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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.

Network140.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
140.0.0.0
Broadcast address
140.255.255.255
First usable
140.0.0.1
Last usable
140.255.255.254
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
B (default /16)
As numbers
Hex 8C000000 · Integer 2348810240 to 2365587455
Reverse DNS zone
140.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10001100..00000000.00000000.00000000140.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10001100..00000000.00000000.00000000140.0.0.0
Broadcast10001100..11111111.11111111.11111111140.255.255.255
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)

140.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1140.0.0.0/20140.0.0.1 to 140.0.15.254140.0.15.2554,094
2140.0.16.0/20140.0.16.1 to 140.0.31.254140.0.31.2554,094
3140.0.32.0/20140.0.32.1 to 140.0.47.254140.0.47.2554,094
4140.0.48.0/20140.0.48.1 to 140.0.63.254140.0.63.2554,094
5140.0.64.0/20140.0.64.1 to 140.0.79.254140.0.79.2554,094
6140.0.80.0/20140.0.80.1 to 140.0.95.254140.0.95.2554,094
7140.0.96.0/20140.0.96.1 to 140.0.111.254140.0.111.2554,094
8140.0.112.0/20140.0.112.1 to 140.0.127.254140.0.127.2554,094
9140.0.128.0/20140.0.128.1 to 140.0.143.254140.0.143.2554,094
10140.0.144.0/20140.0.144.1 to 140.0.159.254140.0.159.2554,094
11140.0.160.0/20140.0.160.1 to 140.0.175.254140.0.175.2554,094
12140.0.176.0/20140.0.176.1 to 140.0.191.254140.0.191.2554,094
13140.0.192.0/20140.0.192.1 to 140.0.207.254140.0.207.2554,094
14140.0.208.0/20140.0.208.1 to 140.0.223.254140.0.223.2554,094
15140.0.224.0/20140.0.224.1 to 140.0.239.254140.0.239.2554,094
16140.0.240.0/20140.0.240.1 to 140.0.255.254140.0.255.2554,094
17140.1.0.0/20140.1.0.1 to 140.1.15.254140.1.15.2554,094
18140.1.16.0/20140.1.16.1 to 140.1.31.254140.1.31.2554,094
19140.1.32.0/20140.1.32.1 to 140.1.47.254140.1.47.2554,094
20140.1.48.0/20140.1.48.1 to 140.1.63.254140.1.63.2554,094
21140.1.64.0/20140.1.64.1 to 140.1.79.254140.1.79.2554,094
22140.1.80.0/20140.1.80.1 to 140.1.95.254140.1.95.2554,094
23140.1.96.0/20140.1.96.1 to 140.1.111.254140.1.111.2554,094
24140.1.112.0/20140.1.112.1 to 140.1.127.254140.1.127.2554,094
25140.1.128.0/20140.1.128.1 to 140.1.143.254140.1.143.2554,094
26140.1.144.0/20140.1.144.1 to 140.1.159.254140.1.159.2554,094
27140.1.160.0/20140.1.160.1 to 140.1.175.254140.1.175.2554,094
28140.1.176.0/20140.1.176.1 to 140.1.191.254140.1.191.2554,094
29140.1.192.0/20140.1.192.1 to 140.1.207.254140.1.207.2554,094
30140.1.208.0/20140.1.208.1 to 140.1.223.254140.1.223.2554,094
31140.1.224.0/20140.1.224.1 to 140.1.239.254140.1.239.2554,094
32140.1.240.0/20140.1.240.1 to 140.1.255.254140.1.255.2554,094
33140.2.0.0/20140.2.0.1 to 140.2.15.254140.2.15.2554,094
34140.2.16.0/20140.2.16.1 to 140.2.31.254140.2.31.2554,094
