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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.

Network148.158.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
148.158.0.0
Broadcast address
148.158.255.255
First usable
148.158.0.1
Last usable
148.158.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
B (default /16)
As numbers
Hex 949E0000 · Integer 2493382656 to 2493448191
Reverse DNS zone
158.148.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10010100.10011110..00000000.00000000148.158.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network10010100.10011110..00000000.00000000148.158.0.0
Broadcast10010100.10011110..11111111.11111111148.158.255.255
Split into smaller subnets/28

148.158.0.0/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1148.158.0.0/28148.158.0.1 to 148.158.0.14148.158.0.1514
2148.158.0.16/28148.158.0.17 to 148.158.0.30148.158.0.3114
3148.158.0.32/28148.158.0.33 to 148.158.0.46148.158.0.4714
4148.158.0.48/28148.158.0.49 to 148.158.0.62148.158.0.6314
5148.158.0.64/28148.158.0.65 to 148.158.0.78148.158.0.7914
6148.158.0.80/28148.158.0.81 to 148.158.0.94148.158.0.9514
7148.158.0.96/28148.158.0.97 to 148.158.0.110148.158.0.11114
8148.158.0.112/28148.158.0.113 to 148.158.0.126148.158.0.12714
9148.158.0.128/28148.158.0.129 to 148.158.0.142148.158.0.14314
10148.158.0.144/28148.158.0.145 to 148.158.0.158148.158.0.15914
11148.158.0.160/28148.158.0.161 to 148.158.0.174148.158.0.17514
12148.158.0.176/28148.158.0.177 to 148.158.0.190148.158.0.19114
13148.158.0.192/28148.158.0.193 to 148.158.0.206148.158.0.20714
14148.158.0.208/28148.158.0.209 to 148.158.0.222148.158.0.22314
15148.158.0.224/28148.158.0.225 to 148.158.0.238148.158.0.23914
16148.158.0.240/28148.158.0.241 to 148.158.0.254148.158.0.25514
17148.158.1.0/28148.158.1.1 to 148.158.1.14148.158.1.1514
18148.158.1.16/28148.158.1.17 to 148.158.1.30148.158.1.3114
19148.158.1.32/28148.158.1.33 to 148.158.1.46148.158.1.4714
20148.158.1.48/28148.158.1.49 to 148.158.1.62148.158.1.6314
21148.158.1.64/28148.158.1.65 to 148.158.1.78148.158.1.7914
22148.158.1.80/28148.158.1.81 to 148.158.1.94148.158.1.9514
23148.158.1.96/28148.158.1.97 to 148.158.1.110148.158.1.11114
24148.158.1.112/28148.158.1.113 to 148.158.1.126148.158.1.12714
25148.158.1.128/28148.158.1.129 to 148.158.1.142148.158.1.14314
26148.158.1.144/28148.158.1.145 to 148.158.1.158148.158.1.15914
27148.158.1.160/28148.158.1.161 to 148.158.1.174148.158.1.17514
28148.158.1.176/28148.158.1.177 to 148.158.1.190148.158.1.19114
29148.158.1.192/28148.158.1.193 to 148.158.1.206148.158.1.20714
30148.158.1.208/28148.158.1.209 to 148.158.1.222148.158.1.22314
31148.158.1.224/28148.158.1.225 to 148.158.1.238148.158.1.23914
32148.158.1.240/28148.158.1.241 to 148.158.1.254148.158.1.25514
33148.158.2.0/28148.158.2.1 to 148.158.2.14148.158.2.1514
34148.158.2.16/28148.158.2.17 to 148.158.2.30148.158.2.3114
