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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.

Network158.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
158.0.0.0
Broadcast address
158.255.255.255
First usable
158.0.0.1
Last usable
158.255.255.254
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 9E000000 · Integer 2650800128 to 2667577343
Reverse DNS zone
158.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011110..00000000.00000000.00000000158.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10011110..00000000.00000000.00000000158.0.0.0
Broadcast10011110..11111111.11111111.11111111158.255.255.255
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)

158.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1158.0.0.0/20158.0.0.1 to 158.0.15.254158.0.15.2554,094
2158.0.16.0/20158.0.16.1 to 158.0.31.254158.0.31.2554,094
3158.0.32.0/20158.0.32.1 to 158.0.47.254158.0.47.2554,094
4158.0.48.0/20158.0.48.1 to 158.0.63.254158.0.63.2554,094
5158.0.64.0/20158.0.64.1 to 158.0.79.254158.0.79.2554,094
6158.0.80.0/20158.0.80.1 to 158.0.95.254158.0.95.2554,094
7158.0.96.0/20158.0.96.1 to 158.0.111.254158.0.111.2554,094
8158.0.112.0/20158.0.112.1 to 158.0.127.254158.0.127.2554,094
9158.0.128.0/20158.0.128.1 to 158.0.143.254158.0.143.2554,094
10158.0.144.0/20158.0.144.1 to 158.0.159.254158.0.159.2554,094
11158.0.160.0/20158.0.160.1 to 158.0.175.254158.0.175.2554,094
12158.0.176.0/20158.0.176.1 to 158.0.191.254158.0.191.2554,094
13158.0.192.0/20158.0.192.1 to 158.0.207.254158.0.207.2554,094
14158.0.208.0/20158.0.208.1 to 158.0.223.254158.0.223.2554,094
15158.0.224.0/20158.0.224.1 to 158.0.239.254158.0.239.2554,094
16158.0.240.0/20158.0.240.1 to 158.0.255.254158.0.255.2554,094
17158.1.0.0/20158.1.0.1 to 158.1.15.254158.1.15.2554,094
18158.1.16.0/20158.1.16.1 to 158.1.31.254158.1.31.2554,094
19158.1.32.0/20158.1.32.1 to 158.1.47.254158.1.47.2554,094
20158.1.48.0/20158.1.48.1 to 158.1.63.254158.1.63.2554,094
21158.1.64.0/20158.1.64.1 to 158.1.79.254158.1.79.2554,094
22158.1.80.0/20158.1.80.1 to 158.1.95.254158.1.95.2554,094
23158.1.96.0/20158.1.96.1 to 158.1.111.254158.1.111.2554,094
24158.1.112.0/20158.1.112.1 to 158.1.127.254158.1.127.2554,094
25158.1.128.0/20158.1.128.1 to 158.1.143.254158.1.143.2554,094
26158.1.144.0/20158.1.144.1 to 158.1.159.254158.1.159.2554,094
27158.1.160.0/20158.1.160.1 to 158.1.175.254158.1.175.2554,094
28158.1.176.0/20158.1.176.1 to 158.1.191.254158.1.191.2554,094
29158.1.192.0/20158.1.192.1 to 158.1.207.254158.1.207.2554,094
30158.1.208.0/20158.1.208.1 to 158.1.223.254158.1.223.2554,094
31158.1.224.0/20158.1.224.1 to 158.1.239.254158.1.239.2554,094
32158.1.240.0/20158.1.240.1 to 158.1.255.254158.1.255.2554,094
33158.2.0.0/20158.2.0.1 to 158.2.15.254158.2.15.2554,094
34158.2.16.0/20158.2.16.1 to 158.2.31.254158.2.31.2554,094
