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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.

Network226.167.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
226.167.0.0
Broadcast address
226.167.127.255
First usable
226.167.0.1
Last usable
226.167.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E2A70000 · Integer 3802595328 to 3802628095
Reverse DNS zones
0.167.226.in-addr.arpa
1.167.226.in-addr.arpa
2.167.226.in-addr.arpa
3.167.226.in-addr.arpa
4.167.226.in-addr.arpa
5.167.226.in-addr.arpa
6.167.226.in-addr.arpa
7.167.226.in-addr.arpa
8.167.226.in-addr.arpa
9.167.226.in-addr.arpa
10.167.226.in-addr.arpa
11.167.226.in-addr.arpa
12.167.226.in-addr.arpa
13.167.226.in-addr.arpa
14.167.226.in-addr.arpa
15.167.226.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100010.10100111.00000000.00000000226.167.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network11100010.10100111.00000000.00000000226.167.0.0
Broadcast11100010.10100111.01111111.11111111226.167.127.255
Split into smaller subnets/27
/18 (2)/19 (4)/20 (8)/21 (16)/22 (32)/23 (64)/24 (128)/25 (256)/26 (512)/27 (1,024)/28 (2,048)/29 (4,096)

226.167.0.0/17 makes 1,024 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1226.167.0.0/27226.167.0.1 to 226.167.0.30226.167.0.3130
2226.167.0.32/27226.167.0.33 to 226.167.0.62226.167.0.6330
3226.167.0.64/27226.167.0.65 to 226.167.0.94226.167.0.9530
4226.167.0.96/27226.167.0.97 to 226.167.0.126226.167.0.12730
5226.167.0.128/27226.167.0.129 to 226.167.0.158226.167.0.15930
6226.167.0.160/27226.167.0.161 to 226.167.0.190226.167.0.19130
7226.167.0.192/27226.167.0.193 to 226.167.0.222226.167.0.22330
8226.167.0.224/27226.167.0.225 to 226.167.0.254226.167.0.25530
9226.167.1.0/27226.167.1.1 to 226.167.1.30226.167.1.3130
10226.167.1.32/27226.167.1.33 to 226.167.1.62226.167.1.6330
11226.167.1.64/27226.167.1.65 to 226.167.1.94226.167.1.9530
12226.167.1.96/27226.167.1.97 to 226.167.1.126226.167.1.12730
13226.167.1.128/27226.167.1.129 to 226.167.1.158226.167.1.15930
14226.167.1.160/27226.167.1.161 to 226.167.1.190226.167.1.19130
15226.167.1.192/27226.167.1.193 to 226.167.1.222226.167.1.22330
16226.167.1.224/27226.167.1.225 to 226.167.1.254226.167.1.25530
17226.167.2.0/27226.167.2.1 to 226.167.2.30226.167.2.3130
18226.167.2.32/27226.167.2.33 to 226.167.2.62226.167.2.6330
19226.167.2.64/27226.167.2.65 to 226.167.2.94226.167.2.9530
20226.167.2.96/27226.167.2.97 to 226.167.2.126226.167.2.12730
21226.167.2.128/27226.167.2.129 to 226.167.2.158226.167.2.15930
22226.167.2.160/27226.167.2.161 to 226.167.2.190226.167.2.19130
23226.167.2.192/27226.167.2.193 to 226.167.2.222226.167.2.22330
24226.167.2.224/27226.167.2.225 to 226.167.2.254226.167.2.25530
25226.167.3.0/27226.167.3.1 to 226.167.3.30226.167.3.3130
26226.167.3.32/27226.167.3.33 to 226.167.3.62226.167.3.6330
27226.167.3.64/27226.167.3.65 to 226.167.3.94226.167.3.9530
28226.167.3.96/27226.167.3.97 to 226.167.3.126226.167.3.12730
29226.167.3.128/27226.167.3.129 to 226.167.3.158226.167.3.15930
