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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.

Network130.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
130.232.0.0
Broadcast address
130.235.255.255
First usable
130.232.0.1
Last usable
130.235.255.254
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 82E80000 · Integer 2196242432 to 2196504575
Reverse DNS zones
232.130.in-addr.arpa
233.130.in-addr.arpa
234.130.in-addr.arpa
235.130.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
Address10000010.11101000.00000000.00000000130.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10000010.11101000.00000000.00000000130.232.0.0
Broadcast10000010.11101011.11111111.11111111130.235.255.255
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)

130.232.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1130.232.0.0/26130.232.0.1 to 130.232.0.62130.232.0.6362
2130.232.0.64/26130.232.0.65 to 130.232.0.126130.232.0.12762
3130.232.0.128/26130.232.0.129 to 130.232.0.190130.232.0.19162
4130.232.0.192/26130.232.0.193 to 130.232.0.254130.232.0.25562
5130.232.1.0/26130.232.1.1 to 130.232.1.62130.232.1.6362
6130.232.1.64/26130.232.1.65 to 130.232.1.126130.232.1.12762
7130.232.1.128/26130.232.1.129 to 130.232.1.190130.232.1.19162
8130.232.1.192/26130.232.1.193 to 130.232.1.254130.232.1.25562
9130.232.2.0/26130.232.2.1 to 130.232.2.62130.232.2.6362
10130.232.2.64/26130.232.2.65 to 130.232.2.126130.232.2.12762
11130.232.2.128/26130.232.2.129 to 130.232.2.190130.232.2.19162
12130.232.2.192/26130.232.2.193 to 130.232.2.254130.232.2.25562
13130.232.3.0/26130.232.3.1 to 130.232.3.62130.232.3.6362
14130.232.3.64/26130.232.3.65 to 130.232.3.126130.232.3.12762
15130.232.3.128/26130.232.3.129 to 130.232.3.190130.232.3.19162
16130.232.3.192/26130.232.3.193 to 130.232.3.254130.232.3.25562
17130.232.4.0/26130.232.4.1 to 130.232.4.62130.232.4.6362
18130.232.4.64/26130.232.4.65 to 130.232.4.126130.232.4.12762
19130.232.4.128/26130.232.4.129 to 130.232.4.190130.232.4.19162
20130.232.4.192/26130.232.4.193 to 130.232.4.254130.232.4.25562
21130.232.5.0/26130.232.5.1 to 130.232.5.62130.232.5.6362
22130.232.5.64/26130.232.5.65 to 130.232.5.126130.232.5.12762
23130.232.5.128/26130.232.5.129 to 130.232.5.190130.232.5.19162
24130.232.5.192/26130.232.5.193 to 130.232.5.254130.232.5.25562
25130.232.6.0/26130.232.6.1 to 130.232.6.62130.232.6.6362
26130.232.6.64/26130.232.6.65 to 130.232.6.126130.232.6.12762
27130.232.6.128/26130.232.6.129 to 130.232.6.190130.232.6.19162
28130.232.6.192/26130.232.6.193 to 130.232.6.254130.232.6.25562
29130.232.7.0/26130.232.7.1 to 130.232.7.62130.232.7.6362
30130.232.7.64/26130.232.7.65 to 130.232.7.126130.232.7.12762
31130.232.7.128/26130.232.7.129 to 130.232.7.190130.232.7.19162
32130.232.7.192/26130.232.7.193 to 130.232.7.254130.232.7.25562
33130.232.8.0/26130.232.8.1 to 130.232.8.62130.232.8.6362
34130.232.8.64/26130.232.8.65 to 130.232.8.126130.232.8.12762
