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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.

Network238.3.32.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
238.3.32.0
Broadcast address
238.3.63.255
First usable
238.3.32.1
Last usable
238.3.63.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex EE032000 · Integer 3993182208 to 3993190399
Reverse DNS zones
32.3.238.in-addr.arpa
33.3.238.in-addr.arpa
34.3.238.in-addr.arpa
35.3.238.in-addr.arpa
36.3.238.in-addr.arpa
37.3.238.in-addr.arpa
38.3.238.in-addr.arpa
39.3.238.in-addr.arpa
40.3.238.in-addr.arpa
41.3.238.in-addr.arpa
42.3.238.in-addr.arpa
43.3.238.in-addr.arpa
44.3.238.in-addr.arpa
45.3.238.in-addr.arpa
46.3.238.in-addr.arpa
47.3.238.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11101110.00000011.00100000.00000000238.3.32.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network11101110.00000011.00100000.00000000238.3.32.0
Broadcast11101110.00000011.00111111.11111111238.3.63.255
Split into smaller subnets/29

238.3.32.0/19 makes 1,024 subnets of /29; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1238.3.32.0/29238.3.32.1 to 238.3.32.6238.3.32.76
2238.3.32.8/29238.3.32.9 to 238.3.32.14238.3.32.156
3238.3.32.16/29238.3.32.17 to 238.3.32.22238.3.32.236
4238.3.32.24/29238.3.32.25 to 238.3.32.30238.3.32.316
5238.3.32.32/29238.3.32.33 to 238.3.32.38238.3.32.396
6238.3.32.40/29238.3.32.41 to 238.3.32.46238.3.32.476
7238.3.32.48/29238.3.32.49 to 238.3.32.54238.3.32.556
8238.3.32.56/29238.3.32.57 to 238.3.32.62238.3.32.636
9238.3.32.64/29238.3.32.65 to 238.3.32.70238.3.32.716
10238.3.32.72/29238.3.32.73 to 238.3.32.78238.3.32.796
11238.3.32.80/29238.3.32.81 to 238.3.32.86238.3.32.876
12238.3.32.88/29238.3.32.89 to 238.3.32.94238.3.32.956
13238.3.32.96/29238.3.32.97 to 238.3.32.102238.3.32.1036
14238.3.32.104/29238.3.32.105 to 238.3.32.110238.3.32.1116
15238.3.32.112/29238.3.32.113 to 238.3.32.118238.3.32.1196
16238.3.32.120/29238.3.32.121 to 238.3.32.126238.3.32.1276
17238.3.32.128/29238.3.32.129 to 238.3.32.134238.3.32.1356
18238.3.32.136/29238.3.32.137 to 238.3.32.142238.3.32.1436
19238.3.32.144/29238.3.32.145 to 238.3.32.150238.3.32.1516
20238.3.32.152/29238.3.32.153 to 238.3.32.158238.3.32.1596
21238.3.32.160/29238.3.32.161 to 238.3.32.166238.3.32.1676
22238.3.32.168/29238.3.32.169 to 238.3.32.174238.3.32.1756
23238.3.32.176/29238.3.32.177 to 238.3.32.182238.3.32.1836
24238.3.32.184/29238.3.32.185 to 238.3.32.190238.3.32.1916
25238.3.32.192/29238.3.32.193 to 238.3.32.198238.3.32.1996
26238.3.32.200/29238.3.32.201 to 238.3.32.206238.3.32.2076
27238.3.32.208/29238.3.32.209 to 238.3.32.214238.3.32.2156
