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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.

Network126.2.192.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
126.2.192.0
Broadcast address
126.2.223.255
First usable
126.2.192.1
Last usable
126.2.223.254
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
Public public
Old class
A (default /8)
As numbers
Hex 7E02C000 · Integer 2114109440 to 2114117631
Reverse DNS zones
192.2.126.in-addr.arpa
193.2.126.in-addr.arpa
194.2.126.in-addr.arpa
195.2.126.in-addr.arpa
196.2.126.in-addr.arpa
197.2.126.in-addr.arpa
198.2.126.in-addr.arpa
199.2.126.in-addr.arpa
200.2.126.in-addr.arpa
201.2.126.in-addr.arpa
202.2.126.in-addr.arpa
203.2.126.in-addr.arpa
204.2.126.in-addr.arpa
205.2.126.in-addr.arpa
206.2.126.in-addr.arpa
207.2.126.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
Address01111110.00000010.11000000.00000000126.2.192.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network01111110.00000010.11000000.00000000126.2.192.0
Broadcast01111110.00000010.11011111.11111111126.2.223.255
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)

126.2.192.0/19 makes 512 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1126.2.192.0/28126.2.192.1 to 126.2.192.14126.2.192.1514
2126.2.192.16/28126.2.192.17 to 126.2.192.30126.2.192.3114
3126.2.192.32/28126.2.192.33 to 126.2.192.46126.2.192.4714
4126.2.192.48/28126.2.192.49 to 126.2.192.62126.2.192.6314
5126.2.192.64/28126.2.192.65 to 126.2.192.78126.2.192.7914
6126.2.192.80/28126.2.192.81 to 126.2.192.94126.2.192.9514
7126.2.192.96/28126.2.192.97 to 126.2.192.110126.2.192.11114
8126.2.192.112/28126.2.192.113 to 126.2.192.126126.2.192.12714
9126.2.192.128/28126.2.192.129 to 126.2.192.142126.2.192.14314
10126.2.192.144/28126.2.192.145 to 126.2.192.158126.2.192.15914
11126.2.192.160/28126.2.192.161 to 126.2.192.174126.2.192.17514
12126.2.192.176/28126.2.192.177 to 126.2.192.190126.2.192.19114
13126.2.192.192/28126.2.192.193 to 126.2.192.206126.2.192.20714
14126.2.192.208/28126.2.192.209 to 126.2.192.222126.2.192.22314
15126.2.192.224/28126.2.192.225 to 126.2.192.238126.2.192.23914
16126.2.192.240/28126.2.192.241 to 126.2.192.254126.2.192.25514
17126.2.193.0/28126.2.193.1 to 126.2.193.14126.2.193.1514
18126.2.193.16/28126.2.193.17 to 126.2.193.30126.2.193.3114
19126.2.193.32/28126.2.193.33 to 126.2.193.46126.2.193.4714
20126.2.193.48/28126.2.193.49 to 126.2.193.62126.2.193.6314
21126.2.193.64/28126.2.193.65 to 126.2.193.78126.2.193.7914
22126.2.193.80/28126.2.193.81 to 126.2.193.94126.2.193.9514
23126.2.193.96/28126.2.193.97 to 126.2.193.110126.2.193.11114
24126.2.193.112/28126.2.193.113 to 126.2.193.126126.2.193.12714
25126.2.193.128/28126.2.193.129 to 126.2.193.142126.2.193.14314
26126.2.193.144/28126.2.193.145 to 126.2.193.158126.2.193.15914
27126.2.193.160/28126.2.193.161 to 126.2.193.174126.2.193.17514
