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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.

Network110.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
110.0.0.0
Broadcast address
110.127.255.255
First usable
110.0.0.1
Last usable
110.127.255.254
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 6E000000 · Integer 1845493760 to 1853882367
Reverse DNS zones
0.110.in-addr.arpa
1.110.in-addr.arpa
2.110.in-addr.arpa
3.110.in-addr.arpa
4.110.in-addr.arpa
5.110.in-addr.arpa
6.110.in-addr.arpa
7.110.in-addr.arpa
8.110.in-addr.arpa
9.110.in-addr.arpa
10.110.in-addr.arpa
11.110.in-addr.arpa
12.110.in-addr.arpa
13.110.in-addr.arpa
14.110.in-addr.arpa
15.110.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
Address01101110.00000000.00000000.00000000110.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01101110.00000000.00000000.00000000110.0.0.0
Broadcast01101110.01111111.11111111.11111111110.127.255.255
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)

110.0.0.0/9 makes 256 subnets of /17.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1110.0.0.0/17110.0.0.1 to 110.0.127.254110.0.127.25532,766
2110.0.128.0/17110.0.128.1 to 110.0.255.254110.0.255.25532,766
3110.1.0.0/17110.1.0.1 to 110.1.127.254110.1.127.25532,766
4110.1.128.0/17110.1.128.1 to 110.1.255.254110.1.255.25532,766
5110.2.0.0/17110.2.0.1 to 110.2.127.254110.2.127.25532,766
6110.2.128.0/17110.2.128.1 to 110.2.255.254110.2.255.25532,766
7110.3.0.0/17110.3.0.1 to 110.3.127.254110.3.127.25532,766
8110.3.128.0/17110.3.128.1 to 110.3.255.254110.3.255.25532,766
9110.4.0.0/17110.4.0.1 to 110.4.127.254110.4.127.25532,766
10110.4.128.0/17110.4.128.1 to 110.4.255.254110.4.255.25532,766
11110.5.0.0/17110.5.0.1 to 110.5.127.254110.5.127.25532,766
12110.5.128.0/17110.5.128.1 to 110.5.255.254110.5.255.25532,766
13110.6.0.0/17110.6.0.1 to 110.6.127.254110.6.127.25532,766
14110.6.128.0/17110.6.128.1 to 110.6.255.254110.6.255.25532,766
15110.7.0.0/17110.7.0.1 to 110.7.127.254110.7.127.25532,766
16110.7.128.0/17110.7.128.1 to 110.7.255.254110.7.255.25532,766
17110.8.0.0/17110.8.0.1 to 110.8.127.254110.8.127.25532,766
18110.8.128.0/17110.8.128.1 to 110.8.255.254110.8.255.25532,766
19110.9.0.0/17110.9.0.1 to 110.9.127.254110.9.127.25532,766
20110.9.128.0/17110.9.128.1 to 110.9.255.254110.9.255.25532,766
21110.10.0.0/17110.10.0.1 to 110.10.127.254110.10.127.25532,766
22110.10.128.0/17110.10.128.1 to 110.10.255.254110.10.255.25532,766
23110.11.0.0/17110.11.0.1 to 110.11.127.254110.11.127.25532,766
24110.11.128.0/17110.11.128.1 to 110.11.255.254110.11.255.25532,766
25110.12.0.0/17110.12.0.1 to 110.12.127.254110.12.127.25532,766
26110.12.128.0/17110.12.128.1 to 110.12.255.254110.12.255.25532,766
27110.13.0.0/17110.13.0.1 to 110.13.127.254110.13.127.25532,766
28110.13.128.0/17110.13.128.1 to 110.13.255.254110.13.255.25532,766
29110.14.0.0/17110.14.0.1 to 110.14.127.254110.14.127.25532,766
30110.14.128.0/17110.14.128.1 to 110.14.255.254110.14.255.25532,766
31110.15.0.0/17110.15.0.1 to 110.15.127.254110.15.127.25532,766