30226.167.3.160/27226.167.3.161 to 226.167.3.190226.167.3.19130
31226.167.3.192/27226.167.3.193 to 226.167.3.222226.167.3.22330
32226.167.3.224/27226.167.3.225 to 226.167.3.254226.167.3.25530
33226.167.4.0/27226.167.4.1 to 226.167.4.30226.167.4.3130
34226.167.4.32/27226.167.4.33 to 226.167.4.62226.167.4.6330
35226.167.4.64/27226.167.4.65 to 226.167.4.94226.167.4.9530
36226.167.4.96/27226.167.4.97 to 226.167.4.126226.167.4.12730
37226.167.4.128/27226.167.4.129 to 226.167.4.158226.167.4.15930
38226.167.4.160/27226.167.4.161 to 226.167.4.190226.167.4.19130
39226.167.4.192/27226.167.4.193 to 226.167.4.222226.167.4.22330
40226.167.4.224/27226.167.4.225 to 226.167.4.254226.167.4.25530
41226.167.5.0/27226.167.5.1 to 226.167.5.30226.167.5.3130
42226.167.5.32/27226.167.5.33 to 226.167.5.62226.167.5.6330
43226.167.5.64/27226.167.5.65 to 226.167.5.94226.167.5.9530
44226.167.5.96/27226.167.5.97 to 226.167.5.126226.167.5.12730
45226.167.5.128/27226.167.5.129 to 226.167.5.158226.167.5.15930
46226.167.5.160/27226.167.5.161 to 226.167.5.190226.167.5.19130
47226.167.5.192/27226.167.5.193 to 226.167.5.222226.167.5.22330
48226.167.5.224/27226.167.5.225 to 226.167.5.254226.167.5.25530
49226.167.6.0/27226.167.6.1 to 226.167.6.30226.167.6.3130
50226.167.6.32/27226.167.6.33 to 226.167.6.62226.167.6.6330
51226.167.6.64/27226.167.6.65 to 226.167.6.94226.167.6.9530
52226.167.6.96/27226.167.6.97 to 226.167.6.126226.167.6.12730
53226.167.6.128/27226.167.6.129 to 226.167.6.158226.167.6.15930
54226.167.6.160/27226.167.6.161 to 226.167.6.190226.167.6.19130
55226.167.6.192/27226.167.6.193 to 226.167.6.222226.167.6.22330
56226.167.6.224/27226.167.6.225 to 226.167.6.254226.167.6.25530
57226.167.7.0/27226.167.7.1 to 226.167.7.30226.167.7.3130
58226.167.7.32/27226.167.7.33 to 226.167.7.62226.167.7.6330
59226.167.7.64/27226.167.7.65 to 226.167.7.94226.167.7.9530
60226.167.7.96/27226.167.7.97 to 226.167.7.126226.167.7.12730
61226.167.7.128/27226.167.7.129 to 226.167.7.158226.167.7.15930
62226.167.7.160/27226.167.7.161 to 226.167.7.190226.167.7.19130
63226.167.7.192/27226.167.7.193 to 226.167.7.222226.167.7.22330
64226.167.7.224/27226.167.7.225 to 226.167.7.254226.167.7.25530
65226.167.8.0/27226.167.8.1 to 226.167.8.30226.167.8.3130
66226.167.8.32/27226.167.8.33 to 226.167.8.62226.167.8.6330
67226.167.8.64/27226.167.8.65 to 226.167.8.94226.167.8.9530
68226.167.8.96/27226.167.8.97 to 226.167.8.126226.167.8.12730
69226.167.8.128/27226.167.8.129 to 226.167.8.158226.167.8.15930
70226.167.8.160/27226.167.8.161 to 226.167.8.190226.167.8.19130
71226.167.8.192/27226.167.8.193 to 226.167.8.222226.167.8.22330
72226.167.8.224/27226.167.8.225 to 226.167.8.254226.167.8.25530
73226.167.9.0/27226.167.9.1 to 226.167.9.30226.167.9.3130
74226.167.9.32/27226.167.9.33 to 226.167.9.62226.167.9.6330
75226.167.9.64/27226.167.9.65 to 226.167.9.94226.167.9.9530
76226.167.9.96/27226.167.9.97 to 226.167.9.126226.167.9.12730
77226.167.9.128/27226.167.9.129 to 226.167.9.158226.167.9.15930
