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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.

Network114.7.64.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
114.7.64.0
Broadcast address
114.7.95.255
First usable
114.7.64.1
Last usable
114.7.95.254
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
Public public
Old class
A (default /8)
As numbers
Hex 72074000 · Integer 1913077760 to 1913085951
Reverse DNS zones
64.7.114.in-addr.arpa
65.7.114.in-addr.arpa
66.7.114.in-addr.arpa
67.7.114.in-addr.arpa
68.7.114.in-addr.arpa
69.7.114.in-addr.arpa
70.7.114.in-addr.arpa
71.7.114.in-addr.arpa
72.7.114.in-addr.arpa
73.7.114.in-addr.arpa
74.7.114.in-addr.arpa
75.7.114.in-addr.arpa
76.7.114.in-addr.arpa
77.7.114.in-addr.arpa
78.7.114.in-addr.arpa
79.7.114.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
Address01110010.00000111.01000000.00000000114.7.64.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network01110010.00000111.01000000.00000000114.7.64.0
Broadcast01110010.00000111.01011111.11111111114.7.95.255
Split into smaller subnets/29
/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)

114.7.64.0/19 makes 1,024 subnets of /29; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1114.7.64.0/29114.7.64.1 to 114.7.64.6114.7.64.76
2114.7.64.8/29114.7.64.9 to 114.7.64.14114.7.64.156
3114.7.64.16/29114.7.64.17 to 114.7.64.22114.7.64.236
4114.7.64.24/29114.7.64.25 to 114.7.64.30114.7.64.316
5114.7.64.32/29114.7.64.33 to 114.7.64.38114.7.64.396
6114.7.64.40/29114.7.64.41 to 114.7.64.46114.7.64.476
7114.7.64.48/29114.7.64.49 to 114.7.64.54114.7.64.556
8114.7.64.56/29114.7.64.57 to 114.7.64.62114.7.64.636
9114.7.64.64/29114.7.64.65 to 114.7.64.70114.7.64.716
10114.7.64.72/29114.7.64.73 to 114.7.64.78114.7.64.796
11114.7.64.80/29114.7.64.81 to 114.7.64.86114.7.64.876
12114.7.64.88/29114.7.64.89 to 114.7.64.94114.7.64.956
13114.7.64.96/29114.7.64.97 to 114.7.64.102114.7.64.1036
14114.7.64.104/29114.7.64.105 to 114.7.64.110114.7.64.1116
15114.7.64.112/29114.7.64.113 to 114.7.64.118114.7.64.1196
16114.7.64.120/29114.7.64.121 to 114.7.64.126114.7.64.1276
17114.7.64.128/29114.7.64.129 to 114.7.64.134114.7.64.1356
18114.7.64.136/29114.7.64.137 to 114.7.64.142114.7.64.1436
19114.7.64.144/29114.7.64.145 to 114.7.64.150114.7.64.1516
20114.7.64.152/29114.7.64.153 to 114.7.64.158114.7.64.1596
21114.7.64.160/29114.7.64.161 to 114.7.64.166114.7.64.1676
22114.7.64.168/29114.7.64.169 to 114.7.64.174114.7.64.1756
23114.7.64.176/29114.7.64.177 to 114.7.64.182114.7.64.1836
24114.7.64.184/29114.7.64.185 to 114.7.64.190114.7.64.1916
25114.7.64.192/29114.7.64.193 to 114.7.64.198114.7.64.1996
26114.7.64.200/29114.7.64.201 to 114.7.64.206114.7.64.2076
