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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.

Network132.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
132.0.0.0
Broadcast address
133.255.255.255
First usable
132.0.0.1
Last usable
133.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
B (default /16)
As numbers
Hex 84000000 · Integer 2214592512 to 2248146943
Reverse DNS zones
132.in-addr.arpa
133.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10000100.00000000.00000000.00000000132.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10000100.00000000.00000000.00000000132.0.0.0
Broadcast10000101.11111111.11111111.11111111133.255.255.255
Split into smaller subnets/18
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

132.0.0.0/7 makes 2,048 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1132.0.0.0/18132.0.0.1 to 132.0.63.254132.0.63.25516,382
2132.0.64.0/18132.0.64.1 to 132.0.127.254132.0.127.25516,382
3132.0.128.0/18132.0.128.1 to 132.0.191.254132.0.191.25516,382
4132.0.192.0/18132.0.192.1 to 132.0.255.254132.0.255.25516,382
5132.1.0.0/18132.1.0.1 to 132.1.63.254132.1.63.25516,382
6132.1.64.0/18132.1.64.1 to 132.1.127.254132.1.127.25516,382
7132.1.128.0/18132.1.128.1 to 132.1.191.254132.1.191.25516,382
8132.1.192.0/18132.1.192.1 to 132.1.255.254132.1.255.25516,382
9132.2.0.0/18132.2.0.1 to 132.2.63.254132.2.63.25516,382
10132.2.64.0/18132.2.64.1 to 132.2.127.254132.2.127.25516,382
11132.2.128.0/18132.2.128.1 to 132.2.191.254132.2.191.25516,382
12132.2.192.0/18132.2.192.1 to 132.2.255.254132.2.255.25516,382
13132.3.0.0/18132.3.0.1 to 132.3.63.254132.3.63.25516,382
14132.3.64.0/18132.3.64.1 to 132.3.127.254132.3.127.25516,382
15132.3.128.0/18132.3.128.1 to 132.3.191.254132.3.191.25516,382
16132.3.192.0/18132.3.192.1 to 132.3.255.254132.3.255.25516,382
17132.4.0.0/18132.4.0.1 to 132.4.63.254132.4.63.25516,382
18132.4.64.0/18132.4.64.1 to 132.4.127.254132.4.127.25516,382
19132.4.128.0/18132.4.128.1 to 132.4.191.254132.4.191.25516,382
20132.4.192.0/18132.4.192.1 to 132.4.255.254132.4.255.25516,382
21132.5.0.0/18132.5.0.1 to 132.5.63.254132.5.63.25516,382
22132.5.64.0/18132.5.64.1 to 132.5.127.254132.5.127.25516,382
23132.5.128.0/18132.5.128.1 to 132.5.191.254132.5.191.25516,382
24132.5.192.0/18132.5.192.1 to 132.5.255.254132.5.255.25516,382
25132.6.0.0/18132.6.0.1 to 132.6.63.254132.6.63.25516,382
26132.6.64.0/18132.6.64.1 to 132.6.127.254132.6.127.25516,382
27132.6.128.0/18132.6.128.1 to 132.6.191.254132.6.191.25516,382
28132.6.192.0/18132.6.192.1 to 132.6.255.254132.6.255.25516,382
29132.7.0.0/18132.7.0.1 to 132.7.63.254132.7.63.25516,382
30132.7.64.0/18132.7.64.1 to 132.7.127.254132.7.127.25516,382
31132.7.128.0/18132.7.128.1 to 132.7.191.254132.7.191.25516,382
32132.7.192.0/18132.7.192.1 to 132.7.255.254132.7.255.25516,382
33132.8.0.0/18132.8.0.1 to 132.8.63.254132.8.63.25516,382
34132.8.64.0/18132.8.64.1 to 132.8.127.254132.8.127.25516,382
