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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.

Network228.0.0.0/6
Usable hosts67,108,862
Subnet mask252.0.0.0
Addresses67,108,864
Network address
228.0.0.0
Broadcast address
231.255.255.255
First usable
228.0.0.1
Last usable
231.255.255.254
Usable hosts
67,108,862 (67,108,864 less the network and broadcast addresses)
Subnet mask
252.0.0.0
Wildcard mask
3.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/6
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E4000000 · Integer 3825205248 to 3892314111
Reverse DNS zones
228.in-addr.arpa
229.in-addr.arpa
230.in-addr.arpa
231.in-addr.arpa
/6 is not on a 8-bit boundary, so it takes 4 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100100.00000000.00000000.00000000228.0.0.0
Subnet mask11111100.00000000.00000000.00000000252.0.0.0
Network11100100.00000000.00000000.00000000228.0.0.0
Broadcast11100111.11111111.11111111.11111111231.255.255.255
Split into smaller subnets/14
/7 (2)/8 (4)/9 (8)/10 (16)/11 (32)/12 (64)/13 (128)/14 (256)/15 (512)/16 (1,024)/17 (2,048)/18 (4,096)

228.0.0.0/6 makes 256 subnets of /14.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1228.0.0.0/14228.0.0.1 to 228.3.255.254228.3.255.255262,142
2228.4.0.0/14228.4.0.1 to 228.7.255.254228.7.255.255262,142
3228.8.0.0/14228.8.0.1 to 228.11.255.254228.11.255.255262,142
4228.12.0.0/14228.12.0.1 to 228.15.255.254228.15.255.255262,142
5228.16.0.0/14228.16.0.1 to 228.19.255.254228.19.255.255262,142
6228.20.0.0/14228.20.0.1 to 228.23.255.254228.23.255.255262,142
7228.24.0.0/14228.24.0.1 to 228.27.255.254228.27.255.255262,142
8228.28.0.0/14228.28.0.1 to 228.31.255.254228.31.255.255262,142
9228.32.0.0/14228.32.0.1 to 228.35.255.254228.35.255.255262,142
10228.36.0.0/14228.36.0.1 to 228.39.255.254228.39.255.255262,142
11228.40.0.0/14228.40.0.1 to 228.43.255.254228.43.255.255262,142
12228.44.0.0/14228.44.0.1 to 228.47.255.254228.47.255.255262,142
13228.48.0.0/14228.48.0.1 to 228.51.255.254228.51.255.255262,142
14228.52.0.0/14228.52.0.1 to 228.55.255.254228.55.255.255262,142
15228.56.0.0/14228.56.0.1 to 228.59.255.254228.59.255.255262,142
16228.60.0.0/14228.60.0.1 to 228.63.255.254228.63.255.255262,142
17228.64.0.0/14228.64.0.1 to 228.67.255.254228.67.255.255262,142
18228.68.0.0/14228.68.0.1 to 228.71.255.254228.71.255.255262,142
19228.72.0.0/14228.72.0.1 to 228.75.255.254228.75.255.255262,142
20228.76.0.0/14228.76.0.1 to 228.79.255.254228.79.255.255262,142
21228.80.0.0/14228.80.0.1 to 228.83.255.254228.83.255.255262,142
22228.84.0.0/14228.84.0.1 to 228.87.255.254228.87.255.255262,142
23228.88.0.0/14228.88.0.1 to 228.91.255.254228.91.255.255262,142
24228.92.0.0/14228.92.0.1 to 228.95.255.254228.95.255.255262,142
25228.96.0.0/14228.96.0.1 to 228.99.255.254228.99.255.255262,142
26228.100.0.0/14228.100.0.1 to 228.103.255.254228.103.255.255262,142
27228.104.0.0/14228.104.0.1 to 228.107.255.254228.107.255.255262,142
28228.108.0.0/14228.108.0.1 to 228.111.255.254228.111.255.255262,142
29228.112.0.0/14228.112.0.1 to 228.115.255.254228.115.255.255262,142
