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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.

Network119.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
119.0.0.0
Broadcast address
119.127.255.255
First usable
119.0.0.1
Last usable
119.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 77000000 · Integer 1996488704 to 2004877311
Reverse DNS zones
0.119.in-addr.arpa
1.119.in-addr.arpa
2.119.in-addr.arpa
3.119.in-addr.arpa
4.119.in-addr.arpa
5.119.in-addr.arpa
6.119.in-addr.arpa
7.119.in-addr.arpa
8.119.in-addr.arpa
9.119.in-addr.arpa
10.119.in-addr.arpa
11.119.in-addr.arpa
12.119.in-addr.arpa
13.119.in-addr.arpa
14.119.in-addr.arpa
15.119.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110111.00000000.00000000.00000000119.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01110111.00000000.00000000.00000000119.0.0.0
Broadcast01110111.01111111.11111111.11111111119.127.255.255
Split into smaller subnets/17
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

119.0.0.0/9 makes 256 subnets of /17.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1119.0.0.0/17119.0.0.1 to 119.0.127.254119.0.127.25532,766
2119.0.128.0/17119.0.128.1 to 119.0.255.254119.0.255.25532,766
3119.1.0.0/17119.1.0.1 to 119.1.127.254119.1.127.25532,766
4119.1.128.0/17119.1.128.1 to 119.1.255.254119.1.255.25532,766
5119.2.0.0/17119.2.0.1 to 119.2.127.254119.2.127.25532,766
6119.2.128.0/17119.2.128.1 to 119.2.255.254119.2.255.25532,766
7119.3.0.0/17119.3.0.1 to 119.3.127.254119.3.127.25532,766
8119.3.128.0/17119.3.128.1 to 119.3.255.254119.3.255.25532,766
9119.4.0.0/17119.4.0.1 to 119.4.127.254119.4.127.25532,766
10119.4.128.0/17119.4.128.1 to 119.4.255.254119.4.255.25532,766
11119.5.0.0/17119.5.0.1 to 119.5.127.254119.5.127.25532,766
12119.5.128.0/17119.5.128.1 to 119.5.255.254119.5.255.25532,766
13119.6.0.0/17119.6.0.1 to 119.6.127.254119.6.127.25532,766
14119.6.128.0/17119.6.128.1 to 119.6.255.254119.6.255.25532,766
15119.7.0.0/17119.7.0.1 to 119.7.127.254119.7.127.25532,766
16119.7.128.0/17119.7.128.1 to 119.7.255.254119.7.255.25532,766
17119.8.0.0/17119.8.0.1 to 119.8.127.254119.8.127.25532,766
18119.8.128.0/17119.8.128.1 to 119.8.255.254119.8.255.25532,766
19119.9.0.0/17119.9.0.1 to 119.9.127.254119.9.127.25532,766
20119.9.128.0/17119.9.128.1 to 119.9.255.254119.9.255.25532,766
21119.10.0.0/17119.10.0.1 to 119.10.127.254119.10.127.25532,766
22119.10.128.0/17119.10.128.1 to 119.10.255.254119.10.255.25532,766
23119.11.0.0/17119.11.0.1 to 119.11.127.254119.11.127.25532,766
24119.11.128.0/17119.11.128.1 to 119.11.255.254119.11.255.25532,766
25119.12.0.0/17119.12.0.1 to 119.12.127.254119.12.127.25532,766
26119.12.128.0/17119.12.128.1 to 119.12.255.254119.12.255.25532,766
27119.13.0.0/17119.13.0.1 to 119.13.127.254119.13.127.25532,766
28119.13.128.0/17119.13.128.1 to 119.13.255.254119.13.255.25532,766
29119.14.0.0/17119.14.0.1 to 119.14.127.254119.14.127.25532,766
30119.14.128.0/17119.14.128.1 to 119.14.255.254119.14.255.25532,766
31119.15.0.0/17119.15.0.1 to 119.15.127.254119.15.127.25532,766
