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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.

Network214.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
214.0.0.0
Broadcast address
215.255.255.255
First usable
214.0.0.1
Last usable
215.255.255.254
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
C (default /24)
As numbers
Hex D6000000 · Integer 3590324224 to 3623878655
Reverse DNS zones
214.in-addr.arpa
215.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
Address11010110.00000000.00000000.00000000214.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network11010110.00000000.00000000.00000000214.0.0.0
Broadcast11010111.11111111.11111111.11111111215.255.255.255
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)

214.0.0.0/7 makes 2,048 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1214.0.0.0/18214.0.0.1 to 214.0.63.254214.0.63.25516,382
2214.0.64.0/18214.0.64.1 to 214.0.127.254214.0.127.25516,382
3214.0.128.0/18214.0.128.1 to 214.0.191.254214.0.191.25516,382
4214.0.192.0/18214.0.192.1 to 214.0.255.254214.0.255.25516,382
5214.1.0.0/18214.1.0.1 to 214.1.63.254214.1.63.25516,382
6214.1.64.0/18214.1.64.1 to 214.1.127.254214.1.127.25516,382
7214.1.128.0/18214.1.128.1 to 214.1.191.254214.1.191.25516,382
8214.1.192.0/18214.1.192.1 to 214.1.255.254214.1.255.25516,382
9214.2.0.0/18214.2.0.1 to 214.2.63.254214.2.63.25516,382
10214.2.64.0/18214.2.64.1 to 214.2.127.254214.2.127.25516,382
11214.2.128.0/18214.2.128.1 to 214.2.191.254214.2.191.25516,382
12214.2.192.0/18214.2.192.1 to 214.2.255.254214.2.255.25516,382
13214.3.0.0/18214.3.0.1 to 214.3.63.254214.3.63.25516,382
14214.3.64.0/18214.3.64.1 to 214.3.127.254214.3.127.25516,382
15214.3.128.0/18214.3.128.1 to 214.3.191.254214.3.191.25516,382
16214.3.192.0/18214.3.192.1 to 214.3.255.254214.3.255.25516,382
17214.4.0.0/18214.4.0.1 to 214.4.63.254214.4.63.25516,382
18214.4.64.0/18214.4.64.1 to 214.4.127.254214.4.127.25516,382
19214.4.128.0/18214.4.128.1 to 214.4.191.254214.4.191.25516,382
20214.4.192.0/18214.4.192.1 to 214.4.255.254214.4.255.25516,382
21214.5.0.0/18214.5.0.1 to 214.5.63.254214.5.63.25516,382
22214.5.64.0/18214.5.64.1 to 214.5.127.254214.5.127.25516,382
23214.5.128.0/18214.5.128.1 to 214.5.191.254214.5.191.25516,382
24214.5.192.0/18214.5.192.1 to 214.5.255.254214.5.255.25516,382
25214.6.0.0/18214.6.0.1 to 214.6.63.254214.6.63.25516,382
26214.6.64.0/18214.6.64.1 to 214.6.127.254214.6.127.25516,382
27214.6.128.0/18214.6.128.1 to 214.6.191.254214.6.191.25516,382
28214.6.192.0/18214.6.192.1 to 214.6.255.254214.6.255.25516,382
29214.7.0.0/18214.7.0.1 to 214.7.63.254214.7.63.25516,382
30214.7.64.0/18214.7.64.1 to 214.7.127.254214.7.127.25516,382
31214.7.128.0/18214.7.128.1 to 214.7.191.254214.7.191.25516,382
32214.7.192.0/18214.7.192.1 to 214.7.255.254214.7.255.25516,382
33214.8.0.0/18214.8.0.1 to 214.8.63.254214.8.63.25516,382
34214.8.64.0/18214.8.64.1 to 214.8.127.254214.8.127.25516,382
35214.8.128.0/18214.8.128.1 to 214.8.191.254214.8.191.25516,382