35130.232.8.128/26130.232.8.129 to 130.232.8.190130.232.8.19162
36130.232.8.192/26130.232.8.193 to 130.232.8.254130.232.8.25562
37130.232.9.0/26130.232.9.1 to 130.232.9.62130.232.9.6362
38130.232.9.64/26130.232.9.65 to 130.232.9.126130.232.9.12762
39130.232.9.128/26130.232.9.129 to 130.232.9.190130.232.9.19162
40130.232.9.192/26130.232.9.193 to 130.232.9.254130.232.9.25562
41130.232.10.0/26130.232.10.1 to 130.232.10.62130.232.10.6362
42130.232.10.64/26130.232.10.65 to 130.232.10.126130.232.10.12762
43130.232.10.128/26130.232.10.129 to 130.232.10.190130.232.10.19162
44130.232.10.192/26130.232.10.193 to 130.232.10.254130.232.10.25562
45130.232.11.0/26130.232.11.1 to 130.232.11.62130.232.11.6362
46130.232.11.64/26130.232.11.65 to 130.232.11.126130.232.11.12762
47130.232.11.128/26130.232.11.129 to 130.232.11.190130.232.11.19162
48130.232.11.192/26130.232.11.193 to 130.232.11.254130.232.11.25562
49130.232.12.0/26130.232.12.1 to 130.232.12.62130.232.12.6362
50130.232.12.64/26130.232.12.65 to 130.232.12.126130.232.12.12762
51130.232.12.128/26130.232.12.129 to 130.232.12.190130.232.12.19162
52130.232.12.192/26130.232.12.193 to 130.232.12.254130.232.12.25562
53130.232.13.0/26130.232.13.1 to 130.232.13.62130.232.13.6362
54130.232.13.64/26130.232.13.65 to 130.232.13.126130.232.13.12762
55130.232.13.128/26130.232.13.129 to 130.232.13.190130.232.13.19162
56130.232.13.192/26130.232.13.193 to 130.232.13.254130.232.13.25562
57130.232.14.0/26130.232.14.1 to 130.232.14.62130.232.14.6362
58130.232.14.64/26130.232.14.65 to 130.232.14.126130.232.14.12762
59130.232.14.128/26130.232.14.129 to 130.232.14.190130.232.14.19162
60130.232.14.192/26130.232.14.193 to 130.232.14.254130.232.14.25562
61130.232.15.0/26130.232.15.1 to 130.232.15.62130.232.15.6362
62130.232.15.64/26130.232.15.65 to 130.232.15.126130.232.15.12762
63130.232.15.128/26130.232.15.129 to 130.232.15.190130.232.15.19162
64130.232.15.192/26130.232.15.193 to 130.232.15.254130.232.15.25562
65130.232.16.0/26130.232.16.1 to 130.232.16.62130.232.16.6362
66130.232.16.64/26130.232.16.65 to 130.232.16.126130.232.16.12762
67130.232.16.128/26130.232.16.129 to 130.232.16.190130.232.16.19162
68130.232.16.192/26130.232.16.193 to 130.232.16.254130.232.16.25562
69130.232.17.0/26130.232.17.1 to 130.232.17.62130.232.17.6362
70130.232.17.64/26130.232.17.65 to 130.232.17.126130.232.17.12762
71130.232.17.128/26130.232.17.129 to 130.232.17.190130.232.17.19162
72130.232.17.192/26130.232.17.193 to 130.232.17.254130.232.17.25562
73130.232.18.0/26130.232.18.1 to 130.232.18.62130.232.18.6362
74130.232.18.64/26130.232.18.65 to 130.232.18.126130.232.18.12762
75130.232.18.128/26130.232.18.129 to 130.232.18.190130.232.18.19162
76130.232.18.192/26130.232.18.193 to 130.232.18.254130.232.18.25562
77130.232.19.0/26130.232.19.1 to 130.232.19.62130.232.19.6362
78130.232.19.64/26130.232.19.65 to 130.232.19.126130.232.19.12762
79130.232.19.128/26130.232.19.129 to 130.232.19.190130.232.19.19162
80130.232.19.192/26130.232.19.193 to 130.232.19.254130.232.19.25562