32119.15.128.0/17119.15.128.1 to 119.15.255.254119.15.255.25532,766
33119.16.0.0/17119.16.0.1 to 119.16.127.254119.16.127.25532,766
34119.16.128.0/17119.16.128.1 to 119.16.255.254119.16.255.25532,766
35119.17.0.0/17119.17.0.1 to 119.17.127.254119.17.127.25532,766
36119.17.128.0/17119.17.128.1 to 119.17.255.254119.17.255.25532,766
37119.18.0.0/17119.18.0.1 to 119.18.127.254119.18.127.25532,766
38119.18.128.0/17119.18.128.1 to 119.18.255.254119.18.255.25532,766
39119.19.0.0/17119.19.0.1 to 119.19.127.254119.19.127.25532,766
40119.19.128.0/17119.19.128.1 to 119.19.255.254119.19.255.25532,766
41119.20.0.0/17119.20.0.1 to 119.20.127.254119.20.127.25532,766
42119.20.128.0/17119.20.128.1 to 119.20.255.254119.20.255.25532,766
43119.21.0.0/17119.21.0.1 to 119.21.127.254119.21.127.25532,766
44119.21.128.0/17119.21.128.1 to 119.21.255.254119.21.255.25532,766
45119.22.0.0/17119.22.0.1 to 119.22.127.254119.22.127.25532,766
46119.22.128.0/17119.22.128.1 to 119.22.255.254119.22.255.25532,766
47119.23.0.0/17119.23.0.1 to 119.23.127.254119.23.127.25532,766
48119.23.128.0/17119.23.128.1 to 119.23.255.254119.23.255.25532,766
49119.24.0.0/17119.24.0.1 to 119.24.127.254119.24.127.25532,766
50119.24.128.0/17119.24.128.1 to 119.24.255.254119.24.255.25532,766
51119.25.0.0/17119.25.0.1 to 119.25.127.254119.25.127.25532,766
52119.25.128.0/17119.25.128.1 to 119.25.255.254119.25.255.25532,766
53119.26.0.0/17119.26.0.1 to 119.26.127.254119.26.127.25532,766
54119.26.128.0/17119.26.128.1 to 119.26.255.254119.26.255.25532,766
55119.27.0.0/17119.27.0.1 to 119.27.127.254119.27.127.25532,766
56119.27.128.0/17119.27.128.1 to 119.27.255.254119.27.255.25532,766
57119.28.0.0/17119.28.0.1 to 119.28.127.254119.28.127.25532,766
58119.28.128.0/17119.28.128.1 to 119.28.255.254119.28.255.25532,766
59119.29.0.0/17119.29.0.1 to 119.29.127.254119.29.127.25532,766
60119.29.128.0/17119.29.128.1 to 119.29.255.254119.29.255.25532,766
61119.30.0.0/17119.30.0.1 to 119.30.127.254119.30.127.25532,766
62119.30.128.0/17119.30.128.1 to 119.30.255.254119.30.255.25532,766
63119.31.0.0/17119.31.0.1 to 119.31.127.254119.31.127.25532,766
64119.31.128.0/17119.31.128.1 to 119.31.255.254119.31.255.25532,766
65119.32.0.0/17119.32.0.1 to 119.32.127.254119.32.127.25532,766
66119.32.128.0/17119.32.128.1 to 119.32.255.254119.32.255.25532,766
67119.33.0.0/17119.33.0.1 to 119.33.127.254119.33.127.25532,766
68119.33.128.0/17119.33.128.1 to 119.33.255.254119.33.255.25532,766
69119.34.0.0/17119.34.0.1 to 119.34.127.254119.34.127.25532,766
70119.34.128.0/17119.34.128.1 to 119.34.255.254119.34.255.25532,766
71119.35.0.0/17119.35.0.1 to 119.35.127.254119.35.127.25532,766
72119.35.128.0/17119.35.128.1 to 119.35.255.254119.35.255.25532,766
73119.36.0.0/17119.36.0.1 to 119.36.127.254119.36.127.25532,766
74119.36.128.0/17119.36.128.1 to 119.36.255.254119.36.255.25532,766
75119.37.0.0/17119.37.0.1 to 119.37.127.254119.37.127.25532,766
76119.37.128.0/17119.37.128.1 to 119.37.255.254119.37.255.25532,766
77119.38.0.0/17119.38.0.1 to 119.38.127.254119.38.127.25532,766
