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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.

Network227.3.32.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
227.3.32.0
Broadcast address
227.3.63.255
First usable
227.3.32.1
Last usable
227.3.63.254
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 E3032000 · Integer 3808632832 to 3808641023
Reverse DNS zones
32.3.227.in-addr.arpa
33.3.227.in-addr.arpa
34.3.227.in-addr.arpa
35.3.227.in-addr.arpa
36.3.227.in-addr.arpa
37.3.227.in-addr.arpa
38.3.227.in-addr.arpa
39.3.227.in-addr.arpa
40.3.227.in-addr.arpa
41.3.227.in-addr.arpa
42.3.227.in-addr.arpa
43.3.227.in-addr.arpa
44.3.227.in-addr.arpa
45.3.227.in-addr.arpa
46.3.227.in-addr.arpa
47.3.227.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
Address11100011.00000011.00100000.00000000227.3.32.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network11100011.00000011.00100000.00000000227.3.32.0
Broadcast11100011.00000011.00111111.11111111227.3.63.255
Split into smaller subnets/27

227.3.32.0/19 makes 256 subnets of /27.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1227.3.32.0/27227.3.32.1 to 227.3.32.30227.3.32.3130
2227.3.32.32/27227.3.32.33 to 227.3.32.62227.3.32.6330
3227.3.32.64/27227.3.32.65 to 227.3.32.94227.3.32.9530
4227.3.32.96/27227.3.32.97 to 227.3.32.126227.3.32.12730
5227.3.32.128/27227.3.32.129 to 227.3.32.158227.3.32.15930
6227.3.32.160/27227.3.32.161 to 227.3.32.190227.3.32.19130
7227.3.32.192/27227.3.32.193 to 227.3.32.222227.3.32.22330
8227.3.32.224/27227.3.32.225 to 227.3.32.254227.3.32.25530
9227.3.33.0/27227.3.33.1 to 227.3.33.30227.3.33.3130
10227.3.33.32/27227.3.33.33 to 227.3.33.62227.3.33.6330
11227.3.33.64/27227.3.33.65 to 227.3.33.94227.3.33.9530
12227.3.33.96/27227.3.33.97 to 227.3.33.126227.3.33.12730
13227.3.33.128/27227.3.33.129 to 227.3.33.158227.3.33.15930
14227.3.33.160/27227.3.33.161 to 227.3.33.190227.3.33.19130
15227.3.33.192/27227.3.33.193 to 227.3.33.222227.3.33.22330
16227.3.33.224/27227.3.33.225 to 227.3.33.254227.3.33.25530
17227.3.34.0/27227.3.34.1 to 227.3.34.30227.3.34.3130
18227.3.34.32/27227.3.34.33 to 227.3.34.62227.3.34.6330
19227.3.34.64/27227.3.34.65 to 227.3.34.94227.3.34.9530
20227.3.34.96/27227.3.34.97 to 227.3.34.126227.3.34.12730
21227.3.34.128/27227.3.34.129 to 227.3.34.158227.3.34.15930
22227.3.34.160/27227.3.34.161 to 227.3.34.190227.3.34.19130
23227.3.34.192/27227.3.34.193 to 227.3.34.222227.3.34.22330
24227.3.34.224/27227.3.34.225 to 227.3.34.254227.3.34.25530
25227.3.35.0/27227.3.35.1 to 227.3.35.30227.3.35.3130
26227.3.35.32/27227.3.35.33 to 227.3.35.62227.3.35.6330
27227.3.35.64/27227.3.35.65 to 227.3.35.94227.3.35.9530
28227.3.35.96/27227.3.35.97 to 227.3.35.126227.3.35.12730
