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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.

Network175.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
175.232.0.0
Broadcast address
175.235.255.255
First usable
175.232.0.1
Last usable
175.235.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
B (default /16)
As numbers
Hex AFE80000 · Integer 2951217152 to 2951479295
Reverse DNS zones
232.175.in-addr.arpa
233.175.in-addr.arpa
234.175.in-addr.arpa
235.175.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10101111.11101000.00000000.00000000175.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10101111.11101000.00000000.00000000175.232.0.0
Broadcast10101111.11101011.11111111.11111111175.235.255.255
Split into smaller subnets/26
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

175.232.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1175.232.0.0/26175.232.0.1 to 175.232.0.62175.232.0.6362
2175.232.0.64/26175.232.0.65 to 175.232.0.126175.232.0.12762
3175.232.0.128/26175.232.0.129 to 175.232.0.190175.232.0.19162
4175.232.0.192/26175.232.0.193 to 175.232.0.254175.232.0.25562
5175.232.1.0/26175.232.1.1 to 175.232.1.62175.232.1.6362
6175.232.1.64/26175.232.1.65 to 175.232.1.126175.232.1.12762
7175.232.1.128/26175.232.1.129 to 175.232.1.190175.232.1.19162
8175.232.1.192/26175.232.1.193 to 175.232.1.254175.232.1.25562
9175.232.2.0/26175.232.2.1 to 175.232.2.62175.232.2.6362
10175.232.2.64/26175.232.2.65 to 175.232.2.126175.232.2.12762
11175.232.2.128/26175.232.2.129 to 175.232.2.190175.232.2.19162
12175.232.2.192/26175.232.2.193 to 175.232.2.254175.232.2.25562
13175.232.3.0/26175.232.3.1 to 175.232.3.62175.232.3.6362
14175.232.3.64/26175.232.3.65 to 175.232.3.126175.232.3.12762
15175.232.3.128/26175.232.3.129 to 175.232.3.190175.232.3.19162
16175.232.3.192/26175.232.3.193 to 175.232.3.254175.232.3.25562
17175.232.4.0/26175.232.4.1 to 175.232.4.62175.232.4.6362
18175.232.4.64/26175.232.4.65 to 175.232.4.126175.232.4.12762
19175.232.4.128/26175.232.4.129 to 175.232.4.190175.232.4.19162
20175.232.4.192/26175.232.4.193 to 175.232.4.254175.232.4.25562
21175.232.5.0/26175.232.5.1 to 175.232.5.62175.232.5.6362
22175.232.5.64/26175.232.5.65 to 175.232.5.126175.232.5.12762
23175.232.5.128/26175.232.5.129 to 175.232.5.190175.232.5.19162
24175.232.5.192/26175.232.5.193 to 175.232.5.254175.232.5.25562
25175.232.6.0/26175.232.6.1 to 175.232.6.62175.232.6.6362
26175.232.6.64/26175.232.6.65 to 175.232.6.126175.232.6.12762
27175.232.6.128/26175.232.6.129 to 175.232.6.190175.232.6.19162
28175.232.6.192/26175.232.6.193 to 175.232.6.254175.232.6.25562
29175.232.7.0/26175.232.7.1 to 175.232.7.62175.232.7.6362
30175.232.7.64/26175.232.7.65 to 175.232.7.126175.232.7.12762
31175.232.7.128/26175.232.7.129 to 175.232.7.190175.232.7.19162
32175.232.7.192/26175.232.7.193 to 175.232.7.254175.232.7.25562
33175.232.8.0/26175.232.8.1 to 175.232.8.62175.232.8.6362
34175.232.8.64/26175.232.8.65 to 175.232.8.126175.232.8.12762
