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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.

Network116.89.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
116.89.0.0
Broadcast address
116.89.255.255
First usable
116.89.0.1
Last usable
116.89.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 74590000 · Integer 1951989760 to 1952055295
Reverse DNS zone
89.116.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110100.01011001..00000000.00000000116.89.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01110100.01011001..00000000.00000000116.89.0.0
Broadcast01110100.01011001..11111111.11111111116.89.255.255
Split into smaller subnets/25
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

116.89.0.0/16 makes 512 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1116.89.0.0/25116.89.0.1 to 116.89.0.126116.89.0.127126
2116.89.0.128/25116.89.0.129 to 116.89.0.254116.89.0.255126
3116.89.1.0/25116.89.1.1 to 116.89.1.126116.89.1.127126
4116.89.1.128/25116.89.1.129 to 116.89.1.254116.89.1.255126
5116.89.2.0/25116.89.2.1 to 116.89.2.126116.89.2.127126
6116.89.2.128/25116.89.2.129 to 116.89.2.254116.89.2.255126
7116.89.3.0/25116.89.3.1 to 116.89.3.126116.89.3.127126
8116.89.3.128/25116.89.3.129 to 116.89.3.254116.89.3.255126
9116.89.4.0/25116.89.4.1 to 116.89.4.126116.89.4.127126
10116.89.4.128/25116.89.4.129 to 116.89.4.254116.89.4.255126
11116.89.5.0/25116.89.5.1 to 116.89.5.126116.89.5.127126
12116.89.5.128/25116.89.5.129 to 116.89.5.254116.89.5.255126
13116.89.6.0/25116.89.6.1 to 116.89.6.126116.89.6.127126
14116.89.6.128/25116.89.6.129 to 116.89.6.254116.89.6.255126
15116.89.7.0/25116.89.7.1 to 116.89.7.126116.89.7.127126
16116.89.7.128/25116.89.7.129 to 116.89.7.254116.89.7.255126
17116.89.8.0/25116.89.8.1 to 116.89.8.126116.89.8.127126
18116.89.8.128/25116.89.8.129 to 116.89.8.254116.89.8.255126
19116.89.9.0/25116.89.9.1 to 116.89.9.126116.89.9.127126
20116.89.9.128/25116.89.9.129 to 116.89.9.254116.89.9.255126
21116.89.10.0/25116.89.10.1 to 116.89.10.126116.89.10.127126
22116.89.10.128/25116.89.10.129 to 116.89.10.254116.89.10.255126
23116.89.11.0/25116.89.11.1 to 116.89.11.126116.89.11.127126
24116.89.11.128/25116.89.11.129 to 116.89.11.254116.89.11.255126
25116.89.12.0/25116.89.12.1 to 116.89.12.126116.89.12.127126
26116.89.12.128/25116.89.12.129 to 116.89.12.254116.89.12.255126
27116.89.13.0/25116.89.13.1 to 116.89.13.126116.89.13.127126
28116.89.13.128/25116.89.13.129 to 116.89.13.254116.89.13.255126
29116.89.14.0/25116.89.14.1 to 116.89.14.126116.89.14.127126
30116.89.14.128/25116.89.14.129 to 116.89.14.254116.89.14.255126
31116.89.15.0/25116.89.15.1 to 116.89.15.126116.89.15.127126
32116.89.15.128/25116.89.15.129 to 116.89.15.254116.89.15.255126
33116.89.16.0/25116.89.16.1 to 116.89.16.126116.89.16.127126
34116.89.16.128/25116.89.16.129 to 116.89.16.254116.89.16.255126
