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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.

Network229.44.64.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
229.44.64.0
Broadcast address
229.44.95.255
First usable
229.44.64.1
Last usable
229.44.95.254
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 E52C4000 · Integer 3844882432 to 3844890623
Reverse DNS zones
64.44.229.in-addr.arpa
65.44.229.in-addr.arpa
66.44.229.in-addr.arpa
67.44.229.in-addr.arpa
68.44.229.in-addr.arpa
69.44.229.in-addr.arpa
70.44.229.in-addr.arpa
71.44.229.in-addr.arpa
72.44.229.in-addr.arpa
73.44.229.in-addr.arpa
74.44.229.in-addr.arpa
75.44.229.in-addr.arpa
76.44.229.in-addr.arpa
77.44.229.in-addr.arpa
78.44.229.in-addr.arpa
79.44.229.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
Address11100101.00101100.01000000.00000000229.44.64.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network11100101.00101100.01000000.00000000229.44.64.0
Broadcast11100101.00101100.01011111.11111111229.44.95.255
Split into smaller subnets/28
/20 (2)/21 (4)/22 (8)/23 (16)/24 (32)/25 (64)/26 (128)/27 (256)/28 (512)/29 (1,024)/30 (2,048)/31 (4,096)

229.44.64.0/19 makes 512 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1229.44.64.0/28229.44.64.1 to 229.44.64.14229.44.64.1514
2229.44.64.16/28229.44.64.17 to 229.44.64.30229.44.64.3114
3229.44.64.32/28229.44.64.33 to 229.44.64.46229.44.64.4714
4229.44.64.48/28229.44.64.49 to 229.44.64.62229.44.64.6314
5229.44.64.64/28229.44.64.65 to 229.44.64.78229.44.64.7914
6229.44.64.80/28229.44.64.81 to 229.44.64.94229.44.64.9514
7229.44.64.96/28229.44.64.97 to 229.44.64.110229.44.64.11114
8229.44.64.112/28229.44.64.113 to 229.44.64.126229.44.64.12714
9229.44.64.128/28229.44.64.129 to 229.44.64.142229.44.64.14314
10229.44.64.144/28229.44.64.145 to 229.44.64.158229.44.64.15914
11229.44.64.160/28229.44.64.161 to 229.44.64.174229.44.64.17514
12229.44.64.176/28229.44.64.177 to 229.44.64.190229.44.64.19114
13229.44.64.192/28229.44.64.193 to 229.44.64.206229.44.64.20714
14229.44.64.208/28229.44.64.209 to 229.44.64.222229.44.64.22314
15229.44.64.224/28229.44.64.225 to 229.44.64.238229.44.64.23914
16229.44.64.240/28229.44.64.241 to 229.44.64.254229.44.64.25514
17229.44.65.0/28229.44.65.1 to 229.44.65.14229.44.65.1514
18229.44.65.16/28229.44.65.17 to 229.44.65.30229.44.65.3114
19229.44.65.32/28229.44.65.33 to 229.44.65.46229.44.65.4714
20229.44.65.48/28229.44.65.49 to 229.44.65.62229.44.65.6314
21229.44.65.64/28229.44.65.65 to 229.44.65.78229.44.65.7914
22229.44.65.80/28229.44.65.81 to 229.44.65.94229.44.65.9514
23229.44.65.96/28229.44.65.97 to 229.44.65.110229.44.65.11114
24229.44.65.112/28229.44.65.113 to 229.44.65.126229.44.65.12714
25229.44.65.128/28229.44.65.129 to 229.44.65.142229.44.65.14314
26229.44.65.144/28229.44.65.145 to 229.44.65.158229.44.65.15914
27229.44.65.160/28229.44.65.161 to 229.44.65.174229.44.65.17514
