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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.

Network147.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
147.0.0.0
Broadcast address
147.255.255.255
First usable
147.0.0.1
Last usable
147.255.255.254
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 93000000 · Integer 2466250752 to 2483027967
Reverse DNS zone
147.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10010011..00000000.00000000.00000000147.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10010011..00000000.00000000.00000000147.0.0.0
Broadcast10010011..11111111.11111111.11111111147.255.255.255
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)

147.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1147.0.0.0/20147.0.0.1 to 147.0.15.254147.0.15.2554,094
2147.0.16.0/20147.0.16.1 to 147.0.31.254147.0.31.2554,094
3147.0.32.0/20147.0.32.1 to 147.0.47.254147.0.47.2554,094
4147.0.48.0/20147.0.48.1 to 147.0.63.254147.0.63.2554,094
5147.0.64.0/20147.0.64.1 to 147.0.79.254147.0.79.2554,094
6147.0.80.0/20147.0.80.1 to 147.0.95.254147.0.95.2554,094
7147.0.96.0/20147.0.96.1 to 147.0.111.254147.0.111.2554,094
8147.0.112.0/20147.0.112.1 to 147.0.127.254147.0.127.2554,094
9147.0.128.0/20147.0.128.1 to 147.0.143.254147.0.143.2554,094
10147.0.144.0/20147.0.144.1 to 147.0.159.254147.0.159.2554,094
11147.0.160.0/20147.0.160.1 to 147.0.175.254147.0.175.2554,094
12147.0.176.0/20147.0.176.1 to 147.0.191.254147.0.191.2554,094
13147.0.192.0/20147.0.192.1 to 147.0.207.254147.0.207.2554,094
14147.0.208.0/20147.0.208.1 to 147.0.223.254147.0.223.2554,094
15147.0.224.0/20147.0.224.1 to 147.0.239.254147.0.239.2554,094
16147.0.240.0/20147.0.240.1 to 147.0.255.254147.0.255.2554,094
17147.1.0.0/20147.1.0.1 to 147.1.15.254147.1.15.2554,094
18147.1.16.0/20147.1.16.1 to 147.1.31.254147.1.31.2554,094
19147.1.32.0/20147.1.32.1 to 147.1.47.254147.1.47.2554,094
20147.1.48.0/20147.1.48.1 to 147.1.63.254147.1.63.2554,094
21147.1.64.0/20147.1.64.1 to 147.1.79.254147.1.79.2554,094
22147.1.80.0/20147.1.80.1 to 147.1.95.254147.1.95.2554,094
23147.1.96.0/20147.1.96.1 to 147.1.111.254147.1.111.2554,094
24147.1.112.0/20147.1.112.1 to 147.1.127.254147.1.127.2554,094
25147.1.128.0/20147.1.128.1 to 147.1.143.254147.1.143.2554,094
26147.1.144.0/20147.1.144.1 to 147.1.159.254147.1.159.2554,094
27147.1.160.0/20147.1.160.1 to 147.1.175.254147.1.175.2554,094
28147.1.176.0/20147.1.176.1 to 147.1.191.254147.1.191.2554,094
29147.1.192.0/20147.1.192.1 to 147.1.207.254147.1.207.2554,094
30147.1.208.0/20147.1.208.1 to 147.1.223.254147.1.223.2554,094
31147.1.224.0/20147.1.224.1 to 147.1.239.254147.1.239.2554,094
32147.1.240.0/20147.1.240.1 to 147.1.255.254147.1.255.2554,094
33147.2.0.0/20147.2.0.1 to 147.2.15.254147.2.15.2554,094
34147.2.16.0/20147.2.16.1 to 147.2.31.254147.2.31.2554,094