35116.89.17.0/25116.89.17.1 to 116.89.17.126116.89.17.127126
36116.89.17.128/25116.89.17.129 to 116.89.17.254116.89.17.255126
37116.89.18.0/25116.89.18.1 to 116.89.18.126116.89.18.127126
38116.89.18.128/25116.89.18.129 to 116.89.18.254116.89.18.255126
39116.89.19.0/25116.89.19.1 to 116.89.19.126116.89.19.127126
40116.89.19.128/25116.89.19.129 to 116.89.19.254116.89.19.255126
41116.89.20.0/25116.89.20.1 to 116.89.20.126116.89.20.127126
42116.89.20.128/25116.89.20.129 to 116.89.20.254116.89.20.255126
43116.89.21.0/25116.89.21.1 to 116.89.21.126116.89.21.127126
44116.89.21.128/25116.89.21.129 to 116.89.21.254116.89.21.255126
45116.89.22.0/25116.89.22.1 to 116.89.22.126116.89.22.127126
46116.89.22.128/25116.89.22.129 to 116.89.22.254116.89.22.255126
47116.89.23.0/25116.89.23.1 to 116.89.23.126116.89.23.127126
48116.89.23.128/25116.89.23.129 to 116.89.23.254116.89.23.255126
49116.89.24.0/25116.89.24.1 to 116.89.24.126116.89.24.127126
50116.89.24.128/25116.89.24.129 to 116.89.24.254116.89.24.255126
51116.89.25.0/25116.89.25.1 to 116.89.25.126116.89.25.127126
52116.89.25.128/25116.89.25.129 to 116.89.25.254116.89.25.255126
53116.89.26.0/25116.89.26.1 to 116.89.26.126116.89.26.127126
54116.89.26.128/25116.89.26.129 to 116.89.26.254116.89.26.255126
55116.89.27.0/25116.89.27.1 to 116.89.27.126116.89.27.127126
56116.89.27.128/25116.89.27.129 to 116.89.27.254116.89.27.255126
57116.89.28.0/25116.89.28.1 to 116.89.28.126116.89.28.127126
58116.89.28.128/25116.89.28.129 to 116.89.28.254116.89.28.255126
59116.89.29.0/25116.89.29.1 to 116.89.29.126116.89.29.127126
60116.89.29.128/25116.89.29.129 to 116.89.29.254116.89.29.255126
61116.89.30.0/25116.89.30.1 to 116.89.30.126116.89.30.127126
62116.89.30.128/25116.89.30.129 to 116.89.30.254116.89.30.255126
63116.89.31.0/25116.89.31.1 to 116.89.31.126116.89.31.127126
64116.89.31.128/25116.89.31.129 to 116.89.31.254116.89.31.255126
65116.89.32.0/25116.89.32.1 to 116.89.32.126116.89.32.127126
66116.89.32.128/25116.89.32.129 to 116.89.32.254116.89.32.255126
67116.89.33.0/25116.89.33.1 to 116.89.33.126116.89.33.127126
68116.89.33.128/25116.89.33.129 to 116.89.33.254116.89.33.255126
69116.89.34.0/25116.89.34.1 to 116.89.34.126116.89.34.127126
70116.89.34.128/25116.89.34.129 to 116.89.34.254116.89.34.255126
71116.89.35.0/25116.89.35.1 to 116.89.35.126116.89.35.127126
72116.89.35.128/25116.89.35.129 to 116.89.35.254116.89.35.255126
73116.89.36.0/25116.89.36.1 to 116.89.36.126116.89.36.127126
74116.89.36.128/25116.89.36.129 to 116.89.36.254116.89.36.255126
75116.89.37.0/25116.89.37.1 to 116.89.37.126116.89.37.127126
76116.89.37.128/25116.89.37.129 to 116.89.37.254116.89.37.255126
77116.89.38.0/25116.89.38.1 to 116.89.38.126116.89.38.127126
78116.89.38.128/25116.89.38.129 to 116.89.38.254116.89.38.255126
79116.89.39.0/25116.89.39.1 to 116.89.39.126116.89.39.127126
80116.89.39.128/25116.89.39.129 to 116.89.39.254116.89.39.255126
