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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.

Network120.167.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
120.167.0.0
Broadcast address
120.167.255.255
First usable
120.167.0.1
Last usable
120.167.255.254
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 78A70000 · Integer 2024210432 to 2024275967
Reverse DNS zone
167.120.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01111000.10100111..00000000.00000000120.167.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01111000.10100111..00000000.00000000120.167.0.0
Broadcast01111000.10100111..11111111.11111111120.167.255.255
Split into smaller subnets/26
/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)

120.167.0.0/16 makes 1,024 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1120.167.0.0/26120.167.0.1 to 120.167.0.62120.167.0.6362
2120.167.0.64/26120.167.0.65 to 120.167.0.126120.167.0.12762
3120.167.0.128/26120.167.0.129 to 120.167.0.190120.167.0.19162
4120.167.0.192/26120.167.0.193 to 120.167.0.254120.167.0.25562
5120.167.1.0/26120.167.1.1 to 120.167.1.62120.167.1.6362
6120.167.1.64/26120.167.1.65 to 120.167.1.126120.167.1.12762
7120.167.1.128/26120.167.1.129 to 120.167.1.190120.167.1.19162
8120.167.1.192/26120.167.1.193 to 120.167.1.254120.167.1.25562
9120.167.2.0/26120.167.2.1 to 120.167.2.62120.167.2.6362
10120.167.2.64/26120.167.2.65 to 120.167.2.126120.167.2.12762
11120.167.2.128/26120.167.2.129 to 120.167.2.190120.167.2.19162
12120.167.2.192/26120.167.2.193 to 120.167.2.254120.167.2.25562
13120.167.3.0/26120.167.3.1 to 120.167.3.62120.167.3.6362
14120.167.3.64/26120.167.3.65 to 120.167.3.126120.167.3.12762
15120.167.3.128/26120.167.3.129 to 120.167.3.190120.167.3.19162
16120.167.3.192/26120.167.3.193 to 120.167.3.254120.167.3.25562
17120.167.4.0/26120.167.4.1 to 120.167.4.62120.167.4.6362
18120.167.4.64/26120.167.4.65 to 120.167.4.126120.167.4.12762
19120.167.4.128/26120.167.4.129 to 120.167.4.190120.167.4.19162
20120.167.4.192/26120.167.4.193 to 120.167.4.254120.167.4.25562
21120.167.5.0/26120.167.5.1 to 120.167.5.62120.167.5.6362
22120.167.5.64/26120.167.5.65 to 120.167.5.126120.167.5.12762
23120.167.5.128/26120.167.5.129 to 120.167.5.190120.167.5.19162
24120.167.5.192/26120.167.5.193 to 120.167.5.254120.167.5.25562
25120.167.6.0/26120.167.6.1 to 120.167.6.62120.167.6.6362
26120.167.6.64/26120.167.6.65 to 120.167.6.126120.167.6.12762
27120.167.6.128/26120.167.6.129 to 120.167.6.190120.167.6.19162
28120.167.6.192/26120.167.6.193 to 120.167.6.254120.167.6.25562
29120.167.7.0/26120.167.7.1 to 120.167.7.62120.167.7.6362
30120.167.7.64/26120.167.7.65 to 120.167.7.126120.167.7.12762
31120.167.7.128/26120.167.7.129 to 120.167.7.190120.167.7.19162
32120.167.7.192/26120.167.7.193 to 120.167.7.254120.167.7.25562
33120.167.8.0/26120.167.8.1 to 120.167.8.62120.167.8.6362
34120.167.8.64/26120.167.8.65 to 120.167.8.126120.167.8.12762
35120.167.8.128/26120.167.8.129 to 120.167.8.190120.167.8.19162
