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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.

Network138.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
138.76.0.0
Broadcast address
138.79.255.255
First usable
138.76.0.1
Last usable
138.79.255.254
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 8A4C0000 · Integer 2320236544 to 2320498687
Reverse DNS zones
76.138.in-addr.arpa
77.138.in-addr.arpa
78.138.in-addr.arpa
79.138.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
Address10001010.01001100.00000000.00000000138.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10001010.01001100.00000000.00000000138.76.0.0
Broadcast10001010.01001111.11111111.11111111138.79.255.255
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)

138.76.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1138.76.0.0/26138.76.0.1 to 138.76.0.62138.76.0.6362
2138.76.0.64/26138.76.0.65 to 138.76.0.126138.76.0.12762
3138.76.0.128/26138.76.0.129 to 138.76.0.190138.76.0.19162
4138.76.0.192/26138.76.0.193 to 138.76.0.254138.76.0.25562
5138.76.1.0/26138.76.1.1 to 138.76.1.62138.76.1.6362
6138.76.1.64/26138.76.1.65 to 138.76.1.126138.76.1.12762
7138.76.1.128/26138.76.1.129 to 138.76.1.190138.76.1.19162
8138.76.1.192/26138.76.1.193 to 138.76.1.254138.76.1.25562
9138.76.2.0/26138.76.2.1 to 138.76.2.62138.76.2.6362
10138.76.2.64/26138.76.2.65 to 138.76.2.126138.76.2.12762
11138.76.2.128/26138.76.2.129 to 138.76.2.190138.76.2.19162
12138.76.2.192/26138.76.2.193 to 138.76.2.254138.76.2.25562
13138.76.3.0/26138.76.3.1 to 138.76.3.62138.76.3.6362
14138.76.3.64/26138.76.3.65 to 138.76.3.126138.76.3.12762
15138.76.3.128/26138.76.3.129 to 138.76.3.190138.76.3.19162
16138.76.3.192/26138.76.3.193 to 138.76.3.254138.76.3.25562
17138.76.4.0/26138.76.4.1 to 138.76.4.62138.76.4.6362
18138.76.4.64/26138.76.4.65 to 138.76.4.126138.76.4.12762
19138.76.4.128/26138.76.4.129 to 138.76.4.190138.76.4.19162
20138.76.4.192/26138.76.4.193 to 138.76.4.254138.76.4.25562
21138.76.5.0/26138.76.5.1 to 138.76.5.62138.76.5.6362
22138.76.5.64/26138.76.5.65 to 138.76.5.126138.76.5.12762
23138.76.5.128/26138.76.5.129 to 138.76.5.190138.76.5.19162
24138.76.5.192/26138.76.5.193 to 138.76.5.254138.76.5.25562
25138.76.6.0/26138.76.6.1 to 138.76.6.62138.76.6.6362
26138.76.6.64/26138.76.6.65 to 138.76.6.126138.76.6.12762
27138.76.6.128/26138.76.6.129 to 138.76.6.190138.76.6.19162
28138.76.6.192/26138.76.6.193 to 138.76.6.254138.76.6.25562
29138.76.7.0/26138.76.7.1 to 138.76.7.62138.76.7.6362
30138.76.7.64/26138.76.7.65 to 138.76.7.126138.76.7.12762
31138.76.7.128/26138.76.7.129 to 138.76.7.190138.76.7.19162
32138.76.7.192/26138.76.7.193 to 138.76.7.254138.76.7.25562
33138.76.8.0/26138.76.8.1 to 138.76.8.62138.76.8.6362
34138.76.8.64/26138.76.8.65 to 138.76.8.126138.76.8.12762