29227.3.35.128/27227.3.35.129 to 227.3.35.158227.3.35.15930
30227.3.35.160/27227.3.35.161 to 227.3.35.190227.3.35.19130
31227.3.35.192/27227.3.35.193 to 227.3.35.222227.3.35.22330
32227.3.35.224/27227.3.35.225 to 227.3.35.254227.3.35.25530
33227.3.36.0/27227.3.36.1 to 227.3.36.30227.3.36.3130
34227.3.36.32/27227.3.36.33 to 227.3.36.62227.3.36.6330
35227.3.36.64/27227.3.36.65 to 227.3.36.94227.3.36.9530
36227.3.36.96/27227.3.36.97 to 227.3.36.126227.3.36.12730
37227.3.36.128/27227.3.36.129 to 227.3.36.158227.3.36.15930
38227.3.36.160/27227.3.36.161 to 227.3.36.190227.3.36.19130
39227.3.36.192/27227.3.36.193 to 227.3.36.222227.3.36.22330
40227.3.36.224/27227.3.36.225 to 227.3.36.254227.3.36.25530
41227.3.37.0/27227.3.37.1 to 227.3.37.30227.3.37.3130
42227.3.37.32/27227.3.37.33 to 227.3.37.62227.3.37.6330
43227.3.37.64/27227.3.37.65 to 227.3.37.94227.3.37.9530
44227.3.37.96/27227.3.37.97 to 227.3.37.126227.3.37.12730
45227.3.37.128/27227.3.37.129 to 227.3.37.158227.3.37.15930
46227.3.37.160/27227.3.37.161 to 227.3.37.190227.3.37.19130
47227.3.37.192/27227.3.37.193 to 227.3.37.222227.3.37.22330
48227.3.37.224/27227.3.37.225 to 227.3.37.254227.3.37.25530
49227.3.38.0/27227.3.38.1 to 227.3.38.30227.3.38.3130
50227.3.38.32/27227.3.38.33 to 227.3.38.62227.3.38.6330
51227.3.38.64/27227.3.38.65 to 227.3.38.94227.3.38.9530
52227.3.38.96/27227.3.38.97 to 227.3.38.126227.3.38.12730
53227.3.38.128/27227.3.38.129 to 227.3.38.158227.3.38.15930
54227.3.38.160/27227.3.38.161 to 227.3.38.190227.3.38.19130
55227.3.38.192/27227.3.38.193 to 227.3.38.222227.3.38.22330
56227.3.38.224/27227.3.38.225 to 227.3.38.254227.3.38.25530
57227.3.39.0/27227.3.39.1 to 227.3.39.30227.3.39.3130
58227.3.39.32/27227.3.39.33 to 227.3.39.62227.3.39.6330
59227.3.39.64/27227.3.39.65 to 227.3.39.94227.3.39.9530
60227.3.39.96/27227.3.39.97 to 227.3.39.126227.3.39.12730
61227.3.39.128/27227.3.39.129 to 227.3.39.158227.3.39.15930
62227.3.39.160/27227.3.39.161 to 227.3.39.190227.3.39.19130
63227.3.39.192/27227.3.39.193 to 227.3.39.222227.3.39.22330
64227.3.39.224/27227.3.39.225 to 227.3.39.254227.3.39.25530
65227.3.40.0/27227.3.40.1 to 227.3.40.30227.3.40.3130
66227.3.40.32/27227.3.40.33 to 227.3.40.62227.3.40.6330
67227.3.40.64/27227.3.40.65 to 227.3.40.94227.3.40.9530
68227.3.40.96/27227.3.40.97 to 227.3.40.126227.3.40.12730
69227.3.40.128/27227.3.40.129 to 227.3.40.158227.3.40.15930
70227.3.40.160/27227.3.40.161 to 227.3.40.190227.3.40.19130
71227.3.40.192/27227.3.40.193 to 227.3.40.222227.3.40.22330
72227.3.40.224/27227.3.40.225 to 227.3.40.254227.3.40.25530
73227.3.41.0/27227.3.41.1 to 227.3.41.30227.3.41.3130
74227.3.41.32/27227.3.41.33 to 227.3.41.62227.3.41.6330