78119.38.128.0/17119.38.128.1 to 119.38.255.254119.38.255.25532,766
79119.39.0.0/17119.39.0.1 to 119.39.127.254119.39.127.25532,766
80119.39.128.0/17119.39.128.1 to 119.39.255.254119.39.255.25532,766
81119.40.0.0/17119.40.0.1 to 119.40.127.254119.40.127.25532,766
82119.40.128.0/17119.40.128.1 to 119.40.255.254119.40.255.25532,766
83119.41.0.0/17119.41.0.1 to 119.41.127.254119.41.127.25532,766
84119.41.128.0/17119.41.128.1 to 119.41.255.254119.41.255.25532,766
85119.42.0.0/17119.42.0.1 to 119.42.127.254119.42.127.25532,766
86119.42.128.0/17119.42.128.1 to 119.42.255.254119.42.255.25532,766
87119.43.0.0/17119.43.0.1 to 119.43.127.254119.43.127.25532,766
88119.43.128.0/17119.43.128.1 to 119.43.255.254119.43.255.25532,766
89119.44.0.0/17119.44.0.1 to 119.44.127.254119.44.127.25532,766
90119.44.128.0/17119.44.128.1 to 119.44.255.254119.44.255.25532,766
91119.45.0.0/17119.45.0.1 to 119.45.127.254119.45.127.25532,766
92119.45.128.0/17119.45.128.1 to 119.45.255.254119.45.255.25532,766
93119.46.0.0/17119.46.0.1 to 119.46.127.254119.46.127.25532,766
94119.46.128.0/17119.46.128.1 to 119.46.255.254119.46.255.25532,766
95119.47.0.0/17119.47.0.1 to 119.47.127.254119.47.127.25532,766
96119.47.128.0/17119.47.128.1 to 119.47.255.254119.47.255.25532,766
97119.48.0.0/17119.48.0.1 to 119.48.127.254119.48.127.25532,766
98119.48.128.0/17119.48.128.1 to 119.48.255.254119.48.255.25532,766
99119.49.0.0/17119.49.0.1 to 119.49.127.254119.49.127.25532,766
100119.49.128.0/17119.49.128.1 to 119.49.255.254119.49.255.25532,766
101119.50.0.0/17119.50.0.1 to 119.50.127.254119.50.127.25532,766
102119.50.128.0/17119.50.128.1 to 119.50.255.254119.50.255.25532,766
103119.51.0.0/17119.51.0.1 to 119.51.127.254119.51.127.25532,766
104119.51.128.0/17119.51.128.1 to 119.51.255.254119.51.255.25532,766
105119.52.0.0/17119.52.0.1 to 119.52.127.254119.52.127.25532,766
106119.52.128.0/17119.52.128.1 to 119.52.255.254119.52.255.25532,766
107119.53.0.0/17119.53.0.1 to 119.53.127.254119.53.127.25532,766
108119.53.128.0/17119.53.128.1 to 119.53.255.254119.53.255.25532,766
109119.54.0.0/17119.54.0.1 to 119.54.127.254119.54.127.25532,766
110119.54.128.0/17119.54.128.1 to 119.54.255.254119.54.255.25532,766
111119.55.0.0/17119.55.0.1 to 119.55.127.254119.55.127.25532,766
112119.55.128.0/17119.55.128.1 to 119.55.255.254119.55.255.25532,766
113119.56.0.0/17119.56.0.1 to 119.56.127.254119.56.127.25532,766
114119.56.128.0/17119.56.128.1 to 119.56.255.254119.56.255.25532,766
115119.57.0.0/17119.57.0.1 to 119.57.127.254119.57.127.25532,766
116119.57.128.0/17119.57.128.1 to 119.57.255.254119.57.255.25532,766
117119.58.0.0/17119.58.0.1 to 119.58.127.254119.58.127.25532,766
118119.58.128.0/17119.58.128.1 to 119.58.255.254119.58.255.25532,766
119119.59.0.0/17119.59.0.1 to 119.59.127.254119.59.127.25532,766
120119.59.128.0/17119.59.128.1 to 119.59.255.254119.59.255.25532,766
121119.60.0.0/17119.60.0.1 to 119.60.127.254119.60.127.25532,766
122119.60.128.0/17119.60.128.1 to 119.60.255.254119.60.255.25532,766
123119.61.0.0/17119.61.0.1 to 119.61.127.254119.61.127.25532,766