28238.3.32.216/29238.3.32.217 to 238.3.32.222238.3.32.2236
29238.3.32.224/29238.3.32.225 to 238.3.32.230238.3.32.2316
30238.3.32.232/29238.3.32.233 to 238.3.32.238238.3.32.2396
31238.3.32.240/29238.3.32.241 to 238.3.32.246238.3.32.2476
32238.3.32.248/29238.3.32.249 to 238.3.32.254238.3.32.2556
33238.3.33.0/29238.3.33.1 to 238.3.33.6238.3.33.76
34238.3.33.8/29238.3.33.9 to 238.3.33.14238.3.33.156
35238.3.33.16/29238.3.33.17 to 238.3.33.22238.3.33.236
36238.3.33.24/29238.3.33.25 to 238.3.33.30238.3.33.316
37238.3.33.32/29238.3.33.33 to 238.3.33.38238.3.33.396
38238.3.33.40/29238.3.33.41 to 238.3.33.46238.3.33.476
39238.3.33.48/29238.3.33.49 to 238.3.33.54238.3.33.556
40238.3.33.56/29238.3.33.57 to 238.3.33.62238.3.33.636
41238.3.33.64/29238.3.33.65 to 238.3.33.70238.3.33.716
42238.3.33.72/29238.3.33.73 to 238.3.33.78238.3.33.796
43238.3.33.80/29238.3.33.81 to 238.3.33.86238.3.33.876
44238.3.33.88/29238.3.33.89 to 238.3.33.94238.3.33.956
45238.3.33.96/29238.3.33.97 to 238.3.33.102238.3.33.1036
46238.3.33.104/29238.3.33.105 to 238.3.33.110238.3.33.1116
47238.3.33.112/29238.3.33.113 to 238.3.33.118238.3.33.1196
48238.3.33.120/29238.3.33.121 to 238.3.33.126238.3.33.1276
49238.3.33.128/29238.3.33.129 to 238.3.33.134238.3.33.1356
50238.3.33.136/29238.3.33.137 to 238.3.33.142238.3.33.1436
51238.3.33.144/29238.3.33.145 to 238.3.33.150238.3.33.1516
52238.3.33.152/29238.3.33.153 to 238.3.33.158238.3.33.1596
53238.3.33.160/29238.3.33.161 to 238.3.33.166238.3.33.1676
54238.3.33.168/29238.3.33.169 to 238.3.33.174238.3.33.1756
55238.3.33.176/29238.3.33.177 to 238.3.33.182238.3.33.1836
56238.3.33.184/29238.3.33.185 to 238.3.33.190238.3.33.1916
57238.3.33.192/29238.3.33.193 to 238.3.33.198238.3.33.1996
58238.3.33.200/29238.3.33.201 to 238.3.33.206238.3.33.2076
59238.3.33.208/29238.3.33.209 to 238.3.33.214238.3.33.2156
60238.3.33.216/29238.3.33.217 to 238.3.33.222238.3.33.2236
61238.3.33.224/29238.3.33.225 to 238.3.33.230238.3.33.2316
62238.3.33.232/29238.3.33.233 to 238.3.33.238238.3.33.2396
63238.3.33.240/29238.3.33.241 to 238.3.33.246238.3.33.2476
64238.3.33.248/29238.3.33.249 to 238.3.33.254238.3.33.2556
65238.3.34.0/29238.3.34.1 to 238.3.34.6238.3.34.76
66238.3.34.8/29238.3.34.9 to 238.3.34.14238.3.34.156
67238.3.34.16/29238.3.34.17 to 238.3.34.22238.3.34.236
68238.3.34.24/29238.3.34.25 to 238.3.34.30238.3.34.316
69238.3.34.32/29238.3.34.33 to 238.3.34.38238.3.34.396
70238.3.34.40/29238.3.34.41 to 238.3.34.46238.3.34.476
71238.3.34.48/29238.3.34.49 to 238.3.34.54238.3.34.556
72238.3.34.56/29238.3.34.57 to 238.3.34.62238.3.34.636
73238.3.34.64/29238.3.34.65 to 238.3.34.70238.3.34.716
74238.3.34.72/29238.3.34.73 to 238.3.34.78238.3.34.796