35138.76.8.128/26138.76.8.129 to 138.76.8.190138.76.8.19162
36138.76.8.192/26138.76.8.193 to 138.76.8.254138.76.8.25562
37138.76.9.0/26138.76.9.1 to 138.76.9.62138.76.9.6362
38138.76.9.64/26138.76.9.65 to 138.76.9.126138.76.9.12762
39138.76.9.128/26138.76.9.129 to 138.76.9.190138.76.9.19162
40138.76.9.192/26138.76.9.193 to 138.76.9.254138.76.9.25562
41138.76.10.0/26138.76.10.1 to 138.76.10.62138.76.10.6362
42138.76.10.64/26138.76.10.65 to 138.76.10.126138.76.10.12762
43138.76.10.128/26138.76.10.129 to 138.76.10.190138.76.10.19162
44138.76.10.192/26138.76.10.193 to 138.76.10.254138.76.10.25562
45138.76.11.0/26138.76.11.1 to 138.76.11.62138.76.11.6362
46138.76.11.64/26138.76.11.65 to 138.76.11.126138.76.11.12762
47138.76.11.128/26138.76.11.129 to 138.76.11.190138.76.11.19162
48138.76.11.192/26138.76.11.193 to 138.76.11.254138.76.11.25562
49138.76.12.0/26138.76.12.1 to 138.76.12.62138.76.12.6362
50138.76.12.64/26138.76.12.65 to 138.76.12.126138.76.12.12762
51138.76.12.128/26138.76.12.129 to 138.76.12.190138.76.12.19162
52138.76.12.192/26138.76.12.193 to 138.76.12.254138.76.12.25562
53138.76.13.0/26138.76.13.1 to 138.76.13.62138.76.13.6362
54138.76.13.64/26138.76.13.65 to 138.76.13.126138.76.13.12762
55138.76.13.128/26138.76.13.129 to 138.76.13.190138.76.13.19162
56138.76.13.192/26138.76.13.193 to 138.76.13.254138.76.13.25562
57138.76.14.0/26138.76.14.1 to 138.76.14.62138.76.14.6362
58138.76.14.64/26138.76.14.65 to 138.76.14.126138.76.14.12762
59138.76.14.128/26138.76.14.129 to 138.76.14.190138.76.14.19162
60138.76.14.192/26138.76.14.193 to 138.76.14.254138.76.14.25562
61138.76.15.0/26138.76.15.1 to 138.76.15.62138.76.15.6362
62138.76.15.64/26138.76.15.65 to 138.76.15.126138.76.15.12762
63138.76.15.128/26138.76.15.129 to 138.76.15.190138.76.15.19162
64138.76.15.192/26138.76.15.193 to 138.76.15.254138.76.15.25562
65138.76.16.0/26138.76.16.1 to 138.76.16.62138.76.16.6362
66138.76.16.64/26138.76.16.65 to 138.76.16.126138.76.16.12762
67138.76.16.128/26138.76.16.129 to 138.76.16.190138.76.16.19162
68138.76.16.192/26138.76.16.193 to 138.76.16.254138.76.16.25562
69138.76.17.0/26138.76.17.1 to 138.76.17.62138.76.17.6362
70138.76.17.64/26138.76.17.65 to 138.76.17.126138.76.17.12762
71138.76.17.128/26138.76.17.129 to 138.76.17.190138.76.17.19162
72138.76.17.192/26138.76.17.193 to 138.76.17.254138.76.17.25562
73138.76.18.0/26138.76.18.1 to 138.76.18.62138.76.18.6362
74138.76.18.64/26138.76.18.65 to 138.76.18.126138.76.18.12762
75138.76.18.128/26138.76.18.129 to 138.76.18.190138.76.18.19162
76138.76.18.192/26138.76.18.193 to 138.76.18.254138.76.18.25562
77138.76.19.0/26138.76.19.1 to 138.76.19.62138.76.19.6362
78138.76.19.64/26138.76.19.65 to 138.76.19.126138.76.19.12762
79138.76.19.128/26138.76.19.129 to 138.76.19.190138.76.19.19162
