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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.

Network147.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
147.0.0.0
Broadcast address
147.127.255.255
First usable
147.0.0.1
Last usable
147.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
B (default /16)
As numbers
Hex 93000000 · Integer 2466250752 to 2474639359
Reverse DNS zones
0.147.in-addr.arpa
1.147.in-addr.arpa
2.147.in-addr.arpa
3.147.in-addr.arpa
4.147.in-addr.arpa
5.147.in-addr.arpa
6.147.in-addr.arpa
7.147.in-addr.arpa
8.147.in-addr.arpa
9.147.in-addr.arpa
10.147.in-addr.arpa
11.147.in-addr.arpa
12.147.in-addr.arpa
13.147.in-addr.arpa
14.147.in-addr.arpa
15.147.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10010011.00000000.00000000.00000000147.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network10010011.00000000.00000000.00000000147.0.0.0
Broadcast10010011.01111111.11111111.11111111147.127.255.255
Split into smaller subnets/19
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

147.0.0.0/9 makes 1,024 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1147.0.0.0/19147.0.0.1 to 147.0.31.254147.0.31.2558,190
2147.0.32.0/19147.0.32.1 to 147.0.63.254147.0.63.2558,190
3147.0.64.0/19147.0.64.1 to 147.0.95.254147.0.95.2558,190
4147.0.96.0/19147.0.96.1 to 147.0.127.254147.0.127.2558,190
5147.0.128.0/19147.0.128.1 to 147.0.159.254147.0.159.2558,190
6147.0.160.0/19147.0.160.1 to 147.0.191.254147.0.191.2558,190
7147.0.192.0/19147.0.192.1 to 147.0.223.254147.0.223.2558,190
8147.0.224.0/19147.0.224.1 to 147.0.255.254147.0.255.2558,190
9147.1.0.0/19147.1.0.1 to 147.1.31.254147.1.31.2558,190
10147.1.32.0/19147.1.32.1 to 147.1.63.254147.1.63.2558,190
11147.1.64.0/19147.1.64.1 to 147.1.95.254147.1.95.2558,190
12147.1.96.0/19147.1.96.1 to 147.1.127.254147.1.127.2558,190
13147.1.128.0/19147.1.128.1 to 147.1.159.254147.1.159.2558,190
14147.1.160.0/19147.1.160.1 to 147.1.191.254147.1.191.2558,190
15147.1.192.0/19147.1.192.1 to 147.1.223.254147.1.223.2558,190
16147.1.224.0/19147.1.224.1 to 147.1.255.254147.1.255.2558,190
17147.2.0.0/19147.2.0.1 to 147.2.31.254147.2.31.2558,190
18147.2.32.0/19147.2.32.1 to 147.2.63.254147.2.63.2558,190
19147.2.64.0/19147.2.64.1 to 147.2.95.254147.2.95.2558,190
20147.2.96.0/19147.2.96.1 to 147.2.127.254147.2.127.2558,190
21147.2.128.0/19147.2.128.1 to 147.2.159.254147.2.159.2558,190
22147.2.160.0/19147.2.160.1 to 147.2.191.254147.2.191.2558,190
23147.2.192.0/19147.2.192.1 to 147.2.223.254147.2.223.2558,190
24147.2.224.0/19147.2.224.1 to 147.2.255.254147.2.255.2558,190
25147.3.0.0/19147.3.0.1 to 147.3.31.254147.3.31.2558,190
26147.3.32.0/19147.3.32.1 to 147.3.63.254147.3.63.2558,190
27147.3.64.0/19147.3.64.1 to 147.3.95.254147.3.95.2558,190
28147.3.96.0/19147.3.96.1 to 147.3.127.254147.3.127.2558,190
29147.3.128.0/19147.3.128.1 to 147.3.159.254147.3.159.2558,190
30147.3.160.0/19147.3.160.1 to 147.3.191.254147.3.191.2558,190
