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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.

Network111.28.0.0/18
Usable hosts16,382
Subnet mask255.255.192.0
Addresses16,384
Network address
111.28.0.0
Broadcast address
111.28.63.255
First usable
111.28.0.1
Last usable
111.28.63.254
Usable hosts
16,382 (16,384 less the network and broadcast addresses)
Subnet mask
255.255.192.0
Wildcard mask
0.0.63.255 (Cisco ACLs, OSPF)
Prefix length
/18
Type
Public public
Old class
A (default /8)
As numbers
Hex 6F1C0000 · Integer 1864105984 to 1864122367
Reverse DNS zones
0.28.111.in-addr.arpa
1.28.111.in-addr.arpa
2.28.111.in-addr.arpa
3.28.111.in-addr.arpa
4.28.111.in-addr.arpa
5.28.111.in-addr.arpa
6.28.111.in-addr.arpa
7.28.111.in-addr.arpa
8.28.111.in-addr.arpa
9.28.111.in-addr.arpa
10.28.111.in-addr.arpa
11.28.111.in-addr.arpa
12.28.111.in-addr.arpa
13.28.111.in-addr.arpa
14.28.111.in-addr.arpa
15.28.111.in-addr.arpa
and 48 more
/18 is not on a 8-bit boundary, so it takes 64 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01101111.00011100.00000000.00000000111.28.0.0
Subnet mask11111111.11111111.11000000.00000000255.255.192.0
Network01101111.00011100.00000000.00000000111.28.0.0
Broadcast01101111.00011100.00111111.11111111111.28.63.255
Split into smaller subnets/30

111.28.0.0/18 makes 4,096 subnets of /30; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1111.28.0.0/30111.28.0.1 to 111.28.0.2111.28.0.32
2111.28.0.4/30111.28.0.5 to 111.28.0.6111.28.0.72
3111.28.0.8/30111.28.0.9 to 111.28.0.10111.28.0.112
4111.28.0.12/30111.28.0.13 to 111.28.0.14111.28.0.152
5111.28.0.16/30111.28.0.17 to 111.28.0.18111.28.0.192
6111.28.0.20/30111.28.0.21 to 111.28.0.22111.28.0.232
7111.28.0.24/30111.28.0.25 to 111.28.0.26111.28.0.272
8111.28.0.28/30111.28.0.29 to 111.28.0.30111.28.0.312
9111.28.0.32/30111.28.0.33 to 111.28.0.34111.28.0.352
10111.28.0.36/30111.28.0.37 to 111.28.0.38111.28.0.392
11111.28.0.40/30111.28.0.41 to 111.28.0.42111.28.0.432
12111.28.0.44/30111.28.0.45 to 111.28.0.46111.28.0.472
13111.28.0.48/30111.28.0.49 to 111.28.0.50111.28.0.512
14111.28.0.52/30111.28.0.53 to 111.28.0.54111.28.0.552
15111.28.0.56/30111.28.0.57 to 111.28.0.58111.28.0.592
16111.28.0.60/30111.28.0.61 to 111.28.0.62111.28.0.632
17111.28.0.64/30111.28.0.65 to 111.28.0.66111.28.0.672
18111.28.0.68/30111.28.0.69 to 111.28.0.70111.28.0.712
19111.28.0.72/30111.28.0.73 to 111.28.0.74111.28.0.752
20111.28.0.76/30111.28.0.77 to 111.28.0.78111.28.0.792
21111.28.0.80/30111.28.0.81 to 111.28.0.82111.28.0.832
22111.28.0.84/30111.28.0.85 to 111.28.0.86111.28.0.872
23111.28.0.88/30111.28.0.89 to 111.28.0.90111.28.0.912
24111.28.0.92/30111.28.0.93 to 111.28.0.94111.28.0.952