80138.76.19.192/26138.76.19.193 to 138.76.19.254138.76.19.25562
81138.76.20.0/26138.76.20.1 to 138.76.20.62138.76.20.6362
82138.76.20.64/26138.76.20.65 to 138.76.20.126138.76.20.12762
83138.76.20.128/26138.76.20.129 to 138.76.20.190138.76.20.19162
84138.76.20.192/26138.76.20.193 to 138.76.20.254138.76.20.25562
85138.76.21.0/26138.76.21.1 to 138.76.21.62138.76.21.6362
86138.76.21.64/26138.76.21.65 to 138.76.21.126138.76.21.12762
87138.76.21.128/26138.76.21.129 to 138.76.21.190138.76.21.19162
88138.76.21.192/26138.76.21.193 to 138.76.21.254138.76.21.25562
89138.76.22.0/26138.76.22.1 to 138.76.22.62138.76.22.6362
90138.76.22.64/26138.76.22.65 to 138.76.22.126138.76.22.12762
91138.76.22.128/26138.76.22.129 to 138.76.22.190138.76.22.19162
92138.76.22.192/26138.76.22.193 to 138.76.22.254138.76.22.25562
93138.76.23.0/26138.76.23.1 to 138.76.23.62138.76.23.6362
94138.76.23.64/26138.76.23.65 to 138.76.23.126138.76.23.12762
95138.76.23.128/26138.76.23.129 to 138.76.23.190138.76.23.19162
96138.76.23.192/26138.76.23.193 to 138.76.23.254138.76.23.25562
97138.76.24.0/26138.76.24.1 to 138.76.24.62138.76.24.6362
98138.76.24.64/26138.76.24.65 to 138.76.24.126138.76.24.12762
99138.76.24.128/26138.76.24.129 to 138.76.24.190138.76.24.19162
100138.76.24.192/26138.76.24.193 to 138.76.24.254138.76.24.25562
101138.76.25.0/26138.76.25.1 to 138.76.25.62138.76.25.6362
102138.76.25.64/26138.76.25.65 to 138.76.25.126138.76.25.12762
103138.76.25.128/26138.76.25.129 to 138.76.25.190138.76.25.19162
104138.76.25.192/26138.76.25.193 to 138.76.25.254138.76.25.25562
105138.76.26.0/26138.76.26.1 to 138.76.26.62138.76.26.6362
106138.76.26.64/26138.76.26.65 to 138.76.26.126138.76.26.12762
107138.76.26.128/26138.76.26.129 to 138.76.26.190138.76.26.19162
108138.76.26.192/26138.76.26.193 to 138.76.26.254138.76.26.25562
109138.76.27.0/26138.76.27.1 to 138.76.27.62138.76.27.6362
110138.76.27.64/26138.76.27.65 to 138.76.27.126138.76.27.12762
111138.76.27.128/26138.76.27.129 to 138.76.27.190138.76.27.19162
112138.76.27.192/26138.76.27.193 to 138.76.27.254138.76.27.25562
113138.76.28.0/26138.76.28.1 to 138.76.28.62138.76.28.6362
114138.76.28.64/26138.76.28.65 to 138.76.28.126138.76.28.12762
115138.76.28.128/26138.76.28.129 to 138.76.28.190138.76.28.19162
116138.76.28.192/26138.76.28.193 to 138.76.28.254138.76.28.25562
117138.76.29.0/26138.76.29.1 to 138.76.29.62138.76.29.6362
118138.76.29.64/26138.76.29.65 to 138.76.29.126138.76.29.12762
119138.76.29.128/26138.76.29.129 to 138.76.29.190138.76.29.19162
120138.76.29.192/26138.76.29.193 to 138.76.29.254138.76.29.25562
121138.76.30.0/26138.76.30.1 to 138.76.30.62138.76.30.6362
122138.76.30.64/26138.76.30.65 to 138.76.30.126138.76.30.12762
123138.76.30.128/26138.76.30.129 to 138.76.30.190138.76.30.19162
124138.76.30.192/26138.76.30.193 to 138.76.30.254138.76.30.25562