35140.2.32.0/20140.2.32.1 to 140.2.47.254140.2.47.2554,094
36140.2.48.0/20140.2.48.1 to 140.2.63.254140.2.63.2554,094
37140.2.64.0/20140.2.64.1 to 140.2.79.254140.2.79.2554,094
38140.2.80.0/20140.2.80.1 to 140.2.95.254140.2.95.2554,094
39140.2.96.0/20140.2.96.1 to 140.2.111.254140.2.111.2554,094
40140.2.112.0/20140.2.112.1 to 140.2.127.254140.2.127.2554,094
41140.2.128.0/20140.2.128.1 to 140.2.143.254140.2.143.2554,094
42140.2.144.0/20140.2.144.1 to 140.2.159.254140.2.159.2554,094
43140.2.160.0/20140.2.160.1 to 140.2.175.254140.2.175.2554,094
44140.2.176.0/20140.2.176.1 to 140.2.191.254140.2.191.2554,094
45140.2.192.0/20140.2.192.1 to 140.2.207.254140.2.207.2554,094
46140.2.208.0/20140.2.208.1 to 140.2.223.254140.2.223.2554,094
47140.2.224.0/20140.2.224.1 to 140.2.239.254140.2.239.2554,094
48140.2.240.0/20140.2.240.1 to 140.2.255.254140.2.255.2554,094
49140.3.0.0/20140.3.0.1 to 140.3.15.254140.3.15.2554,094
50140.3.16.0/20140.3.16.1 to 140.3.31.254140.3.31.2554,094
51140.3.32.0/20140.3.32.1 to 140.3.47.254140.3.47.2554,094
52140.3.48.0/20140.3.48.1 to 140.3.63.254140.3.63.2554,094
53140.3.64.0/20140.3.64.1 to 140.3.79.254140.3.79.2554,094
54140.3.80.0/20140.3.80.1 to 140.3.95.254140.3.95.2554,094
55140.3.96.0/20140.3.96.1 to 140.3.111.254140.3.111.2554,094
56140.3.112.0/20140.3.112.1 to 140.3.127.254140.3.127.2554,094
57140.3.128.0/20140.3.128.1 to 140.3.143.254140.3.143.2554,094
58140.3.144.0/20140.3.144.1 to 140.3.159.254140.3.159.2554,094
59140.3.160.0/20140.3.160.1 to 140.3.175.254140.3.175.2554,094
60140.3.176.0/20140.3.176.1 to 140.3.191.254140.3.191.2554,094
61140.3.192.0/20140.3.192.1 to 140.3.207.254140.3.207.2554,094
62140.3.208.0/20140.3.208.1 to 140.3.223.254140.3.223.2554,094
63140.3.224.0/20140.3.224.1 to 140.3.239.254140.3.239.2554,094
64140.3.240.0/20140.3.240.1 to 140.3.255.254140.3.255.2554,094
65140.4.0.0/20140.4.0.1 to 140.4.15.254140.4.15.2554,094
66140.4.16.0/20140.4.16.1 to 140.4.31.254140.4.31.2554,094
67140.4.32.0/20140.4.32.1 to 140.4.47.254140.4.47.2554,094
68140.4.48.0/20140.4.48.1 to 140.4.63.254140.4.63.2554,094
69140.4.64.0/20140.4.64.1 to 140.4.79.254140.4.79.2554,094
70140.4.80.0/20140.4.80.1 to 140.4.95.254140.4.95.2554,094
71140.4.96.0/20140.4.96.1 to 140.4.111.254140.4.111.2554,094
72140.4.112.0/20140.4.112.1 to 140.4.127.254140.4.127.2554,094
73140.4.128.0/20140.4.128.1 to 140.4.143.254140.4.143.2554,094
74140.4.144.0/20140.4.144.1 to 140.4.159.254140.4.159.2554,094
75140.4.160.0/20140.4.160.1 to 140.4.175.254140.4.175.2554,094
76140.4.176.0/20140.4.176.1 to 140.4.191.254140.4.191.2554,094
77140.4.192.0/20140.4.192.1 to 140.4.207.254140.4.207.2554,094
78140.4.208.0/20140.4.208.1 to 140.4.223.254140.4.223.2554,094
79140.4.224.0/20140.4.224.1 to 140.4.239.254140.4.239.2554,094
80140.4.240.0/20140.4.240.1 to 140.4.255.254140.4.255.2554,094