35175.232.8.128/26175.232.8.129 to 175.232.8.190175.232.8.19162
36175.232.8.192/26175.232.8.193 to 175.232.8.254175.232.8.25562
37175.232.9.0/26175.232.9.1 to 175.232.9.62175.232.9.6362
38175.232.9.64/26175.232.9.65 to 175.232.9.126175.232.9.12762
39175.232.9.128/26175.232.9.129 to 175.232.9.190175.232.9.19162
40175.232.9.192/26175.232.9.193 to 175.232.9.254175.232.9.25562
41175.232.10.0/26175.232.10.1 to 175.232.10.62175.232.10.6362
42175.232.10.64/26175.232.10.65 to 175.232.10.126175.232.10.12762
43175.232.10.128/26175.232.10.129 to 175.232.10.190175.232.10.19162
44175.232.10.192/26175.232.10.193 to 175.232.10.254175.232.10.25562
45175.232.11.0/26175.232.11.1 to 175.232.11.62175.232.11.6362
46175.232.11.64/26175.232.11.65 to 175.232.11.126175.232.11.12762
47175.232.11.128/26175.232.11.129 to 175.232.11.190175.232.11.19162
48175.232.11.192/26175.232.11.193 to 175.232.11.254175.232.11.25562
49175.232.12.0/26175.232.12.1 to 175.232.12.62175.232.12.6362
50175.232.12.64/26175.232.12.65 to 175.232.12.126175.232.12.12762
51175.232.12.128/26175.232.12.129 to 175.232.12.190175.232.12.19162
52175.232.12.192/26175.232.12.193 to 175.232.12.254175.232.12.25562
53175.232.13.0/26175.232.13.1 to 175.232.13.62175.232.13.6362
54175.232.13.64/26175.232.13.65 to 175.232.13.126175.232.13.12762
55175.232.13.128/26175.232.13.129 to 175.232.13.190175.232.13.19162
56175.232.13.192/26175.232.13.193 to 175.232.13.254175.232.13.25562
57175.232.14.0/26175.232.14.1 to 175.232.14.62175.232.14.6362
58175.232.14.64/26175.232.14.65 to 175.232.14.126175.232.14.12762
59175.232.14.128/26175.232.14.129 to 175.232.14.190175.232.14.19162
60175.232.14.192/26175.232.14.193 to 175.232.14.254175.232.14.25562
61175.232.15.0/26175.232.15.1 to 175.232.15.62175.232.15.6362
62175.232.15.64/26175.232.15.65 to 175.232.15.126175.232.15.12762
63175.232.15.128/26175.232.15.129 to 175.232.15.190175.232.15.19162
64175.232.15.192/26175.232.15.193 to 175.232.15.254175.232.15.25562
65175.232.16.0/26175.232.16.1 to 175.232.16.62175.232.16.6362
66175.232.16.64/26175.232.16.65 to 175.232.16.126175.232.16.12762
67175.232.16.128/26175.232.16.129 to 175.232.16.190175.232.16.19162
68175.232.16.192/26175.232.16.193 to 175.232.16.254175.232.16.25562
69175.232.17.0/26175.232.17.1 to 175.232.17.62175.232.17.6362
70175.232.17.64/26175.232.17.65 to 175.232.17.126175.232.17.12762
71175.232.17.128/26175.232.17.129 to 175.232.17.190175.232.17.19162
72175.232.17.192/26175.232.17.193 to 175.232.17.254175.232.17.25562
73175.232.18.0/26175.232.18.1 to 175.232.18.62175.232.18.6362
74175.232.18.64/26175.232.18.65 to 175.232.18.126175.232.18.12762
75175.232.18.128/26175.232.18.129 to 175.232.18.190175.232.18.19162
76175.232.18.192/26175.232.18.193 to 175.232.18.254175.232.18.25562
77175.232.19.0/26175.232.19.1 to 175.232.19.62175.232.19.6362
78175.232.19.64/26175.232.19.65 to 175.232.19.126175.232.19.12762
79175.232.19.128/26175.232.19.129 to 175.232.19.190175.232.19.19162