81130.232.20.0/26130.232.20.1 to 130.232.20.62130.232.20.6362
82130.232.20.64/26130.232.20.65 to 130.232.20.126130.232.20.12762
83130.232.20.128/26130.232.20.129 to 130.232.20.190130.232.20.19162
84130.232.20.192/26130.232.20.193 to 130.232.20.254130.232.20.25562
85130.232.21.0/26130.232.21.1 to 130.232.21.62130.232.21.6362
86130.232.21.64/26130.232.21.65 to 130.232.21.126130.232.21.12762
87130.232.21.128/26130.232.21.129 to 130.232.21.190130.232.21.19162
88130.232.21.192/26130.232.21.193 to 130.232.21.254130.232.21.25562
89130.232.22.0/26130.232.22.1 to 130.232.22.62130.232.22.6362
90130.232.22.64/26130.232.22.65 to 130.232.22.126130.232.22.12762
91130.232.22.128/26130.232.22.129 to 130.232.22.190130.232.22.19162
92130.232.22.192/26130.232.22.193 to 130.232.22.254130.232.22.25562
93130.232.23.0/26130.232.23.1 to 130.232.23.62130.232.23.6362
94130.232.23.64/26130.232.23.65 to 130.232.23.126130.232.23.12762
95130.232.23.128/26130.232.23.129 to 130.232.23.190130.232.23.19162
96130.232.23.192/26130.232.23.193 to 130.232.23.254130.232.23.25562
97130.232.24.0/26130.232.24.1 to 130.232.24.62130.232.24.6362
98130.232.24.64/26130.232.24.65 to 130.232.24.126130.232.24.12762
99130.232.24.128/26130.232.24.129 to 130.232.24.190130.232.24.19162
100130.232.24.192/26130.232.24.193 to 130.232.24.254130.232.24.25562
101130.232.25.0/26130.232.25.1 to 130.232.25.62130.232.25.6362
102130.232.25.64/26130.232.25.65 to 130.232.25.126130.232.25.12762
103130.232.25.128/26130.232.25.129 to 130.232.25.190130.232.25.19162
104130.232.25.192/26130.232.25.193 to 130.232.25.254130.232.25.25562
105130.232.26.0/26130.232.26.1 to 130.232.26.62130.232.26.6362
106130.232.26.64/26130.232.26.65 to 130.232.26.126130.232.26.12762
107130.232.26.128/26130.232.26.129 to 130.232.26.190130.232.26.19162
108130.232.26.192/26130.232.26.193 to 130.232.26.254130.232.26.25562
109130.232.27.0/26130.232.27.1 to 130.232.27.62130.232.27.6362
110130.232.27.64/26130.232.27.65 to 130.232.27.126130.232.27.12762
111130.232.27.128/26130.232.27.129 to 130.232.27.190130.232.27.19162
112130.232.27.192/26130.232.27.193 to 130.232.27.254130.232.27.25562
113130.232.28.0/26130.232.28.1 to 130.232.28.62130.232.28.6362
114130.232.28.64/26130.232.28.65 to 130.232.28.126130.232.28.12762
115130.232.28.128/26130.232.28.129 to 130.232.28.190130.232.28.19162
116130.232.28.192/26130.232.28.193 to 130.232.28.254130.232.28.25562
117130.232.29.0/26130.232.29.1 to 130.232.29.62130.232.29.6362
118130.232.29.64/26130.232.29.65 to 130.232.29.126130.232.29.12762
119130.232.29.128/26130.232.29.129 to 130.232.29.190130.232.29.19162
120130.232.29.192/26130.232.29.193 to 130.232.29.254130.232.29.25562
121130.232.30.0/26130.232.30.1 to 130.232.30.62130.232.30.6362
122130.232.30.64/26130.232.30.65 to 130.232.30.126130.232.30.12762
123130.232.30.128/26130.232.30.129 to 130.232.30.190130.232.30.19162
124130.232.30.192/26130.232.30.193 to 130.232.30.254130.232.30.25562
