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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.

Network158.17.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
158.17.0.0
Broadcast address
158.17.127.255
First usable
158.17.0.1
Last usable
158.17.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Public public
Old class
B (default /16)
As numbers
Hex 9E110000 · Integer 2651914240 to 2651947007
Reverse DNS zones
0.17.158.in-addr.arpa
1.17.158.in-addr.arpa
2.17.158.in-addr.arpa
3.17.158.in-addr.arpa
4.17.158.in-addr.arpa
5.17.158.in-addr.arpa
6.17.158.in-addr.arpa
7.17.158.in-addr.arpa
8.17.158.in-addr.arpa
9.17.158.in-addr.arpa
10.17.158.in-addr.arpa
11.17.158.in-addr.arpa
12.17.158.in-addr.arpa
13.17.158.in-addr.arpa
14.17.158.in-addr.arpa
15.17.158.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011110.00010001.00000000.00000000158.17.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network10011110.00010001.00000000.00000000158.17.0.0
Broadcast10011110.00010001.01111111.11111111158.17.127.255
Split into smaller subnets/29

158.17.0.0/17 makes 4,096 subnets of /29; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1158.17.0.0/29158.17.0.1 to 158.17.0.6158.17.0.76
2158.17.0.8/29158.17.0.9 to 158.17.0.14158.17.0.156
3158.17.0.16/29158.17.0.17 to 158.17.0.22158.17.0.236
4158.17.0.24/29158.17.0.25 to 158.17.0.30158.17.0.316
5158.17.0.32/29158.17.0.33 to 158.17.0.38158.17.0.396
6158.17.0.40/29158.17.0.41 to 158.17.0.46158.17.0.476
7158.17.0.48/29158.17.0.49 to 158.17.0.54158.17.0.556
8158.17.0.56/29158.17.0.57 to 158.17.0.62158.17.0.636
9158.17.0.64/29158.17.0.65 to 158.17.0.70158.17.0.716
10158.17.0.72/29158.17.0.73 to 158.17.0.78158.17.0.796
11158.17.0.80/29158.17.0.81 to 158.17.0.86158.17.0.876
12158.17.0.88/29158.17.0.89 to 158.17.0.94158.17.0.956
13158.17.0.96/29158.17.0.97 to 158.17.0.102158.17.0.1036
14158.17.0.104/29158.17.0.105 to 158.17.0.110158.17.0.1116
15158.17.0.112/29158.17.0.113 to 158.17.0.118158.17.0.1196
16158.17.0.120/29158.17.0.121 to 158.17.0.126158.17.0.1276
17158.17.0.128/29158.17.0.129 to 158.17.0.134158.17.0.1356
18158.17.0.136/29158.17.0.137 to 158.17.0.142158.17.0.1436
19158.17.0.144/29158.17.0.145 to 158.17.0.150158.17.0.1516
20158.17.0.152/29158.17.0.153 to 158.17.0.158158.17.0.1596
21158.17.0.160/29158.17.0.161 to 158.17.0.166158.17.0.1676
22158.17.0.168/29158.17.0.169 to 158.17.0.174158.17.0.1756
23158.17.0.176/29158.17.0.177 to 158.17.0.182158.17.0.1836
24158.17.0.184/29158.17.0.185 to 158.17.0.190158.17.0.1916
25158.17.0.192/29158.17.0.193 to 158.17.0.198158.17.0.1996
26158.17.0.200/29158.17.0.201 to 158.17.0.206158.17.0.2076
27158.17.0.208/29158.17.0.209 to 158.17.0.214158.17.0.2156
