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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.

Network152.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
152.0.0.0
Broadcast address
152.255.255.255
First usable
152.0.0.1
Last usable
152.255.255.254
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 98000000 · Integer 2550136832 to 2566914047
Reverse DNS zone
152.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011000..00000000.00000000.00000000152.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10011000..00000000.00000000.00000000152.0.0.0
Broadcast10011000..11111111.11111111.11111111152.255.255.255
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)

152.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1152.0.0.0/20152.0.0.1 to 152.0.15.254152.0.15.2554,094
2152.0.16.0/20152.0.16.1 to 152.0.31.254152.0.31.2554,094
3152.0.32.0/20152.0.32.1 to 152.0.47.254152.0.47.2554,094
4152.0.48.0/20152.0.48.1 to 152.0.63.254152.0.63.2554,094
5152.0.64.0/20152.0.64.1 to 152.0.79.254152.0.79.2554,094
6152.0.80.0/20152.0.80.1 to 152.0.95.254152.0.95.2554,094
7152.0.96.0/20152.0.96.1 to 152.0.111.254152.0.111.2554,094
8152.0.112.0/20152.0.112.1 to 152.0.127.254152.0.127.2554,094
9152.0.128.0/20152.0.128.1 to 152.0.143.254152.0.143.2554,094
10152.0.144.0/20152.0.144.1 to 152.0.159.254152.0.159.2554,094
11152.0.160.0/20152.0.160.1 to 152.0.175.254152.0.175.2554,094
12152.0.176.0/20152.0.176.1 to 152.0.191.254152.0.191.2554,094
13152.0.192.0/20152.0.192.1 to 152.0.207.254152.0.207.2554,094
14152.0.208.0/20152.0.208.1 to 152.0.223.254152.0.223.2554,094
15152.0.224.0/20152.0.224.1 to 152.0.239.254152.0.239.2554,094
16152.0.240.0/20152.0.240.1 to 152.0.255.254152.0.255.2554,094
17152.1.0.0/20152.1.0.1 to 152.1.15.254152.1.15.2554,094
18152.1.16.0/20152.1.16.1 to 152.1.31.254152.1.31.2554,094
19152.1.32.0/20152.1.32.1 to 152.1.47.254152.1.47.2554,094
20152.1.48.0/20152.1.48.1 to 152.1.63.254152.1.63.2554,094
21152.1.64.0/20152.1.64.1 to 152.1.79.254152.1.79.2554,094
22152.1.80.0/20152.1.80.1 to 152.1.95.254152.1.95.2554,094
23152.1.96.0/20152.1.96.1 to 152.1.111.254152.1.111.2554,094
24152.1.112.0/20152.1.112.1 to 152.1.127.254152.1.127.2554,094
25152.1.128.0/20152.1.128.1 to 152.1.143.254152.1.143.2554,094
26152.1.144.0/20152.1.144.1 to 152.1.159.254152.1.159.2554,094
27152.1.160.0/20152.1.160.1 to 152.1.175.254152.1.175.2554,094
28152.1.176.0/20152.1.176.1 to 152.1.191.254152.1.191.2554,094
29152.1.192.0/20152.1.192.1 to 152.1.207.254152.1.207.2554,094
30152.1.208.0/20152.1.208.1 to 152.1.223.254152.1.223.2554,094
31152.1.224.0/20152.1.224.1 to 152.1.239.254152.1.239.2554,094
32152.1.240.0/20152.1.240.1 to 152.1.255.254152.1.255.2554,094
33152.2.0.0/20152.2.0.1 to 152.2.15.254152.2.15.2554,094
34152.2.16.0/20152.2.16.1 to 152.2.31.254152.2.31.2554,094
