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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.

Network154.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
154.0.0.0
Broadcast address
155.255.255.255
First usable
154.0.0.1
Last usable
155.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
B (default /16)
As numbers
Hex 9A000000 · Integer 2583691264 to 2617245695
Reverse DNS zones
154.in-addr.arpa
155.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011010.00000000.00000000.00000000154.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10011010.00000000.00000000.00000000154.0.0.0
Broadcast10011011.11111111.11111111.11111111155.255.255.255
Split into smaller subnets/19
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

154.0.0.0/7 makes 4,096 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1154.0.0.0/19154.0.0.1 to 154.0.31.254154.0.31.2558,190
2154.0.32.0/19154.0.32.1 to 154.0.63.254154.0.63.2558,190
3154.0.64.0/19154.0.64.1 to 154.0.95.254154.0.95.2558,190
4154.0.96.0/19154.0.96.1 to 154.0.127.254154.0.127.2558,190
5154.0.128.0/19154.0.128.1 to 154.0.159.254154.0.159.2558,190
6154.0.160.0/19154.0.160.1 to 154.0.191.254154.0.191.2558,190
7154.0.192.0/19154.0.192.1 to 154.0.223.254154.0.223.2558,190
8154.0.224.0/19154.0.224.1 to 154.0.255.254154.0.255.2558,190
9154.1.0.0/19154.1.0.1 to 154.1.31.254154.1.31.2558,190
10154.1.32.0/19154.1.32.1 to 154.1.63.254154.1.63.2558,190
11154.1.64.0/19154.1.64.1 to 154.1.95.254154.1.95.2558,190
12154.1.96.0/19154.1.96.1 to 154.1.127.254154.1.127.2558,190
13154.1.128.0/19154.1.128.1 to 154.1.159.254154.1.159.2558,190
14154.1.160.0/19154.1.160.1 to 154.1.191.254154.1.191.2558,190
15154.1.192.0/19154.1.192.1 to 154.1.223.254154.1.223.2558,190
16154.1.224.0/19154.1.224.1 to 154.1.255.254154.1.255.2558,190
17154.2.0.0/19154.2.0.1 to 154.2.31.254154.2.31.2558,190
18154.2.32.0/19154.2.32.1 to 154.2.63.254154.2.63.2558,190
19154.2.64.0/19154.2.64.1 to 154.2.95.254154.2.95.2558,190
20154.2.96.0/19154.2.96.1 to 154.2.127.254154.2.127.2558,190
21154.2.128.0/19154.2.128.1 to 154.2.159.254154.2.159.2558,190
22154.2.160.0/19154.2.160.1 to 154.2.191.254154.2.191.2558,190
23154.2.192.0/19154.2.192.1 to 154.2.223.254154.2.223.2558,190
24154.2.224.0/19154.2.224.1 to 154.2.255.254154.2.255.2558,190
25154.3.0.0/19154.3.0.1 to 154.3.31.254154.3.31.2558,190
26154.3.32.0/19154.3.32.1 to 154.3.63.254154.3.63.2558,190
27154.3.64.0/19154.3.64.1 to 154.3.95.254154.3.95.2558,190
28154.3.96.0/19154.3.96.1 to 154.3.127.254154.3.127.2558,190
29154.3.128.0/19154.3.128.1 to 154.3.159.254154.3.159.2558,190
30154.3.160.0/19154.3.160.1 to 154.3.191.254154.3.191.2558,190
31154.3.192.0/19154.3.192.1 to 154.3.223.254154.3.223.2558,190
32154.3.224.0/19154.3.224.1 to 154.3.255.254154.3.255.2558,190
33154.4.0.0/19154.4.0.1 to 154.4.31.254154.4.31.2558,190
34154.4.32.0/19154.4.32.1 to 154.4.63.254154.4.63.2558,190