78226.167.9.160/27226.167.9.161 to 226.167.9.190226.167.9.19130
79226.167.9.192/27226.167.9.193 to 226.167.9.222226.167.9.22330
80226.167.9.224/27226.167.9.225 to 226.167.9.254226.167.9.25530
81226.167.10.0/27226.167.10.1 to 226.167.10.30226.167.10.3130
82226.167.10.32/27226.167.10.33 to 226.167.10.62226.167.10.6330
83226.167.10.64/27226.167.10.65 to 226.167.10.94226.167.10.9530
84226.167.10.96/27226.167.10.97 to 226.167.10.126226.167.10.12730
85226.167.10.128/27226.167.10.129 to 226.167.10.158226.167.10.15930
86226.167.10.160/27226.167.10.161 to 226.167.10.190226.167.10.19130
87226.167.10.192/27226.167.10.193 to 226.167.10.222226.167.10.22330
88226.167.10.224/27226.167.10.225 to 226.167.10.254226.167.10.25530
89226.167.11.0/27226.167.11.1 to 226.167.11.30226.167.11.3130
90226.167.11.32/27226.167.11.33 to 226.167.11.62226.167.11.6330
91226.167.11.64/27226.167.11.65 to 226.167.11.94226.167.11.9530
92226.167.11.96/27226.167.11.97 to 226.167.11.126226.167.11.12730
93226.167.11.128/27226.167.11.129 to 226.167.11.158226.167.11.15930
94226.167.11.160/27226.167.11.161 to 226.167.11.190226.167.11.19130
95226.167.11.192/27226.167.11.193 to 226.167.11.222226.167.11.22330
96226.167.11.224/27226.167.11.225 to 226.167.11.254226.167.11.25530
97226.167.12.0/27226.167.12.1 to 226.167.12.30226.167.12.3130
98226.167.12.32/27226.167.12.33 to 226.167.12.62226.167.12.6330
99226.167.12.64/27226.167.12.65 to 226.167.12.94226.167.12.9530
100226.167.12.96/27226.167.12.97 to 226.167.12.126226.167.12.12730
101226.167.12.128/27226.167.12.129 to 226.167.12.158226.167.12.15930
102226.167.12.160/27226.167.12.161 to 226.167.12.190226.167.12.19130
103226.167.12.192/27226.167.12.193 to 226.167.12.222226.167.12.22330
104226.167.12.224/27226.167.12.225 to 226.167.12.254226.167.12.25530
105226.167.13.0/27226.167.13.1 to 226.167.13.30226.167.13.3130
106226.167.13.32/27226.167.13.33 to 226.167.13.62226.167.13.6330
107226.167.13.64/27226.167.13.65 to 226.167.13.94226.167.13.9530
108226.167.13.96/27226.167.13.97 to 226.167.13.126226.167.13.12730
109226.167.13.128/27226.167.13.129 to 226.167.13.158226.167.13.15930
110226.167.13.160/27226.167.13.161 to 226.167.13.190226.167.13.19130
111226.167.13.192/27226.167.13.193 to 226.167.13.222226.167.13.22330
112226.167.13.224/27226.167.13.225 to 226.167.13.254226.167.13.25530
113226.167.14.0/27226.167.14.1 to 226.167.14.30226.167.14.3130
114226.167.14.32/27226.167.14.33 to 226.167.14.62226.167.14.6330
115226.167.14.64/27226.167.14.65 to 226.167.14.94226.167.14.9530
116226.167.14.96/27226.167.14.97 to 226.167.14.126226.167.14.12730
117226.167.14.128/27226.167.14.129 to 226.167.14.158226.167.14.15930
118226.167.14.160/27226.167.14.161 to 226.167.14.190226.167.14.19130
119226.167.14.192/27226.167.14.193 to 226.167.14.222226.167.14.22330
120226.167.14.224/27226.167.14.225 to 226.167.14.254226.167.14.25530
121226.167.15.0/27226.167.15.1 to 226.167.15.30226.167.15.3130
122226.167.15.32/27226.167.15.33 to 226.167.15.62226.167.15.6330
123226.167.15.64/27226.167.15.65 to 226.167.15.94226.167.15.9530