28158.17.0.216/29158.17.0.217 to 158.17.0.222158.17.0.2236
29158.17.0.224/29158.17.0.225 to 158.17.0.230158.17.0.2316
30158.17.0.232/29158.17.0.233 to 158.17.0.238158.17.0.2396
31158.17.0.240/29158.17.0.241 to 158.17.0.246158.17.0.2476
32158.17.0.248/29158.17.0.249 to 158.17.0.254158.17.0.2556
33158.17.1.0/29158.17.1.1 to 158.17.1.6158.17.1.76
34158.17.1.8/29158.17.1.9 to 158.17.1.14158.17.1.156
35158.17.1.16/29158.17.1.17 to 158.17.1.22158.17.1.236
36158.17.1.24/29158.17.1.25 to 158.17.1.30158.17.1.316
37158.17.1.32/29158.17.1.33 to 158.17.1.38158.17.1.396
38158.17.1.40/29158.17.1.41 to 158.17.1.46158.17.1.476
39158.17.1.48/29158.17.1.49 to 158.17.1.54158.17.1.556
40158.17.1.56/29158.17.1.57 to 158.17.1.62158.17.1.636
41158.17.1.64/29158.17.1.65 to 158.17.1.70158.17.1.716
42158.17.1.72/29158.17.1.73 to 158.17.1.78158.17.1.796
43158.17.1.80/29158.17.1.81 to 158.17.1.86158.17.1.876
44158.17.1.88/29158.17.1.89 to 158.17.1.94158.17.1.956
45158.17.1.96/29158.17.1.97 to 158.17.1.102158.17.1.1036
46158.17.1.104/29158.17.1.105 to 158.17.1.110158.17.1.1116
47158.17.1.112/29158.17.1.113 to 158.17.1.118158.17.1.1196
48158.17.1.120/29158.17.1.121 to 158.17.1.126158.17.1.1276
49158.17.1.128/29158.17.1.129 to 158.17.1.134158.17.1.1356
50158.17.1.136/29158.17.1.137 to 158.17.1.142158.17.1.1436
51158.17.1.144/29158.17.1.145 to 158.17.1.150158.17.1.1516
52158.17.1.152/29158.17.1.153 to 158.17.1.158158.17.1.1596
53158.17.1.160/29158.17.1.161 to 158.17.1.166158.17.1.1676
54158.17.1.168/29158.17.1.169 to 158.17.1.174158.17.1.1756
55158.17.1.176/29158.17.1.177 to 158.17.1.182158.17.1.1836
56158.17.1.184/29158.17.1.185 to 158.17.1.190158.17.1.1916
57158.17.1.192/29158.17.1.193 to 158.17.1.198158.17.1.1996
58158.17.1.200/29158.17.1.201 to 158.17.1.206158.17.1.2076
59158.17.1.208/29158.17.1.209 to 158.17.1.214158.17.1.2156
60158.17.1.216/29158.17.1.217 to 158.17.1.222158.17.1.2236
61158.17.1.224/29158.17.1.225 to 158.17.1.230158.17.1.2316
62158.17.1.232/29158.17.1.233 to 158.17.1.238158.17.1.2396
63158.17.1.240/29158.17.1.241 to 158.17.1.246158.17.1.2476
64158.17.1.248/29158.17.1.249 to 158.17.1.254158.17.1.2556
65158.17.2.0/29158.17.2.1 to 158.17.2.6158.17.2.76
66158.17.2.8/29158.17.2.9 to 158.17.2.14158.17.2.156
67158.17.2.16/29158.17.2.17 to 158.17.2.22158.17.2.236
68158.17.2.24/29158.17.2.25 to 158.17.2.30158.17.2.316
69158.17.2.32/29158.17.2.33 to 158.17.2.38158.17.2.396
70158.17.2.40/29158.17.2.41 to 158.17.2.46158.17.2.476
71158.17.2.48/29158.17.2.49 to 158.17.2.54158.17.2.556
72158.17.2.56/29158.17.2.57 to 158.17.2.62158.17.2.636
73158.17.2.64/29158.17.2.65 to 158.17.2.70158.17.2.716
74158.17.2.72/29158.17.2.73 to 158.17.2.78158.17.2.796
