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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.

Network176.0.0.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
176.0.0.0
Broadcast address
176.0.31.255
First usable
176.0.0.1
Last usable
176.0.31.254
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
B (default /16)
As numbers
Hex B0000000 · Integer 2952790016 to 2952798207
Reverse DNS zones
0.0.176.in-addr.arpa
1.0.176.in-addr.arpa
2.0.176.in-addr.arpa
3.0.176.in-addr.arpa
4.0.176.in-addr.arpa
5.0.176.in-addr.arpa
6.0.176.in-addr.arpa
7.0.176.in-addr.arpa
8.0.176.in-addr.arpa
9.0.176.in-addr.arpa
10.0.176.in-addr.arpa
11.0.176.in-addr.arpa
12.0.176.in-addr.arpa
13.0.176.in-addr.arpa
14.0.176.in-addr.arpa
15.0.176.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
Address10110000.00000000.00000000.00000000176.0.0.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network10110000.00000000.00000000.00000000176.0.0.0
Broadcast10110000.00000000.00011111.11111111176.0.31.255
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)

176.0.0.0/19 makes 512 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1176.0.0.0/28176.0.0.1 to 176.0.0.14176.0.0.1514
2176.0.0.16/28176.0.0.17 to 176.0.0.30176.0.0.3114
3176.0.0.32/28176.0.0.33 to 176.0.0.46176.0.0.4714
4176.0.0.48/28176.0.0.49 to 176.0.0.62176.0.0.6314
5176.0.0.64/28176.0.0.65 to 176.0.0.78176.0.0.7914
6176.0.0.80/28176.0.0.81 to 176.0.0.94176.0.0.9514
7176.0.0.96/28176.0.0.97 to 176.0.0.110176.0.0.11114
8176.0.0.112/28176.0.0.113 to 176.0.0.126176.0.0.12714
9176.0.0.128/28176.0.0.129 to 176.0.0.142176.0.0.14314
10176.0.0.144/28176.0.0.145 to 176.0.0.158176.0.0.15914
11176.0.0.160/28176.0.0.161 to 176.0.0.174176.0.0.17514
12176.0.0.176/28176.0.0.177 to 176.0.0.190176.0.0.19114
13176.0.0.192/28176.0.0.193 to 176.0.0.206176.0.0.20714
14176.0.0.208/28176.0.0.209 to 176.0.0.222176.0.0.22314
15176.0.0.224/28176.0.0.225 to 176.0.0.238176.0.0.23914
16176.0.0.240/28176.0.0.241 to 176.0.0.254176.0.0.25514
17176.0.1.0/28176.0.1.1 to 176.0.1.14176.0.1.1514
18176.0.1.16/28176.0.1.17 to 176.0.1.30176.0.1.3114
19176.0.1.32/28176.0.1.33 to 176.0.1.46176.0.1.4714
20176.0.1.48/28176.0.1.49 to 176.0.1.62176.0.1.6314
21176.0.1.64/28176.0.1.65 to 176.0.1.78176.0.1.7914
22176.0.1.80/28176.0.1.81 to 176.0.1.94176.0.1.9514
23176.0.1.96/28176.0.1.97 to 176.0.1.110176.0.1.11114
24176.0.1.112/28176.0.1.113 to 176.0.1.126176.0.1.12714
25176.0.1.128/28176.0.1.129 to 176.0.1.142176.0.1.14314
26176.0.1.144/28176.0.1.145 to 176.0.1.158176.0.1.15914
27176.0.1.160/28176.0.1.161 to 176.0.1.174176.0.1.17514