81140.5.0.0/20140.5.0.1 to 140.5.15.254140.5.15.2554,094
82140.5.16.0/20140.5.16.1 to 140.5.31.254140.5.31.2554,094
83140.5.32.0/20140.5.32.1 to 140.5.47.254140.5.47.2554,094
84140.5.48.0/20140.5.48.1 to 140.5.63.254140.5.63.2554,094
85140.5.64.0/20140.5.64.1 to 140.5.79.254140.5.79.2554,094
86140.5.80.0/20140.5.80.1 to 140.5.95.254140.5.95.2554,094
87140.5.96.0/20140.5.96.1 to 140.5.111.254140.5.111.2554,094
88140.5.112.0/20140.5.112.1 to 140.5.127.254140.5.127.2554,094
89140.5.128.0/20140.5.128.1 to 140.5.143.254140.5.143.2554,094
90140.5.144.0/20140.5.144.1 to 140.5.159.254140.5.159.2554,094
91140.5.160.0/20140.5.160.1 to 140.5.175.254140.5.175.2554,094
92140.5.176.0/20140.5.176.1 to 140.5.191.254140.5.191.2554,094
93140.5.192.0/20140.5.192.1 to 140.5.207.254140.5.207.2554,094
94140.5.208.0/20140.5.208.1 to 140.5.223.254140.5.223.2554,094
95140.5.224.0/20140.5.224.1 to 140.5.239.254140.5.239.2554,094
96140.5.240.0/20140.5.240.1 to 140.5.255.254140.5.255.2554,094
97140.6.0.0/20140.6.0.1 to 140.6.15.254140.6.15.2554,094
98140.6.16.0/20140.6.16.1 to 140.6.31.254140.6.31.2554,094
99140.6.32.0/20140.6.32.1 to 140.6.47.254140.6.47.2554,094
100140.6.48.0/20140.6.48.1 to 140.6.63.254140.6.63.2554,094
101140.6.64.0/20140.6.64.1 to 140.6.79.254140.6.79.2554,094
102140.6.80.0/20140.6.80.1 to 140.6.95.254140.6.95.2554,094
103140.6.96.0/20140.6.96.1 to 140.6.111.254140.6.111.2554,094
104140.6.112.0/20140.6.112.1 to 140.6.127.254140.6.127.2554,094
105140.6.128.0/20140.6.128.1 to 140.6.143.254140.6.143.2554,094
106140.6.144.0/20140.6.144.1 to 140.6.159.254140.6.159.2554,094
107140.6.160.0/20140.6.160.1 to 140.6.175.254140.6.175.2554,094
108140.6.176.0/20140.6.176.1 to 140.6.191.254140.6.191.2554,094
109140.6.192.0/20140.6.192.1 to 140.6.207.254140.6.207.2554,094
110140.6.208.0/20140.6.208.1 to 140.6.223.254140.6.223.2554,094
111140.6.224.0/20140.6.224.1 to 140.6.239.254140.6.239.2554,094
112140.6.240.0/20140.6.240.1 to 140.6.255.254140.6.255.2554,094
113140.7.0.0/20140.7.0.1 to 140.7.15.254140.7.15.2554,094
114140.7.16.0/20140.7.16.1 to 140.7.31.254140.7.31.2554,094
115140.7.32.0/20140.7.32.1 to 140.7.47.254140.7.47.2554,094
116140.7.48.0/20140.7.48.1 to 140.7.63.254140.7.63.2554,094
117140.7.64.0/20140.7.64.1 to 140.7.79.254140.7.79.2554,094
118140.7.80.0/20140.7.80.1 to 140.7.95.254140.7.95.2554,094
119140.7.96.0/20140.7.96.1 to 140.7.111.254140.7.111.2554,094
120140.7.112.0/20140.7.112.1 to 140.7.127.254140.7.127.2554,094
121140.7.128.0/20140.7.128.1 to 140.7.143.254140.7.143.2554,094
122140.7.144.0/20140.7.144.1 to 140.7.159.254140.7.159.2554,094
123140.7.160.0/20140.7.160.1 to 140.7.175.254140.7.175.2554,094
124140.7.176.0/20140.7.176.1 to 140.7.191.254140.7.191.2554,094
125140.7.192.0/20140.7.192.1 to 140.7.207.254140.7.207.2554,094
126140.7.208.0/20140.7.208.1 to 140.7.223.254140.7.223.2554,094