75158.17.2.80/29158.17.2.81 to 158.17.2.86158.17.2.876
76158.17.2.88/29158.17.2.89 to 158.17.2.94158.17.2.956
77158.17.2.96/29158.17.2.97 to 158.17.2.102158.17.2.1036
78158.17.2.104/29158.17.2.105 to 158.17.2.110158.17.2.1116
79158.17.2.112/29158.17.2.113 to 158.17.2.118158.17.2.1196
80158.17.2.120/29158.17.2.121 to 158.17.2.126158.17.2.1276
81158.17.2.128/29158.17.2.129 to 158.17.2.134158.17.2.1356
82158.17.2.136/29158.17.2.137 to 158.17.2.142158.17.2.1436
83158.17.2.144/29158.17.2.145 to 158.17.2.150158.17.2.1516
84158.17.2.152/29158.17.2.153 to 158.17.2.158158.17.2.1596
85158.17.2.160/29158.17.2.161 to 158.17.2.166158.17.2.1676
86158.17.2.168/29158.17.2.169 to 158.17.2.174158.17.2.1756
87158.17.2.176/29158.17.2.177 to 158.17.2.182158.17.2.1836
88158.17.2.184/29158.17.2.185 to 158.17.2.190158.17.2.1916
89158.17.2.192/29158.17.2.193 to 158.17.2.198158.17.2.1996
90158.17.2.200/29158.17.2.201 to 158.17.2.206158.17.2.2076
91158.17.2.208/29158.17.2.209 to 158.17.2.214158.17.2.2156
92158.17.2.216/29158.17.2.217 to 158.17.2.222158.17.2.2236
93158.17.2.224/29158.17.2.225 to 158.17.2.230158.17.2.2316
94158.17.2.232/29158.17.2.233 to 158.17.2.238158.17.2.2396
95158.17.2.240/29158.17.2.241 to 158.17.2.246158.17.2.2476
96158.17.2.248/29158.17.2.249 to 158.17.2.254158.17.2.2556
97158.17.3.0/29158.17.3.1 to 158.17.3.6158.17.3.76
98158.17.3.8/29158.17.3.9 to 158.17.3.14158.17.3.156
99158.17.3.16/29158.17.3.17 to 158.17.3.22158.17.3.236
100158.17.3.24/29158.17.3.25 to 158.17.3.30158.17.3.316
101158.17.3.32/29158.17.3.33 to 158.17.3.38158.17.3.396
102158.17.3.40/29158.17.3.41 to 158.17.3.46158.17.3.476
103158.17.3.48/29158.17.3.49 to 158.17.3.54158.17.3.556
104158.17.3.56/29158.17.3.57 to 158.17.3.62158.17.3.636
105158.17.3.64/29158.17.3.65 to 158.17.3.70158.17.3.716
106158.17.3.72/29158.17.3.73 to 158.17.3.78158.17.3.796
107158.17.3.80/29158.17.3.81 to 158.17.3.86158.17.3.876
108158.17.3.88/29158.17.3.89 to 158.17.3.94158.17.3.956
109158.17.3.96/29158.17.3.97 to 158.17.3.102158.17.3.1036
110158.17.3.104/29158.17.3.105 to 158.17.3.110158.17.3.1116
111158.17.3.112/29158.17.3.113 to 158.17.3.118158.17.3.1196
112158.17.3.120/29158.17.3.121 to 158.17.3.126158.17.3.1276
113158.17.3.128/29158.17.3.129 to 158.17.3.134158.17.3.1356
114158.17.3.136/29158.17.3.137 to 158.17.3.142158.17.3.1436
115158.17.3.144/29158.17.3.145 to 158.17.3.150158.17.3.1516
116158.17.3.152/29158.17.3.153 to 158.17.3.158158.17.3.1596
117158.17.3.160/29158.17.3.161 to 158.17.3.166158.17.3.1676
118158.17.3.168/29158.17.3.169 to 158.17.3.174158.17.3.1756
119158.17.3.176/29158.17.3.177 to 158.17.3.182158.17.3.1836
120158.17.3.184/29158.17.3.185 to 158.17.3.190158.17.3.1916