28126.2.193.176/28126.2.193.177 to 126.2.193.190126.2.193.19114
29126.2.193.192/28126.2.193.193 to 126.2.193.206126.2.193.20714
30126.2.193.208/28126.2.193.209 to 126.2.193.222126.2.193.22314
31126.2.193.224/28126.2.193.225 to 126.2.193.238126.2.193.23914
32126.2.193.240/28126.2.193.241 to 126.2.193.254126.2.193.25514
33126.2.194.0/28126.2.194.1 to 126.2.194.14126.2.194.1514
34126.2.194.16/28126.2.194.17 to 126.2.194.30126.2.194.3114
35126.2.194.32/28126.2.194.33 to 126.2.194.46126.2.194.4714
36126.2.194.48/28126.2.194.49 to 126.2.194.62126.2.194.6314
37126.2.194.64/28126.2.194.65 to 126.2.194.78126.2.194.7914
38126.2.194.80/28126.2.194.81 to 126.2.194.94126.2.194.9514
39126.2.194.96/28126.2.194.97 to 126.2.194.110126.2.194.11114
40126.2.194.112/28126.2.194.113 to 126.2.194.126126.2.194.12714
41126.2.194.128/28126.2.194.129 to 126.2.194.142126.2.194.14314
42126.2.194.144/28126.2.194.145 to 126.2.194.158126.2.194.15914
43126.2.194.160/28126.2.194.161 to 126.2.194.174126.2.194.17514
44126.2.194.176/28126.2.194.177 to 126.2.194.190126.2.194.19114
45126.2.194.192/28126.2.194.193 to 126.2.194.206126.2.194.20714
46126.2.194.208/28126.2.194.209 to 126.2.194.222126.2.194.22314
47126.2.194.224/28126.2.194.225 to 126.2.194.238126.2.194.23914
48126.2.194.240/28126.2.194.241 to 126.2.194.254126.2.194.25514
49126.2.195.0/28126.2.195.1 to 126.2.195.14126.2.195.1514
50126.2.195.16/28126.2.195.17 to 126.2.195.30126.2.195.3114
51126.2.195.32/28126.2.195.33 to 126.2.195.46126.2.195.4714
52126.2.195.48/28126.2.195.49 to 126.2.195.62126.2.195.6314
53126.2.195.64/28126.2.195.65 to 126.2.195.78126.2.195.7914
54126.2.195.80/28126.2.195.81 to 126.2.195.94126.2.195.9514
55126.2.195.96/28126.2.195.97 to 126.2.195.110126.2.195.11114
56126.2.195.112/28126.2.195.113 to 126.2.195.126126.2.195.12714
57126.2.195.128/28126.2.195.129 to 126.2.195.142126.2.195.14314
58126.2.195.144/28126.2.195.145 to 126.2.195.158126.2.195.15914
59126.2.195.160/28126.2.195.161 to 126.2.195.174126.2.195.17514
60126.2.195.176/28126.2.195.177 to 126.2.195.190126.2.195.19114
61126.2.195.192/28126.2.195.193 to 126.2.195.206126.2.195.20714
62126.2.195.208/28126.2.195.209 to 126.2.195.222126.2.195.22314
63126.2.195.224/28126.2.195.225 to 126.2.195.238126.2.195.23914
64126.2.195.240/28126.2.195.241 to 126.2.195.254126.2.195.25514
65126.2.196.0/28126.2.196.1 to 126.2.196.14126.2.196.1514
66126.2.196.16/28126.2.196.17 to 126.2.196.30126.2.196.3114
67126.2.196.32/28126.2.196.33 to 126.2.196.46126.2.196.4714
68126.2.196.48/28126.2.196.49 to 126.2.196.62126.2.196.6314
69126.2.196.64/28126.2.196.65 to 126.2.196.78126.2.196.7914
70126.2.196.80/28126.2.196.81 to 126.2.196.94126.2.196.9514
71126.2.196.96/28126.2.196.97 to 126.2.196.110126.2.196.11114
72126.2.196.112/28126.2.196.113 to 126.2.196.126126.2.196.12714
73126.2.196.128/28126.2.196.129 to 126.2.196.142126.2.196.14314
74126.2.196.144/28126.2.196.145 to 126.2.196.158126.2.196.15914
