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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.

Network228.16.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
228.16.0.0
Broadcast address
228.23.255.255
First usable
228.16.0.1
Last usable
228.23.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E4100000 · Integer 3826253824 to 3826778111
Reverse DNS zones
16.228.in-addr.arpa
17.228.in-addr.arpa
18.228.in-addr.arpa
19.228.in-addr.arpa
20.228.in-addr.arpa
21.228.in-addr.arpa
22.228.in-addr.arpa
23.228.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100100.00010000.00000000.00000000228.16.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11100100.00010000.00000000.00000000228.16.0.0
Broadcast11100100.00010111.11111111.11111111228.23.255.255
Split into smaller subnets/22
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

228.16.0.0/13 makes 512 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1228.16.0.0/22228.16.0.1 to 228.16.3.254228.16.3.2551,022
2228.16.4.0/22228.16.4.1 to 228.16.7.254228.16.7.2551,022
3228.16.8.0/22228.16.8.1 to 228.16.11.254228.16.11.2551,022
4228.16.12.0/22228.16.12.1 to 228.16.15.254228.16.15.2551,022
5228.16.16.0/22228.16.16.1 to 228.16.19.254228.16.19.2551,022
6228.16.20.0/22228.16.20.1 to 228.16.23.254228.16.23.2551,022
7228.16.24.0/22228.16.24.1 to 228.16.27.254228.16.27.2551,022
8228.16.28.0/22228.16.28.1 to 228.16.31.254228.16.31.2551,022
9228.16.32.0/22228.16.32.1 to 228.16.35.254228.16.35.2551,022
10228.16.36.0/22228.16.36.1 to 228.16.39.254228.16.39.2551,022
11228.16.40.0/22228.16.40.1 to 228.16.43.254228.16.43.2551,022
12228.16.44.0/22228.16.44.1 to 228.16.47.254228.16.47.2551,022
13228.16.48.0/22228.16.48.1 to 228.16.51.254228.16.51.2551,022
14228.16.52.0/22228.16.52.1 to 228.16.55.254228.16.55.2551,022
15228.16.56.0/22228.16.56.1 to 228.16.59.254228.16.59.2551,022
16228.16.60.0/22228.16.60.1 to 228.16.63.254228.16.63.2551,022
17228.16.64.0/22228.16.64.1 to 228.16.67.254228.16.67.2551,022
18228.16.68.0/22228.16.68.1 to 228.16.71.254228.16.71.2551,022
19228.16.72.0/22228.16.72.1 to 228.16.75.254228.16.75.2551,022
20228.16.76.0/22228.16.76.1 to 228.16.79.254228.16.79.2551,022
21228.16.80.0/22228.16.80.1 to 228.16.83.254228.16.83.2551,022
22228.16.84.0/22228.16.84.1 to 228.16.87.254228.16.87.2551,022
23228.16.88.0/22228.16.88.1 to 228.16.91.254228.16.91.2551,022
24228.16.92.0/22228.16.92.1 to 228.16.95.254228.16.95.2551,022
25228.16.96.0/22228.16.96.1 to 228.16.99.254228.16.99.2551,022
26228.16.100.0/22228.16.100.1 to 228.16.103.254228.16.103.2551,022
27228.16.104.0/22228.16.104.1 to 228.16.107.254228.16.107.2551,022
28228.16.108.0/22228.16.108.1 to 228.16.111.254228.16.111.2551,022
29228.16.112.0/22228.16.112.1 to 228.16.115.254228.16.115.2551,022
30228.16.116.0/22228.16.116.1 to 228.16.119.254228.16.119.2551,022
31228.16.120.0/22228.16.120.1 to 228.16.123.254228.16.123.2551,022