36214.8.192.0/18214.8.192.1 to 214.8.255.254214.8.255.25516,382
37214.9.0.0/18214.9.0.1 to 214.9.63.254214.9.63.25516,382
38214.9.64.0/18214.9.64.1 to 214.9.127.254214.9.127.25516,382
39214.9.128.0/18214.9.128.1 to 214.9.191.254214.9.191.25516,382
40214.9.192.0/18214.9.192.1 to 214.9.255.254214.9.255.25516,382
41214.10.0.0/18214.10.0.1 to 214.10.63.254214.10.63.25516,382
42214.10.64.0/18214.10.64.1 to 214.10.127.254214.10.127.25516,382
43214.10.128.0/18214.10.128.1 to 214.10.191.254214.10.191.25516,382
44214.10.192.0/18214.10.192.1 to 214.10.255.254214.10.255.25516,382
45214.11.0.0/18214.11.0.1 to 214.11.63.254214.11.63.25516,382
46214.11.64.0/18214.11.64.1 to 214.11.127.254214.11.127.25516,382
47214.11.128.0/18214.11.128.1 to 214.11.191.254214.11.191.25516,382
48214.11.192.0/18214.11.192.1 to 214.11.255.254214.11.255.25516,382
49214.12.0.0/18214.12.0.1 to 214.12.63.254214.12.63.25516,382
50214.12.64.0/18214.12.64.1 to 214.12.127.254214.12.127.25516,382
51214.12.128.0/18214.12.128.1 to 214.12.191.254214.12.191.25516,382
52214.12.192.0/18214.12.192.1 to 214.12.255.254214.12.255.25516,382
53214.13.0.0/18214.13.0.1 to 214.13.63.254214.13.63.25516,382
54214.13.64.0/18214.13.64.1 to 214.13.127.254214.13.127.25516,382
55214.13.128.0/18214.13.128.1 to 214.13.191.254214.13.191.25516,382
56214.13.192.0/18214.13.192.1 to 214.13.255.254214.13.255.25516,382
57214.14.0.0/18214.14.0.1 to 214.14.63.254214.14.63.25516,382
58214.14.64.0/18214.14.64.1 to 214.14.127.254214.14.127.25516,382
59214.14.128.0/18214.14.128.1 to 214.14.191.254214.14.191.25516,382
60214.14.192.0/18214.14.192.1 to 214.14.255.254214.14.255.25516,382
61214.15.0.0/18214.15.0.1 to 214.15.63.254214.15.63.25516,382
62214.15.64.0/18214.15.64.1 to 214.15.127.254214.15.127.25516,382
63214.15.128.0/18214.15.128.1 to 214.15.191.254214.15.191.25516,382
64214.15.192.0/18214.15.192.1 to 214.15.255.254214.15.255.25516,382
65214.16.0.0/18214.16.0.1 to 214.16.63.254214.16.63.25516,382
66214.16.64.0/18214.16.64.1 to 214.16.127.254214.16.127.25516,382
67214.16.128.0/18214.16.128.1 to 214.16.191.254214.16.191.25516,382
68214.16.192.0/18214.16.192.1 to 214.16.255.254214.16.255.25516,382
69214.17.0.0/18214.17.0.1 to 214.17.63.254214.17.63.25516,382
70214.17.64.0/18214.17.64.1 to 214.17.127.254214.17.127.25516,382
71214.17.128.0/18214.17.128.1 to 214.17.191.254214.17.191.25516,382
72214.17.192.0/18214.17.192.1 to 214.17.255.254214.17.255.25516,382
73214.18.0.0/18214.18.0.1 to 214.18.63.254214.18.63.25516,382
74214.18.64.0/18214.18.64.1 to 214.18.127.254214.18.127.25516,382
75214.18.128.0/18214.18.128.1 to 214.18.191.254214.18.191.25516,382
76214.18.192.0/18214.18.192.1 to 214.18.255.254214.18.255.25516,382
77214.19.0.0/18214.19.0.1 to 214.19.63.254214.19.63.25516,382
78214.19.64.0/18214.19.64.1 to 214.19.127.254214.19.127.25516,382
79214.19.128.0/18214.19.128.1 to 214.19.191.254214.19.191.25516,382
80214.19.192.0/18214.19.192.1 to 214.19.255.254214.19.255.25516,382