31147.3.192.0/19147.3.192.1 to 147.3.223.254147.3.223.2558,190
32147.3.224.0/19147.3.224.1 to 147.3.255.254147.3.255.2558,190
33147.4.0.0/19147.4.0.1 to 147.4.31.254147.4.31.2558,190
34147.4.32.0/19147.4.32.1 to 147.4.63.254147.4.63.2558,190
35147.4.64.0/19147.4.64.1 to 147.4.95.254147.4.95.2558,190
36147.4.96.0/19147.4.96.1 to 147.4.127.254147.4.127.2558,190
37147.4.128.0/19147.4.128.1 to 147.4.159.254147.4.159.2558,190
38147.4.160.0/19147.4.160.1 to 147.4.191.254147.4.191.2558,190
39147.4.192.0/19147.4.192.1 to 147.4.223.254147.4.223.2558,190
40147.4.224.0/19147.4.224.1 to 147.4.255.254147.4.255.2558,190
41147.5.0.0/19147.5.0.1 to 147.5.31.254147.5.31.2558,190
42147.5.32.0/19147.5.32.1 to 147.5.63.254147.5.63.2558,190
43147.5.64.0/19147.5.64.1 to 147.5.95.254147.5.95.2558,190
44147.5.96.0/19147.5.96.1 to 147.5.127.254147.5.127.2558,190
45147.5.128.0/19147.5.128.1 to 147.5.159.254147.5.159.2558,190
46147.5.160.0/19147.5.160.1 to 147.5.191.254147.5.191.2558,190
47147.5.192.0/19147.5.192.1 to 147.5.223.254147.5.223.2558,190
48147.5.224.0/19147.5.224.1 to 147.5.255.254147.5.255.2558,190
49147.6.0.0/19147.6.0.1 to 147.6.31.254147.6.31.2558,190
50147.6.32.0/19147.6.32.1 to 147.6.63.254147.6.63.2558,190
51147.6.64.0/19147.6.64.1 to 147.6.95.254147.6.95.2558,190
52147.6.96.0/19147.6.96.1 to 147.6.127.254147.6.127.2558,190
53147.6.128.0/19147.6.128.1 to 147.6.159.254147.6.159.2558,190
54147.6.160.0/19147.6.160.1 to 147.6.191.254147.6.191.2558,190
55147.6.192.0/19147.6.192.1 to 147.6.223.254147.6.223.2558,190
56147.6.224.0/19147.6.224.1 to 147.6.255.254147.6.255.2558,190
57147.7.0.0/19147.7.0.1 to 147.7.31.254147.7.31.2558,190
58147.7.32.0/19147.7.32.1 to 147.7.63.254147.7.63.2558,190
59147.7.64.0/19147.7.64.1 to 147.7.95.254147.7.95.2558,190
60147.7.96.0/19147.7.96.1 to 147.7.127.254147.7.127.2558,190
61147.7.128.0/19147.7.128.1 to 147.7.159.254147.7.159.2558,190
62147.7.160.0/19147.7.160.1 to 147.7.191.254147.7.191.2558,190
63147.7.192.0/19147.7.192.1 to 147.7.223.254147.7.223.2558,190
64147.7.224.0/19147.7.224.1 to 147.7.255.254147.7.255.2558,190
65147.8.0.0/19147.8.0.1 to 147.8.31.254147.8.31.2558,190
66147.8.32.0/19147.8.32.1 to 147.8.63.254147.8.63.2558,190
67147.8.64.0/19147.8.64.1 to 147.8.95.254147.8.95.2558,190
68147.8.96.0/19147.8.96.1 to 147.8.127.254147.8.127.2558,190
69147.8.128.0/19147.8.128.1 to 147.8.159.254147.8.159.2558,190
70147.8.160.0/19147.8.160.1 to 147.8.191.254147.8.191.2558,190
71147.8.192.0/19147.8.192.1 to 147.8.223.254147.8.223.2558,190
72147.8.224.0/19147.8.224.1 to 147.8.255.254147.8.255.2558,190
73147.9.0.0/19147.9.0.1 to 147.9.31.254147.9.31.2558,190
74147.9.32.0/19147.9.32.1 to 147.9.63.254147.9.63.2558,190
75147.9.64.0/19147.9.64.1 to 147.9.95.254147.9.95.2558,190
76147.9.96.0/19147.9.96.1 to 147.9.127.254147.9.127.2558,190
77147.9.128.0/19147.9.128.1 to 147.9.159.254147.9.159.2558,190
78147.9.160.0/19147.9.160.1 to 147.9.191.254147.9.191.2558,190