35152.2.32.0/20152.2.32.1 to 152.2.47.254152.2.47.2554,094
36152.2.48.0/20152.2.48.1 to 152.2.63.254152.2.63.2554,094
37152.2.64.0/20152.2.64.1 to 152.2.79.254152.2.79.2554,094
38152.2.80.0/20152.2.80.1 to 152.2.95.254152.2.95.2554,094
39152.2.96.0/20152.2.96.1 to 152.2.111.254152.2.111.2554,094
40152.2.112.0/20152.2.112.1 to 152.2.127.254152.2.127.2554,094
41152.2.128.0/20152.2.128.1 to 152.2.143.254152.2.143.2554,094
42152.2.144.0/20152.2.144.1 to 152.2.159.254152.2.159.2554,094
43152.2.160.0/20152.2.160.1 to 152.2.175.254152.2.175.2554,094
44152.2.176.0/20152.2.176.1 to 152.2.191.254152.2.191.2554,094
45152.2.192.0/20152.2.192.1 to 152.2.207.254152.2.207.2554,094
46152.2.208.0/20152.2.208.1 to 152.2.223.254152.2.223.2554,094
47152.2.224.0/20152.2.224.1 to 152.2.239.254152.2.239.2554,094
48152.2.240.0/20152.2.240.1 to 152.2.255.254152.2.255.2554,094
49152.3.0.0/20152.3.0.1 to 152.3.15.254152.3.15.2554,094
50152.3.16.0/20152.3.16.1 to 152.3.31.254152.3.31.2554,094
51152.3.32.0/20152.3.32.1 to 152.3.47.254152.3.47.2554,094
52152.3.48.0/20152.3.48.1 to 152.3.63.254152.3.63.2554,094
53152.3.64.0/20152.3.64.1 to 152.3.79.254152.3.79.2554,094
54152.3.80.0/20152.3.80.1 to 152.3.95.254152.3.95.2554,094
55152.3.96.0/20152.3.96.1 to 152.3.111.254152.3.111.2554,094
56152.3.112.0/20152.3.112.1 to 152.3.127.254152.3.127.2554,094
57152.3.128.0/20152.3.128.1 to 152.3.143.254152.3.143.2554,094
58152.3.144.0/20152.3.144.1 to 152.3.159.254152.3.159.2554,094
59152.3.160.0/20152.3.160.1 to 152.3.175.254152.3.175.2554,094
60152.3.176.0/20152.3.176.1 to 152.3.191.254152.3.191.2554,094
61152.3.192.0/20152.3.192.1 to 152.3.207.254152.3.207.2554,094
62152.3.208.0/20152.3.208.1 to 152.3.223.254152.3.223.2554,094
63152.3.224.0/20152.3.224.1 to 152.3.239.254152.3.239.2554,094
64152.3.240.0/20152.3.240.1 to 152.3.255.254152.3.255.2554,094
65152.4.0.0/20152.4.0.1 to 152.4.15.254152.4.15.2554,094
66152.4.16.0/20152.4.16.1 to 152.4.31.254152.4.31.2554,094
67152.4.32.0/20152.4.32.1 to 152.4.47.254152.4.47.2554,094
68152.4.48.0/20152.4.48.1 to 152.4.63.254152.4.63.2554,094
69152.4.64.0/20152.4.64.1 to 152.4.79.254152.4.79.2554,094
70152.4.80.0/20152.4.80.1 to 152.4.95.254152.4.95.2554,094
71152.4.96.0/20152.4.96.1 to 152.4.111.254152.4.111.2554,094
72152.4.112.0/20152.4.112.1 to 152.4.127.254152.4.127.2554,094
73152.4.128.0/20152.4.128.1 to 152.4.143.254152.4.143.2554,094
74152.4.144.0/20152.4.144.1 to 152.4.159.254152.4.159.2554,094
75152.4.160.0/20152.4.160.1 to 152.4.175.254152.4.175.2554,094
76152.4.176.0/20152.4.176.1 to 152.4.191.254152.4.191.2554,094
77152.4.192.0/20152.4.192.1 to 152.4.207.254152.4.207.2554,094
78152.4.208.0/20152.4.208.1 to 152.4.223.254152.4.223.2554,094
79152.4.224.0/20152.4.224.1 to 152.4.239.254152.4.239.2554,094
80152.4.240.0/20152.4.240.1 to 152.4.255.254152.4.255.2554,094
81152.5.0.0/20152.5.0.1 to 152.5.15.254152.5.15.2554,094
