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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.

Network174.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
174.0.0.0
Broadcast address
175.255.255.255
First usable
174.0.0.1
Last usable
175.255.255.254
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 AE000000 · Integer 2919235584 to 2952790015
Reverse DNS zones
174.in-addr.arpa
175.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
Address10101110.00000000.00000000.00000000174.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10101110.00000000.00000000.00000000174.0.0.0
Broadcast10101111.11111111.11111111.11111111175.255.255.255
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)

174.0.0.0/7 makes 1,024 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1174.0.0.0/17174.0.0.1 to 174.0.127.254174.0.127.25532,766
2174.0.128.0/17174.0.128.1 to 174.0.255.254174.0.255.25532,766
3174.1.0.0/17174.1.0.1 to 174.1.127.254174.1.127.25532,766
4174.1.128.0/17174.1.128.1 to 174.1.255.254174.1.255.25532,766
5174.2.0.0/17174.2.0.1 to 174.2.127.254174.2.127.25532,766
6174.2.128.0/17174.2.128.1 to 174.2.255.254174.2.255.25532,766
7174.3.0.0/17174.3.0.1 to 174.3.127.254174.3.127.25532,766
8174.3.128.0/17174.3.128.1 to 174.3.255.254174.3.255.25532,766
9174.4.0.0/17174.4.0.1 to 174.4.127.254174.4.127.25532,766
10174.4.128.0/17174.4.128.1 to 174.4.255.254174.4.255.25532,766
11174.5.0.0/17174.5.0.1 to 174.5.127.254174.5.127.25532,766
12174.5.128.0/17174.5.128.1 to 174.5.255.254174.5.255.25532,766
13174.6.0.0/17174.6.0.1 to 174.6.127.254174.6.127.25532,766
14174.6.128.0/17174.6.128.1 to 174.6.255.254174.6.255.25532,766
15174.7.0.0/17174.7.0.1 to 174.7.127.254174.7.127.25532,766
16174.7.128.0/17174.7.128.1 to 174.7.255.254174.7.255.25532,766
17174.8.0.0/17174.8.0.1 to 174.8.127.254174.8.127.25532,766
18174.8.128.0/17174.8.128.1 to 174.8.255.254174.8.255.25532,766
19174.9.0.0/17174.9.0.1 to 174.9.127.254174.9.127.25532,766
20174.9.128.0/17174.9.128.1 to 174.9.255.254174.9.255.25532,766
21174.10.0.0/17174.10.0.1 to 174.10.127.254174.10.127.25532,766
22174.10.128.0/17174.10.128.1 to 174.10.255.254174.10.255.25532,766
23174.11.0.0/17174.11.0.1 to 174.11.127.254174.11.127.25532,766
24174.11.128.0/17174.11.128.1 to 174.11.255.254174.11.255.25532,766
25174.12.0.0/17174.12.0.1 to 174.12.127.254174.12.127.25532,766
26174.12.128.0/17174.12.128.1 to 174.12.255.254174.12.255.25532,766
27174.13.0.0/17174.13.0.1 to 174.13.127.254174.13.127.25532,766
28174.13.128.0/17174.13.128.1 to 174.13.255.254174.13.255.25532,766
29174.14.0.0/17174.14.0.1 to 174.14.127.254174.14.127.25532,766
30174.14.128.0/17174.14.128.1 to 174.14.255.254174.14.255.25532,766
31174.15.0.0/17174.15.0.1 to 174.15.127.254174.15.127.25532,766
32174.15.128.0/17174.15.128.1 to 174.15.255.254174.15.255.25532,766
33174.16.0.0/17174.16.0.1 to 174.16.127.254174.16.127.25532,766
34174.16.128.0/17174.16.128.1 to 174.16.255.254174.16.255.25532,766
35174.17.0.0/17174.17.0.1 to 174.17.127.254174.17.127.25532,766