32110.15.128.0/17110.15.128.1 to 110.15.255.254110.15.255.25532,766
33110.16.0.0/17110.16.0.1 to 110.16.127.254110.16.127.25532,766
34110.16.128.0/17110.16.128.1 to 110.16.255.254110.16.255.25532,766
35110.17.0.0/17110.17.0.1 to 110.17.127.254110.17.127.25532,766
36110.17.128.0/17110.17.128.1 to 110.17.255.254110.17.255.25532,766
37110.18.0.0/17110.18.0.1 to 110.18.127.254110.18.127.25532,766
38110.18.128.0/17110.18.128.1 to 110.18.255.254110.18.255.25532,766
39110.19.0.0/17110.19.0.1 to 110.19.127.254110.19.127.25532,766
40110.19.128.0/17110.19.128.1 to 110.19.255.254110.19.255.25532,766
41110.20.0.0/17110.20.0.1 to 110.20.127.254110.20.127.25532,766
42110.20.128.0/17110.20.128.1 to 110.20.255.254110.20.255.25532,766
43110.21.0.0/17110.21.0.1 to 110.21.127.254110.21.127.25532,766
44110.21.128.0/17110.21.128.1 to 110.21.255.254110.21.255.25532,766
45110.22.0.0/17110.22.0.1 to 110.22.127.254110.22.127.25532,766
46110.22.128.0/17110.22.128.1 to 110.22.255.254110.22.255.25532,766
47110.23.0.0/17110.23.0.1 to 110.23.127.254110.23.127.25532,766
48110.23.128.0/17110.23.128.1 to 110.23.255.254110.23.255.25532,766
49110.24.0.0/17110.24.0.1 to 110.24.127.254110.24.127.25532,766
50110.24.128.0/17110.24.128.1 to 110.24.255.254110.24.255.25532,766
51110.25.0.0/17110.25.0.1 to 110.25.127.254110.25.127.25532,766
52110.25.128.0/17110.25.128.1 to 110.25.255.254110.25.255.25532,766
53110.26.0.0/17110.26.0.1 to 110.26.127.254110.26.127.25532,766
54110.26.128.0/17110.26.128.1 to 110.26.255.254110.26.255.25532,766
55110.27.0.0/17110.27.0.1 to 110.27.127.254110.27.127.25532,766
56110.27.128.0/17110.27.128.1 to 110.27.255.254110.27.255.25532,766
57110.28.0.0/17110.28.0.1 to 110.28.127.254110.28.127.25532,766
58110.28.128.0/17110.28.128.1 to 110.28.255.254110.28.255.25532,766
59110.29.0.0/17110.29.0.1 to 110.29.127.254110.29.127.25532,766
60110.29.128.0/17110.29.128.1 to 110.29.255.254110.29.255.25532,766
61110.30.0.0/17110.30.0.1 to 110.30.127.254110.30.127.25532,766
62110.30.128.0/17110.30.128.1 to 110.30.255.254110.30.255.25532,766
63110.31.0.0/17110.31.0.1 to 110.31.127.254110.31.127.25532,766
64110.31.128.0/17110.31.128.1 to 110.31.255.254110.31.255.25532,766
65110.32.0.0/17110.32.0.1 to 110.32.127.254110.32.127.25532,766
66110.32.128.0/17110.32.128.1 to 110.32.255.254110.32.255.25532,766
67110.33.0.0/17110.33.0.1 to 110.33.127.254110.33.127.25532,766
68110.33.128.0/17110.33.128.1 to 110.33.255.254110.33.255.25532,766
69110.34.0.0/17110.34.0.1 to 110.34.127.254110.34.127.25532,766
70110.34.128.0/17110.34.128.1 to 110.34.255.254110.34.255.25532,766
71110.35.0.0/17110.35.0.1 to 110.35.127.254110.35.127.25532,766
72110.35.128.0/17110.35.128.1 to 110.35.255.254110.35.255.25532,766
73110.36.0.0/17110.36.0.1 to 110.36.127.254110.36.127.25532,766
74110.36.128.0/17110.36.128.1 to 110.36.255.254110.36.255.25532,766
75110.37.0.0/17110.37.0.1 to 110.37.127.254110.37.127.25532,766
76110.37.128.0/17110.37.128.1 to 110.37.255.254110.37.255.25532,766
77110.38.0.0/17110.38.0.1 to 110.38.127.254110.38.127.25532,766