125138.76.31.0/26138.76.31.1 to 138.76.31.62138.76.31.6362
126138.76.31.64/26138.76.31.65 to 138.76.31.126138.76.31.12762
127138.76.31.128/26138.76.31.129 to 138.76.31.190138.76.31.19162
128138.76.31.192/26138.76.31.193 to 138.76.31.254138.76.31.25562
129138.76.32.0/26138.76.32.1 to 138.76.32.62138.76.32.6362
130138.76.32.64/26138.76.32.65 to 138.76.32.126138.76.32.12762
131138.76.32.128/26138.76.32.129 to 138.76.32.190138.76.32.19162
132138.76.32.192/26138.76.32.193 to 138.76.32.254138.76.32.25562
133138.76.33.0/26138.76.33.1 to 138.76.33.62138.76.33.6362
134138.76.33.64/26138.76.33.65 to 138.76.33.126138.76.33.12762
135138.76.33.128/26138.76.33.129 to 138.76.33.190138.76.33.19162
136138.76.33.192/26138.76.33.193 to 138.76.33.254138.76.33.25562
137138.76.34.0/26138.76.34.1 to 138.76.34.62138.76.34.6362
138138.76.34.64/26138.76.34.65 to 138.76.34.126138.76.34.12762
139138.76.34.128/26138.76.34.129 to 138.76.34.190138.76.34.19162
140138.76.34.192/26138.76.34.193 to 138.76.34.254138.76.34.25562
141138.76.35.0/26138.76.35.1 to 138.76.35.62138.76.35.6362
142138.76.35.64/26138.76.35.65 to 138.76.35.126138.76.35.12762
143138.76.35.128/26138.76.35.129 to 138.76.35.190138.76.35.19162
144138.76.35.192/26138.76.35.193 to 138.76.35.254138.76.35.25562
145138.76.36.0/26138.76.36.1 to 138.76.36.62138.76.36.6362
146138.76.36.64/26138.76.36.65 to 138.76.36.126138.76.36.12762
147138.76.36.128/26138.76.36.129 to 138.76.36.190138.76.36.19162
148138.76.36.192/26138.76.36.193 to 138.76.36.254138.76.36.25562
149138.76.37.0/26138.76.37.1 to 138.76.37.62138.76.37.6362
150138.76.37.64/26138.76.37.65 to 138.76.37.126138.76.37.12762
151138.76.37.128/26138.76.37.129 to 138.76.37.190138.76.37.19162
152138.76.37.192/26138.76.37.193 to 138.76.37.254138.76.37.25562
153138.76.38.0/26138.76.38.1 to 138.76.38.62138.76.38.6362
154138.76.38.64/26138.76.38.65 to 138.76.38.126138.76.38.12762
155138.76.38.128/26138.76.38.129 to 138.76.38.190138.76.38.19162
156138.76.38.192/26138.76.38.193 to 138.76.38.254138.76.38.25562
157138.76.39.0/26138.76.39.1 to 138.76.39.62138.76.39.6362
158138.76.39.64/26138.76.39.65 to 138.76.39.126138.76.39.12762
159138.76.39.128/26138.76.39.129 to 138.76.39.190138.76.39.19162
160138.76.39.192/26138.76.39.193 to 138.76.39.254138.76.39.25562
161138.76.40.0/26138.76.40.1 to 138.76.40.62138.76.40.6362
162138.76.40.64/26138.76.40.65 to 138.76.40.126138.76.40.12762
163138.76.40.128/26138.76.40.129 to 138.76.40.190138.76.40.19162
164138.76.40.192/26138.76.40.193 to 138.76.40.254138.76.40.25562
165138.76.41.0/26138.76.41.1 to 138.76.41.62138.76.41.6362
166138.76.41.64/26138.76.41.65 to 138.76.41.126138.76.41.12762
167138.76.41.128/26138.76.41.129 to 138.76.41.190138.76.41.19162
168138.76.41.192/26138.76.41.193 to 138.76.41.254138.76.41.25562