27114.7.64.208/29114.7.64.209 to 114.7.64.214114.7.64.2156
28114.7.64.216/29114.7.64.217 to 114.7.64.222114.7.64.2236
29114.7.64.224/29114.7.64.225 to 114.7.64.230114.7.64.2316
30114.7.64.232/29114.7.64.233 to 114.7.64.238114.7.64.2396
31114.7.64.240/29114.7.64.241 to 114.7.64.246114.7.64.2476
32114.7.64.248/29114.7.64.249 to 114.7.64.254114.7.64.2556
33114.7.65.0/29114.7.65.1 to 114.7.65.6114.7.65.76
34114.7.65.8/29114.7.65.9 to 114.7.65.14114.7.65.156
35114.7.65.16/29114.7.65.17 to 114.7.65.22114.7.65.236
36114.7.65.24/29114.7.65.25 to 114.7.65.30114.7.65.316
37114.7.65.32/29114.7.65.33 to 114.7.65.38114.7.65.396
38114.7.65.40/29114.7.65.41 to 114.7.65.46114.7.65.476
39114.7.65.48/29114.7.65.49 to 114.7.65.54114.7.65.556
40114.7.65.56/29114.7.65.57 to 114.7.65.62114.7.65.636
41114.7.65.64/29114.7.65.65 to 114.7.65.70114.7.65.716
42114.7.65.72/29114.7.65.73 to 114.7.65.78114.7.65.796
43114.7.65.80/29114.7.65.81 to 114.7.65.86114.7.65.876
44114.7.65.88/29114.7.65.89 to 114.7.65.94114.7.65.956
45114.7.65.96/29114.7.65.97 to 114.7.65.102114.7.65.1036
46114.7.65.104/29114.7.65.105 to 114.7.65.110114.7.65.1116
47114.7.65.112/29114.7.65.113 to 114.7.65.118114.7.65.1196
48114.7.65.120/29114.7.65.121 to 114.7.65.126114.7.65.1276
49114.7.65.128/29114.7.65.129 to 114.7.65.134114.7.65.1356
50114.7.65.136/29114.7.65.137 to 114.7.65.142114.7.65.1436
51114.7.65.144/29114.7.65.145 to 114.7.65.150114.7.65.1516
52114.7.65.152/29114.7.65.153 to 114.7.65.158114.7.65.1596
53114.7.65.160/29114.7.65.161 to 114.7.65.166114.7.65.1676
54114.7.65.168/29114.7.65.169 to 114.7.65.174114.7.65.1756
55114.7.65.176/29114.7.65.177 to 114.7.65.182114.7.65.1836
56114.7.65.184/29114.7.65.185 to 114.7.65.190114.7.65.1916
57114.7.65.192/29114.7.65.193 to 114.7.65.198114.7.65.1996
58114.7.65.200/29114.7.65.201 to 114.7.65.206114.7.65.2076
59114.7.65.208/29114.7.65.209 to 114.7.65.214114.7.65.2156
60114.7.65.216/29114.7.65.217 to 114.7.65.222114.7.65.2236
61114.7.65.224/29114.7.65.225 to 114.7.65.230114.7.65.2316
62114.7.65.232/29114.7.65.233 to 114.7.65.238114.7.65.2396
63114.7.65.240/29114.7.65.241 to 114.7.65.246114.7.65.2476
64114.7.65.248/29114.7.65.249 to 114.7.65.254114.7.65.2556
65114.7.66.0/29114.7.66.1 to 114.7.66.6114.7.66.76
66114.7.66.8/29114.7.66.9 to 114.7.66.14114.7.66.156
67114.7.66.16/29114.7.66.17 to 114.7.66.22114.7.66.236
68114.7.66.24/29114.7.66.25 to 114.7.66.30114.7.66.316
69114.7.66.32/29114.7.66.33 to 114.7.66.38114.7.66.396
70114.7.66.40/29114.7.66.41 to 114.7.66.46114.7.66.476
71114.7.66.48/29114.7.66.49 to 114.7.66.54114.7.66.556
72114.7.66.56/29114.7.66.57 to 114.7.66.62114.7.66.636
73114.7.66.64/29114.7.66.65 to 114.7.66.70114.7.66.716