35148.158.2.32/28148.158.2.33 to 148.158.2.46148.158.2.4714
36148.158.2.48/28148.158.2.49 to 148.158.2.62148.158.2.6314
37148.158.2.64/28148.158.2.65 to 148.158.2.78148.158.2.7914
38148.158.2.80/28148.158.2.81 to 148.158.2.94148.158.2.9514
39148.158.2.96/28148.158.2.97 to 148.158.2.110148.158.2.11114
40148.158.2.112/28148.158.2.113 to 148.158.2.126148.158.2.12714
41148.158.2.128/28148.158.2.129 to 148.158.2.142148.158.2.14314
42148.158.2.144/28148.158.2.145 to 148.158.2.158148.158.2.15914
43148.158.2.160/28148.158.2.161 to 148.158.2.174148.158.2.17514
44148.158.2.176/28148.158.2.177 to 148.158.2.190148.158.2.19114
45148.158.2.192/28148.158.2.193 to 148.158.2.206148.158.2.20714
46148.158.2.208/28148.158.2.209 to 148.158.2.222148.158.2.22314
47148.158.2.224/28148.158.2.225 to 148.158.2.238148.158.2.23914
48148.158.2.240/28148.158.2.241 to 148.158.2.254148.158.2.25514
49148.158.3.0/28148.158.3.1 to 148.158.3.14148.158.3.1514
50148.158.3.16/28148.158.3.17 to 148.158.3.30148.158.3.3114
51148.158.3.32/28148.158.3.33 to 148.158.3.46148.158.3.4714
52148.158.3.48/28148.158.3.49 to 148.158.3.62148.158.3.6314
53148.158.3.64/28148.158.3.65 to 148.158.3.78148.158.3.7914
54148.158.3.80/28148.158.3.81 to 148.158.3.94148.158.3.9514
55148.158.3.96/28148.158.3.97 to 148.158.3.110148.158.3.11114
56148.158.3.112/28148.158.3.113 to 148.158.3.126148.158.3.12714
57148.158.3.128/28148.158.3.129 to 148.158.3.142148.158.3.14314
58148.158.3.144/28148.158.3.145 to 148.158.3.158148.158.3.15914
59148.158.3.160/28148.158.3.161 to 148.158.3.174148.158.3.17514
60148.158.3.176/28148.158.3.177 to 148.158.3.190148.158.3.19114
61148.158.3.192/28148.158.3.193 to 148.158.3.206148.158.3.20714
62148.158.3.208/28148.158.3.209 to 148.158.3.222148.158.3.22314
63148.158.3.224/28148.158.3.225 to 148.158.3.238148.158.3.23914
64148.158.3.240/28148.158.3.241 to 148.158.3.254148.158.3.25514
65148.158.4.0/28148.158.4.1 to 148.158.4.14148.158.4.1514
66148.158.4.16/28148.158.4.17 to 148.158.4.30148.158.4.3114
67148.158.4.32/28148.158.4.33 to 148.158.4.46148.158.4.4714
68148.158.4.48/28148.158.4.49 to 148.158.4.62148.158.4.6314
69148.158.4.64/28148.158.4.65 to 148.158.4.78148.158.4.7914
70148.158.4.80/28148.158.4.81 to 148.158.4.94148.158.4.9514
71148.158.4.96/28148.158.4.97 to 148.158.4.110148.158.4.11114
72148.158.4.112/28148.158.4.113 to 148.158.4.126148.158.4.12714
73148.158.4.128/28148.158.4.129 to 148.158.4.142148.158.4.14314
74148.158.4.144/28148.158.4.145 to 148.158.4.158148.158.4.15914
75148.158.4.160/28148.158.4.161 to 148.158.4.174148.158.4.17514
76148.158.4.176/28148.158.4.177 to 148.158.4.190148.158.4.19114
77148.158.4.192/28148.158.4.193 to 148.158.4.206148.158.4.20714
78148.158.4.208/28148.158.4.209 to 148.158.4.222148.158.4.22314
79148.158.4.224/28148.158.4.225 to 148.158.4.238148.158.4.23914
80148.158.4.240/28148.158.4.241 to 148.158.4.254148.158.4.25514