28176.0.1.176/28176.0.1.177 to 176.0.1.190176.0.1.19114
29176.0.1.192/28176.0.1.193 to 176.0.1.206176.0.1.20714
30176.0.1.208/28176.0.1.209 to 176.0.1.222176.0.1.22314
31176.0.1.224/28176.0.1.225 to 176.0.1.238176.0.1.23914
32176.0.1.240/28176.0.1.241 to 176.0.1.254176.0.1.25514
33176.0.2.0/28176.0.2.1 to 176.0.2.14176.0.2.1514
34176.0.2.16/28176.0.2.17 to 176.0.2.30176.0.2.3114
35176.0.2.32/28176.0.2.33 to 176.0.2.46176.0.2.4714
36176.0.2.48/28176.0.2.49 to 176.0.2.62176.0.2.6314
37176.0.2.64/28176.0.2.65 to 176.0.2.78176.0.2.7914
38176.0.2.80/28176.0.2.81 to 176.0.2.94176.0.2.9514
39176.0.2.96/28176.0.2.97 to 176.0.2.110176.0.2.11114
40176.0.2.112/28176.0.2.113 to 176.0.2.126176.0.2.12714
41176.0.2.128/28176.0.2.129 to 176.0.2.142176.0.2.14314
42176.0.2.144/28176.0.2.145 to 176.0.2.158176.0.2.15914
43176.0.2.160/28176.0.2.161 to 176.0.2.174176.0.2.17514
44176.0.2.176/28176.0.2.177 to 176.0.2.190176.0.2.19114
45176.0.2.192/28176.0.2.193 to 176.0.2.206176.0.2.20714
46176.0.2.208/28176.0.2.209 to 176.0.2.222176.0.2.22314
47176.0.2.224/28176.0.2.225 to 176.0.2.238176.0.2.23914
48176.0.2.240/28176.0.2.241 to 176.0.2.254176.0.2.25514
49176.0.3.0/28176.0.3.1 to 176.0.3.14176.0.3.1514
50176.0.3.16/28176.0.3.17 to 176.0.3.30176.0.3.3114
51176.0.3.32/28176.0.3.33 to 176.0.3.46176.0.3.4714
52176.0.3.48/28176.0.3.49 to 176.0.3.62176.0.3.6314
53176.0.3.64/28176.0.3.65 to 176.0.3.78176.0.3.7914
54176.0.3.80/28176.0.3.81 to 176.0.3.94176.0.3.9514
55176.0.3.96/28176.0.3.97 to 176.0.3.110176.0.3.11114
56176.0.3.112/28176.0.3.113 to 176.0.3.126176.0.3.12714
57176.0.3.128/28176.0.3.129 to 176.0.3.142176.0.3.14314
58176.0.3.144/28176.0.3.145 to 176.0.3.158176.0.3.15914
59176.0.3.160/28176.0.3.161 to 176.0.3.174176.0.3.17514
60176.0.3.176/28176.0.3.177 to 176.0.3.190176.0.3.19114
61176.0.3.192/28176.0.3.193 to 176.0.3.206176.0.3.20714
62176.0.3.208/28176.0.3.209 to 176.0.3.222176.0.3.22314
63176.0.3.224/28176.0.3.225 to 176.0.3.238176.0.3.23914
64176.0.3.240/28176.0.3.241 to 176.0.3.254176.0.3.25514
65176.0.4.0/28176.0.4.1 to 176.0.4.14176.0.4.1514
66176.0.4.16/28176.0.4.17 to 176.0.4.30176.0.4.3114
67176.0.4.32/28176.0.4.33 to 176.0.4.46176.0.4.4714
68176.0.4.48/28176.0.4.49 to 176.0.4.62176.0.4.6314
69176.0.4.64/28176.0.4.65 to 176.0.4.78176.0.4.7914
70176.0.4.80/28176.0.4.81 to 176.0.4.94176.0.4.9514
71176.0.4.96/28176.0.4.97 to 176.0.4.110176.0.4.11114
72176.0.4.112/28176.0.4.113 to 176.0.4.126176.0.4.12714
73176.0.4.128/28176.0.4.129 to 176.0.4.142176.0.4.14314
74176.0.4.144/28176.0.4.145 to 176.0.4.158176.0.4.15914
75176.0.4.160/28176.0.4.161 to 176.0.4.174176.0.4.17514