127140.7.224.0/20140.7.224.1 to 140.7.239.254140.7.239.2554,094
128140.7.240.0/20140.7.240.1 to 140.7.255.254140.7.255.2554,094
129140.8.0.0/20140.8.0.1 to 140.8.15.254140.8.15.2554,094
130140.8.16.0/20140.8.16.1 to 140.8.31.254140.8.31.2554,094
131140.8.32.0/20140.8.32.1 to 140.8.47.254140.8.47.2554,094
132140.8.48.0/20140.8.48.1 to 140.8.63.254140.8.63.2554,094
133140.8.64.0/20140.8.64.1 to 140.8.79.254140.8.79.2554,094
134140.8.80.0/20140.8.80.1 to 140.8.95.254140.8.95.2554,094
135140.8.96.0/20140.8.96.1 to 140.8.111.254140.8.111.2554,094
136140.8.112.0/20140.8.112.1 to 140.8.127.254140.8.127.2554,094
137140.8.128.0/20140.8.128.1 to 140.8.143.254140.8.143.2554,094
138140.8.144.0/20140.8.144.1 to 140.8.159.254140.8.159.2554,094
139140.8.160.0/20140.8.160.1 to 140.8.175.254140.8.175.2554,094
140140.8.176.0/20140.8.176.1 to 140.8.191.254140.8.191.2554,094
141140.8.192.0/20140.8.192.1 to 140.8.207.254140.8.207.2554,094
142140.8.208.0/20140.8.208.1 to 140.8.223.254140.8.223.2554,094
143140.8.224.0/20140.8.224.1 to 140.8.239.254140.8.239.2554,094
144140.8.240.0/20140.8.240.1 to 140.8.255.254140.8.255.2554,094
145140.9.0.0/20140.9.0.1 to 140.9.15.254140.9.15.2554,094
146140.9.16.0/20140.9.16.1 to 140.9.31.254140.9.31.2554,094
147140.9.32.0/20140.9.32.1 to 140.9.47.254140.9.47.2554,094
148140.9.48.0/20140.9.48.1 to 140.9.63.254140.9.63.2554,094
149140.9.64.0/20140.9.64.1 to 140.9.79.254140.9.79.2554,094
150140.9.80.0/20140.9.80.1 to 140.9.95.254140.9.95.2554,094
151140.9.96.0/20140.9.96.1 to 140.9.111.254140.9.111.2554,094
152140.9.112.0/20140.9.112.1 to 140.9.127.254140.9.127.2554,094
153140.9.128.0/20140.9.128.1 to 140.9.143.254140.9.143.2554,094
154140.9.144.0/20140.9.144.1 to 140.9.159.254140.9.159.2554,094
155140.9.160.0/20140.9.160.1 to 140.9.175.254140.9.175.2554,094
156140.9.176.0/20140.9.176.1 to 140.9.191.254140.9.191.2554,094
157140.9.192.0/20140.9.192.1 to 140.9.207.254140.9.207.2554,094
158140.9.208.0/20140.9.208.1 to 140.9.223.254140.9.223.2554,094
159140.9.224.0/20140.9.224.1 to 140.9.239.254140.9.239.2554,094
160140.9.240.0/20140.9.240.1 to 140.9.255.254140.9.255.2554,094
161140.10.0.0/20140.10.0.1 to 140.10.15.254140.10.15.2554,094
162140.10.16.0/20140.10.16.1 to 140.10.31.254140.10.31.2554,094
163140.10.32.0/20140.10.32.1 to 140.10.47.254140.10.47.2554,094
164140.10.48.0/20140.10.48.1 to 140.10.63.254140.10.63.2554,094
165140.10.64.0/20140.10.64.1 to 140.10.79.254140.10.79.2554,094
166140.10.80.0/20140.10.80.1 to 140.10.95.254140.10.95.2554,094
167140.10.96.0/20140.10.96.1 to 140.10.111.254140.10.111.2554,094
168140.10.112.0/20140.10.112.1 to 140.10.127.254140.10.127.2554,094
169140.10.128.0/20140.10.128.1 to 140.10.143.254140.10.143.2554,094
170140.10.144.0/20140.10.144.1 to 140.10.159.254140.10.159.2554,094
171140.10.160.0/20140.10.160.1 to 140.10.175.254140.10.175.2554,094