125130.232.31.0/26130.232.31.1 to 130.232.31.62130.232.31.6362
126130.232.31.64/26130.232.31.65 to 130.232.31.126130.232.31.12762
127130.232.31.128/26130.232.31.129 to 130.232.31.190130.232.31.19162
128130.232.31.192/26130.232.31.193 to 130.232.31.254130.232.31.25562
129130.232.32.0/26130.232.32.1 to 130.232.32.62130.232.32.6362
130130.232.32.64/26130.232.32.65 to 130.232.32.126130.232.32.12762
131130.232.32.128/26130.232.32.129 to 130.232.32.190130.232.32.19162
132130.232.32.192/26130.232.32.193 to 130.232.32.254130.232.32.25562
133130.232.33.0/26130.232.33.1 to 130.232.33.62130.232.33.6362
134130.232.33.64/26130.232.33.65 to 130.232.33.126130.232.33.12762
135130.232.33.128/26130.232.33.129 to 130.232.33.190130.232.33.19162
136130.232.33.192/26130.232.33.193 to 130.232.33.254130.232.33.25562
137130.232.34.0/26130.232.34.1 to 130.232.34.62130.232.34.6362
138130.232.34.64/26130.232.34.65 to 130.232.34.126130.232.34.12762
139130.232.34.128/26130.232.34.129 to 130.232.34.190130.232.34.19162
140130.232.34.192/26130.232.34.193 to 130.232.34.254130.232.34.25562
141130.232.35.0/26130.232.35.1 to 130.232.35.62130.232.35.6362
142130.232.35.64/26130.232.35.65 to 130.232.35.126130.232.35.12762
143130.232.35.128/26130.232.35.129 to 130.232.35.190130.232.35.19162
144130.232.35.192/26130.232.35.193 to 130.232.35.254130.232.35.25562
145130.232.36.0/26130.232.36.1 to 130.232.36.62130.232.36.6362
146130.232.36.64/26130.232.36.65 to 130.232.36.126130.232.36.12762
147130.232.36.128/26130.232.36.129 to 130.232.36.190130.232.36.19162
148130.232.36.192/26130.232.36.193 to 130.232.36.254130.232.36.25562
149130.232.37.0/26130.232.37.1 to 130.232.37.62130.232.37.6362
150130.232.37.64/26130.232.37.65 to 130.232.37.126130.232.37.12762
151130.232.37.128/26130.232.37.129 to 130.232.37.190130.232.37.19162
152130.232.37.192/26130.232.37.193 to 130.232.37.254130.232.37.25562
153130.232.38.0/26130.232.38.1 to 130.232.38.62130.232.38.6362
154130.232.38.64/26130.232.38.65 to 130.232.38.126130.232.38.12762
155130.232.38.128/26130.232.38.129 to 130.232.38.190130.232.38.19162
156130.232.38.192/26130.232.38.193 to 130.232.38.254130.232.38.25562
157130.232.39.0/26130.232.39.1 to 130.232.39.62130.232.39.6362
158130.232.39.64/26130.232.39.65 to 130.232.39.126130.232.39.12762
159130.232.39.128/26130.232.39.129 to 130.232.39.190130.232.39.19162
160130.232.39.192/26130.232.39.193 to 130.232.39.254130.232.39.25562
161130.232.40.0/26130.232.40.1 to 130.232.40.62130.232.40.6362
162130.232.40.64/26130.232.40.65 to 130.232.40.126130.232.40.12762
163130.232.40.128/26130.232.40.129 to 130.232.40.190130.232.40.19162
164130.232.40.192/26130.232.40.193 to 130.232.40.254130.232.40.25562
165130.232.41.0/26130.232.41.1 to 130.232.41.62130.232.41.6362
166130.232.41.64/26130.232.41.65 to 130.232.41.126130.232.41.12762
167130.232.41.128/26130.232.41.129 to 130.232.41.190130.232.41.19162
168130.232.41.192/26130.232.41.193 to 130.232.41.254130.232.41.25562