121158.17.3.192/29158.17.3.193 to 158.17.3.198158.17.3.1996
122158.17.3.200/29158.17.3.201 to 158.17.3.206158.17.3.2076
123158.17.3.208/29158.17.3.209 to 158.17.3.214158.17.3.2156
124158.17.3.216/29158.17.3.217 to 158.17.3.222158.17.3.2236
125158.17.3.224/29158.17.3.225 to 158.17.3.230158.17.3.2316
126158.17.3.232/29158.17.3.233 to 158.17.3.238158.17.3.2396
127158.17.3.240/29158.17.3.241 to 158.17.3.246158.17.3.2476
128158.17.3.248/29158.17.3.249 to 158.17.3.254158.17.3.2556
129158.17.4.0/29158.17.4.1 to 158.17.4.6158.17.4.76
130158.17.4.8/29158.17.4.9 to 158.17.4.14158.17.4.156
131158.17.4.16/29158.17.4.17 to 158.17.4.22158.17.4.236
132158.17.4.24/29158.17.4.25 to 158.17.4.30158.17.4.316
133158.17.4.32/29158.17.4.33 to 158.17.4.38158.17.4.396
134158.17.4.40/29158.17.4.41 to 158.17.4.46158.17.4.476
135158.17.4.48/29158.17.4.49 to 158.17.4.54158.17.4.556
136158.17.4.56/29158.17.4.57 to 158.17.4.62158.17.4.636
137158.17.4.64/29158.17.4.65 to 158.17.4.70158.17.4.716
138158.17.4.72/29158.17.4.73 to 158.17.4.78158.17.4.796
139158.17.4.80/29158.17.4.81 to 158.17.4.86158.17.4.876
140158.17.4.88/29158.17.4.89 to 158.17.4.94158.17.4.956
141158.17.4.96/29158.17.4.97 to 158.17.4.102158.17.4.1036
142158.17.4.104/29158.17.4.105 to 158.17.4.110158.17.4.1116
143158.17.4.112/29158.17.4.113 to 158.17.4.118158.17.4.1196
144158.17.4.120/29158.17.4.121 to 158.17.4.126158.17.4.1276
145158.17.4.128/29158.17.4.129 to 158.17.4.134158.17.4.1356
146158.17.4.136/29158.17.4.137 to 158.17.4.142158.17.4.1436
147158.17.4.144/29158.17.4.145 to 158.17.4.150158.17.4.1516
148158.17.4.152/29158.17.4.153 to 158.17.4.158158.17.4.1596
149158.17.4.160/29158.17.4.161 to 158.17.4.166158.17.4.1676
150158.17.4.168/29158.17.4.169 to 158.17.4.174158.17.4.1756
151158.17.4.176/29158.17.4.177 to 158.17.4.182158.17.4.1836
152158.17.4.184/29158.17.4.185 to 158.17.4.190158.17.4.1916
153158.17.4.192/29158.17.4.193 to 158.17.4.198158.17.4.1996
154158.17.4.200/29158.17.4.201 to 158.17.4.206158.17.4.2076
155158.17.4.208/29158.17.4.209 to 158.17.4.214158.17.4.2156
156158.17.4.216/29158.17.4.217 to 158.17.4.222158.17.4.2236
157158.17.4.224/29158.17.4.225 to 158.17.4.230158.17.4.2316
158158.17.4.232/29158.17.4.233 to 158.17.4.238158.17.4.2396
159158.17.4.240/29158.17.4.241 to 158.17.4.246158.17.4.2476
160158.17.4.248/29158.17.4.249 to 158.17.4.254158.17.4.2556
161158.17.5.0/29158.17.5.1 to 158.17.5.6158.17.5.76
162158.17.5.8/29158.17.5.9 to 158.17.5.14158.17.5.156
163158.17.5.16/29158.17.5.17 to 158.17.5.22158.17.5.236
164158.17.5.24/29158.17.5.25 to 158.17.5.30158.17.5.316
165158.17.5.32/29158.17.5.33 to 158.17.5.38158.17.5.396
166158.17.5.40/29158.17.5.41 to 158.17.5.46158.17.5.476
