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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.

Network186.239.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
186.239.0.0
Broadcast address
186.239.255.255
First usable
186.239.0.1
Last usable
186.239.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
B (default /16)
As numbers
Hex BAEF0000 · Integer 3136225280 to 3136290815
Reverse DNS zone
239.186.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10111010.11101111..00000000.00000000186.239.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network10111010.11101111..00000000.00000000186.239.0.0
Broadcast10111010.11101111..11111111.11111111186.239.255.255
Split into smaller subnets/27
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

186.239.0.0/16 makes 2,048 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1186.239.0.0/27186.239.0.1 to 186.239.0.30186.239.0.3130
2186.239.0.32/27186.239.0.33 to 186.239.0.62186.239.0.6330
3186.239.0.64/27186.239.0.65 to 186.239.0.94186.239.0.9530
4186.239.0.96/27186.239.0.97 to 186.239.0.126186.239.0.12730
5186.239.0.128/27186.239.0.129 to 186.239.0.158186.239.0.15930
6186.239.0.160/27186.239.0.161 to 186.239.0.190186.239.0.19130
7186.239.0.192/27186.239.0.193 to 186.239.0.222186.239.0.22330
8186.239.0.224/27186.239.0.225 to 186.239.0.254186.239.0.25530
9186.239.1.0/27186.239.1.1 to 186.239.1.30186.239.1.3130
10186.239.1.32/27186.239.1.33 to 186.239.1.62186.239.1.6330
11186.239.1.64/27186.239.1.65 to 186.239.1.94186.239.1.9530
12186.239.1.96/27186.239.1.97 to 186.239.1.126186.239.1.12730
13186.239.1.128/27186.239.1.129 to 186.239.1.158186.239.1.15930
14186.239.1.160/27186.239.1.161 to 186.239.1.190186.239.1.19130
15186.239.1.192/27186.239.1.193 to 186.239.1.222186.239.1.22330
16186.239.1.224/27186.239.1.225 to 186.239.1.254186.239.1.25530
17186.239.2.0/27186.239.2.1 to 186.239.2.30186.239.2.3130
18186.239.2.32/27186.239.2.33 to 186.239.2.62186.239.2.6330
19186.239.2.64/27186.239.2.65 to 186.239.2.94186.239.2.9530
20186.239.2.96/27186.239.2.97 to 186.239.2.126186.239.2.12730
21186.239.2.128/27186.239.2.129 to 186.239.2.158186.239.2.15930
22186.239.2.160/27186.239.2.161 to 186.239.2.190186.239.2.19130
23186.239.2.192/27186.239.2.193 to 186.239.2.222186.239.2.22330
24186.239.2.224/27186.239.2.225 to 186.239.2.254186.239.2.25530
25186.239.3.0/27186.239.3.1 to 186.239.3.30186.239.3.3130
26186.239.3.32/27186.239.3.33 to 186.239.3.62186.239.3.6330
27186.239.3.64/27186.239.3.65 to 186.239.3.94186.239.3.9530
28186.239.3.96/27186.239.3.97 to 186.239.3.126186.239.3.12730
29186.239.3.128/27186.239.3.129 to 186.239.3.158186.239.3.15930
30186.239.3.160/27186.239.3.161 to 186.239.3.190186.239.3.19130
31186.239.3.192/27186.239.3.193 to 186.239.3.222186.239.3.22330
32186.239.3.224/27186.239.3.225 to 186.239.3.254186.239.3.25530
33186.239.4.0/27186.239.4.1 to 186.239.4.30186.239.4.3130
34186.239.4.32/27186.239.4.33 to 186.239.4.62186.239.4.6330
35186.239.4.64/27186.239.4.65 to 186.239.4.94186.239.4.9530
