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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.

Network214.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
214.0.0.0
Broadcast address
214.255.255.255
First usable
214.0.0.1
Last usable
214.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
C (default /24)
As numbers
Hex D6000000 · Integer 3590324224 to 3607101439
Reverse DNS zone
214.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11010110..00000000.00000000.00000000214.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network11010110..00000000.00000000.00000000214.0.0.0
Broadcast11010110..11111111.11111111.11111111214.255.255.255
Split into smaller subnets/20
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

214.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1214.0.0.0/20214.0.0.1 to 214.0.15.254214.0.15.2554,094
2214.0.16.0/20214.0.16.1 to 214.0.31.254214.0.31.2554,094
3214.0.32.0/20214.0.32.1 to 214.0.47.254214.0.47.2554,094
4214.0.48.0/20214.0.48.1 to 214.0.63.254214.0.63.2554,094
5214.0.64.0/20214.0.64.1 to 214.0.79.254214.0.79.2554,094
6214.0.80.0/20214.0.80.1 to 214.0.95.254214.0.95.2554,094
7214.0.96.0/20214.0.96.1 to 214.0.111.254214.0.111.2554,094
8214.0.112.0/20214.0.112.1 to 214.0.127.254214.0.127.2554,094
9214.0.128.0/20214.0.128.1 to 214.0.143.254214.0.143.2554,094
10214.0.144.0/20214.0.144.1 to 214.0.159.254214.0.159.2554,094
11214.0.160.0/20214.0.160.1 to 214.0.175.254214.0.175.2554,094
12214.0.176.0/20214.0.176.1 to 214.0.191.254214.0.191.2554,094
13214.0.192.0/20214.0.192.1 to 214.0.207.254214.0.207.2554,094
14214.0.208.0/20214.0.208.1 to 214.0.223.254214.0.223.2554,094
15214.0.224.0/20214.0.224.1 to 214.0.239.254214.0.239.2554,094
16214.0.240.0/20214.0.240.1 to 214.0.255.254214.0.255.2554,094
17214.1.0.0/20214.1.0.1 to 214.1.15.254214.1.15.2554,094
18214.1.16.0/20214.1.16.1 to 214.1.31.254214.1.31.2554,094
19214.1.32.0/20214.1.32.1 to 214.1.47.254214.1.47.2554,094
20214.1.48.0/20214.1.48.1 to 214.1.63.254214.1.63.2554,094
21214.1.64.0/20214.1.64.1 to 214.1.79.254214.1.79.2554,094
22214.1.80.0/20214.1.80.1 to 214.1.95.254214.1.95.2554,094
23214.1.96.0/20214.1.96.1 to 214.1.111.254214.1.111.2554,094
24214.1.112.0/20214.1.112.1 to 214.1.127.254214.1.127.2554,094
25214.1.128.0/20214.1.128.1 to 214.1.143.254214.1.143.2554,094
26214.1.144.0/20214.1.144.1 to 214.1.159.254214.1.159.2554,094
27214.1.160.0/20214.1.160.1 to 214.1.175.254214.1.175.2554,094
28214.1.176.0/20214.1.176.1 to 214.1.191.254214.1.191.2554,094
29214.1.192.0/20214.1.192.1 to 214.1.207.254214.1.207.2554,094
30214.1.208.0/20214.1.208.1 to 214.1.223.254214.1.223.2554,094
31214.1.224.0/20214.1.224.1 to 214.1.239.254214.1.239.2554,094
32214.1.240.0/20214.1.240.1 to 214.1.255.254214.1.255.2554,094
33214.2.0.0/20214.2.0.1 to 214.2.15.254214.2.15.2554,094