25111.28.0.96/30111.28.0.97 to 111.28.0.98111.28.0.992
26111.28.0.100/30111.28.0.101 to 111.28.0.102111.28.0.1032
27111.28.0.104/30111.28.0.105 to 111.28.0.106111.28.0.1072
28111.28.0.108/30111.28.0.109 to 111.28.0.110111.28.0.1112
29111.28.0.112/30111.28.0.113 to 111.28.0.114111.28.0.1152
30111.28.0.116/30111.28.0.117 to 111.28.0.118111.28.0.1192
31111.28.0.120/30111.28.0.121 to 111.28.0.122111.28.0.1232
32111.28.0.124/30111.28.0.125 to 111.28.0.126111.28.0.1272
33111.28.0.128/30111.28.0.129 to 111.28.0.130111.28.0.1312
34111.28.0.132/30111.28.0.133 to 111.28.0.134111.28.0.1352
35111.28.0.136/30111.28.0.137 to 111.28.0.138111.28.0.1392
36111.28.0.140/30111.28.0.141 to 111.28.0.142111.28.0.1432
37111.28.0.144/30111.28.0.145 to 111.28.0.146111.28.0.1472
38111.28.0.148/30111.28.0.149 to 111.28.0.150111.28.0.1512
39111.28.0.152/30111.28.0.153 to 111.28.0.154111.28.0.1552
40111.28.0.156/30111.28.0.157 to 111.28.0.158111.28.0.1592
41111.28.0.160/30111.28.0.161 to 111.28.0.162111.28.0.1632
42111.28.0.164/30111.28.0.165 to 111.28.0.166111.28.0.1672
43111.28.0.168/30111.28.0.169 to 111.28.0.170111.28.0.1712
44111.28.0.172/30111.28.0.173 to 111.28.0.174111.28.0.1752
45111.28.0.176/30111.28.0.177 to 111.28.0.178111.28.0.1792
46111.28.0.180/30111.28.0.181 to 111.28.0.182111.28.0.1832
47111.28.0.184/30111.28.0.185 to 111.28.0.186111.28.0.1872
48111.28.0.188/30111.28.0.189 to 111.28.0.190111.28.0.1912
49111.28.0.192/30111.28.0.193 to 111.28.0.194111.28.0.1952
50111.28.0.196/30111.28.0.197 to 111.28.0.198111.28.0.1992
51111.28.0.200/30111.28.0.201 to 111.28.0.202111.28.0.2032
52111.28.0.204/30111.28.0.205 to 111.28.0.206111.28.0.2072
53111.28.0.208/30111.28.0.209 to 111.28.0.210111.28.0.2112
54111.28.0.212/30111.28.0.213 to 111.28.0.214111.28.0.2152
55111.28.0.216/30111.28.0.217 to 111.28.0.218111.28.0.2192
56111.28.0.220/30111.28.0.221 to 111.28.0.222111.28.0.2232
57111.28.0.224/30111.28.0.225 to 111.28.0.226111.28.0.2272
58111.28.0.228/30111.28.0.229 to 111.28.0.230111.28.0.2312
59111.28.0.232/30111.28.0.233 to 111.28.0.234111.28.0.2352
60111.28.0.236/30111.28.0.237 to 111.28.0.238111.28.0.2392
61111.28.0.240/30111.28.0.241 to 111.28.0.242111.28.0.2432
62111.28.0.244/30111.28.0.245 to 111.28.0.246111.28.0.2472
63111.28.0.248/30111.28.0.249 to 111.28.0.250111.28.0.2512
64111.28.0.252/30111.28.0.253 to 111.28.0.254111.28.0.2552
65111.28.1.0/30111.28.1.1 to 111.28.1.2111.28.1.32
66111.28.1.4/30111.28.1.5 to 111.28.1.6111.28.1.72
67111.28.1.8/30111.28.1.9 to 111.28.1.10111.28.1.112
68111.28.1.12/30111.28.1.13 to 111.28.1.14111.28.1.152
69111.28.1.16/30111.28.1.17 to 111.28.1.18111.28.1.192
70111.28.1.20/30111.28.1.21 to 111.28.1.22111.28.1.232
71111.28.1.24/30111.28.1.25 to 111.28.1.26111.28.1.272