28229.44.65.176/28229.44.65.177 to 229.44.65.190229.44.65.19114
29229.44.65.192/28229.44.65.193 to 229.44.65.206229.44.65.20714
30229.44.65.208/28229.44.65.209 to 229.44.65.222229.44.65.22314
31229.44.65.224/28229.44.65.225 to 229.44.65.238229.44.65.23914
32229.44.65.240/28229.44.65.241 to 229.44.65.254229.44.65.25514
33229.44.66.0/28229.44.66.1 to 229.44.66.14229.44.66.1514
34229.44.66.16/28229.44.66.17 to 229.44.66.30229.44.66.3114
35229.44.66.32/28229.44.66.33 to 229.44.66.46229.44.66.4714
36229.44.66.48/28229.44.66.49 to 229.44.66.62229.44.66.6314
37229.44.66.64/28229.44.66.65 to 229.44.66.78229.44.66.7914
38229.44.66.80/28229.44.66.81 to 229.44.66.94229.44.66.9514
39229.44.66.96/28229.44.66.97 to 229.44.66.110229.44.66.11114
40229.44.66.112/28229.44.66.113 to 229.44.66.126229.44.66.12714
41229.44.66.128/28229.44.66.129 to 229.44.66.142229.44.66.14314
42229.44.66.144/28229.44.66.145 to 229.44.66.158229.44.66.15914
43229.44.66.160/28229.44.66.161 to 229.44.66.174229.44.66.17514
44229.44.66.176/28229.44.66.177 to 229.44.66.190229.44.66.19114
45229.44.66.192/28229.44.66.193 to 229.44.66.206229.44.66.20714
46229.44.66.208/28229.44.66.209 to 229.44.66.222229.44.66.22314
47229.44.66.224/28229.44.66.225 to 229.44.66.238229.44.66.23914
48229.44.66.240/28229.44.66.241 to 229.44.66.254229.44.66.25514
49229.44.67.0/28229.44.67.1 to 229.44.67.14229.44.67.1514
50229.44.67.16/28229.44.67.17 to 229.44.67.30229.44.67.3114
51229.44.67.32/28229.44.67.33 to 229.44.67.46229.44.67.4714
52229.44.67.48/28229.44.67.49 to 229.44.67.62229.44.67.6314
53229.44.67.64/28229.44.67.65 to 229.44.67.78229.44.67.7914
54229.44.67.80/28229.44.67.81 to 229.44.67.94229.44.67.9514
55229.44.67.96/28229.44.67.97 to 229.44.67.110229.44.67.11114
56229.44.67.112/28229.44.67.113 to 229.44.67.126229.44.67.12714
57229.44.67.128/28229.44.67.129 to 229.44.67.142229.44.67.14314
58229.44.67.144/28229.44.67.145 to 229.44.67.158229.44.67.15914
59229.44.67.160/28229.44.67.161 to 229.44.67.174229.44.67.17514
60229.44.67.176/28229.44.67.177 to 229.44.67.190229.44.67.19114
61229.44.67.192/28229.44.67.193 to 229.44.67.206229.44.67.20714
62229.44.67.208/28229.44.67.209 to 229.44.67.222229.44.67.22314
63229.44.67.224/28229.44.67.225 to 229.44.67.238229.44.67.23914
64229.44.67.240/28229.44.67.241 to 229.44.67.254229.44.67.25514
65229.44.68.0/28229.44.68.1 to 229.44.68.14229.44.68.1514
66229.44.68.16/28229.44.68.17 to 229.44.68.30229.44.68.3114
67229.44.68.32/28229.44.68.33 to 229.44.68.46229.44.68.4714
68229.44.68.48/28229.44.68.49 to 229.44.68.62229.44.68.6314
69229.44.68.64/28229.44.68.65 to 229.44.68.78229.44.68.7914
70229.44.68.80/28229.44.68.81 to 229.44.68.94229.44.68.9514
71229.44.68.96/28229.44.68.97 to 229.44.68.110229.44.68.11114
72229.44.68.112/28229.44.68.113 to 229.44.68.126229.44.68.12714
73229.44.68.128/28229.44.68.129 to 229.44.68.142229.44.68.14314
74229.44.68.144/28229.44.68.145 to 229.44.68.158229.44.68.15914