75227.3.41.64/27227.3.41.65 to 227.3.41.94227.3.41.9530
76227.3.41.96/27227.3.41.97 to 227.3.41.126227.3.41.12730
77227.3.41.128/27227.3.41.129 to 227.3.41.158227.3.41.15930
78227.3.41.160/27227.3.41.161 to 227.3.41.190227.3.41.19130
79227.3.41.192/27227.3.41.193 to 227.3.41.222227.3.41.22330
80227.3.41.224/27227.3.41.225 to 227.3.41.254227.3.41.25530
81227.3.42.0/27227.3.42.1 to 227.3.42.30227.3.42.3130
82227.3.42.32/27227.3.42.33 to 227.3.42.62227.3.42.6330
83227.3.42.64/27227.3.42.65 to 227.3.42.94227.3.42.9530
84227.3.42.96/27227.3.42.97 to 227.3.42.126227.3.42.12730
85227.3.42.128/27227.3.42.129 to 227.3.42.158227.3.42.15930
86227.3.42.160/27227.3.42.161 to 227.3.42.190227.3.42.19130
87227.3.42.192/27227.3.42.193 to 227.3.42.222227.3.42.22330
88227.3.42.224/27227.3.42.225 to 227.3.42.254227.3.42.25530
89227.3.43.0/27227.3.43.1 to 227.3.43.30227.3.43.3130
90227.3.43.32/27227.3.43.33 to 227.3.43.62227.3.43.6330
91227.3.43.64/27227.3.43.65 to 227.3.43.94227.3.43.9530
92227.3.43.96/27227.3.43.97 to 227.3.43.126227.3.43.12730
93227.3.43.128/27227.3.43.129 to 227.3.43.158227.3.43.15930
94227.3.43.160/27227.3.43.161 to 227.3.43.190227.3.43.19130
95227.3.43.192/27227.3.43.193 to 227.3.43.222227.3.43.22330
96227.3.43.224/27227.3.43.225 to 227.3.43.254227.3.43.25530
97227.3.44.0/27227.3.44.1 to 227.3.44.30227.3.44.3130
98227.3.44.32/27227.3.44.33 to 227.3.44.62227.3.44.6330
99227.3.44.64/27227.3.44.65 to 227.3.44.94227.3.44.9530
100227.3.44.96/27227.3.44.97 to 227.3.44.126227.3.44.12730
101227.3.44.128/27227.3.44.129 to 227.3.44.158227.3.44.15930
102227.3.44.160/27227.3.44.161 to 227.3.44.190227.3.44.19130
103227.3.44.192/27227.3.44.193 to 227.3.44.222227.3.44.22330
104227.3.44.224/27227.3.44.225 to 227.3.44.254227.3.44.25530
105227.3.45.0/27227.3.45.1 to 227.3.45.30227.3.45.3130
106227.3.45.32/27227.3.45.33 to 227.3.45.62227.3.45.6330
107227.3.45.64/27227.3.45.65 to 227.3.45.94227.3.45.9530
108227.3.45.96/27227.3.45.97 to 227.3.45.126227.3.45.12730
109227.3.45.128/27227.3.45.129 to 227.3.45.158227.3.45.15930
110227.3.45.160/27227.3.45.161 to 227.3.45.190227.3.45.19130
111227.3.45.192/27227.3.45.193 to 227.3.45.222227.3.45.22330
112227.3.45.224/27227.3.45.225 to 227.3.45.254227.3.45.25530
113227.3.46.0/27227.3.46.1 to 227.3.46.30227.3.46.3130
114227.3.46.32/27227.3.46.33 to 227.3.46.62227.3.46.6330
115227.3.46.64/27227.3.46.65 to 227.3.46.94227.3.46.9530
116227.3.46.96/27227.3.46.97 to 227.3.46.126227.3.46.12730
117227.3.46.128/27227.3.46.129 to 227.3.46.158227.3.46.15930
118227.3.46.160/27227.3.46.161 to 227.3.46.190227.3.46.19130
119227.3.46.192/27227.3.46.193 to 227.3.46.222227.3.46.22330
120227.3.46.224/27227.3.46.225 to 227.3.46.254227.3.46.25530