81214.20.0.0/18214.20.0.1 to 214.20.63.254214.20.63.25516,382
82214.20.64.0/18214.20.64.1 to 214.20.127.254214.20.127.25516,382
83214.20.128.0/18214.20.128.1 to 214.20.191.254214.20.191.25516,382
84214.20.192.0/18214.20.192.1 to 214.20.255.254214.20.255.25516,382
85214.21.0.0/18214.21.0.1 to 214.21.63.254214.21.63.25516,382
86214.21.64.0/18214.21.64.1 to 214.21.127.254214.21.127.25516,382
87214.21.128.0/18214.21.128.1 to 214.21.191.254214.21.191.25516,382
88214.21.192.0/18214.21.192.1 to 214.21.255.254214.21.255.25516,382
89214.22.0.0/18214.22.0.1 to 214.22.63.254214.22.63.25516,382
90214.22.64.0/18214.22.64.1 to 214.22.127.254214.22.127.25516,382
91214.22.128.0/18214.22.128.1 to 214.22.191.254214.22.191.25516,382
92214.22.192.0/18214.22.192.1 to 214.22.255.254214.22.255.25516,382
93214.23.0.0/18214.23.0.1 to 214.23.63.254214.23.63.25516,382
94214.23.64.0/18214.23.64.1 to 214.23.127.254214.23.127.25516,382
95214.23.128.0/18214.23.128.1 to 214.23.191.254214.23.191.25516,382
96214.23.192.0/18214.23.192.1 to 214.23.255.254214.23.255.25516,382
97214.24.0.0/18214.24.0.1 to 214.24.63.254214.24.63.25516,382
98214.24.64.0/18214.24.64.1 to 214.24.127.254214.24.127.25516,382
99214.24.128.0/18214.24.128.1 to 214.24.191.254214.24.191.25516,382
100214.24.192.0/18214.24.192.1 to 214.24.255.254214.24.255.25516,382
101214.25.0.0/18214.25.0.1 to 214.25.63.254214.25.63.25516,382
102214.25.64.0/18214.25.64.1 to 214.25.127.254214.25.127.25516,382
103214.25.128.0/18214.25.128.1 to 214.25.191.254214.25.191.25516,382
104214.25.192.0/18214.25.192.1 to 214.25.255.254214.25.255.25516,382
105214.26.0.0/18214.26.0.1 to 214.26.63.254214.26.63.25516,382
106214.26.64.0/18214.26.64.1 to 214.26.127.254214.26.127.25516,382
107214.26.128.0/18214.26.128.1 to 214.26.191.254214.26.191.25516,382
108214.26.192.0/18214.26.192.1 to 214.26.255.254214.26.255.25516,382
109214.27.0.0/18214.27.0.1 to 214.27.63.254214.27.63.25516,382
110214.27.64.0/18214.27.64.1 to 214.27.127.254214.27.127.25516,382
111214.27.128.0/18214.27.128.1 to 214.27.191.254214.27.191.25516,382
112214.27.192.0/18214.27.192.1 to 214.27.255.254214.27.255.25516,382
113214.28.0.0/18214.28.0.1 to 214.28.63.254214.28.63.25516,382
114214.28.64.0/18214.28.64.1 to 214.28.127.254214.28.127.25516,382
115214.28.128.0/18214.28.128.1 to 214.28.191.254214.28.191.25516,382
116214.28.192.0/18214.28.192.1 to 214.28.255.254214.28.255.25516,382
117214.29.0.0/18214.29.0.1 to 214.29.63.254214.29.63.25516,382
118214.29.64.0/18214.29.64.1 to 214.29.127.254214.29.127.25516,382
119214.29.128.0/18214.29.128.1 to 214.29.191.254214.29.191.25516,382
120214.29.192.0/18214.29.192.1 to 214.29.255.254214.29.255.25516,382
121214.30.0.0/18214.30.0.1 to 214.30.63.254214.30.63.25516,382
122214.30.64.0/18214.30.64.1 to 214.30.127.254214.30.127.25516,382
123214.30.128.0/18214.30.128.1 to 214.30.191.254214.30.191.25516,382
124214.30.192.0/18214.30.192.1 to 214.30.255.254214.30.255.25516,382