35147.2.32.0/20147.2.32.1 to 147.2.47.254147.2.47.2554,094
36147.2.48.0/20147.2.48.1 to 147.2.63.254147.2.63.2554,094
37147.2.64.0/20147.2.64.1 to 147.2.79.254147.2.79.2554,094
38147.2.80.0/20147.2.80.1 to 147.2.95.254147.2.95.2554,094
39147.2.96.0/20147.2.96.1 to 147.2.111.254147.2.111.2554,094
40147.2.112.0/20147.2.112.1 to 147.2.127.254147.2.127.2554,094
41147.2.128.0/20147.2.128.1 to 147.2.143.254147.2.143.2554,094
42147.2.144.0/20147.2.144.1 to 147.2.159.254147.2.159.2554,094
43147.2.160.0/20147.2.160.1 to 147.2.175.254147.2.175.2554,094
44147.2.176.0/20147.2.176.1 to 147.2.191.254147.2.191.2554,094
45147.2.192.0/20147.2.192.1 to 147.2.207.254147.2.207.2554,094
46147.2.208.0/20147.2.208.1 to 147.2.223.254147.2.223.2554,094
47147.2.224.0/20147.2.224.1 to 147.2.239.254147.2.239.2554,094
48147.2.240.0/20147.2.240.1 to 147.2.255.254147.2.255.2554,094
49147.3.0.0/20147.3.0.1 to 147.3.15.254147.3.15.2554,094
50147.3.16.0/20147.3.16.1 to 147.3.31.254147.3.31.2554,094
51147.3.32.0/20147.3.32.1 to 147.3.47.254147.3.47.2554,094
52147.3.48.0/20147.3.48.1 to 147.3.63.254147.3.63.2554,094
53147.3.64.0/20147.3.64.1 to 147.3.79.254147.3.79.2554,094
54147.3.80.0/20147.3.80.1 to 147.3.95.254147.3.95.2554,094
55147.3.96.0/20147.3.96.1 to 147.3.111.254147.3.111.2554,094
56147.3.112.0/20147.3.112.1 to 147.3.127.254147.3.127.2554,094
57147.3.128.0/20147.3.128.1 to 147.3.143.254147.3.143.2554,094
58147.3.144.0/20147.3.144.1 to 147.3.159.254147.3.159.2554,094
59147.3.160.0/20147.3.160.1 to 147.3.175.254147.3.175.2554,094
60147.3.176.0/20147.3.176.1 to 147.3.191.254147.3.191.2554,094
61147.3.192.0/20147.3.192.1 to 147.3.207.254147.3.207.2554,094
62147.3.208.0/20147.3.208.1 to 147.3.223.254147.3.223.2554,094
63147.3.224.0/20147.3.224.1 to 147.3.239.254147.3.239.2554,094
64147.3.240.0/20147.3.240.1 to 147.3.255.254147.3.255.2554,094
65147.4.0.0/20147.4.0.1 to 147.4.15.254147.4.15.2554,094
66147.4.16.0/20147.4.16.1 to 147.4.31.254147.4.31.2554,094
67147.4.32.0/20147.4.32.1 to 147.4.47.254147.4.47.2554,094
68147.4.48.0/20147.4.48.1 to 147.4.63.254147.4.63.2554,094
69147.4.64.0/20147.4.64.1 to 147.4.79.254147.4.79.2554,094
70147.4.80.0/20147.4.80.1 to 147.4.95.254147.4.95.2554,094
71147.4.96.0/20147.4.96.1 to 147.4.111.254147.4.111.2554,094
72147.4.112.0/20147.4.112.1 to 147.4.127.254147.4.127.2554,094
73147.4.128.0/20147.4.128.1 to 147.4.143.254147.4.143.2554,094
74147.4.144.0/20147.4.144.1 to 147.4.159.254147.4.159.2554,094
75147.4.160.0/20147.4.160.1 to 147.4.175.254147.4.175.2554,094
76147.4.176.0/20147.4.176.1 to 147.4.191.254147.4.191.2554,094
77147.4.192.0/20147.4.192.1 to 147.4.207.254147.4.207.2554,094
78147.4.208.0/20147.4.208.1 to 147.4.223.254147.4.223.2554,094
79147.4.224.0/20147.4.224.1 to 147.4.239.254147.4.239.2554,094
80147.4.240.0/20147.4.240.1 to 147.4.255.254147.4.255.2554,094
81147.5.0.0/20147.5.0.1 to 147.5.15.254147.5.15.2554,094