30228.116.0.0/14228.116.0.1 to 228.119.255.254228.119.255.255262,142
31228.120.0.0/14228.120.0.1 to 228.123.255.254228.123.255.255262,142
32228.124.0.0/14228.124.0.1 to 228.127.255.254228.127.255.255262,142
33228.128.0.0/14228.128.0.1 to 228.131.255.254228.131.255.255262,142
34228.132.0.0/14228.132.0.1 to 228.135.255.254228.135.255.255262,142
35228.136.0.0/14228.136.0.1 to 228.139.255.254228.139.255.255262,142
36228.140.0.0/14228.140.0.1 to 228.143.255.254228.143.255.255262,142
37228.144.0.0/14228.144.0.1 to 228.147.255.254228.147.255.255262,142
38228.148.0.0/14228.148.0.1 to 228.151.255.254228.151.255.255262,142
39228.152.0.0/14228.152.0.1 to 228.155.255.254228.155.255.255262,142
40228.156.0.0/14228.156.0.1 to 228.159.255.254228.159.255.255262,142
41228.160.0.0/14228.160.0.1 to 228.163.255.254228.163.255.255262,142
42228.164.0.0/14228.164.0.1 to 228.167.255.254228.167.255.255262,142
43228.168.0.0/14228.168.0.1 to 228.171.255.254228.171.255.255262,142
44228.172.0.0/14228.172.0.1 to 228.175.255.254228.175.255.255262,142
45228.176.0.0/14228.176.0.1 to 228.179.255.254228.179.255.255262,142
46228.180.0.0/14228.180.0.1 to 228.183.255.254228.183.255.255262,142
47228.184.0.0/14228.184.0.1 to 228.187.255.254228.187.255.255262,142
48228.188.0.0/14228.188.0.1 to 228.191.255.254228.191.255.255262,142
49228.192.0.0/14228.192.0.1 to 228.195.255.254228.195.255.255262,142
50228.196.0.0/14228.196.0.1 to 228.199.255.254228.199.255.255262,142
51228.200.0.0/14228.200.0.1 to 228.203.255.254228.203.255.255262,142
52228.204.0.0/14228.204.0.1 to 228.207.255.254228.207.255.255262,142
53228.208.0.0/14228.208.0.1 to 228.211.255.254228.211.255.255262,142
54228.212.0.0/14228.212.0.1 to 228.215.255.254228.215.255.255262,142
55228.216.0.0/14228.216.0.1 to 228.219.255.254228.219.255.255262,142
56228.220.0.0/14228.220.0.1 to 228.223.255.254228.223.255.255262,142
57228.224.0.0/14228.224.0.1 to 228.227.255.254228.227.255.255262,142
58228.228.0.0/14228.228.0.1 to 228.231.255.254228.231.255.255262,142
59228.232.0.0/14228.232.0.1 to 228.235.255.254228.235.255.255262,142
60228.236.0.0/14228.236.0.1 to 228.239.255.254228.239.255.255262,142
61228.240.0.0/14228.240.0.1 to 228.243.255.254228.243.255.255262,142
62228.244.0.0/14228.244.0.1 to 228.247.255.254228.247.255.255262,142
63228.248.0.0/14228.248.0.1 to 228.251.255.254228.251.255.255262,142
64228.252.0.0/14228.252.0.1 to 228.255.255.254228.255.255.255262,142
65229.0.0.0/14229.0.0.1 to 229.3.255.254229.3.255.255262,142
66229.4.0.0/14229.4.0.1 to 229.7.255.254229.7.255.255262,142
67229.8.0.0/14229.8.0.1 to 229.11.255.254229.11.255.255262,142
68229.12.0.0/14229.12.0.1 to 229.15.255.254229.15.255.255262,142
69229.16.0.0/14229.16.0.1 to 229.19.255.254229.19.255.255262,142
70229.20.0.0/14229.20.0.1 to 229.23.255.254229.23.255.255262,142
71229.24.0.0/14229.24.0.1 to 229.27.255.254229.27.255.255262,142
72229.28.0.0/14229.28.0.1 to 229.31.255.254229.31.255.255262,142
73229.32.0.0/14229.32.0.1 to 229.35.255.254229.35.255.255262,142
74229.36.0.0/14229.36.0.1 to 229.39.255.254229.39.255.255262,142
75229.40.0.0/14229.40.0.1 to 229.43.255.254229.43.255.255262,142