72111.28.1.28/30111.28.1.29 to 111.28.1.30111.28.1.312
73111.28.1.32/30111.28.1.33 to 111.28.1.34111.28.1.352
74111.28.1.36/30111.28.1.37 to 111.28.1.38111.28.1.392
75111.28.1.40/30111.28.1.41 to 111.28.1.42111.28.1.432
76111.28.1.44/30111.28.1.45 to 111.28.1.46111.28.1.472
77111.28.1.48/30111.28.1.49 to 111.28.1.50111.28.1.512
78111.28.1.52/30111.28.1.53 to 111.28.1.54111.28.1.552
79111.28.1.56/30111.28.1.57 to 111.28.1.58111.28.1.592
80111.28.1.60/30111.28.1.61 to 111.28.1.62111.28.1.632
81111.28.1.64/30111.28.1.65 to 111.28.1.66111.28.1.672
82111.28.1.68/30111.28.1.69 to 111.28.1.70111.28.1.712
83111.28.1.72/30111.28.1.73 to 111.28.1.74111.28.1.752
84111.28.1.76/30111.28.1.77 to 111.28.1.78111.28.1.792
85111.28.1.80/30111.28.1.81 to 111.28.1.82111.28.1.832
86111.28.1.84/30111.28.1.85 to 111.28.1.86111.28.1.872
87111.28.1.88/30111.28.1.89 to 111.28.1.90111.28.1.912
88111.28.1.92/30111.28.1.93 to 111.28.1.94111.28.1.952
89111.28.1.96/30111.28.1.97 to 111.28.1.98111.28.1.992
90111.28.1.100/30111.28.1.101 to 111.28.1.102111.28.1.1032
91111.28.1.104/30111.28.1.105 to 111.28.1.106111.28.1.1072
92111.28.1.108/30111.28.1.109 to 111.28.1.110111.28.1.1112
93111.28.1.112/30111.28.1.113 to 111.28.1.114111.28.1.1152
94111.28.1.116/30111.28.1.117 to 111.28.1.118111.28.1.1192
95111.28.1.120/30111.28.1.121 to 111.28.1.122111.28.1.1232
96111.28.1.124/30111.28.1.125 to 111.28.1.126111.28.1.1272
97111.28.1.128/30111.28.1.129 to 111.28.1.130111.28.1.1312
98111.28.1.132/30111.28.1.133 to 111.28.1.134111.28.1.1352
99111.28.1.136/30111.28.1.137 to 111.28.1.138111.28.1.1392
100111.28.1.140/30111.28.1.141 to 111.28.1.142111.28.1.1432
101111.28.1.144/30111.28.1.145 to 111.28.1.146111.28.1.1472
102111.28.1.148/30111.28.1.149 to 111.28.1.150111.28.1.1512
103111.28.1.152/30111.28.1.153 to 111.28.1.154111.28.1.1552
104111.28.1.156/30111.28.1.157 to 111.28.1.158111.28.1.1592
105111.28.1.160/30111.28.1.161 to 111.28.1.162111.28.1.1632
106111.28.1.164/30111.28.1.165 to 111.28.1.166111.28.1.1672
107111.28.1.168/30111.28.1.169 to 111.28.1.170111.28.1.1712
108111.28.1.172/30111.28.1.173 to 111.28.1.174111.28.1.1752
109111.28.1.176/30111.28.1.177 to 111.28.1.178111.28.1.1792
110111.28.1.180/30111.28.1.181 to 111.28.1.182111.28.1.1832
111111.28.1.184/30111.28.1.185 to 111.28.1.186111.28.1.1872
112111.28.1.188/30111.28.1.189 to 111.28.1.190111.28.1.1912
113111.28.1.192/30111.28.1.193 to 111.28.1.194111.28.1.1952
114111.28.1.196/30111.28.1.197 to 111.28.1.198111.28.1.1992
115111.28.1.200/30111.28.1.201 to 111.28.1.202111.28.1.2032
116111.28.1.204/30111.28.1.205 to 111.28.1.206111.28.1.2072
117111.28.1.208/30111.28.1.209 to 111.28.1.210111.28.1.2112
118111.28.1.212/30111.28.1.213 to 111.28.1.214111.28.1.2152