35158.2.32.0/20158.2.32.1 to 158.2.47.254158.2.47.2554,094
36158.2.48.0/20158.2.48.1 to 158.2.63.254158.2.63.2554,094
37158.2.64.0/20158.2.64.1 to 158.2.79.254158.2.79.2554,094
38158.2.80.0/20158.2.80.1 to 158.2.95.254158.2.95.2554,094
39158.2.96.0/20158.2.96.1 to 158.2.111.254158.2.111.2554,094
40158.2.112.0/20158.2.112.1 to 158.2.127.254158.2.127.2554,094
41158.2.128.0/20158.2.128.1 to 158.2.143.254158.2.143.2554,094
42158.2.144.0/20158.2.144.1 to 158.2.159.254158.2.159.2554,094
43158.2.160.0/20158.2.160.1 to 158.2.175.254158.2.175.2554,094
44158.2.176.0/20158.2.176.1 to 158.2.191.254158.2.191.2554,094
45158.2.192.0/20158.2.192.1 to 158.2.207.254158.2.207.2554,094
46158.2.208.0/20158.2.208.1 to 158.2.223.254158.2.223.2554,094
47158.2.224.0/20158.2.224.1 to 158.2.239.254158.2.239.2554,094
48158.2.240.0/20158.2.240.1 to 158.2.255.254158.2.255.2554,094
49158.3.0.0/20158.3.0.1 to 158.3.15.254158.3.15.2554,094
50158.3.16.0/20158.3.16.1 to 158.3.31.254158.3.31.2554,094
51158.3.32.0/20158.3.32.1 to 158.3.47.254158.3.47.2554,094
52158.3.48.0/20158.3.48.1 to 158.3.63.254158.3.63.2554,094
53158.3.64.0/20158.3.64.1 to 158.3.79.254158.3.79.2554,094
54158.3.80.0/20158.3.80.1 to 158.3.95.254158.3.95.2554,094
55158.3.96.0/20158.3.96.1 to 158.3.111.254158.3.111.2554,094
56158.3.112.0/20158.3.112.1 to 158.3.127.254158.3.127.2554,094
57158.3.128.0/20158.3.128.1 to 158.3.143.254158.3.143.2554,094
58158.3.144.0/20158.3.144.1 to 158.3.159.254158.3.159.2554,094
59158.3.160.0/20158.3.160.1 to 158.3.175.254158.3.175.2554,094
60158.3.176.0/20158.3.176.1 to 158.3.191.254158.3.191.2554,094
61158.3.192.0/20158.3.192.1 to 158.3.207.254158.3.207.2554,094
62158.3.208.0/20158.3.208.1 to 158.3.223.254158.3.223.2554,094
63158.3.224.0/20158.3.224.1 to 158.3.239.254158.3.239.2554,094
64158.3.240.0/20158.3.240.1 to 158.3.255.254158.3.255.2554,094
65158.4.0.0/20158.4.0.1 to 158.4.15.254158.4.15.2554,094
66158.4.16.0/20158.4.16.1 to 158.4.31.254158.4.31.2554,094
67158.4.32.0/20158.4.32.1 to 158.4.47.254158.4.47.2554,094
68158.4.48.0/20158.4.48.1 to 158.4.63.254158.4.63.2554,094
69158.4.64.0/20158.4.64.1 to 158.4.79.254158.4.79.2554,094
70158.4.80.0/20158.4.80.1 to 158.4.95.254158.4.95.2554,094
71158.4.96.0/20158.4.96.1 to 158.4.111.254158.4.111.2554,094
72158.4.112.0/20158.4.112.1 to 158.4.127.254158.4.127.2554,094
73158.4.128.0/20158.4.128.1 to 158.4.143.254158.4.143.2554,094
74158.4.144.0/20158.4.144.1 to 158.4.159.254158.4.159.2554,094
75158.4.160.0/20158.4.160.1 to 158.4.175.254158.4.175.2554,094
76158.4.176.0/20158.4.176.1 to 158.4.191.254158.4.191.2554,094
77158.4.192.0/20158.4.192.1 to 158.4.207.254158.4.207.2554,094
78158.4.208.0/20158.4.208.1 to 158.4.223.254158.4.223.2554,094
79158.4.224.0/20158.4.224.1 to 158.4.239.254158.4.239.2554,094
80158.4.240.0/20158.4.240.1 to 158.4.255.254158.4.255.2554,094
81158.5.0.0/20158.5.0.1 to 158.5.15.254158.5.15.2554,094