172140.10.176.0/20140.10.176.1 to 140.10.191.254140.10.191.2554,094
173140.10.192.0/20140.10.192.1 to 140.10.207.254140.10.207.2554,094
174140.10.208.0/20140.10.208.1 to 140.10.223.254140.10.223.2554,094
175140.10.224.0/20140.10.224.1 to 140.10.239.254140.10.239.2554,094
176140.10.240.0/20140.10.240.1 to 140.10.255.254140.10.255.2554,094
177140.11.0.0/20140.11.0.1 to 140.11.15.254140.11.15.2554,094
178140.11.16.0/20140.11.16.1 to 140.11.31.254140.11.31.2554,094
179140.11.32.0/20140.11.32.1 to 140.11.47.254140.11.47.2554,094
180140.11.48.0/20140.11.48.1 to 140.11.63.254140.11.63.2554,094
181140.11.64.0/20140.11.64.1 to 140.11.79.254140.11.79.2554,094
182140.11.80.0/20140.11.80.1 to 140.11.95.254140.11.95.2554,094
183140.11.96.0/20140.11.96.1 to 140.11.111.254140.11.111.2554,094
184140.11.112.0/20140.11.112.1 to 140.11.127.254140.11.127.2554,094
185140.11.128.0/20140.11.128.1 to 140.11.143.254140.11.143.2554,094
186140.11.144.0/20140.11.144.1 to 140.11.159.254140.11.159.2554,094
187140.11.160.0/20140.11.160.1 to 140.11.175.254140.11.175.2554,094
188140.11.176.0/20140.11.176.1 to 140.11.191.254140.11.191.2554,094
189140.11.192.0/20140.11.192.1 to 140.11.207.254140.11.207.2554,094
190140.11.208.0/20140.11.208.1 to 140.11.223.254140.11.223.2554,094
191140.11.224.0/20140.11.224.1 to 140.11.239.254140.11.239.2554,094
192140.11.240.0/20140.11.240.1 to 140.11.255.254140.11.255.2554,094
193140.12.0.0/20140.12.0.1 to 140.12.15.254140.12.15.2554,094
194140.12.16.0/20140.12.16.1 to 140.12.31.254140.12.31.2554,094
195140.12.32.0/20140.12.32.1 to 140.12.47.254140.12.47.2554,094
196140.12.48.0/20140.12.48.1 to 140.12.63.254140.12.63.2554,094
197140.12.64.0/20140.12.64.1 to 140.12.79.254140.12.79.2554,094
198140.12.80.0/20140.12.80.1 to 140.12.95.254140.12.95.2554,094
199140.12.96.0/20140.12.96.1 to 140.12.111.254140.12.111.2554,094
200140.12.112.0/20140.12.112.1 to 140.12.127.254140.12.127.2554,094
201140.12.128.0/20140.12.128.1 to 140.12.143.254140.12.143.2554,094
202140.12.144.0/20140.12.144.1 to 140.12.159.254140.12.159.2554,094
203140.12.160.0/20140.12.160.1 to 140.12.175.254140.12.175.2554,094
204140.12.176.0/20140.12.176.1 to 140.12.191.254140.12.191.2554,094
205140.12.192.0/20140.12.192.1 to 140.12.207.254140.12.207.2554,094
206140.12.208.0/20140.12.208.1 to 140.12.223.254140.12.223.2554,094
207140.12.224.0/20140.12.224.1 to 140.12.239.254140.12.239.2554,094
208140.12.240.0/20140.12.240.1 to 140.12.255.254140.12.255.2554,094
209140.13.0.0/20140.13.0.1 to 140.13.15.254140.13.15.2554,094
210140.13.16.0/20140.13.16.1 to 140.13.31.254140.13.31.2554,094
211140.13.32.0/20140.13.32.1 to 140.13.47.254140.13.47.2554,094
212140.13.48.0/20140.13.48.1 to 140.13.63.254140.13.63.2554,094
213140.13.64.0/20140.13.64.1 to 140.13.79.254140.13.79.2554,094
214140.13.80.0/20140.13.80.1 to 140.13.95.254140.13.95.2554,094