75229.44.68.160/28229.44.68.161 to 229.44.68.174229.44.68.17514
76229.44.68.176/28229.44.68.177 to 229.44.68.190229.44.68.19114
77229.44.68.192/28229.44.68.193 to 229.44.68.206229.44.68.20714
78229.44.68.208/28229.44.68.209 to 229.44.68.222229.44.68.22314
79229.44.68.224/28229.44.68.225 to 229.44.68.238229.44.68.23914
80229.44.68.240/28229.44.68.241 to 229.44.68.254229.44.68.25514
81229.44.69.0/28229.44.69.1 to 229.44.69.14229.44.69.1514
82229.44.69.16/28229.44.69.17 to 229.44.69.30229.44.69.3114
83229.44.69.32/28229.44.69.33 to 229.44.69.46229.44.69.4714
84229.44.69.48/28229.44.69.49 to 229.44.69.62229.44.69.6314
85229.44.69.64/28229.44.69.65 to 229.44.69.78229.44.69.7914
86229.44.69.80/28229.44.69.81 to 229.44.69.94229.44.69.9514
87229.44.69.96/28229.44.69.97 to 229.44.69.110229.44.69.11114
88229.44.69.112/28229.44.69.113 to 229.44.69.126229.44.69.12714
89229.44.69.128/28229.44.69.129 to 229.44.69.142229.44.69.14314
90229.44.69.144/28229.44.69.145 to 229.44.69.158229.44.69.15914
91229.44.69.160/28229.44.69.161 to 229.44.69.174229.44.69.17514
92229.44.69.176/28229.44.69.177 to 229.44.69.190229.44.69.19114
93229.44.69.192/28229.44.69.193 to 229.44.69.206229.44.69.20714
94229.44.69.208/28229.44.69.209 to 229.44.69.222229.44.69.22314
95229.44.69.224/28229.44.69.225 to 229.44.69.238229.44.69.23914
96229.44.69.240/28229.44.69.241 to 229.44.69.254229.44.69.25514
97229.44.70.0/28229.44.70.1 to 229.44.70.14229.44.70.1514
98229.44.70.16/28229.44.70.17 to 229.44.70.30229.44.70.3114
99229.44.70.32/28229.44.70.33 to 229.44.70.46229.44.70.4714
100229.44.70.48/28229.44.70.49 to 229.44.70.62229.44.70.6314
101229.44.70.64/28229.44.70.65 to 229.44.70.78229.44.70.7914
102229.44.70.80/28229.44.70.81 to 229.44.70.94229.44.70.9514
103229.44.70.96/28229.44.70.97 to 229.44.70.110229.44.70.11114
104229.44.70.112/28229.44.70.113 to 229.44.70.126229.44.70.12714
105229.44.70.128/28229.44.70.129 to 229.44.70.142229.44.70.14314
106229.44.70.144/28229.44.70.145 to 229.44.70.158229.44.70.15914
107229.44.70.160/28229.44.70.161 to 229.44.70.174229.44.70.17514
108229.44.70.176/28229.44.70.177 to 229.44.70.190229.44.70.19114
109229.44.70.192/28229.44.70.193 to 229.44.70.206229.44.70.20714
110229.44.70.208/28229.44.70.209 to 229.44.70.222229.44.70.22314
111229.44.70.224/28229.44.70.225 to 229.44.70.238229.44.70.23914
112229.44.70.240/28229.44.70.241 to 229.44.70.254229.44.70.25514
113229.44.71.0/28229.44.71.1 to 229.44.71.14229.44.71.1514
114229.44.71.16/28229.44.71.17 to 229.44.71.30229.44.71.3114
115229.44.71.32/28229.44.71.33 to 229.44.71.46229.44.71.4714
116229.44.71.48/28229.44.71.49 to 229.44.71.62229.44.71.6314
117229.44.71.64/28229.44.71.65 to 229.44.71.78229.44.71.7914
118229.44.71.80/28229.44.71.81 to 229.44.71.94229.44.71.9514
119229.44.71.96/28229.44.71.97 to 229.44.71.110229.44.71.11114
120229.44.71.112/28229.44.71.113 to 229.44.71.126229.44.71.12714