121227.3.47.0/27227.3.47.1 to 227.3.47.30227.3.47.3130
122227.3.47.32/27227.3.47.33 to 227.3.47.62227.3.47.6330
123227.3.47.64/27227.3.47.65 to 227.3.47.94227.3.47.9530
124227.3.47.96/27227.3.47.97 to 227.3.47.126227.3.47.12730
125227.3.47.128/27227.3.47.129 to 227.3.47.158227.3.47.15930
126227.3.47.160/27227.3.47.161 to 227.3.47.190227.3.47.19130
127227.3.47.192/27227.3.47.193 to 227.3.47.222227.3.47.22330
128227.3.47.224/27227.3.47.225 to 227.3.47.254227.3.47.25530
129227.3.48.0/27227.3.48.1 to 227.3.48.30227.3.48.3130
130227.3.48.32/27227.3.48.33 to 227.3.48.62227.3.48.6330
131227.3.48.64/27227.3.48.65 to 227.3.48.94227.3.48.9530
132227.3.48.96/27227.3.48.97 to 227.3.48.126227.3.48.12730
133227.3.48.128/27227.3.48.129 to 227.3.48.158227.3.48.15930
134227.3.48.160/27227.3.48.161 to 227.3.48.190227.3.48.19130
135227.3.48.192/27227.3.48.193 to 227.3.48.222227.3.48.22330
136227.3.48.224/27227.3.48.225 to 227.3.48.254227.3.48.25530
137227.3.49.0/27227.3.49.1 to 227.3.49.30227.3.49.3130
138227.3.49.32/27227.3.49.33 to 227.3.49.62227.3.49.6330
139227.3.49.64/27227.3.49.65 to 227.3.49.94227.3.49.9530
140227.3.49.96/27227.3.49.97 to 227.3.49.126227.3.49.12730
141227.3.49.128/27227.3.49.129 to 227.3.49.158227.3.49.15930
142227.3.49.160/27227.3.49.161 to 227.3.49.190227.3.49.19130
143227.3.49.192/27227.3.49.193 to 227.3.49.222227.3.49.22330
144227.3.49.224/27227.3.49.225 to 227.3.49.254227.3.49.25530
145227.3.50.0/27227.3.50.1 to 227.3.50.30227.3.50.3130
146227.3.50.32/27227.3.50.33 to 227.3.50.62227.3.50.6330
147227.3.50.64/27227.3.50.65 to 227.3.50.94227.3.50.9530
148227.3.50.96/27227.3.50.97 to 227.3.50.126227.3.50.12730
149227.3.50.128/27227.3.50.129 to 227.3.50.158227.3.50.15930
150227.3.50.160/27227.3.50.161 to 227.3.50.190227.3.50.19130
151227.3.50.192/27227.3.50.193 to 227.3.50.222227.3.50.22330
152227.3.50.224/27227.3.50.225 to 227.3.50.254227.3.50.25530
153227.3.51.0/27227.3.51.1 to 227.3.51.30227.3.51.3130
154227.3.51.32/27227.3.51.33 to 227.3.51.62227.3.51.6330
155227.3.51.64/27227.3.51.65 to 227.3.51.94227.3.51.9530
156227.3.51.96/27227.3.51.97 to 227.3.51.126227.3.51.12730
157227.3.51.128/27227.3.51.129 to 227.3.51.158227.3.51.15930
158227.3.51.160/27227.3.51.161 to 227.3.51.190227.3.51.19130
159227.3.51.192/27227.3.51.193 to 227.3.51.222227.3.51.22330
160227.3.51.224/27227.3.51.225 to 227.3.51.254227.3.51.25530
161227.3.52.0/27227.3.52.1 to 227.3.52.30227.3.52.3130
162227.3.52.32/27227.3.52.33 to 227.3.52.62227.3.52.6330
163227.3.52.64/27227.3.52.65 to 227.3.52.94227.3.52.9530
164227.3.52.96/27227.3.52.97 to 227.3.52.126227.3.52.12730
165227.3.52.128/27227.3.52.129 to 227.3.52.158227.3.52.15930
166227.3.52.160/27227.3.52.161 to 227.3.52.190227.3.52.19130