125214.31.0.0/18214.31.0.1 to 214.31.63.254214.31.63.25516,382
126214.31.64.0/18214.31.64.1 to 214.31.127.254214.31.127.25516,382
127214.31.128.0/18214.31.128.1 to 214.31.191.254214.31.191.25516,382
128214.31.192.0/18214.31.192.1 to 214.31.255.254214.31.255.25516,382
129214.32.0.0/18214.32.0.1 to 214.32.63.254214.32.63.25516,382
130214.32.64.0/18214.32.64.1 to 214.32.127.254214.32.127.25516,382
131214.32.128.0/18214.32.128.1 to 214.32.191.254214.32.191.25516,382
132214.32.192.0/18214.32.192.1 to 214.32.255.254214.32.255.25516,382
133214.33.0.0/18214.33.0.1 to 214.33.63.254214.33.63.25516,382
134214.33.64.0/18214.33.64.1 to 214.33.127.254214.33.127.25516,382
135214.33.128.0/18214.33.128.1 to 214.33.191.254214.33.191.25516,382
136214.33.192.0/18214.33.192.1 to 214.33.255.254214.33.255.25516,382
137214.34.0.0/18214.34.0.1 to 214.34.63.254214.34.63.25516,382
138214.34.64.0/18214.34.64.1 to 214.34.127.254214.34.127.25516,382
139214.34.128.0/18214.34.128.1 to 214.34.191.254214.34.191.25516,382
140214.34.192.0/18214.34.192.1 to 214.34.255.254214.34.255.25516,382
141214.35.0.0/18214.35.0.1 to 214.35.63.254214.35.63.25516,382
142214.35.64.0/18214.35.64.1 to 214.35.127.254214.35.127.25516,382
143214.35.128.0/18214.35.128.1 to 214.35.191.254214.35.191.25516,382
144214.35.192.0/18214.35.192.1 to 214.35.255.254214.35.255.25516,382
145214.36.0.0/18214.36.0.1 to 214.36.63.254214.36.63.25516,382
146214.36.64.0/18214.36.64.1 to 214.36.127.254214.36.127.25516,382
147214.36.128.0/18214.36.128.1 to 214.36.191.254214.36.191.25516,382
148214.36.192.0/18214.36.192.1 to 214.36.255.254214.36.255.25516,382
149214.37.0.0/18214.37.0.1 to 214.37.63.254214.37.63.25516,382
150214.37.64.0/18214.37.64.1 to 214.37.127.254214.37.127.25516,382
151214.37.128.0/18214.37.128.1 to 214.37.191.254214.37.191.25516,382
152214.37.192.0/18214.37.192.1 to 214.37.255.254214.37.255.25516,382
153214.38.0.0/18214.38.0.1 to 214.38.63.254214.38.63.25516,382
154214.38.64.0/18214.38.64.1 to 214.38.127.254214.38.127.25516,382
155214.38.128.0/18214.38.128.1 to 214.38.191.254214.38.191.25516,382
156214.38.192.0/18214.38.192.1 to 214.38.255.254214.38.255.25516,382
157214.39.0.0/18214.39.0.1 to 214.39.63.254214.39.63.25516,382
158214.39.64.0/18214.39.64.1 to 214.39.127.254214.39.127.25516,382
159214.39.128.0/18214.39.128.1 to 214.39.191.254214.39.191.25516,382
160214.39.192.0/18214.39.192.1 to 214.39.255.254214.39.255.25516,382
161214.40.0.0/18214.40.0.1 to 214.40.63.254214.40.63.25516,382
162214.40.64.0/18214.40.64.1 to 214.40.127.254214.40.127.25516,382
163214.40.128.0/18214.40.128.1 to 214.40.191.254214.40.191.25516,382
164214.40.192.0/18214.40.192.1 to 214.40.255.254214.40.255.25516,382
165214.41.0.0/18214.41.0.1 to 214.41.63.254214.41.63.25516,382
166214.41.64.0/18214.41.64.1 to 214.41.127.254214.41.127.25516,382
167214.41.128.0/18214.41.128.1 to 214.41.191.254214.41.191.25516,382
168214.41.192.0/18214.41.192.1 to 214.41.255.254214.41.255.25516,382
