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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.

Network242.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
242.232.0.0
Broadcast address
242.235.255.255
First usable
242.232.0.1
Last usable
242.235.255.254
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
Reserved 240.0.0.0/4
Future use; not usable on most systems
Old class
E (reserved)
As numbers
Hex F2E80000 · Integer 4075290624 to 4075552767
Reverse DNS zones
232.242.in-addr.arpa
233.242.in-addr.arpa
234.242.in-addr.arpa
235.242.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
Address11110010.11101000.00000000.00000000242.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network11110010.11101000.00000000.00000000242.232.0.0
Broadcast11110010.11101011.11111111.11111111242.235.255.255
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)

242.232.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1242.232.0.0/26242.232.0.1 to 242.232.0.62242.232.0.6362
2242.232.0.64/26242.232.0.65 to 242.232.0.126242.232.0.12762
3242.232.0.128/26242.232.0.129 to 242.232.0.190242.232.0.19162
4242.232.0.192/26242.232.0.193 to 242.232.0.254242.232.0.25562
5242.232.1.0/26242.232.1.1 to 242.232.1.62242.232.1.6362
6242.232.1.64/26242.232.1.65 to 242.232.1.126242.232.1.12762
7242.232.1.128/26242.232.1.129 to 242.232.1.190242.232.1.19162
8242.232.1.192/26242.232.1.193 to 242.232.1.254242.232.1.25562
9242.232.2.0/26242.232.2.1 to 242.232.2.62242.232.2.6362
10242.232.2.64/26242.232.2.65 to 242.232.2.126242.232.2.12762
11242.232.2.128/26242.232.2.129 to 242.232.2.190242.232.2.19162
12242.232.2.192/26242.232.2.193 to 242.232.2.254242.232.2.25562
13242.232.3.0/26242.232.3.1 to 242.232.3.62242.232.3.6362
14242.232.3.64/26242.232.3.65 to 242.232.3.126242.232.3.12762
15242.232.3.128/26242.232.3.129 to 242.232.3.190242.232.3.19162
16242.232.3.192/26242.232.3.193 to 242.232.3.254242.232.3.25562
17242.232.4.0/26242.232.4.1 to 242.232.4.62242.232.4.6362
18242.232.4.64/26242.232.4.65 to 242.232.4.126242.232.4.12762
19242.232.4.128/26242.232.4.129 to 242.232.4.190242.232.4.19162
20242.232.4.192/26242.232.4.193 to 242.232.4.254242.232.4.25562
21242.232.5.0/26242.232.5.1 to 242.232.5.62242.232.5.6362
22242.232.5.64/26242.232.5.65 to 242.232.5.126242.232.5.12762
23242.232.5.128/26242.232.5.129 to 242.232.5.190242.232.5.19162
24242.232.5.192/26242.232.5.193 to 242.232.5.254242.232.5.25562
25242.232.6.0/26242.232.6.1 to 242.232.6.62242.232.6.6362
26242.232.6.64/26242.232.6.65 to 242.232.6.126242.232.6.12762
27242.232.6.128/26242.232.6.129 to 242.232.6.190242.232.6.19162
28242.232.6.192/26242.232.6.193 to 242.232.6.254242.232.6.25562
29242.232.7.0/26242.232.7.1 to 242.232.7.62242.232.7.6362
30242.232.7.64/26242.232.7.65 to 242.232.7.126242.232.7.12762
31242.232.7.128/26242.232.7.129 to 242.232.7.190242.232.7.19162
32242.232.7.192/26242.232.7.193 to 242.232.7.254242.232.7.25562
33242.232.8.0/26242.232.8.1 to 242.232.8.62242.232.8.6362