36174.17.128.0/17174.17.128.1 to 174.17.255.254174.17.255.25532,766
37174.18.0.0/17174.18.0.1 to 174.18.127.254174.18.127.25532,766
38174.18.128.0/17174.18.128.1 to 174.18.255.254174.18.255.25532,766
39174.19.0.0/17174.19.0.1 to 174.19.127.254174.19.127.25532,766
40174.19.128.0/17174.19.128.1 to 174.19.255.254174.19.255.25532,766
41174.20.0.0/17174.20.0.1 to 174.20.127.254174.20.127.25532,766
42174.20.128.0/17174.20.128.1 to 174.20.255.254174.20.255.25532,766
43174.21.0.0/17174.21.0.1 to 174.21.127.254174.21.127.25532,766
44174.21.128.0/17174.21.128.1 to 174.21.255.254174.21.255.25532,766
45174.22.0.0/17174.22.0.1 to 174.22.127.254174.22.127.25532,766
46174.22.128.0/17174.22.128.1 to 174.22.255.254174.22.255.25532,766
47174.23.0.0/17174.23.0.1 to 174.23.127.254174.23.127.25532,766
48174.23.128.0/17174.23.128.1 to 174.23.255.254174.23.255.25532,766
49174.24.0.0/17174.24.0.1 to 174.24.127.254174.24.127.25532,766
50174.24.128.0/17174.24.128.1 to 174.24.255.254174.24.255.25532,766
51174.25.0.0/17174.25.0.1 to 174.25.127.254174.25.127.25532,766
52174.25.128.0/17174.25.128.1 to 174.25.255.254174.25.255.25532,766
53174.26.0.0/17174.26.0.1 to 174.26.127.254174.26.127.25532,766
54174.26.128.0/17174.26.128.1 to 174.26.255.254174.26.255.25532,766
55174.27.0.0/17174.27.0.1 to 174.27.127.254174.27.127.25532,766
56174.27.128.0/17174.27.128.1 to 174.27.255.254174.27.255.25532,766
57174.28.0.0/17174.28.0.1 to 174.28.127.254174.28.127.25532,766
58174.28.128.0/17174.28.128.1 to 174.28.255.254174.28.255.25532,766
59174.29.0.0/17174.29.0.1 to 174.29.127.254174.29.127.25532,766
60174.29.128.0/17174.29.128.1 to 174.29.255.254174.29.255.25532,766
61174.30.0.0/17174.30.0.1 to 174.30.127.254174.30.127.25532,766
62174.30.128.0/17174.30.128.1 to 174.30.255.254174.30.255.25532,766
63174.31.0.0/17174.31.0.1 to 174.31.127.254174.31.127.25532,766
64174.31.128.0/17174.31.128.1 to 174.31.255.254174.31.255.25532,766
65174.32.0.0/17174.32.0.1 to 174.32.127.254174.32.127.25532,766
66174.32.128.0/17174.32.128.1 to 174.32.255.254174.32.255.25532,766
67174.33.0.0/17174.33.0.1 to 174.33.127.254174.33.127.25532,766
68174.33.128.0/17174.33.128.1 to 174.33.255.254174.33.255.25532,766
69174.34.0.0/17174.34.0.1 to 174.34.127.254174.34.127.25532,766
70174.34.128.0/17174.34.128.1 to 174.34.255.254174.34.255.25532,766
71174.35.0.0/17174.35.0.1 to 174.35.127.254174.35.127.25532,766
72174.35.128.0/17174.35.128.1 to 174.35.255.254174.35.255.25532,766
73174.36.0.0/17174.36.0.1 to 174.36.127.254174.36.127.25532,766
74174.36.128.0/17174.36.128.1 to 174.36.255.254174.36.255.25532,766
75174.37.0.0/17174.37.0.1 to 174.37.127.254174.37.127.25532,766
76174.37.128.0/17174.37.128.1 to 174.37.255.254174.37.255.25532,766
77174.38.0.0/17174.38.0.1 to 174.38.127.254174.38.127.25532,766
78174.38.128.0/17174.38.128.1 to 174.38.255.254174.38.255.25532,766
79174.39.0.0/17174.39.0.1 to 174.39.127.254174.39.127.25532,766
80174.39.128.0/17174.39.128.1 to 174.39.255.254174.39.255.25532,766