169138.76.42.0/26138.76.42.1 to 138.76.42.62138.76.42.6362
170138.76.42.64/26138.76.42.65 to 138.76.42.126138.76.42.12762
171138.76.42.128/26138.76.42.129 to 138.76.42.190138.76.42.19162
172138.76.42.192/26138.76.42.193 to 138.76.42.254138.76.42.25562
173138.76.43.0/26138.76.43.1 to 138.76.43.62138.76.43.6362
174138.76.43.64/26138.76.43.65 to 138.76.43.126138.76.43.12762
175138.76.43.128/26138.76.43.129 to 138.76.43.190138.76.43.19162
176138.76.43.192/26138.76.43.193 to 138.76.43.254138.76.43.25562
177138.76.44.0/26138.76.44.1 to 138.76.44.62138.76.44.6362
178138.76.44.64/26138.76.44.65 to 138.76.44.126138.76.44.12762
179138.76.44.128/26138.76.44.129 to 138.76.44.190138.76.44.19162
180138.76.44.192/26138.76.44.193 to 138.76.44.254138.76.44.25562
181138.76.45.0/26138.76.45.1 to 138.76.45.62138.76.45.6362
182138.76.45.64/26138.76.45.65 to 138.76.45.126138.76.45.12762
183138.76.45.128/26138.76.45.129 to 138.76.45.190138.76.45.19162
184138.76.45.192/26138.76.45.193 to 138.76.45.254138.76.45.25562
185138.76.46.0/26138.76.46.1 to 138.76.46.62138.76.46.6362
186138.76.46.64/26138.76.46.65 to 138.76.46.126138.76.46.12762
187138.76.46.128/26138.76.46.129 to 138.76.46.190138.76.46.19162
188138.76.46.192/26138.76.46.193 to 138.76.46.254138.76.46.25562
189138.76.47.0/26138.76.47.1 to 138.76.47.62138.76.47.6362
190138.76.47.64/26138.76.47.65 to 138.76.47.126138.76.47.12762
191138.76.47.128/26138.76.47.129 to 138.76.47.190138.76.47.19162
192138.76.47.192/26138.76.47.193 to 138.76.47.254138.76.47.25562
193138.76.48.0/26138.76.48.1 to 138.76.48.62138.76.48.6362
194138.76.48.64/26138.76.48.65 to 138.76.48.126138.76.48.12762
195138.76.48.128/26138.76.48.129 to 138.76.48.190138.76.48.19162
196138.76.48.192/26138.76.48.193 to 138.76.48.254138.76.48.25562
197138.76.49.0/26138.76.49.1 to 138.76.49.62138.76.49.6362
198138.76.49.64/26138.76.49.65 to 138.76.49.126138.76.49.12762
199138.76.49.128/26138.76.49.129 to 138.76.49.190138.76.49.19162
200138.76.49.192/26138.76.49.193 to 138.76.49.254138.76.49.25562
201138.76.50.0/26138.76.50.1 to 138.76.50.62138.76.50.6362
202138.76.50.64/26138.76.50.65 to 138.76.50.126138.76.50.12762
203138.76.50.128/26138.76.50.129 to 138.76.50.190138.76.50.19162
204138.76.50.192/26138.76.50.193 to 138.76.50.254138.76.50.25562
205138.76.51.0/26138.76.51.1 to 138.76.51.62138.76.51.6362
206138.76.51.64/26138.76.51.65 to 138.76.51.126138.76.51.12762
207138.76.51.128/26138.76.51.129 to 138.76.51.190138.76.51.19162
208138.76.51.192/26138.76.51.193 to 138.76.51.254138.76.51.25562
209138.76.52.0/26138.76.52.1 to 138.76.52.62138.76.52.6362
210138.76.52.64/26138.76.52.65 to 138.76.52.126138.76.52.12762
211138.76.52.128/26138.76.52.129 to 138.76.52.190138.76.52.19162
212138.76.52.192/26138.76.52.193 to 138.76.52.254138.76.52.25562
213138.76.53.0/26138.76.53.1 to 138.76.53.62138.76.53.6362