124119.61.128.0/17119.61.128.1 to 119.61.255.254119.61.255.25532,766
125119.62.0.0/17119.62.0.1 to 119.62.127.254119.62.127.25532,766
126119.62.128.0/17119.62.128.1 to 119.62.255.254119.62.255.25532,766
127119.63.0.0/17119.63.0.1 to 119.63.127.254119.63.127.25532,766
128119.63.128.0/17119.63.128.1 to 119.63.255.254119.63.255.25532,766
129119.64.0.0/17119.64.0.1 to 119.64.127.254119.64.127.25532,766
130119.64.128.0/17119.64.128.1 to 119.64.255.254119.64.255.25532,766
131119.65.0.0/17119.65.0.1 to 119.65.127.254119.65.127.25532,766
132119.65.128.0/17119.65.128.1 to 119.65.255.254119.65.255.25532,766
133119.66.0.0/17119.66.0.1 to 119.66.127.254119.66.127.25532,766
134119.66.128.0/17119.66.128.1 to 119.66.255.254119.66.255.25532,766
135119.67.0.0/17119.67.0.1 to 119.67.127.254119.67.127.25532,766
136119.67.128.0/17119.67.128.1 to 119.67.255.254119.67.255.25532,766
137119.68.0.0/17119.68.0.1 to 119.68.127.254119.68.127.25532,766
138119.68.128.0/17119.68.128.1 to 119.68.255.254119.68.255.25532,766
139119.69.0.0/17119.69.0.1 to 119.69.127.254119.69.127.25532,766
140119.69.128.0/17119.69.128.1 to 119.69.255.254119.69.255.25532,766
141119.70.0.0/17119.70.0.1 to 119.70.127.254119.70.127.25532,766
142119.70.128.0/17119.70.128.1 to 119.70.255.254119.70.255.25532,766
143119.71.0.0/17119.71.0.1 to 119.71.127.254119.71.127.25532,766
144119.71.128.0/17119.71.128.1 to 119.71.255.254119.71.255.25532,766
145119.72.0.0/17119.72.0.1 to 119.72.127.254119.72.127.25532,766
146119.72.128.0/17119.72.128.1 to 119.72.255.254119.72.255.25532,766
147119.73.0.0/17119.73.0.1 to 119.73.127.254119.73.127.25532,766
148119.73.128.0/17119.73.128.1 to 119.73.255.254119.73.255.25532,766
149119.74.0.0/17119.74.0.1 to 119.74.127.254119.74.127.25532,766
150119.74.128.0/17119.74.128.1 to 119.74.255.254119.74.255.25532,766
151119.75.0.0/17119.75.0.1 to 119.75.127.254119.75.127.25532,766
152119.75.128.0/17119.75.128.1 to 119.75.255.254119.75.255.25532,766
153119.76.0.0/17119.76.0.1 to 119.76.127.254119.76.127.25532,766
154119.76.128.0/17119.76.128.1 to 119.76.255.254119.76.255.25532,766
155119.77.0.0/17119.77.0.1 to 119.77.127.254119.77.127.25532,766
156119.77.128.0/17119.77.128.1 to 119.77.255.254119.77.255.25532,766
157119.78.0.0/17119.78.0.1 to 119.78.127.254119.78.127.25532,766
158119.78.128.0/17119.78.128.1 to 119.78.255.254119.78.255.25532,766
159119.79.0.0/17119.79.0.1 to 119.79.127.254119.79.127.25532,766
160119.79.128.0/17119.79.128.1 to 119.79.255.254119.79.255.25532,766
161119.80.0.0/17119.80.0.1 to 119.80.127.254119.80.127.25532,766
162119.80.128.0/17119.80.128.1 to 119.80.255.254119.80.255.25532,766
163119.81.0.0/17119.81.0.1 to 119.81.127.254119.81.127.25532,766
164119.81.128.0/17119.81.128.1 to 119.81.255.254119.81.255.25532,766
165119.82.0.0/17119.82.0.1 to 119.82.127.254119.82.127.25532,766
166119.82.128.0/17119.82.128.1 to 119.82.255.254119.82.255.25532,766
167119.83.0.0/17119.83.0.1 to 119.83.127.254119.83.127.25532,766
168119.83.128.0/17119.83.128.1 to 119.83.255.254119.83.255.25532,766
169119.84.0.0/17119.84.0.1 to 119.84.127.254119.84.127.25532,766