167227.3.52.192/27227.3.52.193 to 227.3.52.222227.3.52.22330
168227.3.52.224/27227.3.52.225 to 227.3.52.254227.3.52.25530
169227.3.53.0/27227.3.53.1 to 227.3.53.30227.3.53.3130
170227.3.53.32/27227.3.53.33 to 227.3.53.62227.3.53.6330
171227.3.53.64/27227.3.53.65 to 227.3.53.94227.3.53.9530
172227.3.53.96/27227.3.53.97 to 227.3.53.126227.3.53.12730
173227.3.53.128/27227.3.53.129 to 227.3.53.158227.3.53.15930
174227.3.53.160/27227.3.53.161 to 227.3.53.190227.3.53.19130
175227.3.53.192/27227.3.53.193 to 227.3.53.222227.3.53.22330
176227.3.53.224/27227.3.53.225 to 227.3.53.254227.3.53.25530
177227.3.54.0/27227.3.54.1 to 227.3.54.30227.3.54.3130
178227.3.54.32/27227.3.54.33 to 227.3.54.62227.3.54.6330
179227.3.54.64/27227.3.54.65 to 227.3.54.94227.3.54.9530
180227.3.54.96/27227.3.54.97 to 227.3.54.126227.3.54.12730
181227.3.54.128/27227.3.54.129 to 227.3.54.158227.3.54.15930
182227.3.54.160/27227.3.54.161 to 227.3.54.190227.3.54.19130
183227.3.54.192/27227.3.54.193 to 227.3.54.222227.3.54.22330
184227.3.54.224/27227.3.54.225 to 227.3.54.254227.3.54.25530
185227.3.55.0/27227.3.55.1 to 227.3.55.30227.3.55.3130
186227.3.55.32/27227.3.55.33 to 227.3.55.62227.3.55.6330
187227.3.55.64/27227.3.55.65 to 227.3.55.94227.3.55.9530
188227.3.55.96/27227.3.55.97 to 227.3.55.126227.3.55.12730
189227.3.55.128/27227.3.55.129 to 227.3.55.158227.3.55.15930
190227.3.55.160/27227.3.55.161 to 227.3.55.190227.3.55.19130
191227.3.55.192/27227.3.55.193 to 227.3.55.222227.3.55.22330
192227.3.55.224/27227.3.55.225 to 227.3.55.254227.3.55.25530
193227.3.56.0/27227.3.56.1 to 227.3.56.30227.3.56.3130
194227.3.56.32/27227.3.56.33 to 227.3.56.62227.3.56.6330
195227.3.56.64/27227.3.56.65 to 227.3.56.94227.3.56.9530
196227.3.56.96/27227.3.56.97 to 227.3.56.126227.3.56.12730
197227.3.56.128/27227.3.56.129 to 227.3.56.158227.3.56.15930
198227.3.56.160/27227.3.56.161 to 227.3.56.190227.3.56.19130
199227.3.56.192/27227.3.56.193 to 227.3.56.222227.3.56.22330
200227.3.56.224/27227.3.56.225 to 227.3.56.254227.3.56.25530
201227.3.57.0/27227.3.57.1 to 227.3.57.30227.3.57.3130
202227.3.57.32/27227.3.57.33 to 227.3.57.62227.3.57.6330
203227.3.57.64/27227.3.57.65 to 227.3.57.94227.3.57.9530
204227.3.57.96/27227.3.57.97 to 227.3.57.126227.3.57.12730
205227.3.57.128/27227.3.57.129 to 227.3.57.158227.3.57.15930
206227.3.57.160/27227.3.57.161 to 227.3.57.190227.3.57.19130
207227.3.57.192/27227.3.57.193 to 227.3.57.222227.3.57.22330
208227.3.57.224/27227.3.57.225 to 227.3.57.254227.3.57.25530
209227.3.58.0/27227.3.58.1 to 227.3.58.30227.3.58.3130
210227.3.58.32/27227.3.58.33 to 227.3.58.62227.3.58.6330
211227.3.58.64/27227.3.58.65 to 227.3.58.94227.3.58.9530