34214.2.16.0/20214.2.16.1 to 214.2.31.254214.2.31.2554,094
35214.2.32.0/20214.2.32.1 to 214.2.47.254214.2.47.2554,094
36214.2.48.0/20214.2.48.1 to 214.2.63.254214.2.63.2554,094
37214.2.64.0/20214.2.64.1 to 214.2.79.254214.2.79.2554,094
38214.2.80.0/20214.2.80.1 to 214.2.95.254214.2.95.2554,094
39214.2.96.0/20214.2.96.1 to 214.2.111.254214.2.111.2554,094
40214.2.112.0/20214.2.112.1 to 214.2.127.254214.2.127.2554,094
41214.2.128.0/20214.2.128.1 to 214.2.143.254214.2.143.2554,094
42214.2.144.0/20214.2.144.1 to 214.2.159.254214.2.159.2554,094
43214.2.160.0/20214.2.160.1 to 214.2.175.254214.2.175.2554,094
44214.2.176.0/20214.2.176.1 to 214.2.191.254214.2.191.2554,094
45214.2.192.0/20214.2.192.1 to 214.2.207.254214.2.207.2554,094
46214.2.208.0/20214.2.208.1 to 214.2.223.254214.2.223.2554,094
47214.2.224.0/20214.2.224.1 to 214.2.239.254214.2.239.2554,094
48214.2.240.0/20214.2.240.1 to 214.2.255.254214.2.255.2554,094
49214.3.0.0/20214.3.0.1 to 214.3.15.254214.3.15.2554,094
50214.3.16.0/20214.3.16.1 to 214.3.31.254214.3.31.2554,094
51214.3.32.0/20214.3.32.1 to 214.3.47.254214.3.47.2554,094
52214.3.48.0/20214.3.48.1 to 214.3.63.254214.3.63.2554,094
53214.3.64.0/20214.3.64.1 to 214.3.79.254214.3.79.2554,094
54214.3.80.0/20214.3.80.1 to 214.3.95.254214.3.95.2554,094
55214.3.96.0/20214.3.96.1 to 214.3.111.254214.3.111.2554,094
56214.3.112.0/20214.3.112.1 to 214.3.127.254214.3.127.2554,094
57214.3.128.0/20214.3.128.1 to 214.3.143.254214.3.143.2554,094
58214.3.144.0/20214.3.144.1 to 214.3.159.254214.3.159.2554,094
59214.3.160.0/20214.3.160.1 to 214.3.175.254214.3.175.2554,094
60214.3.176.0/20214.3.176.1 to 214.3.191.254214.3.191.2554,094
61214.3.192.0/20214.3.192.1 to 214.3.207.254214.3.207.2554,094
62214.3.208.0/20214.3.208.1 to 214.3.223.254214.3.223.2554,094
63214.3.224.0/20214.3.224.1 to 214.3.239.254214.3.239.2554,094
64214.3.240.0/20214.3.240.1 to 214.3.255.254214.3.255.2554,094
65214.4.0.0/20214.4.0.1 to 214.4.15.254214.4.15.2554,094
66214.4.16.0/20214.4.16.1 to 214.4.31.254214.4.31.2554,094
67214.4.32.0/20214.4.32.1 to 214.4.47.254214.4.47.2554,094
68214.4.48.0/20214.4.48.1 to 214.4.63.254214.4.63.2554,094
69214.4.64.0/20214.4.64.1 to 214.4.79.254214.4.79.2554,094
70214.4.80.0/20214.4.80.1 to 214.4.95.254214.4.95.2554,094
71214.4.96.0/20214.4.96.1 to 214.4.111.254214.4.111.2554,094
72214.4.112.0/20214.4.112.1 to 214.4.127.254214.4.127.2554,094
73214.4.128.0/20214.4.128.1 to 214.4.143.254214.4.143.2554,094
74214.4.144.0/20214.4.144.1 to 214.4.159.254214.4.159.2554,094
75214.4.160.0/20214.4.160.1 to 214.4.175.254214.4.175.2554,094
76214.4.176.0/20214.4.176.1 to 214.4.191.254214.4.191.2554,094
77214.4.192.0/20214.4.192.1 to 214.4.207.254214.4.207.2554,094
78214.4.208.0/20214.4.208.1 to 214.4.223.254214.4.223.2554,094
79214.4.224.0/20214.4.224.1 to 214.4.239.254214.4.239.2554,094
80214.4.240.0/20214.4.240.1 to 214.4.255.254214.4.255.2554,094