80175.232.19.192/26175.232.19.193 to 175.232.19.254175.232.19.25562
81175.232.20.0/26175.232.20.1 to 175.232.20.62175.232.20.6362
82175.232.20.64/26175.232.20.65 to 175.232.20.126175.232.20.12762
83175.232.20.128/26175.232.20.129 to 175.232.20.190175.232.20.19162
84175.232.20.192/26175.232.20.193 to 175.232.20.254175.232.20.25562
85175.232.21.0/26175.232.21.1 to 175.232.21.62175.232.21.6362
86175.232.21.64/26175.232.21.65 to 175.232.21.126175.232.21.12762
87175.232.21.128/26175.232.21.129 to 175.232.21.190175.232.21.19162
88175.232.21.192/26175.232.21.193 to 175.232.21.254175.232.21.25562
89175.232.22.0/26175.232.22.1 to 175.232.22.62175.232.22.6362
90175.232.22.64/26175.232.22.65 to 175.232.22.126175.232.22.12762
91175.232.22.128/26175.232.22.129 to 175.232.22.190175.232.22.19162
92175.232.22.192/26175.232.22.193 to 175.232.22.254175.232.22.25562
93175.232.23.0/26175.232.23.1 to 175.232.23.62175.232.23.6362
94175.232.23.64/26175.232.23.65 to 175.232.23.126175.232.23.12762
95175.232.23.128/26175.232.23.129 to 175.232.23.190175.232.23.19162
96175.232.23.192/26175.232.23.193 to 175.232.23.254175.232.23.25562
97175.232.24.0/26175.232.24.1 to 175.232.24.62175.232.24.6362
98175.232.24.64/26175.232.24.65 to 175.232.24.126175.232.24.12762
99175.232.24.128/26175.232.24.129 to 175.232.24.190175.232.24.19162
100175.232.24.192/26175.232.24.193 to 175.232.24.254175.232.24.25562
101175.232.25.0/26175.232.25.1 to 175.232.25.62175.232.25.6362
102175.232.25.64/26175.232.25.65 to 175.232.25.126175.232.25.12762
103175.232.25.128/26175.232.25.129 to 175.232.25.190175.232.25.19162
104175.232.25.192/26175.232.25.193 to 175.232.25.254175.232.25.25562
105175.232.26.0/26175.232.26.1 to 175.232.26.62175.232.26.6362
106175.232.26.64/26175.232.26.65 to 175.232.26.126175.232.26.12762
107175.232.26.128/26175.232.26.129 to 175.232.26.190175.232.26.19162
108175.232.26.192/26175.232.26.193 to 175.232.26.254175.232.26.25562
109175.232.27.0/26175.232.27.1 to 175.232.27.62175.232.27.6362
110175.232.27.64/26175.232.27.65 to 175.232.27.126175.232.27.12762
111175.232.27.128/26175.232.27.129 to 175.232.27.190175.232.27.19162
112175.232.27.192/26175.232.27.193 to 175.232.27.254175.232.27.25562
113175.232.28.0/26175.232.28.1 to 175.232.28.62175.232.28.6362
114175.232.28.64/26175.232.28.65 to 175.232.28.126175.232.28.12762
115175.232.28.128/26175.232.28.129 to 175.232.28.190175.232.28.19162
116175.232.28.192/26175.232.28.193 to 175.232.28.254175.232.28.25562
117175.232.29.0/26175.232.29.1 to 175.232.29.62175.232.29.6362
118175.232.29.64/26175.232.29.65 to 175.232.29.126175.232.29.12762
119175.232.29.128/26175.232.29.129 to 175.232.29.190175.232.29.19162
120175.232.29.192/26175.232.29.193 to 175.232.29.254175.232.29.25562
121175.232.30.0/26175.232.30.1 to 175.232.30.62175.232.30.6362
122175.232.30.64/26175.232.30.65 to 175.232.30.126175.232.30.12762
123175.232.30.128/26175.232.30.129 to 175.232.30.190175.232.30.19162
124175.232.30.192/26175.232.30.193 to 175.232.30.254175.232.30.25562