78110.38.128.0/17110.38.128.1 to 110.38.255.254110.38.255.25532,766
79110.39.0.0/17110.39.0.1 to 110.39.127.254110.39.127.25532,766
80110.39.128.0/17110.39.128.1 to 110.39.255.254110.39.255.25532,766
81110.40.0.0/17110.40.0.1 to 110.40.127.254110.40.127.25532,766
82110.40.128.0/17110.40.128.1 to 110.40.255.254110.40.255.25532,766
83110.41.0.0/17110.41.0.1 to 110.41.127.254110.41.127.25532,766
84110.41.128.0/17110.41.128.1 to 110.41.255.254110.41.255.25532,766
85110.42.0.0/17110.42.0.1 to 110.42.127.254110.42.127.25532,766
86110.42.128.0/17110.42.128.1 to 110.42.255.254110.42.255.25532,766
87110.43.0.0/17110.43.0.1 to 110.43.127.254110.43.127.25532,766
88110.43.128.0/17110.43.128.1 to 110.43.255.254110.43.255.25532,766
89110.44.0.0/17110.44.0.1 to 110.44.127.254110.44.127.25532,766
90110.44.128.0/17110.44.128.1 to 110.44.255.254110.44.255.25532,766
91110.45.0.0/17110.45.0.1 to 110.45.127.254110.45.127.25532,766
92110.45.128.0/17110.45.128.1 to 110.45.255.254110.45.255.25532,766
93110.46.0.0/17110.46.0.1 to 110.46.127.254110.46.127.25532,766
94110.46.128.0/17110.46.128.1 to 110.46.255.254110.46.255.25532,766
95110.47.0.0/17110.47.0.1 to 110.47.127.254110.47.127.25532,766
96110.47.128.0/17110.47.128.1 to 110.47.255.254110.47.255.25532,766
97110.48.0.0/17110.48.0.1 to 110.48.127.254110.48.127.25532,766
98110.48.128.0/17110.48.128.1 to 110.48.255.254110.48.255.25532,766
99110.49.0.0/17110.49.0.1 to 110.49.127.254110.49.127.25532,766
100110.49.128.0/17110.49.128.1 to 110.49.255.254110.49.255.25532,766
101110.50.0.0/17110.50.0.1 to 110.50.127.254110.50.127.25532,766
102110.50.128.0/17110.50.128.1 to 110.50.255.254110.50.255.25532,766
103110.51.0.0/17110.51.0.1 to 110.51.127.254110.51.127.25532,766
104110.51.128.0/17110.51.128.1 to 110.51.255.254110.51.255.25532,766
105110.52.0.0/17110.52.0.1 to 110.52.127.254110.52.127.25532,766
106110.52.128.0/17110.52.128.1 to 110.52.255.254110.52.255.25532,766
107110.53.0.0/17110.53.0.1 to 110.53.127.254110.53.127.25532,766
108110.53.128.0/17110.53.128.1 to 110.53.255.254110.53.255.25532,766
109110.54.0.0/17110.54.0.1 to 110.54.127.254110.54.127.25532,766
110110.54.128.0/17110.54.128.1 to 110.54.255.254110.54.255.25532,766
111110.55.0.0/17110.55.0.1 to 110.55.127.254110.55.127.25532,766
112110.55.128.0/17110.55.128.1 to 110.55.255.254110.55.255.25532,766
113110.56.0.0/17110.56.0.1 to 110.56.127.254110.56.127.25532,766
114110.56.128.0/17110.56.128.1 to 110.56.255.254110.56.255.25532,766
115110.57.0.0/17110.57.0.1 to 110.57.127.254110.57.127.25532,766
116110.57.128.0/17110.57.128.1 to 110.57.255.254110.57.255.25532,766
117110.58.0.0/17110.58.0.1 to 110.58.127.254110.58.127.25532,766
118110.58.128.0/17110.58.128.1 to 110.58.255.254110.58.255.25532,766
119110.59.0.0/17110.59.0.1 to 110.59.127.254110.59.127.25532,766
120110.59.128.0/17110.59.128.1 to 110.59.255.254110.59.255.25532,766
121110.60.0.0/17110.60.0.1 to 110.60.127.254110.60.127.25532,766
122110.60.128.0/17110.60.128.1 to 110.60.255.254110.60.255.25532,766
123110.61.0.0/17110.61.0.1 to 110.61.127.254110.61.127.25532,766