169130.232.42.0/26130.232.42.1 to 130.232.42.62130.232.42.6362
170130.232.42.64/26130.232.42.65 to 130.232.42.126130.232.42.12762
171130.232.42.128/26130.232.42.129 to 130.232.42.190130.232.42.19162
172130.232.42.192/26130.232.42.193 to 130.232.42.254130.232.42.25562
173130.232.43.0/26130.232.43.1 to 130.232.43.62130.232.43.6362
174130.232.43.64/26130.232.43.65 to 130.232.43.126130.232.43.12762
175130.232.43.128/26130.232.43.129 to 130.232.43.190130.232.43.19162
176130.232.43.192/26130.232.43.193 to 130.232.43.254130.232.43.25562
177130.232.44.0/26130.232.44.1 to 130.232.44.62130.232.44.6362
178130.232.44.64/26130.232.44.65 to 130.232.44.126130.232.44.12762
179130.232.44.128/26130.232.44.129 to 130.232.44.190130.232.44.19162
180130.232.44.192/26130.232.44.193 to 130.232.44.254130.232.44.25562
181130.232.45.0/26130.232.45.1 to 130.232.45.62130.232.45.6362
182130.232.45.64/26130.232.45.65 to 130.232.45.126130.232.45.12762
183130.232.45.128/26130.232.45.129 to 130.232.45.190130.232.45.19162
184130.232.45.192/26130.232.45.193 to 130.232.45.254130.232.45.25562
185130.232.46.0/26130.232.46.1 to 130.232.46.62130.232.46.6362
186130.232.46.64/26130.232.46.65 to 130.232.46.126130.232.46.12762
187130.232.46.128/26130.232.46.129 to 130.232.46.190130.232.46.19162
188130.232.46.192/26130.232.46.193 to 130.232.46.254130.232.46.25562
189130.232.47.0/26130.232.47.1 to 130.232.47.62130.232.47.6362
190130.232.47.64/26130.232.47.65 to 130.232.47.126130.232.47.12762
191130.232.47.128/26130.232.47.129 to 130.232.47.190130.232.47.19162
192130.232.47.192/26130.232.47.193 to 130.232.47.254130.232.47.25562
193130.232.48.0/26130.232.48.1 to 130.232.48.62130.232.48.6362
194130.232.48.64/26130.232.48.65 to 130.232.48.126130.232.48.12762
195130.232.48.128/26130.232.48.129 to 130.232.48.190130.232.48.19162
196130.232.48.192/26130.232.48.193 to 130.232.48.254130.232.48.25562
197130.232.49.0/26130.232.49.1 to 130.232.49.62130.232.49.6362
198130.232.49.64/26130.232.49.65 to 130.232.49.126130.232.49.12762
199130.232.49.128/26130.232.49.129 to 130.232.49.190130.232.49.19162
200130.232.49.192/26130.232.49.193 to 130.232.49.254130.232.49.25562
201130.232.50.0/26130.232.50.1 to 130.232.50.62130.232.50.6362
202130.232.50.64/26130.232.50.65 to 130.232.50.126130.232.50.12762
203130.232.50.128/26130.232.50.129 to 130.232.50.190130.232.50.19162
204130.232.50.192/26130.232.50.193 to 130.232.50.254130.232.50.25562
205130.232.51.0/26130.232.51.1 to 130.232.51.62130.232.51.6362
206130.232.51.64/26130.232.51.65 to 130.232.51.126130.232.51.12762
207130.232.51.128/26130.232.51.129 to 130.232.51.190130.232.51.19162
208130.232.51.192/26130.232.51.193 to 130.232.51.254130.232.51.25562
209130.232.52.0/26130.232.52.1 to 130.232.52.62130.232.52.6362
210130.232.52.64/26130.232.52.65 to 130.232.52.126130.232.52.12762
211130.232.52.128/26130.232.52.129 to 130.232.52.190130.232.52.19162
212130.232.52.192/26130.232.52.193 to 130.232.52.254130.232.52.25562
213130.232.53.0/26130.232.53.1 to 130.232.53.62130.232.53.6362