81214.5.0.0/20214.5.0.1 to 214.5.15.254214.5.15.2554,094
82214.5.16.0/20214.5.16.1 to 214.5.31.254214.5.31.2554,094
83214.5.32.0/20214.5.32.1 to 214.5.47.254214.5.47.2554,094
84214.5.48.0/20214.5.48.1 to 214.5.63.254214.5.63.2554,094
85214.5.64.0/20214.5.64.1 to 214.5.79.254214.5.79.2554,094
86214.5.80.0/20214.5.80.1 to 214.5.95.254214.5.95.2554,094
87214.5.96.0/20214.5.96.1 to 214.5.111.254214.5.111.2554,094
88214.5.112.0/20214.5.112.1 to 214.5.127.254214.5.127.2554,094
89214.5.128.0/20214.5.128.1 to 214.5.143.254214.5.143.2554,094
90214.5.144.0/20214.5.144.1 to 214.5.159.254214.5.159.2554,094
91214.5.160.0/20214.5.160.1 to 214.5.175.254214.5.175.2554,094
92214.5.176.0/20214.5.176.1 to 214.5.191.254214.5.191.2554,094
93214.5.192.0/20214.5.192.1 to 214.5.207.254214.5.207.2554,094
94214.5.208.0/20214.5.208.1 to 214.5.223.254214.5.223.2554,094
95214.5.224.0/20214.5.224.1 to 214.5.239.254214.5.239.2554,094
96214.5.240.0/20214.5.240.1 to 214.5.255.254214.5.255.2554,094
97214.6.0.0/20214.6.0.1 to 214.6.15.254214.6.15.2554,094
98214.6.16.0/20214.6.16.1 to 214.6.31.254214.6.31.2554,094
99214.6.32.0/20214.6.32.1 to 214.6.47.254214.6.47.2554,094
100214.6.48.0/20214.6.48.1 to 214.6.63.254214.6.63.2554,094
101214.6.64.0/20214.6.64.1 to 214.6.79.254214.6.79.2554,094
102214.6.80.0/20214.6.80.1 to 214.6.95.254214.6.95.2554,094
103214.6.96.0/20214.6.96.1 to 214.6.111.254214.6.111.2554,094
104214.6.112.0/20214.6.112.1 to 214.6.127.254214.6.127.2554,094
105214.6.128.0/20214.6.128.1 to 214.6.143.254214.6.143.2554,094
106214.6.144.0/20214.6.144.1 to 214.6.159.254214.6.159.2554,094
107214.6.160.0/20214.6.160.1 to 214.6.175.254214.6.175.2554,094
108214.6.176.0/20214.6.176.1 to 214.6.191.254214.6.191.2554,094
109214.6.192.0/20214.6.192.1 to 214.6.207.254214.6.207.2554,094
110214.6.208.0/20214.6.208.1 to 214.6.223.254214.6.223.2554,094
111214.6.224.0/20214.6.224.1 to 214.6.239.254214.6.239.2554,094
112214.6.240.0/20214.6.240.1 to 214.6.255.254214.6.255.2554,094
113214.7.0.0/20214.7.0.1 to 214.7.15.254214.7.15.2554,094
114214.7.16.0/20214.7.16.1 to 214.7.31.254214.7.31.2554,094
115214.7.32.0/20214.7.32.1 to 214.7.47.254214.7.47.2554,094
116214.7.48.0/20214.7.48.1 to 214.7.63.254214.7.63.2554,094
117214.7.64.0/20214.7.64.1 to 214.7.79.254214.7.79.2554,094
118214.7.80.0/20214.7.80.1 to 214.7.95.254214.7.95.2554,094
119214.7.96.0/20214.7.96.1 to 214.7.111.254214.7.111.2554,094
120214.7.112.0/20214.7.112.1 to 214.7.127.254214.7.127.2554,094
121214.7.128.0/20214.7.128.1 to 214.7.143.254214.7.143.2554,094
122214.7.144.0/20214.7.144.1 to 214.7.159.254214.7.159.2554,094
123214.7.160.0/20214.7.160.1 to 214.7.175.254214.7.175.2554,094
124214.7.176.0/20214.7.176.1 to 214.7.191.254214.7.191.2554,094
125214.7.192.0/20214.7.192.1 to 214.7.207.254214.7.207.2554,094
126214.7.208.0/20214.7.208.1 to 214.7.223.254214.7.223.2554,094