81174.40.0.0/17174.40.0.1 to 174.40.127.254174.40.127.25532,766
82174.40.128.0/17174.40.128.1 to 174.40.255.254174.40.255.25532,766
83174.41.0.0/17174.41.0.1 to 174.41.127.254174.41.127.25532,766
84174.41.128.0/17174.41.128.1 to 174.41.255.254174.41.255.25532,766
85174.42.0.0/17174.42.0.1 to 174.42.127.254174.42.127.25532,766
86174.42.128.0/17174.42.128.1 to 174.42.255.254174.42.255.25532,766
87174.43.0.0/17174.43.0.1 to 174.43.127.254174.43.127.25532,766
88174.43.128.0/17174.43.128.1 to 174.43.255.254174.43.255.25532,766
89174.44.0.0/17174.44.0.1 to 174.44.127.254174.44.127.25532,766
90174.44.128.0/17174.44.128.1 to 174.44.255.254174.44.255.25532,766
91174.45.0.0/17174.45.0.1 to 174.45.127.254174.45.127.25532,766
92174.45.128.0/17174.45.128.1 to 174.45.255.254174.45.255.25532,766
93174.46.0.0/17174.46.0.1 to 174.46.127.254174.46.127.25532,766
94174.46.128.0/17174.46.128.1 to 174.46.255.254174.46.255.25532,766
95174.47.0.0/17174.47.0.1 to 174.47.127.254174.47.127.25532,766
96174.47.128.0/17174.47.128.1 to 174.47.255.254174.47.255.25532,766
97174.48.0.0/17174.48.0.1 to 174.48.127.254174.48.127.25532,766
98174.48.128.0/17174.48.128.1 to 174.48.255.254174.48.255.25532,766
99174.49.0.0/17174.49.0.1 to 174.49.127.254174.49.127.25532,766
100174.49.128.0/17174.49.128.1 to 174.49.255.254174.49.255.25532,766
101174.50.0.0/17174.50.0.1 to 174.50.127.254174.50.127.25532,766
102174.50.128.0/17174.50.128.1 to 174.50.255.254174.50.255.25532,766
103174.51.0.0/17174.51.0.1 to 174.51.127.254174.51.127.25532,766
104174.51.128.0/17174.51.128.1 to 174.51.255.254174.51.255.25532,766
105174.52.0.0/17174.52.0.1 to 174.52.127.254174.52.127.25532,766
106174.52.128.0/17174.52.128.1 to 174.52.255.254174.52.255.25532,766
107174.53.0.0/17174.53.0.1 to 174.53.127.254174.53.127.25532,766
108174.53.128.0/17174.53.128.1 to 174.53.255.254174.53.255.25532,766
109174.54.0.0/17174.54.0.1 to 174.54.127.254174.54.127.25532,766
110174.54.128.0/17174.54.128.1 to 174.54.255.254174.54.255.25532,766
111174.55.0.0/17174.55.0.1 to 174.55.127.254174.55.127.25532,766
112174.55.128.0/17174.55.128.1 to 174.55.255.254174.55.255.25532,766
113174.56.0.0/17174.56.0.1 to 174.56.127.254174.56.127.25532,766
114174.56.128.0/17174.56.128.1 to 174.56.255.254174.56.255.25532,766
115174.57.0.0/17174.57.0.1 to 174.57.127.254174.57.127.25532,766
116174.57.128.0/17174.57.128.1 to 174.57.255.254174.57.255.25532,766
117174.58.0.0/17174.58.0.1 to 174.58.127.254174.58.127.25532,766
118174.58.128.0/17174.58.128.1 to 174.58.255.254174.58.255.25532,766
119174.59.0.0/17174.59.0.1 to 174.59.127.254174.59.127.25532,766
120174.59.128.0/17174.59.128.1 to 174.59.255.254174.59.255.25532,766
121174.60.0.0/17174.60.0.1 to 174.60.127.254174.60.127.25532,766
122174.60.128.0/17174.60.128.1 to 174.60.255.254174.60.255.25532,766
123174.61.0.0/17174.61.0.1 to 174.61.127.254174.61.127.25532,766
124174.61.128.0/17174.61.128.1 to 174.61.255.254174.61.255.25532,766
125174.62.0.0/17174.62.0.1 to 174.62.127.254174.62.127.25532,766
126174.62.128.0/17174.62.128.1 to 174.62.255.254174.62.255.25532,766