75238.3.34.80/29238.3.34.81 to 238.3.34.86238.3.34.876
76238.3.34.88/29238.3.34.89 to 238.3.34.94238.3.34.956
77238.3.34.96/29238.3.34.97 to 238.3.34.102238.3.34.1036
78238.3.34.104/29238.3.34.105 to 238.3.34.110238.3.34.1116
79238.3.34.112/29238.3.34.113 to 238.3.34.118238.3.34.1196
80238.3.34.120/29238.3.34.121 to 238.3.34.126238.3.34.1276
81238.3.34.128/29238.3.34.129 to 238.3.34.134238.3.34.1356
82238.3.34.136/29238.3.34.137 to 238.3.34.142238.3.34.1436
83238.3.34.144/29238.3.34.145 to 238.3.34.150238.3.34.1516
84238.3.34.152/29238.3.34.153 to 238.3.34.158238.3.34.1596
85238.3.34.160/29238.3.34.161 to 238.3.34.166238.3.34.1676
86238.3.34.168/29238.3.34.169 to 238.3.34.174238.3.34.1756
87238.3.34.176/29238.3.34.177 to 238.3.34.182238.3.34.1836
88238.3.34.184/29238.3.34.185 to 238.3.34.190238.3.34.1916
89238.3.34.192/29238.3.34.193 to 238.3.34.198238.3.34.1996
90238.3.34.200/29238.3.34.201 to 238.3.34.206238.3.34.2076
91238.3.34.208/29238.3.34.209 to 238.3.34.214238.3.34.2156
92238.3.34.216/29238.3.34.217 to 238.3.34.222238.3.34.2236
93238.3.34.224/29238.3.34.225 to 238.3.34.230238.3.34.2316
94238.3.34.232/29238.3.34.233 to 238.3.34.238238.3.34.2396
95238.3.34.240/29238.3.34.241 to 238.3.34.246238.3.34.2476
96238.3.34.248/29238.3.34.249 to 238.3.34.254238.3.34.2556
97238.3.35.0/29238.3.35.1 to 238.3.35.6238.3.35.76
98238.3.35.8/29238.3.35.9 to 238.3.35.14238.3.35.156
99238.3.35.16/29238.3.35.17 to 238.3.35.22238.3.35.236
100238.3.35.24/29238.3.35.25 to 238.3.35.30238.3.35.316
101238.3.35.32/29238.3.35.33 to 238.3.35.38238.3.35.396
102238.3.35.40/29238.3.35.41 to 238.3.35.46238.3.35.476
103238.3.35.48/29238.3.35.49 to 238.3.35.54238.3.35.556
104238.3.35.56/29238.3.35.57 to 238.3.35.62238.3.35.636
105238.3.35.64/29238.3.35.65 to 238.3.35.70238.3.35.716
106238.3.35.72/29238.3.35.73 to 238.3.35.78238.3.35.796
107238.3.35.80/29238.3.35.81 to 238.3.35.86238.3.35.876
108238.3.35.88/29238.3.35.89 to 238.3.35.94238.3.35.956
109238.3.35.96/29238.3.35.97 to 238.3.35.102238.3.35.1036
110238.3.35.104/29238.3.35.105 to 238.3.35.110238.3.35.1116
111238.3.35.112/29238.3.35.113 to 238.3.35.118238.3.35.1196
112238.3.35.120/29238.3.35.121 to 238.3.35.126238.3.35.1276
113238.3.35.128/29238.3.35.129 to 238.3.35.134238.3.35.1356
114238.3.35.136/29238.3.35.137 to 238.3.35.142238.3.35.1436
115238.3.35.144/29238.3.35.145 to 238.3.35.150238.3.35.1516
116238.3.35.152/29238.3.35.153 to 238.3.35.158238.3.35.1596
117238.3.35.160/29238.3.35.161 to 238.3.35.166238.3.35.1676
118238.3.35.168/29238.3.35.169 to 238.3.35.174238.3.35.1756
119238.3.35.176/29238.3.35.177 to 238.3.35.182238.3.35.1836
120238.3.35.184/29238.3.35.185 to 238.3.35.190238.3.35.1916
