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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.

Network117.167.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
117.167.0.0
Broadcast address
117.167.255.255
First usable
117.167.0.1
Last usable
117.167.255.254
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
A (default /8)
As numbers
Hex 75A70000 · Integer 1973878784 to 1973944319
Reverse DNS zone
167.117.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110101.10100111..00000000.00000000117.167.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01110101.10100111..00000000.00000000117.167.0.0
Broadcast01110101.10100111..11111111.11111111117.167.255.255
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)

117.167.0.0/16 makes 2,048 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1117.167.0.0/27117.167.0.1 to 117.167.0.30117.167.0.3130
2117.167.0.32/27117.167.0.33 to 117.167.0.62117.167.0.6330
3117.167.0.64/27117.167.0.65 to 117.167.0.94117.167.0.9530
4117.167.0.96/27117.167.0.97 to 117.167.0.126117.167.0.12730
5117.167.0.128/27117.167.0.129 to 117.167.0.158117.167.0.15930
6117.167.0.160/27117.167.0.161 to 117.167.0.190117.167.0.19130
7117.167.0.192/27117.167.0.193 to 117.167.0.222117.167.0.22330
8117.167.0.224/27117.167.0.225 to 117.167.0.254117.167.0.25530
9117.167.1.0/27117.167.1.1 to 117.167.1.30117.167.1.3130
10117.167.1.32/27117.167.1.33 to 117.167.1.62117.167.1.6330
11117.167.1.64/27117.167.1.65 to 117.167.1.94117.167.1.9530
12117.167.1.96/27117.167.1.97 to 117.167.1.126117.167.1.12730
13117.167.1.128/27117.167.1.129 to 117.167.1.158117.167.1.15930
14117.167.1.160/27117.167.1.161 to 117.167.1.190117.167.1.19130
15117.167.1.192/27117.167.1.193 to 117.167.1.222117.167.1.22330
16117.167.1.224/27117.167.1.225 to 117.167.1.254117.167.1.25530
17117.167.2.0/27117.167.2.1 to 117.167.2.30117.167.2.3130
18117.167.2.32/27117.167.2.33 to 117.167.2.62117.167.2.6330
19117.167.2.64/27117.167.2.65 to 117.167.2.94117.167.2.9530
20117.167.2.96/27117.167.2.97 to 117.167.2.126117.167.2.12730
21117.167.2.128/27117.167.2.129 to 117.167.2.158117.167.2.15930
22117.167.2.160/27117.167.2.161 to 117.167.2.190117.167.2.19130
23117.167.2.192/27117.167.2.193 to 117.167.2.222117.167.2.22330
24117.167.2.224/27117.167.2.225 to 117.167.2.254117.167.2.25530
25117.167.3.0/27117.167.3.1 to 117.167.3.30117.167.3.3130
26117.167.3.32/27117.167.3.33 to 117.167.3.62117.167.3.6330
27117.167.3.64/27117.167.3.65 to 117.167.3.94117.167.3.9530
28117.167.3.96/27117.167.3.97 to 117.167.3.126117.167.3.12730
29117.167.3.128/27117.167.3.129 to 117.167.3.158117.167.3.15930
30117.167.3.160/27117.167.3.161 to 117.167.3.190117.167.3.19130
31117.167.3.192/27117.167.3.193 to 117.167.3.222117.167.3.22330
32117.167.3.224/27117.167.3.225 to 117.167.3.254117.167.3.25530
33117.167.4.0/27117.167.4.1 to 117.167.4.30117.167.4.3130
34117.167.4.32/27117.167.4.33 to 117.167.4.62117.167.4.6330