36120.167.8.192/26120.167.8.193 to 120.167.8.254120.167.8.25562
37120.167.9.0/26120.167.9.1 to 120.167.9.62120.167.9.6362
38120.167.9.64/26120.167.9.65 to 120.167.9.126120.167.9.12762
39120.167.9.128/26120.167.9.129 to 120.167.9.190120.167.9.19162
40120.167.9.192/26120.167.9.193 to 120.167.9.254120.167.9.25562
41120.167.10.0/26120.167.10.1 to 120.167.10.62120.167.10.6362
42120.167.10.64/26120.167.10.65 to 120.167.10.126120.167.10.12762
43120.167.10.128/26120.167.10.129 to 120.167.10.190120.167.10.19162
44120.167.10.192/26120.167.10.193 to 120.167.10.254120.167.10.25562
45120.167.11.0/26120.167.11.1 to 120.167.11.62120.167.11.6362
46120.167.11.64/26120.167.11.65 to 120.167.11.126120.167.11.12762
47120.167.11.128/26120.167.11.129 to 120.167.11.190120.167.11.19162
48120.167.11.192/26120.167.11.193 to 120.167.11.254120.167.11.25562
49120.167.12.0/26120.167.12.1 to 120.167.12.62120.167.12.6362
50120.167.12.64/26120.167.12.65 to 120.167.12.126120.167.12.12762
51120.167.12.128/26120.167.12.129 to 120.167.12.190120.167.12.19162
52120.167.12.192/26120.167.12.193 to 120.167.12.254120.167.12.25562
53120.167.13.0/26120.167.13.1 to 120.167.13.62120.167.13.6362
54120.167.13.64/26120.167.13.65 to 120.167.13.126120.167.13.12762
55120.167.13.128/26120.167.13.129 to 120.167.13.190120.167.13.19162
56120.167.13.192/26120.167.13.193 to 120.167.13.254120.167.13.25562
57120.167.14.0/26120.167.14.1 to 120.167.14.62120.167.14.6362
58120.167.14.64/26120.167.14.65 to 120.167.14.126120.167.14.12762
59120.167.14.128/26120.167.14.129 to 120.167.14.190120.167.14.19162
60120.167.14.192/26120.167.14.193 to 120.167.14.254120.167.14.25562
61120.167.15.0/26120.167.15.1 to 120.167.15.62120.167.15.6362
62120.167.15.64/26120.167.15.65 to 120.167.15.126120.167.15.12762
63120.167.15.128/26120.167.15.129 to 120.167.15.190120.167.15.19162
64120.167.15.192/26120.167.15.193 to 120.167.15.254120.167.15.25562
65120.167.16.0/26120.167.16.1 to 120.167.16.62120.167.16.6362
66120.167.16.64/26120.167.16.65 to 120.167.16.126120.167.16.12762
67120.167.16.128/26120.167.16.129 to 120.167.16.190120.167.16.19162
68120.167.16.192/26120.167.16.193 to 120.167.16.254120.167.16.25562
69120.167.17.0/26120.167.17.1 to 120.167.17.62120.167.17.6362
70120.167.17.64/26120.167.17.65 to 120.167.17.126120.167.17.12762
71120.167.17.128/26120.167.17.129 to 120.167.17.190120.167.17.19162
72120.167.17.192/26120.167.17.193 to 120.167.17.254120.167.17.25562
73120.167.18.0/26120.167.18.1 to 120.167.18.62120.167.18.6362
74120.167.18.64/26120.167.18.65 to 120.167.18.126120.167.18.12762
75120.167.18.128/26120.167.18.129 to 120.167.18.190120.167.18.19162
76120.167.18.192/26120.167.18.193 to 120.167.18.254120.167.18.25562
77120.167.19.0/26120.167.19.1 to 120.167.19.62120.167.19.6362
78120.167.19.64/26120.167.19.65 to 120.167.19.126120.167.19.12762
79120.167.19.128/26120.167.19.129 to 120.167.19.190120.167.19.19162
80120.167.19.192/26120.167.19.193 to 120.167.19.254120.167.19.25562