82152.5.16.0/20152.5.16.1 to 152.5.31.254152.5.31.2554,094
83152.5.32.0/20152.5.32.1 to 152.5.47.254152.5.47.2554,094
84152.5.48.0/20152.5.48.1 to 152.5.63.254152.5.63.2554,094
85152.5.64.0/20152.5.64.1 to 152.5.79.254152.5.79.2554,094
86152.5.80.0/20152.5.80.1 to 152.5.95.254152.5.95.2554,094
87152.5.96.0/20152.5.96.1 to 152.5.111.254152.5.111.2554,094
88152.5.112.0/20152.5.112.1 to 152.5.127.254152.5.127.2554,094
89152.5.128.0/20152.5.128.1 to 152.5.143.254152.5.143.2554,094
90152.5.144.0/20152.5.144.1 to 152.5.159.254152.5.159.2554,094
91152.5.160.0/20152.5.160.1 to 152.5.175.254152.5.175.2554,094
92152.5.176.0/20152.5.176.1 to 152.5.191.254152.5.191.2554,094
93152.5.192.0/20152.5.192.1 to 152.5.207.254152.5.207.2554,094
94152.5.208.0/20152.5.208.1 to 152.5.223.254152.5.223.2554,094
95152.5.224.0/20152.5.224.1 to 152.5.239.254152.5.239.2554,094
96152.5.240.0/20152.5.240.1 to 152.5.255.254152.5.255.2554,094
97152.6.0.0/20152.6.0.1 to 152.6.15.254152.6.15.2554,094
98152.6.16.0/20152.6.16.1 to 152.6.31.254152.6.31.2554,094
99152.6.32.0/20152.6.32.1 to 152.6.47.254152.6.47.2554,094
100152.6.48.0/20152.6.48.1 to 152.6.63.254152.6.63.2554,094
101152.6.64.0/20152.6.64.1 to 152.6.79.254152.6.79.2554,094
102152.6.80.0/20152.6.80.1 to 152.6.95.254152.6.95.2554,094
103152.6.96.0/20152.6.96.1 to 152.6.111.254152.6.111.2554,094
104152.6.112.0/20152.6.112.1 to 152.6.127.254152.6.127.2554,094
105152.6.128.0/20152.6.128.1 to 152.6.143.254152.6.143.2554,094
106152.6.144.0/20152.6.144.1 to 152.6.159.254152.6.159.2554,094
107152.6.160.0/20152.6.160.1 to 152.6.175.254152.6.175.2554,094
108152.6.176.0/20152.6.176.1 to 152.6.191.254152.6.191.2554,094
109152.6.192.0/20152.6.192.1 to 152.6.207.254152.6.207.2554,094
110152.6.208.0/20152.6.208.1 to 152.6.223.254152.6.223.2554,094
111152.6.224.0/20152.6.224.1 to 152.6.239.254152.6.239.2554,094
112152.6.240.0/20152.6.240.1 to 152.6.255.254152.6.255.2554,094
113152.7.0.0/20152.7.0.1 to 152.7.15.254152.7.15.2554,094
114152.7.16.0/20152.7.16.1 to 152.7.31.254152.7.31.2554,094
115152.7.32.0/20152.7.32.1 to 152.7.47.254152.7.47.2554,094
116152.7.48.0/20152.7.48.1 to 152.7.63.254152.7.63.2554,094
117152.7.64.0/20152.7.64.1 to 152.7.79.254152.7.79.2554,094
118152.7.80.0/20152.7.80.1 to 152.7.95.254152.7.95.2554,094
119152.7.96.0/20152.7.96.1 to 152.7.111.254152.7.111.2554,094
120152.7.112.0/20152.7.112.1 to 152.7.127.254152.7.127.2554,094
121152.7.128.0/20152.7.128.1 to 152.7.143.254152.7.143.2554,094
122152.7.144.0/20152.7.144.1 to 152.7.159.254152.7.159.2554,094
123152.7.160.0/20152.7.160.1 to 152.7.175.254152.7.175.2554,094
124152.7.176.0/20152.7.176.1 to 152.7.191.254152.7.191.2554,094
125152.7.192.0/20152.7.192.1 to 152.7.207.254152.7.207.2554,094
126152.7.208.0/20152.7.208.1 to 152.7.223.254152.7.223.2554,094