127214.7.224.0/20214.7.224.1 to 214.7.239.254214.7.239.2554,094
128214.7.240.0/20214.7.240.1 to 214.7.255.254214.7.255.2554,094
129214.8.0.0/20214.8.0.1 to 214.8.15.254214.8.15.2554,094
130214.8.16.0/20214.8.16.1 to 214.8.31.254214.8.31.2554,094
131214.8.32.0/20214.8.32.1 to 214.8.47.254214.8.47.2554,094
132214.8.48.0/20214.8.48.1 to 214.8.63.254214.8.63.2554,094
133214.8.64.0/20214.8.64.1 to 214.8.79.254214.8.79.2554,094
134214.8.80.0/20214.8.80.1 to 214.8.95.254214.8.95.2554,094
135214.8.96.0/20214.8.96.1 to 214.8.111.254214.8.111.2554,094
136214.8.112.0/20214.8.112.1 to 214.8.127.254214.8.127.2554,094
137214.8.128.0/20214.8.128.1 to 214.8.143.254214.8.143.2554,094
138214.8.144.0/20214.8.144.1 to 214.8.159.254214.8.159.2554,094
139214.8.160.0/20214.8.160.1 to 214.8.175.254214.8.175.2554,094
140214.8.176.0/20214.8.176.1 to 214.8.191.254214.8.191.2554,094
141214.8.192.0/20214.8.192.1 to 214.8.207.254214.8.207.2554,094
142214.8.208.0/20214.8.208.1 to 214.8.223.254214.8.223.2554,094
143214.8.224.0/20214.8.224.1 to 214.8.239.254214.8.239.2554,094
144214.8.240.0/20214.8.240.1 to 214.8.255.254214.8.255.2554,094
145214.9.0.0/20214.9.0.1 to 214.9.15.254214.9.15.2554,094
146214.9.16.0/20214.9.16.1 to 214.9.31.254214.9.31.2554,094
147214.9.32.0/20214.9.32.1 to 214.9.47.254214.9.47.2554,094
148214.9.48.0/20214.9.48.1 to 214.9.63.254214.9.63.2554,094
149214.9.64.0/20214.9.64.1 to 214.9.79.254214.9.79.2554,094
150214.9.80.0/20214.9.80.1 to 214.9.95.254214.9.95.2554,094
151214.9.96.0/20214.9.96.1 to 214.9.111.254214.9.111.2554,094
152214.9.112.0/20214.9.112.1 to 214.9.127.254214.9.127.2554,094
153214.9.128.0/20214.9.128.1 to 214.9.143.254214.9.143.2554,094
154214.9.144.0/20214.9.144.1 to 214.9.159.254214.9.159.2554,094
155214.9.160.0/20214.9.160.1 to 214.9.175.254214.9.175.2554,094
156214.9.176.0/20214.9.176.1 to 214.9.191.254214.9.191.2554,094
157214.9.192.0/20214.9.192.1 to 214.9.207.254214.9.207.2554,094
158214.9.208.0/20214.9.208.1 to 214.9.223.254214.9.223.2554,094
159214.9.224.0/20214.9.224.1 to 214.9.239.254214.9.239.2554,094
160214.9.240.0/20214.9.240.1 to 214.9.255.254214.9.255.2554,094
161214.10.0.0/20214.10.0.1 to 214.10.15.254214.10.15.2554,094
162214.10.16.0/20214.10.16.1 to 214.10.31.254214.10.31.2554,094
163214.10.32.0/20214.10.32.1 to 214.10.47.254214.10.47.2554,094
164214.10.48.0/20214.10.48.1 to 214.10.63.254214.10.63.2554,094
165214.10.64.0/20214.10.64.1 to 214.10.79.254214.10.79.2554,094
166214.10.80.0/20214.10.80.1 to 214.10.95.254214.10.95.2554,094
167214.10.96.0/20214.10.96.1 to 214.10.111.254214.10.111.2554,094
168214.10.112.0/20214.10.112.1 to 214.10.127.254214.10.127.2554,094
169214.10.128.0/20214.10.128.1 to 214.10.143.254214.10.143.2554,094
170214.10.144.0/20214.10.144.1 to 214.10.159.254214.10.159.2554,094
171214.10.160.0/20214.10.160.1 to 214.10.175.254214.10.175.2554,094