125175.232.31.0/26175.232.31.1 to 175.232.31.62175.232.31.6362
126175.232.31.64/26175.232.31.65 to 175.232.31.126175.232.31.12762
127175.232.31.128/26175.232.31.129 to 175.232.31.190175.232.31.19162
128175.232.31.192/26175.232.31.193 to 175.232.31.254175.232.31.25562
129175.232.32.0/26175.232.32.1 to 175.232.32.62175.232.32.6362
130175.232.32.64/26175.232.32.65 to 175.232.32.126175.232.32.12762
131175.232.32.128/26175.232.32.129 to 175.232.32.190175.232.32.19162
132175.232.32.192/26175.232.32.193 to 175.232.32.254175.232.32.25562
133175.232.33.0/26175.232.33.1 to 175.232.33.62175.232.33.6362
134175.232.33.64/26175.232.33.65 to 175.232.33.126175.232.33.12762
135175.232.33.128/26175.232.33.129 to 175.232.33.190175.232.33.19162
136175.232.33.192/26175.232.33.193 to 175.232.33.254175.232.33.25562
137175.232.34.0/26175.232.34.1 to 175.232.34.62175.232.34.6362
138175.232.34.64/26175.232.34.65 to 175.232.34.126175.232.34.12762
139175.232.34.128/26175.232.34.129 to 175.232.34.190175.232.34.19162
140175.232.34.192/26175.232.34.193 to 175.232.34.254175.232.34.25562
141175.232.35.0/26175.232.35.1 to 175.232.35.62175.232.35.6362
142175.232.35.64/26175.232.35.65 to 175.232.35.126175.232.35.12762
143175.232.35.128/26175.232.35.129 to 175.232.35.190175.232.35.19162
144175.232.35.192/26175.232.35.193 to 175.232.35.254175.232.35.25562
145175.232.36.0/26175.232.36.1 to 175.232.36.62175.232.36.6362
146175.232.36.64/26175.232.36.65 to 175.232.36.126175.232.36.12762
147175.232.36.128/26175.232.36.129 to 175.232.36.190175.232.36.19162
148175.232.36.192/26175.232.36.193 to 175.232.36.254175.232.36.25562
149175.232.37.0/26175.232.37.1 to 175.232.37.62175.232.37.6362
150175.232.37.64/26175.232.37.65 to 175.232.37.126175.232.37.12762
151175.232.37.128/26175.232.37.129 to 175.232.37.190175.232.37.19162
152175.232.37.192/26175.232.37.193 to 175.232.37.254175.232.37.25562
153175.232.38.0/26175.232.38.1 to 175.232.38.62175.232.38.6362
154175.232.38.64/26175.232.38.65 to 175.232.38.126175.232.38.12762
155175.232.38.128/26175.232.38.129 to 175.232.38.190175.232.38.19162
156175.232.38.192/26175.232.38.193 to 175.232.38.254175.232.38.25562
157175.232.39.0/26175.232.39.1 to 175.232.39.62175.232.39.6362
158175.232.39.64/26175.232.39.65 to 175.232.39.126175.232.39.12762
159175.232.39.128/26175.232.39.129 to 175.232.39.190175.232.39.19162
160175.232.39.192/26175.232.39.193 to 175.232.39.254175.232.39.25562
161175.232.40.0/26175.232.40.1 to 175.232.40.62175.232.40.6362
162175.232.40.64/26175.232.40.65 to 175.232.40.126175.232.40.12762
163175.232.40.128/26175.232.40.129 to 175.232.40.190175.232.40.19162
164175.232.40.192/26175.232.40.193 to 175.232.40.254175.232.40.25562
165175.232.41.0/26175.232.41.1 to 175.232.41.62175.232.41.6362
166175.232.41.64/26175.232.41.65 to 175.232.41.126175.232.41.12762
167175.232.41.128/26175.232.41.129 to 175.232.41.190175.232.41.19162
168175.232.41.192/26175.232.41.193 to 175.232.41.254175.232.41.25562