81148.158.5.0/28148.158.5.1 to 148.158.5.14148.158.5.1514
82148.158.5.16/28148.158.5.17 to 148.158.5.30148.158.5.3114
83148.158.5.32/28148.158.5.33 to 148.158.5.46148.158.5.4714
84148.158.5.48/28148.158.5.49 to 148.158.5.62148.158.5.6314
85148.158.5.64/28148.158.5.65 to 148.158.5.78148.158.5.7914
86148.158.5.80/28148.158.5.81 to 148.158.5.94148.158.5.9514
87148.158.5.96/28148.158.5.97 to 148.158.5.110148.158.5.11114
88148.158.5.112/28148.158.5.113 to 148.158.5.126148.158.5.12714
89148.158.5.128/28148.158.5.129 to 148.158.5.142148.158.5.14314
90148.158.5.144/28148.158.5.145 to 148.158.5.158148.158.5.15914
91148.158.5.160/28148.158.5.161 to 148.158.5.174148.158.5.17514
92148.158.5.176/28148.158.5.177 to 148.158.5.190148.158.5.19114
93148.158.5.192/28148.158.5.193 to 148.158.5.206148.158.5.20714
94148.158.5.208/28148.158.5.209 to 148.158.5.222148.158.5.22314
95148.158.5.224/28148.158.5.225 to 148.158.5.238148.158.5.23914
96148.158.5.240/28148.158.5.241 to 148.158.5.254148.158.5.25514
97148.158.6.0/28148.158.6.1 to 148.158.6.14148.158.6.1514
98148.158.6.16/28148.158.6.17 to 148.158.6.30148.158.6.3114
99148.158.6.32/28148.158.6.33 to 148.158.6.46148.158.6.4714
100148.158.6.48/28148.158.6.49 to 148.158.6.62148.158.6.6314
101148.158.6.64/28148.158.6.65 to 148.158.6.78148.158.6.7914
102148.158.6.80/28148.158.6.81 to 148.158.6.94148.158.6.9514
103148.158.6.96/28148.158.6.97 to 148.158.6.110148.158.6.11114
104148.158.6.112/28148.158.6.113 to 148.158.6.126148.158.6.12714
105148.158.6.128/28148.158.6.129 to 148.158.6.142148.158.6.14314
106148.158.6.144/28148.158.6.145 to 148.158.6.158148.158.6.15914
107148.158.6.160/28148.158.6.161 to 148.158.6.174148.158.6.17514
108148.158.6.176/28148.158.6.177 to 148.158.6.190148.158.6.19114
109148.158.6.192/28148.158.6.193 to 148.158.6.206148.158.6.20714
110148.158.6.208/28148.158.6.209 to 148.158.6.222148.158.6.22314
111148.158.6.224/28148.158.6.225 to 148.158.6.238148.158.6.23914
112148.158.6.240/28148.158.6.241 to 148.158.6.254148.158.6.25514
113148.158.7.0/28148.158.7.1 to 148.158.7.14148.158.7.1514
114148.158.7.16/28148.158.7.17 to 148.158.7.30148.158.7.3114
115148.158.7.32/28148.158.7.33 to 148.158.7.46148.158.7.4714
116148.158.7.48/28148.158.7.49 to 148.158.7.62148.158.7.6314
117148.158.7.64/28148.158.7.65 to 148.158.7.78148.158.7.7914
118148.158.7.80/28148.158.7.81 to 148.158.7.94148.158.7.9514
119148.158.7.96/28148.158.7.97 to 148.158.7.110148.158.7.11114
120148.158.7.112/28148.158.7.113 to 148.158.7.126148.158.7.12714
121148.158.7.128/28148.158.7.129 to 148.158.7.142148.158.7.14314
122148.158.7.144/28148.158.7.145 to 148.158.7.158148.158.7.15914
123148.158.7.160/28148.158.7.161 to 148.158.7.174148.158.7.17514
124148.158.7.176/28148.158.7.177 to 148.158.7.190148.158.7.19114
125148.158.7.192/28148.158.7.193 to 148.158.7.206148.158.7.20714
126148.158.7.208/28148.158.7.209 to 148.158.7.222148.158.7.22314