127174.63.0.0/17174.63.0.1 to 174.63.127.254174.63.127.25532,766
128174.63.128.0/17174.63.128.1 to 174.63.255.254174.63.255.25532,766
129174.64.0.0/17174.64.0.1 to 174.64.127.254174.64.127.25532,766
130174.64.128.0/17174.64.128.1 to 174.64.255.254174.64.255.25532,766
131174.65.0.0/17174.65.0.1 to 174.65.127.254174.65.127.25532,766
132174.65.128.0/17174.65.128.1 to 174.65.255.254174.65.255.25532,766
133174.66.0.0/17174.66.0.1 to 174.66.127.254174.66.127.25532,766
134174.66.128.0/17174.66.128.1 to 174.66.255.254174.66.255.25532,766
135174.67.0.0/17174.67.0.1 to 174.67.127.254174.67.127.25532,766
136174.67.128.0/17174.67.128.1 to 174.67.255.254174.67.255.25532,766
137174.68.0.0/17174.68.0.1 to 174.68.127.254174.68.127.25532,766
138174.68.128.0/17174.68.128.1 to 174.68.255.254174.68.255.25532,766
139174.69.0.0/17174.69.0.1 to 174.69.127.254174.69.127.25532,766
140174.69.128.0/17174.69.128.1 to 174.69.255.254174.69.255.25532,766
141174.70.0.0/17174.70.0.1 to 174.70.127.254174.70.127.25532,766
142174.70.128.0/17174.70.128.1 to 174.70.255.254174.70.255.25532,766
143174.71.0.0/17174.71.0.1 to 174.71.127.254174.71.127.25532,766
144174.71.128.0/17174.71.128.1 to 174.71.255.254174.71.255.25532,766
145174.72.0.0/17174.72.0.1 to 174.72.127.254174.72.127.25532,766
146174.72.128.0/17174.72.128.1 to 174.72.255.254174.72.255.25532,766
147174.73.0.0/17174.73.0.1 to 174.73.127.254174.73.127.25532,766
148174.73.128.0/17174.73.128.1 to 174.73.255.254174.73.255.25532,766
149174.74.0.0/17174.74.0.1 to 174.74.127.254174.74.127.25532,766
150174.74.128.0/17174.74.128.1 to 174.74.255.254174.74.255.25532,766
151174.75.0.0/17174.75.0.1 to 174.75.127.254174.75.127.25532,766
152174.75.128.0/17174.75.128.1 to 174.75.255.254174.75.255.25532,766
153174.76.0.0/17174.76.0.1 to 174.76.127.254174.76.127.25532,766
154174.76.128.0/17174.76.128.1 to 174.76.255.254174.76.255.25532,766
155174.77.0.0/17174.77.0.1 to 174.77.127.254174.77.127.25532,766
156174.77.128.0/17174.77.128.1 to 174.77.255.254174.77.255.25532,766
157174.78.0.0/17174.78.0.1 to 174.78.127.254174.78.127.25532,766
158174.78.128.0/17174.78.128.1 to 174.78.255.254174.78.255.25532,766
159174.79.0.0/17174.79.0.1 to 174.79.127.254174.79.127.25532,766
160174.79.128.0/17174.79.128.1 to 174.79.255.254174.79.255.25532,766
161174.80.0.0/17174.80.0.1 to 174.80.127.254174.80.127.25532,766
162174.80.128.0/17174.80.128.1 to 174.80.255.254174.80.255.25532,766
163174.81.0.0/17174.81.0.1 to 174.81.127.254174.81.127.25532,766
164174.81.128.0/17174.81.128.1 to 174.81.255.254174.81.255.25532,766
165174.82.0.0/17174.82.0.1 to 174.82.127.254174.82.127.25532,766
166174.82.128.0/17174.82.128.1 to 174.82.255.254174.82.255.25532,766
167174.83.0.0/17174.83.0.1 to 174.83.127.254174.83.127.25532,766
168174.83.128.0/17174.83.128.1 to 174.83.255.254174.83.255.25532,766
169174.84.0.0/17174.84.0.1 to 174.84.127.254174.84.127.25532,766
170174.84.128.0/17174.84.128.1 to 174.84.255.254174.84.255.25532,766