75126.2.196.160/28126.2.196.161 to 126.2.196.174126.2.196.17514
76126.2.196.176/28126.2.196.177 to 126.2.196.190126.2.196.19114
77126.2.196.192/28126.2.196.193 to 126.2.196.206126.2.196.20714
78126.2.196.208/28126.2.196.209 to 126.2.196.222126.2.196.22314
79126.2.196.224/28126.2.196.225 to 126.2.196.238126.2.196.23914
80126.2.196.240/28126.2.196.241 to 126.2.196.254126.2.196.25514
81126.2.197.0/28126.2.197.1 to 126.2.197.14126.2.197.1514
82126.2.197.16/28126.2.197.17 to 126.2.197.30126.2.197.3114
83126.2.197.32/28126.2.197.33 to 126.2.197.46126.2.197.4714
84126.2.197.48/28126.2.197.49 to 126.2.197.62126.2.197.6314
85126.2.197.64/28126.2.197.65 to 126.2.197.78126.2.197.7914
86126.2.197.80/28126.2.197.81 to 126.2.197.94126.2.197.9514
87126.2.197.96/28126.2.197.97 to 126.2.197.110126.2.197.11114
88126.2.197.112/28126.2.197.113 to 126.2.197.126126.2.197.12714
89126.2.197.128/28126.2.197.129 to 126.2.197.142126.2.197.14314
90126.2.197.144/28126.2.197.145 to 126.2.197.158126.2.197.15914
91126.2.197.160/28126.2.197.161 to 126.2.197.174126.2.197.17514
92126.2.197.176/28126.2.197.177 to 126.2.197.190126.2.197.19114
93126.2.197.192/28126.2.197.193 to 126.2.197.206126.2.197.20714
94126.2.197.208/28126.2.197.209 to 126.2.197.222126.2.197.22314
95126.2.197.224/28126.2.197.225 to 126.2.197.238126.2.197.23914
96126.2.197.240/28126.2.197.241 to 126.2.197.254126.2.197.25514
97126.2.198.0/28126.2.198.1 to 126.2.198.14126.2.198.1514
98126.2.198.16/28126.2.198.17 to 126.2.198.30126.2.198.3114
99126.2.198.32/28126.2.198.33 to 126.2.198.46126.2.198.4714
100126.2.198.48/28126.2.198.49 to 126.2.198.62126.2.198.6314
101126.2.198.64/28126.2.198.65 to 126.2.198.78126.2.198.7914
102126.2.198.80/28126.2.198.81 to 126.2.198.94126.2.198.9514
103126.2.198.96/28126.2.198.97 to 126.2.198.110126.2.198.11114
104126.2.198.112/28126.2.198.113 to 126.2.198.126126.2.198.12714
105126.2.198.128/28126.2.198.129 to 126.2.198.142126.2.198.14314
106126.2.198.144/28126.2.198.145 to 126.2.198.158126.2.198.15914
107126.2.198.160/28126.2.198.161 to 126.2.198.174126.2.198.17514
108126.2.198.176/28126.2.198.177 to 126.2.198.190126.2.198.19114
109126.2.198.192/28126.2.198.193 to 126.2.198.206126.2.198.20714
110126.2.198.208/28126.2.198.209 to 126.2.198.222126.2.198.22314
111126.2.198.224/28126.2.198.225 to 126.2.198.238126.2.198.23914
112126.2.198.240/28126.2.198.241 to 126.2.198.254126.2.198.25514
113126.2.199.0/28126.2.199.1 to 126.2.199.14126.2.199.1514
114126.2.199.16/28126.2.199.17 to 126.2.199.30126.2.199.3114
115126.2.199.32/28126.2.199.33 to 126.2.199.46126.2.199.4714
116126.2.199.48/28126.2.199.49 to 126.2.199.62126.2.199.6314
117126.2.199.64/28126.2.199.65 to 126.2.199.78126.2.199.7914
118126.2.199.80/28126.2.199.81 to 126.2.199.94126.2.199.9514
119126.2.199.96/28126.2.199.97 to 126.2.199.110126.2.199.11114
120126.2.199.112/28126.2.199.113 to 126.2.199.126126.2.199.12714