81120.167.20.0/26120.167.20.1 to 120.167.20.62120.167.20.6362
82120.167.20.64/26120.167.20.65 to 120.167.20.126120.167.20.12762
83120.167.20.128/26120.167.20.129 to 120.167.20.190120.167.20.19162
84120.167.20.192/26120.167.20.193 to 120.167.20.254120.167.20.25562
85120.167.21.0/26120.167.21.1 to 120.167.21.62120.167.21.6362
86120.167.21.64/26120.167.21.65 to 120.167.21.126120.167.21.12762
87120.167.21.128/26120.167.21.129 to 120.167.21.190120.167.21.19162
88120.167.21.192/26120.167.21.193 to 120.167.21.254120.167.21.25562
89120.167.22.0/26120.167.22.1 to 120.167.22.62120.167.22.6362
90120.167.22.64/26120.167.22.65 to 120.167.22.126120.167.22.12762
91120.167.22.128/26120.167.22.129 to 120.167.22.190120.167.22.19162
92120.167.22.192/26120.167.22.193 to 120.167.22.254120.167.22.25562
93120.167.23.0/26120.167.23.1 to 120.167.23.62120.167.23.6362
94120.167.23.64/26120.167.23.65 to 120.167.23.126120.167.23.12762
95120.167.23.128/26120.167.23.129 to 120.167.23.190120.167.23.19162
96120.167.23.192/26120.167.23.193 to 120.167.23.254120.167.23.25562
97120.167.24.0/26120.167.24.1 to 120.167.24.62120.167.24.6362
98120.167.24.64/26120.167.24.65 to 120.167.24.126120.167.24.12762
99120.167.24.128/26120.167.24.129 to 120.167.24.190120.167.24.19162
100120.167.24.192/26120.167.24.193 to 120.167.24.254120.167.24.25562
101120.167.25.0/26120.167.25.1 to 120.167.25.62120.167.25.6362
102120.167.25.64/26120.167.25.65 to 120.167.25.126120.167.25.12762
103120.167.25.128/26120.167.25.129 to 120.167.25.190120.167.25.19162
104120.167.25.192/26120.167.25.193 to 120.167.25.254120.167.25.25562
105120.167.26.0/26120.167.26.1 to 120.167.26.62120.167.26.6362
106120.167.26.64/26120.167.26.65 to 120.167.26.126120.167.26.12762
107120.167.26.128/26120.167.26.129 to 120.167.26.190120.167.26.19162
108120.167.26.192/26120.167.26.193 to 120.167.26.254120.167.26.25562
109120.167.27.0/26120.167.27.1 to 120.167.27.62120.167.27.6362
110120.167.27.64/26120.167.27.65 to 120.167.27.126120.167.27.12762
111120.167.27.128/26120.167.27.129 to 120.167.27.190120.167.27.19162
112120.167.27.192/26120.167.27.193 to 120.167.27.254120.167.27.25562
113120.167.28.0/26120.167.28.1 to 120.167.28.62120.167.28.6362
114120.167.28.64/26120.167.28.65 to 120.167.28.126120.167.28.12762
115120.167.28.128/26120.167.28.129 to 120.167.28.190120.167.28.19162
116120.167.28.192/26120.167.28.193 to 120.167.28.254120.167.28.25562
117120.167.29.0/26120.167.29.1 to 120.167.29.62120.167.29.6362
118120.167.29.64/26120.167.29.65 to 120.167.29.126120.167.29.12762
119120.167.29.128/26120.167.29.129 to 120.167.29.190120.167.29.19162
120120.167.29.192/26120.167.29.193 to 120.167.29.254120.167.29.25562
121120.167.30.0/26120.167.30.1 to 120.167.30.62120.167.30.6362
122120.167.30.64/26120.167.30.65 to 120.167.30.126120.167.30.12762
123120.167.30.128/26120.167.30.129 to 120.167.30.190120.167.30.19162
124120.167.30.192/26120.167.30.193 to 120.167.30.254120.167.30.25562