35117.167.4.64/27117.167.4.65 to 117.167.4.94117.167.4.9530
36117.167.4.96/27117.167.4.97 to 117.167.4.126117.167.4.12730
37117.167.4.128/27117.167.4.129 to 117.167.4.158117.167.4.15930
38117.167.4.160/27117.167.4.161 to 117.167.4.190117.167.4.19130
39117.167.4.192/27117.167.4.193 to 117.167.4.222117.167.4.22330
40117.167.4.224/27117.167.4.225 to 117.167.4.254117.167.4.25530
41117.167.5.0/27117.167.5.1 to 117.167.5.30117.167.5.3130
42117.167.5.32/27117.167.5.33 to 117.167.5.62117.167.5.6330
43117.167.5.64/27117.167.5.65 to 117.167.5.94117.167.5.9530
44117.167.5.96/27117.167.5.97 to 117.167.5.126117.167.5.12730
45117.167.5.128/27117.167.5.129 to 117.167.5.158117.167.5.15930
46117.167.5.160/27117.167.5.161 to 117.167.5.190117.167.5.19130
47117.167.5.192/27117.167.5.193 to 117.167.5.222117.167.5.22330
48117.167.5.224/27117.167.5.225 to 117.167.5.254117.167.5.25530
49117.167.6.0/27117.167.6.1 to 117.167.6.30117.167.6.3130
50117.167.6.32/27117.167.6.33 to 117.167.6.62117.167.6.6330
51117.167.6.64/27117.167.6.65 to 117.167.6.94117.167.6.9530
52117.167.6.96/27117.167.6.97 to 117.167.6.126117.167.6.12730
53117.167.6.128/27117.167.6.129 to 117.167.6.158117.167.6.15930
54117.167.6.160/27117.167.6.161 to 117.167.6.190117.167.6.19130
55117.167.6.192/27117.167.6.193 to 117.167.6.222117.167.6.22330
56117.167.6.224/27117.167.6.225 to 117.167.6.254117.167.6.25530
57117.167.7.0/27117.167.7.1 to 117.167.7.30117.167.7.3130
58117.167.7.32/27117.167.7.33 to 117.167.7.62117.167.7.6330
59117.167.7.64/27117.167.7.65 to 117.167.7.94117.167.7.9530
60117.167.7.96/27117.167.7.97 to 117.167.7.126117.167.7.12730
61117.167.7.128/27117.167.7.129 to 117.167.7.158117.167.7.15930
62117.167.7.160/27117.167.7.161 to 117.167.7.190117.167.7.19130
63117.167.7.192/27117.167.7.193 to 117.167.7.222117.167.7.22330
64117.167.7.224/27117.167.7.225 to 117.167.7.254117.167.7.25530
65117.167.8.0/27117.167.8.1 to 117.167.8.30117.167.8.3130
66117.167.8.32/27117.167.8.33 to 117.167.8.62117.167.8.6330
67117.167.8.64/27117.167.8.65 to 117.167.8.94117.167.8.9530
68117.167.8.96/27117.167.8.97 to 117.167.8.126117.167.8.12730
69117.167.8.128/27117.167.8.129 to 117.167.8.158117.167.8.15930
70117.167.8.160/27117.167.8.161 to 117.167.8.190117.167.8.19130
71117.167.8.192/27117.167.8.193 to 117.167.8.222117.167.8.22330
72117.167.8.224/27117.167.8.225 to 117.167.8.254117.167.8.25530
73117.167.9.0/27117.167.9.1 to 117.167.9.30117.167.9.3130
74117.167.9.32/27117.167.9.33 to 117.167.9.62117.167.9.6330
75117.167.9.64/27117.167.9.65 to 117.167.9.94117.167.9.9530
76117.167.9.96/27117.167.9.97 to 117.167.9.126117.167.9.12730
77117.167.9.128/27117.167.9.129 to 117.167.9.158117.167.9.15930
78117.167.9.160/27117.167.9.161 to 117.167.9.190117.167.9.19130
79117.167.9.192/27117.167.9.193 to 117.167.9.222117.167.9.22330
80117.167.9.224/27117.167.9.225 to 117.167.9.254117.167.9.25530
81117.167.10.0/27117.167.10.1 to 117.167.10.30117.167.10.3130