121126.2.199.128/28126.2.199.129 to 126.2.199.142126.2.199.14314
122126.2.199.144/28126.2.199.145 to 126.2.199.158126.2.199.15914
123126.2.199.160/28126.2.199.161 to 126.2.199.174126.2.199.17514
124126.2.199.176/28126.2.199.177 to 126.2.199.190126.2.199.19114
125126.2.199.192/28126.2.199.193 to 126.2.199.206126.2.199.20714
126126.2.199.208/28126.2.199.209 to 126.2.199.222126.2.199.22314
127126.2.199.224/28126.2.199.225 to 126.2.199.238126.2.199.23914
128126.2.199.240/28126.2.199.241 to 126.2.199.254126.2.199.25514
129126.2.200.0/28126.2.200.1 to 126.2.200.14126.2.200.1514
130126.2.200.16/28126.2.200.17 to 126.2.200.30126.2.200.3114
131126.2.200.32/28126.2.200.33 to 126.2.200.46126.2.200.4714
132126.2.200.48/28126.2.200.49 to 126.2.200.62126.2.200.6314
133126.2.200.64/28126.2.200.65 to 126.2.200.78126.2.200.7914
134126.2.200.80/28126.2.200.81 to 126.2.200.94126.2.200.9514
135126.2.200.96/28126.2.200.97 to 126.2.200.110126.2.200.11114
136126.2.200.112/28126.2.200.113 to 126.2.200.126126.2.200.12714
137126.2.200.128/28126.2.200.129 to 126.2.200.142126.2.200.14314
138126.2.200.144/28126.2.200.145 to 126.2.200.158126.2.200.15914
139126.2.200.160/28126.2.200.161 to 126.2.200.174126.2.200.17514
140126.2.200.176/28126.2.200.177 to 126.2.200.190126.2.200.19114
141126.2.200.192/28126.2.200.193 to 126.2.200.206126.2.200.20714
142126.2.200.208/28126.2.200.209 to 126.2.200.222126.2.200.22314
143126.2.200.224/28126.2.200.225 to 126.2.200.238126.2.200.23914
144126.2.200.240/28126.2.200.241 to 126.2.200.254126.2.200.25514
145126.2.201.0/28126.2.201.1 to 126.2.201.14126.2.201.1514
146126.2.201.16/28126.2.201.17 to 126.2.201.30126.2.201.3114
147126.2.201.32/28126.2.201.33 to 126.2.201.46126.2.201.4714
148126.2.201.48/28126.2.201.49 to 126.2.201.62126.2.201.6314
149126.2.201.64/28126.2.201.65 to 126.2.201.78126.2.201.7914
150126.2.201.80/28126.2.201.81 to 126.2.201.94126.2.201.9514
151126.2.201.96/28126.2.201.97 to 126.2.201.110126.2.201.11114
152126.2.201.112/28126.2.201.113 to 126.2.201.126126.2.201.12714
153126.2.201.128/28126.2.201.129 to 126.2.201.142126.2.201.14314
154126.2.201.144/28126.2.201.145 to 126.2.201.158126.2.201.15914
155126.2.201.160/28126.2.201.161 to 126.2.201.174126.2.201.17514
156126.2.201.176/28126.2.201.177 to 126.2.201.190126.2.201.19114
157126.2.201.192/28126.2.201.193 to 126.2.201.206126.2.201.20714
158126.2.201.208/28126.2.201.209 to 126.2.201.222126.2.201.22314
159126.2.201.224/28126.2.201.225 to 126.2.201.238126.2.201.23914
160126.2.201.240/28126.2.201.241 to 126.2.201.254126.2.201.25514
161126.2.202.0/28126.2.202.1 to 126.2.202.14126.2.202.1514
162126.2.202.16/28126.2.202.17 to 126.2.202.30126.2.202.3114
163126.2.202.32/28126.2.202.33 to 126.2.202.46126.2.202.4714
164126.2.202.48/28126.2.202.49 to 126.2.202.62126.2.202.6314
165126.2.202.64/28126.2.202.65 to 126.2.202.78126.2.202.7914
166126.2.202.80/28126.2.202.81 to 126.2.202.94126.2.202.9514