35154.4.64.0/19154.4.64.1 to 154.4.95.254154.4.95.2558,190
36154.4.96.0/19154.4.96.1 to 154.4.127.254154.4.127.2558,190
37154.4.128.0/19154.4.128.1 to 154.4.159.254154.4.159.2558,190
38154.4.160.0/19154.4.160.1 to 154.4.191.254154.4.191.2558,190
39154.4.192.0/19154.4.192.1 to 154.4.223.254154.4.223.2558,190
40154.4.224.0/19154.4.224.1 to 154.4.255.254154.4.255.2558,190
41154.5.0.0/19154.5.0.1 to 154.5.31.254154.5.31.2558,190
42154.5.32.0/19154.5.32.1 to 154.5.63.254154.5.63.2558,190
43154.5.64.0/19154.5.64.1 to 154.5.95.254154.5.95.2558,190
44154.5.96.0/19154.5.96.1 to 154.5.127.254154.5.127.2558,190
45154.5.128.0/19154.5.128.1 to 154.5.159.254154.5.159.2558,190
46154.5.160.0/19154.5.160.1 to 154.5.191.254154.5.191.2558,190
47154.5.192.0/19154.5.192.1 to 154.5.223.254154.5.223.2558,190
48154.5.224.0/19154.5.224.1 to 154.5.255.254154.5.255.2558,190
49154.6.0.0/19154.6.0.1 to 154.6.31.254154.6.31.2558,190
50154.6.32.0/19154.6.32.1 to 154.6.63.254154.6.63.2558,190
51154.6.64.0/19154.6.64.1 to 154.6.95.254154.6.95.2558,190
52154.6.96.0/19154.6.96.1 to 154.6.127.254154.6.127.2558,190
53154.6.128.0/19154.6.128.1 to 154.6.159.254154.6.159.2558,190
54154.6.160.0/19154.6.160.1 to 154.6.191.254154.6.191.2558,190
55154.6.192.0/19154.6.192.1 to 154.6.223.254154.6.223.2558,190
56154.6.224.0/19154.6.224.1 to 154.6.255.254154.6.255.2558,190
57154.7.0.0/19154.7.0.1 to 154.7.31.254154.7.31.2558,190
58154.7.32.0/19154.7.32.1 to 154.7.63.254154.7.63.2558,190
59154.7.64.0/19154.7.64.1 to 154.7.95.254154.7.95.2558,190
60154.7.96.0/19154.7.96.1 to 154.7.127.254154.7.127.2558,190
61154.7.128.0/19154.7.128.1 to 154.7.159.254154.7.159.2558,190
62154.7.160.0/19154.7.160.1 to 154.7.191.254154.7.191.2558,190
63154.7.192.0/19154.7.192.1 to 154.7.223.254154.7.223.2558,190
64154.7.224.0/19154.7.224.1 to 154.7.255.254154.7.255.2558,190
65154.8.0.0/19154.8.0.1 to 154.8.31.254154.8.31.2558,190
66154.8.32.0/19154.8.32.1 to 154.8.63.254154.8.63.2558,190
67154.8.64.0/19154.8.64.1 to 154.8.95.254154.8.95.2558,190
68154.8.96.0/19154.8.96.1 to 154.8.127.254154.8.127.2558,190
69154.8.128.0/19154.8.128.1 to 154.8.159.254154.8.159.2558,190
70154.8.160.0/19154.8.160.1 to 154.8.191.254154.8.191.2558,190
71154.8.192.0/19154.8.192.1 to 154.8.223.254154.8.223.2558,190
72154.8.224.0/19154.8.224.1 to 154.8.255.254154.8.255.2558,190
73154.9.0.0/19154.9.0.1 to 154.9.31.254154.9.31.2558,190
74154.9.32.0/19154.9.32.1 to 154.9.63.254154.9.63.2558,190
75154.9.64.0/19154.9.64.1 to 154.9.95.254154.9.95.2558,190
76154.9.96.0/19154.9.96.1 to 154.9.127.254154.9.127.2558,190
77154.9.128.0/19154.9.128.1 to 154.9.159.254154.9.159.2558,190
78154.9.160.0/19154.9.160.1 to 154.9.191.254154.9.191.2558,190
79154.9.192.0/19154.9.192.1 to 154.9.223.254154.9.223.2558,190
80154.9.224.0/19154.9.224.1 to 154.9.255.254154.9.255.2558,190
81154.10.0.0/19154.10.0.1 to 154.10.31.254154.10.31.2558,190