35132.8.128.0/18132.8.128.1 to 132.8.191.254132.8.191.25516,382
36132.8.192.0/18132.8.192.1 to 132.8.255.254132.8.255.25516,382
37132.9.0.0/18132.9.0.1 to 132.9.63.254132.9.63.25516,382
38132.9.64.0/18132.9.64.1 to 132.9.127.254132.9.127.25516,382
39132.9.128.0/18132.9.128.1 to 132.9.191.254132.9.191.25516,382
40132.9.192.0/18132.9.192.1 to 132.9.255.254132.9.255.25516,382
41132.10.0.0/18132.10.0.1 to 132.10.63.254132.10.63.25516,382
42132.10.64.0/18132.10.64.1 to 132.10.127.254132.10.127.25516,382
43132.10.128.0/18132.10.128.1 to 132.10.191.254132.10.191.25516,382
44132.10.192.0/18132.10.192.1 to 132.10.255.254132.10.255.25516,382
45132.11.0.0/18132.11.0.1 to 132.11.63.254132.11.63.25516,382
46132.11.64.0/18132.11.64.1 to 132.11.127.254132.11.127.25516,382
47132.11.128.0/18132.11.128.1 to 132.11.191.254132.11.191.25516,382
48132.11.192.0/18132.11.192.1 to 132.11.255.254132.11.255.25516,382
49132.12.0.0/18132.12.0.1 to 132.12.63.254132.12.63.25516,382
50132.12.64.0/18132.12.64.1 to 132.12.127.254132.12.127.25516,382
51132.12.128.0/18132.12.128.1 to 132.12.191.254132.12.191.25516,382
52132.12.192.0/18132.12.192.1 to 132.12.255.254132.12.255.25516,382
53132.13.0.0/18132.13.0.1 to 132.13.63.254132.13.63.25516,382
54132.13.64.0/18132.13.64.1 to 132.13.127.254132.13.127.25516,382
55132.13.128.0/18132.13.128.1 to 132.13.191.254132.13.191.25516,382
56132.13.192.0/18132.13.192.1 to 132.13.255.254132.13.255.25516,382
57132.14.0.0/18132.14.0.1 to 132.14.63.254132.14.63.25516,382
58132.14.64.0/18132.14.64.1 to 132.14.127.254132.14.127.25516,382
59132.14.128.0/18132.14.128.1 to 132.14.191.254132.14.191.25516,382
60132.14.192.0/18132.14.192.1 to 132.14.255.254132.14.255.25516,382
61132.15.0.0/18132.15.0.1 to 132.15.63.254132.15.63.25516,382
62132.15.64.0/18132.15.64.1 to 132.15.127.254132.15.127.25516,382
63132.15.128.0/18132.15.128.1 to 132.15.191.254132.15.191.25516,382
64132.15.192.0/18132.15.192.1 to 132.15.255.254132.15.255.25516,382
65132.16.0.0/18132.16.0.1 to 132.16.63.254132.16.63.25516,382
66132.16.64.0/18132.16.64.1 to 132.16.127.254132.16.127.25516,382
67132.16.128.0/18132.16.128.1 to 132.16.191.254132.16.191.25516,382
68132.16.192.0/18132.16.192.1 to 132.16.255.254132.16.255.25516,382
69132.17.0.0/18132.17.0.1 to 132.17.63.254132.17.63.25516,382
70132.17.64.0/18132.17.64.1 to 132.17.127.254132.17.127.25516,382
71132.17.128.0/18132.17.128.1 to 132.17.191.254132.17.191.25516,382
72132.17.192.0/18132.17.192.1 to 132.17.255.254132.17.255.25516,382
73132.18.0.0/18132.18.0.1 to 132.18.63.254132.18.63.25516,382
74132.18.64.0/18132.18.64.1 to 132.18.127.254132.18.127.25516,382
75132.18.128.0/18132.18.128.1 to 132.18.191.254132.18.191.25516,382
76132.18.192.0/18132.18.192.1 to 132.18.255.254132.18.255.25516,382
77132.19.0.0/18132.19.0.1 to 132.19.63.254132.19.63.25516,382
78132.19.64.0/18132.19.64.1 to 132.19.127.254132.19.127.25516,382
79132.19.128.0/18132.19.128.1 to 132.19.191.254132.19.191.25516,382
80132.19.192.0/18132.19.192.1 to 132.19.255.254132.19.255.25516,382