124110.61.128.0/17110.61.128.1 to 110.61.255.254110.61.255.25532,766
125110.62.0.0/17110.62.0.1 to 110.62.127.254110.62.127.25532,766
126110.62.128.0/17110.62.128.1 to 110.62.255.254110.62.255.25532,766
127110.63.0.0/17110.63.0.1 to 110.63.127.254110.63.127.25532,766
128110.63.128.0/17110.63.128.1 to 110.63.255.254110.63.255.25532,766
129110.64.0.0/17110.64.0.1 to 110.64.127.254110.64.127.25532,766
130110.64.128.0/17110.64.128.1 to 110.64.255.254110.64.255.25532,766
131110.65.0.0/17110.65.0.1 to 110.65.127.254110.65.127.25532,766
132110.65.128.0/17110.65.128.1 to 110.65.255.254110.65.255.25532,766
133110.66.0.0/17110.66.0.1 to 110.66.127.254110.66.127.25532,766
134110.66.128.0/17110.66.128.1 to 110.66.255.254110.66.255.25532,766
135110.67.0.0/17110.67.0.1 to 110.67.127.254110.67.127.25532,766
136110.67.128.0/17110.67.128.1 to 110.67.255.254110.67.255.25532,766
137110.68.0.0/17110.68.0.1 to 110.68.127.254110.68.127.25532,766
138110.68.128.0/17110.68.128.1 to 110.68.255.254110.68.255.25532,766
139110.69.0.0/17110.69.0.1 to 110.69.127.254110.69.127.25532,766
140110.69.128.0/17110.69.128.1 to 110.69.255.254110.69.255.25532,766
141110.70.0.0/17110.70.0.1 to 110.70.127.254110.70.127.25532,766
142110.70.128.0/17110.70.128.1 to 110.70.255.254110.70.255.25532,766
143110.71.0.0/17110.71.0.1 to 110.71.127.254110.71.127.25532,766
144110.71.128.0/17110.71.128.1 to 110.71.255.254110.71.255.25532,766
145110.72.0.0/17110.72.0.1 to 110.72.127.254110.72.127.25532,766
146110.72.128.0/17110.72.128.1 to 110.72.255.254110.72.255.25532,766
147110.73.0.0/17110.73.0.1 to 110.73.127.254110.73.127.25532,766
148110.73.128.0/17110.73.128.1 to 110.73.255.254110.73.255.25532,766
149110.74.0.0/17110.74.0.1 to 110.74.127.254110.74.127.25532,766
150110.74.128.0/17110.74.128.1 to 110.74.255.254110.74.255.25532,766
151110.75.0.0/17110.75.0.1 to 110.75.127.254110.75.127.25532,766
152110.75.128.0/17110.75.128.1 to 110.75.255.254110.75.255.25532,766
153110.76.0.0/17110.76.0.1 to 110.76.127.254110.76.127.25532,766
154110.76.128.0/17110.76.128.1 to 110.76.255.254110.76.255.25532,766
155110.77.0.0/17110.77.0.1 to 110.77.127.254110.77.127.25532,766
156110.77.128.0/17110.77.128.1 to 110.77.255.254110.77.255.25532,766
157110.78.0.0/17110.78.0.1 to 110.78.127.254110.78.127.25532,766
158110.78.128.0/17110.78.128.1 to 110.78.255.254110.78.255.25532,766
159110.79.0.0/17110.79.0.1 to 110.79.127.254110.79.127.25532,766
160110.79.128.0/17110.79.128.1 to 110.79.255.254110.79.255.25532,766
161110.80.0.0/17110.80.0.1 to 110.80.127.254110.80.127.25532,766
162110.80.128.0/17110.80.128.1 to 110.80.255.254110.80.255.25532,766
163110.81.0.0/17110.81.0.1 to 110.81.127.254110.81.127.25532,766
164110.81.128.0/17110.81.128.1 to 110.81.255.254110.81.255.25532,766
165110.82.0.0/17110.82.0.1 to 110.82.127.254110.82.127.25532,766
166110.82.128.0/17110.82.128.1 to 110.82.255.254110.82.255.25532,766
167110.83.0.0/17110.83.0.1 to 110.83.127.254110.83.127.25532,766
168110.83.128.0/17110.83.128.1 to 110.83.255.254110.83.255.25532,766
169110.84.0.0/17110.84.0.1 to 110.84.127.254110.84.127.25532,766