82154.10.32.0/19154.10.32.1 to 154.10.63.254154.10.63.2558,190
83154.10.64.0/19154.10.64.1 to 154.10.95.254154.10.95.2558,190
84154.10.96.0/19154.10.96.1 to 154.10.127.254154.10.127.2558,190
85154.10.128.0/19154.10.128.1 to 154.10.159.254154.10.159.2558,190
86154.10.160.0/19154.10.160.1 to 154.10.191.254154.10.191.2558,190
87154.10.192.0/19154.10.192.1 to 154.10.223.254154.10.223.2558,190
88154.10.224.0/19154.10.224.1 to 154.10.255.254154.10.255.2558,190
89154.11.0.0/19154.11.0.1 to 154.11.31.254154.11.31.2558,190
90154.11.32.0/19154.11.32.1 to 154.11.63.254154.11.63.2558,190
91154.11.64.0/19154.11.64.1 to 154.11.95.254154.11.95.2558,190
92154.11.96.0/19154.11.96.1 to 154.11.127.254154.11.127.2558,190
93154.11.128.0/19154.11.128.1 to 154.11.159.254154.11.159.2558,190
94154.11.160.0/19154.11.160.1 to 154.11.191.254154.11.191.2558,190
95154.11.192.0/19154.11.192.1 to 154.11.223.254154.11.223.2558,190
96154.11.224.0/19154.11.224.1 to 154.11.255.254154.11.255.2558,190
97154.12.0.0/19154.12.0.1 to 154.12.31.254154.12.31.2558,190
98154.12.32.0/19154.12.32.1 to 154.12.63.254154.12.63.2558,190
99154.12.64.0/19154.12.64.1 to 154.12.95.254154.12.95.2558,190
100154.12.96.0/19154.12.96.1 to 154.12.127.254154.12.127.2558,190
101154.12.128.0/19154.12.128.1 to 154.12.159.254154.12.159.2558,190
102154.12.160.0/19154.12.160.1 to 154.12.191.254154.12.191.2558,190
103154.12.192.0/19154.12.192.1 to 154.12.223.254154.12.223.2558,190
104154.12.224.0/19154.12.224.1 to 154.12.255.254154.12.255.2558,190
105154.13.0.0/19154.13.0.1 to 154.13.31.254154.13.31.2558,190
106154.13.32.0/19154.13.32.1 to 154.13.63.254154.13.63.2558,190
107154.13.64.0/19154.13.64.1 to 154.13.95.254154.13.95.2558,190
108154.13.96.0/19154.13.96.1 to 154.13.127.254154.13.127.2558,190
109154.13.128.0/19154.13.128.1 to 154.13.159.254154.13.159.2558,190
110154.13.160.0/19154.13.160.1 to 154.13.191.254154.13.191.2558,190
111154.13.192.0/19154.13.192.1 to 154.13.223.254154.13.223.2558,190
112154.13.224.0/19154.13.224.1 to 154.13.255.254154.13.255.2558,190
113154.14.0.0/19154.14.0.1 to 154.14.31.254154.14.31.2558,190
114154.14.32.0/19154.14.32.1 to 154.14.63.254154.14.63.2558,190
115154.14.64.0/19154.14.64.1 to 154.14.95.254154.14.95.2558,190
116154.14.96.0/19154.14.96.1 to 154.14.127.254154.14.127.2558,190
117154.14.128.0/19154.14.128.1 to 154.14.159.254154.14.159.2558,190
118154.14.160.0/19154.14.160.1 to 154.14.191.254154.14.191.2558,190
119154.14.192.0/19154.14.192.1 to 154.14.223.254154.14.223.2558,190
120154.14.224.0/19154.14.224.1 to 154.14.255.254154.14.255.2558,190
121154.15.0.0/19154.15.0.1 to 154.15.31.254154.15.31.2558,190
122154.15.32.0/19154.15.32.1 to 154.15.63.254154.15.63.2558,190
123154.15.64.0/19154.15.64.1 to 154.15.95.254154.15.95.2558,190
124154.15.96.0/19154.15.96.1 to 154.15.127.254154.15.127.2558,190
125154.15.128.0/19154.15.128.1 to 154.15.159.254154.15.159.2558,190
