1 to 174.26.94.126174.26.94.127126
190174.26.94.128/25174.26.94.129 to 174.26.94.254174.26.94.255126
191174.26.95.0/25174.26.95.1 to 174.26.95.126174.26.95.127126
192174.26.95.128/25174.26.95.129 to 174.26.95.254174.26.95.255126
193174.26.96.0/25174.26.96.1 to 174.26.96.126174.26.96.127126
194174.26.96.128/25174.26.96.129 to 174.26.96.254174.26.96.255126
195174.26.97.0/25174.26.97.1 to 174.26.97.126174.26.97.127126
196174.26.97.128/25174.26.97.129 to 174.26.97.254174.26.97.255126
197174.26.98.0/25174.26.98.1 to 174.26.98.126174.26.98.127126
198174.26.98.128/25174.26.98.129 to 174.26.98.254174.26.98.255126
199174.26.99.0/25174.26.99.1 to 174.26.99.126174.26.99.127126
200174.26.99.128/25174.26.99.129 to 174.26.99.254174.26.99.255126
201174.26.100.0/25174.26.100.1 to 174.26.100.126174.26.100.127126
202174.26.100.128/25174.26.100.129 to 174.26.100.254174.26.100.255126
203174.26.101.0/25174.26.101.1 to 174.26.101.126174.26.101.127126
204174.26.101.128/25174.26.101.129 to 174.26.101.254174.26.101.255126
205174.26.102.0/25174.26.102.1 to 174.26.102.126174.26.102.127126
206174.26.102.128/25174.26.102.129 to 174.26.102.254174.26.102.255126
207174.26.103.0/25174.26.103.1 to 174.26.103.126174.26.103.127126
208174.26.103.128/25174.26.103.129 to 174.26.103.254174.26.103.255126
209174.26.104.0/25174.26.104.1 to 174.26.104.126174.26.104.127126
210174.26.104.128/25174.26.104.129 to 174.26.104.254174.26.104.255126
211174.26.105.0/25174.26.105.1 to 174.26.105.126174.26.105.127126
212174.26.105.128/25174.26.105.129 to 174.26.105.254174.26.105.255126
213174.26.106.0/25174.26.106.1 to 174.26.106.126174.26.106.127126
214174.26.106.128/25174.26.106.129 to 174.26.106.254174.26.106.255126
215174.26.107.0/25174.26.107.1 to 174.26.107.126174.26.107.127126
216174.26.107.128/25174.26.107.129 to 174.26.107.254174.26.107.255126
217174.26.108.0/25174.26.108.1 to 174.26.108.126174.26.108.127126
218174.26.108.128/25174.26.108.129 to 174.26.108.254174.26.108.255126
219174.26.109.0/25174.26.109.1 to 174.26.109.126174.26.109.127126
220174.26.109.128/25174.26.109.129 to 174.26.109.254174.26.109.255126
221174.26.110.0/25174.26.110.1 to 174.26.110.126174.26.110.127126
222174.26.110.128/25174.26.110.129 to 174.26.110.254174.26.110.255126
223174.26.111.0/25174.26.111.1 to 174.26.111.126174.26.111.127126
224174.26.111.128/25174.26.111.129 to 174.26.111.254174.26.111.255126
225174.26.112.0/25174.26.112.1 to 174.26.112.126174.26.112.127126
226174.26.112.128/25174.26.112.129 to 174.26.112.254174.26.112.255126
227174.26.113.0/25174.26.113.1 to 174.26.113.126174.26.113.127126
228174.26.113.128/25174.26.113.129 to 174.26.113.254174.26.113.255126
229174.26.114.0/25174.26.114.1 to 174.26.114.126174.26.114.127126
230174.26.114.128/25174.26.114.129 to 174.26.114.254174.26.114.255126
231174.26.115.0/25174.26.115.1 to 174.26.115.126174.26.115.127126
232174.26.115.128/25174.26.115.129 to 174.26.115.254174.26.115.255126
233174.26.116.0/25174.26.116.1 to 174.26.116.126174.26.116.127126
234174.26.116.128/25174.26.116.129 to 174.26.116.254174.26.116.255126
235174.26.117.0/25174.26.117.1 to 174.26.117.126174.26.117.127126
236174.26.117.128/25174.26.117.129 to 174.26.117.254174.26.117.255126
237174.26.118.0/25174.26.118.1 to 174.26.118.126174.26.118.127126
238174.26.118.128/25174.26.118.129 to 174.26.118.254174.26.118.255126
239174.26.119.0/25174.26.119.1 to 174.26.119.126174.26.119.127126
240174.26.119.128/25174.26.119.129 to 174.26.119.254174.26.119.255126
241174.26.120.0/25174.26.120.1 to 174.26.120.126174.26.120.127126
242174.26.120.128/25174.26.120.129 to 174.26.120.254174.26.120.255126
243174.26.121.0/25174.26.121.1 to 174.26.121.126174.26.121.127126
244174.26.121.128/25174.26.121.129 to 174.26.121.254174.26.121.255126
245174.26.122.0/25174.26.122.1 to 174.26.122.126174.26.122.127126
246174.26.122.128/25174.26.122.129 to 174.26.122.254174.26.122.255126
247174.26.123.0/25174.26.123.1 to 174.26.123.126174.26.123.127126
248174.26.123.128/25174.26.123.129 to 174.26.123.254174.26.123.255126
249174.26.124.0/25174.26.124.1 to 174.26.124.126174.26.124.127126
250174.26.124.128/25174.26.124.129 to 174.26.124.254174.26.124.255126
251174.26.125.0/25174.26.125.1 to 174.26.125.126174.26.125.127126
252174.26.125.128/25174.26.125.129 to 174.26.125.254174.26.125.255126
253174.26.126.0/25174.26.126.1 to 174.26.126.126174.26.126.127126
254174.26.126.128/25174.26.126.129 to 174.26.126.254174.26.126.255126
255174.26.127.0/25174.26.127.1 to 174.26.127.126174.26.127.127126
256174.26.127.128/25174.26.127.129 to 174.26.127.254174.26.127.255126

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.