169175.232.42.0/26175.232.42.1 to 175.232.42.62175.232.42.6362
170175.232.42.64/26175.232.42.65 to 175.232.42.126175.232.42.12762
171175.232.42.128/26175.232.42.129 to 175.232.42.190175.232.42.19162
172175.232.42.192/26175.232.42.193 to 175.232.42.254175.232.42.25562
173175.232.43.0/26175.232.43.1 to 175.232.43.62175.232.43.6362
174175.232.43.64/26175.232.43.65 to 175.232.43.126175.232.43.12762
175175.232.43.128/26175.232.43.129 to 175.232.43.190175.232.43.19162
176175.232.43.192/26175.232.43.193 to 175.232.43.254175.232.43.25562
177175.232.44.0/26175.232.44.1 to 175.232.44.62175.232.44.6362
178175.232.44.64/26175.232.44.65 to 175.232.44.126175.232.44.12762
179175.232.44.128/26175.232.44.129 to 175.232.44.190175.232.44.19162
180175.232.44.192/26175.232.44.193 to 175.232.44.254175.232.44.25562
181175.232.45.0/26175.232.45.1 to 175.232.45.62175.232.45.6362
182175.232.45.64/26175.232.45.65 to 175.232.45.126175.232.45.12762
183175.232.45.128/26175.232.45.129 to 175.232.45.190175.232.45.19162
184175.232.45.192/26175.232.45.193 to 175.232.45.254175.232.45.25562
185175.232.46.0/26175.232.46.1 to 175.232.46.62175.232.46.6362
186175.232.46.64/26175.232.46.65 to 175.232.46.126175.232.46.12762
187175.232.46.128/26175.232.46.129 to 175.232.46.190175.232.46.19162
188175.232.46.192/26175.232.46.193 to 175.232.46.254175.232.46.25562
189175.232.47.0/26175.232.47.1 to 175.232.47.62175.232.47.6362
190175.232.47.64/26175.232.47.65 to 175.232.47.126175.232.47.12762
191175.232.47.128/26175.232.47.129 to 175.232.47.190175.232.47.19162
192175.232.47.192/26175.232.47.193 to 175.232.47.254175.232.47.25562
193175.232.48.0/26175.232.48.1 to 175.232.48.62175.232.48.6362
194175.232.48.64/26175.232.48.65 to 175.232.48.126175.232.48.12762
195175.232.48.128/26175.232.48.129 to 175.232.48.190175.232.48.19162
196175.232.48.192/26175.232.48.193 to 175.232.48.254175.232.48.25562
197175.232.49.0/26175.232.49.1 to 175.232.49.62175.232.49.6362
198175.232.49.64/26175.232.49.65 to 175.232.49.126175.232.49.12762
199175.232.49.128/26175.232.49.129 to 175.232.49.190175.232.49.19162
200175.232.49.192/26175.232.49.193 to 175.232.49.254175.232.49.25562
201175.232.50.0/26175.232.50.1 to 175.232.50.62175.232.50.6362
202175.232.50.64/26175.232.50.65 to 175.232.50.126175.232.50.12762
203175.232.50.128/26175.232.50.129 to 175.232.50.190175.232.50.19162
204175.232.50.192/26175.232.50.193 to 175.232.50.254175.232.50.25562
205175.232.51.0/26175.232.51.1 to 175.232.51.62175.232.51.6362
206175.232.51.64/26175.232.51.65 to 175.232.51.126175.232.51.12762
207175.232.51.128/26175.232.51.129 to 175.232.51.190175.232.51.19162
208175.232.51.192/26175.232.51.193 to 175.232.51.254175.232.51.25562
209175.232.52.0/26175.232.52.1 to 175.232.52.62175.232.52.6362
210175.232.52.64/26175.232.52.65 to 175.232.52.126175.232.52.12762
211175.232.52.128/26175.232.52.129 to 175.232.52.190175.232.52.19162
212175.232.52.192/26175.232.52.193 to 175.232.52.254175.232.52.25562
213175.232.53.0/26175.232.53.1 to 175.232.53.62175.232.53.6362