74114.7.66.72/29114.7.66.73 to 114.7.66.78114.7.66.796
75114.7.66.80/29114.7.66.81 to 114.7.66.86114.7.66.876
76114.7.66.88/29114.7.66.89 to 114.7.66.94114.7.66.956
77114.7.66.96/29114.7.66.97 to 114.7.66.102114.7.66.1036
78114.7.66.104/29114.7.66.105 to 114.7.66.110114.7.66.1116
79114.7.66.112/29114.7.66.113 to 114.7.66.118114.7.66.1196
80114.7.66.120/29114.7.66.121 to 114.7.66.126114.7.66.1276
81114.7.66.128/29114.7.66.129 to 114.7.66.134114.7.66.1356
82114.7.66.136/29114.7.66.137 to 114.7.66.142114.7.66.1436
83114.7.66.144/29114.7.66.145 to 114.7.66.150114.7.66.1516
84114.7.66.152/29114.7.66.153 to 114.7.66.158114.7.66.1596
85114.7.66.160/29114.7.66.161 to 114.7.66.166114.7.66.1676
86114.7.66.168/29114.7.66.169 to 114.7.66.174114.7.66.1756
87114.7.66.176/29114.7.66.177 to 114.7.66.182114.7.66.1836
88114.7.66.184/29114.7.66.185 to 114.7.66.190114.7.66.1916
89114.7.66.192/29114.7.66.193 to 114.7.66.198114.7.66.1996
90114.7.66.200/29114.7.66.201 to 114.7.66.206114.7.66.2076
91114.7.66.208/29114.7.66.209 to 114.7.66.214114.7.66.2156
92114.7.66.216/29114.7.66.217 to 114.7.66.222114.7.66.2236
93114.7.66.224/29114.7.66.225 to 114.7.66.230114.7.66.2316
94114.7.66.232/29114.7.66.233 to 114.7.66.238114.7.66.2396
95114.7.66.240/29114.7.66.241 to 114.7.66.246114.7.66.2476
96114.7.66.248/29114.7.66.249 to 114.7.66.254114.7.66.2556
97114.7.67.0/29114.7.67.1 to 114.7.67.6114.7.67.76
98114.7.67.8/29114.7.67.9 to 114.7.67.14114.7.67.156
99114.7.67.16/29114.7.67.17 to 114.7.67.22114.7.67.236
100114.7.67.24/29114.7.67.25 to 114.7.67.30114.7.67.316
101114.7.67.32/29114.7.67.33 to 114.7.67.38114.7.67.396
102114.7.67.40/29114.7.67.41 to 114.7.67.46114.7.67.476
103114.7.67.48/29114.7.67.49 to 114.7.67.54114.7.67.556
104114.7.67.56/29114.7.67.57 to 114.7.67.62114.7.67.636
105114.7.67.64/29114.7.67.65 to 114.7.67.70114.7.67.716
106114.7.67.72/29114.7.67.73 to 114.7.67.78114.7.67.796
107114.7.67.80/29114.7.67.81 to 114.7.67.86114.7.67.876
108114.7.67.88/29114.7.67.89 to 114.7.67.94114.7.67.956
109114.7.67.96/29114.7.67.97 to 114.7.67.102114.7.67.1036
110114.7.67.104/29114.7.67.105 to 114.7.67.110114.7.67.1116
111114.7.67.112/29114.7.67.113 to 114.7.67.118114.7.67.1196
112114.7.67.120/29114.7.67.121 to 114.7.67.126114.7.67.1276
113114.7.67.128/29114.7.67.129 to 114.7.67.134114.7.67.1356
114114.7.67.136/29114.7.67.137 to 114.7.67.142114.7.67.1436
115114.7.67.144/29114.7.67.145 to 114.7.67.150114.7.67.1516
116114.7.67.152/29114.7.67.153 to 114.7.67.158114.7.67.1596
117114.7.67.160/29114.7.67.161 to 114.7.67.166114.7.67.1676
118114.7.67.168/29114.7.67.169 to 114.7.67.174114.7.67.1756
119114.7.67.176/29114.7.67.177 to 114.7.67.182114.7.67.1836
120114.7.67.184/29114.7.67.185 to 114.7.67.190114.7.67.1916