170119.84.128.0/17119.84.128.1 to 119.84.255.254119.84.255.25532,766
171119.85.0.0/17119.85.0.1 to 119.85.127.254119.85.127.25532,766
172119.85.128.0/17119.85.128.1 to 119.85.255.254119.85.255.25532,766
173119.86.0.0/17119.86.0.1 to 119.86.127.254119.86.127.25532,766
174119.86.128.0/17119.86.128.1 to 119.86.255.254119.86.255.25532,766
175119.87.0.0/17119.87.0.1 to 119.87.127.254119.87.127.25532,766
176119.87.128.0/17119.87.128.1 to 119.87.255.254119.87.255.25532,766
177119.88.0.0/17119.88.0.1 to 119.88.127.254119.88.127.25532,766
178119.88.128.0/17119.88.128.1 to 119.88.255.254119.88.255.25532,766
179119.89.0.0/17119.89.0.1 to 119.89.127.254119.89.127.25532,766
180119.89.128.0/17119.89.128.1 to 119.89.255.254119.89.255.25532,766
181119.90.0.0/17119.90.0.1 to 119.90.127.254119.90.127.25532,766
182119.90.128.0/17119.90.128.1 to 119.90.255.254119.90.255.25532,766
183119.91.0.0/17119.91.0.1 to 119.91.127.254119.91.127.25532,766
184119.91.128.0/17119.91.128.1 to 119.91.255.254119.91.255.25532,766
185119.92.0.0/17119.92.0.1 to 119.92.127.254119.92.127.25532,766
186119.92.128.0/17119.92.128.1 to 119.92.255.254119.92.255.25532,766
187119.93.0.0/17119.93.0.1 to 119.93.127.254119.93.127.25532,766
188119.93.128.0/17119.93.128.1 to 119.93.255.254119.93.255.25532,766
189119.94.0.0/17119.94.0.1 to 119.94.127.254119.94.127.25532,766
190119.94.128.0/17119.94.128.1 to 119.94.255.254119.94.255.25532,766
191119.95.0.0/17119.95.0.1 to 119.95.127.254119.95.127.25532,766
192119.95.128.0/17119.95.128.1 to 119.95.255.254119.95.255.25532,766
193119.96.0.0/17119.96.0.1 to 119.96.127.254119.96.127.25532,766
194119.96.128.0/17119.96.128.1 to 119.96.255.254119.96.255.25532,766
195119.97.0.0/17119.97.0.1 to 119.97.127.254119.97.127.25532,766
196119.97.128.0/17119.97.128.1 to 119.97.255.254119.97.255.25532,766
197119.98.0.0/17119.98.0.1 to 119.98.127.254119.98.127.25532,766
198119.98.128.0/17119.98.128.1 to 119.98.255.254119.98.255.25532,766
199119.99.0.0/17119.99.0.1 to 119.99.127.254119.99.127.25532,766
200119.99.128.0/17119.99.128.1 to 119.99.255.254119.99.255.25532,766
201119.100.0.0/17119.100.0.1 to 119.100.127.254119.100.127.25532,766
202119.100.128.0/17119.100.128.1 to 119.100.255.254119.100.255.25532,766
203119.101.0.0/17119.101.0.1 to 119.101.127.254119.101.127.25532,766
204119.101.128.0/17119.101.128.1 to 119.101.255.254119.101.255.25532,766
205119.102.0.0/17119.102.0.1 to 119.102.127.254119.102.127.25532,766
206119.102.128.0/17119.102.128.1 to 119.102.255.254119.102.255.25532,766
207119.103.0.0/17119.103.0.1 to 119.103.127.254119.103.127.25532,766
208119.103.128.0/17119.103.128.1 to 119.103.255.254119.103.255.25532,766
209119.104.0.0/17119.104.0.1 to 119.104.127.254119.104.127.25532,766
210119.104.128.0/17119.104.128.1 to 119.104.255.254119.104.255.25532,766
211119.105.0.0/17119.105.0.1 to 119.105.127.254119.105.127.25532,766
212119.105.128.0/17119.105.128.1 to 119.105.255.254119.105.255.25532,766
213119.106.0.0/17119.106.0.1 to 119.106.127.254119.106.127.25532,766
214119.106.128.0/17119.106.128.1 to 119.106.255.254119.106.255.25532,766