170110.84.128.0/17110.84.128.1 to 110.84.255.254110.84.255.25532,766
171110.85.0.0/17110.85.0.1 to 110.85.127.254110.85.127.25532,766
172110.85.128.0/17110.85.128.1 to 110.85.255.254110.85.255.25532,766
173110.86.0.0/17110.86.0.1 to 110.86.127.254110.86.127.25532,766
174110.86.128.0/17110.86.128.1 to 110.86.255.254110.86.255.25532,766
175110.87.0.0/17110.87.0.1 to 110.87.127.254110.87.127.25532,766
176110.87.128.0/17110.87.128.1 to 110.87.255.254110.87.255.25532,766
177110.88.0.0/17110.88.0.1 to 110.88.127.254110.88.127.25532,766
178110.88.128.0/17110.88.128.1 to 110.88.255.254110.88.255.25532,766
179110.89.0.0/17110.89.0.1 to 110.89.127.254110.89.127.25532,766
180110.89.128.0/17110.89.128.1 to 110.89.255.254110.89.255.25532,766
181110.90.0.0/17110.90.0.1 to 110.90.127.254110.90.127.25532,766
182110.90.128.0/17110.90.128.1 to 110.90.255.254110.90.255.25532,766
183110.91.0.0/17110.91.0.1 to 110.91.127.254110.91.127.25532,766
184110.91.128.0/17110.91.128.1 to 110.91.255.254110.91.255.25532,766
185110.92.0.0/17110.92.0.1 to 110.92.127.254110.92.127.25532,766
186110.92.128.0/17110.92.128.1 to 110.92.255.254110.92.255.25532,766
187110.93.0.0/17110.93.0.1 to 110.93.127.254110.93.127.25532,766
188110.93.128.0/17110.93.128.1 to 110.93.255.254110.93.255.25532,766
189110.94.0.0/17110.94.0.1 to 110.94.127.254110.94.127.25532,766
190110.94.128.0/17110.94.128.1 to 110.94.255.254110.94.255.25532,766
191110.95.0.0/17110.95.0.1 to 110.95.127.254110.95.127.25532,766
192110.95.128.0/17110.95.128.1 to 110.95.255.254110.95.255.25532,766
193110.96.0.0/17110.96.0.1 to 110.96.127.254110.96.127.25532,766
194110.96.128.0/17110.96.128.1 to 110.96.255.254110.96.255.25532,766
195110.97.0.0/17110.97.0.1 to 110.97.127.254110.97.127.25532,766
196110.97.128.0/17110.97.128.1 to 110.97.255.254110.97.255.25532,766
197110.98.0.0/17110.98.0.1 to 110.98.127.254110.98.127.25532,766
198110.98.128.0/17110.98.128.1 to 110.98.255.254110.98.255.25532,766
199110.99.0.0/17110.99.0.1 to 110.99.127.254110.99.127.25532,766
200110.99.128.0/17110.99.128.1 to 110.99.255.254110.99.255.25532,766
201110.100.0.0/17110.100.0.1 to 110.100.127.254110.100.127.25532,766
202110.100.128.0/17110.100.128.1 to 110.100.255.254110.100.255.25532,766
203110.101.0.0/17110.101.0.1 to 110.101.127.254110.101.127.25532,766
204110.101.128.0/17110.101.128.1 to 110.101.255.254110.101.255.25532,766
205110.102.0.0/17110.102.0.1 to 110.102.127.254110.102.127.25532,766
206110.102.128.0/17110.102.128.1 to 110.102.255.254110.102.255.25532,766
207110.103.0.0/17110.103.0.1 to 110.103.127.254110.103.127.25532,766
208110.103.128.0/17110.103.128.1 to 110.103.255.254110.103.255.25532,766
209110.104.0.0/17110.104.0.1 to 110.104.127.254110.104.127.25532,766
210110.104.128.0/17110.104.128.1 to 110.104.255.254110.104.255.25532,766
211110.105.0.0/17110.105.0.1 to 110.105.127.254110.105.127.25532,766
212110.105.128.0/17110.105.128.1 to 110.105.255.254110.105.255.25532,766
213110.106.0.0/17110.106.0.1 to 110.106.127.254110.106.127.25532,766
214110.106.128.0/17110.106.128.1 to 110.106.255.254110.106.255.25532,766