79147.9.192.0/19147.9.192.1 to 147.9.223.254147.9.223.2558,190
80147.9.224.0/19147.9.224.1 to 147.9.255.254147.9.255.2558,190
81147.10.0.0/19147.10.0.1 to 147.10.31.254147.10.31.2558,190
82147.10.32.0/19147.10.32.1 to 147.10.63.254147.10.63.2558,190
83147.10.64.0/19147.10.64.1 to 147.10.95.254147.10.95.2558,190
84147.10.96.0/19147.10.96.1 to 147.10.127.254147.10.127.2558,190
85147.10.128.0/19147.10.128.1 to 147.10.159.254147.10.159.2558,190
86147.10.160.0/19147.10.160.1 to 147.10.191.254147.10.191.2558,190
87147.10.192.0/19147.10.192.1 to 147.10.223.254147.10.223.2558,190
88147.10.224.0/19147.10.224.1 to 147.10.255.254147.10.255.2558,190
89147.11.0.0/19147.11.0.1 to 147.11.31.254147.11.31.2558,190
90147.11.32.0/19147.11.32.1 to 147.11.63.254147.11.63.2558,190
91147.11.64.0/19147.11.64.1 to 147.11.95.254147.11.95.2558,190
92147.11.96.0/19147.11.96.1 to 147.11.127.254147.11.127.2558,190
93147.11.128.0/19147.11.128.1 to 147.11.159.254147.11.159.2558,190
94147.11.160.0/19147.11.160.1 to 147.11.191.254147.11.191.2558,190
95147.11.192.0/19147.11.192.1 to 147.11.223.254147.11.223.2558,190
96147.11.224.0/19147.11.224.1 to 147.11.255.254147.11.255.2558,190
97147.12.0.0/19147.12.0.1 to 147.12.31.254147.12.31.2558,190
98147.12.32.0/19147.12.32.1 to 147.12.63.254147.12.63.2558,190
99147.12.64.0/19147.12.64.1 to 147.12.95.254147.12.95.2558,190
100147.12.96.0/19147.12.96.1 to 147.12.127.254147.12.127.2558,190
101147.12.128.0/19147.12.128.1 to 147.12.159.254147.12.159.2558,190
102147.12.160.0/19147.12.160.1 to 147.12.191.254147.12.191.2558,190
103147.12.192.0/19147.12.192.1 to 147.12.223.254147.12.223.2558,190
104147.12.224.0/19147.12.224.1 to 147.12.255.254147.12.255.2558,190
105147.13.0.0/19147.13.0.1 to 147.13.31.254147.13.31.2558,190
106147.13.32.0/19147.13.32.1 to 147.13.63.254147.13.63.2558,190
107147.13.64.0/19147.13.64.1 to 147.13.95.254147.13.95.2558,190
108147.13.96.0/19147.13.96.1 to 147.13.127.254147.13.127.2558,190
109147.13.128.0/19147.13.128.1 to 147.13.159.254147.13.159.2558,190
110147.13.160.0/19147.13.160.1 to 147.13.191.254147.13.191.2558,190
111147.13.192.0/19147.13.192.1 to 147.13.223.254147.13.223.2558,190
112147.13.224.0/19147.13.224.1 to 147.13.255.254147.13.255.2558,190
113147.14.0.0/19147.14.0.1 to 147.14.31.254147.14.31.2558,190
114147.14.32.0/19147.14.32.1 to 147.14.63.254147.14.63.2558,190
115147.14.64.0/19147.14.64.1 to 147.14.95.254147.14.95.2558,190
116147.14.96.0/19147.14.96.1 to 147.14.127.254147.14.127.2558,190
117147.14.128.0/19147.14.128.1 to 147.14.159.254147.14.159.2558,190
118147.14.160.0/19147.14.160.1 to 147.14.191.254147.14.191.2558,190
119147.14.192.0/19147.14.192.1 to 147.14.223.254147.14.223.2558,190
120147.14.224.0/19147.14.224.1 to 147.14.255.254147.14.255.2558,190
121147.15.0.0/19147.15.0.1 to 147.15.31.254147.15.31.2558,190
122147.15.32.0/19147.15.32.1 to 147.15.63.254147.15.63.2558,190
123147.15.64.0/19147.15.64.1 to 147.15.95.254147.15.95.2558,190