81116.89.40.0/25116.89.40.1 to 116.89.40.126116.89.40.127126
82116.89.40.128/25116.89.40.129 to 116.89.40.254116.89.40.255126
83116.89.41.0/25116.89.41.1 to 116.89.41.126116.89.41.127126
84116.89.41.128/25116.89.41.129 to 116.89.41.254116.89.41.255126
85116.89.42.0/25116.89.42.1 to 116.89.42.126116.89.42.127126
86116.89.42.128/25116.89.42.129 to 116.89.42.254116.89.42.255126
87116.89.43.0/25116.89.43.1 to 116.89.43.126116.89.43.127126
88116.89.43.128/25116.89.43.129 to 116.89.43.254116.89.43.255126
89116.89.44.0/25116.89.44.1 to 116.89.44.126116.89.44.127126
90116.89.44.128/25116.89.44.129 to 116.89.44.254116.89.44.255126
91116.89.45.0/25116.89.45.1 to 116.89.45.126116.89.45.127126
92116.89.45.128/25116.89.45.129 to 116.89.45.254116.89.45.255126
93116.89.46.0/25116.89.46.1 to 116.89.46.126116.89.46.127126
94116.89.46.128/25116.89.46.129 to 116.89.46.254116.89.46.255126
95116.89.47.0/25116.89.47.1 to 116.89.47.126116.89.47.127126
96116.89.47.128/25116.89.47.129 to 116.89.47.254116.89.47.255126
97116.89.48.0/25116.89.48.1 to 116.89.48.126116.89.48.127126
98116.89.48.128/25116.89.48.129 to 116.89.48.254116.89.48.255126
99116.89.49.0/25116.89.49.1 to 116.89.49.126116.89.49.127126
100116.89.49.128/25116.89.49.129 to 116.89.49.254116.89.49.255126
101116.89.50.0/25116.89.50.1 to 116.89.50.126116.89.50.127126
102116.89.50.128/25116.89.50.129 to 116.89.50.254116.89.50.255126
103116.89.51.0/25116.89.51.1 to 116.89.51.126116.89.51.127126
104116.89.51.128/25116.89.51.129 to 116.89.51.254116.89.51.255126
105116.89.52.0/25116.89.52.1 to 116.89.52.126116.89.52.127126
106116.89.52.128/25116.89.52.129 to 116.89.52.254116.89.52.255126
107116.89.53.0/25116.89.53.1 to 116.89.53.126116.89.53.127126
108116.89.53.128/25116.89.53.129 to 116.89.53.254116.89.53.255126
109116.89.54.0/25116.89.54.1 to 116.89.54.126116.89.54.127126
110116.89.54.128/25116.89.54.129 to 116.89.54.254116.89.54.255126
111116.89.55.0/25116.89.55.1 to 116.89.55.126116.89.55.127126
112116.89.55.128/25116.89.55.129 to 116.89.55.254116.89.55.255126
113116.89.56.0/25116.89.56.1 to 116.89.56.126116.89.56.127126
114116.89.56.128/25116.89.56.129 to 116.89.56.254116.89.56.255126
115116.89.57.0/25116.89.57.1 to 116.89.57.126116.89.57.127126
116116.89.57.128/25116.89.57.129 to 116.89.57.254116.89.57.255126
117116.89.58.0/25116.89.58.1 to 116.89.58.126116.89.58.127126
118116.89.58.128/25116.89.58.129 to 116.89.58.254116.89.58.255126
119116.89.59.0/25116.89.59.1 to 116.89.59.126116.89.59.127126
120116.89.59.128/25116.89.59.129 to 116.89.59.254116.89.59.255126
121116.89.60.0/25116.89.60.1 to 116.89.60.126116.89.60.127126
122116.89.60.128/25116.89.60.129 to 116.89.60.254116.89.60.255126
123116.89.61.0/25116.89.61.1 to 116.89.61.126116.89.61.127126
124116.89.61.128/25116.89.61.129 to 116.89.61.254116.89.61.255126
125116.89.62.0/25116.89.62.1 to 116.89.62.126116.89.62.127126