82158.5.16.0/20158.5.16.1 to 158.5.31.254158.5.31.2554,094
83158.5.32.0/20158.5.32.1 to 158.5.47.254158.5.47.2554,094
84158.5.48.0/20158.5.48.1 to 158.5.63.254158.5.63.2554,094
85158.5.64.0/20158.5.64.1 to 158.5.79.254158.5.79.2554,094
86158.5.80.0/20158.5.80.1 to 158.5.95.254158.5.95.2554,094
87158.5.96.0/20158.5.96.1 to 158.5.111.254158.5.111.2554,094
88158.5.112.0/20158.5.112.1 to 158.5.127.254158.5.127.2554,094
89158.5.128.0/20158.5.128.1 to 158.5.143.254158.5.143.2554,094
90158.5.144.0/20158.5.144.1 to 158.5.159.254158.5.159.2554,094
91158.5.160.0/20158.5.160.1 to 158.5.175.254158.5.175.2554,094
92158.5.176.0/20158.5.176.1 to 158.5.191.254158.5.191.2554,094
93158.5.192.0/20158.5.192.1 to 158.5.207.254158.5.207.2554,094
94158.5.208.0/20158.5.208.1 to 158.5.223.254158.5.223.2554,094
95158.5.224.0/20158.5.224.1 to 158.5.239.254158.5.239.2554,094
96158.5.240.0/20158.5.240.1 to 158.5.255.254158.5.255.2554,094
97158.6.0.0/20158.6.0.1 to 158.6.15.254158.6.15.2554,094
98158.6.16.0/20158.6.16.1 to 158.6.31.254158.6.31.2554,094
99158.6.32.0/20158.6.32.1 to 158.6.47.254158.6.47.2554,094
100158.6.48.0/20158.6.48.1 to 158.6.63.254158.6.63.2554,094
101158.6.64.0/20158.6.64.1 to 158.6.79.254158.6.79.2554,094
102158.6.80.0/20158.6.80.1 to 158.6.95.254158.6.95.2554,094
103158.6.96.0/20158.6.96.1 to 158.6.111.254158.6.111.2554,094
104158.6.112.0/20158.6.112.1 to 158.6.127.254158.6.127.2554,094
105158.6.128.0/20158.6.128.1 to 158.6.143.254158.6.143.2554,094
106158.6.144.0/20158.6.144.1 to 158.6.159.254158.6.159.2554,094
107158.6.160.0/20158.6.160.1 to 158.6.175.254158.6.175.2554,094
108158.6.176.0/20158.6.176.1 to 158.6.191.254158.6.191.2554,094
109158.6.192.0/20158.6.192.1 to 158.6.207.254158.6.207.2554,094
110158.6.208.0/20158.6.208.1 to 158.6.223.254158.6.223.2554,094
111158.6.224.0/20158.6.224.1 to 158.6.239.254158.6.239.2554,094
112158.6.240.0/20158.6.240.1 to 158.6.255.254158.6.255.2554,094
113158.7.0.0/20158.7.0.1 to 158.7.15.254158.7.15.2554,094
114158.7.16.0/20158.7.16.1 to 158.7.31.254158.7.31.2554,094
115158.7.32.0/20158.7.32.1 to 158.7.47.254158.7.47.2554,094
116158.7.48.0/20158.7.48.1 to 158.7.63.254158.7.63.2554,094
117158.7.64.0/20158.7.64.1 to 158.7.79.254158.7.79.2554,094
118158.7.80.0/20158.7.80.1 to 158.7.95.254158.7.95.2554,094
119158.7.96.0/20158.7.96.1 to 158.7.111.254158.7.111.2554,094
120158.7.112.0/20158.7.112.1 to 158.7.127.254158.7.127.2554,094
121158.7.128.0/20158.7.128.1 to 158.7.143.254158.7.143.2554,094
122158.7.144.0/20158.7.144.1 to 158.7.159.254158.7.159.2554,094
123158.7.160.0/20158.7.160.1 to 158.7.175.254158.7.175.2554,094
124158.7.176.0/20158.7.176.1 to 158.7.191.254158.7.191.2554,094
125158.7.192.0/20158.7.192.1 to 158.7.207.254158.7.207.2554,094
126158.7.208.0/20158.7.208.1 to 158.7.223.254158.7.223.2554,094