127148.158.7.224/28148.158.7.225 to 148.158.7.238148.158.7.23914
128148.158.7.240/28148.158.7.241 to 148.158.7.254148.158.7.25514
129148.158.8.0/28148.158.8.1 to 148.158.8.14148.158.8.1514
130148.158.8.16/28148.158.8.17 to 148.158.8.30148.158.8.3114
131148.158.8.32/28148.158.8.33 to 148.158.8.46148.158.8.4714
132148.158.8.48/28148.158.8.49 to 148.158.8.62148.158.8.6314
133148.158.8.64/28148.158.8.65 to 148.158.8.78148.158.8.7914
134148.158.8.80/28148.158.8.81 to 148.158.8.94148.158.8.9514
135148.158.8.96/28148.158.8.97 to 148.158.8.110148.158.8.11114
136148.158.8.112/28148.158.8.113 to 148.158.8.126148.158.8.12714
137148.158.8.128/28148.158.8.129 to 148.158.8.142148.158.8.14314
138148.158.8.144/28148.158.8.145 to 148.158.8.158148.158.8.15914
139148.158.8.160/28148.158.8.161 to 148.158.8.174148.158.8.17514
140148.158.8.176/28148.158.8.177 to 148.158.8.190148.158.8.19114
141148.158.8.192/28148.158.8.193 to 148.158.8.206148.158.8.20714
142148.158.8.208/28148.158.8.209 to 148.158.8.222148.158.8.22314
143148.158.8.224/28148.158.8.225 to 148.158.8.238148.158.8.23914
144148.158.8.240/28148.158.8.241 to 148.158.8.254148.158.8.25514
145148.158.9.0/28148.158.9.1 to 148.158.9.14148.158.9.1514
146148.158.9.16/28148.158.9.17 to 148.158.9.30148.158.9.3114
147148.158.9.32/28148.158.9.33 to 148.158.9.46148.158.9.4714
148148.158.9.48/28148.158.9.49 to 148.158.9.62148.158.9.6314
149148.158.9.64/28148.158.9.65 to 148.158.9.78148.158.9.7914
150148.158.9.80/28148.158.9.81 to 148.158.9.94148.158.9.9514
151148.158.9.96/28148.158.9.97 to 148.158.9.110148.158.9.11114
152148.158.9.112/28148.158.9.113 to 148.158.9.126148.158.9.12714
153148.158.9.128/28148.158.9.129 to 148.158.9.142148.158.9.14314
154148.158.9.144/28148.158.9.145 to 148.158.9.158148.158.9.15914
155148.158.9.160/28148.158.9.161 to 148.158.9.174148.158.9.17514
156148.158.9.176/28148.158.9.177 to 148.158.9.190148.158.9.19114
157148.158.9.192/28148.158.9.193 to 148.158.9.206148.158.9.20714
158148.158.9.208/28148.158.9.209 to 148.158.9.222148.158.9.22314
159148.158.9.224/28148.158.9.225 to 148.158.9.238148.158.9.23914
160148.158.9.240/28148.158.9.241 to 148.158.9.254148.158.9.25514
161148.158.10.0/28148.158.10.1 to 148.158.10.14148.158.10.1514
162148.158.10.16/28148.158.10.17 to 148.158.10.30148.158.10.3114
163148.158.10.32/28148.158.10.33 to 148.158.10.46148.158.10.4714
164148.158.10.48/28148.158.10.49 to 148.158.10.62148.158.10.6314
165148.158.10.64/28148.158.10.65 to 148.158.10.78148.158.10.7914
166148.158.10.80/28148.158.10.81 to 148.158.10.94148.158.10.9514
167148.158.10.96/28148.158.10.97 to 148.158.10.110148.158.10.11114
168148.158.10.112/28148.158.10.113 to 148.158.10.126148.158.10.12714
169148.158.10.128/28148.158.10.129 to 148.158.10.142148.158.10.14314
170148.158.10.144/28148.158.10.145 to 148.158.10.158148.158.10.15914
171148.158.10.160/28148.158.10.161 to 148.158.10.174148.158.10.17514