81132.20.0.0/18132.20.0.1 to 132.20.63.254132.20.63.25516,382
82132.20.64.0/18132.20.64.1 to 132.20.127.254132.20.127.25516,382
83132.20.128.0/18132.20.128.1 to 132.20.191.254132.20.191.25516,382
84132.20.192.0/18132.20.192.1 to 132.20.255.254132.20.255.25516,382
85132.21.0.0/18132.21.0.1 to 132.21.63.254132.21.63.25516,382
86132.21.64.0/18132.21.64.1 to 132.21.127.254132.21.127.25516,382
87132.21.128.0/18132.21.128.1 to 132.21.191.254132.21.191.25516,382
88132.21.192.0/18132.21.192.1 to 132.21.255.254132.21.255.25516,382
89132.22.0.0/18132.22.0.1 to 132.22.63.254132.22.63.25516,382
90132.22.64.0/18132.22.64.1 to 132.22.127.254132.22.127.25516,382
91132.22.128.0/18132.22.128.1 to 132.22.191.254132.22.191.25516,382
92132.22.192.0/18132.22.192.1 to 132.22.255.254132.22.255.25516,382
93132.23.0.0/18132.23.0.1 to 132.23.63.254132.23.63.25516,382
94132.23.64.0/18132.23.64.1 to 132.23.127.254132.23.127.25516,382
95132.23.128.0/18132.23.128.1 to 132.23.191.254132.23.191.25516,382
96132.23.192.0/18132.23.192.1 to 132.23.255.254132.23.255.25516,382
97132.24.0.0/18132.24.0.1 to 132.24.63.254132.24.63.25516,382
98132.24.64.0/18132.24.64.1 to 132.24.127.254132.24.127.25516,382
99132.24.128.0/18132.24.128.1 to 132.24.191.254132.24.191.25516,382
100132.24.192.0/18132.24.192.1 to 132.24.255.254132.24.255.25516,382
101132.25.0.0/18132.25.0.1 to 132.25.63.254132.25.63.25516,382
102132.25.64.0/18132.25.64.1 to 132.25.127.254132.25.127.25516,382
103132.25.128.0/18132.25.128.1 to 132.25.191.254132.25.191.25516,382
104132.25.192.0/18132.25.192.1 to 132.25.255.254132.25.255.25516,382
105132.26.0.0/18132.26.0.1 to 132.26.63.254132.26.63.25516,382
106132.26.64.0/18132.26.64.1 to 132.26.127.254132.26.127.25516,382
107132.26.128.0/18132.26.128.1 to 132.26.191.254132.26.191.25516,382
108132.26.192.0/18132.26.192.1 to 132.26.255.254132.26.255.25516,382
109132.27.0.0/18132.27.0.1 to 132.27.63.254132.27.63.25516,382
110132.27.64.0/18132.27.64.1 to 132.27.127.254132.27.127.25516,382
111132.27.128.0/18132.27.128.1 to 132.27.191.254132.27.191.25516,382
112132.27.192.0/18132.27.192.1 to 132.27.255.254132.27.255.25516,382
113132.28.0.0/18132.28.0.1 to 132.28.63.254132.28.63.25516,382
114132.28.64.0/18132.28.64.1 to 132.28.127.254132.28.127.25516,382
115132.28.128.0/18132.28.128.1 to 132.28.191.254132.28.191.25516,382
116132.28.192.0/18132.28.192.1 to 132.28.255.254132.28.255.25516,382
117132.29.0.0/18132.29.0.1 to 132.29.63.254132.29.63.25516,382
118132.29.64.0/18132.29.64.1 to 132.29.127.254132.29.127.25516,382
119132.29.128.0/18132.29.128.1 to 132.29.191.254132.29.191.25516,382
120132.29.192.0/18132.29.192.1 to 132.29.255.254132.29.255.25516,382
121132.30.0.0/18132.30.0.1 to 132.30.63.254132.30.63.25516,382
122132.30.64.0/18132.30.64.1 to 132.30.127.254132.30.127.25516,382
123132.30.128.0/18132.30.128.1 to 132.30.191.254132.30.191.25516,382
124132.30.192.0/18132.30.192.1 to 132.30.255.254132.30.255.25516,382