167126.2.202.96/28126.2.202.97 to 126.2.202.110126.2.202.11114
168126.2.202.112/28126.2.202.113 to 126.2.202.126126.2.202.12714
169126.2.202.128/28126.2.202.129 to 126.2.202.142126.2.202.14314
170126.2.202.144/28126.2.202.145 to 126.2.202.158126.2.202.15914
171126.2.202.160/28126.2.202.161 to 126.2.202.174126.2.202.17514
172126.2.202.176/28126.2.202.177 to 126.2.202.190126.2.202.19114
173126.2.202.192/28126.2.202.193 to 126.2.202.206126.2.202.20714
174126.2.202.208/28126.2.202.209 to 126.2.202.222126.2.202.22314
175126.2.202.224/28126.2.202.225 to 126.2.202.238126.2.202.23914
176126.2.202.240/28126.2.202.241 to 126.2.202.254126.2.202.25514
177126.2.203.0/28126.2.203.1 to 126.2.203.14126.2.203.1514
178126.2.203.16/28126.2.203.17 to 126.2.203.30126.2.203.3114
179126.2.203.32/28126.2.203.33 to 126.2.203.46126.2.203.4714
180126.2.203.48/28126.2.203.49 to 126.2.203.62126.2.203.6314
181126.2.203.64/28126.2.203.65 to 126.2.203.78126.2.203.7914
182126.2.203.80/28126.2.203.81 to 126.2.203.94126.2.203.9514
183126.2.203.96/28126.2.203.97 to 126.2.203.110126.2.203.11114
184126.2.203.112/28126.2.203.113 to 126.2.203.126126.2.203.12714
185126.2.203.128/28126.2.203.129 to 126.2.203.142126.2.203.14314
186126.2.203.144/28126.2.203.145 to 126.2.203.158126.2.203.15914
187126.2.203.160/28126.2.203.161 to 126.2.203.174126.2.203.17514
188126.2.203.176/28126.2.203.177 to 126.2.203.190126.2.203.19114
189126.2.203.192/28126.2.203.193 to 126.2.203.206126.2.203.20714
190126.2.203.208/28126.2.203.209 to 126.2.203.222126.2.203.22314
191126.2.203.224/28126.2.203.225 to 126.2.203.238126.2.203.23914
192126.2.203.240/28126.2.203.241 to 126.2.203.254126.2.203.25514
193126.2.204.0/28126.2.204.1 to 126.2.204.14126.2.204.1514
194126.2.204.16/28126.2.204.17 to 126.2.204.30126.2.204.3114
195126.2.204.32/28126.2.204.33 to 126.2.204.46126.2.204.4714
196126.2.204.48/28126.2.204.49 to 126.2.204.62126.2.204.6314
197126.2.204.64/28126.2.204.65 to 126.2.204.78126.2.204.7914
198126.2.204.80/28126.2.204.81 to 126.2.204.94126.2.204.9514
199126.2.204.96/28126.2.204.97 to 126.2.204.110126.2.204.11114
200126.2.204.112/28126.2.204.113 to 126.2.204.126126.2.204.12714
201126.2.204.128/28126.2.204.129 to 126.2.204.142126.2.204.14314
202126.2.204.144/28126.2.204.145 to 126.2.204.158126.2.204.15914
203126.2.204.160/28126.2.204.161 to 126.2.204.174126.2.204.17514
204126.2.204.176/28126.2.204.177 to 126.2.204.190126.2.204.19114
205126.2.204.192/28126.2.204.193 to 126.2.204.206126.2.204.20714
206126.2.204.208/28126.2.204.209 to 126.2.204.222126.2.204.22314
207126.2.204.224/28126.2.204.225 to 126.2.204.238126.2.204.23914
208126.2.204.240/28126.2.204.241 to 126.2.204.254126.2.204.25514
209126.2.205.0/28126.2.205.1 to 126.2.205.14126.2.205.1514
210126.2.205.16/28126.2.205.17 to 126.2.205.30126.2.205.3114
211126.2.205.32/28126.2.205.33 to 126.2.205.46126.2.205.4714