121229.44.71.128/28229.44.71.129 to 229.44.71.142229.44.71.14314
122229.44.71.144/28229.44.71.145 to 229.44.71.158229.44.71.15914
123229.44.71.160/28229.44.71.161 to 229.44.71.174229.44.71.17514
124229.44.71.176/28229.44.71.177 to 229.44.71.190229.44.71.19114
125229.44.71.192/28229.44.71.193 to 229.44.71.206229.44.71.20714
126229.44.71.208/28229.44.71.209 to 229.44.71.222229.44.71.22314
127229.44.71.224/28229.44.71.225 to 229.44.71.238229.44.71.23914
128229.44.71.240/28229.44.71.241 to 229.44.71.254229.44.71.25514
129229.44.72.0/28229.44.72.1 to 229.44.72.14229.44.72.1514
130229.44.72.16/28229.44.72.17 to 229.44.72.30229.44.72.3114
131229.44.72.32/28229.44.72.33 to 229.44.72.46229.44.72.4714
132229.44.72.48/28229.44.72.49 to 229.44.72.62229.44.72.6314
133229.44.72.64/28229.44.72.65 to 229.44.72.78229.44.72.7914
134229.44.72.80/28229.44.72.81 to 229.44.72.94229.44.72.9514
135229.44.72.96/28229.44.72.97 to 229.44.72.110229.44.72.11114
136229.44.72.112/28229.44.72.113 to 229.44.72.126229.44.72.12714
137229.44.72.128/28229.44.72.129 to 229.44.72.142229.44.72.14314
138229.44.72.144/28229.44.72.145 to 229.44.72.158229.44.72.15914
139229.44.72.160/28229.44.72.161 to 229.44.72.174229.44.72.17514
140229.44.72.176/28229.44.72.177 to 229.44.72.190229.44.72.19114
141229.44.72.192/28229.44.72.193 to 229.44.72.206229.44.72.20714
142229.44.72.208/28229.44.72.209 to 229.44.72.222229.44.72.22314
143229.44.72.224/28229.44.72.225 to 229.44.72.238229.44.72.23914
144229.44.72.240/28229.44.72.241 to 229.44.72.254229.44.72.25514
145229.44.73.0/28229.44.73.1 to 229.44.73.14229.44.73.1514
146229.44.73.16/28229.44.73.17 to 229.44.73.30229.44.73.3114
147229.44.73.32/28229.44.73.33 to 229.44.73.46229.44.73.4714
148229.44.73.48/28229.44.73.49 to 229.44.73.62229.44.73.6314
149229.44.73.64/28229.44.73.65 to 229.44.73.78229.44.73.7914
150229.44.73.80/28229.44.73.81 to 229.44.73.94229.44.73.9514
151229.44.73.96/28229.44.73.97 to 229.44.73.110229.44.73.11114
152229.44.73.112/28229.44.73.113 to 229.44.73.126229.44.73.12714
153229.44.73.128/28229.44.73.129 to 229.44.73.142229.44.73.14314
154229.44.73.144/28229.44.73.145 to 229.44.73.158229.44.73.15914
155229.44.73.160/28229.44.73.161 to 229.44.73.174229.44.73.17514
156229.44.73.176/28229.44.73.177 to 229.44.73.190229.44.73.19114
157229.44.73.192/28229.44.73.193 to 229.44.73.206229.44.73.20714
158229.44.73.208/28229.44.73.209 to 229.44.73.222229.44.73.22314
159229.44.73.224/28229.44.73.225 to 229.44.73.238229.44.73.23914
160229.44.73.240/28229.44.73.241 to 229.44.73.254229.44.73.25514
161229.44.74.0/28229.44.74.1 to 229.44.74.14229.44.74.1514
162229.44.74.16/28229.44.74.17 to 229.44.74.30229.44.74.3114
163229.44.74.32/28229.44.74.33 to 229.44.74.46229.44.74.4714
164229.44.74.48/28229.44.74.49 to 229.44.74.62229.44.74.6314
165229.44.74.64/28229.44.74.65 to 229.44.74.78229.44.74.7914
166229.44.74.80/28229.44.74.81 to 229.44.74.94229.44.74.9514