127158.7.224.0/20158.7.224.1 to 158.7.239.254158.7.239.2554,094
128158.7.240.0/20158.7.240.1 to 158.7.255.254158.7.255.2554,094
129158.8.0.0/20158.8.0.1 to 158.8.15.254158.8.15.2554,094
130158.8.16.0/20158.8.16.1 to 158.8.31.254158.8.31.2554,094
131158.8.32.0/20158.8.32.1 to 158.8.47.254158.8.47.2554,094
132158.8.48.0/20158.8.48.1 to 158.8.63.254158.8.63.2554,094
133158.8.64.0/20158.8.64.1 to 158.8.79.254158.8.79.2554,094
134158.8.80.0/20158.8.80.1 to 158.8.95.254158.8.95.2554,094
135158.8.96.0/20158.8.96.1 to 158.8.111.254158.8.111.2554,094
136158.8.112.0/20158.8.112.1 to 158.8.127.254158.8.127.2554,094
137158.8.128.0/20158.8.128.1 to 158.8.143.254158.8.143.2554,094
138158.8.144.0/20158.8.144.1 to 158.8.159.254158.8.159.2554,094
139158.8.160.0/20158.8.160.1 to 158.8.175.254158.8.175.2554,094
140158.8.176.0/20158.8.176.1 to 158.8.191.254158.8.191.2554,094
141158.8.192.0/20158.8.192.1 to 158.8.207.254158.8.207.2554,094
142158.8.208.0/20158.8.208.1 to 158.8.223.254158.8.223.2554,094
143158.8.224.0/20158.8.224.1 to 158.8.239.254158.8.239.2554,094
144158.8.240.0/20158.8.240.1 to 158.8.255.254158.8.255.2554,094
145158.9.0.0/20158.9.0.1 to 158.9.15.254158.9.15.2554,094
146158.9.16.0/20158.9.16.1 to 158.9.31.254158.9.31.2554,094
147158.9.32.0/20158.9.32.1 to 158.9.47.254158.9.47.2554,094
148158.9.48.0/20158.9.48.1 to 158.9.63.254158.9.63.2554,094
149158.9.64.0/20158.9.64.1 to 158.9.79.254158.9.79.2554,094
150158.9.80.0/20158.9.80.1 to 158.9.95.254158.9.95.2554,094
151158.9.96.0/20158.9.96.1 to 158.9.111.254158.9.111.2554,094
152158.9.112.0/20158.9.112.1 to 158.9.127.254158.9.127.2554,094
153158.9.128.0/20158.9.128.1 to 158.9.143.254158.9.143.2554,094
154158.9.144.0/20158.9.144.1 to 158.9.159.254158.9.159.2554,094
155158.9.160.0/20158.9.160.1 to 158.9.175.254158.9.175.2554,094
156158.9.176.0/20158.9.176.1 to 158.9.191.254158.9.191.2554,094
157158.9.192.0/20158.9.192.1 to 158.9.207.254158.9.207.2554,094
158158.9.208.0/20158.9.208.1 to 158.9.223.254158.9.223.2554,094
159158.9.224.0/20158.9.224.1 to 158.9.239.254158.9.239.2554,094
160158.9.240.0/20158.9.240.1 to 158.9.255.254158.9.255.2554,094
161158.10.0.0/20158.10.0.1 to 158.10.15.254158.10.15.2554,094
162158.10.16.0/20158.10.16.1 to 158.10.31.254158.10.31.2554,094
163158.10.32.0/20158.10.32.1 to 158.10.47.254158.10.47.2554,094
164158.10.48.0/20158.10.48.1 to 158.10.63.254158.10.63.2554,094
165158.10.64.0/20158.10.64.1 to 158.10.79.254158.10.79.2554,094
166158.10.80.0/20158.10.80.1 to 158.10.95.254158.10.95.2554,094
167158.10.96.0/20158.10.96.1 to 158.10.111.254158.10.111.2554,094
168158.10.112.0/20158.10.112.1 to 158.10.127.254158.10.127.2554,094
169158.10.128.0/20158.10.128.1 to 158.10.143.254158.10.143.2554,094
170158.10.144.0/20158.10.144.1 to 158.10.159.254158.10.159.2554,094
171158.10.160.0/20158.10.160.1 to 158.10.175.254158.10.175.2554,094