36186.239.4.96/27186.239.4.97 to 186.239.4.126186.239.4.12730
37186.239.4.128/27186.239.4.129 to 186.239.4.158186.239.4.15930
38186.239.4.160/27186.239.4.161 to 186.239.4.190186.239.4.19130
39186.239.4.192/27186.239.4.193 to 186.239.4.222186.239.4.22330
40186.239.4.224/27186.239.4.225 to 186.239.4.254186.239.4.25530
41186.239.5.0/27186.239.5.1 to 186.239.5.30186.239.5.3130
42186.239.5.32/27186.239.5.33 to 186.239.5.62186.239.5.6330
43186.239.5.64/27186.239.5.65 to 186.239.5.94186.239.5.9530
44186.239.5.96/27186.239.5.97 to 186.239.5.126186.239.5.12730
45186.239.5.128/27186.239.5.129 to 186.239.5.158186.239.5.15930
46186.239.5.160/27186.239.5.161 to 186.239.5.190186.239.5.19130
47186.239.5.192/27186.239.5.193 to 186.239.5.222186.239.5.22330
48186.239.5.224/27186.239.5.225 to 186.239.5.254186.239.5.25530
49186.239.6.0/27186.239.6.1 to 186.239.6.30186.239.6.3130
50186.239.6.32/27186.239.6.33 to 186.239.6.62186.239.6.6330
51186.239.6.64/27186.239.6.65 to 186.239.6.94186.239.6.9530
52186.239.6.96/27186.239.6.97 to 186.239.6.126186.239.6.12730
53186.239.6.128/27186.239.6.129 to 186.239.6.158186.239.6.15930
54186.239.6.160/27186.239.6.161 to 186.239.6.190186.239.6.19130
55186.239.6.192/27186.239.6.193 to 186.239.6.222186.239.6.22330
56186.239.6.224/27186.239.6.225 to 186.239.6.254186.239.6.25530
57186.239.7.0/27186.239.7.1 to 186.239.7.30186.239.7.3130
58186.239.7.32/27186.239.7.33 to 186.239.7.62186.239.7.6330
59186.239.7.64/27186.239.7.65 to 186.239.7.94186.239.7.9530
60186.239.7.96/27186.239.7.97 to 186.239.7.126186.239.7.12730
61186.239.7.128/27186.239.7.129 to 186.239.7.158186.239.7.15930
62186.239.7.160/27186.239.7.161 to 186.239.7.190186.239.7.19130
63186.239.7.192/27186.239.7.193 to 186.239.7.222186.239.7.22330
64186.239.7.224/27186.239.7.225 to 186.239.7.254186.239.7.25530
65186.239.8.0/27186.239.8.1 to 186.239.8.30186.239.8.3130
66186.239.8.32/27186.239.8.33 to 186.239.8.62186.239.8.6330
67186.239.8.64/27186.239.8.65 to 186.239.8.94186.239.8.9530
68186.239.8.96/27186.239.8.97 to 186.239.8.126186.239.8.12730
69186.239.8.128/27186.239.8.129 to 186.239.8.158186.239.8.15930
70186.239.8.160/27186.239.8.161 to 186.239.8.190186.239.8.19130
71186.239.8.192/27186.239.8.193 to 186.239.8.222186.239.8.22330
72186.239.8.224/27186.239.8.225 to 186.239.8.254186.239.8.25530
73186.239.9.0/27186.239.9.1 to 186.239.9.30186.239.9.3130
74186.239.9.32/27186.239.9.33 to 186.239.9.62186.239.9.6330
75186.239.9.64/27186.239.9.65 to 186.239.9.94186.239.9.9530
76186.239.9.96/27186.239.9.97 to 186.239.9.126186.239.9.12730
77186.239.9.128/27186.239.9.129 to 186.239.9.158186.239.9.15930
78186.239.9.160/27186.239.9.161 to 186.239.9.190186.239.9.19130
79186.239.9.192/27186.239.9.193 to 186.239.9.222186.239.9.22330
80186.239.9.224/27186.239.9.225 to 186.239.9.254186.239.9.25530
81186.239.10.0/27186.239.10.1 to 186.239.10.30186.239.10.3130
82186.239.10.32/27186.239.10.33 to 186.239.10.62186.239.10.6330
83186.239.10.64/27186.239.10.65 to 186.239.10.94186.239.10.9530