167229.44.74.96/28229.44.74.97 to 229.44.74.110229.44.74.11114
168229.44.74.112/28229.44.74.113 to 229.44.74.126229.44.74.12714
169229.44.74.128/28229.44.74.129 to 229.44.74.142229.44.74.14314
170229.44.74.144/28229.44.74.145 to 229.44.74.158229.44.74.15914
171229.44.74.160/28229.44.74.161 to 229.44.74.174229.44.74.17514
172229.44.74.176/28229.44.74.177 to 229.44.74.190229.44.74.19114
173229.44.74.192/28229.44.74.193 to 229.44.74.206229.44.74.20714
174229.44.74.208/28229.44.74.209 to 229.44.74.222229.44.74.22314
175229.44.74.224/28229.44.74.225 to 229.44.74.238229.44.74.23914
176229.44.74.240/28229.44.74.241 to 229.44.74.254229.44.74.25514
177229.44.75.0/28229.44.75.1 to 229.44.75.14229.44.75.1514
178229.44.75.16/28229.44.75.17 to 229.44.75.30229.44.75.3114
179229.44.75.32/28229.44.75.33 to 229.44.75.46229.44.75.4714
180229.44.75.48/28229.44.75.49 to 229.44.75.62229.44.75.6314
181229.44.75.64/28229.44.75.65 to 229.44.75.78229.44.75.7914
182229.44.75.80/28229.44.75.81 to 229.44.75.94229.44.75.9514
183229.44.75.96/28229.44.75.97 to 229.44.75.110229.44.75.11114
184229.44.75.112/28229.44.75.113 to 229.44.75.126229.44.75.12714
185229.44.75.128/28229.44.75.129 to 229.44.75.142229.44.75.14314
186229.44.75.144/28229.44.75.145 to 229.44.75.158229.44.75.15914
187229.44.75.160/28229.44.75.161 to 229.44.75.174229.44.75.17514
188229.44.75.176/28229.44.75.177 to 229.44.75.190229.44.75.19114
189229.44.75.192/28229.44.75.193 to 229.44.75.206229.44.75.20714
190229.44.75.208/28229.44.75.209 to 229.44.75.222229.44.75.22314
191229.44.75.224/28229.44.75.225 to 229.44.75.238229.44.75.23914
192229.44.75.240/28229.44.75.241 to 229.44.75.254229.44.75.25514
193229.44.76.0/28229.44.76.1 to 229.44.76.14229.44.76.1514
194229.44.76.16/28229.44.76.17 to 229.44.76.30229.44.76.3114
195229.44.76.32/28229.44.76.33 to 229.44.76.46229.44.76.4714
196229.44.76.48/28229.44.76.49 to 229.44.76.62229.44.76.6314
197229.44.76.64/28229.44.76.65 to 229.44.76.78229.44.76.7914
198229.44.76.80/28229.44.76.81 to 229.44.76.94229.44.76.9514
199229.44.76.96/28229.44.76.97 to 229.44.76.110229.44.76.11114
200229.44.76.112/28229.44.76.113 to 229.44.76.126229.44.76.12714
201229.44.76.128/28229.44.76.129 to 229.44.76.142229.44.76.14314
202229.44.76.144/28229.44.76.145 to 229.44.76.158229.44.76.15914
203229.44.76.160/28229.44.76.161 to 229.44.76.174229.44.76.17514
204229.44.76.176/28229.44.76.177 to 229.44.76.190229.44.76.19114
205229.44.76.192/28229.44.76.193 to 229.44.76.206229.44.76.20714
206229.44.76.208/28229.44.76.209 to 229.44.76.222229.44.76.22314
207229.44.76.224/28229.44.76.225 to 229.44.76.238229.44.76.23914
208229.44.76.240/28229.44.76.241 to 229.44.76.254229.44.76.25514
209229.44.77.0/28229.44.77.1 to 229.44.77.14229.44.77.1514
210229.44.77.16/28229.44.77.17 to 229.44.77.30229.44.77.3114
211229.44.77.32/28229.44.77.33 to 229.44.77.46229.44.77.4714
212229.44.77.48/28229.44.77.49 to 229.44.77.62229.44.77.6314