126154.15.160.0/19154.15.160.1 to 154.15.191.254154.15.191.2558,190
127154.15.192.0/19154.15.192.1 to 154.15.223.254154.15.223.2558,190
128154.15.224.0/19154.15.224.1 to 154.15.255.254154.15.255.2558,190
129154.16.0.0/19154.16.0.1 to 154.16.31.254154.16.31.2558,190
130154.16.32.0/19154.16.32.1 to 154.16.63.254154.16.63.2558,190
131154.16.64.0/19154.16.64.1 to 154.16.95.254154.16.95.2558,190
132154.16.96.0/19154.16.96.1 to 154.16.127.254154.16.127.2558,190
133154.16.128.0/19154.16.128.1 to 154.16.159.254154.16.159.2558,190
134154.16.160.0/19154.16.160.1 to 154.16.191.254154.16.191.2558,190
135154.16.192.0/19154.16.192.1 to 154.16.223.254154.16.223.2558,190
136154.16.224.0/19154.16.224.1 to 154.16.255.254154.16.255.2558,190
137154.17.0.0/19154.17.0.1 to 154.17.31.254154.17.31.2558,190
138154.17.32.0/19154.17.32.1 to 154.17.63.254154.17.63.2558,190
139154.17.64.0/19154.17.64.1 to 154.17.95.254154.17.95.2558,190
140154.17.96.0/19154.17.96.1 to 154.17.127.254154.17.127.2558,190
141154.17.128.0/19154.17.128.1 to 154.17.159.254154.17.159.2558,190
142154.17.160.0/19154.17.160.1 to 154.17.191.254154.17.191.2558,190
143154.17.192.0/19154.17.192.1 to 154.17.223.254154.17.223.2558,190
144154.17.224.0/19154.17.224.1 to 154.17.255.254154.17.255.2558,190
145154.18.0.0/19154.18.0.1 to 154.18.31.254154.18.31.2558,190
146154.18.32.0/19154.18.32.1 to 154.18.63.254154.18.63.2558,190
147154.18.64.0/19154.18.64.1 to 154.18.95.254154.18.95.2558,190
148154.18.96.0/19154.18.96.1 to 154.18.127.254154.18.127.2558,190
149154.18.128.0/19154.18.128.1 to 154.18.159.254154.18.159.2558,190
150154.18.160.0/19154.18.160.1 to 154.18.191.254154.18.191.2558,190
151154.18.192.0/19154.18.192.1 to 154.18.223.254154.18.223.2558,190
152154.18.224.0/19154.18.224.1 to 154.18.255.254154.18.255.2558,190
153154.19.0.0/19154.19.0.1 to 154.19.31.254154.19.31.2558,190
154154.19.32.0/19154.19.32.1 to 154.19.63.254154.19.63.2558,190
155154.19.64.0/19154.19.64.1 to 154.19.95.254154.19.95.2558,190
156154.19.96.0/19154.19.96.1 to 154.19.127.254154.19.127.2558,190
157154.19.128.0/19154.19.128.1 to 154.19.159.254154.19.159.2558,190
158154.19.160.0/19154.19.160.1 to 154.19.191.254154.19.191.2558,190
159154.19.192.0/19154.19.192.1 to 154.19.223.254154.19.223.2558,190
160154.19.224.0/19154.19.224.1 to 154.19.255.254154.19.255.2558,190
161154.20.0.0/19154.20.0.1 to 154.20.31.254154.20.31.2558,190
162154.20.32.0/19154.20.32.1 to 154.20.63.254154.20.63.2558,190
163154.20.64.0/19154.20.64.1 to 154.20.95.254154.20.95.2558,190
164154.20.96.0/19154.20.96.1 to 154.20.127.254154.20.127.2558,190
165154.20.128.0/19154.20.128.1 to 154.20.159.254154.20.159.2558,190
166154.20.160.0/19154.20.160.1 to 154.20.191.254154.20.191.2558,190
167154.20.192.0/19154.20.192.1 to 154.20.223.254154.20.223.2558,190
168154.20.224.0/19154.20.224.1 to 154.20.255.254154.20.255.2558,190
169154.21.0.0/19154.21.0.1 to 154.21.31.254154.21.31.2558,190