125120.167.31.0/26120.167.31.1 to 120.167.31.62120.167.31.6362
126120.167.31.64/26120.167.31.65 to 120.167.31.126120.167.31.12762
127120.167.31.128/26120.167.31.129 to 120.167.31.190120.167.31.19162
128120.167.31.192/26120.167.31.193 to 120.167.31.254120.167.31.25562
129120.167.32.0/26120.167.32.1 to 120.167.32.62120.167.32.6362
130120.167.32.64/26120.167.32.65 to 120.167.32.126120.167.32.12762
131120.167.32.128/26120.167.32.129 to 120.167.32.190120.167.32.19162
132120.167.32.192/26120.167.32.193 to 120.167.32.254120.167.32.25562
133120.167.33.0/26120.167.33.1 to 120.167.33.62120.167.33.6362
134120.167.33.64/26120.167.33.65 to 120.167.33.126120.167.33.12762
135120.167.33.128/26120.167.33.129 to 120.167.33.190120.167.33.19162
136120.167.33.192/26120.167.33.193 to 120.167.33.254120.167.33.25562
137120.167.34.0/26120.167.34.1 to 120.167.34.62120.167.34.6362
138120.167.34.64/26120.167.34.65 to 120.167.34.126120.167.34.12762
139120.167.34.128/26120.167.34.129 to 120.167.34.190120.167.34.19162
140120.167.34.192/26120.167.34.193 to 120.167.34.254120.167.34.25562
141120.167.35.0/26120.167.35.1 to 120.167.35.62120.167.35.6362
142120.167.35.64/26120.167.35.65 to 120.167.35.126120.167.35.12762
143120.167.35.128/26120.167.35.129 to 120.167.35.190120.167.35.19162
144120.167.35.192/26120.167.35.193 to 120.167.35.254120.167.35.25562
145120.167.36.0/26120.167.36.1 to 120.167.36.62120.167.36.6362
146120.167.36.64/26120.167.36.65 to 120.167.36.126120.167.36.12762
147120.167.36.128/26120.167.36.129 to 120.167.36.190120.167.36.19162
148120.167.36.192/26120.167.36.193 to 120.167.36.254120.167.36.25562
149120.167.37.0/26120.167.37.1 to 120.167.37.62120.167.37.6362
150120.167.37.64/26120.167.37.65 to 120.167.37.126120.167.37.12762
151120.167.37.128/26120.167.37.129 to 120.167.37.190120.167.37.19162
152120.167.37.192/26120.167.37.193 to 120.167.37.254120.167.37.25562
153120.167.38.0/26120.167.38.1 to 120.167.38.62120.167.38.6362
154120.167.38.64/26120.167.38.65 to 120.167.38.126120.167.38.12762
155120.167.38.128/26120.167.38.129 to 120.167.38.190120.167.38.19162
156120.167.38.192/26120.167.38.193 to 120.167.38.254120.167.38.25562
157120.167.39.0/26120.167.39.1 to 120.167.39.62120.167.39.6362
158120.167.39.64/26120.167.39.65 to 120.167.39.126120.167.39.12762
159120.167.39.128/26120.167.39.129 to 120.167.39.190120.167.39.19162
160120.167.39.192/26120.167.39.193 to 120.167.39.254120.167.39.25562
161120.167.40.0/26120.167.40.1 to 120.167.40.62120.167.40.6362
162120.167.40.64/26120.167.40.65 to 120.167.40.126120.167.40.12762
163120.167.40.128/26120.167.40.129 to 120.167.40.190120.167.40.19162
164120.167.40.192/26120.167.40.193 to 120.167.40.254120.167.40.25562
165120.167.41.0/26120.167.41.1 to 120.167.41.62120.167.41.6362
166120.167.41.64/26120.167.41.65 to 120.167.41.126120.167.41.12762
167120.167.41.128/26120.167.41.129 to 120.167.41.190120.167.41.19162
168120.167.41.192/26120.167.41.193 to 120.167.41.254120.167.41.25562