82147.5.16.0/20147.5.16.1 to 147.5.31.254147.5.31.2554,094
83147.5.32.0/20147.5.32.1 to 147.5.47.254147.5.47.2554,094
84147.5.48.0/20147.5.48.1 to 147.5.63.254147.5.63.2554,094
85147.5.64.0/20147.5.64.1 to 147.5.79.254147.5.79.2554,094
86147.5.80.0/20147.5.80.1 to 147.5.95.254147.5.95.2554,094
87147.5.96.0/20147.5.96.1 to 147.5.111.254147.5.111.2554,094
88147.5.112.0/20147.5.112.1 to 147.5.127.254147.5.127.2554,094
89147.5.128.0/20147.5.128.1 to 147.5.143.254147.5.143.2554,094
90147.5.144.0/20147.5.144.1 to 147.5.159.254147.5.159.2554,094
91147.5.160.0/20147.5.160.1 to 147.5.175.254147.5.175.2554,094
92147.5.176.0/20147.5.176.1 to 147.5.191.254147.5.191.2554,094
93147.5.192.0/20147.5.192.1 to 147.5.207.254147.5.207.2554,094
94147.5.208.0/20147.5.208.1 to 147.5.223.254147.5.223.2554,094
95147.5.224.0/20147.5.224.1 to 147.5.239.254147.5.239.2554,094
96147.5.240.0/20147.5.240.1 to 147.5.255.254147.5.255.2554,094
97147.6.0.0/20147.6.0.1 to 147.6.15.254147.6.15.2554,094
98147.6.16.0/20147.6.16.1 to 147.6.31.254147.6.31.2554,094
99147.6.32.0/20147.6.32.1 to 147.6.47.254147.6.47.2554,094
100147.6.48.0/20147.6.48.1 to 147.6.63.254147.6.63.2554,094
101147.6.64.0/20147.6.64.1 to 147.6.79.254147.6.79.2554,094
102147.6.80.0/20147.6.80.1 to 147.6.95.254147.6.95.2554,094
103147.6.96.0/20147.6.96.1 to 147.6.111.254147.6.111.2554,094
104147.6.112.0/20147.6.112.1 to 147.6.127.254147.6.127.2554,094
105147.6.128.0/20147.6.128.1 to 147.6.143.254147.6.143.2554,094
106147.6.144.0/20147.6.144.1 to 147.6.159.254147.6.159.2554,094
107147.6.160.0/20147.6.160.1 to 147.6.175.254147.6.175.2554,094
108147.6.176.0/20147.6.176.1 to 147.6.191.254147.6.191.2554,094
109147.6.192.0/20147.6.192.1 to 147.6.207.254147.6.207.2554,094
110147.6.208.0/20147.6.208.1 to 147.6.223.254147.6.223.2554,094
111147.6.224.0/20147.6.224.1 to 147.6.239.254147.6.239.2554,094
112147.6.240.0/20147.6.240.1 to 147.6.255.254147.6.255.2554,094
113147.7.0.0/20147.7.0.1 to 147.7.15.254147.7.15.2554,094
114147.7.16.0/20147.7.16.1 to 147.7.31.254147.7.31.2554,094
115147.7.32.0/20147.7.32.1 to 147.7.47.254147.7.47.2554,094
116147.7.48.0/20147.7.48.1 to 147.7.63.254147.7.63.2554,094
117147.7.64.0/20147.7.64.1 to 147.7.79.254147.7.79.2554,094
118147.7.80.0/20147.7.80.1 to 147.7.95.254147.7.95.2554,094
119147.7.96.0/20147.7.96.1 to 147.7.111.254147.7.111.2554,094
120147.7.112.0/20147.7.112.1 to 147.7.127.254147.7.127.2554,094
121147.7.128.0/20147.7.128.1 to 147.7.143.254147.7.143.2554,094
122147.7.144.0/20147.7.144.1 to 147.7.159.254147.7.159.2554,094
123147.7.160.0/20147.7.160.1 to 147.7.175.254147.7.175.2554,094
124147.7.176.0/20147.7.176.1 to 147.7.191.254147.7.191.2554,094
125147.7.192.0/20147.7.192.1 to 147.7.207.254147.7.207.2554,094
126147.7.208.0/20147.7.208.1 to 147.7.223.254147.7.223.2554,094