169214.42.0.0/18214.42.0.1 to 214.42.63.254214.42.63.25516,382
170214.42.64.0/18214.42.64.1 to 214.42.127.254214.42.127.25516,382
171214.42.128.0/18214.42.128.1 to 214.42.191.254214.42.191.25516,382
172214.42.192.0/18214.42.192.1 to 214.42.255.254214.42.255.25516,382
173214.43.0.0/18214.43.0.1 to 214.43.63.254214.43.63.25516,382
174214.43.64.0/18214.43.64.1 to 214.43.127.254214.43.127.25516,382
175214.43.128.0/18214.43.128.1 to 214.43.191.254214.43.191.25516,382
176214.43.192.0/18214.43.192.1 to 214.43.255.254214.43.255.25516,382
177214.44.0.0/18214.44.0.1 to 214.44.63.254214.44.63.25516,382
178214.44.64.0/18214.44.64.1 to 214.44.127.254214.44.127.25516,382
179214.44.128.0/18214.44.128.1 to 214.44.191.254214.44.191.25516,382
180214.44.192.0/18214.44.192.1 to 214.44.255.254214.44.255.25516,382
181214.45.0.0/18214.45.0.1 to 214.45.63.254214.45.63.25516,382
182214.45.64.0/18214.45.64.1 to 214.45.127.254214.45.127.25516,382
183214.45.128.0/18214.45.128.1 to 214.45.191.254214.45.191.25516,382
184214.45.192.0/18214.45.192.1 to 214.45.255.254214.45.255.25516,382
185214.46.0.0/18214.46.0.1 to 214.46.63.254214.46.63.25516,382
186214.46.64.0/18214.46.64.1 to 214.46.127.254214.46.127.25516,382
187214.46.128.0/18214.46.128.1 to 214.46.191.254214.46.191.25516,382
188214.46.192.0/18214.46.192.1 to 214.46.255.254214.46.255.25516,382
189214.47.0.0/18214.47.0.1 to 214.47.63.254214.47.63.25516,382
190214.47.64.0/18214.47.64.1 to 214.47.127.254214.47.127.25516,382
191214.47.128.0/18214.47.128.1 to 214.47.191.254214.47.191.25516,382
192214.47.192.0/18214.47.192.1 to 214.47.255.254214.47.255.25516,382
193214.48.0.0/18214.48.0.1 to 214.48.63.254214.48.63.25516,382
194214.48.64.0/18214.48.64.1 to 214.48.127.254214.48.127.25516,382
195214.48.128.0/18214.48.128.1 to 214.48.191.254214.48.191.25516,382
196214.48.192.0/18214.48.192.1 to 214.48.255.254214.48.255.25516,382
197214.49.0.0/18214.49.0.1 to 214.49.63.254214.49.63.25516,382
198214.49.64.0/18214.49.64.1 to 214.49.127.254214.49.127.25516,382
199214.49.128.0/18214.49.128.1 to 214.49.191.254214.49.191.25516,382
200214.49.192.0/18214.49.192.1 to 214.49.255.254214.49.255.25516,382
201214.50.0.0/18214.50.0.1 to 214.50.63.254214.50.63.25516,382
202214.50.64.0/18214.50.64.1 to 214.50.127.254214.50.127.25516,382
203214.50.128.0/18214.50.128.1 to 214.50.191.254214.50.191.25516,382
204214.50.192.0/18214.50.192.1 to 214.50.255.254214.50.255.25516,382
205214.51.0.0/18214.51.0.1 to 214.51.63.254214.51.63.25516,382
206214.51.64.0/18214.51.64.1 to 214.51.127.254214.51.127.25516,382
207214.51.128.0/18214.51.128.1 to 214.51.191.254214.51.191.25516,382
208214.51.192.0/18214.51.192.1 to 214.51.255.254214.51.255.25516,382
209214.52.0.0/18214.52.0.1 to 214.52.63.254214.52.63.25516,382
210214.52.64.0/18214.52.64.1 to 214.52.127.254214.52.127.25516,382
211214.52.128.0/18214.52.128.1 to 214.52.191.254214.52.191.25516,382
212214.52.192.0/18214.52.192.1 to 214.52.255.254214.52.255.25516,382
213214.53.0.0/18214.53.0.1 to 214.53.63.254214.53.63.25516,382