169120.167.42.0/26120.167.42.1 to 120.167.42.62120.167.42.6362
170120.167.42.64/26120.167.42.65 to 120.167.42.126120.167.42.12762
171120.167.42.128/26120.167.42.129 to 120.167.42.190120.167.42.19162
172120.167.42.192/26120.167.42.193 to 120.167.42.254120.167.42.25562
173120.167.43.0/26120.167.43.1 to 120.167.43.62120.167.43.6362
174120.167.43.64/26120.167.43.65 to 120.167.43.126120.167.43.12762
175120.167.43.128/26120.167.43.129 to 120.167.43.190120.167.43.19162
176120.167.43.192/26120.167.43.193 to 120.167.43.254120.167.43.25562
177120.167.44.0/26120.167.44.1 to 120.167.44.62120.167.44.6362
178120.167.44.64/26120.167.44.65 to 120.167.44.126120.167.44.12762
179120.167.44.128/26120.167.44.129 to 120.167.44.190120.167.44.19162
180120.167.44.192/26120.167.44.193 to 120.167.44.254120.167.44.25562
181120.167.45.0/26120.167.45.1 to 120.167.45.62120.167.45.6362
182120.167.45.64/26120.167.45.65 to 120.167.45.126120.167.45.12762
183120.167.45.128/26120.167.45.129 to 120.167.45.190120.167.45.19162
184120.167.45.192/26120.167.45.193 to 120.167.45.254120.167.45.25562
185120.167.46.0/26120.167.46.1 to 120.167.46.62120.167.46.6362
186120.167.46.64/26120.167.46.65 to 120.167.46.126120.167.46.12762
187120.167.46.128/26120.167.46.129 to 120.167.46.190120.167.46.19162
188120.167.46.192/26120.167.46.193 to 120.167.46.254120.167.46.25562
189120.167.47.0/26120.167.47.1 to 120.167.47.62120.167.47.6362
190120.167.47.64/26120.167.47.65 to 120.167.47.126120.167.47.12762
191120.167.47.128/26120.167.47.129 to 120.167.47.190120.167.47.19162
192120.167.47.192/26120.167.47.193 to 120.167.47.254120.167.47.25562
193120.167.48.0/26120.167.48.1 to 120.167.48.62120.167.48.6362
194120.167.48.64/26120.167.48.65 to 120.167.48.126120.167.48.12762
195120.167.48.128/26120.167.48.129 to 120.167.48.190120.167.48.19162
196120.167.48.192/26120.167.48.193 to 120.167.48.254120.167.48.25562
197120.167.49.0/26120.167.49.1 to 120.167.49.62120.167.49.6362
198120.167.49.64/26120.167.49.65 to 120.167.49.126120.167.49.12762
199120.167.49.128/26120.167.49.129 to 120.167.49.190120.167.49.19162
200120.167.49.192/26120.167.49.193 to 120.167.49.254120.167.49.25562
201120.167.50.0/26120.167.50.1 to 120.167.50.62120.167.50.6362
202120.167.50.64/26120.167.50.65 to 120.167.50.126120.167.50.12762
203120.167.50.128/26120.167.50.129 to 120.167.50.190120.167.50.19162
204120.167.50.192/26120.167.50.193 to 120.167.50.254120.167.50.25562
205120.167.51.0/26120.167.51.1 to 120.167.51.62120.167.51.6362
206120.167.51.64/26120.167.51.65 to 120.167.51.126120.167.51.12762
207120.167.51.128/26120.167.51.129 to 120.167.51.190120.167.51.19162
208120.167.51.192/26120.167.51.193 to 120.167.51.254120.167.51.25562
209120.167.52.0/26120.167.52.1 to 120.167.52.62120.167.52.6362
210120.167.52.64/26120.167.52.65 to 120.167.52.126120.167.52.12762
211120.167.52.128/26120.167.52.129 to 120.167.52.190120.167.52.19162
212120.167.52.192/26120.167.52.193 to 120.167.52.254120.167.52.25562
213120.167.53.0/26120.167.53.1 to 120.167.53.62120.167.53.6362