76229.44.0.0/14229.44.0.1 to 229.47.255.254229.47.255.255262,142
77229.48.0.0/14229.48.0.1 to 229.51.255.254229.51.255.255262,142
78229.52.0.0/14229.52.0.1 to 229.55.255.254229.55.255.255262,142
79229.56.0.0/14229.56.0.1 to 229.59.255.254229.59.255.255262,142
80229.60.0.0/14229.60.0.1 to 229.63.255.254229.63.255.255262,142
81229.64.0.0/14229.64.0.1 to 229.67.255.254229.67.255.255262,142
82229.68.0.0/14229.68.0.1 to 229.71.255.254229.71.255.255262,142
83229.72.0.0/14229.72.0.1 to 229.75.255.254229.75.255.255262,142
84229.76.0.0/14229.76.0.1 to 229.79.255.254229.79.255.255262,142
85229.80.0.0/14229.80.0.1 to 229.83.255.254229.83.255.255262,142
86229.84.0.0/14229.84.0.1 to 229.87.255.254229.87.255.255262,142
87229.88.0.0/14229.88.0.1 to 229.91.255.254229.91.255.255262,142
88229.92.0.0/14229.92.0.1 to 229.95.255.254229.95.255.255262,142
89229.96.0.0/14229.96.0.1 to 229.99.255.254229.99.255.255262,142
90229.100.0.0/14229.100.0.1 to 229.103.255.254229.103.255.255262,142
91229.104.0.0/14229.104.0.1 to 229.107.255.254229.107.255.255262,142
92229.108.0.0/14229.108.0.1 to 229.111.255.254229.111.255.255262,142
93229.112.0.0/14229.112.0.1 to 229.115.255.254229.115.255.255262,142
94229.116.0.0/14229.116.0.1 to 229.119.255.254229.119.255.255262,142
95229.120.0.0/14229.120.0.1 to 229.123.255.254229.123.255.255262,142
96229.124.0.0/14229.124.0.1 to 229.127.255.254229.127.255.255262,142
97229.128.0.0/14229.128.0.1 to 229.131.255.254229.131.255.255262,142
98229.132.0.0/14229.132.0.1 to 229.135.255.254229.135.255.255262,142
99229.136.0.0/14229.136.0.1 to 229.139.255.254229.139.255.255262,142
100229.140.0.0/14229.140.0.1 to 229.143.255.254229.143.255.255262,142
101229.144.0.0/14229.144.0.1 to 229.147.255.254229.147.255.255262,142
102229.148.0.0/14229.148.0.1 to 229.151.255.254229.151.255.255262,142
103229.152.0.0/14229.152.0.1 to 229.155.255.254229.155.255.255262,142
104229.156.0.0/14229.156.0.1 to 229.159.255.254229.159.255.255262,142
105229.160.0.0/14229.160.0.1 to 229.163.255.254229.163.255.255262,142
106229.164.0.0/14229.164.0.1 to 229.167.255.254229.167.255.255262,142
107229.168.0.0/14229.168.0.1 to 229.171.255.254229.171.255.255262,142
108229.172.0.0/14229.172.0.1 to 229.175.255.254229.175.255.255262,142
109229.176.0.0/14229.176.0.1 to 229.179.255.254229.179.255.255262,142
110229.180.0.0/14229.180.0.1 to 229.183.255.254229.183.255.255262,142
111229.184.0.0/14229.184.0.1 to 229.187.255.254229.187.255.255262,142
112229.188.0.0/14229.188.0.1 to 229.191.255.254229.191.255.255262,142
113229.192.0.0/14229.192.0.1 to 229.195.255.254229.195.255.255262,142
114229.196.0.0/14229.196.0.1 to 229.199.255.254229.199.255.255262,142
115229.200.0.0/14229.200.0.1 to 229.203.255.254229.203.255.255262,142
116229.204.0.0/14229.204.0.1 to 229.207.255.254229.207.255.255262,142
117229.208.0.0/14229.208.0.1 to 229.211.255.254229.211.255.255262,142
118229.212.0.0/14229.212.0.1 to 229.215.255.254229.215.255.255262,142
119229.216.0.0/14229.216.0.1 to 229.219.255.254229.219.255.255262,142
120229.220.0.0/14229.220.0.1 to 229.223.255.254229.223.255.255262,142
121229.224.0.0/14229.224.0.1 to 229.227.255.254229.227.255.255262,142