121238.3.35.192/29238.3.35.193 to 238.3.35.198238.3.35.1996
122238.3.35.200/29238.3.35.201 to 238.3.35.206238.3.35.2076
123238.3.35.208/29238.3.35.209 to 238.3.35.214238.3.35.2156
124238.3.35.216/29238.3.35.217 to 238.3.35.222238.3.35.2236
125238.3.35.224/29238.3.35.225 to 238.3.35.230238.3.35.2316
126238.3.35.232/29238.3.35.233 to 238.3.35.238238.3.35.2396
127238.3.35.240/29238.3.35.241 to 238.3.35.246238.3.35.2476
128238.3.35.248/29238.3.35.249 to 238.3.35.254238.3.35.2556
129238.3.36.0/29238.3.36.1 to 238.3.36.6238.3.36.76
130238.3.36.8/29238.3.36.9 to 238.3.36.14238.3.36.156
131238.3.36.16/29238.3.36.17 to 238.3.36.22238.3.36.236
132238.3.36.24/29238.3.36.25 to 238.3.36.30238.3.36.316
133238.3.36.32/29238.3.36.33 to 238.3.36.38238.3.36.396
134238.3.36.40/29238.3.36.41 to 238.3.36.46238.3.36.476
135238.3.36.48/29238.3.36.49 to 238.3.36.54238.3.36.556
136238.3.36.56/29238.3.36.57 to 238.3.36.62238.3.36.636
137238.3.36.64/29238.3.36.65 to 238.3.36.70238.3.36.716
138238.3.36.72/29238.3.36.73 to 238.3.36.78238.3.36.796
139238.3.36.80/29238.3.36.81 to 238.3.36.86238.3.36.876
140238.3.36.88/29238.3.36.89 to 238.3.36.94238.3.36.956
141238.3.36.96/29238.3.36.97 to 238.3.36.102238.3.36.1036
142238.3.36.104/29238.3.36.105 to 238.3.36.110238.3.36.1116
143238.3.36.112/29238.3.36.113 to 238.3.36.118238.3.36.1196
144238.3.36.120/29238.3.36.121 to 238.3.36.126238.3.36.1276
145238.3.36.128/29238.3.36.129 to 238.3.36.134238.3.36.1356
146238.3.36.136/29238.3.36.137 to 238.3.36.142238.3.36.1436
147238.3.36.144/29238.3.36.145 to 238.3.36.150238.3.36.1516
148238.3.36.152/29238.3.36.153 to 238.3.36.158238.3.36.1596
149238.3.36.160/29238.3.36.161 to 238.3.36.166238.3.36.1676
150238.3.36.168/29238.3.36.169 to 238.3.36.174238.3.36.1756
151238.3.36.176/29238.3.36.177 to 238.3.36.182238.3.36.1836
152238.3.36.184/29238.3.36.185 to 238.3.36.190238.3.36.1916
153238.3.36.192/29238.3.36.193 to 238.3.36.198238.3.36.1996
154238.3.36.200/29238.3.36.201 to 238.3.36.206238.3.36.2076
155238.3.36.208/29238.3.36.209 to 238.3.36.214238.3.36.2156
156238.3.36.216/29238.3.36.217 to 238.3.36.222238.3.36.2236
157238.3.36.224/29238.3.36.225 to 238.3.36.230238.3.36.2316
158238.3.36.232/29238.3.36.233 to 238.3.36.238238.3.36.2396
159238.3.36.240/29238.3.36.241 to 238.3.36.246238.3.36.2476
160238.3.36.248/29238.3.36.249 to 238.3.36.254238.3.36.2556
161238.3.37.0/29238.3.37.1 to 238.3.37.6238.3.37.76
162238.3.37.8/29238.3.37.9 to 238.3.37.14238.3.37.156
163238.3.37.16/29238.3.37.17 to 238.3.37.22238.3.37.236
164238.3.37.24/29238.3.37.25 to 238.3.37.30238.3.37.316
165238.3.37.32/29238.3.37.33 to 238.3.37.38238.3.37.396
166238.3.37.40/29238.3.37.41 to 238.3.37.46238.3.37.476