215140.13.96.0/20140.13.96.1 to 140.13.111.254140.13.111.2554,094
216140.13.112.0/20140.13.112.1 to 140.13.127.254140.13.127.2554,094
217140.13.128.0/20140.13.128.1 to 140.13.143.254140.13.143.2554,094
218140.13.144.0/20140.13.144.1 to 140.13.159.254140.13.159.2554,094
219140.13.160.0/20140.13.160.1 to 140.13.175.254140.13.175.2554,094
220140.13.176.0/20140.13.176.1 to 140.13.191.254140.13.191.2554,094
221140.13.192.0/20140.13.192.1 to 140.13.207.254140.13.207.2554,094
222140.13.208.0/20140.13.208.1 to 140.13.223.254140.13.223.2554,094
223140.13.224.0/20140.13.224.1 to 140.13.239.254140.13.239.2554,094
224140.13.240.0/20140.13.240.1 to 140.13.255.254140.13.255.2554,094
225140.14.0.0/20140.14.0.1 to 140.14.15.254140.14.15.2554,094
226140.14.16.0/20140.14.16.1 to 140.14.31.254140.14.31.2554,094
227140.14.32.0/20140.14.32.1 to 140.14.47.254140.14.47.2554,094
228140.14.48.0/20140.14.48.1 to 140.14.63.254140.14.63.2554,094
229140.14.64.0/20140.14.64.1 to 140.14.79.254140.14.79.2554,094
230140.14.80.0/20140.14.80.1 to 140.14.95.254140.14.95.2554,094
231140.14.96.0/20140.14.96.1 to 140.14.111.254140.14.111.2554,094
232140.14.112.0/20140.14.112.1 to 140.14.127.254140.14.127.2554,094
233140.14.128.0/20140.14.128.1 to 140.14.143.254140.14.143.2554,094
234140.14.144.0/20140.14.144.1 to 140.14.159.254140.14.159.2554,094
235140.14.160.0/20140.14.160.1 to 140.14.175.254140.14.175.2554,094
236140.14.176.0/20140.14.176.1 to 140.14.191.254140.14.191.2554,094
237140.14.192.0/20140.14.192.1 to 140.14.207.254140.14.207.2554,094
238140.14.208.0/20140.14.208.1 to 140.14.223.254140.14.223.2554,094
239140.14.224.0/20140.14.224.1 to 140.14.239.254140.14.239.2554,094
240140.14.240.0/20140.14.240.1 to 140.14.255.254140.14.255.2554,094
241140.15.0.0/20140.15.0.1 to 140.15.15.254140.15.15.2554,094
242140.15.16.0/20140.15.16.1 to 140.15.31.254140.15.31.2554,094
243140.15.32.0/20140.15.32.1 to 140.15.47.254140.15.47.2554,094
244140.15.48.0/20140.15.48.1 to 140.15.63.254140.15.63.2554,094
245140.15.64.0/20140.15.64.1 to 140.15.79.254140.15.79.2554,094
246140.15.80.0/20140.15.80.1 to 140.15.95.254140.15.95.2554,094
247140.15.96.0/20140.15.96.1 to 140.15.111.254140.15.111.2554,094
248140.15.112.0/20140.15.112.1 to 140.15.127.254140.15.127.2554,094
249140.15.128.0/20140.15.128.1 to 140.15.143.254140.15.143.2554,094
250140.15.144.0/20140.15.144.1 to 140.15.159.254140.15.159.2554,094
251140.15.160.0/20140.15.160.1 to 140.15.175.254140.15.175.2554,094
252140.15.176.0/20140.15.176.1 to 140.15.191.254140.15.191.2554,094
253140.15.192.0/20140.15.192.1 to 140.15.207.254140.15.207.2554,094
254140.15.208.0/20140.15.208.1 to 140.15.223.254140.15.223.2554,094
255140.15.224.0/20140.15.224.1 to 140.15.239.254140.15.239.2554,094
256140.15.240.0/20140.15.240.1 to 140.15.255.254140.15.255.2554,094

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.