124226.167.15.96/27226.167.15.97 to 226.167.15.126226.167.15.12730
125226.167.15.128/27226.167.15.129 to 226.167.15.158226.167.15.15930
126226.167.15.160/27226.167.15.161 to 226.167.15.190226.167.15.19130
127226.167.15.192/27226.167.15.193 to 226.167.15.222226.167.15.22330
128226.167.15.224/27226.167.15.225 to 226.167.15.254226.167.15.25530
129226.167.16.0/27226.167.16.1 to 226.167.16.30226.167.16.3130
130226.167.16.32/27226.167.16.33 to 226.167.16.62226.167.16.6330
131226.167.16.64/27226.167.16.65 to 226.167.16.94226.167.16.9530
132226.167.16.96/27226.167.16.97 to 226.167.16.126226.167.16.12730
133226.167.16.128/27226.167.16.129 to 226.167.16.158226.167.16.15930
134226.167.16.160/27226.167.16.161 to 226.167.16.190226.167.16.19130
135226.167.16.192/27226.167.16.193 to 226.167.16.222226.167.16.22330
136226.167.16.224/27226.167.16.225 to 226.167.16.254226.167.16.25530
137226.167.17.0/27226.167.17.1 to 226.167.17.30226.167.17.3130
138226.167.17.32/27226.167.17.33 to 226.167.17.62226.167.17.6330
139226.167.17.64/27226.167.17.65 to 226.167.17.94226.167.17.9530
140226.167.17.96/27226.167.17.97 to 226.167.17.126226.167.17.12730
141226.167.17.128/27226.167.17.129 to 226.167.17.158226.167.17.15930
142226.167.17.160/27226.167.17.161 to 226.167.17.190226.167.17.19130
143226.167.17.192/27226.167.17.193 to 226.167.17.222226.167.17.22330
144226.167.17.224/27226.167.17.225 to 226.167.17.254226.167.17.25530
145226.167.18.0/27226.167.18.1 to 226.167.18.30226.167.18.3130
146226.167.18.32/27226.167.18.33 to 226.167.18.62226.167.18.6330
147226.167.18.64/27226.167.18.65 to 226.167.18.94226.167.18.9530
148226.167.18.96/27226.167.18.97 to 226.167.18.126226.167.18.12730
149226.167.18.128/27226.167.18.129 to 226.167.18.158226.167.18.15930
150226.167.18.160/27226.167.18.161 to 226.167.18.190226.167.18.19130
151226.167.18.192/27226.167.18.193 to 226.167.18.222226.167.18.22330
152226.167.18.224/27226.167.18.225 to 226.167.18.254226.167.18.25530
153226.167.19.0/27226.167.19.1 to 226.167.19.30226.167.19.3130
154226.167.19.32/27226.167.19.33 to 226.167.19.62226.167.19.6330
155226.167.19.64/27226.167.19.65 to 226.167.19.94226.167.19.9530
156226.167.19.96/27226.167.19.97 to 226.167.19.126226.167.19.12730
157226.167.19.128/27226.167.19.129 to 226.167.19.158226.167.19.15930
158226.167.19.160/27226.167.19.161 to 226.167.19.190226.167.19.19130
159226.167.19.192/27226.167.19.193 to 226.167.19.222226.167.19.22330
160226.167.19.224/27226.167.19.225 to 226.167.19.254226.167.19.25530
161226.167.20.0/27226.167.20.1 to 226.167.20.30226.167.20.3130
162226.167.20.32/27226.167.20.33 to 226.167.20.62226.167.20.6330
163226.167.20.64/27226.167.20.65 to 226.167.20.94226.167.20.9530
164226.167.20.96/27226.167.20.97 to 226.167.20.126226.167.20.12730
165226.167.20.128/27226.167.20.129 to 226.167.20.158226.167.20.15930
166226.167.20.160/27226.167.20.161 to 226.167.20.190226.167.20.19130
167226.167.20.192/27226.167.20.193 to 226.167.20.222226.167.20.22330