214138.76.53.64/26138.76.53.65 to 138.76.53.126138.76.53.12762
215138.76.53.128/26138.76.53.129 to 138.76.53.190138.76.53.19162
216138.76.53.192/26138.76.53.193 to 138.76.53.254138.76.53.25562
217138.76.54.0/26138.76.54.1 to 138.76.54.62138.76.54.6362
218138.76.54.64/26138.76.54.65 to 138.76.54.126138.76.54.12762
219138.76.54.128/26138.76.54.129 to 138.76.54.190138.76.54.19162
220138.76.54.192/26138.76.54.193 to 138.76.54.254138.76.54.25562
221138.76.55.0/26138.76.55.1 to 138.76.55.62138.76.55.6362
222138.76.55.64/26138.76.55.65 to 138.76.55.126138.76.55.12762
223138.76.55.128/26138.76.55.129 to 138.76.55.190138.76.55.19162
224138.76.55.192/26138.76.55.193 to 138.76.55.254138.76.55.25562
225138.76.56.0/26138.76.56.1 to 138.76.56.62138.76.56.6362
226138.76.56.64/26138.76.56.65 to 138.76.56.126138.76.56.12762
227138.76.56.128/26138.76.56.129 to 138.76.56.190138.76.56.19162
228138.76.56.192/26138.76.56.193 to 138.76.56.254138.76.56.25562
229138.76.57.0/26138.76.57.1 to 138.76.57.62138.76.57.6362
230138.76.57.64/26138.76.57.65 to 138.76.57.126138.76.57.12762
231138.76.57.128/26138.76.57.129 to 138.76.57.190138.76.57.19162
232138.76.57.192/26138.76.57.193 to 138.76.57.254138.76.57.25562
233138.76.58.0/26138.76.58.1 to 138.76.58.62138.76.58.6362
234138.76.58.64/26138.76.58.65 to 138.76.58.126138.76.58.12762
235138.76.58.128/26138.76.58.129 to 138.76.58.190138.76.58.19162
236138.76.58.192/26138.76.58.193 to 138.76.58.254138.76.58.25562
237138.76.59.0/26138.76.59.1 to 138.76.59.62138.76.59.6362
238138.76.59.64/26138.76.59.65 to 138.76.59.126138.76.59.12762
239138.76.59.128/26138.76.59.129 to 138.76.59.190138.76.59.19162
240138.76.59.192/26138.76.59.193 to 138.76.59.254138.76.59.25562
241138.76.60.0/26138.76.60.1 to 138.76.60.62138.76.60.6362
242138.76.60.64/26138.76.60.65 to 138.76.60.126138.76.60.12762
243138.76.60.128/26138.76.60.129 to 138.76.60.190138.76.60.19162
244138.76.60.192/26138.76.60.193 to 138.76.60.254138.76.60.25562
245138.76.61.0/26138.76.61.1 to 138.76.61.62138.76.61.6362
246138.76.61.64/26138.76.61.65 to 138.76.61.126138.76.61.12762
247138.76.61.128/26138.76.61.129 to 138.76.61.190138.76.61.19162
248138.76.61.192/26138.76.61.193 to 138.76.61.254138.76.61.25562
249138.76.62.0/26138.76.62.1 to 138.76.62.62138.76.62.6362
250138.76.62.64/26138.76.62.65 to 138.76.62.126138.76.62.12762
251138.76.62.128/26138.76.62.129 to 138.76.62.190138.76.62.19162
252138.76.62.192/26138.76.62.193 to 138.76.62.254138.76.62.25562
253138.76.63.0/26138.76.63.1 to 138.76.63.62138.76.63.6362
254138.76.63.64/26138.76.63.65 to 138.76.63.126138.76.63.12762
255138.76.63.128/26138.76.63.129 to 138.76.63.190138.76.63.19162
256138.76.63.192/26138.76.63.193 to 138.76.63.254138.76.63.25562

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.