171174.85.0.0/17174.85.0.1 to 174.85.127.254174.85.127.25532,766
172174.85.128.0/17174.85.128.1 to 174.85.255.254174.85.255.25532,766
173174.86.0.0/17174.86.0.1 to 174.86.127.254174.86.127.25532,766
174174.86.128.0/17174.86.128.1 to 174.86.255.254174.86.255.25532,766
175174.87.0.0/17174.87.0.1 to 174.87.127.254174.87.127.25532,766
176174.87.128.0/17174.87.128.1 to 174.87.255.254174.87.255.25532,766
177174.88.0.0/17174.88.0.1 to 174.88.127.254174.88.127.25532,766
178174.88.128.0/17174.88.128.1 to 174.88.255.254174.88.255.25532,766
179174.89.0.0/17174.89.0.1 to 174.89.127.254174.89.127.25532,766
180174.89.128.0/17174.89.128.1 to 174.89.255.254174.89.255.25532,766
181174.90.0.0/17174.90.0.1 to 174.90.127.254174.90.127.25532,766
182174.90.128.0/17174.90.128.1 to 174.90.255.254174.90.255.25532,766
183174.91.0.0/17174.91.0.1 to 174.91.127.254174.91.127.25532,766
184174.91.128.0/17174.91.128.1 to 174.91.255.254174.91.255.25532,766
185174.92.0.0/17174.92.0.1 to 174.92.127.254174.92.127.25532,766
186174.92.128.0/17174.92.128.1 to 174.92.255.254174.92.255.25532,766
187174.93.0.0/17174.93.0.1 to 174.93.127.254174.93.127.25532,766
188174.93.128.0/17174.93.128.1 to 174.93.255.254174.93.255.25532,766
189174.94.0.0/17174.94.0.1 to 174.94.127.254174.94.127.25532,766
190174.94.128.0/17174.94.128.1 to 174.94.255.254174.94.255.25532,766
191174.95.0.0/17174.95.0.1 to 174.95.127.254174.95.127.25532,766
192174.95.128.0/17174.95.128.1 to 174.95.255.254174.95.255.25532,766
193174.96.0.0/17174.96.0.1 to 174.96.127.254174.96.127.25532,766
194174.96.128.0/17174.96.128.1 to 174.96.255.254174.96.255.25532,766
195174.97.0.0/17174.97.0.1 to 174.97.127.254174.97.127.25532,766
196174.97.128.0/17174.97.128.1 to 174.97.255.254174.97.255.25532,766
197174.98.0.0/17174.98.0.1 to 174.98.127.254174.98.127.25532,766
198174.98.128.0/17174.98.128.1 to 174.98.255.254174.98.255.25532,766
199174.99.0.0/17174.99.0.1 to 174.99.127.254174.99.127.25532,766
200174.99.128.0/17174.99.128.1 to 174.99.255.254174.99.255.25532,766
201174.100.0.0/17174.100.0.1 to 174.100.127.254174.100.127.25532,766
202174.100.128.0/17174.100.128.1 to 174.100.255.254174.100.255.25532,766
203174.101.0.0/17174.101.0.1 to 174.101.127.254174.101.127.25532,766
204174.101.128.0/17174.101.128.1 to 174.101.255.254174.101.255.25532,766
205174.102.0.0/17174.102.0.1 to 174.102.127.254174.102.127.25532,766
206174.102.128.0/17174.102.128.1 to 174.102.255.254174.102.255.25532,766
207174.103.0.0/17174.103.0.1 to 174.103.127.254174.103.127.25532,766
208174.103.128.0/17174.103.128.1 to 174.103.255.254174.103.255.25532,766
209174.104.0.0/17174.104.0.1 to 174.104.127.254174.104.127.25532,766
210174.104.128.0/17174.104.128.1 to 174.104.255.254174.104.255.25532,766
211174.105.0.0/17174.105.0.1 to 174.105.127.254174.105.127.25532,766
212174.105.128.0/17174.105.128.1 to 174.105.255.254174.105.255.25532,766
213174.106.0.0/17174.106.0.1 to 174.106.127.254174.106.127.25532,766
214174.106.128.0/17174.106.128.1 to 174.106.255.254174.106.255.25532,766