168226.167.20.224/27226.167.20.225 to 226.167.20.254226.167.20.25530
169226.167.21.0/27226.167.21.1 to 226.167.21.30226.167.21.3130
170226.167.21.32/27226.167.21.33 to 226.167.21.62226.167.21.6330
171226.167.21.64/27226.167.21.65 to 226.167.21.94226.167.21.9530
172226.167.21.96/27226.167.21.97 to 226.167.21.126226.167.21.12730
173226.167.21.128/27226.167.21.129 to 226.167.21.158226.167.21.15930
174226.167.21.160/27226.167.21.161 to 226.167.21.190226.167.21.19130
175226.167.21.192/27226.167.21.193 to 226.167.21.222226.167.21.22330
176226.167.21.224/27226.167.21.225 to 226.167.21.254226.167.21.25530
177226.167.22.0/27226.167.22.1 to 226.167.22.30226.167.22.3130
178226.167.22.32/27226.167.22.33 to 226.167.22.62226.167.22.6330
179226.167.22.64/27226.167.22.65 to 226.167.22.94226.167.22.9530
180226.167.22.96/27226.167.22.97 to 226.167.22.126226.167.22.12730
181226.167.22.128/27226.167.22.129 to 226.167.22.158226.167.22.15930
182226.167.22.160/27226.167.22.161 to 226.167.22.190226.167.22.19130
183226.167.22.192/27226.167.22.193 to 226.167.22.222226.167.22.22330
184226.167.22.224/27226.167.22.225 to 226.167.22.254226.167.22.25530
185226.167.23.0/27226.167.23.1 to 226.167.23.30226.167.23.3130
186226.167.23.32/27226.167.23.33 to 226.167.23.62226.167.23.6330
187226.167.23.64/27226.167.23.65 to 226.167.23.94226.167.23.9530
188226.167.23.96/27226.167.23.97 to 226.167.23.126226.167.23.12730
189226.167.23.128/27226.167.23.129 to 226.167.23.158226.167.23.15930
190226.167.23.160/27226.167.23.161 to 226.167.23.190226.167.23.19130
191226.167.23.192/27226.167.23.193 to 226.167.23.222226.167.23.22330
192226.167.23.224/27226.167.23.225 to 226.167.23.254226.167.23.25530
193226.167.24.0/27226.167.24.1 to 226.167.24.30226.167.24.3130
194226.167.24.32/27226.167.24.33 to 226.167.24.62226.167.24.6330
195226.167.24.64/27226.167.24.65 to 226.167.24.94226.167.24.9530
196226.167.24.96/27226.167.24.97 to 226.167.24.126226.167.24.12730
197226.167.24.128/27226.167.24.129 to 226.167.24.158226.167.24.15930
198226.167.24.160/27226.167.24.161 to 226.167.24.190226.167.24.19130
199226.167.24.192/27226.167.24.193 to 226.167.24.222226.167.24.22330
200226.167.24.224/27226.167.24.225 to 226.167.24.254226.167.24.25530
201226.167.25.0/27226.167.25.1 to 226.167.25.30226.167.25.3130
202226.167.25.32/27226.167.25.33 to 226.167.25.62226.167.25.6330
203226.167.25.64/27226.167.25.65 to 226.167.25.94226.167.25.9530
204226.167.25.96/27226.167.25.97 to 226.167.25.126226.167.25.12730
205226.167.25.128/27226.167.25.129 to 226.167.25.158226.167.25.15930
206226.167.25.160/27226.167.25.161 to 226.167.25.190226.167.25.19130
207226.167.25.192/27226.167.25.193 to 226.167.25.222226.167.25.22330
208226.167.25.224/27226.167.25.225 to 226.167.25.254226.167.25.25530
209226.167.26.0/27226.167.26.1 to 226.167.26.30226.167.26.3130
210226.167.26.32/27226.167.26.33 to 226.167.26.62226.167.26.6330
211226.167.26.64/27226.167.26.65 to 226.167.26.94226.167.26.9530
212226.167.26.96/27226.167.26.97 to 226.167.26.126226.167.26.12730