214120.167.53.64/26120.167.53.65 to 120.167.53.126120.167.53.12762
215120.167.53.128/26120.167.53.129 to 120.167.53.190120.167.53.19162
216120.167.53.192/26120.167.53.193 to 120.167.53.254120.167.53.25562
217120.167.54.0/26120.167.54.1 to 120.167.54.62120.167.54.6362
218120.167.54.64/26120.167.54.65 to 120.167.54.126120.167.54.12762
219120.167.54.128/26120.167.54.129 to 120.167.54.190120.167.54.19162
220120.167.54.192/26120.167.54.193 to 120.167.54.254120.167.54.25562
221120.167.55.0/26120.167.55.1 to 120.167.55.62120.167.55.6362
222120.167.55.64/26120.167.55.65 to 120.167.55.126120.167.55.12762
223120.167.55.128/26120.167.55.129 to 120.167.55.190120.167.55.19162
224120.167.55.192/26120.167.55.193 to 120.167.55.254120.167.55.25562
225120.167.56.0/26120.167.56.1 to 120.167.56.62120.167.56.6362
226120.167.56.64/26120.167.56.65 to 120.167.56.126120.167.56.12762
227120.167.56.128/26120.167.56.129 to 120.167.56.190120.167.56.19162
228120.167.56.192/26120.167.56.193 to 120.167.56.254120.167.56.25562
229120.167.57.0/26120.167.57.1 to 120.167.57.62120.167.57.6362
230120.167.57.64/26120.167.57.65 to 120.167.57.126120.167.57.12762
231120.167.57.128/26120.167.57.129 to 120.167.57.190120.167.57.19162
232120.167.57.192/26120.167.57.193 to 120.167.57.254120.167.57.25562
233120.167.58.0/26120.167.58.1 to 120.167.58.62120.167.58.6362
234120.167.58.64/26120.167.58.65 to 120.167.58.126120.167.58.12762
235120.167.58.128/26120.167.58.129 to 120.167.58.190120.167.58.19162
236120.167.58.192/26120.167.58.193 to 120.167.58.254120.167.58.25562
237120.167.59.0/26120.167.59.1 to 120.167.59.62120.167.59.6362
238120.167.59.64/26120.167.59.65 to 120.167.59.126120.167.59.12762
239120.167.59.128/26120.167.59.129 to 120.167.59.190120.167.59.19162
240120.167.59.192/26120.167.59.193 to 120.167.59.254120.167.59.25562
241120.167.60.0/26120.167.60.1 to 120.167.60.62120.167.60.6362
242120.167.60.64/26120.167.60.65 to 120.167.60.126120.167.60.12762
243120.167.60.128/26120.167.60.129 to 120.167.60.190120.167.60.19162
244120.167.60.192/26120.167.60.193 to 120.167.60.254120.167.60.25562
245120.167.61.0/26120.167.61.1 to 120.167.61.62120.167.61.6362
246120.167.61.64/26120.167.61.65 to 120.167.61.126120.167.61.12762
247120.167.61.128/26120.167.61.129 to 120.167.61.190120.167.61.19162
248120.167.61.192/26120.167.61.193 to 120.167.61.254120.167.61.25562
249120.167.62.0/26120.167.62.1 to 120.167.62.62120.167.62.6362
250120.167.62.64/26120.167.62.65 to 120.167.62.126120.167.62.12762
251120.167.62.128/26120.167.62.129 to 120.167.62.190120.167.62.19162
252120.167.62.192/26120.167.62.193 to 120.167.62.254120.167.62.25562
253120.167.63.0/26120.167.63.1 to 120.167.63.62120.167.63.6362
254120.167.63.64/26120.167.63.65 to 120.167.63.126120.167.63.12762
255120.167.63.128/26120.167.63.129 to 120.167.63.190120.167.63.19162
256120.167.63.192/26120.167.63.193 to 120.167.63.254120.167.63.25562

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.