76176.0.4.176/28176.0.4.177 to 176.0.4.190176.0.4.19114
77176.0.4.192/28176.0.4.193 to 176.0.4.206176.0.4.20714
78176.0.4.208/28176.0.4.209 to 176.0.4.222176.0.4.22314
79176.0.4.224/28176.0.4.225 to 176.0.4.238176.0.4.23914
80176.0.4.240/28176.0.4.241 to 176.0.4.254176.0.4.25514
81176.0.5.0/28176.0.5.1 to 176.0.5.14176.0.5.1514
82176.0.5.16/28176.0.5.17 to 176.0.5.30176.0.5.3114
83176.0.5.32/28176.0.5.33 to 176.0.5.46176.0.5.4714
84176.0.5.48/28176.0.5.49 to 176.0.5.62176.0.5.6314
85176.0.5.64/28176.0.5.65 to 176.0.5.78176.0.5.7914
86176.0.5.80/28176.0.5.81 to 176.0.5.94176.0.5.9514
87176.0.5.96/28176.0.5.97 to 176.0.5.110176.0.5.11114
88176.0.5.112/28176.0.5.113 to 176.0.5.126176.0.5.12714
89176.0.5.128/28176.0.5.129 to 176.0.5.142176.0.5.14314
90176.0.5.144/28176.0.5.145 to 176.0.5.158176.0.5.15914
91176.0.5.160/28176.0.5.161 to 176.0.5.174176.0.5.17514
92176.0.5.176/28176.0.5.177 to 176.0.5.190176.0.5.19114
93176.0.5.192/28176.0.5.193 to 176.0.5.206176.0.5.20714
94176.0.5.208/28176.0.5.209 to 176.0.5.222176.0.5.22314
95176.0.5.224/28176.0.5.225 to 176.0.5.238176.0.5.23914
96176.0.5.240/28176.0.5.241 to 176.0.5.254176.0.5.25514
97176.0.6.0/28176.0.6.1 to 176.0.6.14176.0.6.1514
98176.0.6.16/28176.0.6.17 to 176.0.6.30176.0.6.3114
99176.0.6.32/28176.0.6.33 to 176.0.6.46176.0.6.4714
100176.0.6.48/28176.0.6.49 to 176.0.6.62176.0.6.6314
101176.0.6.64/28176.0.6.65 to 176.0.6.78176.0.6.7914
102176.0.6.80/28176.0.6.81 to 176.0.6.94176.0.6.9514
103176.0.6.96/28176.0.6.97 to 176.0.6.110176.0.6.11114
104176.0.6.112/28176.0.6.113 to 176.0.6.126176.0.6.12714
105176.0.6.128/28176.0.6.129 to 176.0.6.142176.0.6.14314
106176.0.6.144/28176.0.6.145 to 176.0.6.158176.0.6.15914
107176.0.6.160/28176.0.6.161 to 176.0.6.174176.0.6.17514
108176.0.6.176/28176.0.6.177 to 176.0.6.190176.0.6.19114
109176.0.6.192/28176.0.6.193 to 176.0.6.206176.0.6.20714
110176.0.6.208/28176.0.6.209 to 176.0.6.222176.0.6.22314
111176.0.6.224/28176.0.6.225 to 176.0.6.238176.0.6.23914
112176.0.6.240/28176.0.6.241 to 176.0.6.254176.0.6.25514
113176.0.7.0/28176.0.7.1 to 176.0.7.14176.0.7.1514
114176.0.7.16/28176.0.7.17 to 176.0.7.30176.0.7.3114
115176.0.7.32/28176.0.7.33 to 176.0.7.46176.0.7.4714
116176.0.7.48/28176.0.7.49 to 176.0.7.62176.0.7.6314
117176.0.7.64/28176.0.7.65 to 176.0.7.78176.0.7.7914
118176.0.7.80/28176.0.7.81 to 176.0.7.94176.0.7.9514
119176.0.7.96/28176.0.7.97 to 176.0.7.110176.0.7.11114
120176.0.7.112/28176.0.7.113 to 176.0.7.126176.0.7.12714
121176.0.7.128/28176.0.7.129 to 176.0.7.142176.0.7.14314
122176.0.7.144/28176.0.7.145 to 176.0.7.158176.0.7.15914
123176.0.7.160/28176.0.7.161 to 176.0.7.174176.0.7.17514