121114.7.67.192/29114.7.67.193 to 114.7.67.198114.7.67.1996
122114.7.67.200/29114.7.67.201 to 114.7.67.206114.7.67.2076
123114.7.67.208/29114.7.67.209 to 114.7.67.214114.7.67.2156
124114.7.67.216/29114.7.67.217 to 114.7.67.222114.7.67.2236
125114.7.67.224/29114.7.67.225 to 114.7.67.230114.7.67.2316
126114.7.67.232/29114.7.67.233 to 114.7.67.238114.7.67.2396
127114.7.67.240/29114.7.67.241 to 114.7.67.246114.7.67.2476
128114.7.67.248/29114.7.67.249 to 114.7.67.254114.7.67.2556
129114.7.68.0/29114.7.68.1 to 114.7.68.6114.7.68.76
130114.7.68.8/29114.7.68.9 to 114.7.68.14114.7.68.156
131114.7.68.16/29114.7.68.17 to 114.7.68.22114.7.68.236
132114.7.68.24/29114.7.68.25 to 114.7.68.30114.7.68.316
133114.7.68.32/29114.7.68.33 to 114.7.68.38114.7.68.396
134114.7.68.40/29114.7.68.41 to 114.7.68.46114.7.68.476
135114.7.68.48/29114.7.68.49 to 114.7.68.54114.7.68.556
136114.7.68.56/29114.7.68.57 to 114.7.68.62114.7.68.636
137114.7.68.64/29114.7.68.65 to 114.7.68.70114.7.68.716
138114.7.68.72/29114.7.68.73 to 114.7.68.78114.7.68.796
139114.7.68.80/29114.7.68.81 to 114.7.68.86114.7.68.876
140114.7.68.88/29114.7.68.89 to 114.7.68.94114.7.68.956
141114.7.68.96/29114.7.68.97 to 114.7.68.102114.7.68.1036
142114.7.68.104/29114.7.68.105 to 114.7.68.110114.7.68.1116
143114.7.68.112/29114.7.68.113 to 114.7.68.118114.7.68.1196
144114.7.68.120/29114.7.68.121 to 114.7.68.126114.7.68.1276
145114.7.68.128/29114.7.68.129 to 114.7.68.134114.7.68.1356
146114.7.68.136/29114.7.68.137 to 114.7.68.142114.7.68.1436
147114.7.68.144/29114.7.68.145 to 114.7.68.150114.7.68.1516
148114.7.68.152/29114.7.68.153 to 114.7.68.158114.7.68.1596
149114.7.68.160/29114.7.68.161 to 114.7.68.166114.7.68.1676
150114.7.68.168/29114.7.68.169 to 114.7.68.174114.7.68.1756
151114.7.68.176/29114.7.68.177 to 114.7.68.182114.7.68.1836
152114.7.68.184/29114.7.68.185 to 114.7.68.190114.7.68.1916
153114.7.68.192/29114.7.68.193 to 114.7.68.198114.7.68.1996
154114.7.68.200/29114.7.68.201 to 114.7.68.206114.7.68.2076
155114.7.68.208/29114.7.68.209 to 114.7.68.214114.7.68.2156
156114.7.68.216/29114.7.68.217 to 114.7.68.222114.7.68.2236
157114.7.68.224/29114.7.68.225 to 114.7.68.230114.7.68.2316
158114.7.68.232/29114.7.68.233 to 114.7.68.238114.7.68.2396
159114.7.68.240/29114.7.68.241 to 114.7.68.246114.7.68.2476
160114.7.68.248/29114.7.68.249 to 114.7.68.254114.7.68.2556
161114.7.69.0/29114.7.69.1 to 114.7.69.6114.7.69.76
162114.7.69.8/29114.7.69.9 to 114.7.69.14114.7.69.156
163114.7.69.16/29114.7.69.17 to 114.7.69.22114.7.69.236
164114.7.69.24/29114.7.69.25 to 114.7.69.30114.7.69.316
165114.7.69.32/29114.7.69.33 to 114.7.69.38114.7.69.396
166114.7.69.40/29114.7.69.41 to 114.7.69.46114.7.69.476