122229.228.0.0/14229.228.0.1 to 229.231.255.254229.231.255.255262,142
123229.232.0.0/14229.232.0.1 to 229.235.255.254229.235.255.255262,142
124229.236.0.0/14229.236.0.1 to 229.239.255.254229.239.255.255262,142
125229.240.0.0/14229.240.0.1 to 229.243.255.254229.243.255.255262,142
126229.244.0.0/14229.244.0.1 to 229.247.255.254229.247.255.255262,142
127229.248.0.0/14229.248.0.1 to 229.251.255.254229.251.255.255262,142
128229.252.0.0/14229.252.0.1 to 229.255.255.254229.255.255.255262,142
129230.0.0.0/14230.0.0.1 to 230.3.255.254230.3.255.255262,142
130230.4.0.0/14230.4.0.1 to 230.7.255.254230.7.255.255262,142
131230.8.0.0/14230.8.0.1 to 230.11.255.254230.11.255.255262,142
132230.12.0.0/14230.12.0.1 to 230.15.255.254230.15.255.255262,142
133230.16.0.0/14230.16.0.1 to 230.19.255.254230.19.255.255262,142
134230.20.0.0/14230.20.0.1 to 230.23.255.254230.23.255.255262,142
135230.24.0.0/14230.24.0.1 to 230.27.255.254230.27.255.255262,142
136230.28.0.0/14230.28.0.1 to 230.31.255.254230.31.255.255262,142
137230.32.0.0/14230.32.0.1 to 230.35.255.254230.35.255.255262,142
138230.36.0.0/14230.36.0.1 to 230.39.255.254230.39.255.255262,142
139230.40.0.0/14230.40.0.1 to 230.43.255.254230.43.255.255262,142
140230.44.0.0/14230.44.0.1 to 230.47.255.254230.47.255.255262,142
141230.48.0.0/14230.48.0.1 to 230.51.255.254230.51.255.255262,142
142230.52.0.0/14230.52.0.1 to 230.55.255.254230.55.255.255262,142
143230.56.0.0/14230.56.0.1 to 230.59.255.254230.59.255.255262,142
144230.60.0.0/14230.60.0.1 to 230.63.255.254230.63.255.255262,142
145230.64.0.0/14230.64.0.1 to 230.67.255.254230.67.255.255262,142
146230.68.0.0/14230.68.0.1 to 230.71.255.254230.71.255.255262,142
147230.72.0.0/14230.72.0.1 to 230.75.255.254230.75.255.255262,142
148230.76.0.0/14230.76.0.1 to 230.79.255.254230.79.255.255262,142
149230.80.0.0/14230.80.0.1 to 230.83.255.254230.83.255.255262,142
150230.84.0.0/14230.84.0.1 to 230.87.255.254230.87.255.255262,142
151230.88.0.0/14230.88.0.1 to 230.91.255.254230.91.255.255262,142
152230.92.0.0/14230.92.0.1 to 230.95.255.254230.95.255.255262,142
153230.96.0.0/14230.96.0.1 to 230.99.255.254230.99.255.255262,142
154230.100.0.0/14230.100.0.1 to 230.103.255.254230.103.255.255262,142
155230.104.0.0/14230.104.0.1 to 230.107.255.254230.107.255.255262,142
156230.108.0.0/14230.108.0.1 to 230.111.255.254230.111.255.255262,142
157230.112.0.0/14230.112.0.1 to 230.115.255.254230.115.255.255262,142
158230.116.0.0/14230.116.0.1 to 230.119.255.254230.119.255.255262,142
159230.120.0.0/14230.120.0.1 to 230.123.255.254230.123.255.255262,142
160230.124.0.0/14230.124.0.1 to 230.127.255.254230.127.255.255262,142
161230.128.0.0/14230.128.0.1 to 230.131.255.254230.131.255.255262,142
162230.132.0.0/14230.132.0.1 to 230.135.255.254230.135.255.255262,142
163230.136.0.0/14230.136.0.1 to 230.139.255.254230.139.255.255262,142
164230.140.0.0/14230.140.0.1 to 230.143.255.254230.143.255.255262,142
165230.144.0.0/14230.144.0.1 to 230.147.255.254230.147.255.255262,142
166230.148.0.0/14230.148.0.1 to 230.151.255.254230.151.255.255262,142
167230.152.0.0/14230.152.0.1 to 230.155.255.254230.155.255.255262,142