127147.7.224.0/20147.7.224.1 to 147.7.239.254147.7.239.2554,094
128147.7.240.0/20147.7.240.1 to 147.7.255.254147.7.255.2554,094
129147.8.0.0/20147.8.0.1 to 147.8.15.254147.8.15.2554,094
130147.8.16.0/20147.8.16.1 to 147.8.31.254147.8.31.2554,094
131147.8.32.0/20147.8.32.1 to 147.8.47.254147.8.47.2554,094
132147.8.48.0/20147.8.48.1 to 147.8.63.254147.8.63.2554,094
133147.8.64.0/20147.8.64.1 to 147.8.79.254147.8.79.2554,094
134147.8.80.0/20147.8.80.1 to 147.8.95.254147.8.95.2554,094
135147.8.96.0/20147.8.96.1 to 147.8.111.254147.8.111.2554,094
136147.8.112.0/20147.8.112.1 to 147.8.127.254147.8.127.2554,094
137147.8.128.0/20147.8.128.1 to 147.8.143.254147.8.143.2554,094
138147.8.144.0/20147.8.144.1 to 147.8.159.254147.8.159.2554,094
139147.8.160.0/20147.8.160.1 to 147.8.175.254147.8.175.2554,094
140147.8.176.0/20147.8.176.1 to 147.8.191.254147.8.191.2554,094
141147.8.192.0/20147.8.192.1 to 147.8.207.254147.8.207.2554,094
142147.8.208.0/20147.8.208.1 to 147.8.223.254147.8.223.2554,094
143147.8.224.0/20147.8.224.1 to 147.8.239.254147.8.239.2554,094
144147.8.240.0/20147.8.240.1 to 147.8.255.254147.8.255.2554,094
145147.9.0.0/20147.9.0.1 to 147.9.15.254147.9.15.2554,094
146147.9.16.0/20147.9.16.1 to 147.9.31.254147.9.31.2554,094
147147.9.32.0/20147.9.32.1 to 147.9.47.254147.9.47.2554,094
148147.9.48.0/20147.9.48.1 to 147.9.63.254147.9.63.2554,094
149147.9.64.0/20147.9.64.1 to 147.9.79.254147.9.79.2554,094
150147.9.80.0/20147.9.80.1 to 147.9.95.254147.9.95.2554,094
151147.9.96.0/20147.9.96.1 to 147.9.111.254147.9.111.2554,094
152147.9.112.0/20147.9.112.1 to 147.9.127.254147.9.127.2554,094
153147.9.128.0/20147.9.128.1 to 147.9.143.254147.9.143.2554,094
154147.9.144.0/20147.9.144.1 to 147.9.159.254147.9.159.2554,094
155147.9.160.0/20147.9.160.1 to 147.9.175.254147.9.175.2554,094
156147.9.176.0/20147.9.176.1 to 147.9.191.254147.9.191.2554,094
157147.9.192.0/20147.9.192.1 to 147.9.207.254147.9.207.2554,094
158147.9.208.0/20147.9.208.1 to 147.9.223.254147.9.223.2554,094
159147.9.224.0/20147.9.224.1 to 147.9.239.254147.9.239.2554,094
160147.9.240.0/20147.9.240.1 to 147.9.255.254147.9.255.2554,094
161147.10.0.0/20147.10.0.1 to 147.10.15.254147.10.15.2554,094
162147.10.16.0/20147.10.16.1 to 147.10.31.254147.10.31.2554,094
163147.10.32.0/20147.10.32.1 to 147.10.47.254147.10.47.2554,094
164147.10.48.0/20147.10.48.1 to 147.10.63.254147.10.63.2554,094
165147.10.64.0/20147.10.64.1 to 147.10.79.254147.10.79.2554,094
166147.10.80.0/20147.10.80.1 to 147.10.95.254147.10.95.2554,094
167147.10.96.0/20147.10.96.1 to 147.10.111.254147.10.111.2554,094
168147.10.112.0/20147.10.112.1 to 147.10.127.254147.10.127.2554,094
169147.10.128.0/20147.10.128.1 to 147.10.143.254147.10.143.2554,094
170147.10.144.0/20147.10.144.1 to 147.10.159.254147.10.159.2554,094
171147.10.160.0/20147.10.160.1 to 147.10.175.254147.10.175.2554,094