167158.17.5.48/29158.17.5.49 to 158.17.5.54158.17.5.556
168158.17.5.56/29158.17.5.57 to 158.17.5.62158.17.5.636
169158.17.5.64/29158.17.5.65 to 158.17.5.70158.17.5.716
170158.17.5.72/29158.17.5.73 to 158.17.5.78158.17.5.796
171158.17.5.80/29158.17.5.81 to 158.17.5.86158.17.5.876
172158.17.5.88/29158.17.5.89 to 158.17.5.94158.17.5.956
173158.17.5.96/29158.17.5.97 to 158.17.5.102158.17.5.1036
174158.17.5.104/29158.17.5.105 to 158.17.5.110158.17.5.1116
175158.17.5.112/29158.17.5.113 to 158.17.5.118158.17.5.1196
176158.17.5.120/29158.17.5.121 to 158.17.5.126158.17.5.1276
177158.17.5.128/29158.17.5.129 to 158.17.5.134158.17.5.1356
178158.17.5.136/29158.17.5.137 to 158.17.5.142158.17.5.1436
179158.17.5.144/29158.17.5.145 to 158.17.5.150158.17.5.1516
180158.17.5.152/29158.17.5.153 to 158.17.5.158158.17.5.1596
181158.17.5.160/29158.17.5.161 to 158.17.5.166158.17.5.1676
182158.17.5.168/29158.17.5.169 to 158.17.5.174158.17.5.1756
183158.17.5.176/29158.17.5.177 to 158.17.5.182158.17.5.1836
184158.17.5.184/29158.17.5.185 to 158.17.5.190158.17.5.1916
185158.17.5.192/29158.17.5.193 to 158.17.5.198158.17.5.1996
186158.17.5.200/29158.17.5.201 to 158.17.5.206158.17.5.2076
187158.17.5.208/29158.17.5.209 to 158.17.5.214158.17.5.2156
188158.17.5.216/29158.17.5.217 to 158.17.5.222158.17.5.2236
189158.17.5.224/29158.17.5.225 to 158.17.5.230158.17.5.2316
190158.17.5.232/29158.17.5.233 to 158.17.5.238158.17.5.2396
191158.17.5.240/29158.17.5.241 to 158.17.5.246158.17.5.2476
192158.17.5.248/29158.17.5.249 to 158.17.5.254158.17.5.2556
193158.17.6.0/29158.17.6.1 to 158.17.6.6158.17.6.76
194158.17.6.8/29158.17.6.9 to 158.17.6.14158.17.6.156
195158.17.6.16/29158.17.6.17 to 158.17.6.22158.17.6.236
196158.17.6.24/29158.17.6.25 to 158.17.6.30158.17.6.316
197158.17.6.32/29158.17.6.33 to 158.17.6.38158.17.6.396
198158.17.6.40/29158.17.6.41 to 158.17.6.46158.17.6.476
199158.17.6.48/29158.17.6.49 to 158.17.6.54158.17.6.556
200158.17.6.56/29158.17.6.57 to 158.17.6.62158.17.6.636
201158.17.6.64/29158.17.6.65 to 158.17.6.70158.17.6.716
202158.17.6.72/29158.17.6.73 to 158.17.6.78158.17.6.796
203158.17.6.80/29158.17.6.81 to 158.17.6.86158.17.6.876
204158.17.6.88/29158.17.6.89 to 158.17.6.94158.17.6.956
205158.17.6.96/29158.17.6.97 to 158.17.6.102158.17.6.1036
206158.17.6.104/29158.17.6.105 to 158.17.6.110158.17.6.1116
207158.17.6.112/29158.17.6.113 to 158.17.6.118158.17.6.1196
208158.17.6.120/29158.17.6.121 to 158.17.6.126158.17.6.1276
209158.17.6.128/29158.17.6.129 to 158.17.6.134158.17.6.1356
210158.17.6.136/29158.17.6.137 to 158.17.6.142158.17.6.1436
211158.17.6.144/29158.17.6.145 to 158.17.6.150158.17.6.1516