119111.28.1.216/30111.28.1.217 to 111.28.1.218111.28.1.2192
120111.28.1.220/30111.28.1.221 to 111.28.1.222111.28.1.2232
121111.28.1.224/30111.28.1.225 to 111.28.1.226111.28.1.2272
122111.28.1.228/30111.28.1.229 to 111.28.1.230111.28.1.2312
123111.28.1.232/30111.28.1.233 to 111.28.1.234111.28.1.2352
124111.28.1.236/30111.28.1.237 to 111.28.1.238111.28.1.2392
125111.28.1.240/30111.28.1.241 to 111.28.1.242111.28.1.2432
126111.28.1.244/30111.28.1.245 to 111.28.1.246111.28.1.2472
127111.28.1.248/30111.28.1.249 to 111.28.1.250111.28.1.2512
128111.28.1.252/30111.28.1.253 to 111.28.1.254111.28.1.2552
129111.28.2.0/30111.28.2.1 to 111.28.2.2111.28.2.32
130111.28.2.4/30111.28.2.5 to 111.28.2.6111.28.2.72
131111.28.2.8/30111.28.2.9 to 111.28.2.10111.28.2.112
132111.28.2.12/30111.28.2.13 to 111.28.2.14111.28.2.152
133111.28.2.16/30111.28.2.17 to 111.28.2.18111.28.2.192
134111.28.2.20/30111.28.2.21 to 111.28.2.22111.28.2.232
135111.28.2.24/30111.28.2.25 to 111.28.2.26111.28.2.272
136111.28.2.28/30111.28.2.29 to 111.28.2.30111.28.2.312
137111.28.2.32/30111.28.2.33 to 111.28.2.34111.28.2.352
138111.28.2.36/30111.28.2.37 to 111.28.2.38111.28.2.392
139111.28.2.40/30111.28.2.41 to 111.28.2.42111.28.2.432
140111.28.2.44/30111.28.2.45 to 111.28.2.46111.28.2.472
141111.28.2.48/30111.28.2.49 to 111.28.2.50111.28.2.512
142111.28.2.52/30111.28.2.53 to 111.28.2.54111.28.2.552
143111.28.2.56/30111.28.2.57 to 111.28.2.58111.28.2.592
144111.28.2.60/30111.28.2.61 to 111.28.2.62111.28.2.632
145111.28.2.64/30111.28.2.65 to 111.28.2.66111.28.2.672
146111.28.2.68/30111.28.2.69 to 111.28.2.70111.28.2.712
147111.28.2.72/30111.28.2.73 to 111.28.2.74111.28.2.752
148111.28.2.76/30111.28.2.77 to 111.28.2.78111.28.2.792
149111.28.2.80/30111.28.2.81 to 111.28.2.82111.28.2.832
150111.28.2.84/30111.28.2.85 to 111.28.2.86111.28.2.872
151111.28.2.88/30111.28.2.89 to 111.28.2.90111.28.2.912
152111.28.2.92/30111.28.2.93 to 111.28.2.94111.28.2.952
153111.28.2.96/30111.28.2.97 to 111.28.2.98111.28.2.992
154111.28.2.100/30111.28.2.101 to 111.28.2.102111.28.2.1032
155111.28.2.104/30111.28.2.105 to 111.28.2.106111.28.2.1072
156111.28.2.108/30111.28.2.109 to 111.28.2.110111.28.2.1112
157111.28.2.112/30111.28.2.113 to 111.28.2.114111.28.2.1152
158111.28.2.116/30111.28.2.117 to 111.28.2.118111.28.2.1192
159111.28.2.120/30111.28.2.121 to 111.28.2.122111.28.2.1232
160111.28.2.124/30111.28.2.125 to 111.28.2.126111.28.2.1272
161111.28.2.128/30111.28.2.129 to 111.28.2.130111.28.2.1312
162111.28.2.132/30111.28.2.133 to 111.28.2.134111.28.2.1352
163111.28.2.136/30111.28.2.137 to 111.28.2.138111.28.2.1392
164111.28.2.140/30111.28.2.141 to 111.28.2.142111.28.2.1432
165111.28.2.144/30111.28.2.145 to 111.28.2.146111.28.2.1472