82117.167.10.32/27117.167.10.33 to 117.167.10.62117.167.10.6330
83117.167.10.64/27117.167.10.65 to 117.167.10.94117.167.10.9530
84117.167.10.96/27117.167.10.97 to 117.167.10.126117.167.10.12730
85117.167.10.128/27117.167.10.129 to 117.167.10.158117.167.10.15930
86117.167.10.160/27117.167.10.161 to 117.167.10.190117.167.10.19130
87117.167.10.192/27117.167.10.193 to 117.167.10.222117.167.10.22330
88117.167.10.224/27117.167.10.225 to 117.167.10.254117.167.10.25530
89117.167.11.0/27117.167.11.1 to 117.167.11.30117.167.11.3130
90117.167.11.32/27117.167.11.33 to 117.167.11.62117.167.11.6330
91117.167.11.64/27117.167.11.65 to 117.167.11.94117.167.11.9530
92117.167.11.96/27117.167.11.97 to 117.167.11.126117.167.11.12730
93117.167.11.128/27117.167.11.129 to 117.167.11.158117.167.11.15930
94117.167.11.160/27117.167.11.161 to 117.167.11.190117.167.11.19130
95117.167.11.192/27117.167.11.193 to 117.167.11.222117.167.11.22330
96117.167.11.224/27117.167.11.225 to 117.167.11.254117.167.11.25530
97117.167.12.0/27117.167.12.1 to 117.167.12.30117.167.12.3130
98117.167.12.32/27117.167.12.33 to 117.167.12.62117.167.12.6330
99117.167.12.64/27117.167.12.65 to 117.167.12.94117.167.12.9530
100117.167.12.96/27117.167.12.97 to 117.167.12.126117.167.12.12730
101117.167.12.128/27117.167.12.129 to 117.167.12.158117.167.12.15930
102117.167.12.160/27117.167.12.161 to 117.167.12.190117.167.12.19130
103117.167.12.192/27117.167.12.193 to 117.167.12.222117.167.12.22330
104117.167.12.224/27117.167.12.225 to 117.167.12.254117.167.12.25530
105117.167.13.0/27117.167.13.1 to 117.167.13.30117.167.13.3130
106117.167.13.32/27117.167.13.33 to 117.167.13.62117.167.13.6330
107117.167.13.64/27117.167.13.65 to 117.167.13.94117.167.13.9530
108117.167.13.96/27117.167.13.97 to 117.167.13.126117.167.13.12730
109117.167.13.128/27117.167.13.129 to 117.167.13.158117.167.13.15930
110117.167.13.160/27117.167.13.161 to 117.167.13.190117.167.13.19130
111117.167.13.192/27117.167.13.193 to 117.167.13.222117.167.13.22330
112117.167.13.224/27117.167.13.225 to 117.167.13.254117.167.13.25530
113117.167.14.0/27117.167.14.1 to 117.167.14.30117.167.14.3130
114117.167.14.32/27117.167.14.33 to 117.167.14.62117.167.14.6330
115117.167.14.64/27117.167.14.65 to 117.167.14.94117.167.14.9530
116117.167.14.96/27117.167.14.97 to 117.167.14.126117.167.14.12730
117117.167.14.128/27117.167.14.129 to 117.167.14.158117.167.14.15930
118117.167.14.160/27117.167.14.161 to 117.167.14.190117.167.14.19130
119117.167.14.192/27117.167.14.193 to 117.167.14.222117.167.14.22330
120117.167.14.224/27117.167.14.225 to 117.167.14.254117.167.14.25530
121117.167.15.0/27117.167.15.1 to 117.167.15.30117.167.15.3130
122117.167.15.32/27117.167.15.33 to 117.167.15.62117.167.15.6330
123117.167.15.64/27117.167.15.65 to 117.167.15.94117.167.15.9530
124117.167.15.96/27117.167.15.97 to 117.167.15.126117.167.15.12730
125117.167.15.128/27117.167.15.129 to 117.167.15.158117.167.15.15930
126117.167.15.160/27117.167.15.161 to 117.167.15.190117.167.15.19130