84186.239.10.96/27186.239.10.97 to 186.239.10.126186.239.10.12730
85186.239.10.128/27186.239.10.129 to 186.239.10.158186.239.10.15930
86186.239.10.160/27186.239.10.161 to 186.239.10.190186.239.10.19130
87186.239.10.192/27186.239.10.193 to 186.239.10.222186.239.10.22330
88186.239.10.224/27186.239.10.225 to 186.239.10.254186.239.10.25530
89186.239.11.0/27186.239.11.1 to 186.239.11.30186.239.11.3130
90186.239.11.32/27186.239.11.33 to 186.239.11.62186.239.11.6330
91186.239.11.64/27186.239.11.65 to 186.239.11.94186.239.11.9530
92186.239.11.96/27186.239.11.97 to 186.239.11.126186.239.11.12730
93186.239.11.128/27186.239.11.129 to 186.239.11.158186.239.11.15930
94186.239.11.160/27186.239.11.161 to 186.239.11.190186.239.11.19130
95186.239.11.192/27186.239.11.193 to 186.239.11.222186.239.11.22330
96186.239.11.224/27186.239.11.225 to 186.239.11.254186.239.11.25530
97186.239.12.0/27186.239.12.1 to 186.239.12.30186.239.12.3130
98186.239.12.32/27186.239.12.33 to 186.239.12.62186.239.12.6330
99186.239.12.64/27186.239.12.65 to 186.239.12.94186.239.12.9530
100186.239.12.96/27186.239.12.97 to 186.239.12.126186.239.12.12730
101186.239.12.128/27186.239.12.129 to 186.239.12.158186.239.12.15930
102186.239.12.160/27186.239.12.161 to 186.239.12.190186.239.12.19130
103186.239.12.192/27186.239.12.193 to 186.239.12.222186.239.12.22330
104186.239.12.224/27186.239.12.225 to 186.239.12.254186.239.12.25530
105186.239.13.0/27186.239.13.1 to 186.239.13.30186.239.13.3130
106186.239.13.32/27186.239.13.33 to 186.239.13.62186.239.13.6330
107186.239.13.64/27186.239.13.65 to 186.239.13.94186.239.13.9530
108186.239.13.96/27186.239.13.97 to 186.239.13.126186.239.13.12730
109186.239.13.128/27186.239.13.129 to 186.239.13.158186.239.13.15930
110186.239.13.160/27186.239.13.161 to 186.239.13.190186.239.13.19130
111186.239.13.192/27186.239.13.193 to 186.239.13.222186.239.13.22330
112186.239.13.224/27186.239.13.225 to 186.239.13.254186.239.13.25530
113186.239.14.0/27186.239.14.1 to 186.239.14.30186.239.14.3130
114186.239.14.32/27186.239.14.33 to 186.239.14.62186.239.14.6330
115186.239.14.64/27186.239.14.65 to 186.239.14.94186.239.14.9530
116186.239.14.96/27186.239.14.97 to 186.239.14.126186.239.14.12730
117186.239.14.128/27186.239.14.129 to 186.239.14.158186.239.14.15930
118186.239.14.160/27186.239.14.161 to 186.239.14.190186.239.14.19130
119186.239.14.192/27186.239.14.193 to 186.239.14.222186.239.14.22330
120186.239.14.224/27186.239.14.225 to 186.239.14.254186.239.14.25530
121186.239.15.0/27186.239.15.1 to 186.239.15.30186.239.15.3130
122186.239.15.32/27186.239.15.33 to 186.239.15.62186.239.15.6330
123186.239.15.64/27186.239.15.65 to 186.239.15.94186.239.15.9530
124186.239.15.96/27186.239.15.97 to 186.239.15.126186.239.15.12730
125186.239.15.128/27186.239.15.129 to 186.239.15.158186.239.15.15930
126186.239.15.160/27186.239.15.161 to 186.239.15.190186.239.15.19130
127186.239.15.192/27186.239.15.193 to 186.239.15.222186.239.15.22330
128186.239.15.224/27186.239.15.225 to 186.239.15.254186.239.15.25530