34242.232.8.64/26242.232.8.65 to 242.232.8.126242.232.8.12762
35242.232.8.128/26242.232.8.129 to 242.232.8.190242.232.8.19162
36242.232.8.192/26242.232.8.193 to 242.232.8.254242.232.8.25562
37242.232.9.0/26242.232.9.1 to 242.232.9.62242.232.9.6362
38242.232.9.64/26242.232.9.65 to 242.232.9.126242.232.9.12762
39242.232.9.128/26242.232.9.129 to 242.232.9.190242.232.9.19162
40242.232.9.192/26242.232.9.193 to 242.232.9.254242.232.9.25562
41242.232.10.0/26242.232.10.1 to 242.232.10.62242.232.10.6362
42242.232.10.64/26242.232.10.65 to 242.232.10.126242.232.10.12762
43242.232.10.128/26242.232.10.129 to 242.232.10.190242.232.10.19162
44242.232.10.192/26242.232.10.193 to 242.232.10.254242.232.10.25562
45242.232.11.0/26242.232.11.1 to 242.232.11.62242.232.11.6362
46242.232.11.64/26242.232.11.65 to 242.232.11.126242.232.11.12762
47242.232.11.128/26242.232.11.129 to 242.232.11.190242.232.11.19162
48242.232.11.192/26242.232.11.193 to 242.232.11.254242.232.11.25562
49242.232.12.0/26242.232.12.1 to 242.232.12.62242.232.12.6362
50242.232.12.64/26242.232.12.65 to 242.232.12.126242.232.12.12762
51242.232.12.128/26242.232.12.129 to 242.232.12.190242.232.12.19162
52242.232.12.192/26242.232.12.193 to 242.232.12.254242.232.12.25562
53242.232.13.0/26242.232.13.1 to 242.232.13.62242.232.13.6362
54242.232.13.64/26242.232.13.65 to 242.232.13.126242.232.13.12762
55242.232.13.128/26242.232.13.129 to 242.232.13.190242.232.13.19162
56242.232.13.192/26242.232.13.193 to 242.232.13.254242.232.13.25562
57242.232.14.0/26242.232.14.1 to 242.232.14.62242.232.14.6362
58242.232.14.64/26242.232.14.65 to 242.232.14.126242.232.14.12762
59242.232.14.128/26242.232.14.129 to 242.232.14.190242.232.14.19162
60242.232.14.192/26242.232.14.193 to 242.232.14.254242.232.14.25562
61242.232.15.0/26242.232.15.1 to 242.232.15.62242.232.15.6362
62242.232.15.64/26242.232.15.65 to 242.232.15.126242.232.15.12762
63242.232.15.128/26242.232.15.129 to 242.232.15.190242.232.15.19162
64242.232.15.192/26242.232.15.193 to 242.232.15.254242.232.15.25562
65242.232.16.0/26242.232.16.1 to 242.232.16.62242.232.16.6362
66242.232.16.64/26242.232.16.65 to 242.232.16.126242.232.16.12762
67242.232.16.128/26242.232.16.129 to 242.232.16.190242.232.16.19162
68242.232.16.192/26242.232.16.193 to 242.232.16.254242.232.16.25562
69242.232.17.0/26242.232.17.1 to 242.232.17.62242.232.17.6362
70242.232.17.64/26242.232.17.65 to 242.232.17.126242.232.17.12762
71242.232.17.128/26242.232.17.129 to 242.232.17.190242.232.17.19162
72242.232.17.192/26242.232.17.193 to 242.232.17.254242.232.17.25562
73242.232.18.0/26242.232.18.1 to 242.232.18.62242.232.18.6362
74242.232.18.64/26242.232.18.65 to 242.232.18.126242.232.18.12762
75242.232.18.128/26242.232.18.129 to 242.232.18.190242.232.18.19162
76242.232.18.192/26242.232.18.193 to 242.232.18.254242.232.18.25562
77242.232.19.0/26242.232.19.1 to 242.232.19.62242.232.19.6362
78242.232.19.64/26242.232.19.65 to 242.232.19.126242.232.19.12762
79242.232.19.128/26242.232.19.129 to 242.232.19.190242.232.19.19162