214214.53.64.0/18214.53.64.1 to 214.53.127.254214.53.127.25516,382
215214.53.128.0/18214.53.128.1 to 214.53.191.254214.53.191.25516,382
216214.53.192.0/18214.53.192.1 to 214.53.255.254214.53.255.25516,382
217214.54.0.0/18214.54.0.1 to 214.54.63.254214.54.63.25516,382
218214.54.64.0/18214.54.64.1 to 214.54.127.254214.54.127.25516,382
219214.54.128.0/18214.54.128.1 to 214.54.191.254214.54.191.25516,382
220214.54.192.0/18214.54.192.1 to 214.54.255.254214.54.255.25516,382
221214.55.0.0/18214.55.0.1 to 214.55.63.254214.55.63.25516,382
222214.55.64.0/18214.55.64.1 to 214.55.127.254214.55.127.25516,382
223214.55.128.0/18214.55.128.1 to 214.55.191.254214.55.191.25516,382
224214.55.192.0/18214.55.192.1 to 214.55.255.254214.55.255.25516,382
225214.56.0.0/18214.56.0.1 to 214.56.63.254214.56.63.25516,382
226214.56.64.0/18214.56.64.1 to 214.56.127.254214.56.127.25516,382
227214.56.128.0/18214.56.128.1 to 214.56.191.254214.56.191.25516,382
228214.56.192.0/18214.56.192.1 to 214.56.255.254214.56.255.25516,382
229214.57.0.0/18214.57.0.1 to 214.57.63.254214.57.63.25516,382
230214.57.64.0/18214.57.64.1 to 214.57.127.254214.57.127.25516,382
231214.57.128.0/18214.57.128.1 to 214.57.191.254214.57.191.25516,382
232214.57.192.0/18214.57.192.1 to 214.57.255.254214.57.255.25516,382
233214.58.0.0/18214.58.0.1 to 214.58.63.254214.58.63.25516,382
234214.58.64.0/18214.58.64.1 to 214.58.127.254214.58.127.25516,382
235214.58.128.0/18214.58.128.1 to 214.58.191.254214.58.191.25516,382
236214.58.192.0/18214.58.192.1 to 214.58.255.254214.58.255.25516,382
237214.59.0.0/18214.59.0.1 to 214.59.63.254214.59.63.25516,382
238214.59.64.0/18214.59.64.1 to 214.59.127.254214.59.127.25516,382
239214.59.128.0/18214.59.128.1 to 214.59.191.254214.59.191.25516,382
240214.59.192.0/18214.59.192.1 to 214.59.255.254214.59.255.25516,382
241214.60.0.0/18214.60.0.1 to 214.60.63.254214.60.63.25516,382
242214.60.64.0/18214.60.64.1 to 214.60.127.254214.60.127.25516,382
243214.60.128.0/18214.60.128.1 to 214.60.191.254214.60.191.25516,382
244214.60.192.0/18214.60.192.1 to 214.60.255.254214.60.255.25516,382
245214.61.0.0/18214.61.0.1 to 214.61.63.254214.61.63.25516,382
246214.61.64.0/18214.61.64.1 to 214.61.127.254214.61.127.25516,382
247214.61.128.0/18214.61.128.1 to 214.61.191.254214.61.191.25516,382
248214.61.192.0/18214.61.192.1 to 214.61.255.254214.61.255.25516,382
249214.62.0.0/18214.62.0.1 to 214.62.63.254214.62.63.25516,382
250214.62.64.0/18214.62.64.1 to 214.62.127.254214.62.127.25516,382
251214.62.128.0/18214.62.128.1 to 214.62.191.254214.62.191.25516,382
252214.62.192.0/18214.62.192.1 to 214.62.255.254214.62.255.25516,382
253214.63.0.0/18214.63.0.1 to 214.63.63.254214.63.63.25516,382
254214.63.64.0/18214.63.64.1 to 214.63.127.254214.63.127.25516,382
255214.63.128.0/18214.63.128.1 to 214.63.191.254214.63.191.25516,382
256214.63.192.0/18214.63.192.1 to 214.63.255.254214.63.255.25516,382

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.