127152.7.224.0/20152.7.224.1 to 152.7.239.254152.7.239.2554,094
128152.7.240.0/20152.7.240.1 to 152.7.255.254152.7.255.2554,094
129152.8.0.0/20152.8.0.1 to 152.8.15.254152.8.15.2554,094
130152.8.16.0/20152.8.16.1 to 152.8.31.254152.8.31.2554,094
131152.8.32.0/20152.8.32.1 to 152.8.47.254152.8.47.2554,094
132152.8.48.0/20152.8.48.1 to 152.8.63.254152.8.63.2554,094
133152.8.64.0/20152.8.64.1 to 152.8.79.254152.8.79.2554,094
134152.8.80.0/20152.8.80.1 to 152.8.95.254152.8.95.2554,094
135152.8.96.0/20152.8.96.1 to 152.8.111.254152.8.111.2554,094
136152.8.112.0/20152.8.112.1 to 152.8.127.254152.8.127.2554,094
137152.8.128.0/20152.8.128.1 to 152.8.143.254152.8.143.2554,094
138152.8.144.0/20152.8.144.1 to 152.8.159.254152.8.159.2554,094
139152.8.160.0/20152.8.160.1 to 152.8.175.254152.8.175.2554,094
140152.8.176.0/20152.8.176.1 to 152.8.191.254152.8.191.2554,094
141152.8.192.0/20152.8.192.1 to 152.8.207.254152.8.207.2554,094
142152.8.208.0/20152.8.208.1 to 152.8.223.254152.8.223.2554,094
143152.8.224.0/20152.8.224.1 to 152.8.239.254152.8.239.2554,094
144152.8.240.0/20152.8.240.1 to 152.8.255.254152.8.255.2554,094
145152.9.0.0/20152.9.0.1 to 152.9.15.254152.9.15.2554,094
146152.9.16.0/20152.9.16.1 to 152.9.31.254152.9.31.2554,094
147152.9.32.0/20152.9.32.1 to 152.9.47.254152.9.47.2554,094
148152.9.48.0/20152.9.48.1 to 152.9.63.254152.9.63.2554,094
149152.9.64.0/20152.9.64.1 to 152.9.79.254152.9.79.2554,094
150152.9.80.0/20152.9.80.1 to 152.9.95.254152.9.95.2554,094
151152.9.96.0/20152.9.96.1 to 152.9.111.254152.9.111.2554,094
152152.9.112.0/20152.9.112.1 to 152.9.127.254152.9.127.2554,094
153152.9.128.0/20152.9.128.1 to 152.9.143.254152.9.143.2554,094
154152.9.144.0/20152.9.144.1 to 152.9.159.254152.9.159.2554,094
155152.9.160.0/20152.9.160.1 to 152.9.175.254152.9.175.2554,094
156152.9.176.0/20152.9.176.1 to 152.9.191.254152.9.191.2554,094
157152.9.192.0/20152.9.192.1 to 152.9.207.254152.9.207.2554,094
158152.9.208.0/20152.9.208.1 to 152.9.223.254152.9.223.2554,094
159152.9.224.0/20152.9.224.1 to 152.9.239.254152.9.239.2554,094
160152.9.240.0/20152.9.240.1 to 152.9.255.254152.9.255.2554,094
161152.10.0.0/20152.10.0.1 to 152.10.15.254152.10.15.2554,094
162152.10.16.0/20152.10.16.1 to 152.10.31.254152.10.31.2554,094
163152.10.32.0/20152.10.32.1 to 152.10.47.254152.10.47.2554,094
164152.10.48.0/20152.10.48.1 to 152.10.63.254152.10.63.2554,094
165152.10.64.0/20152.10.64.1 to 152.10.79.254152.10.79.2554,094
166152.10.80.0/20152.10.80.1 to 152.10.95.254152.10.95.2554,094
167152.10.96.0/20152.10.96.1 to 152.10.111.254152.10.111.2554,094
168152.10.112.0/20152.10.112.1 to 152.10.127.254152.10.127.2554,094
169152.10.128.0/20152.10.128.1 to 152.10.143.254152.10.143.2554,094
170152.10.144.0/20152.10.144.1 to 152.10.159.254152.10.159.2554,094
171152.10.160.0/20152.10.160.1 to 152.10.175.254152.10.175.2554,094