126116.89.62.128/25116.89.62.129 to 116.89.62.254116.89.62.255126
127116.89.63.0/25116.89.63.1 to 116.89.63.126116.89.63.127126
128116.89.63.128/25116.89.63.129 to 116.89.63.254116.89.63.255126
129116.89.64.0/25116.89.64.1 to 116.89.64.126116.89.64.127126
130116.89.64.128/25116.89.64.129 to 116.89.64.254116.89.64.255126
131116.89.65.0/25116.89.65.1 to 116.89.65.126116.89.65.127126
132116.89.65.128/25116.89.65.129 to 116.89.65.254116.89.65.255126
133116.89.66.0/25116.89.66.1 to 116.89.66.126116.89.66.127126
134116.89.66.128/25116.89.66.129 to 116.89.66.254116.89.66.255126
135116.89.67.0/25116.89.67.1 to 116.89.67.126116.89.67.127126
136116.89.67.128/25116.89.67.129 to 116.89.67.254116.89.67.255126
137116.89.68.0/25116.89.68.1 to 116.89.68.126116.89.68.127126
138116.89.68.128/25116.89.68.129 to 116.89.68.254116.89.68.255126
139116.89.69.0/25116.89.69.1 to 116.89.69.126116.89.69.127126
140116.89.69.128/25116.89.69.129 to 116.89.69.254116.89.69.255126
141116.89.70.0/25116.89.70.1 to 116.89.70.126116.89.70.127126
142116.89.70.128/25116.89.70.129 to 116.89.70.254116.89.70.255126
143116.89.71.0/25116.89.71.1 to 116.89.71.126116.89.71.127126
144116.89.71.128/25116.89.71.129 to 116.89.71.254116.89.71.255126
145116.89.72.0/25116.89.72.1 to 116.89.72.126116.89.72.127126
146116.89.72.128/25116.89.72.129 to 116.89.72.254116.89.72.255126
147116.89.73.0/25116.89.73.1 to 116.89.73.126116.89.73.127126
148116.89.73.128/25116.89.73.129 to 116.89.73.254116.89.73.255126
149116.89.74.0/25116.89.74.1 to 116.89.74.126116.89.74.127126
150116.89.74.128/25116.89.74.129 to 116.89.74.254116.89.74.255126
151116.89.75.0/25116.89.75.1 to 116.89.75.126116.89.75.127126
152116.89.75.128/25116.89.75.129 to 116.89.75.254116.89.75.255126
153116.89.76.0/25116.89.76.1 to 116.89.76.126116.89.76.127126
154116.89.76.128/25116.89.76.129 to 116.89.76.254116.89.76.255126
155116.89.77.0/25116.89.77.1 to 116.89.77.126116.89.77.127126
156116.89.77.128/25116.89.77.129 to 116.89.77.254116.89.77.255126
157116.89.78.0/25116.89.78.1 to 116.89.78.126116.89.78.127126
158116.89.78.128/25116.89.78.129 to 116.89.78.254116.89.78.255126
159116.89.79.0/25116.89.79.1 to 116.89.79.126116.89.79.127126
160116.89.79.128/25116.89.79.129 to 116.89.79.254116.89.79.255126
161116.89.80.0/25116.89.80.1 to 116.89.80.126116.89.80.127126
162116.89.80.128/25116.89.80.129 to 116.89.80.254116.89.80.255126
163116.89.81.0/25116.89.81.1 to 116.89.81.126116.89.81.127126
164116.89.81.128/25116.89.81.129 to 116.89.81.254116.89.81.255126
165116.89.82.0/25116.89.82.1 to 116.89.82.126116.89.82.127126
166116.89.82.128/25116.89.82.129 to 116.89.82.254116.89.82.255126
167116.89.83.0/25116.89.83.1 to 116.89.83.126116.89.83.127126
168116.89.83.128/25116.89.83.129 to 116.89.83.254116.89.83.255126
169116.89.84.0/25116.89.84.1 to 116.89.84.126116.89.84.127126
170116.89.84.128/25116.89.84.129 to 116.89.84.254116.89.84.255126