168230.156.0.0/14230.156.0.1 to 230.159.255.254230.159.255.255262,142
169230.160.0.0/14230.160.0.1 to 230.163.255.254230.163.255.255262,142
170230.164.0.0/14230.164.0.1 to 230.167.255.254230.167.255.255262,142
171230.168.0.0/14230.168.0.1 to 230.171.255.254230.171.255.255262,142
172230.172.0.0/14230.172.0.1 to 230.175.255.254230.175.255.255262,142
173230.176.0.0/14230.176.0.1 to 230.179.255.254230.179.255.255262,142
174230.180.0.0/14230.180.0.1 to 230.183.255.254230.183.255.255262,142
175230.184.0.0/14230.184.0.1 to 230.187.255.254230.187.255.255262,142
176230.188.0.0/14230.188.0.1 to 230.191.255.254230.191.255.255262,142
177230.192.0.0/14230.192.0.1 to 230.195.255.254230.195.255.255262,142
178230.196.0.0/14230.196.0.1 to 230.199.255.254230.199.255.255262,142
179230.200.0.0/14230.200.0.1 to 230.203.255.254230.203.255.255262,142
180230.204.0.0/14230.204.0.1 to 230.207.255.254230.207.255.255262,142
181230.208.0.0/14230.208.0.1 to 230.211.255.254230.211.255.255262,142
182230.212.0.0/14230.212.0.1 to 230.215.255.254230.215.255.255262,142
183230.216.0.0/14230.216.0.1 to 230.219.255.254230.219.255.255262,142
184230.220.0.0/14230.220.0.1 to 230.223.255.254230.223.255.255262,142
185230.224.0.0/14230.224.0.1 to 230.227.255.254230.227.255.255262,142
186230.228.0.0/14230.228.0.1 to 230.231.255.254230.231.255.255262,142
187230.232.0.0/14230.232.0.1 to 230.235.255.254230.235.255.255262,142
188230.236.0.0/14230.236.0.1 to 230.239.255.254230.239.255.255262,142
189230.240.0.0/14230.240.0.1 to 230.243.255.254230.243.255.255262,142
190230.244.0.0/14230.244.0.1 to 230.247.255.254230.247.255.255262,142
191230.248.0.0/14230.248.0.1 to 230.251.255.254230.251.255.255262,142
192230.252.0.0/14230.252.0.1 to 230.255.255.254230.255.255.255262,142
193231.0.0.0/14231.0.0.1 to 231.3.255.254231.3.255.255262,142
194231.4.0.0/14231.4.0.1 to 231.7.255.254231.7.255.255262,142
195231.8.0.0/14231.8.0.1 to 231.11.255.254231.11.255.255262,142
196231.12.0.0/14231.12.0.1 to 231.15.255.254231.15.255.255262,142
197231.16.0.0/14231.16.0.1 to 231.19.255.254231.19.255.255262,142
198231.20.0.0/14231.20.0.1 to 231.23.255.254231.23.255.255262,142
199231.24.0.0/14231.24.0.1 to 231.27.255.254231.27.255.255262,142
200231.28.0.0/14231.28.0.1 to 231.31.255.254231.31.255.255262,142
201231.32.0.0/14231.32.0.1 to 231.35.255.254231.35.255.255262,142
202231.36.0.0/14231.36.0.1 to 231.39.255.254231.39.255.255262,142
203231.40.0.0/14231.40.0.1 to 231.43.255.254231.43.255.255262,142
204231.44.0.0/14231.44.0.1 to 231.47.255.254231.47.255.255262,142
205231.48.0.0/14231.48.0.1 to 231.51.255.254231.51.255.255262,142
206231.52.0.0/14231.52.0.1 to 231.55.255.254231.55.255.255262,142
207231.56.0.0/14231.56.0.1 to 231.59.255.254231.59.255.255262,142
208231.60.0.0/14231.60.0.1 to 231.63.255.254231.63.255.255262,142
209231.64.0.0/14231.64.0.1 to 231.67.255.254231.67.255.255262,142
210231.68.0.0/14231.68.0.1 to 231.71.255.254231.71.255.255262,142
211231.72.0.0/14231.72.0.1 to 231.75.255.254231.75.255.255262,142
212231.76.0.0/14231.76.0.1 to 231.79.255.254231.79.255.255262,142