170154.21.32.0/19154.21.32.1 to 154.21.63.254154.21.63.2558,190
171154.21.64.0/19154.21.64.1 to 154.21.95.254154.21.95.2558,190
172154.21.96.0/19154.21.96.1 to 154.21.127.254154.21.127.2558,190
173154.21.128.0/19154.21.128.1 to 154.21.159.254154.21.159.2558,190
174154.21.160.0/19154.21.160.1 to 154.21.191.254154.21.191.2558,190
175154.21.192.0/19154.21.192.1 to 154.21.223.254154.21.223.2558,190
176154.21.224.0/19154.21.224.1 to 154.21.255.254154.21.255.2558,190
177154.22.0.0/19154.22.0.1 to 154.22.31.254154.22.31.2558,190
178154.22.32.0/19154.22.32.1 to 154.22.63.254154.22.63.2558,190
179154.22.64.0/19154.22.64.1 to 154.22.95.254154.22.95.2558,190
180154.22.96.0/19154.22.96.1 to 154.22.127.254154.22.127.2558,190
181154.22.128.0/19154.22.128.1 to 154.22.159.254154.22.159.2558,190
182154.22.160.0/19154.22.160.1 to 154.22.191.254154.22.191.2558,190
183154.22.192.0/19154.22.192.1 to 154.22.223.254154.22.223.2558,190
184154.22.224.0/19154.22.224.1 to 154.22.255.254154.22.255.2558,190
185154.23.0.0/19154.23.0.1 to 154.23.31.254154.23.31.2558,190
186154.23.32.0/19154.23.32.1 to 154.23.63.254154.23.63.2558,190
187154.23.64.0/19154.23.64.1 to 154.23.95.254154.23.95.2558,190
188154.23.96.0/19154.23.96.1 to 154.23.127.254154.23.127.2558,190
189154.23.128.0/19154.23.128.1 to 154.23.159.254154.23.159.2558,190
190154.23.160.0/19154.23.160.1 to 154.23.191.254154.23.191.2558,190
191154.23.192.0/19154.23.192.1 to 154.23.223.254154.23.223.2558,190
192154.23.224.0/19154.23.224.1 to 154.23.255.254154.23.255.2558,190
193154.24.0.0/19154.24.0.1 to 154.24.31.254154.24.31.2558,190
194154.24.32.0/19154.24.32.1 to 154.24.63.254154.24.63.2558,190
195154.24.64.0/19154.24.64.1 to 154.24.95.254154.24.95.2558,190
196154.24.96.0/19154.24.96.1 to 154.24.127.254154.24.127.2558,190
197154.24.128.0/19154.24.128.1 to 154.24.159.254154.24.159.2558,190
198154.24.160.0/19154.24.160.1 to 154.24.191.254154.24.191.2558,190
199154.24.192.0/19154.24.192.1 to 154.24.223.254154.24.223.2558,190
200154.24.224.0/19154.24.224.1 to 154.24.255.254154.24.255.2558,190
201154.25.0.0/19154.25.0.1 to 154.25.31.254154.25.31.2558,190
202154.25.32.0/19154.25.32.1 to 154.25.63.254154.25.63.2558,190
203154.25.64.0/19154.25.64.1 to 154.25.95.254154.25.95.2558,190
204154.25.96.0/19154.25.96.1 to 154.25.127.254154.25.127.2558,190
205154.25.128.0/19154.25.128.1 to 154.25.159.254154.25.159.2558,190
206154.25.160.0/19154.25.160.1 to 154.25.191.254154.25.191.2558,190
207154.25.192.0/19154.25.192.1 to 154.25.223.254154.25.223.2558,190
208154.25.224.0/19154.25.224.1 to 154.25.255.254154.25.255.2558,190
209154.26.0.0/19154.26.0.1 to 154.26.31.254154.26.31.2558,190
210154.26.32.0/19154.26.32.1 to 154.26.63.254154.26.63.2558,190
211154.26.64.0/19154.26.64.1 to 154.26.95.254154.26.95.2558,190
212154.26.96.0/19154.26.96.1 to 154.26.127.254154.26.127.2558,190
213154.26.128.0/19154.26.128.1 to 154.26.159.254154.26.159.2558,190