171116.89.85.0/25116.89.85.1 to 116.89.85.126116.89.85.127126
172116.89.85.128/25116.89.85.129 to 116.89.85.254116.89.85.255126
173116.89.86.0/25116.89.86.1 to 116.89.86.126116.89.86.127126
174116.89.86.128/25116.89.86.129 to 116.89.86.254116.89.86.255126
175116.89.87.0/25116.89.87.1 to 116.89.87.126116.89.87.127126
176116.89.87.128/25116.89.87.129 to 116.89.87.254116.89.87.255126
177116.89.88.0/25116.89.88.1 to 116.89.88.126116.89.88.127126
178116.89.88.128/25116.89.88.129 to 116.89.88.254116.89.88.255126
179116.89.89.0/25116.89.89.1 to 116.89.89.126116.89.89.127126
180116.89.89.128/25116.89.89.129 to 116.89.89.254116.89.89.255126
181116.89.90.0/25116.89.90.1 to 116.89.90.126116.89.90.127126
182116.89.90.128/25116.89.90.129 to 116.89.90.254116.89.90.255126
183116.89.91.0/25116.89.91.1 to 116.89.91.126116.89.91.127126
184116.89.91.128/25116.89.91.129 to 116.89.91.254116.89.91.255126
185116.89.92.0/25116.89.92.1 to 116.89.92.126116.89.92.127126
186116.89.92.128/25116.89.92.129 to 116.89.92.254116.89.92.255126
187116.89.93.0/25116.89.93.1 to 116.89.93.126116.89.93.127126
188116.89.93.128/25116.89.93.129 to 116.89.93.254116.89.93.255126
189116.89.94.0/25116.89.94.1 to 116.89.94.126116.89.94.127126
190116.89.94.128/25116.89.94.129 to 116.89.94.254116.89.94.255126
191116.89.95.0/25116.89.95.1 to 116.89.95.126116.89.95.127126
192116.89.95.128/25116.89.95.129 to 116.89.95.254116.89.95.255126
193116.89.96.0/25116.89.96.1 to 116.89.96.126116.89.96.127126
194116.89.96.128/25116.89.96.129 to 116.89.96.254116.89.96.255126
195116.89.97.0/25116.89.97.1 to 116.89.97.126116.89.97.127126
196116.89.97.128/25116.89.97.129 to 116.89.97.254116.89.97.255126
197116.89.98.0/25116.89.98.1 to 116.89.98.126116.89.98.127126
198116.89.98.128/25116.89.98.129 to 116.89.98.254116.89.98.255126
199116.89.99.0/25116.89.99.1 to 116.89.99.126116.89.99.127126
200116.89.99.128/25116.89.99.129 to 116.89.99.254116.89.99.255126
201116.89.100.0/25116.89.100.1 to 116.89.100.126116.89.100.127126
202116.89.100.128/25116.89.100.129 to 116.89.100.254116.89.100.255126
203116.89.101.0/25116.89.101.1 to 116.89.101.126116.89.101.127126
204116.89.101.128/25116.89.101.129 to 116.89.101.254116.89.101.255126
205116.89.102.0/25116.89.102.1 to 116.89.102.126116.89.102.127126
206116.89.102.128/25116.89.102.129 to 116.89.102.254116.89.102.255126
207116.89.103.0/25116.89.103.1 to 116.89.103.126116.89.103.127126
208116.89.103.128/25116.89.103.129 to 116.89.103.254116.89.103.255126
209116.89.104.0/25116.89.104.1 to 116.89.104.126116.89.104.127126
210116.89.104.128/25116.89.104.129 to 116.89.104.254116.89.104.255126
211116.89.105.0/25116.89.105.1 to 116.89.105.126116.89.105.127126
212116.89.105.128/25116.89.105.129 to 116.89.105.254116.89.105.255126
213116.89.106.0/25116.89.106.1 to 116.89.106.126116.89.106.127126
214116.89.106.128/25116.89.106.129 to 116.89.106.254116.89.106.255126