166111.28.2.148/30111.28.2.149 to 111.28.2.150111.28.2.1512
167111.28.2.152/30111.28.2.153 to 111.28.2.154111.28.2.1552
168111.28.2.156/30111.28.2.157 to 111.28.2.158111.28.2.1592
169111.28.2.160/30111.28.2.161 to 111.28.2.162111.28.2.1632
170111.28.2.164/30111.28.2.165 to 111.28.2.166111.28.2.1672
171111.28.2.168/30111.28.2.169 to 111.28.2.170111.28.2.1712
172111.28.2.172/30111.28.2.173 to 111.28.2.174111.28.2.1752
173111.28.2.176/30111.28.2.177 to 111.28.2.178111.28.2.1792
174111.28.2.180/30111.28.2.181 to 111.28.2.182111.28.2.1832
175111.28.2.184/30111.28.2.185 to 111.28.2.186111.28.2.1872
176111.28.2.188/30111.28.2.189 to 111.28.2.190111.28.2.1912
177111.28.2.192/30111.28.2.193 to 111.28.2.194111.28.2.1952
178111.28.2.196/30111.28.2.197 to 111.28.2.198111.28.2.1992
179111.28.2.200/30111.28.2.201 to 111.28.2.202111.28.2.2032
180111.28.2.204/30111.28.2.205 to 111.28.2.206111.28.2.2072
181111.28.2.208/30111.28.2.209 to 111.28.2.210111.28.2.2112
182111.28.2.212/30111.28.2.213 to 111.28.2.214111.28.2.2152
183111.28.2.216/30111.28.2.217 to 111.28.2.218111.28.2.2192
184111.28.2.220/30111.28.2.221 to 111.28.2.222111.28.2.2232
185111.28.2.224/30111.28.2.225 to 111.28.2.226111.28.2.2272
186111.28.2.228/30111.28.2.229 to 111.28.2.230111.28.2.2312
187111.28.2.232/30111.28.2.233 to 111.28.2.234111.28.2.2352
188111.28.2.236/30111.28.2.237 to 111.28.2.238111.28.2.2392
189111.28.2.240/30111.28.2.241 to 111.28.2.242111.28.2.2432
190111.28.2.244/30111.28.2.245 to 111.28.2.246111.28.2.2472
191111.28.2.248/30111.28.2.249 to 111.28.2.250111.28.2.2512
192111.28.2.252/30111.28.2.253 to 111.28.2.254111.28.2.2552
193111.28.3.0/30111.28.3.1 to 111.28.3.2111.28.3.32
194111.28.3.4/30111.28.3.5 to 111.28.3.6111.28.3.72
195111.28.3.8/30111.28.3.9 to 111.28.3.10111.28.3.112
196111.28.3.12/30111.28.3.13 to 111.28.3.14111.28.3.152
197111.28.3.16/30111.28.3.17 to 111.28.3.18111.28.3.192
198111.28.3.20/30111.28.3.21 to 111.28.3.22111.28.3.232
199111.28.3.24/30111.28.3.25 to 111.28.3.26111.28.3.272
200111.28.3.28/30111.28.3.29 to 111.28.3.30111.28.3.312
201111.28.3.32/30111.28.3.33 to 111.28.3.34111.28.3.352
202111.28.3.36/30111.28.3.37 to 111.28.3.38111.28.3.392
203111.28.3.40/30111.28.3.41 to 111.28.3.42111.28.3.432
204111.28.3.44/30111.28.3.45 to 111.28.3.46111.28.3.472
205111.28.3.48/30111.28.3.49 to 111.28.3.50111.28.3.512
206111.28.3.52/30111.28.3.53 to 111.28.3.54111.28.3.552
207111.28.3.56/30111.28.3.57 to 111.28.3.58111.28.3.592
208111.28.3.60/30111.28.3.61 to 111.28.3.62111.28.3.632
209111.28.3.64/30111.28.3.65 to 111.28.3.66111.28.3.672
210111.28.3.68/30111.28.3.69 to 111.28.3.70111.28.3.712
211111.28.3.72/30111.28.3.73 to 111.28.3.74111.28.3.752