124147.15.96.0/19147.15.96.1 to 147.15.127.254147.15.127.2558,190
125147.15.128.0/19147.15.128.1 to 147.15.159.254147.15.159.2558,190
126147.15.160.0/19147.15.160.1 to 147.15.191.254147.15.191.2558,190
127147.15.192.0/19147.15.192.1 to 147.15.223.254147.15.223.2558,190
128147.15.224.0/19147.15.224.1 to 147.15.255.254147.15.255.2558,190
129147.16.0.0/19147.16.0.1 to 147.16.31.254147.16.31.2558,190
130147.16.32.0/19147.16.32.1 to 147.16.63.254147.16.63.2558,190
131147.16.64.0/19147.16.64.1 to 147.16.95.254147.16.95.2558,190
132147.16.96.0/19147.16.96.1 to 147.16.127.254147.16.127.2558,190
133147.16.128.0/19147.16.128.1 to 147.16.159.254147.16.159.2558,190
134147.16.160.0/19147.16.160.1 to 147.16.191.254147.16.191.2558,190
135147.16.192.0/19147.16.192.1 to 147.16.223.254147.16.223.2558,190
136147.16.224.0/19147.16.224.1 to 147.16.255.254147.16.255.2558,190
137147.17.0.0/19147.17.0.1 to 147.17.31.254147.17.31.2558,190
138147.17.32.0/19147.17.32.1 to 147.17.63.254147.17.63.2558,190
139147.17.64.0/19147.17.64.1 to 147.17.95.254147.17.95.2558,190
140147.17.96.0/19147.17.96.1 to 147.17.127.254147.17.127.2558,190
141147.17.128.0/19147.17.128.1 to 147.17.159.254147.17.159.2558,190
142147.17.160.0/19147.17.160.1 to 147.17.191.254147.17.191.2558,190
143147.17.192.0/19147.17.192.1 to 147.17.223.254147.17.223.2558,190
144147.17.224.0/19147.17.224.1 to 147.17.255.254147.17.255.2558,190
145147.18.0.0/19147.18.0.1 to 147.18.31.254147.18.31.2558,190
146147.18.32.0/19147.18.32.1 to 147.18.63.254147.18.63.2558,190
147147.18.64.0/19147.18.64.1 to 147.18.95.254147.18.95.2558,190
148147.18.96.0/19147.18.96.1 to 147.18.127.254147.18.127.2558,190
149147.18.128.0/19147.18.128.1 to 147.18.159.254147.18.159.2558,190
150147.18.160.0/19147.18.160.1 to 147.18.191.254147.18.191.2558,190
151147.18.192.0/19147.18.192.1 to 147.18.223.254147.18.223.2558,190
152147.18.224.0/19147.18.224.1 to 147.18.255.254147.18.255.2558,190
153147.19.0.0/19147.19.0.1 to 147.19.31.254147.19.31.2558,190
154147.19.32.0/19147.19.32.1 to 147.19.63.254147.19.63.2558,190
155147.19.64.0/19147.19.64.1 to 147.19.95.254147.19.95.2558,190
156147.19.96.0/19147.19.96.1 to 147.19.127.254147.19.127.2558,190
157147.19.128.0/19147.19.128.1 to 147.19.159.254147.19.159.2558,190
158147.19.160.0/19147.19.160.1 to 147.19.191.254147.19.191.2558,190
159147.19.192.0/19147.19.192.1 to 147.19.223.254147.19.223.2558,190
160147.19.224.0/19147.19.224.1 to 147.19.255.254147.19.255.2558,190
161147.20.0.0/19147.20.0.1 to 147.20.31.254147.20.31.2558,190
162147.20.32.0/19147.20.32.1 to 147.20.63.254147.20.63.2558,190
163147.20.64.0/19147.20.64.1 to 147.20.95.254147.20.95.2558,190
164147.20.96.0/19147.20.96.1 to 147.20.127.254147.20.127.2558,190
165147.20.128.0/19147.20.128.1 to 147.20.159.254147.20.159.2558,190
166147.20.160.0/19147.20.160.1 to 147.20.191.254147.20.191.2558,190
167147.20.192.0/19147.20.192.1 to 147.20.223.254147.20.223.2558,190
168147.20.224.0/19147.20.224.1 to 147.20.255.254147.20.255.2558,190