127117.167.15.192/27117.167.15.193 to 117.167.15.222117.167.15.22330
128117.167.15.224/27117.167.15.225 to 117.167.15.254117.167.15.25530
129117.167.16.0/27117.167.16.1 to 117.167.16.30117.167.16.3130
130117.167.16.32/27117.167.16.33 to 117.167.16.62117.167.16.6330
131117.167.16.64/27117.167.16.65 to 117.167.16.94117.167.16.9530
132117.167.16.96/27117.167.16.97 to 117.167.16.126117.167.16.12730
133117.167.16.128/27117.167.16.129 to 117.167.16.158117.167.16.15930
134117.167.16.160/27117.167.16.161 to 117.167.16.190117.167.16.19130
135117.167.16.192/27117.167.16.193 to 117.167.16.222117.167.16.22330
136117.167.16.224/27117.167.16.225 to 117.167.16.254117.167.16.25530
137117.167.17.0/27117.167.17.1 to 117.167.17.30117.167.17.3130
138117.167.17.32/27117.167.17.33 to 117.167.17.62117.167.17.6330
139117.167.17.64/27117.167.17.65 to 117.167.17.94117.167.17.9530
140117.167.17.96/27117.167.17.97 to 117.167.17.126117.167.17.12730
141117.167.17.128/27117.167.17.129 to 117.167.17.158117.167.17.15930
142117.167.17.160/27117.167.17.161 to 117.167.17.190117.167.17.19130
143117.167.17.192/27117.167.17.193 to 117.167.17.222117.167.17.22330
144117.167.17.224/27117.167.17.225 to 117.167.17.254117.167.17.25530
145117.167.18.0/27117.167.18.1 to 117.167.18.30117.167.18.3130
146117.167.18.32/27117.167.18.33 to 117.167.18.62117.167.18.6330
147117.167.18.64/27117.167.18.65 to 117.167.18.94117.167.18.9530
148117.167.18.96/27117.167.18.97 to 117.167.18.126117.167.18.12730
149117.167.18.128/27117.167.18.129 to 117.167.18.158117.167.18.15930
150117.167.18.160/27117.167.18.161 to 117.167.18.190117.167.18.19130
151117.167.18.192/27117.167.18.193 to 117.167.18.222117.167.18.22330
152117.167.18.224/27117.167.18.225 to 117.167.18.254117.167.18.25530
153117.167.19.0/27117.167.19.1 to 117.167.19.30117.167.19.3130
154117.167.19.32/27117.167.19.33 to 117.167.19.62117.167.19.6330
155117.167.19.64/27117.167.19.65 to 117.167.19.94117.167.19.9530
156117.167.19.96/27117.167.19.97 to 117.167.19.126117.167.19.12730
157117.167.19.128/27117.167.19.129 to 117.167.19.158117.167.19.15930
158117.167.19.160/27117.167.19.161 to 117.167.19.190117.167.19.19130
159117.167.19.192/27117.167.19.193 to 117.167.19.222117.167.19.22330
160117.167.19.224/27117.167.19.225 to 117.167.19.254117.167.19.25530
161117.167.20.0/27117.167.20.1 to 117.167.20.30117.167.20.3130
162117.167.20.32/27117.167.20.33 to 117.167.20.62117.167.20.6330
163117.167.20.64/27117.167.20.65 to 117.167.20.94117.167.20.9530
164117.167.20.96/27117.167.20.97 to 117.167.20.126117.167.20.12730
165117.167.20.128/27117.167.20.129 to 117.167.20.158117.167.20.15930
166117.167.20.160/27117.167.20.161 to 117.167.20.190117.167.20.19130
167117.167.20.192/27117.167.20.193 to 117.167.20.222117.167.20.22330
168117.167.20.224/27117.167.20.225 to 117.167.20.254117.167.20.25530
169117.167.21.0/27117.167.21.1 to 117.167.21.30117.167.21.3130