213226.167.26.128/27226.167.26.129 to 226.167.26.158226.167.26.15930
214226.167.26.160/27226.167.26.161 to 226.167.26.190226.167.26.19130
215226.167.26.192/27226.167.26.193 to 226.167.26.222226.167.26.22330
216226.167.26.224/27226.167.26.225 to 226.167.26.254226.167.26.25530
217226.167.27.0/27226.167.27.1 to 226.167.27.30226.167.27.3130
218226.167.27.32/27226.167.27.33 to 226.167.27.62226.167.27.6330
219226.167.27.64/27226.167.27.65 to 226.167.27.94226.167.27.9530
220226.167.27.96/27226.167.27.97 to 226.167.27.126226.167.27.12730
221226.167.27.128/27226.167.27.129 to 226.167.27.158226.167.27.15930
222226.167.27.160/27226.167.27.161 to 226.167.27.190226.167.27.19130
223226.167.27.192/27226.167.27.193 to 226.167.27.222226.167.27.22330
224226.167.27.224/27226.167.27.225 to 226.167.27.254226.167.27.25530
225226.167.28.0/27226.167.28.1 to 226.167.28.30226.167.28.3130
226226.167.28.32/27226.167.28.33 to 226.167.28.62226.167.28.6330
227226.167.28.64/27226.167.28.65 to 226.167.28.94226.167.28.9530
228226.167.28.96/27226.167.28.97 to 226.167.28.126226.167.28.12730
229226.167.28.128/27226.167.28.129 to 226.167.28.158226.167.28.15930
230226.167.28.160/27226.167.28.161 to 226.167.28.190226.167.28.19130
231226.167.28.192/27226.167.28.193 to 226.167.28.222226.167.28.22330
232226.167.28.224/27226.167.28.225 to 226.167.28.254226.167.28.25530
233226.167.29.0/27226.167.29.1 to 226.167.29.30226.167.29.3130
234226.167.29.32/27226.167.29.33 to 226.167.29.62226.167.29.6330
235226.167.29.64/27226.167.29.65 to 226.167.29.94226.167.29.9530
236226.167.29.96/27226.167.29.97 to 226.167.29.126226.167.29.12730
237226.167.29.128/27226.167.29.129 to 226.167.29.158226.167.29.15930
238226.167.29.160/27226.167.29.161 to 226.167.29.190226.167.29.19130
239226.167.29.192/27226.167.29.193 to 226.167.29.222226.167.29.22330
240226.167.29.224/27226.167.29.225 to 226.167.29.254226.167.29.25530
241226.167.30.0/27226.167.30.1 to 226.167.30.30226.167.30.3130
242226.167.30.32/27226.167.30.33 to 226.167.30.62226.167.30.6330
243226.167.30.64/27226.167.30.65 to 226.167.30.94226.167.30.9530
244226.167.30.96/27226.167.30.97 to 226.167.30.126226.167.30.12730
245226.167.30.128/27226.167.30.129 to 226.167.30.158226.167.30.15930
246226.167.30.160/27226.167.30.161 to 226.167.30.190226.167.30.19130
247226.167.30.192/27226.167.30.193 to 226.167.30.222226.167.30.22330
248226.167.30.224/27226.167.30.225 to 226.167.30.254226.167.30.25530
249226.167.31.0/27226.167.31.1 to 226.167.31.30226.167.31.3130
250226.167.31.32/27226.167.31.33 to 226.167.31.62226.167.31.6330
251226.167.31.64/27226.167.31.65 to 226.167.31.94226.167.31.9530
252226.167.31.96/27226.167.31.97 to 226.167.31.126226.167.31.12730
253226.167.31.128/27226.167.31.129 to 226.167.31.158226.167.31.15930
254226.167.31.160/27226.167.31.161 to 226.167.31.190226.167.31.19130
255226.167.31.192/27226.167.31.193 to 226.167.31.222226.167.31.22330
256226.167.31.224/27226.167.31.225 to 226.167.31.254226.167.31.25530

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.