129186.239.16.0/27186.239.16.1 to 186.239.16.30186.239.16.3130
130186.239.16.32/27186.239.16.33 to 186.239.16.62186.239.16.6330
131186.239.16.64/27186.239.16.65 to 186.239.16.94186.239.16.9530
132186.239.16.96/27186.239.16.97 to 186.239.16.126186.239.16.12730
133186.239.16.128/27186.239.16.129 to 186.239.16.158186.239.16.15930
134186.239.16.160/27186.239.16.161 to 186.239.16.190186.239.16.19130
135186.239.16.192/27186.239.16.193 to 186.239.16.222186.239.16.22330
136186.239.16.224/27186.239.16.225 to 186.239.16.254186.239.16.25530
137186.239.17.0/27186.239.17.1 to 186.239.17.30186.239.17.3130
138186.239.17.32/27186.239.17.33 to 186.239.17.62186.239.17.6330
139186.239.17.64/27186.239.17.65 to 186.239.17.94186.239.17.9530
140186.239.17.96/27186.239.17.97 to 186.239.17.126186.239.17.12730
141186.239.17.128/27186.239.17.129 to 186.239.17.158186.239.17.15930
142186.239.17.160/27186.239.17.161 to 186.239.17.190186.239.17.19130
143186.239.17.192/27186.239.17.193 to 186.239.17.222186.239.17.22330
144186.239.17.224/27186.239.17.225 to 186.239.17.254186.239.17.25530
145186.239.18.0/27186.239.18.1 to 186.239.18.30186.239.18.3130
146186.239.18.32/27186.239.18.33 to 186.239.18.62186.239.18.6330
147186.239.18.64/27186.239.18.65 to 186.239.18.94186.239.18.9530
148186.239.18.96/27186.239.18.97 to 186.239.18.126186.239.18.12730
149186.239.18.128/27186.239.18.129 to 186.239.18.158186.239.18.15930
150186.239.18.160/27186.239.18.161 to 186.239.18.190186.239.18.19130
151186.239.18.192/27186.239.18.193 to 186.239.18.222186.239.18.22330
152186.239.18.224/27186.239.18.225 to 186.239.18.254186.239.18.25530
153186.239.19.0/27186.239.19.1 to 186.239.19.30186.239.19.3130
154186.239.19.32/27186.239.19.33 to 186.239.19.62186.239.19.6330
155186.239.19.64/27186.239.19.65 to 186.239.19.94186.239.19.9530
156186.239.19.96/27186.239.19.97 to 186.239.19.126186.239.19.12730
157186.239.19.128/27186.239.19.129 to 186.239.19.158186.239.19.15930
158186.239.19.160/27186.239.19.161 to 186.239.19.190186.239.19.19130
159186.239.19.192/27186.239.19.193 to 186.239.19.222186.239.19.22330
160186.239.19.224/27186.239.19.225 to 186.239.19.254186.239.19.25530
161186.239.20.0/27186.239.20.1 to 186.239.20.30186.239.20.3130
162186.239.20.32/27186.239.20.33 to 186.239.20.62186.239.20.6330
163186.239.20.64/27186.239.20.65 to 186.239.20.94186.239.20.9530
164186.239.20.96/27186.239.20.97 to 186.239.20.126186.239.20.12730
165186.239.20.128/27186.239.20.129 to 186.239.20.158186.239.20.15930
166186.239.20.160/27186.239.20.161 to 186.239.20.190186.239.20.19130
167186.239.20.192/27186.239.20.193 to 186.239.20.222186.239.20.22330
168186.239.20.224/27186.239.20.225 to 186.239.20.254186.239.20.25530
169186.239.21.0/27186.239.21.1 to 186.239.21.30186.239.21.3130
170186.239.21.32/27186.239.21.33 to 186.239.21.62186.239.21.6330
171186.239.21.64/27186.239.21.65 to 186.239.21.94186.239.21.9530
172186.239.21.96/27186.239.21.97 to 186.239.21.126186.239.21.12730