125132.31.0.0/18132.31.0.1 to 132.31.63.254132.31.63.25516,382
126132.31.64.0/18132.31.64.1 to 132.31.127.254132.31.127.25516,382
127132.31.128.0/18132.31.128.1 to 132.31.191.254132.31.191.25516,382
128132.31.192.0/18132.31.192.1 to 132.31.255.254132.31.255.25516,382
129132.32.0.0/18132.32.0.1 to 132.32.63.254132.32.63.25516,382
130132.32.64.0/18132.32.64.1 to 132.32.127.254132.32.127.25516,382
131132.32.128.0/18132.32.128.1 to 132.32.191.254132.32.191.25516,382
132132.32.192.0/18132.32.192.1 to 132.32.255.254132.32.255.25516,382
133132.33.0.0/18132.33.0.1 to 132.33.63.254132.33.63.25516,382
134132.33.64.0/18132.33.64.1 to 132.33.127.254132.33.127.25516,382
135132.33.128.0/18132.33.128.1 to 132.33.191.254132.33.191.25516,382
136132.33.192.0/18132.33.192.1 to 132.33.255.254132.33.255.25516,382
137132.34.0.0/18132.34.0.1 to 132.34.63.254132.34.63.25516,382
138132.34.64.0/18132.34.64.1 to 132.34.127.254132.34.127.25516,382
139132.34.128.0/18132.34.128.1 to 132.34.191.254132.34.191.25516,382
140132.34.192.0/18132.34.192.1 to 132.34.255.254132.34.255.25516,382
141132.35.0.0/18132.35.0.1 to 132.35.63.254132.35.63.25516,382
142132.35.64.0/18132.35.64.1 to 132.35.127.254132.35.127.25516,382
143132.35.128.0/18132.35.128.1 to 132.35.191.254132.35.191.25516,382
144132.35.192.0/18132.35.192.1 to 132.35.255.254132.35.255.25516,382
145132.36.0.0/18132.36.0.1 to 132.36.63.254132.36.63.25516,382
146132.36.64.0/18132.36.64.1 to 132.36.127.254132.36.127.25516,382
147132.36.128.0/18132.36.128.1 to 132.36.191.254132.36.191.25516,382
148132.36.192.0/18132.36.192.1 to 132.36.255.254132.36.255.25516,382
149132.37.0.0/18132.37.0.1 to 132.37.63.254132.37.63.25516,382
150132.37.64.0/18132.37.64.1 to 132.37.127.254132.37.127.25516,382
151132.37.128.0/18132.37.128.1 to 132.37.191.254132.37.191.25516,382
152132.37.192.0/18132.37.192.1 to 132.37.255.254132.37.255.25516,382
153132.38.0.0/18132.38.0.1 to 132.38.63.254132.38.63.25516,382
154132.38.64.0/18132.38.64.1 to 132.38.127.254132.38.127.25516,382
155132.38.128.0/18132.38.128.1 to 132.38.191.254132.38.191.25516,382
156132.38.192.0/18132.38.192.1 to 132.38.255.254132.38.255.25516,382
157132.39.0.0/18132.39.0.1 to 132.39.63.254132.39.63.25516,382
158132.39.64.0/18132.39.64.1 to 132.39.127.254132.39.127.25516,382
159132.39.128.0/18132.39.128.1 to 132.39.191.254132.39.191.25516,382
160132.39.192.0/18132.39.192.1 to 132.39.255.254132.39.255.25516,382
161132.40.0.0/18132.40.0.1 to 132.40.63.254132.40.63.25516,382
162132.40.64.0/18132.40.64.1 to 132.40.127.254132.40.127.25516,382
163132.40.128.0/18132.40.128.1 to 132.40.191.254132.40.191.25516,382
164132.40.192.0/18132.40.192.1 to 132.40.255.254132.40.255.25516,382
165132.41.0.0/18132.41.0.1 to 132.41.63.254132.41.63.25516,382
166132.41.64.0/18132.41.64.1 to 132.41.127.254132.41.127.25516,382
167132.41.128.0/18132.41.128.1 to 132.41.191.254132.41.191.25516,382
168132.41.192.0/18132.41.192.1 to 132.41.255.254132.41.255.25516,382