172152.10.176.0/20152.10.176.1 to 152.10.191.254152.10.191.2554,094
173152.10.192.0/20152.10.192.1 to 152.10.207.254152.10.207.2554,094
174152.10.208.0/20152.10.208.1 to 152.10.223.254152.10.223.2554,094
175152.10.224.0/20152.10.224.1 to 152.10.239.254152.10.239.2554,094
176152.10.240.0/20152.10.240.1 to 152.10.255.254152.10.255.2554,094
177152.11.0.0/20152.11.0.1 to 152.11.15.254152.11.15.2554,094
178152.11.16.0/20152.11.16.1 to 152.11.31.254152.11.31.2554,094
179152.11.32.0/20152.11.32.1 to 152.11.47.254152.11.47.2554,094
180152.11.48.0/20152.11.48.1 to 152.11.63.254152.11.63.2554,094
181152.11.64.0/20152.11.64.1 to 152.11.79.254152.11.79.2554,094
182152.11.80.0/20152.11.80.1 to 152.11.95.254152.11.95.2554,094
183152.11.96.0/20152.11.96.1 to 152.11.111.254152.11.111.2554,094
184152.11.112.0/20152.11.112.1 to 152.11.127.254152.11.127.2554,094
185152.11.128.0/20152.11.128.1 to 152.11.143.254152.11.143.2554,094
186152.11.144.0/20152.11.144.1 to 152.11.159.254152.11.159.2554,094
187152.11.160.0/20152.11.160.1 to 152.11.175.254152.11.175.2554,094
188152.11.176.0/20152.11.176.1 to 152.11.191.254152.11.191.2554,094
189152.11.192.0/20152.11.192.1 to 152.11.207.254152.11.207.2554,094
190152.11.208.0/20152.11.208.1 to 152.11.223.254152.11.223.2554,094
191152.11.224.0/20152.11.224.1 to 152.11.239.254152.11.239.2554,094
192152.11.240.0/20152.11.240.1 to 152.11.255.254152.11.255.2554,094
193152.12.0.0/20152.12.0.1 to 152.12.15.254152.12.15.2554,094
194152.12.16.0/20152.12.16.1 to 152.12.31.254152.12.31.2554,094
195152.12.32.0/20152.12.32.1 to 152.12.47.254152.12.47.2554,094
196152.12.48.0/20152.12.48.1 to 152.12.63.254152.12.63.2554,094
197152.12.64.0/20152.12.64.1 to 152.12.79.254152.12.79.2554,094
198152.12.80.0/20152.12.80.1 to 152.12.95.254152.12.95.2554,094
199152.12.96.0/20152.12.96.1 to 152.12.111.254152.12.111.2554,094
200152.12.112.0/20152.12.112.1 to 152.12.127.254152.12.127.2554,094
201152.12.128.0/20152.12.128.1 to 152.12.143.254152.12.143.2554,094
202152.12.144.0/20152.12.144.1 to 152.12.159.254152.12.159.2554,094
203152.12.160.0/20152.12.160.1 to 152.12.175.254152.12.175.2554,094
204152.12.176.0/20152.12.176.1 to 152.12.191.254152.12.191.2554,094
205152.12.192.0/20152.12.192.1 to 152.12.207.254152.12.207.2554,094
206152.12.208.0/20152.12.208.1 to 152.12.223.254152.12.223.2554,094
207152.12.224.0/20152.12.224.1 to 152.12.239.254152.12.239.2554,094
208152.12.240.0/20152.12.240.1 to 152.12.255.254152.12.255.2554,094
209152.13.0.0/20152.13.0.1 to 152.13.15.254152.13.15.2554,094
210152.13.16.0/20152.13.16.1 to 152.13.31.254152.13.31.2554,094
211152.13.32.0/20152.13.32.1 to 152.13.47.254152.13.47.2554,094
212152.13.48.0/20152.13.48.1 to 152.13.63.254152.13.63.2554,094
213152.13.64.0/20152.13.64.1 to 152.13.79.254152.13.79.2554,094
214152.13.80.0/20152.13.80.1 to 152.13.95.254152.13.95.2554,094