80242.232.19.192/26242.232.19.193 to 242.232.19.254242.232.19.25562
81242.232.20.0/26242.232.20.1 to 242.232.20.62242.232.20.6362
82242.232.20.64/26242.232.20.65 to 242.232.20.126242.232.20.12762
83242.232.20.128/26242.232.20.129 to 242.232.20.190242.232.20.19162
84242.232.20.192/26242.232.20.193 to 242.232.20.254242.232.20.25562
85242.232.21.0/26242.232.21.1 to 242.232.21.62242.232.21.6362
86242.232.21.64/26242.232.21.65 to 242.232.21.126242.232.21.12762
87242.232.21.128/26242.232.21.129 to 242.232.21.190242.232.21.19162
88242.232.21.192/26242.232.21.193 to 242.232.21.254242.232.21.25562
89242.232.22.0/26242.232.22.1 to 242.232.22.62242.232.22.6362
90242.232.22.64/26242.232.22.65 to 242.232.22.126242.232.22.12762
91242.232.22.128/26242.232.22.129 to 242.232.22.190242.232.22.19162
92242.232.22.192/26242.232.22.193 to 242.232.22.254242.232.22.25562
93242.232.23.0/26242.232.23.1 to 242.232.23.62242.232.23.6362
94242.232.23.64/26242.232.23.65 to 242.232.23.126242.232.23.12762
95242.232.23.128/26242.232.23.129 to 242.232.23.190242.232.23.19162
96242.232.23.192/26242.232.23.193 to 242.232.23.254242.232.23.25562
97242.232.24.0/26242.232.24.1 to 242.232.24.62242.232.24.6362
98242.232.24.64/26242.232.24.65 to 242.232.24.126242.232.24.12762
99242.232.24.128/26242.232.24.129 to 242.232.24.190242.232.24.19162
100242.232.24.192/26242.232.24.193 to 242.232.24.254242.232.24.25562
101242.232.25.0/26242.232.25.1 to 242.232.25.62242.232.25.6362
102242.232.25.64/26242.232.25.65 to 242.232.25.126242.232.25.12762
103242.232.25.128/26242.232.25.129 to 242.232.25.190242.232.25.19162
104242.232.25.192/26242.232.25.193 to 242.232.25.254242.232.25.25562
105242.232.26.0/26242.232.26.1 to 242.232.26.62242.232.26.6362
106242.232.26.64/26242.232.26.65 to 242.232.26.126242.232.26.12762
107242.232.26.128/26242.232.26.129 to 242.232.26.190242.232.26.19162
108242.232.26.192/26242.232.26.193 to 242.232.26.254242.232.26.25562
109242.232.27.0/26242.232.27.1 to 242.232.27.62242.232.27.6362
110242.232.27.64/26242.232.27.65 to 242.232.27.126242.232.27.12762
111242.232.27.128/26242.232.27.129 to 242.232.27.190242.232.27.19162
112242.232.27.192/26242.232.27.193 to 242.232.27.254242.232.27.25562
113242.232.28.0/26242.232.28.1 to 242.232.28.62242.232.28.6362
114242.232.28.64/26242.232.28.65 to 242.232.28.126242.232.28.12762
115242.232.28.128/26242.232.28.129 to 242.232.28.190242.232.28.19162
116242.232.28.192/26242.232.28.193 to 242.232.28.254242.232.28.25562
117242.232.29.0/26242.232.29.1 to 242.232.29.62242.232.29.6362
118242.232.29.64/26242.232.29.65 to 242.232.29.126242.232.29.12762
119242.232.29.128/26242.232.29.129 to 242.232.29.190242.232.29.19162
120242.232.29.192/26242.232.29.193 to 242.232.29.254242.232.29.25562
121242.232.30.0/26242.232.30.1 to 242.232.30.62242.232.30.6362
122242.232.30.64/26242.232.30.65 to 242.232.30.126242.232.30.12762
123242.232.30.128/26242.232.30.129 to 242.232.30.190242.232.30.19162