172158.10.176.0/20158.10.176.1 to 158.10.191.254158.10.191.2554,094
173158.10.192.0/20158.10.192.1 to 158.10.207.254158.10.207.2554,094
174158.10.208.0/20158.10.208.1 to 158.10.223.254158.10.223.2554,094
175158.10.224.0/20158.10.224.1 to 158.10.239.254158.10.239.2554,094
176158.10.240.0/20158.10.240.1 to 158.10.255.254158.10.255.2554,094
177158.11.0.0/20158.11.0.1 to 158.11.15.254158.11.15.2554,094
178158.11.16.0/20158.11.16.1 to 158.11.31.254158.11.31.2554,094
179158.11.32.0/20158.11.32.1 to 158.11.47.254158.11.47.2554,094
180158.11.48.0/20158.11.48.1 to 158.11.63.254158.11.63.2554,094
181158.11.64.0/20158.11.64.1 to 158.11.79.254158.11.79.2554,094
182158.11.80.0/20158.11.80.1 to 158.11.95.254158.11.95.2554,094
183158.11.96.0/20158.11.96.1 to 158.11.111.254158.11.111.2554,094
184158.11.112.0/20158.11.112.1 to 158.11.127.254158.11.127.2554,094
185158.11.128.0/20158.11.128.1 to 158.11.143.254158.11.143.2554,094
186158.11.144.0/20158.11.144.1 to 158.11.159.254158.11.159.2554,094
187158.11.160.0/20158.11.160.1 to 158.11.175.254158.11.175.2554,094
188158.11.176.0/20158.11.176.1 to 158.11.191.254158.11.191.2554,094
189158.11.192.0/20158.11.192.1 to 158.11.207.254158.11.207.2554,094
190158.11.208.0/20158.11.208.1 to 158.11.223.254158.11.223.2554,094
191158.11.224.0/20158.11.224.1 to 158.11.239.254158.11.239.2554,094
192158.11.240.0/20158.11.240.1 to 158.11.255.254158.11.255.2554,094
193158.12.0.0/20158.12.0.1 to 158.12.15.254158.12.15.2554,094
194158.12.16.0/20158.12.16.1 to 158.12.31.254158.12.31.2554,094
195158.12.32.0/20158.12.32.1 to 158.12.47.254158.12.47.2554,094
196158.12.48.0/20158.12.48.1 to 158.12.63.254158.12.63.2554,094
197158.12.64.0/20158.12.64.1 to 158.12.79.254158.12.79.2554,094
198158.12.80.0/20158.12.80.1 to 158.12.95.254158.12.95.2554,094
199158.12.96.0/20158.12.96.1 to 158.12.111.254158.12.111.2554,094
200158.12.112.0/20158.12.112.1 to 158.12.127.254158.12.127.2554,094
201158.12.128.0/20158.12.128.1 to 158.12.143.254158.12.143.2554,094
202158.12.144.0/20158.12.144.1 to 158.12.159.254158.12.159.2554,094
203158.12.160.0/20158.12.160.1 to 158.12.175.254158.12.175.2554,094
204158.12.176.0/20158.12.176.1 to 158.12.191.254158.12.191.2554,094
205158.12.192.0/20158.12.192.1 to 158.12.207.254158.12.207.2554,094
206158.12.208.0/20158.12.208.1 to 158.12.223.254158.12.223.2554,094
207158.12.224.0/20158.12.224.1 to 158.12.239.254158.12.239.2554,094
208158.12.240.0/20158.12.240.1 to 158.12.255.254158.12.255.2554,094
209158.13.0.0/20158.13.0.1 to 158.13.15.254158.13.15.2554,094
210158.13.16.0/20158.13.16.1 to 158.13.31.254158.13.31.2554,094
211158.13.32.0/20158.13.32.1 to 158.13.47.254158.13.47.2554,094
212158.13.48.0/20158.13.48.1 to 158.13.63.254158.13.63.2554,094
213158.13.64.0/20158.13.64.1 to 158.13.79.254158.13.79.2554,094
214158.13.80.0/20158.13.80.1 to 158.13.95.254158.13.95.2554,094