215119.107.0.0/17119.107.0.1 to 119.107.127.254119.107.127.25532,766
216119.107.128.0/17119.107.128.1 to 119.107.255.254119.107.255.25532,766
217119.108.0.0/17119.108.0.1 to 119.108.127.254119.108.127.25532,766
218119.108.128.0/17119.108.128.1 to 119.108.255.254119.108.255.25532,766
219119.109.0.0/17119.109.0.1 to 119.109.127.254119.109.127.25532,766
220119.109.128.0/17119.109.128.1 to 119.109.255.254119.109.255.25532,766
221119.110.0.0/17119.110.0.1 to 119.110.127.254119.110.127.25532,766
222119.110.128.0/17119.110.128.1 to 119.110.255.254119.110.255.25532,766
223119.111.0.0/17119.111.0.1 to 119.111.127.254119.111.127.25532,766
224119.111.128.0/17119.111.128.1 to 119.111.255.254119.111.255.25532,766
225119.112.0.0/17119.112.0.1 to 119.112.127.254119.112.127.25532,766
226119.112.128.0/17119.112.128.1 to 119.112.255.254119.112.255.25532,766
227119.113.0.0/17119.113.0.1 to 119.113.127.254119.113.127.25532,766
228119.113.128.0/17119.113.128.1 to 119.113.255.254119.113.255.25532,766
229119.114.0.0/17119.114.0.1 to 119.114.127.254119.114.127.25532,766
230119.114.128.0/17119.114.128.1 to 119.114.255.254119.114.255.25532,766
231119.115.0.0/17119.115.0.1 to 119.115.127.254119.115.127.25532,766
232119.115.128.0/17119.115.128.1 to 119.115.255.254119.115.255.25532,766
233119.116.0.0/17119.116.0.1 to 119.116.127.254119.116.127.25532,766
234119.116.128.0/17119.116.128.1 to 119.116.255.254119.116.255.25532,766
235119.117.0.0/17119.117.0.1 to 119.117.127.254119.117.127.25532,766
236119.117.128.0/17119.117.128.1 to 119.117.255.254119.117.255.25532,766
237119.118.0.0/17119.118.0.1 to 119.118.127.254119.118.127.25532,766
238119.118.128.0/17119.118.128.1 to 119.118.255.254119.118.255.25532,766
239119.119.0.0/17119.119.0.1 to 119.119.127.254119.119.127.25532,766
240119.119.128.0/17119.119.128.1 to 119.119.255.254119.119.255.25532,766
241119.120.0.0/17119.120.0.1 to 119.120.127.254119.120.127.25532,766
242119.120.128.0/17119.120.128.1 to 119.120.255.254119.120.255.25532,766
243119.121.0.0/17119.121.0.1 to 119.121.127.254119.121.127.25532,766
244119.121.128.0/17119.121.128.1 to 119.121.255.254119.121.255.25532,766
245119.122.0.0/17119.122.0.1 to 119.122.127.254119.122.127.25532,766
246119.122.128.0/17119.122.128.1 to 119.122.255.254119.122.255.25532,766
247119.123.0.0/17119.123.0.1 to 119.123.127.254119.123.127.25532,766
248119.123.128.0/17119.123.128.1 to 119.123.255.254119.123.255.25532,766
249119.124.0.0/17119.124.0.1 to 119.124.127.254119.124.127.25532,766
250119.124.128.0/17119.124.128.1 to 119.124.255.254119.124.255.25532,766
251119.125.0.0/17119.125.0.1 to 119.125.127.254119.125.127.25532,766
252119.125.128.0/17119.125.128.1 to 119.125.255.254119.125.255.25532,766
253119.126.0.0/17119.126.0.1 to 119.126.127.254119.126.127.25532,766
254119.126.128.0/17119.126.128.1 to 119.126.255.254119.126.255.25532,766
255119.127.0.0/17119.127.0.1 to 119.127.127.254119.127.127.25532,766
256119.127.128.0/17119.127.128.1 to 119.127.255.254119.127.255.25532,766

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.