213229.44.77.64/28229.44.77.65 to 229.44.77.78229.44.77.7914
214229.44.77.80/28229.44.77.81 to 229.44.77.94229.44.77.9514
215229.44.77.96/28229.44.77.97 to 229.44.77.110229.44.77.11114
216229.44.77.112/28229.44.77.113 to 229.44.77.126229.44.77.12714
217229.44.77.128/28229.44.77.129 to 229.44.77.142229.44.77.14314
218229.44.77.144/28229.44.77.145 to 229.44.77.158229.44.77.15914
219229.44.77.160/28229.44.77.161 to 229.44.77.174229.44.77.17514
220229.44.77.176/28229.44.77.177 to 229.44.77.190229.44.77.19114
221229.44.77.192/28229.44.77.193 to 229.44.77.206229.44.77.20714
222229.44.77.208/28229.44.77.209 to 229.44.77.222229.44.77.22314
223229.44.77.224/28229.44.77.225 to 229.44.77.238229.44.77.23914
224229.44.77.240/28229.44.77.241 to 229.44.77.254229.44.77.25514
225229.44.78.0/28229.44.78.1 to 229.44.78.14229.44.78.1514
226229.44.78.16/28229.44.78.17 to 229.44.78.30229.44.78.3114
227229.44.78.32/28229.44.78.33 to 229.44.78.46229.44.78.4714
228229.44.78.48/28229.44.78.49 to 229.44.78.62229.44.78.6314
229229.44.78.64/28229.44.78.65 to 229.44.78.78229.44.78.7914
230229.44.78.80/28229.44.78.81 to 229.44.78.94229.44.78.9514
231229.44.78.96/28229.44.78.97 to 229.44.78.110229.44.78.11114
232229.44.78.112/28229.44.78.113 to 229.44.78.126229.44.78.12714
233229.44.78.128/28229.44.78.129 to 229.44.78.142229.44.78.14314
234229.44.78.144/28229.44.78.145 to 229.44.78.158229.44.78.15914
235229.44.78.160/28229.44.78.161 to 229.44.78.174229.44.78.17514
236229.44.78.176/28229.44.78.177 to 229.44.78.190229.44.78.19114
237229.44.78.192/28229.44.78.193 to 229.44.78.206229.44.78.20714
238229.44.78.208/28229.44.78.209 to 229.44.78.222229.44.78.22314
239229.44.78.224/28229.44.78.225 to 229.44.78.238229.44.78.23914
240229.44.78.240/28229.44.78.241 to 229.44.78.254229.44.78.25514
241229.44.79.0/28229.44.79.1 to 229.44.79.14229.44.79.1514
242229.44.79.16/28229.44.79.17 to 229.44.79.30229.44.79.3114
243229.44.79.32/28229.44.79.33 to 229.44.79.46229.44.79.4714
244229.44.79.48/28229.44.79.49 to 229.44.79.62229.44.79.6314
245229.44.79.64/28229.44.79.65 to 229.44.79.78229.44.79.7914
246229.44.79.80/28229.44.79.81 to 229.44.79.94229.44.79.9514
247229.44.79.96/28229.44.79.97 to 229.44.79.110229.44.79.11114
248229.44.79.112/28229.44.79.113 to 229.44.79.126229.44.79.12714
249229.44.79.128/28229.44.79.129 to 229.44.79.142229.44.79.14314
250229.44.79.144/28229.44.79.145 to 229.44.79.158229.44.79.15914
251229.44.79.160/28229.44.79.161 to 229.44.79.174229.44.79.17514
252229.44.79.176/28229.44.79.177 to 229.44.79.190229.44.79.19114
253229.44.79.192/28229.44.79.193 to 229.44.79.206229.44.79.20714
254229.44.79.208/28229.44.79.209 to 229.44.79.222229.44.79.22314
255229.44.79.224/28229.44.79.225 to 229.44.79.238229.44.79.23914
256229.44.79.240/28229.44.79.241 to 229.44.79.254229.44.79.25514

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

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.