215174.107.0.0/17174.107.0.1 to 174.107.127.254174.107.127.25532,766
216174.107.128.0/17174.107.128.1 to 174.107.255.254174.107.255.25532,766
217174.108.0.0/17174.108.0.1 to 174.108.127.254174.108.127.25532,766
218174.108.128.0/17174.108.128.1 to 174.108.255.254174.108.255.25532,766
219174.109.0.0/17174.109.0.1 to 174.109.127.254174.109.127.25532,766
220174.109.128.0/17174.109.128.1 to 174.109.255.254174.109.255.25532,766
221174.110.0.0/17174.110.0.1 to 174.110.127.254174.110.127.25532,766
222174.110.128.0/17174.110.128.1 to 174.110.255.254174.110.255.25532,766
223174.111.0.0/17174.111.0.1 to 174.111.127.254174.111.127.25532,766
224174.111.128.0/17174.111.128.1 to 174.111.255.254174.111.255.25532,766
225174.112.0.0/17174.112.0.1 to 174.112.127.254174.112.127.25532,766
226174.112.128.0/17174.112.128.1 to 174.112.255.254174.112.255.25532,766
227174.113.0.0/17174.113.0.1 to 174.113.127.254174.113.127.25532,766
228174.113.128.0/17174.113.128.1 to 174.113.255.254174.113.255.25532,766
229174.114.0.0/17174.114.0.1 to 174.114.127.254174.114.127.25532,766
230174.114.128.0/17174.114.128.1 to 174.114.255.254174.114.255.25532,766
231174.115.0.0/17174.115.0.1 to 174.115.127.254174.115.127.25532,766
232174.115.128.0/17174.115.128.1 to 174.115.255.254174.115.255.25532,766
233174.116.0.0/17174.116.0.1 to 174.116.127.254174.116.127.25532,766
234174.116.128.0/17174.116.128.1 to 174.116.255.254174.116.255.25532,766
235174.117.0.0/17174.117.0.1 to 174.117.127.254174.117.127.25532,766
236174.117.128.0/17174.117.128.1 to 174.117.255.254174.117.255.25532,766
237174.118.0.0/17174.118.0.1 to 174.118.127.254174.118.127.25532,766
238174.118.128.0/17174.118.128.1 to 174.118.255.254174.118.255.25532,766
239174.119.0.0/17174.119.0.1 to 174.119.127.254174.119.127.25532,766
240174.119.128.0/17174.119.128.1 to 174.119.255.254174.119.255.25532,766
241174.120.0.0/17174.120.0.1 to 174.120.127.254174.120.127.25532,766
242174.120.128.0/17174.120.128.1 to 174.120.255.254174.120.255.25532,766
243174.121.0.0/17174.121.0.1 to 174.121.127.254174.121.127.25532,766
244174.121.128.0/17174.121.128.1 to 174.121.255.254174.121.255.25532,766
245174.122.0.0/17174.122.0.1 to 174.122.127.254174.122.127.25532,766
246174.122.128.0/17174.122.128.1 to 174.122.255.254174.122.255.25532,766
247174.123.0.0/17174.123.0.1 to 174.123.127.254174.123.127.25532,766
248174.123.128.0/17174.123.128.1 to 174.123.255.254174.123.255.25532,766
249174.124.0.0/17174.124.0.1 to 174.124.127.254174.124.127.25532,766
250174.124.128.0/17174.124.128.1 to 174.124.255.254174.124.255.25532,766
251174.125.0.0/17174.125.0.1 to 174.125.127.254174.125.127.25532,766
252174.125.128.0/17174.125.128.1 to 174.125.255.254174.125.255.25532,766
253174.126.0.0/17174.126.0.1 to 174.126.127.254174.126.127.25532,766
254174.126.128.0/17174.126.128.1 to 174.126.255.254174.126.255.25532,766
255174.127.0.0/17174.127.0.1 to 174.127.127.254174.127.127.25532,766
256174.127.128.0/17174.127.128.1 to 174.127.255.254174.127.255.25532,766

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.