215110.107.0.0/17110.107.0.1 to 110.107.127.254110.107.127.25532,766
216110.107.128.0/17110.107.128.1 to 110.107.255.254110.107.255.25532,766
217110.108.0.0/17110.108.0.1 to 110.108.127.254110.108.127.25532,766
218110.108.128.0/17110.108.128.1 to 110.108.255.254110.108.255.25532,766
219110.109.0.0/17110.109.0.1 to 110.109.127.254110.109.127.25532,766
220110.109.128.0/17110.109.128.1 to 110.109.255.254110.109.255.25532,766
221110.110.0.0/17110.110.0.1 to 110.110.127.254110.110.127.25532,766
222110.110.128.0/17110.110.128.1 to 110.110.255.254110.110.255.25532,766
223110.111.0.0/17110.111.0.1 to 110.111.127.254110.111.127.25532,766
224110.111.128.0/17110.111.128.1 to 110.111.255.254110.111.255.25532,766
225110.112.0.0/17110.112.0.1 to 110.112.127.254110.112.127.25532,766
226110.112.128.0/17110.112.128.1 to 110.112.255.254110.112.255.25532,766
227110.113.0.0/17110.113.0.1 to 110.113.127.254110.113.127.25532,766
228110.113.128.0/17110.113.128.1 to 110.113.255.254110.113.255.25532,766
229110.114.0.0/17110.114.0.1 to 110.114.127.254110.114.127.25532,766
230110.114.128.0/17110.114.128.1 to 110.114.255.254110.114.255.25532,766
231110.115.0.0/17110.115.0.1 to 110.115.127.254110.115.127.25532,766
232110.115.128.0/17110.115.128.1 to 110.115.255.254110.115.255.25532,766
233110.116.0.0/17110.116.0.1 to 110.116.127.254110.116.127.25532,766
234110.116.128.0/17110.116.128.1 to 110.116.255.254110.116.255.25532,766
235110.117.0.0/17110.117.0.1 to 110.117.127.254110.117.127.25532,766
236110.117.128.0/17110.117.128.1 to 110.117.255.254110.117.255.25532,766
237110.118.0.0/17110.118.0.1 to 110.118.127.254110.118.127.25532,766
238110.118.128.0/17110.118.128.1 to 110.118.255.254110.118.255.25532,766
239110.119.0.0/17110.119.0.1 to 110.119.127.254110.119.127.25532,766
240110.119.128.0/17110.119.128.1 to 110.119.255.254110.119.255.25532,766
241110.120.0.0/17110.120.0.1 to 110.120.127.254110.120.127.25532,766
242110.120.128.0/17110.120.128.1 to 110.120.255.254110.120.255.25532,766
243110.121.0.0/17110.121.0.1 to 110.121.127.254110.121.127.25532,766
244110.121.128.0/17110.121.128.1 to 110.121.255.254110.121.255.25532,766
245110.122.0.0/17110.122.0.1 to 110.122.127.254110.122.127.25532,766
246110.122.128.0/17110.122.128.1 to 110.122.255.254110.122.255.25532,766
247110.123.0.0/17110.123.0.1 to 110.123.127.254110.123.127.25532,766
248110.123.128.0/17110.123.128.1 to 110.123.255.254110.123.255.25532,766
249110.124.0.0/17110.124.0.1 to 110.124.127.254110.124.127.25532,766
250110.124.128.0/17110.124.128.1 to 110.124.255.254110.124.255.25532,766
251110.125.0.0/17110.125.0.1 to 110.125.127.254110.125.127.25532,766
252110.125.128.0/17110.125.128.1 to 110.125.255.254110.125.255.25532,766
253110.126.0.0/17110.126.0.1 to 110.126.127.254110.126.127.25532,766
254110.126.128.0/17110.126.128.1 to 110.126.255.254110.126.255.25532,766
255110.127.0.0/17110.127.0.1 to 110.127.127.254110.127.127.25532,766
256110.127.128.0/17110.127.128.1 to 110.127.255.254110.127.255.25532,766

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.