169132.42.0.0/18132.42.0.1 to 132.42.63.254132.42.63.25516,382
170132.42.64.0/18132.42.64.1 to 132.42.127.254132.42.127.25516,382
171132.42.128.0/18132.42.128.1 to 132.42.191.254132.42.191.25516,382
172132.42.192.0/18132.42.192.1 to 132.42.255.254132.42.255.25516,382
173132.43.0.0/18132.43.0.1 to 132.43.63.254132.43.63.25516,382
174132.43.64.0/18132.43.64.1 to 132.43.127.254132.43.127.25516,382
175132.43.128.0/18132.43.128.1 to 132.43.191.254132.43.191.25516,382
176132.43.192.0/18132.43.192.1 to 132.43.255.254132.43.255.25516,382
177132.44.0.0/18132.44.0.1 to 132.44.63.254132.44.63.25516,382
178132.44.64.0/18132.44.64.1 to 132.44.127.254132.44.127.25516,382
179132.44.128.0/18132.44.128.1 to 132.44.191.254132.44.191.25516,382
180132.44.192.0/18132.44.192.1 to 132.44.255.254132.44.255.25516,382
181132.45.0.0/18132.45.0.1 to 132.45.63.254132.45.63.25516,382
182132.45.64.0/18132.45.64.1 to 132.45.127.254132.45.127.25516,382
183132.45.128.0/18132.45.128.1 to 132.45.191.254132.45.191.25516,382
184132.45.192.0/18132.45.192.1 to 132.45.255.254132.45.255.25516,382
185132.46.0.0/18132.46.0.1 to 132.46.63.254132.46.63.25516,382
186132.46.64.0/18132.46.64.1 to 132.46.127.254132.46.127.25516,382
187132.46.128.0/18132.46.128.1 to 132.46.191.254132.46.191.25516,382
188132.46.192.0/18132.46.192.1 to 132.46.255.254132.46.255.25516,382
189132.47.0.0/18132.47.0.1 to 132.47.63.254132.47.63.25516,382
190132.47.64.0/18132.47.64.1 to 132.47.127.254132.47.127.25516,382
191132.47.128.0/18132.47.128.1 to 132.47.191.254132.47.191.25516,382
192132.47.192.0/18132.47.192.1 to 132.47.255.254132.47.255.25516,382
193132.48.0.0/18132.48.0.1 to 132.48.63.254132.48.63.25516,382
194132.48.64.0/18132.48.64.1 to 132.48.127.254132.48.127.25516,382
195132.48.128.0/18132.48.128.1 to 132.48.191.254132.48.191.25516,382
196132.48.192.0/18132.48.192.1 to 132.48.255.254132.48.255.25516,382
197132.49.0.0/18132.49.0.1 to 132.49.63.254132.49.63.25516,382
198132.49.64.0/18132.49.64.1 to 132.49.127.254132.49.127.25516,382
199132.49.128.0/18132.49.128.1 to 132.49.191.254132.49.191.25516,382
200132.49.192.0/18132.49.192.1 to 132.49.255.254132.49.255.25516,382
201132.50.0.0/18132.50.0.1 to 132.50.63.254132.50.63.25516,382
202132.50.64.0/18132.50.64.1 to 132.50.127.254132.50.127.25516,382
203132.50.128.0/18132.50.128.1 to 132.50.191.254132.50.191.25516,382
204132.50.192.0/18132.50.192.1 to 132.50.255.254132.50.255.25516,382
205132.51.0.0/18132.51.0.1 to 132.51.63.254132.51.63.25516,382
206132.51.64.0/18132.51.64.1 to 132.51.127.254132.51.127.25516,382
207132.51.128.0/18132.51.128.1 to 132.51.191.254132.51.191.25516,382
208132.51.192.0/18132.51.192.1 to 132.51.255.254132.51.255.25516,382
209132.52.0.0/18132.52.0.1 to 132.52.63.254132.52.63.25516,382
210132.52.64.0/18132.52.64.1 to 132.52.127.254132.52.127.25516,382
211132.52.128.0/18132.52.128.1 to 132.52.191.254132.52.191.25516,382
212132.52.192.0/18132.52.192.1 to 132.52.255.254132.52.255.25516,382
213132.53.0.0/18132.53.0.1 to 132.53.63.254132.53.63.25516,382