167238.3.37.48/29238.3.37.49 to 238.3.37.54238.3.37.556
168238.3.37.56/29238.3.37.57 to 238.3.37.62238.3.37.636
169238.3.37.64/29238.3.37.65 to 238.3.37.70238.3.37.716
170238.3.37.72/29238.3.37.73 to 238.3.37.78238.3.37.796
171238.3.37.80/29238.3.37.81 to 238.3.37.86238.3.37.876
172238.3.37.88/29238.3.37.89 to 238.3.37.94238.3.37.956
173238.3.37.96/29238.3.37.97 to 238.3.37.102238.3.37.1036
174238.3.37.104/29238.3.37.105 to 238.3.37.110238.3.37.1116
175238.3.37.112/29238.3.37.113 to 238.3.37.118238.3.37.1196
176238.3.37.120/29238.3.37.121 to 238.3.37.126238.3.37.1276
177238.3.37.128/29238.3.37.129 to 238.3.37.134238.3.37.1356
178238.3.37.136/29238.3.37.137 to 238.3.37.142238.3.37.1436
179238.3.37.144/29238.3.37.145 to 238.3.37.150238.3.37.1516
180238.3.37.152/29238.3.37.153 to 238.3.37.158238.3.37.1596
181238.3.37.160/29238.3.37.161 to 238.3.37.166238.3.37.1676
182238.3.37.168/29238.3.37.169 to 238.3.37.174238.3.37.1756
183238.3.37.176/29238.3.37.177 to 238.3.37.182238.3.37.1836
184238.3.37.184/29238.3.37.185 to 238.3.37.190238.3.37.1916
185238.3.37.192/29238.3.37.193 to 238.3.37.198238.3.37.1996
186238.3.37.200/29238.3.37.201 to 238.3.37.206238.3.37.2076
187238.3.37.208/29238.3.37.209 to 238.3.37.214238.3.37.2156
188238.3.37.216/29238.3.37.217 to 238.3.37.222238.3.37.2236
189238.3.37.224/29238.3.37.225 to 238.3.37.230238.3.37.2316
190238.3.37.232/29238.3.37.233 to 238.3.37.238238.3.37.2396
191238.3.37.240/29238.3.37.241 to 238.3.37.246238.3.37.2476
192238.3.37.248/29238.3.37.249 to 238.3.37.254238.3.37.2556
193238.3.38.0/29238.3.38.1 to 238.3.38.6238.3.38.76
194238.3.38.8/29238.3.38.9 to 238.3.38.14238.3.38.156
195238.3.38.16/29238.3.38.17 to 238.3.38.22238.3.38.236
196238.3.38.24/29238.3.38.25 to 238.3.38.30238.3.38.316
197238.3.38.32/29238.3.38.33 to 238.3.38.38238.3.38.396
198238.3.38.40/29238.3.38.41 to 238.3.38.46238.3.38.476
199238.3.38.48/29238.3.38.49 to 238.3.38.54238.3.38.556
200238.3.38.56/29238.3.38.57 to 238.3.38.62238.3.38.636
201238.3.38.64/29238.3.38.65 to 238.3.38.70238.3.38.716
202238.3.38.72/29238.3.38.73 to 238.3.38.78238.3.38.796
203238.3.38.80/29238.3.38.81 to 238.3.38.86238.3.38.876
204238.3.38.88/29238.3.38.89 to 238.3.38.94238.3.38.956
205238.3.38.96/29238.3.38.97 to 238.3.38.102238.3.38.1036
206238.3.38.104/29238.3.38.105 to 238.3.38.110238.3.38.1116
207238.3.38.112/29238.3.38.113 to 238.3.38.118238.3.38.1196
208238.3.38.120/29238.3.38.121 to 238.3.38.126238.3.38.1276
209238.3.38.128/29238.3.38.129 to 238.3.38.134238.3.38.1356
210238.3.38.136/29238.3.38.137 to 238.3.38.142238.3.38.1436
211238.3.38.144/29238.3.38.145 to 238.3.38.150238.3.38.1516
212238.3.38.152/29238.3.38.153 to 238.3.38.158238.3.38.1596