214175.232.53.64/26175.232.53.65 to 175.232.53.126175.232.53.12762
215175.232.53.128/26175.232.53.129 to 175.232.53.190175.232.53.19162
216175.232.53.192/26175.232.53.193 to 175.232.53.254175.232.53.25562
217175.232.54.0/26175.232.54.1 to 175.232.54.62175.232.54.6362
218175.232.54.64/26175.232.54.65 to 175.232.54.126175.232.54.12762
219175.232.54.128/26175.232.54.129 to 175.232.54.190175.232.54.19162
220175.232.54.192/26175.232.54.193 to 175.232.54.254175.232.54.25562
221175.232.55.0/26175.232.55.1 to 175.232.55.62175.232.55.6362
222175.232.55.64/26175.232.55.65 to 175.232.55.126175.232.55.12762
223175.232.55.128/26175.232.55.129 to 175.232.55.190175.232.55.19162
224175.232.55.192/26175.232.55.193 to 175.232.55.254175.232.55.25562
225175.232.56.0/26175.232.56.1 to 175.232.56.62175.232.56.6362
226175.232.56.64/26175.232.56.65 to 175.232.56.126175.232.56.12762
227175.232.56.128/26175.232.56.129 to 175.232.56.190175.232.56.19162
228175.232.56.192/26175.232.56.193 to 175.232.56.254175.232.56.25562
229175.232.57.0/26175.232.57.1 to 175.232.57.62175.232.57.6362
230175.232.57.64/26175.232.57.65 to 175.232.57.126175.232.57.12762
231175.232.57.128/26175.232.57.129 to 175.232.57.190175.232.57.19162
232175.232.57.192/26175.232.57.193 to 175.232.57.254175.232.57.25562
233175.232.58.0/26175.232.58.1 to 175.232.58.62175.232.58.6362
234175.232.58.64/26175.232.58.65 to 175.232.58.126175.232.58.12762
235175.232.58.128/26175.232.58.129 to 175.232.58.190175.232.58.19162
236175.232.58.192/26175.232.58.193 to 175.232.58.254175.232.58.25562
237175.232.59.0/26175.232.59.1 to 175.232.59.62175.232.59.6362
238175.232.59.64/26175.232.59.65 to 175.232.59.126175.232.59.12762
239175.232.59.128/26175.232.59.129 to 175.232.59.190175.232.59.19162
240175.232.59.192/26175.232.59.193 to 175.232.59.254175.232.59.25562
241175.232.60.0/26175.232.60.1 to 175.232.60.62175.232.60.6362
242175.232.60.64/26175.232.60.65 to 175.232.60.126175.232.60.12762
243175.232.60.128/26175.232.60.129 to 175.232.60.190175.232.60.19162
244175.232.60.192/26175.232.60.193 to 175.232.60.254175.232.60.25562
245175.232.61.0/26175.232.61.1 to 175.232.61.62175.232.61.6362
246175.232.61.64/26175.232.61.65 to 175.232.61.126175.232.61.12762
247175.232.61.128/26175.232.61.129 to 175.232.61.190175.232.61.19162
248175.232.61.192/26175.232.61.193 to 175.232.61.254175.232.61.25562
249175.232.62.0/26175.232.62.1 to 175.232.62.62175.232.62.6362
250175.232.62.64/26175.232.62.65 to 175.232.62.126175.232.62.12762
251175.232.62.128/26175.232.62.129 to 175.232.62.190175.232.62.19162
252175.232.62.192/26175.232.62.193 to 175.232.62.254175.232.62.25562
253175.232.63.0/26175.232.63.1 to 175.232.63.62175.232.63.6362
254175.232.63.64/26175.232.63.65 to 175.232.63.126175.232.63.12762
255175.232.63.128/26175.232.63.129 to 175.232.63.190175.232.63.19162
256175.232.63.192/26175.232.63.193 to 175.232.63.254175.232.63.25562

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.