124242.232.30.192/26242.232.30.193 to 242.232.30.254242.232.30.25562
125242.232.31.0/26242.232.31.1 to 242.232.31.62242.232.31.6362
126242.232.31.64/26242.232.31.65 to 242.232.31.126242.232.31.12762
127242.232.31.128/26242.232.31.129 to 242.232.31.190242.232.31.19162
128242.232.31.192/26242.232.31.193 to 242.232.31.254242.232.31.25562
129242.232.32.0/26242.232.32.1 to 242.232.32.62242.232.32.6362
130242.232.32.64/26242.232.32.65 to 242.232.32.126242.232.32.12762
131242.232.32.128/26242.232.32.129 to 242.232.32.190242.232.32.19162
132242.232.32.192/26242.232.32.193 to 242.232.32.254242.232.32.25562
133242.232.33.0/26242.232.33.1 to 242.232.33.62242.232.33.6362
134242.232.33.64/26242.232.33.65 to 242.232.33.126242.232.33.12762
135242.232.33.128/26242.232.33.129 to 242.232.33.190242.232.33.19162
136242.232.33.192/26242.232.33.193 to 242.232.33.254242.232.33.25562
137242.232.34.0/26242.232.34.1 to 242.232.34.62242.232.34.6362
138242.232.34.64/26242.232.34.65 to 242.232.34.126242.232.34.12762
139242.232.34.128/26242.232.34.129 to 242.232.34.190242.232.34.19162
140242.232.34.192/26242.232.34.193 to 242.232.34.254242.232.34.25562
141242.232.35.0/26242.232.35.1 to 242.232.35.62242.232.35.6362
142242.232.35.64/26242.232.35.65 to 242.232.35.126242.232.35.12762
143242.232.35.128/26242.232.35.129 to 242.232.35.190242.232.35.19162
144242.232.35.192/26242.232.35.193 to 242.232.35.254242.232.35.25562
145242.232.36.0/26242.232.36.1 to 242.232.36.62242.232.36.6362
146242.232.36.64/26242.232.36.65 to 242.232.36.126242.232.36.12762
147242.232.36.128/26242.232.36.129 to 242.232.36.190242.232.36.19162
148242.232.36.192/26242.232.36.193 to 242.232.36.254242.232.36.25562
149242.232.37.0/26242.232.37.1 to 242.232.37.62242.232.37.6362
150242.232.37.64/26242.232.37.65 to 242.232.37.126242.232.37.12762
151242.232.37.128/26242.232.37.129 to 242.232.37.190242.232.37.19162
152242.232.37.192/26242.232.37.193 to 242.232.37.254242.232.37.25562
153242.232.38.0/26242.232.38.1 to 242.232.38.62242.232.38.6362
154242.232.38.64/26242.232.38.65 to 242.232.38.126242.232.38.12762
155242.232.38.128/26242.232.38.129 to 242.232.38.190242.232.38.19162
156242.232.38.192/26242.232.38.193 to 242.232.38.254242.232.38.25562
157242.232.39.0/26242.232.39.1 to 242.232.39.62242.232.39.6362
158242.232.39.64/26242.232.39.65 to 242.232.39.126242.232.39.12762
159242.232.39.128/26242.232.39.129 to 242.232.39.190242.232.39.19162
160242.232.39.192/26242.232.39.193 to 242.232.39.254242.232.39.25562
161242.232.40.0/26242.232.40.1 to 242.232.40.62242.232.40.6362
162242.232.40.64/26242.232.40.65 to 242.232.40.126242.232.40.12762
163242.232.40.128/26242.232.40.129 to 242.232.40.190242.232.40.19162
164242.232.40.192/26242.232.40.193 to 242.232.40.254242.232.40.25562
165242.232.41.0/26242.232.41.1 to 242.232.41.62242.232.41.6362
166242.232.41.64/26242.232.41.65 to 242.232.41.126242.232.41.12762
167242.232.41.128/26242.232.41.129 to 242.232.41.190242.232.41.19162
168242.232.41.192/26242.232.41.193 to 242.232.41.254242.232.41.25562