213238.3.38.160/29238.3.38.161 to 238.3.38.166238.3.38.1676
214238.3.38.168/29238.3.38.169 to 238.3.38.174238.3.38.1756
215238.3.38.176/29238.3.38.177 to 238.3.38.182238.3.38.1836
216238.3.38.184/29238.3.38.185 to 238.3.38.190238.3.38.1916
217238.3.38.192/29238.3.38.193 to 238.3.38.198238.3.38.1996
218238.3.38.200/29238.3.38.201 to 238.3.38.206238.3.38.2076
219238.3.38.208/29238.3.38.209 to 238.3.38.214238.3.38.2156
220238.3.38.216/29238.3.38.217 to 238.3.38.222238.3.38.2236
221238.3.38.224/29238.3.38.225 to 238.3.38.230238.3.38.2316
222238.3.38.232/29238.3.38.233 to 238.3.38.238238.3.38.2396
223238.3.38.240/29238.3.38.241 to 238.3.38.246238.3.38.2476
224238.3.38.248/29238.3.38.249 to 238.3.38.254238.3.38.2556
225238.3.39.0/29238.3.39.1 to 238.3.39.6238.3.39.76
226238.3.39.8/29238.3.39.9 to 238.3.39.14238.3.39.156
227238.3.39.16/29238.3.39.17 to 238.3.39.22238.3.39.236
228238.3.39.24/29238.3.39.25 to 238.3.39.30238.3.39.316
229238.3.39.32/29238.3.39.33 to 238.3.39.38238.3.39.396
230238.3.39.40/29238.3.39.41 to 238.3.39.46238.3.39.476
231238.3.39.48/29238.3.39.49 to 238.3.39.54238.3.39.556
232238.3.39.56/29238.3.39.57 to 238.3.39.62238.3.39.636
233238.3.39.64/29238.3.39.65 to 238.3.39.70238.3.39.716
234238.3.39.72/29238.3.39.73 to 238.3.39.78238.3.39.796
235238.3.39.80/29238.3.39.81 to 238.3.39.86238.3.39.876
236238.3.39.88/29238.3.39.89 to 238.3.39.94238.3.39.956
237238.3.39.96/29238.3.39.97 to 238.3.39.102238.3.39.1036
238238.3.39.104/29238.3.39.105 to 238.3.39.110238.3.39.1116
239238.3.39.112/29238.3.39.113 to 238.3.39.118238.3.39.1196
240238.3.39.120/29238.3.39.121 to 238.3.39.126238.3.39.1276
241238.3.39.128/29238.3.39.129 to 238.3.39.134238.3.39.1356
242238.3.39.136/29238.3.39.137 to 238.3.39.142238.3.39.1436
243238.3.39.144/29238.3.39.145 to 238.3.39.150238.3.39.1516
244238.3.39.152/29238.3.39.153 to 238.3.39.158238.3.39.1596
245238.3.39.160/29238.3.39.161 to 238.3.39.166238.3.39.1676
246238.3.39.168/29238.3.39.169 to 238.3.39.174238.3.39.1756
247238.3.39.176/29238.3.39.177 to 238.3.39.182238.3.39.1836
248238.3.39.184/29238.3.39.185 to 238.3.39.190238.3.39.1916
249238.3.39.192/29238.3.39.193 to 238.3.39.198238.3.39.1996
250238.3.39.200/29238.3.39.201 to 238.3.39.206238.3.39.2076
251238.3.39.208/29238.3.39.209 to 238.3.39.214238.3.39.2156
252238.3.39.216/29238.3.39.217 to 238.3.39.222238.3.39.2236
253238.3.39.224/29238.3.39.225 to 238.3.39.230238.3.39.2316
254238.3.39.232/29238.3.39.233 to 238.3.39.238238.3.39.2396
255238.3.39.240/29238.3.39.241 to 238.3.39.246238.3.39.2476
256238.3.39.248/29238.3.39.249 to 238.3.39.254238.3.39.2556

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