173186.239.21.128/27186.239.21.129 to 186.239.21.158186.239.21.15930
174186.239.21.160/27186.239.21.161 to 186.239.21.190186.239.21.19130
175186.239.21.192/27186.239.21.193 to 186.239.21.222186.239.21.22330
176186.239.21.224/27186.239.21.225 to 186.239.21.254186.239.21.25530
177186.239.22.0/27186.239.22.1 to 186.239.22.30186.239.22.3130
178186.239.22.32/27186.239.22.33 to 186.239.22.62186.239.22.6330
179186.239.22.64/27186.239.22.65 to 186.239.22.94186.239.22.9530
180186.239.22.96/27186.239.22.97 to 186.239.22.126186.239.22.12730
181186.239.22.128/27186.239.22.129 to 186.239.22.158186.239.22.15930
182186.239.22.160/27186.239.22.161 to 186.239.22.190186.239.22.19130
183186.239.22.192/27186.239.22.193 to 186.239.22.222186.239.22.22330
184186.239.22.224/27186.239.22.225 to 186.239.22.254186.239.22.25530
185186.239.23.0/27186.239.23.1 to 186.239.23.30186.239.23.3130
186186.239.23.32/27186.239.23.33 to 186.239.23.62186.239.23.6330
187186.239.23.64/27186.239.23.65 to 186.239.23.94186.239.23.9530
188186.239.23.96/27186.239.23.97 to 186.239.23.126186.239.23.12730
189186.239.23.128/27186.239.23.129 to 186.239.23.158186.239.23.15930
190186.239.23.160/27186.239.23.161 to 186.239.23.190186.239.23.19130
191186.239.23.192/27186.239.23.193 to 186.239.23.222186.239.23.22330
192186.239.23.224/27186.239.23.225 to 186.239.23.254186.239.23.25530
193186.239.24.0/27186.239.24.1 to 186.239.24.30186.239.24.3130
194186.239.24.32/27186.239.24.33 to 186.239.24.62186.239.24.6330
195186.239.24.64/27186.239.24.65 to 186.239.24.94186.239.24.9530
196186.239.24.96/27186.239.24.97 to 186.239.24.126186.239.24.12730
197186.239.24.128/27186.239.24.129 to 186.239.24.158186.239.24.15930
198186.239.24.160/27186.239.24.161 to 186.239.24.190186.239.24.19130
199186.239.24.192/27186.239.24.193 to 186.239.24.222186.239.24.22330
200186.239.24.224/27186.239.24.225 to 186.239.24.254186.239.24.25530
201186.239.25.0/27186.239.25.1 to 186.239.25.30186.239.25.3130
202186.239.25.32/27186.239.25.33 to 186.239.25.62186.239.25.6330
203186.239.25.64/27186.239.25.65 to 186.239.25.94186.239.25.9530
204186.239.25.96/27186.239.25.97 to 186.239.25.126186.239.25.12730
205186.239.25.128/27186.239.25.129 to 186.239.25.158186.239.25.15930
206186.239.25.160/27186.239.25.161 to 186.239.25.190186.239.25.19130
207186.239.25.192/27186.239.25.193 to 186.239.25.222186.239.25.22330
208186.239.25.224/27186.239.25.225 to 186.239.25.254186.239.25.25530
209186.239.26.0/27186.239.26.1 to 186.239.26.30186.239.26.3130
210186.239.26.32/27186.239.26.33 to 186.239.26.62186.239.26.6330
211186.239.26.64/27186.239.26.65 to 186.239.26.94186.239.26.9530
212186.239.26.96/27186.239.26.97 to 186.239.26.126186.239.26.12730
213186.239.26.128/27186.239.26.129 to 186.239.26.158186.239.26.15930
214186.239.26.160/27186.239.26.161 to 186.239.26.190186.239.26.19130
215186.239.26.192/27186.239.26.193 to 186.239.26.222186.239.26.22330
216186.239.26.224/27186.239.26.225 to 186.239.26.254186.239.26.25530
217186.239.27.0/27186.239.27.1 to 186.239.27.30186.239.27.3130