169242.232.42.0/26242.232.42.1 to 242.232.42.62242.232.42.6362
170242.232.42.64/26242.232.42.65 to 242.232.42.126242.232.42.12762
171242.232.42.128/26242.232.42.129 to 242.232.42.190242.232.42.19162
172242.232.42.192/26242.232.42.193 to 242.232.42.254242.232.42.25562
173242.232.43.0/26242.232.43.1 to 242.232.43.62242.232.43.6362
174242.232.43.64/26242.232.43.65 to 242.232.43.126242.232.43.12762
175242.232.43.128/26242.232.43.129 to 242.232.43.190242.232.43.19162
176242.232.43.192/26242.232.43.193 to 242.232.43.254242.232.43.25562
177242.232.44.0/26242.232.44.1 to 242.232.44.62242.232.44.6362
178242.232.44.64/26242.232.44.65 to 242.232.44.126242.232.44.12762
179242.232.44.128/26242.232.44.129 to 242.232.44.190242.232.44.19162
180242.232.44.192/26242.232.44.193 to 242.232.44.254242.232.44.25562
181242.232.45.0/26242.232.45.1 to 242.232.45.62242.232.45.6362
182242.232.45.64/26242.232.45.65 to 242.232.45.126242.232.45.12762
183242.232.45.128/26242.232.45.129 to 242.232.45.190242.232.45.19162
184242.232.45.192/26242.232.45.193 to 242.232.45.254242.232.45.25562
185242.232.46.0/26242.232.46.1 to 242.232.46.62242.232.46.6362
186242.232.46.64/26242.232.46.65 to 242.232.46.126242.232.46.12762
187242.232.46.128/26242.232.46.129 to 242.232.46.190242.232.46.19162
188242.232.46.192/26242.232.46.193 to 242.232.46.254242.232.46.25562
189242.232.47.0/26242.232.47.1 to 242.232.47.62242.232.47.6362
190242.232.47.64/26242.232.47.65 to 242.232.47.126242.232.47.12762
191242.232.47.128/26242.232.47.129 to 242.232.47.190242.232.47.19162
192242.232.47.192/26242.232.47.193 to 242.232.47.254242.232.47.25562
193242.232.48.0/26242.232.48.1 to 242.232.48.62242.232.48.6362
194242.232.48.64/26242.232.48.65 to 242.232.48.126242.232.48.12762
195242.232.48.128/26242.232.48.129 to 242.232.48.190242.232.48.19162
196242.232.48.192/26242.232.48.193 to 242.232.48.254242.232.48.25562
197242.232.49.0/26242.232.49.1 to 242.232.49.62242.232.49.6362
198242.232.49.64/26242.232.49.65 to 242.232.49.126242.232.49.12762
199242.232.49.128/26242.232.49.129 to 242.232.49.190242.232.49.19162
200242.232.49.192/26242.232.49.193 to 242.232.49.254242.232.49.25562
201242.232.50.0/26242.232.50.1 to 242.232.50.62242.232.50.6362
202242.232.50.64/26242.232.50.65 to 242.232.50.126242.232.50.12762
203242.232.50.128/26242.232.50.129 to 242.232.50.190242.232.50.19162
204242.232.50.192/26242.232.50.193 to 242.232.50.254242.232.50.25562
205242.232.51.0/26242.232.51.1 to 242.232.51.62242.232.51.6362
206242.232.51.64/26242.232.51.65 to 242.232.51.126242.232.51.12762
207242.232.51.128/26242.232.51.129 to 242.232.51.190242.232.51.19162
208242.232.51.192/26242.232.51.193 to 242.232.51.254242.232.51.25562
209242.232.52.0/26242.232.52.1 to 242.232.52.62242.232.52.6362
210242.232.52.64/26242.232.52.65 to 242.232.52.126242.232.52.12762
211242.232.52.128/26242.232.52.129 to 242.232.52.190242.232.52.19162
212242.232.52.192/26242.232.52.193 to 242.232.52.254242.232.52.25562