170117.167.21.32/27117.167.21.33 to 117.167.21.62117.167.21.6330
171117.167.21.64/27117.167.21.65 to 117.167.21.94117.167.21.9530
172117.167.21.96/27117.167.21.97 to 117.167.21.126117.167.21.12730
173117.167.21.128/27117.167.21.129 to 117.167.21.158117.167.21.15930
174117.167.21.160/27117.167.21.161 to 117.167.21.190117.167.21.19130
175117.167.21.192/27117.167.21.193 to 117.167.21.222117.167.21.22330
176117.167.21.224/27117.167.21.225 to 117.167.21.254117.167.21.25530
177117.167.22.0/27117.167.22.1 to 117.167.22.30117.167.22.3130
178117.167.22.32/27117.167.22.33 to 117.167.22.62117.167.22.6330
179117.167.22.64/27117.167.22.65 to 117.167.22.94117.167.22.9530
180117.167.22.96/27117.167.22.97 to 117.167.22.126117.167.22.12730
181117.167.22.128/27117.167.22.129 to 117.167.22.158117.167.22.15930
182117.167.22.160/27117.167.22.161 to 117.167.22.190117.167.22.19130
183117.167.22.192/27117.167.22.193 to 117.167.22.222117.167.22.22330
184117.167.22.224/27117.167.22.225 to 117.167.22.254117.167.22.25530
185117.167.23.0/27117.167.23.1 to 117.167.23.30117.167.23.3130
186117.167.23.32/27117.167.23.33 to 117.167.23.62117.167.23.6330
187117.167.23.64/27117.167.23.65 to 117.167.23.94117.167.23.9530
188117.167.23.96/27117.167.23.97 to 117.167.23.126117.167.23.12730
189117.167.23.128/27117.167.23.129 to 117.167.23.158117.167.23.15930
190117.167.23.160/27117.167.23.161 to 117.167.23.190117.167.23.19130
191117.167.23.192/27117.167.23.193 to 117.167.23.222117.167.23.22330
192117.167.23.224/27117.167.23.225 to 117.167.23.254117.167.23.25530
193117.167.24.0/27117.167.24.1 to 117.167.24.30117.167.24.3130
194117.167.24.32/27117.167.24.33 to 117.167.24.62117.167.24.6330
195117.167.24.64/27117.167.24.65 to 117.167.24.94117.167.24.9530
196117.167.24.96/27117.167.24.97 to 117.167.24.126117.167.24.12730
197117.167.24.128/27117.167.24.129 to 117.167.24.158117.167.24.15930
198117.167.24.160/27117.167.24.161 to 117.167.24.190117.167.24.19130
199117.167.24.192/27117.167.24.193 to 117.167.24.222117.167.24.22330
200117.167.24.224/27117.167.24.225 to 117.167.24.254117.167.24.25530
201117.167.25.0/27117.167.25.1 to 117.167.25.30117.167.25.3130
202117.167.25.32/27117.167.25.33 to 117.167.25.62117.167.25.6330
203117.167.25.64/27117.167.25.65 to 117.167.25.94117.167.25.9530
204117.167.25.96/27117.167.25.97 to 117.167.25.126117.167.25.12730
205117.167.25.128/27117.167.25.129 to 117.167.25.158117.167.25.15930
206117.167.25.160/27117.167.25.161 to 117.167.25.190117.167.25.19130
207117.167.25.192/27117.167.25.193 to 117.167.25.222117.167.25.22330
208117.167.25.224/27117.167.25.225 to 117.167.25.254117.167.25.25530
209117.167.26.0/27117.167.26.1 to 117.167.26.30117.167.26.3130
210117.167.26.32/27117.167.26.33 to 117.167.26.62117.167.26.6330
211117.167.26.64/27117.167.26.65 to 117.167.26.94117.167.26.9530
212117.167.26.96/27117.167.26.97 to 117.167.26.126117.167.26.12730
213117.167.26.128/27117.167.26.129 to 117.167.26.158117.167.26.15930