172148.158.10.176/28148.158.10.177 to 148.158.10.190148.158.10.19114
173148.158.10.192/28148.158.10.193 to 148.158.10.206148.158.10.20714
174148.158.10.208/28148.158.10.209 to 148.158.10.222148.158.10.22314
175148.158.10.224/28148.158.10.225 to 148.158.10.238148.158.10.23914
176148.158.10.240/28148.158.10.241 to 148.158.10.254148.158.10.25514
177148.158.11.0/28148.158.11.1 to 148.158.11.14148.158.11.1514
178148.158.11.16/28148.158.11.17 to 148.158.11.30148.158.11.3114
179148.158.11.32/28148.158.11.33 to 148.158.11.46148.158.11.4714
180148.158.11.48/28148.158.11.49 to 148.158.11.62148.158.11.6314
181148.158.11.64/28148.158.11.65 to 148.158.11.78148.158.11.7914
182148.158.11.80/28148.158.11.81 to 148.158.11.94148.158.11.9514
183148.158.11.96/28148.158.11.97 to 148.158.11.110148.158.11.11114
184148.158.11.112/28148.158.11.113 to 148.158.11.126148.158.11.12714
185148.158.11.128/28148.158.11.129 to 148.158.11.142148.158.11.14314
186148.158.11.144/28148.158.11.145 to 148.158.11.158148.158.11.15914
187148.158.11.160/28148.158.11.161 to 148.158.11.174148.158.11.17514
188148.158.11.176/28148.158.11.177 to 148.158.11.190148.158.11.19114
189148.158.11.192/28148.158.11.193 to 148.158.11.206148.158.11.20714
190148.158.11.208/28148.158.11.209 to 148.158.11.222148.158.11.22314
191148.158.11.224/28148.158.11.225 to 148.158.11.238148.158.11.23914
192148.158.11.240/28148.158.11.241 to 148.158.11.254148.158.11.25514
193148.158.12.0/28148.158.12.1 to 148.158.12.14148.158.12.1514
194148.158.12.16/28148.158.12.17 to 148.158.12.30148.158.12.3114
195148.158.12.32/28148.158.12.33 to 148.158.12.46148.158.12.4714
196148.158.12.48/28148.158.12.49 to 148.158.12.62148.158.12.6314
197148.158.12.64/28148.158.12.65 to 148.158.12.78148.158.12.7914
198148.158.12.80/28148.158.12.81 to 148.158.12.94148.158.12.9514
199148.158.12.96/28148.158.12.97 to 148.158.12.110148.158.12.11114
200148.158.12.112/28148.158.12.113 to 148.158.12.126148.158.12.12714
201148.158.12.128/28148.158.12.129 to 148.158.12.142148.158.12.14314
202148.158.12.144/28148.158.12.145 to 148.158.12.158148.158.12.15914
203148.158.12.160/28148.158.12.161 to 148.158.12.174148.158.12.17514
204148.158.12.176/28148.158.12.177 to 148.158.12.190148.158.12.19114
205148.158.12.192/28148.158.12.193 to 148.158.12.206148.158.12.20714
206148.158.12.208/28148.158.12.209 to 148.158.12.222148.158.12.22314
207148.158.12.224/28148.158.12.225 to 148.158.12.238148.158.12.23914
208148.158.12.240/28148.158.12.241 to 148.158.12.254148.158.12.25514
209148.158.13.0/28148.158.13.1 to 148.158.13.14148.158.13.1514
210148.158.13.16/28148.158.13.17 to 148.158.13.30148.158.13.3114
211148.158.13.32/28148.158.13.33 to 148.158.13.46148.158.13.4714
212148.158.13.48/28148.158.13.49 to 148.158.13.62148.158.13.6314
213148.158.13.64/28148.158.13.65 to 148.158.13.78148.158.13.7914
214148.158.13.80/28148.158.13.81 to 148.158.13.94148.158.13.9514