213231.80.0.0/14231.80.0.1 to 231.83.255.254231.83.255.255262,142
214231.84.0.0/14231.84.0.1 to 231.87.255.254231.87.255.255262,142
215231.88.0.0/14231.88.0.1 to 231.91.255.254231.91.255.255262,142
216231.92.0.0/14231.92.0.1 to 231.95.255.254231.95.255.255262,142
217231.96.0.0/14231.96.0.1 to 231.99.255.254231.99.255.255262,142
218231.100.0.0/14231.100.0.1 to 231.103.255.254231.103.255.255262,142
219231.104.0.0/14231.104.0.1 to 231.107.255.254231.107.255.255262,142
220231.108.0.0/14231.108.0.1 to 231.111.255.254231.111.255.255262,142
221231.112.0.0/14231.112.0.1 to 231.115.255.254231.115.255.255262,142
222231.116.0.0/14231.116.0.1 to 231.119.255.254231.119.255.255262,142
223231.120.0.0/14231.120.0.1 to 231.123.255.254231.123.255.255262,142
224231.124.0.0/14231.124.0.1 to 231.127.255.254231.127.255.255262,142
225231.128.0.0/14231.128.0.1 to 231.131.255.254231.131.255.255262,142
226231.132.0.0/14231.132.0.1 to 231.135.255.254231.135.255.255262,142
227231.136.0.0/14231.136.0.1 to 231.139.255.254231.139.255.255262,142
228231.140.0.0/14231.140.0.1 to 231.143.255.254231.143.255.255262,142
229231.144.0.0/14231.144.0.1 to 231.147.255.254231.147.255.255262,142
230231.148.0.0/14231.148.0.1 to 231.151.255.254231.151.255.255262,142
231231.152.0.0/14231.152.0.1 to 231.155.255.254231.155.255.255262,142
232231.156.0.0/14231.156.0.1 to 231.159.255.254231.159.255.255262,142
233231.160.0.0/14231.160.0.1 to 231.163.255.254231.163.255.255262,142
234231.164.0.0/14231.164.0.1 to 231.167.255.254231.167.255.255262,142
235231.168.0.0/14231.168.0.1 to 231.171.255.254231.171.255.255262,142
236231.172.0.0/14231.172.0.1 to 231.175.255.254231.175.255.255262,142
237231.176.0.0/14231.176.0.1 to 231.179.255.254231.179.255.255262,142
238231.180.0.0/14231.180.0.1 to 231.183.255.254231.183.255.255262,142
239231.184.0.0/14231.184.0.1 to 231.187.255.254231.187.255.255262,142
240231.188.0.0/14231.188.0.1 to 231.191.255.254231.191.255.255262,142
241231.192.0.0/14231.192.0.1 to 231.195.255.254231.195.255.255262,142
242231.196.0.0/14231.196.0.1 to 231.199.255.254231.199.255.255262,142
243231.200.0.0/14231.200.0.1 to 231.203.255.254231.203.255.255262,142
244231.204.0.0/14231.204.0.1 to 231.207.255.254231.207.255.255262,142
245231.208.0.0/14231.208.0.1 to 231.211.255.254231.211.255.255262,142
246231.212.0.0/14231.212.0.1 to 231.215.255.254231.215.255.255262,142
247231.216.0.0/14231.216.0.1 to 231.219.255.254231.219.255.255262,142
248231.220.0.0/14231.220.0.1 to 231.223.255.254231.223.255.255262,142
249231.224.0.0/14231.224.0.1 to 231.227.255.254231.227.255.255262,142
250231.228.0.0/14231.228.0.1 to 231.231.255.254231.231.255.255262,142
251231.232.0.0/14231.232.0.1 to 231.235.255.254231.235.255.255262,142
252231.236.0.0/14231.236.0.1 to 231.239.255.254231.239.255.255262,142
253231.240.0.0/14231.240.0.1 to 231.243.255.254231.243.255.255262,142
254231.244.0.0/14231.244.0.1 to 231.247.255.254231.247.255.255262,142
255231.248.0.0/14231.248.0.1 to 231.251.255.254231.251.255.255262,142
256231.252.0.0/14231.252.0.1 to 231.255.255.254231.255.255.255262,142

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.