124176.0.7.176/28176.0.7.177 to 176.0.7.190176.0.7.19114
125176.0.7.192/28176.0.7.193 to 176.0.7.206176.0.7.20714
126176.0.7.208/28176.0.7.209 to 176.0.7.222176.0.7.22314
127176.0.7.224/28176.0.7.225 to 176.0.7.238176.0.7.23914
128176.0.7.240/28176.0.7.241 to 176.0.7.254176.0.7.25514
129176.0.8.0/28176.0.8.1 to 176.0.8.14176.0.8.1514
130176.0.8.16/28176.0.8.17 to 176.0.8.30176.0.8.3114
131176.0.8.32/28176.0.8.33 to 176.0.8.46176.0.8.4714
132176.0.8.48/28176.0.8.49 to 176.0.8.62176.0.8.6314
133176.0.8.64/28176.0.8.65 to 176.0.8.78176.0.8.7914
134176.0.8.80/28176.0.8.81 to 176.0.8.94176.0.8.9514
135176.0.8.96/28176.0.8.97 to 176.0.8.110176.0.8.11114
136176.0.8.112/28176.0.8.113 to 176.0.8.126176.0.8.12714
137176.0.8.128/28176.0.8.129 to 176.0.8.142176.0.8.14314
138176.0.8.144/28176.0.8.145 to 176.0.8.158176.0.8.15914
139176.0.8.160/28176.0.8.161 to 176.0.8.174176.0.8.17514
140176.0.8.176/28176.0.8.177 to 176.0.8.190176.0.8.19114
141176.0.8.192/28176.0.8.193 to 176.0.8.206176.0.8.20714
142176.0.8.208/28176.0.8.209 to 176.0.8.222176.0.8.22314
143176.0.8.224/28176.0.8.225 to 176.0.8.238176.0.8.23914
144176.0.8.240/28176.0.8.241 to 176.0.8.254176.0.8.25514
145176.0.9.0/28176.0.9.1 to 176.0.9.14176.0.9.1514
146176.0.9.16/28176.0.9.17 to 176.0.9.30176.0.9.3114
147176.0.9.32/28176.0.9.33 to 176.0.9.46176.0.9.4714
148176.0.9.48/28176.0.9.49 to 176.0.9.62176.0.9.6314
149176.0.9.64/28176.0.9.65 to 176.0.9.78176.0.9.7914
150176.0.9.80/28176.0.9.81 to 176.0.9.94176.0.9.9514
151176.0.9.96/28176.0.9.97 to 176.0.9.110176.0.9.11114
152176.0.9.112/28176.0.9.113 to 176.0.9.126176.0.9.12714
153176.0.9.128/28176.0.9.129 to 176.0.9.142176.0.9.14314
154176.0.9.144/28176.0.9.145 to 176.0.9.158176.0.9.15914
155176.0.9.160/28176.0.9.161 to 176.0.9.174176.0.9.17514
156176.0.9.176/28176.0.9.177 to 176.0.9.190176.0.9.19114
157176.0.9.192/28176.0.9.193 to 176.0.9.206176.0.9.20714
158176.0.9.208/28176.0.9.209 to 176.0.9.222176.0.9.22314
159176.0.9.224/28176.0.9.225 to 176.0.9.238176.0.9.23914
160176.0.9.240/28176.0.9.241 to 176.0.9.254176.0.9.25514
161176.0.10.0/28176.0.10.1 to 176.0.10.14176.0.10.1514
162176.0.10.16/28176.0.10.17 to 176.0.10.30176.0.10.3114
163176.0.10.32/28176.0.10.33 to 176.0.10.46176.0.10.4714
164176.0.10.48/28176.0.10.49 to 176.0.10.62176.0.10.6314
165176.0.10.64/28176.0.10.65 to 176.0.10.78176.0.10.7914
166176.0.10.80/28176.0.10.81 to 176.0.10.94176.0.10.9514
167176.0.10.96/28176.0.10.97 to 176.0.10.110176.0.10.11114
168176.0.10.112/28176.0.10.113 to 176.0.10.126176.0.10.12714
169176.0.10.128/28176.0.10.129 to 176.0.10.142176.0.10.14314