214132.53.64.0/18132.53.64.1 to 132.53.127.254132.53.127.25516,382
215132.53.128.0/18132.53.128.1 to 132.53.191.254132.53.191.25516,382
216132.53.192.0/18132.53.192.1 to 132.53.255.254132.53.255.25516,382
217132.54.0.0/18132.54.0.1 to 132.54.63.254132.54.63.25516,382
218132.54.64.0/18132.54.64.1 to 132.54.127.254132.54.127.25516,382
219132.54.128.0/18132.54.128.1 to 132.54.191.254132.54.191.25516,382
220132.54.192.0/18132.54.192.1 to 132.54.255.254132.54.255.25516,382
221132.55.0.0/18132.55.0.1 to 132.55.63.254132.55.63.25516,382
222132.55.64.0/18132.55.64.1 to 132.55.127.254132.55.127.25516,382
223132.55.128.0/18132.55.128.1 to 132.55.191.254132.55.191.25516,382
224132.55.192.0/18132.55.192.1 to 132.55.255.254132.55.255.25516,382
225132.56.0.0/18132.56.0.1 to 132.56.63.254132.56.63.25516,382
226132.56.64.0/18132.56.64.1 to 132.56.127.254132.56.127.25516,382
227132.56.128.0/18132.56.128.1 to 132.56.191.254132.56.191.25516,382
228132.56.192.0/18132.56.192.1 to 132.56.255.254132.56.255.25516,382
229132.57.0.0/18132.57.0.1 to 132.57.63.254132.57.63.25516,382
230132.57.64.0/18132.57.64.1 to 132.57.127.254132.57.127.25516,382
231132.57.128.0/18132.57.128.1 to 132.57.191.254132.57.191.25516,382
232132.57.192.0/18132.57.192.1 to 132.57.255.254132.57.255.25516,382
233132.58.0.0/18132.58.0.1 to 132.58.63.254132.58.63.25516,382
234132.58.64.0/18132.58.64.1 to 132.58.127.254132.58.127.25516,382
235132.58.128.0/18132.58.128.1 to 132.58.191.254132.58.191.25516,382
236132.58.192.0/18132.58.192.1 to 132.58.255.254132.58.255.25516,382
237132.59.0.0/18132.59.0.1 to 132.59.63.254132.59.63.25516,382
238132.59.64.0/18132.59.64.1 to 132.59.127.254132.59.127.25516,382
239132.59.128.0/18132.59.128.1 to 132.59.191.254132.59.191.25516,382
240132.59.192.0/18132.59.192.1 to 132.59.255.254132.59.255.25516,382
241132.60.0.0/18132.60.0.1 to 132.60.63.254132.60.63.25516,382
242132.60.64.0/18132.60.64.1 to 132.60.127.254132.60.127.25516,382
243132.60.128.0/18132.60.128.1 to 132.60.191.254132.60.191.25516,382
244132.60.192.0/18132.60.192.1 to 132.60.255.254132.60.255.25516,382
245132.61.0.0/18132.61.0.1 to 132.61.63.254132.61.63.25516,382
246132.61.64.0/18132.61.64.1 to 132.61.127.254132.61.127.25516,382
247132.61.128.0/18132.61.128.1 to 132.61.191.254132.61.191.25516,382
248132.61.192.0/18132.61.192.1 to 132.61.255.254132.61.255.25516,382
249132.62.0.0/18132.62.0.1 to 132.62.63.254132.62.63.25516,382
250132.62.64.0/18132.62.64.1 to 132.62.127.254132.62.127.25516,382
251132.62.128.0/18132.62.128.1 to 132.62.191.254132.62.191.25516,382
252132.62.192.0/18132.62.192.1 to 132.62.255.254132.62.255.25516,382
253132.63.0.0/18132.63.0.1 to 132.63.63.254132.63.63.25516,382
254132.63.64.0/18132.63.64.1 to 132.63.127.254132.63.127.25516,382
255132.63.128.0/18132.63.128.1 to 132.63.191.254132.63.191.25516,382
256132.63.192.0/18132.63.192.1 to 132.63.255.254132.63.255.25516,382

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.