169147.21.0.0/19147.21.0.1 to 147.21.31.254147.21.31.2558,190
170147.21.32.0/19147.21.32.1 to 147.21.63.254147.21.63.2558,190
171147.21.64.0/19147.21.64.1 to 147.21.95.254147.21.95.2558,190
172147.21.96.0/19147.21.96.1 to 147.21.127.254147.21.127.2558,190
173147.21.128.0/19147.21.128.1 to 147.21.159.254147.21.159.2558,190
174147.21.160.0/19147.21.160.1 to 147.21.191.254147.21.191.2558,190
175147.21.192.0/19147.21.192.1 to 147.21.223.254147.21.223.2558,190
176147.21.224.0/19147.21.224.1 to 147.21.255.254147.21.255.2558,190
177147.22.0.0/19147.22.0.1 to 147.22.31.254147.22.31.2558,190
178147.22.32.0/19147.22.32.1 to 147.22.63.254147.22.63.2558,190
179147.22.64.0/19147.22.64.1 to 147.22.95.254147.22.95.2558,190
180147.22.96.0/19147.22.96.1 to 147.22.127.254147.22.127.2558,190
181147.22.128.0/19147.22.128.1 to 147.22.159.254147.22.159.2558,190
182147.22.160.0/19147.22.160.1 to 147.22.191.254147.22.191.2558,190
183147.22.192.0/19147.22.192.1 to 147.22.223.254147.22.223.2558,190
184147.22.224.0/19147.22.224.1 to 147.22.255.254147.22.255.2558,190
185147.23.0.0/19147.23.0.1 to 147.23.31.254147.23.31.2558,190
186147.23.32.0/19147.23.32.1 to 147.23.63.254147.23.63.2558,190
187147.23.64.0/19147.23.64.1 to 147.23.95.254147.23.95.2558,190
188147.23.96.0/19147.23.96.1 to 147.23.127.254147.23.127.2558,190
189147.23.128.0/19147.23.128.1 to 147.23.159.254147.23.159.2558,190
190147.23.160.0/19147.23.160.1 to 147.23.191.254147.23.191.2558,190
191147.23.192.0/19147.23.192.1 to 147.23.223.254147.23.223.2558,190
192147.23.224.0/19147.23.224.1 to 147.23.255.254147.23.255.2558,190
193147.24.0.0/19147.24.0.1 to 147.24.31.254147.24.31.2558,190
194147.24.32.0/19147.24.32.1 to 147.24.63.254147.24.63.2558,190
195147.24.64.0/19147.24.64.1 to 147.24.95.254147.24.95.2558,190
196147.24.96.0/19147.24.96.1 to 147.24.127.254147.24.127.2558,190
197147.24.128.0/19147.24.128.1 to 147.24.159.254147.24.159.2558,190
198147.24.160.0/19147.24.160.1 to 147.24.191.254147.24.191.2558,190
199147.24.192.0/19147.24.192.1 to 147.24.223.254147.24.223.2558,190
200147.24.224.0/19147.24.224.1 to 147.24.255.254147.24.255.2558,190
201147.25.0.0/19147.25.0.1 to 147.25.31.254147.25.31.2558,190
202147.25.32.0/19147.25.32.1 to 147.25.63.254147.25.63.2558,190
203147.25.64.0/19147.25.64.1 to 147.25.95.254147.25.95.2558,190
204147.25.96.0/19147.25.96.1 to 147.25.127.254147.25.127.2558,190
205147.25.128.0/19147.25.128.1 to 147.25.159.254147.25.159.2558,190
206147.25.160.0/19147.25.160.1 to 147.25.191.254147.25.191.2558,190
207147.25.192.0/19147.25.192.1 to 147.25.223.254147.25.223.2558,190
208147.25.224.0/19147.25.224.1 to 147.25.255.254147.25.255.2558,190
209147.26.0.0/19147.26.0.1 to 147.26.31.254147.26.31.2558,190
210147.26.32.0/19147.26.32.1 to 147.26.63.254147.26.63.2558,190
211147.26.64.0/19147.26.64.1 to 147.26.95.254147.26.95.2558,190
212147.26.96.0/19147.26.96.1 to 147.26.127.254147.26.127.2558,190