218186.239.27.32/27186.239.27.33 to 186.239.27.62186.239.27.6330
219186.239.27.64/27186.239.27.65 to 186.239.27.94186.239.27.9530
220186.239.27.96/27186.239.27.97 to 186.239.27.126186.239.27.12730
221186.239.27.128/27186.239.27.129 to 186.239.27.158186.239.27.15930
222186.239.27.160/27186.239.27.161 to 186.239.27.190186.239.27.19130
223186.239.27.192/27186.239.27.193 to 186.239.27.222186.239.27.22330
224186.239.27.224/27186.239.27.225 to 186.239.27.254186.239.27.25530
225186.239.28.0/27186.239.28.1 to 186.239.28.30186.239.28.3130
226186.239.28.32/27186.239.28.33 to 186.239.28.62186.239.28.6330
227186.239.28.64/27186.239.28.65 to 186.239.28.94186.239.28.9530
228186.239.28.96/27186.239.28.97 to 186.239.28.126186.239.28.12730
229186.239.28.128/27186.239.28.129 to 186.239.28.158186.239.28.15930
230186.239.28.160/27186.239.28.161 to 186.239.28.190186.239.28.19130
231186.239.28.192/27186.239.28.193 to 186.239.28.222186.239.28.22330
232186.239.28.224/27186.239.28.225 to 186.239.28.254186.239.28.25530
233186.239.29.0/27186.239.29.1 to 186.239.29.30186.239.29.3130
234186.239.29.32/27186.239.29.33 to 186.239.29.62186.239.29.6330
235186.239.29.64/27186.239.29.65 to 186.239.29.94186.239.29.9530
236186.239.29.96/27186.239.29.97 to 186.239.29.126186.239.29.12730
237186.239.29.128/27186.239.29.129 to 186.239.29.158186.239.29.15930
238186.239.29.160/27186.239.29.161 to 186.239.29.190186.239.29.19130
239186.239.29.192/27186.239.29.193 to 186.239.29.222186.239.29.22330
240186.239.29.224/27186.239.29.225 to 186.239.29.254186.239.29.25530
241186.239.30.0/27186.239.30.1 to 186.239.30.30186.239.30.3130
242186.239.30.32/27186.239.30.33 to 186.239.30.62186.239.30.6330
243186.239.30.64/27186.239.30.65 to 186.239.30.94186.239.30.9530
244186.239.30.96/27186.239.30.97 to 186.239.30.126186.239.30.12730
245186.239.30.128/27186.239.30.129 to 186.239.30.158186.239.30.15930
246186.239.30.160/27186.239.30.161 to 186.239.30.190186.239.30.19130
247186.239.30.192/27186.239.30.193 to 186.239.30.222186.239.30.22330
248186.239.30.224/27186.239.30.225 to 186.239.30.254186.239.30.25530
249186.239.31.0/27186.239.31.1 to 186.239.31.30186.239.31.3130
250186.239.31.32/27186.239.31.33 to 186.239.31.62186.239.31.6330
251186.239.31.64/27186.239.31.65 to 186.239.31.94186.239.31.9530
252186.239.31.96/27186.239.31.97 to 186.239.31.126186.239.31.12730
253186.239.31.128/27186.239.31.129 to 186.239.31.158186.239.31.15930
254186.239.31.160/27186.239.31.161 to 186.239.31.190186.239.31.19130
255186.239.31.192/27186.239.31.193 to 186.239.31.222186.239.31.22330
256186.239.31.224/27186.239.31.225 to 186.239.31.254186.239.31.25530

IPv4 CIDR reference (/0 to /32)

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

IPv6 prefix reference

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

Private and special ranges

IPv4

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

IPv6

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

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.