212126.2.205.48/28126.2.205.49 to 126.2.205.62126.2.205.6314
213126.2.205.64/28126.2.205.65 to 126.2.205.78126.2.205.7914
214126.2.205.80/28126.2.205.81 to 126.2.205.94126.2.205.9514
215126.2.205.96/28126.2.205.97 to 126.2.205.110126.2.205.11114
216126.2.205.112/28126.2.205.113 to 126.2.205.126126.2.205.12714
217126.2.205.128/28126.2.205.129 to 126.2.205.142126.2.205.14314
218126.2.205.144/28126.2.205.145 to 126.2.205.158126.2.205.15914
219126.2.205.160/28126.2.205.161 to 126.2.205.174126.2.205.17514
220126.2.205.176/28126.2.205.177 to 126.2.205.190126.2.205.19114
221126.2.205.192/28126.2.205.193 to 126.2.205.206126.2.205.20714
222126.2.205.208/28126.2.205.209 to 126.2.205.222126.2.205.22314
223126.2.205.224/28126.2.205.225 to 126.2.205.238126.2.205.23914
224126.2.205.240/28126.2.205.241 to 126.2.205.254126.2.205.25514
225126.2.206.0/28126.2.206.1 to 126.2.206.14126.2.206.1514
226126.2.206.16/28126.2.206.17 to 126.2.206.30126.2.206.3114
227126.2.206.32/28126.2.206.33 to 126.2.206.46126.2.206.4714
228126.2.206.48/28126.2.206.49 to 126.2.206.62126.2.206.6314
229126.2.206.64/28126.2.206.65 to 126.2.206.78126.2.206.7914
230126.2.206.80/28126.2.206.81 to 126.2.206.94126.2.206.9514
231126.2.206.96/28126.2.206.97 to 126.2.206.110126.2.206.11114
232126.2.206.112/28126.2.206.113 to 126.2.206.126126.2.206.12714
233126.2.206.128/28126.2.206.129 to 126.2.206.142126.2.206.14314
234126.2.206.144/28126.2.206.145 to 126.2.206.158126.2.206.15914
235126.2.206.160/28126.2.206.161 to 126.2.206.174126.2.206.17514
236126.2.206.176/28126.2.206.177 to 126.2.206.190126.2.206.19114
237126.2.206.192/28126.2.206.193 to 126.2.206.206126.2.206.20714
238126.2.206.208/28126.2.206.209 to 126.2.206.222126.2.206.22314
239126.2.206.224/28126.2.206.225 to 126.2.206.238126.2.206.23914
240126.2.206.240/28126.2.206.241 to 126.2.206.254126.2.206.25514
241126.2.207.0/28126.2.207.1 to 126.2.207.14126.2.207.1514
242126.2.207.16/28126.2.207.17 to 126.2.207.30126.2.207.3114
243126.2.207.32/28126.2.207.33 to 126.2.207.46126.2.207.4714
244126.2.207.48/28126.2.207.49 to 126.2.207.62126.2.207.6314
245126.2.207.64/28126.2.207.65 to 126.2.207.78126.2.207.7914
246126.2.207.80/28126.2.207.81 to 126.2.207.94126.2.207.9514
247126.2.207.96/28126.2.207.97 to 126.2.207.110126.2.207.11114
248126.2.207.112/28126.2.207.113 to 126.2.207.126126.2.207.12714
249126.2.207.128/28126.2.207.129 to 126.2.207.142126.2.207.14314
250126.2.207.144/28126.2.207.145 to 126.2.207.158126.2.207.15914
251126.2.207.160/28126.2.207.161 to 126.2.207.174126.2.207.17514
252126.2.207.176/28126.2.207.177 to 126.2.207.190126.2.207.19114
253126.2.207.192/28126.2.207.193 to 126.2.207.206126.2.207.20714
254126.2.207.208/28126.2.207.209 to 126.2.207.222126.2.207.22314
255126.2.207.224/28126.2.207.225 to 126.2.207.238126.2.207.23914
256126.2.207.240/28126.2.207.241 to 126.2.207.254126.2.207.25514

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.