172214.10.176.0/20214.10.176.1 to 214.10.191.254214.10.191.2554,094
173214.10.192.0/20214.10.192.1 to 214.10.207.254214.10.207.2554,094
174214.10.208.0/20214.10.208.1 to 214.10.223.254214.10.223.2554,094
175214.10.224.0/20214.10.224.1 to 214.10.239.254214.10.239.2554,094
176214.10.240.0/20214.10.240.1 to 214.10.255.254214.10.255.2554,094
177214.11.0.0/20214.11.0.1 to 214.11.15.254214.11.15.2554,094
178214.11.16.0/20214.11.16.1 to 214.11.31.254214.11.31.2554,094
179214.11.32.0/20214.11.32.1 to 214.11.47.254214.11.47.2554,094
180214.11.48.0/20214.11.48.1 to 214.11.63.254214.11.63.2554,094
181214.11.64.0/20214.11.64.1 to 214.11.79.254214.11.79.2554,094
182214.11.80.0/20214.11.80.1 to 214.11.95.254214.11.95.2554,094
183214.11.96.0/20214.11.96.1 to 214.11.111.254214.11.111.2554,094
184214.11.112.0/20214.11.112.1 to 214.11.127.254214.11.127.2554,094
185214.11.128.0/20214.11.128.1 to 214.11.143.254214.11.143.2554,094
186214.11.144.0/20214.11.144.1 to 214.11.159.254214.11.159.2554,094
187214.11.160.0/20214.11.160.1 to 214.11.175.254214.11.175.2554,094
188214.11.176.0/20214.11.176.1 to 214.11.191.254214.11.191.2554,094
189214.11.192.0/20214.11.192.1 to 214.11.207.254214.11.207.2554,094
190214.11.208.0/20214.11.208.1 to 214.11.223.254214.11.223.2554,094
191214.11.224.0/20214.11.224.1 to 214.11.239.254214.11.239.2554,094
192214.11.240.0/20214.11.240.1 to 214.11.255.254214.11.255.2554,094
193214.12.0.0/20214.12.0.1 to 214.12.15.254214.12.15.2554,094
194214.12.16.0/20214.12.16.1 to 214.12.31.254214.12.31.2554,094
195214.12.32.0/20214.12.32.1 to 214.12.47.254214.12.47.2554,094
196214.12.48.0/20214.12.48.1 to 214.12.63.254214.12.63.2554,094
197214.12.64.0/20214.12.64.1 to 214.12.79.254214.12.79.2554,094
198214.12.80.0/20214.12.80.1 to 214.12.95.254214.12.95.2554,094
199214.12.96.0/20214.12.96.1 to 214.12.111.254214.12.111.2554,094
200214.12.112.0/20214.12.112.1 to 214.12.127.254214.12.127.2554,094
201214.12.128.0/20214.12.128.1 to 214.12.143.254214.12.143.2554,094
202214.12.144.0/20214.12.144.1 to 214.12.159.254214.12.159.2554,094
203214.12.160.0/20214.12.160.1 to 214.12.175.254214.12.175.2554,094
204214.12.176.0/20214.12.176.1 to 214.12.191.254214.12.191.2554,094
205214.12.192.0/20214.12.192.1 to 214.12.207.254214.12.207.2554,094
206214.12.208.0/20214.12.208.1 to 214.12.223.254214.12.223.2554,094
207214.12.224.0/20214.12.224.1 to 214.12.239.254214.12.239.2554,094
208214.12.240.0/20214.12.240.1 to 214.12.255.254214.12.255.2554,094
209214.13.0.0/20214.13.0.1 to 214.13.15.254214.13.15.2554,094
210214.13.16.0/20214.13.16.1 to 214.13.31.254214.13.31.2554,094
211214.13.32.0/20214.13.32.1 to 214.13.47.254214.13.47.2554,094
212214.13.48.0/20214.13.48.1 to 214.13.63.254214.13.63.2554,094
213214.13.64.0/20214.13.64.1 to 214.13.79.254214.13.79.2554,094
214214.13.80.0/20214.13.80.1 to 214.13.95.254214.13.95.2554,094