215152.13.96.0/20152.13.96.1 to 152.13.111.254152.13.111.2554,094
216152.13.112.0/20152.13.112.1 to 152.13.127.254152.13.127.2554,094
217152.13.128.0/20152.13.128.1 to 152.13.143.254152.13.143.2554,094
218152.13.144.0/20152.13.144.1 to 152.13.159.254152.13.159.2554,094
219152.13.160.0/20152.13.160.1 to 152.13.175.254152.13.175.2554,094
220152.13.176.0/20152.13.176.1 to 152.13.191.254152.13.191.2554,094
221152.13.192.0/20152.13.192.1 to 152.13.207.254152.13.207.2554,094
222152.13.208.0/20152.13.208.1 to 152.13.223.254152.13.223.2554,094
223152.13.224.0/20152.13.224.1 to 152.13.239.254152.13.239.2554,094
224152.13.240.0/20152.13.240.1 to 152.13.255.254152.13.255.2554,094
225152.14.0.0/20152.14.0.1 to 152.14.15.254152.14.15.2554,094
226152.14.16.0/20152.14.16.1 to 152.14.31.254152.14.31.2554,094
227152.14.32.0/20152.14.32.1 to 152.14.47.254152.14.47.2554,094
228152.14.48.0/20152.14.48.1 to 152.14.63.254152.14.63.2554,094
229152.14.64.0/20152.14.64.1 to 152.14.79.254152.14.79.2554,094
230152.14.80.0/20152.14.80.1 to 152.14.95.254152.14.95.2554,094
231152.14.96.0/20152.14.96.1 to 152.14.111.254152.14.111.2554,094
232152.14.112.0/20152.14.112.1 to 152.14.127.254152.14.127.2554,094
233152.14.128.0/20152.14.128.1 to 152.14.143.254152.14.143.2554,094
234152.14.144.0/20152.14.144.1 to 152.14.159.254152.14.159.2554,094
235152.14.160.0/20152.14.160.1 to 152.14.175.254152.14.175.2554,094
236152.14.176.0/20152.14.176.1 to 152.14.191.254152.14.191.2554,094
237152.14.192.0/20152.14.192.1 to 152.14.207.254152.14.207.2554,094
238152.14.208.0/20152.14.208.1 to 152.14.223.254152.14.223.2554,094
239152.14.224.0/20152.14.224.1 to 152.14.239.254152.14.239.2554,094
240152.14.240.0/20152.14.240.1 to 152.14.255.254152.14.255.2554,094
241152.15.0.0/20152.15.0.1 to 152.15.15.254152.15.15.2554,094
242152.15.16.0/20152.15.16.1 to 152.15.31.254152.15.31.2554,094
243152.15.32.0/20152.15.32.1 to 152.15.47.254152.15.47.2554,094
244152.15.48.0/20152.15.48.1 to 152.15.63.254152.15.63.2554,094
245152.15.64.0/20152.15.64.1 to 152.15.79.254152.15.79.2554,094
246152.15.80.0/20152.15.80.1 to 152.15.95.254152.15.95.2554,094
247152.15.96.0/20152.15.96.1 to 152.15.111.254152.15.111.2554,094
248152.15.112.0/20152.15.112.1 to 152.15.127.254152.15.127.2554,094
249152.15.128.0/20152.15.128.1 to 152.15.143.254152.15.143.2554,094
250152.15.144.0/20152.15.144.1 to 152.15.159.254152.15.159.2554,094
251152.15.160.0/20152.15.160.1 to 152.15.175.254152.15.175.2554,094
252152.15.176.0/20152.15.176.1 to 152.15.191.254152.15.191.2554,094
253152.15.192.0/20152.15.192.1 to 152.15.207.254152.15.207.2554,094
254152.15.208.0/20152.15.208.1 to 152.15.223.254152.15.223.2554,094
255152.15.224.0/20152.15.224.1 to 152.15.239.254152.15.239.2554,094
256152.15.240.0/20152.15.240.1 to 152.15.255.254152.15.255.2554,094

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.