215148.158.13.96/28148.158.13.97 to 148.158.13.110148.158.13.11114
216148.158.13.112/28148.158.13.113 to 148.158.13.126148.158.13.12714
217148.158.13.128/28148.158.13.129 to 148.158.13.142148.158.13.14314
218148.158.13.144/28148.158.13.145 to 148.158.13.158148.158.13.15914
219148.158.13.160/28148.158.13.161 to 148.158.13.174148.158.13.17514
220148.158.13.176/28148.158.13.177 to 148.158.13.190148.158.13.19114
221148.158.13.192/28148.158.13.193 to 148.158.13.206148.158.13.20714
222148.158.13.208/28148.158.13.209 to 148.158.13.222148.158.13.22314
223148.158.13.224/28148.158.13.225 to 148.158.13.238148.158.13.23914
224148.158.13.240/28148.158.13.241 to 148.158.13.254148.158.13.25514
225148.158.14.0/28148.158.14.1 to 148.158.14.14148.158.14.1514
226148.158.14.16/28148.158.14.17 to 148.158.14.30148.158.14.3114
227148.158.14.32/28148.158.14.33 to 148.158.14.46148.158.14.4714
228148.158.14.48/28148.158.14.49 to 148.158.14.62148.158.14.6314
229148.158.14.64/28148.158.14.65 to 148.158.14.78148.158.14.7914
230148.158.14.80/28148.158.14.81 to 148.158.14.94148.158.14.9514
231148.158.14.96/28148.158.14.97 to 148.158.14.110148.158.14.11114
232148.158.14.112/28148.158.14.113 to 148.158.14.126148.158.14.12714
233148.158.14.128/28148.158.14.129 to 148.158.14.142148.158.14.14314
234148.158.14.144/28148.158.14.145 to 148.158.14.158148.158.14.15914
235148.158.14.160/28148.158.14.161 to 148.158.14.174148.158.14.17514
236148.158.14.176/28148.158.14.177 to 148.158.14.190148.158.14.19114
237148.158.14.192/28148.158.14.193 to 148.158.14.206148.158.14.20714
238148.158.14.208/28148.158.14.209 to 148.158.14.222148.158.14.22314
239148.158.14.224/28148.158.14.225 to 148.158.14.238148.158.14.23914
240148.158.14.240/28148.158.14.241 to 148.158.14.254148.158.14.25514
241148.158.15.0/28148.158.15.1 to 148.158.15.14148.158.15.1514
242148.158.15.16/28148.158.15.17 to 148.158.15.30148.158.15.3114
243148.158.15.32/28148.158.15.33 to 148.158.15.46148.158.15.4714
244148.158.15.48/28148.158.15.49 to 148.158.15.62148.158.15.6314
245148.158.15.64/28148.158.15.65 to 148.158.15.78148.158.15.7914
246148.158.15.80/28148.158.15.81 to 148.158.15.94148.158.15.9514
247148.158.15.96/28148.158.15.97 to 148.158.15.110148.158.15.11114
248148.158.15.112/28148.158.15.113 to 148.158.15.126148.158.15.12714
249148.158.15.128/28148.158.15.129 to 148.158.15.142148.158.15.14314
250148.158.15.144/28148.158.15.145 to 148.158.15.158148.158.15.15914
251148.158.15.160/28148.158.15.161 to 148.158.15.174148.158.15.17514
252148.158.15.176/28148.158.15.177 to 148.158.15.190148.158.15.19114
253148.158.15.192/28148.158.15.193 to 148.158.15.206148.158.15.20714
254148.158.15.208/28148.158.15.209 to 148.158.15.222148.158.15.22314
255148.158.15.224/28148.158.15.225 to 148.158.15.238148.158.15.23914
256148.158.15.240/28148.158.15.241 to 148.158.15.254148.158.15.25514

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