172147.10.176.0/20147.10.176.1 to 147.10.191.254147.10.191.2554,094
173147.10.192.0/20147.10.192.1 to 147.10.207.254147.10.207.2554,094
174147.10.208.0/20147.10.208.1 to 147.10.223.254147.10.223.2554,094
175147.10.224.0/20147.10.224.1 to 147.10.239.254147.10.239.2554,094
176147.10.240.0/20147.10.240.1 to 147.10.255.254147.10.255.2554,094
177147.11.0.0/20147.11.0.1 to 147.11.15.254147.11.15.2554,094
178147.11.16.0/20147.11.16.1 to 147.11.31.254147.11.31.2554,094
179147.11.32.0/20147.11.32.1 to 147.11.47.254147.11.47.2554,094
180147.11.48.0/20147.11.48.1 to 147.11.63.254147.11.63.2554,094
181147.11.64.0/20147.11.64.1 to 147.11.79.254147.11.79.2554,094
182147.11.80.0/20147.11.80.1 to 147.11.95.254147.11.95.2554,094
183147.11.96.0/20147.11.96.1 to 147.11.111.254147.11.111.2554,094
184147.11.112.0/20147.11.112.1 to 147.11.127.254147.11.127.2554,094
185147.11.128.0/20147.11.128.1 to 147.11.143.254147.11.143.2554,094
186147.11.144.0/20147.11.144.1 to 147.11.159.254147.11.159.2554,094
187147.11.160.0/20147.11.160.1 to 147.11.175.254147.11.175.2554,094
188147.11.176.0/20147.11.176.1 to 147.11.191.254147.11.191.2554,094
189147.11.192.0/20147.11.192.1 to 147.11.207.254147.11.207.2554,094
190147.11.208.0/20147.11.208.1 to 147.11.223.254147.11.223.2554,094
191147.11.224.0/20147.11.224.1 to 147.11.239.254147.11.239.2554,094
192147.11.240.0/20147.11.240.1 to 147.11.255.254147.11.255.2554,094
193147.12.0.0/20147.12.0.1 to 147.12.15.254147.12.15.2554,094
194147.12.16.0/20147.12.16.1 to 147.12.31.254147.12.31.2554,094
195147.12.32.0/20147.12.32.1 to 147.12.47.254147.12.47.2554,094
196147.12.48.0/20147.12.48.1 to 147.12.63.254147.12.63.2554,094
197147.12.64.0/20147.12.64.1 to 147.12.79.254147.12.79.2554,094
198147.12.80.0/20147.12.80.1 to 147.12.95.254147.12.95.2554,094
199147.12.96.0/20147.12.96.1 to 147.12.111.254147.12.111.2554,094
200147.12.112.0/20147.12.112.1 to 147.12.127.254147.12.127.2554,094
201147.12.128.0/20147.12.128.1 to 147.12.143.254147.12.143.2554,094
202147.12.144.0/20147.12.144.1 to 147.12.159.254147.12.159.2554,094
203147.12.160.0/20147.12.160.1 to 147.12.175.254147.12.175.2554,094
204147.12.176.0/20147.12.176.1 to 147.12.191.254147.12.191.2554,094
205147.12.192.0/20147.12.192.1 to 147.12.207.254147.12.207.2554,094
206147.12.208.0/20147.12.208.1 to 147.12.223.254147.12.223.2554,094
207147.12.224.0/20147.12.224.1 to 147.12.239.254147.12.239.2554,094
208147.12.240.0/20147.12.240.1 to 147.12.255.254147.12.255.2554,094
209147.13.0.0/20147.13.0.1 to 147.13.15.254147.13.15.2554,094
210147.13.16.0/20147.13.16.1 to 147.13.31.254147.13.31.2554,094
211147.13.32.0/20147.13.32.1 to 147.13.47.254147.13.47.2554,094
212147.13.48.0/20147.13.48.1 to 147.13.63.254147.13.63.2554,094
213147.13.64.0/20147.13.64.1 to 147.13.79.254147.13.79.2554,094
214147.13.80.0/20147.13.80.1 to 147.13.95.254147.13.95.2554,094