214117.167.26.160/27117.167.26.161 to 117.167.26.190117.167.26.19130
215117.167.26.192/27117.167.26.193 to 117.167.26.222117.167.26.22330
216117.167.26.224/27117.167.26.225 to 117.167.26.254117.167.26.25530
217117.167.27.0/27117.167.27.1 to 117.167.27.30117.167.27.3130
218117.167.27.32/27117.167.27.33 to 117.167.27.62117.167.27.6330
219117.167.27.64/27117.167.27.65 to 117.167.27.94117.167.27.9530
220117.167.27.96/27117.167.27.97 to 117.167.27.126117.167.27.12730
221117.167.27.128/27117.167.27.129 to 117.167.27.158117.167.27.15930
222117.167.27.160/27117.167.27.161 to 117.167.27.190117.167.27.19130
223117.167.27.192/27117.167.27.193 to 117.167.27.222117.167.27.22330
224117.167.27.224/27117.167.27.225 to 117.167.27.254117.167.27.25530
225117.167.28.0/27117.167.28.1 to 117.167.28.30117.167.28.3130
226117.167.28.32/27117.167.28.33 to 117.167.28.62117.167.28.6330
227117.167.28.64/27117.167.28.65 to 117.167.28.94117.167.28.9530
228117.167.28.96/27117.167.28.97 to 117.167.28.126117.167.28.12730
229117.167.28.128/27117.167.28.129 to 117.167.28.158117.167.28.15930
230117.167.28.160/27117.167.28.161 to 117.167.28.190117.167.28.19130
231117.167.28.192/27117.167.28.193 to 117.167.28.222117.167.28.22330
232117.167.28.224/27117.167.28.225 to 117.167.28.254117.167.28.25530
233117.167.29.0/27117.167.29.1 to 117.167.29.30117.167.29.3130
234117.167.29.32/27117.167.29.33 to 117.167.29.62117.167.29.6330
235117.167.29.64/27117.167.29.65 to 117.167.29.94117.167.29.9530
236117.167.29.96/27117.167.29.97 to 117.167.29.126117.167.29.12730
237117.167.29.128/27117.167.29.129 to 117.167.29.158117.167.29.15930
238117.167.29.160/27117.167.29.161 to 117.167.29.190117.167.29.19130
239117.167.29.192/27117.167.29.193 to 117.167.29.222117.167.29.22330
240117.167.29.224/27117.167.29.225 to 117.167.29.254117.167.29.25530
241117.167.30.0/27117.167.30.1 to 117.167.30.30117.167.30.3130
242117.167.30.32/27117.167.30.33 to 117.167.30.62117.167.30.6330
243117.167.30.64/27117.167.30.65 to 117.167.30.94117.167.30.9530
244117.167.30.96/27117.167.30.97 to 117.167.30.126117.167.30.12730
245117.167.30.128/27117.167.30.129 to 117.167.30.158117.167.30.15930
246117.167.30.160/27117.167.30.161 to 117.167.30.190117.167.30.19130
247117.167.30.192/27117.167.30.193 to 117.167.30.222117.167.30.22330
248117.167.30.224/27117.167.30.225 to 117.167.30.254117.167.30.25530
249117.167.31.0/27117.167.31.1 to 117.167.31.30117.167.31.3130
250117.167.31.32/27117.167.31.33 to 117.167.31.62117.167.31.6330
251117.167.31.64/27117.167.31.65 to 117.167.31.94117.167.31.9530
252117.167.31.96/27117.167.31.97 to 117.167.31.126117.167.31.12730
253117.167.31.128/27117.167.31.129 to 117.167.31.158117.167.31.15930
254117.167.31.160/27117.167.31.161 to 117.167.31.190117.167.31.19130
255117.167.31.192/27117.167.31.193 to 117.167.31.222117.167.31.22330
256117.167.31.224/27117.167.31.225 to 117.167.31.254117.167.31.25530

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.