214154.26.160.0/19154.26.160.1 to 154.26.191.254154.26.191.2558,190
215154.26.192.0/19154.26.192.1 to 154.26.223.254154.26.223.2558,190
216154.26.224.0/19154.26.224.1 to 154.26.255.254154.26.255.2558,190
217154.27.0.0/19154.27.0.1 to 154.27.31.254154.27.31.2558,190
218154.27.32.0/19154.27.32.1 to 154.27.63.254154.27.63.2558,190
219154.27.64.0/19154.27.64.1 to 154.27.95.254154.27.95.2558,190
220154.27.96.0/19154.27.96.1 to 154.27.127.254154.27.127.2558,190
221154.27.128.0/19154.27.128.1 to 154.27.159.254154.27.159.2558,190
222154.27.160.0/19154.27.160.1 to 154.27.191.254154.27.191.2558,190
223154.27.192.0/19154.27.192.1 to 154.27.223.254154.27.223.2558,190
224154.27.224.0/19154.27.224.1 to 154.27.255.254154.27.255.2558,190
225154.28.0.0/19154.28.0.1 to 154.28.31.254154.28.31.2558,190
226154.28.32.0/19154.28.32.1 to 154.28.63.254154.28.63.2558,190
227154.28.64.0/19154.28.64.1 to 154.28.95.254154.28.95.2558,190
228154.28.96.0/19154.28.96.1 to 154.28.127.254154.28.127.2558,190
229154.28.128.0/19154.28.128.1 to 154.28.159.254154.28.159.2558,190
230154.28.160.0/19154.28.160.1 to 154.28.191.254154.28.191.2558,190
231154.28.192.0/19154.28.192.1 to 154.28.223.254154.28.223.2558,190
232154.28.224.0/19154.28.224.1 to 154.28.255.254154.28.255.2558,190
233154.29.0.0/19154.29.0.1 to 154.29.31.254154.29.31.2558,190
234154.29.32.0/19154.29.32.1 to 154.29.63.254154.29.63.2558,190
235154.29.64.0/19154.29.64.1 to 154.29.95.254154.29.95.2558,190
236154.29.96.0/19154.29.96.1 to 154.29.127.254154.29.127.2558,190
237154.29.128.0/19154.29.128.1 to 154.29.159.254154.29.159.2558,190
238154.29.160.0/19154.29.160.1 to 154.29.191.254154.29.191.2558,190
239154.29.192.0/19154.29.192.1 to 154.29.223.254154.29.223.2558,190
240154.29.224.0/19154.29.224.1 to 154.29.255.254154.29.255.2558,190
241154.30.0.0/19154.30.0.1 to 154.30.31.254154.30.31.2558,190
242154.30.32.0/19154.30.32.1 to 154.30.63.254154.30.63.2558,190
243154.30.64.0/19154.30.64.1 to 154.30.95.254154.30.95.2558,190
244154.30.96.0/19154.30.96.1 to 154.30.127.254154.30.127.2558,190
245154.30.128.0/19154.30.128.1 to 154.30.159.254154.30.159.2558,190
246154.30.160.0/19154.30.160.1 to 154.30.191.254154.30.191.2558,190
247154.30.192.0/19154.30.192.1 to 154.30.223.254154.30.223.2558,190
248154.30.224.0/19154.30.224.1 to 154.30.255.254154.30.255.2558,190
249154.31.0.0/19154.31.0.1 to 154.31.31.254154.31.31.2558,190
250154.31.32.0/19154.31.32.1 to 154.31.63.254154.31.63.2558,190
251154.31.64.0/19154.31.64.1 to 154.31.95.254154.31.95.2558,190
252154.31.96.0/19154.31.96.1 to 154.31.127.254154.31.127.2558,190
253154.31.128.0/19154.31.128.1 to 154.31.159.254154.31.159.2558,190
254154.31.160.0/19154.31.160.1 to 154.31.191.254154.31.191.2558,190
255154.31.192.0/19154.31.192.1 to 154.31.223.254154.31.223.2558,190
256154.31.224.0/19154.31.224.1 to 154.31.255.254154.31.255.2558,190

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.