212158.17.6.152/29158.17.6.153 to 158.17.6.158158.17.6.1596
213158.17.6.160/29158.17.6.161 to 158.17.6.166158.17.6.1676
214158.17.6.168/29158.17.6.169 to 158.17.6.174158.17.6.1756
215158.17.6.176/29158.17.6.177 to 158.17.6.182158.17.6.1836
216158.17.6.184/29158.17.6.185 to 158.17.6.190158.17.6.1916
217158.17.6.192/29158.17.6.193 to 158.17.6.198158.17.6.1996
218158.17.6.200/29158.17.6.201 to 158.17.6.206158.17.6.2076
219158.17.6.208/29158.17.6.209 to 158.17.6.214158.17.6.2156
220158.17.6.216/29158.17.6.217 to 158.17.6.222158.17.6.2236
221158.17.6.224/29158.17.6.225 to 158.17.6.230158.17.6.2316
222158.17.6.232/29158.17.6.233 to 158.17.6.238158.17.6.2396
223158.17.6.240/29158.17.6.241 to 158.17.6.246158.17.6.2476
224158.17.6.248/29158.17.6.249 to 158.17.6.254158.17.6.2556
225158.17.7.0/29158.17.7.1 to 158.17.7.6158.17.7.76
226158.17.7.8/29158.17.7.9 to 158.17.7.14158.17.7.156
227158.17.7.16/29158.17.7.17 to 158.17.7.22158.17.7.236
228158.17.7.24/29158.17.7.25 to 158.17.7.30158.17.7.316
229158.17.7.32/29158.17.7.33 to 158.17.7.38158.17.7.396
230158.17.7.40/29158.17.7.41 to 158.17.7.46158.17.7.476
231158.17.7.48/29158.17.7.49 to 158.17.7.54158.17.7.556
232158.17.7.56/29158.17.7.57 to 158.17.7.62158.17.7.636
233158.17.7.64/29158.17.7.65 to 158.17.7.70158.17.7.716
234158.17.7.72/29158.17.7.73 to 158.17.7.78158.17.7.796
235158.17.7.80/29158.17.7.81 to 158.17.7.86158.17.7.876
236158.17.7.88/29158.17.7.89 to 158.17.7.94158.17.7.956
237158.17.7.96/29158.17.7.97 to 158.17.7.102158.17.7.1036
238158.17.7.104/29158.17.7.105 to 158.17.7.110158.17.7.1116
239158.17.7.112/29158.17.7.113 to 158.17.7.118158.17.7.1196
240158.17.7.120/29158.17.7.121 to 158.17.7.126158.17.7.1276
241158.17.7.128/29158.17.7.129 to 158.17.7.134158.17.7.1356
242158.17.7.136/29158.17.7.137 to 158.17.7.142158.17.7.1436
243158.17.7.144/29158.17.7.145 to 158.17.7.150158.17.7.1516
244158.17.7.152/29158.17.7.153 to 158.17.7.158158.17.7.1596
245158.17.7.160/29158.17.7.161 to 158.17.7.166158.17.7.1676
246158.17.7.168/29158.17.7.169 to 158.17.7.174158.17.7.1756
247158.17.7.176/29158.17.7.177 to 158.17.7.182158.17.7.1836
248158.17.7.184/29158.17.7.185 to 158.17.7.190158.17.7.1916
249158.17.7.192/29158.17.7.193 to 158.17.7.198158.17.7.1996
250158.17.7.200/29158.17.7.201 to 158.17.7.206158.17.7.2076
251158.17.7.208/29158.17.7.209 to 158.17.7.214158.17.7.2156
252158.17.7.216/29158.17.7.217 to 158.17.7.222158.17.7.2236
253158.17.7.224/29158.17.7.225 to 158.17.7.230158.17.7.2316
254158.17.7.232/29158.17.7.233 to 158.17.7.238158.17.7.2396
255158.17.7.240/29158.17.7.241 to 158.17.7.246158.17.7.2476
256158.17.7.248/29158.17.7.249 to 158.17.7.254158.17.7.2556

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