170176.0.10.144/28176.0.10.145 to 176.0.10.158176.0.10.15914
171176.0.10.160/28176.0.10.161 to 176.0.10.174176.0.10.17514
172176.0.10.176/28176.0.10.177 to 176.0.10.190176.0.10.19114
173176.0.10.192/28176.0.10.193 to 176.0.10.206176.0.10.20714
174176.0.10.208/28176.0.10.209 to 176.0.10.222176.0.10.22314
175176.0.10.224/28176.0.10.225 to 176.0.10.238176.0.10.23914
176176.0.10.240/28176.0.10.241 to 176.0.10.254176.0.10.25514
177176.0.11.0/28176.0.11.1 to 176.0.11.14176.0.11.1514
178176.0.11.16/28176.0.11.17 to 176.0.11.30176.0.11.3114
179176.0.11.32/28176.0.11.33 to 176.0.11.46176.0.11.4714
180176.0.11.48/28176.0.11.49 to 176.0.11.62176.0.11.6314
181176.0.11.64/28176.0.11.65 to 176.0.11.78176.0.11.7914
182176.0.11.80/28176.0.11.81 to 176.0.11.94176.0.11.9514
183176.0.11.96/28176.0.11.97 to 176.0.11.110176.0.11.11114
184176.0.11.112/28176.0.11.113 to 176.0.11.126176.0.11.12714
185176.0.11.128/28176.0.11.129 to 176.0.11.142176.0.11.14314
186176.0.11.144/28176.0.11.145 to 176.0.11.158176.0.11.15914
187176.0.11.160/28176.0.11.161 to 176.0.11.174176.0.11.17514
188176.0.11.176/28176.0.11.177 to 176.0.11.190176.0.11.19114
189176.0.11.192/28176.0.11.193 to 176.0.11.206176.0.11.20714
190176.0.11.208/28176.0.11.209 to 176.0.11.222176.0.11.22314
191176.0.11.224/28176.0.11.225 to 176.0.11.238176.0.11.23914
192176.0.11.240/28176.0.11.241 to 176.0.11.254176.0.11.25514
193176.0.12.0/28176.0.12.1 to 176.0.12.14176.0.12.1514
194176.0.12.16/28176.0.12.17 to 176.0.12.30176.0.12.3114
195176.0.12.32/28176.0.12.33 to 176.0.12.46176.0.12.4714
196176.0.12.48/28176.0.12.49 to 176.0.12.62176.0.12.6314
197176.0.12.64/28176.0.12.65 to 176.0.12.78176.0.12.7914
198176.0.12.80/28176.0.12.81 to 176.0.12.94176.0.12.9514
199176.0.12.96/28176.0.12.97 to 176.0.12.110176.0.12.11114
200176.0.12.112/28176.0.12.113 to 176.0.12.126176.0.12.12714
201176.0.12.128/28176.0.12.129 to 176.0.12.142176.0.12.14314
202176.0.12.144/28176.0.12.145 to 176.0.12.158176.0.12.15914
203176.0.12.160/28176.0.12.161 to 176.0.12.174176.0.12.17514
204176.0.12.176/28176.0.12.177 to 176.0.12.190176.0.12.19114
205176.0.12.192/28176.0.12.193 to 176.0.12.206176.0.12.20714
206176.0.12.208/28176.0.12.209 to 176.0.12.222176.0.12.22314
207176.0.12.224/28176.0.12.225 to 176.0.12.238176.0.12.23914
208176.0.12.240/28176.0.12.241 to 176.0.12.254176.0.12.25514
209176.0.13.0/28176.0.13.1 to 176.0.13.14176.0.13.1514
210176.0.13.16/28176.0.13.17 to 176.0.13.30176.0.13.3114
211176.0.13.32/28176.0.13.33 to 176.0.13.46176.0.13.4714
212176.0.13.48/28176.0.13.49 to 176.0.13.62176.0.13.6314
213176.0.13.64/28176.0.13.65 to 176.0.13.78176.0.13.7914