214130.232.53.64/26130.232.53.65 to 130.232.53.126130.232.53.12762
215130.232.53.128/26130.232.53.129 to 130.232.53.190130.232.53.19162
216130.232.53.192/26130.232.53.193 to 130.232.53.254130.232.53.25562
217130.232.54.0/26130.232.54.1 to 130.232.54.62130.232.54.6362
218130.232.54.64/26130.232.54.65 to 130.232.54.126130.232.54.12762
219130.232.54.128/26130.232.54.129 to 130.232.54.190130.232.54.19162
220130.232.54.192/26130.232.54.193 to 130.232.54.254130.232.54.25562
221130.232.55.0/26130.232.55.1 to 130.232.55.62130.232.55.6362
222130.232.55.64/26130.232.55.65 to 130.232.55.126130.232.55.12762
223130.232.55.128/26130.232.55.129 to 130.232.55.190130.232.55.19162
224130.232.55.192/26130.232.55.193 to 130.232.55.254130.232.55.25562
225130.232.56.0/26130.232.56.1 to 130.232.56.62130.232.56.6362
226130.232.56.64/26130.232.56.65 to 130.232.56.126130.232.56.12762
227130.232.56.128/26130.232.56.129 to 130.232.56.190130.232.56.19162
228130.232.56.192/26130.232.56.193 to 130.232.56.254130.232.56.25562
229130.232.57.0/26130.232.57.1 to 130.232.57.62130.232.57.6362
230130.232.57.64/26130.232.57.65 to 130.232.57.126130.232.57.12762
231130.232.57.128/26130.232.57.129 to 130.232.57.190130.232.57.19162
232130.232.57.192/26130.232.57.193 to 130.232.57.254130.232.57.25562
233130.232.58.0/26130.232.58.1 to 130.232.58.62130.232.58.6362
234130.232.58.64/26130.232.58.65 to 130.232.58.126130.232.58.12762
235130.232.58.128/26130.232.58.129 to 130.232.58.190130.232.58.19162
236130.232.58.192/26130.232.58.193 to 130.232.58.254130.232.58.25562
237130.232.59.0/26130.232.59.1 to 130.232.59.62130.232.59.6362
238130.232.59.64/26130.232.59.65 to 130.232.59.126130.232.59.12762
239130.232.59.128/26130.232.59.129 to 130.232.59.190130.232.59.19162
240130.232.59.192/26130.232.59.193 to 130.232.59.254130.232.59.25562
241130.232.60.0/26130.232.60.1 to 130.232.60.62130.232.60.6362
242130.232.60.64/26130.232.60.65 to 130.232.60.126130.232.60.12762
243130.232.60.128/26130.232.60.129 to 130.232.60.190130.232.60.19162
244130.232.60.192/26130.232.60.193 to 130.232.60.254130.232.60.25562
245130.232.61.0/26130.232.61.1 to 130.232.61.62130.232.61.6362
246130.232.61.64/26130.232.61.65 to 130.232.61.126130.232.61.12762
247130.232.61.128/26130.232.61.129 to 130.232.61.190130.232.61.19162
248130.232.61.192/26130.232.61.193 to 130.232.61.254130.232.61.25562
249130.232.62.0/26130.232.62.1 to 130.232.62.62130.232.62.6362
250130.232.62.64/26130.232.62.65 to 130.232.62.126130.232.62.12762
251130.232.62.128/26130.232.62.129 to 130.232.62.190130.232.62.19162
252130.232.62.192/26130.232.62.193 to 130.232.62.254130.232.62.25562
253130.232.63.0/26130.232.63.1 to 130.232.63.62130.232.63.6362
254130.232.63.64/26130.232.63.65 to 130.232.63.126130.232.63.12762
255130.232.63.128/26130.232.63.129 to 130.232.63.190130.232.63.19162
256130.232.63.192/26130.232.63.193 to 130.232.63.254130.232.63.25562

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.