212111.28.3.76/30111.28.3.77 to 111.28.3.78111.28.3.792
213111.28.3.80/30111.28.3.81 to 111.28.3.82111.28.3.832
214111.28.3.84/30111.28.3.85 to 111.28.3.86111.28.3.872
215111.28.3.88/30111.28.3.89 to 111.28.3.90111.28.3.912
216111.28.3.92/30111.28.3.93 to 111.28.3.94111.28.3.952
217111.28.3.96/30111.28.3.97 to 111.28.3.98111.28.3.992
218111.28.3.100/30111.28.3.101 to 111.28.3.102111.28.3.1032
219111.28.3.104/30111.28.3.105 to 111.28.3.106111.28.3.1072
220111.28.3.108/30111.28.3.109 to 111.28.3.110111.28.3.1112
221111.28.3.112/30111.28.3.113 to 111.28.3.114111.28.3.1152
222111.28.3.116/30111.28.3.117 to 111.28.3.118111.28.3.1192
223111.28.3.120/30111.28.3.121 to 111.28.3.122111.28.3.1232
224111.28.3.124/30111.28.3.125 to 111.28.3.126111.28.3.1272
225111.28.3.128/30111.28.3.129 to 111.28.3.130111.28.3.1312
226111.28.3.132/30111.28.3.133 to 111.28.3.134111.28.3.1352
227111.28.3.136/30111.28.3.137 to 111.28.3.138111.28.3.1392
228111.28.3.140/30111.28.3.141 to 111.28.3.142111.28.3.1432
229111.28.3.144/30111.28.3.145 to 111.28.3.146111.28.3.1472
230111.28.3.148/30111.28.3.149 to 111.28.3.150111.28.3.1512
231111.28.3.152/30111.28.3.153 to 111.28.3.154111.28.3.1552
232111.28.3.156/30111.28.3.157 to 111.28.3.158111.28.3.1592
233111.28.3.160/30111.28.3.161 to 111.28.3.162111.28.3.1632
234111.28.3.164/30111.28.3.165 to 111.28.3.166111.28.3.1672
235111.28.3.168/30111.28.3.169 to 111.28.3.170111.28.3.1712
236111.28.3.172/30111.28.3.173 to 111.28.3.174111.28.3.1752
237111.28.3.176/30111.28.3.177 to 111.28.3.178111.28.3.1792
238111.28.3.180/30111.28.3.181 to 111.28.3.182111.28.3.1832
239111.28.3.184/30111.28.3.185 to 111.28.3.186111.28.3.1872
240111.28.3.188/30111.28.3.189 to 111.28.3.190111.28.3.1912
241111.28.3.192/30111.28.3.193 to 111.28.3.194111.28.3.1952
242111.28.3.196/30111.28.3.197 to 111.28.3.198111.28.3.1992
243111.28.3.200/30111.28.3.201 to 111.28.3.202111.28.3.2032
244111.28.3.204/30111.28.3.205 to 111.28.3.206111.28.3.2072
245111.28.3.208/30111.28.3.209 to 111.28.3.210111.28.3.2112
246111.28.3.212/30111.28.3.213 to 111.28.3.214111.28.3.2152
247111.28.3.216/30111.28.3.217 to 111.28.3.218111.28.3.2192
248111.28.3.220/30111.28.3.221 to 111.28.3.222111.28.3.2232
249111.28.3.224/30111.28.3.225 to 111.28.3.226111.28.3.2272
250111.28.3.228/30111.28.3.229 to 111.28.3.230111.28.3.2312
251111.28.3.232/30111.28.3.233 to 111.28.3.234111.28.3.2352
252111.28.3.236/30111.28.3.237 to 111.28.3.238111.28.3.2392
253111.28.3.240/30111.28.3.241 to 111.28.3.242111.28.3.2432
254111.28.3.244/30111.28.3.245 to 111.28.3.246111.28.3.2472
255111.28.3.248/30111.28.3.249 to 111.28.3.250111.28.3.2512
256111.28.3.252/30111.28.3.253 to 111.28.3.254111.28.3.2552

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