214176.0.13.80/28176.0.13.81 to 176.0.13.94176.0.13.9514
215176.0.13.96/28176.0.13.97 to 176.0.13.110176.0.13.11114
216176.0.13.112/28176.0.13.113 to 176.0.13.126176.0.13.12714
217176.0.13.128/28176.0.13.129 to 176.0.13.142176.0.13.14314
218176.0.13.144/28176.0.13.145 to 176.0.13.158176.0.13.15914
219176.0.13.160/28176.0.13.161 to 176.0.13.174176.0.13.17514
220176.0.13.176/28176.0.13.177 to 176.0.13.190176.0.13.19114
221176.0.13.192/28176.0.13.193 to 176.0.13.206176.0.13.20714
222176.0.13.208/28176.0.13.209 to 176.0.13.222176.0.13.22314
223176.0.13.224/28176.0.13.225 to 176.0.13.238176.0.13.23914
224176.0.13.240/28176.0.13.241 to 176.0.13.254176.0.13.25514
225176.0.14.0/28176.0.14.1 to 176.0.14.14176.0.14.1514
226176.0.14.16/28176.0.14.17 to 176.0.14.30176.0.14.3114
227176.0.14.32/28176.0.14.33 to 176.0.14.46176.0.14.4714
228176.0.14.48/28176.0.14.49 to 176.0.14.62176.0.14.6314
229176.0.14.64/28176.0.14.65 to 176.0.14.78176.0.14.7914
230176.0.14.80/28176.0.14.81 to 176.0.14.94176.0.14.9514
231176.0.14.96/28176.0.14.97 to 176.0.14.110176.0.14.11114
232176.0.14.112/28176.0.14.113 to 176.0.14.126176.0.14.12714
233176.0.14.128/28176.0.14.129 to 176.0.14.142176.0.14.14314
234176.0.14.144/28176.0.14.145 to 176.0.14.158176.0.14.15914
235176.0.14.160/28176.0.14.161 to 176.0.14.174176.0.14.17514
236176.0.14.176/28176.0.14.177 to 176.0.14.190176.0.14.19114
237176.0.14.192/28176.0.14.193 to 176.0.14.206176.0.14.20714
238176.0.14.208/28176.0.14.209 to 176.0.14.222176.0.14.22314
239176.0.14.224/28176.0.14.225 to 176.0.14.238176.0.14.23914
240176.0.14.240/28176.0.14.241 to 176.0.14.254176.0.14.25514
241176.0.15.0/28176.0.15.1 to 176.0.15.14176.0.15.1514
242176.0.15.16/28176.0.15.17 to 176.0.15.30176.0.15.3114
243176.0.15.32/28176.0.15.33 to 176.0.15.46176.0.15.4714
244176.0.15.48/28176.0.15.49 to 176.0.15.62176.0.15.6314
245176.0.15.64/28176.0.15.65 to 176.0.15.78176.0.15.7914
246176.0.15.80/28176.0.15.81 to 176.0.15.94176.0.15.9514
247176.0.15.96/28176.0.15.97 to 176.0.15.110176.0.15.11114
248176.0.15.112/28176.0.15.113 to 176.0.15.126176.0.15.12714
249176.0.15.128/28176.0.15.129 to 176.0.15.142176.0.15.14314
250176.0.15.144/28176.0.15.145 to 176.0.15.158176.0.15.15914
251176.0.15.160/28176.0.15.161 to 176.0.15.174176.0.15.17514
252176.0.15.176/28176.0.15.177 to 176.0.15.190176.0.15.19114
253176.0.15.192/28176.0.15.193 to 176.0.15.206176.0.15.20714
254176.0.15.208/28176.0.15.209 to 176.0.15.222176.0.15.22314
255176.0.15.224/28176.0.15.225 to 176.0.15.238176.0.15.23914
256176.0.15.240/28176.0.15.241 to 176.0.15.254176.0.15.25514

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.