167114.7.69.48/29114.7.69.49 to 114.7.69.54114.7.69.556
168114.7.69.56/29114.7.69.57 to 114.7.69.62114.7.69.636
169114.7.69.64/29114.7.69.65 to 114.7.69.70114.7.69.716
170114.7.69.72/29114.7.69.73 to 114.7.69.78114.7.69.796
171114.7.69.80/29114.7.69.81 to 114.7.69.86114.7.69.876
172114.7.69.88/29114.7.69.89 to 114.7.69.94114.7.69.956
173114.7.69.96/29114.7.69.97 to 114.7.69.102114.7.69.1036
174114.7.69.104/29114.7.69.105 to 114.7.69.110114.7.69.1116
175114.7.69.112/29114.7.69.113 to 114.7.69.118114.7.69.1196
176114.7.69.120/29114.7.69.121 to 114.7.69.126114.7.69.1276
177114.7.69.128/29114.7.69.129 to 114.7.69.134114.7.69.1356
178114.7.69.136/29114.7.69.137 to 114.7.69.142114.7.69.1436
179114.7.69.144/29114.7.69.145 to 114.7.69.150114.7.69.1516
180114.7.69.152/29114.7.69.153 to 114.7.69.158114.7.69.1596
181114.7.69.160/29114.7.69.161 to 114.7.69.166114.7.69.1676
182114.7.69.168/29114.7.69.169 to 114.7.69.174114.7.69.1756
183114.7.69.176/29114.7.69.177 to 114.7.69.182114.7.69.1836
184114.7.69.184/29114.7.69.185 to 114.7.69.190114.7.69.1916
185114.7.69.192/29114.7.69.193 to 114.7.69.198114.7.69.1996
186114.7.69.200/29114.7.69.201 to 114.7.69.206114.7.69.2076
187114.7.69.208/29114.7.69.209 to 114.7.69.214114.7.69.2156
188114.7.69.216/29114.7.69.217 to 114.7.69.222114.7.69.2236
189114.7.69.224/29114.7.69.225 to 114.7.69.230114.7.69.2316
190114.7.69.232/29114.7.69.233 to 114.7.69.238114.7.69.2396
191114.7.69.240/29114.7.69.241 to 114.7.69.246114.7.69.2476
192114.7.69.248/29114.7.69.249 to 114.7.69.254114.7.69.2556
193114.7.70.0/29114.7.70.1 to 114.7.70.6114.7.70.76
194114.7.70.8/29114.7.70.9 to 114.7.70.14114.7.70.156
195114.7.70.16/29114.7.70.17 to 114.7.70.22114.7.70.236
196114.7.70.24/29114.7.70.25 to 114.7.70.30114.7.70.316
197114.7.70.32/29114.7.70.33 to 114.7.70.38114.7.70.396
198114.7.70.40/29114.7.70.41 to 114.7.70.46114.7.70.476
199114.7.70.48/29114.7.70.49 to 114.7.70.54114.7.70.556
200114.7.70.56/29114.7.70.57 to 114.7.70.62114.7.70.636
201114.7.70.64/29114.7.70.65 to 114.7.70.70114.7.70.716
202114.7.70.72/29114.7.70.73 to 114.7.70.78114.7.70.796
203114.7.70.80/29114.7.70.81 to 114.7.70.86114.7.70.876
204114.7.70.88/29114.7.70.89 to 114.7.70.94114.7.70.956
205114.7.70.96/29114.7.70.97 to 114.7.70.102114.7.70.1036
206114.7.70.104/29114.7.70.105 to 114.7.70.110114.7.70.1116
207114.7.70.112/29114.7.70.113 to 114.7.70.118114.7.70.1196
208114.7.70.120/29114.7.70.121 to 114.7.70.126114.7.70.1276
209114.7.70.128/29114.7.70.129 to 114.7.70.134114.7.70.1356
210114.7.70.136/29114.7.70.137 to 114.7.70.142114.7.70.1436
211114.7.70.144/29114.7.70.145 to 114.7.70.150114.7.70.1516
212114.7.70.152/29114.7.70.153 to 114.7.70.158114.7.70.1596