215158.13.96.0/20158.13.96.1 to 158.13.111.254158.13.111.2554,094
216158.13.112.0/20158.13.112.1 to 158.13.127.254158.13.127.2554,094
217158.13.128.0/20158.13.128.1 to 158.13.143.254158.13.143.2554,094
218158.13.144.0/20158.13.144.1 to 158.13.159.254158.13.159.2554,094
219158.13.160.0/20158.13.160.1 to 158.13.175.254158.13.175.2554,094
220158.13.176.0/20158.13.176.1 to 158.13.191.254158.13.191.2554,094
221158.13.192.0/20158.13.192.1 to 158.13.207.254158.13.207.2554,094
222158.13.208.0/20158.13.208.1 to 158.13.223.254158.13.223.2554,094
223158.13.224.0/20158.13.224.1 to 158.13.239.254158.13.239.2554,094
224158.13.240.0/20158.13.240.1 to 158.13.255.254158.13.255.2554,094
225158.14.0.0/20158.14.0.1 to 158.14.15.254158.14.15.2554,094
226158.14.16.0/20158.14.16.1 to 158.14.31.254158.14.31.2554,094
227158.14.32.0/20158.14.32.1 to 158.14.47.254158.14.47.2554,094
228158.14.48.0/20158.14.48.1 to 158.14.63.254158.14.63.2554,094
229158.14.64.0/20158.14.64.1 to 158.14.79.254158.14.79.2554,094
230158.14.80.0/20158.14.80.1 to 158.14.95.254158.14.95.2554,094
231158.14.96.0/20158.14.96.1 to 158.14.111.254158.14.111.2554,094
232158.14.112.0/20158.14.112.1 to 158.14.127.254158.14.127.2554,094
233158.14.128.0/20158.14.128.1 to 158.14.143.254158.14.143.2554,094
234158.14.144.0/20158.14.144.1 to 158.14.159.254158.14.159.2554,094
235158.14.160.0/20158.14.160.1 to 158.14.175.254158.14.175.2554,094
236158.14.176.0/20158.14.176.1 to 158.14.191.254158.14.191.2554,094
237158.14.192.0/20158.14.192.1 to 158.14.207.254158.14.207.2554,094
238158.14.208.0/20158.14.208.1 to 158.14.223.254158.14.223.2554,094
239158.14.224.0/20158.14.224.1 to 158.14.239.254158.14.239.2554,094
240158.14.240.0/20158.14.240.1 to 158.14.255.254158.14.255.2554,094
241158.15.0.0/20158.15.0.1 to 158.15.15.254158.15.15.2554,094
242158.15.16.0/20158.15.16.1 to 158.15.31.254158.15.31.2554,094
243158.15.32.0/20158.15.32.1 to 158.15.47.254158.15.47.2554,094
244158.15.48.0/20158.15.48.1 to 158.15.63.254158.15.63.2554,094
245158.15.64.0/20158.15.64.1 to 158.15.79.254158.15.79.2554,094
246158.15.80.0/20158.15.80.1 to 158.15.95.254158.15.95.2554,094
247158.15.96.0/20158.15.96.1 to 158.15.111.254158.15.111.2554,094
248158.15.112.0/20158.15.112.1 to 158.15.127.254158.15.127.2554,094
249158.15.128.0/20158.15.128.1 to 158.15.143.254158.15.143.2554,094
250158.15.144.0/20158.15.144.1 to 158.15.159.254158.15.159.2554,094
251158.15.160.0/20158.15.160.1 to 158.15.175.254158.15.175.2554,094
252158.15.176.0/20158.15.176.1 to 158.15.191.254158.15.191.2554,094
253158.15.192.0/20158.15.192.1 to 158.15.207.254158.15.207.2554,094
254158.15.208.0/20158.15.208.1 to 158.15.223.254158.15.223.2554,094
255158.15.224.0/20158.15.224.1 to 158.15.239.254158.15.239.2554,094
256158.15.240.0/20158.15.240.1 to 158.15.255.254158.15.255.2554,094

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.