215214.13.96.0/20214.13.96.1 to 214.13.111.254214.13.111.2554,094
216214.13.112.0/20214.13.112.1 to 214.13.127.254214.13.127.2554,094
217214.13.128.0/20214.13.128.1 to 214.13.143.254214.13.143.2554,094
218214.13.144.0/20214.13.144.1 to 214.13.159.254214.13.159.2554,094
219214.13.160.0/20214.13.160.1 to 214.13.175.254214.13.175.2554,094
220214.13.176.0/20214.13.176.1 to 214.13.191.254214.13.191.2554,094
221214.13.192.0/20214.13.192.1 to 214.13.207.254214.13.207.2554,094
222214.13.208.0/20214.13.208.1 to 214.13.223.254214.13.223.2554,094
223214.13.224.0/20214.13.224.1 to 214.13.239.254214.13.239.2554,094
224214.13.240.0/20214.13.240.1 to 214.13.255.254214.13.255.2554,094
225214.14.0.0/20214.14.0.1 to 214.14.15.254214.14.15.2554,094
226214.14.16.0/20214.14.16.1 to 214.14.31.254214.14.31.2554,094
227214.14.32.0/20214.14.32.1 to 214.14.47.254214.14.47.2554,094
228214.14.48.0/20214.14.48.1 to 214.14.63.254214.14.63.2554,094
229214.14.64.0/20214.14.64.1 to 214.14.79.254214.14.79.2554,094
230214.14.80.0/20214.14.80.1 to 214.14.95.254214.14.95.2554,094
231214.14.96.0/20214.14.96.1 to 214.14.111.254214.14.111.2554,094
232214.14.112.0/20214.14.112.1 to 214.14.127.254214.14.127.2554,094
233214.14.128.0/20214.14.128.1 to 214.14.143.254214.14.143.2554,094
234214.14.144.0/20214.14.144.1 to 214.14.159.254214.14.159.2554,094
235214.14.160.0/20214.14.160.1 to 214.14.175.254214.14.175.2554,094
236214.14.176.0/20214.14.176.1 to 214.14.191.254214.14.191.2554,094
237214.14.192.0/20214.14.192.1 to 214.14.207.254214.14.207.2554,094
238214.14.208.0/20214.14.208.1 to 214.14.223.254214.14.223.2554,094
239214.14.224.0/20214.14.224.1 to 214.14.239.254214.14.239.2554,094
240214.14.240.0/20214.14.240.1 to 214.14.255.254214.14.255.2554,094
241214.15.0.0/20214.15.0.1 to 214.15.15.254214.15.15.2554,094
242214.15.16.0/20214.15.16.1 to 214.15.31.254214.15.31.2554,094
243214.15.32.0/20214.15.32.1 to 214.15.47.254214.15.47.2554,094
244214.15.48.0/20214.15.48.1 to 214.15.63.254214.15.63.2554,094
245214.15.64.0/20214.15.64.1 to 214.15.79.254214.15.79.2554,094
246214.15.80.0/20214.15.80.1 to 214.15.95.254214.15.95.2554,094
247214.15.96.0/20214.15.96.1 to 214.15.111.254214.15.111.2554,094
248214.15.112.0/20214.15.112.1 to 214.15.127.254214.15.127.2554,094
249214.15.128.0/20214.15.128.1 to 214.15.143.254214.15.143.2554,094
250214.15.144.0/20214.15.144.1 to 214.15.159.254214.15.159.2554,094
251214.15.160.0/20214.15.160.1 to 214.15.175.254214.15.175.2554,094
252214.15.176.0/20214.15.176.1 to 214.15.191.254214.15.191.2554,094
253214.15.192.0/20214.15.192.1 to 214.15.207.254214.15.207.2554,094
254214.15.208.0/20214.15.208.1 to 214.15.223.254214.15.223.2554,094
255214.15.224.0/20214.15.224.1 to 214.15.239.254214.15.239.2554,094
256214.15.240.0/20214.15.240.1 to 214.15.255.254214.15.255.2554,094

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.