213114.7.70.160/29114.7.70.161 to 114.7.70.166114.7.70.1676
214114.7.70.168/29114.7.70.169 to 114.7.70.174114.7.70.1756
215114.7.70.176/29114.7.70.177 to 114.7.70.182114.7.70.1836
216114.7.70.184/29114.7.70.185 to 114.7.70.190114.7.70.1916
217114.7.70.192/29114.7.70.193 to 114.7.70.198114.7.70.1996
218114.7.70.200/29114.7.70.201 to 114.7.70.206114.7.70.2076
219114.7.70.208/29114.7.70.209 to 114.7.70.214114.7.70.2156
220114.7.70.216/29114.7.70.217 to 114.7.70.222114.7.70.2236
221114.7.70.224/29114.7.70.225 to 114.7.70.230114.7.70.2316
222114.7.70.232/29114.7.70.233 to 114.7.70.238114.7.70.2396
223114.7.70.240/29114.7.70.241 to 114.7.70.246114.7.70.2476
224114.7.70.248/29114.7.70.249 to 114.7.70.254114.7.70.2556
225114.7.71.0/29114.7.71.1 to 114.7.71.6114.7.71.76
226114.7.71.8/29114.7.71.9 to 114.7.71.14114.7.71.156
227114.7.71.16/29114.7.71.17 to 114.7.71.22114.7.71.236
228114.7.71.24/29114.7.71.25 to 114.7.71.30114.7.71.316
229114.7.71.32/29114.7.71.33 to 114.7.71.38114.7.71.396
230114.7.71.40/29114.7.71.41 to 114.7.71.46114.7.71.476
231114.7.71.48/29114.7.71.49 to 114.7.71.54114.7.71.556
232114.7.71.56/29114.7.71.57 to 114.7.71.62114.7.71.636
233114.7.71.64/29114.7.71.65 to 114.7.71.70114.7.71.716
234114.7.71.72/29114.7.71.73 to 114.7.71.78114.7.71.796
235114.7.71.80/29114.7.71.81 to 114.7.71.86114.7.71.876
236114.7.71.88/29114.7.71.89 to 114.7.71.94114.7.71.956
237114.7.71.96/29114.7.71.97 to 114.7.71.102114.7.71.1036
238114.7.71.104/29114.7.71.105 to 114.7.71.110114.7.71.1116
239114.7.71.112/29114.7.71.113 to 114.7.71.118114.7.71.1196
240114.7.71.120/29114.7.71.121 to 114.7.71.126114.7.71.1276
241114.7.71.128/29114.7.71.129 to 114.7.71.134114.7.71.1356
242114.7.71.136/29114.7.71.137 to 114.7.71.142114.7.71.1436
243114.7.71.144/29114.7.71.145 to 114.7.71.150114.7.71.1516
244114.7.71.152/29114.7.71.153 to 114.7.71.158114.7.71.1596
245114.7.71.160/29114.7.71.161 to 114.7.71.166114.7.71.1676
246114.7.71.168/29114.7.71.169 to 114.7.71.174114.7.71.1756
247114.7.71.176/29114.7.71.177 to 114.7.71.182114.7.71.1836
248114.7.71.184/29114.7.71.185 to 114.7.71.190114.7.71.1916
249114.7.71.192/29114.7.71.193 to 114.7.71.198114.7.71.1996
250114.7.71.200/29114.7.71.201 to 114.7.71.206114.7.71.2076
251114.7.71.208/29114.7.71.209 to 114.7.71.214114.7.71.2156
252114.7.71.216/29114.7.71.217 to 114.7.71.222114.7.71.2236
253114.7.71.224/29114.7.71.225 to 114.7.71.230114.7.71.2316
254114.7.71.232/29114.7.71.233 to 114.7.71.238114.7.71.2396
255114.7.71.240/29114.7.71.241 to 114.7.71.246114.7.71.2476
256114.7.71.248/29114.7.71.249 to 114.7.71.254114.7.71.2556

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

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.