215147.13.96.0/20147.13.96.1 to 147.13.111.254147.13.111.2554,094
216147.13.112.0/20147.13.112.1 to 147.13.127.254147.13.127.2554,094
217147.13.128.0/20147.13.128.1 to 147.13.143.254147.13.143.2554,094
218147.13.144.0/20147.13.144.1 to 147.13.159.254147.13.159.2554,094
219147.13.160.0/20147.13.160.1 to 147.13.175.254147.13.175.2554,094
220147.13.176.0/20147.13.176.1 to 147.13.191.254147.13.191.2554,094
221147.13.192.0/20147.13.192.1 to 147.13.207.254147.13.207.2554,094
222147.13.208.0/20147.13.208.1 to 147.13.223.254147.13.223.2554,094
223147.13.224.0/20147.13.224.1 to 147.13.239.254147.13.239.2554,094
224147.13.240.0/20147.13.240.1 to 147.13.255.254147.13.255.2554,094
225147.14.0.0/20147.14.0.1 to 147.14.15.254147.14.15.2554,094
226147.14.16.0/20147.14.16.1 to 147.14.31.254147.14.31.2554,094
227147.14.32.0/20147.14.32.1 to 147.14.47.254147.14.47.2554,094
228147.14.48.0/20147.14.48.1 to 147.14.63.254147.14.63.2554,094
229147.14.64.0/20147.14.64.1 to 147.14.79.254147.14.79.2554,094
230147.14.80.0/20147.14.80.1 to 147.14.95.254147.14.95.2554,094
231147.14.96.0/20147.14.96.1 to 147.14.111.254147.14.111.2554,094
232147.14.112.0/20147.14.112.1 to 147.14.127.254147.14.127.2554,094
233147.14.128.0/20147.14.128.1 to 147.14.143.254147.14.143.2554,094
234147.14.144.0/20147.14.144.1 to 147.14.159.254147.14.159.2554,094
235147.14.160.0/20147.14.160.1 to 147.14.175.254147.14.175.2554,094
236147.14.176.0/20147.14.176.1 to 147.14.191.254147.14.191.2554,094
237147.14.192.0/20147.14.192.1 to 147.14.207.254147.14.207.2554,094
238147.14.208.0/20147.14.208.1 to 147.14.223.254147.14.223.2554,094
239147.14.224.0/20147.14.224.1 to 147.14.239.254147.14.239.2554,094
240147.14.240.0/20147.14.240.1 to 147.14.255.254147.14.255.2554,094
241147.15.0.0/20147.15.0.1 to 147.15.15.254147.15.15.2554,094
242147.15.16.0/20147.15.16.1 to 147.15.31.254147.15.31.2554,094
243147.15.32.0/20147.15.32.1 to 147.15.47.254147.15.47.2554,094
244147.15.48.0/20147.15.48.1 to 147.15.63.254147.15.63.2554,094
245147.15.64.0/20147.15.64.1 to 147.15.79.254147.15.79.2554,094
246147.15.80.0/20147.15.80.1 to 147.15.95.254147.15.95.2554,094
247147.15.96.0/20147.15.96.1 to 147.15.111.254147.15.111.2554,094
248147.15.112.0/20147.15.112.1 to 147.15.127.254147.15.127.2554,094
249147.15.128.0/20147.15.128.1 to 147.15.143.254147.15.143.2554,094
250147.15.144.0/20147.15.144.1 to 147.15.159.254147.15.159.2554,094
251147.15.160.0/20147.15.160.1 to 147.15.175.254147.15.175.2554,094
252147.15.176.0/20147.15.176.1 to 147.15.191.254147.15.191.2554,094
253147.15.192.0/20147.15.192.1 to 147.15.207.254147.15.207.2554,094
254147.15.208.0/20147.15.208.1 to 147.15.223.254147.15.223.2554,094
255147.15.224.0/20147.15.224.1 to 147.15.239.254147.15.239.2554,094
256147.15.240.0/20147.15.240.1 to 147.15.255.254147.15.255.2554,094

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.