212227.3.58.96/27227.3.58.97 to 227.3.58.126227.3.58.12730
213227.3.58.128/27227.3.58.129 to 227.3.58.158227.3.58.15930
214227.3.58.160/27227.3.58.161 to 227.3.58.190227.3.58.19130
215227.3.58.192/27227.3.58.193 to 227.3.58.222227.3.58.22330
216227.3.58.224/27227.3.58.225 to 227.3.58.254227.3.58.25530
217227.3.59.0/27227.3.59.1 to 227.3.59.30227.3.59.3130
218227.3.59.32/27227.3.59.33 to 227.3.59.62227.3.59.6330
219227.3.59.64/27227.3.59.65 to 227.3.59.94227.3.59.9530
220227.3.59.96/27227.3.59.97 to 227.3.59.126227.3.59.12730
221227.3.59.128/27227.3.59.129 to 227.3.59.158227.3.59.15930
222227.3.59.160/27227.3.59.161 to 227.3.59.190227.3.59.19130
223227.3.59.192/27227.3.59.193 to 227.3.59.222227.3.59.22330
224227.3.59.224/27227.3.59.225 to 227.3.59.254227.3.59.25530
225227.3.60.0/27227.3.60.1 to 227.3.60.30227.3.60.3130
226227.3.60.32/27227.3.60.33 to 227.3.60.62227.3.60.6330
227227.3.60.64/27227.3.60.65 to 227.3.60.94227.3.60.9530
228227.3.60.96/27227.3.60.97 to 227.3.60.126227.3.60.12730
229227.3.60.128/27227.3.60.129 to 227.3.60.158227.3.60.15930
230227.3.60.160/27227.3.60.161 to 227.3.60.190227.3.60.19130
231227.3.60.192/27227.3.60.193 to 227.3.60.222227.3.60.22330
232227.3.60.224/27227.3.60.225 to 227.3.60.254227.3.60.25530
233227.3.61.0/27227.3.61.1 to 227.3.61.30227.3.61.3130
234227.3.61.32/27227.3.61.33 to 227.3.61.62227.3.61.6330
235227.3.61.64/27227.3.61.65 to 227.3.61.94227.3.61.9530
236227.3.61.96/27227.3.61.97 to 227.3.61.126227.3.61.12730
237227.3.61.128/27227.3.61.129 to 227.3.61.158227.3.61.15930
238227.3.61.160/27227.3.61.161 to 227.3.61.190227.3.61.19130
239227.3.61.192/27227.3.61.193 to 227.3.61.222227.3.61.22330
240227.3.61.224/27227.3.61.225 to 227.3.61.254227.3.61.25530
241227.3.62.0/27227.3.62.1 to 227.3.62.30227.3.62.3130
242227.3.62.32/27227.3.62.33 to 227.3.62.62227.3.62.6330
243227.3.62.64/27227.3.62.65 to 227.3.62.94227.3.62.9530
244227.3.62.96/27227.3.62.97 to 227.3.62.126227.3.62.12730
245227.3.62.128/27227.3.62.129 to 227.3.62.158227.3.62.15930
246227.3.62.160/27227.3.62.161 to 227.3.62.190227.3.62.19130
247227.3.62.192/27227.3.62.193 to 227.3.62.222227.3.62.22330
248227.3.62.224/27227.3.62.225 to 227.3.62.254227.3.62.25530
249227.3.63.0/27227.3.63.1 to 227.3.63.30227.3.63.3130
250227.3.63.32/27227.3.63.33 to 227.3.63.62227.3.63.6330
251227.3.63.64/27227.3.63.65 to 227.3.63.94227.3.63.9530
252227.3.63.96/27227.3.63.97 to 227.3.63.126227.3.63.12730
253227.3.63.128/27227.3.63.129 to 227.3.63.158227.3.63.15930
254227.3.63.160/27227.3.63.161 to 227.3.63.190227.3.63.19130
255227.3.63.192/27227.3.63.193 to 227.3.63.222227.3.63.22330
256227.3.63.224/27227.3.63.225 to 227.3.63.254227.3.63.25530

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