213147.26.128.0/19147.26.128.1 to 147.26.159.254147.26.159.2558,190
214147.26.160.0/19147.26.160.1 to 147.26.191.254147.26.191.2558,190
215147.26.192.0/19147.26.192.1 to 147.26.223.254147.26.223.2558,190
216147.26.224.0/19147.26.224.1 to 147.26.255.254147.26.255.2558,190
217147.27.0.0/19147.27.0.1 to 147.27.31.254147.27.31.2558,190
218147.27.32.0/19147.27.32.1 to 147.27.63.254147.27.63.2558,190
219147.27.64.0/19147.27.64.1 to 147.27.95.254147.27.95.2558,190
220147.27.96.0/19147.27.96.1 to 147.27.127.254147.27.127.2558,190
221147.27.128.0/19147.27.128.1 to 147.27.159.254147.27.159.2558,190
222147.27.160.0/19147.27.160.1 to 147.27.191.254147.27.191.2558,190
223147.27.192.0/19147.27.192.1 to 147.27.223.254147.27.223.2558,190
224147.27.224.0/19147.27.224.1 to 147.27.255.254147.27.255.2558,190
225147.28.0.0/19147.28.0.1 to 147.28.31.254147.28.31.2558,190
226147.28.32.0/19147.28.32.1 to 147.28.63.254147.28.63.2558,190
227147.28.64.0/19147.28.64.1 to 147.28.95.254147.28.95.2558,190
228147.28.96.0/19147.28.96.1 to 147.28.127.254147.28.127.2558,190
229147.28.128.0/19147.28.128.1 to 147.28.159.254147.28.159.2558,190
230147.28.160.0/19147.28.160.1 to 147.28.191.254147.28.191.2558,190
231147.28.192.0/19147.28.192.1 to 147.28.223.254147.28.223.2558,190
232147.28.224.0/19147.28.224.1 to 147.28.255.254147.28.255.2558,190
233147.29.0.0/19147.29.0.1 to 147.29.31.254147.29.31.2558,190
234147.29.32.0/19147.29.32.1 to 147.29.63.254147.29.63.2558,190
235147.29.64.0/19147.29.64.1 to 147.29.95.254147.29.95.2558,190
236147.29.96.0/19147.29.96.1 to 147.29.127.254147.29.127.2558,190
237147.29.128.0/19147.29.128.1 to 147.29.159.254147.29.159.2558,190
238147.29.160.0/19147.29.160.1 to 147.29.191.254147.29.191.2558,190
239147.29.192.0/19147.29.192.1 to 147.29.223.254147.29.223.2558,190
240147.29.224.0/19147.29.224.1 to 147.29.255.254147.29.255.2558,190
241147.30.0.0/19147.30.0.1 to 147.30.31.254147.30.31.2558,190
242147.30.32.0/19147.30.32.1 to 147.30.63.254147.30.63.2558,190
243147.30.64.0/19147.30.64.1 to 147.30.95.254147.30.95.2558,190
244147.30.96.0/19147.30.96.1 to 147.30.127.254147.30.127.2558,190
245147.30.128.0/19147.30.128.1 to 147.30.159.254147.30.159.2558,190
246147.30.160.0/19147.30.160.1 to 147.30.191.254147.30.191.2558,190
247147.30.192.0/19147.30.192.1 to 147.30.223.254147.30.223.2558,190
248147.30.224.0/19147.30.224.1 to 147.30.255.254147.30.255.2558,190
249147.31.0.0/19147.31.0.1 to 147.31.31.254147.31.31.2558,190
250147.31.32.0/19147.31.32.1 to 147.31.63.254147.31.63.2558,190
251147.31.64.0/19147.31.64.1 to 147.31.95.254147.31.95.2558,190
252147.31.96.0/19147.31.96.1 to 147.31.127.254147.31.127.2558,190
253147.31.128.0/19147.31.128.1 to 147.31.159.254147.31.159.2558,190
254147.31.160.0/19147.31.160.1 to 147.31.191.254147.31.191.2558,190
255147.31.192.0/19147.31.192.1 to 147.31.223.254147.31.223.2558,190
256147.31.224.0/19147.31.224.1 to 147.31.255.254147.31.255.2558,190

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.