213242.232.53.0/26242.232.53.1 to 242.232.53.62242.232.53.6362
214242.232.53.64/26242.232.53.65 to 242.232.53.126242.232.53.12762
215242.232.53.128/26242.232.53.129 to 242.232.53.190242.232.53.19162
216242.232.53.192/26242.232.53.193 to 242.232.53.254242.232.53.25562
217242.232.54.0/26242.232.54.1 to 242.232.54.62242.232.54.6362
218242.232.54.64/26242.232.54.65 to 242.232.54.126242.232.54.12762
219242.232.54.128/26242.232.54.129 to 242.232.54.190242.232.54.19162
220242.232.54.192/26242.232.54.193 to 242.232.54.254242.232.54.25562
221242.232.55.0/26242.232.55.1 to 242.232.55.62242.232.55.6362
222242.232.55.64/26242.232.55.65 to 242.232.55.126242.232.55.12762
223242.232.55.128/26242.232.55.129 to 242.232.55.190242.232.55.19162
224242.232.55.192/26242.232.55.193 to 242.232.55.254242.232.55.25562
225242.232.56.0/26242.232.56.1 to 242.232.56.62242.232.56.6362
226242.232.56.64/26242.232.56.65 to 242.232.56.126242.232.56.12762
227242.232.56.128/26242.232.56.129 to 242.232.56.190242.232.56.19162
228242.232.56.192/26242.232.56.193 to 242.232.56.254242.232.56.25562
229242.232.57.0/26242.232.57.1 to 242.232.57.62242.232.57.6362
230242.232.57.64/26242.232.57.65 to 242.232.57.126242.232.57.12762
231242.232.57.128/26242.232.57.129 to 242.232.57.190242.232.57.19162
232242.232.57.192/26242.232.57.193 to 242.232.57.254242.232.57.25562
233242.232.58.0/26242.232.58.1 to 242.232.58.62242.232.58.6362
234242.232.58.64/26242.232.58.65 to 242.232.58.126242.232.58.12762
235242.232.58.128/26242.232.58.129 to 242.232.58.190242.232.58.19162
236242.232.58.192/26242.232.58.193 to 242.232.58.254242.232.58.25562
237242.232.59.0/26242.232.59.1 to 242.232.59.62242.232.59.6362
238242.232.59.64/26242.232.59.65 to 242.232.59.126242.232.59.12762
239242.232.59.128/26242.232.59.129 to 242.232.59.190242.232.59.19162
240242.232.59.192/26242.232.59.193 to 242.232.59.254242.232.59.25562
241242.232.60.0/26242.232.60.1 to 242.232.60.62242.232.60.6362
242242.232.60.64/26242.232.60.65 to 242.232.60.126242.232.60.12762
243242.232.60.128/26242.232.60.129 to 242.232.60.190242.232.60.19162
244242.232.60.192/26242.232.60.193 to 242.232.60.254242.232.60.25562
245242.232.61.0/26242.232.61.1 to 242.232.61.62242.232.61.6362
246242.232.61.64/26242.232.61.65 to 242.232.61.126242.232.61.12762
247242.232.61.128/26242.232.61.129 to 242.232.61.190242.232.61.19162
248242.232.61.192/26242.232.61.193 to 242.232.61.254242.232.61.25562
249242.232.62.0/26242.232.62.1 to 242.232.62.62242.232.62.6362
250242.232.62.64/26242.232.62.65 to 242.232.62.126242.232.62.12762
251242.232.62.128/26242.232.62.129 to 242.232.62.190242.232.62.19162
252242.232.62.192/26242.232.62.193 to 242.232.62.254242.232.62.25562
253242.232.63.0/26242.232.63.1 to 242.232.63.62242.232.63.6362
254242.232.63.64/26242.232.63.65 to 242.232.63.126242.232.63.12762
255242.232.63.128/26242.232.63.129 to 242.232.63.190242.232.63.19162
256242.232.63.192/26242.232.63.193 to 242.232.63.254242.232.63.25562

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.