215116.89.107.0/25116.89.107.1 to 116.89.107.126116.89.107.127126
216116.89.107.128/25116.89.107.129 to 116.89.107.254116.89.107.255126
217116.89.108.0/25116.89.108.1 to 116.89.108.126116.89.108.127126
218116.89.108.128/25116.89.108.129 to 116.89.108.254116.89.108.255126
219116.89.109.0/25116.89.109.1 to 116.89.109.126116.89.109.127126
220116.89.109.128/25116.89.109.129 to 116.89.109.254116.89.109.255126
221116.89.110.0/25116.89.110.1 to 116.89.110.126116.89.110.127126
222116.89.110.128/25116.89.110.129 to 116.89.110.254116.89.110.255126
223116.89.111.0/25116.89.111.1 to 116.89.111.126116.89.111.127126
224116.89.111.128/25116.89.111.129 to 116.89.111.254116.89.111.255126
225116.89.112.0/25116.89.112.1 to 116.89.112.126116.89.112.127126
226116.89.112.128/25116.89.112.129 to 116.89.112.254116.89.112.255126
227116.89.113.0/25116.89.113.1 to 116.89.113.126116.89.113.127126
228116.89.113.128/25116.89.113.129 to 116.89.113.254116.89.113.255126
229116.89.114.0/25116.89.114.1 to 116.89.114.126116.89.114.127126
230116.89.114.128/25116.89.114.129 to 116.89.114.254116.89.114.255126
231116.89.115.0/25116.89.115.1 to 116.89.115.126116.89.115.127126
232116.89.115.128/25116.89.115.129 to 116.89.115.254116.89.115.255126
233116.89.116.0/25116.89.116.1 to 116.89.116.126116.89.116.127126
234116.89.116.128/25116.89.116.129 to 116.89.116.254116.89.116.255126
235116.89.117.0/25116.89.117.1 to 116.89.117.126116.89.117.127126
236116.89.117.128/25116.89.117.129 to 116.89.117.254116.89.117.255126
237116.89.118.0/25116.89.118.1 to 116.89.118.126116.89.118.127126
238116.89.118.128/25116.89.118.129 to 116.89.118.254116.89.118.255126
239116.89.119.0/25116.89.119.1 to 116.89.119.126116.89.119.127126
240116.89.119.128/25116.89.119.129 to 116.89.119.254116.89.119.255126
241116.89.120.0/25116.89.120.1 to 116.89.120.126116.89.120.127126
242116.89.120.128/25116.89.120.129 to 116.89.120.254116.89.120.255126
243116.89.121.0/25116.89.121.1 to 116.89.121.126116.89.121.127126
244116.89.121.128/25116.89.121.129 to 116.89.121.254116.89.121.255126
245116.89.122.0/25116.89.122.1 to 116.89.122.126116.89.122.127126
246116.89.122.128/25116.89.122.129 to 116.89.122.254116.89.122.255126
247116.89.123.0/25116.89.123.1 to 116.89.123.126116.89.123.127126
248116.89.123.128/25116.89.123.129 to 116.89.123.254116.89.123.255126
249116.89.124.0/25116.89.124.1 to 116.89.124.126116.89.124.127126
250116.89.124.128/25116.89.124.129 to 116.89.124.254116.89.124.255126
251116.89.125.0/25116.89.125.1 to 116.89.125.126116.89.125.127126
252116.89.125.128/25116.89.125.129 to 116.89.125.254116.89.125.255126
253116.89.126.0/25116.89.126.1 to 116.89.126.126116.89.126.127126
254116.89.126.128/25116.89.126.129 to 116.89.126.254116.89.126.255126
255116.89.127.0/25116.89.127.1 to 116.89.127.126116.89.127.127126
256116.89.127.128/25116.89.127.129 to 116.89.127.254116.89.127.255126

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.