32228.16.124.0/22228.16.124.1 to 228.16.127.254228.16.127.2551,022
33228.16.128.0/22228.16.128.1 to 228.16.131.254228.16.131.2551,022
34228.16.132.0/22228.16.132.1 to 228.16.135.254228.16.135.2551,022
35228.16.136.0/22228.16.136.1 to 228.16.139.254228.16.139.2551,022
36228.16.140.0/22228.16.140.1 to 228.16.143.254228.16.143.2551,022
37228.16.144.0/22228.16.144.1 to 228.16.147.254228.16.147.2551,022
38228.16.148.0/22228.16.148.1 to 228.16.151.254228.16.151.2551,022
39228.16.152.0/22228.16.152.1 to 228.16.155.254228.16.155.2551,022
40228.16.156.0/22228.16.156.1 to 228.16.159.254228.16.159.2551,022
41228.16.160.0/22228.16.160.1 to 228.16.163.254228.16.163.2551,022
42228.16.164.0/22228.16.164.1 to 228.16.167.254228.16.167.2551,022
43228.16.168.0/22228.16.168.1 to 228.16.171.254228.16.171.2551,022
44228.16.172.0/22228.16.172.1 to 228.16.175.254228.16.175.2551,022
45228.16.176.0/22228.16.176.1 to 228.16.179.254228.16.179.2551,022
46228.16.180.0/22228.16.180.1 to 228.16.183.254228.16.183.2551,022
47228.16.184.0/22228.16.184.1 to 228.16.187.254228.16.187.2551,022
48228.16.188.0/22228.16.188.1 to 228.16.191.254228.16.191.2551,022
49228.16.192.0/22228.16.192.1 to 228.16.195.254228.16.195.2551,022
50228.16.196.0/22228.16.196.1 to 228.16.199.254228.16.199.2551,022
51228.16.200.0/22228.16.200.1 to 228.16.203.254228.16.203.2551,022
52228.16.204.0/22228.16.204.1 to 228.16.207.254228.16.207.2551,022
53228.16.208.0/22228.16.208.1 to 228.16.211.254228.16.211.2551,022
54228.16.212.0/22228.16.212.1 to 228.16.215.254228.16.215.2551,022
55228.16.216.0/22228.16.216.1 to 228.16.219.254228.16.219.2551,022
56228.16.220.0/22228.16.220.1 to 228.16.223.254228.16.223.2551,022
57228.16.224.0/22228.16.224.1 to 228.16.227.254228.16.227.2551,022
58228.16.228.0/22228.16.228.1 to 228.16.231.254228.16.231.2551,022
59228.16.232.0/22228.16.232.1 to 228.16.235.254228.16.235.2551,022
60228.16.236.0/22228.16.236.1 to 228.16.239.254228.16.239.2551,022
61228.16.240.0/22228.16.240.1 to 228.16.243.254228.16.243.2551,022
62228.16.244.0/22228.16.244.1 to 228.16.247.254228.16.247.2551,022
63228.16.248.0/22228.16.248.1 to 228.16.251.254228.16.251.2551,022
64228.16.252.0/22228.16.252.1 to 228.16.255.254228.16.255.2551,022
65228.17.0.0/22228.17.0.1 to 228.17.3.254228.17.3.2551,022
66228.17.4.0/22228.17.4.1 to 228.17.7.254228.17.7.2551,022
67228.17.8.0/22228.17.8.1 to 228.17.11.254228.17.11.2551,022
68228.17.12.0/22228.17.12.1 to 228.17.15.254228.17.15.2551,022
69228.17.16.0/22228.17.16.1 to 228.17.19.254228.17.19.2551,022
70228.17.20.0/22228.17.20.1 to 228.17.23.254228.17.23.2551,022
71228.17.24.0/22228.17.24.1 to 228.17.27.254228.17.27.2551,022
72228.17.28.0/22228.17.28.1 to 228.17.31.254228.17.31.2551,022
73228.17.32.0/22228.17.32.1 to 228.17.35.254228.17.35.2551,022
74228.17.36.0/22228.17.36.1 to 228.17.39.254228.17.39.2551,022
75228.17.40.0/22228.17.40.1 to 228.17.43.254228.17.43.2551,022
76228.17.44.0/22228.17.44.1 to 228.17.47.254228.17.47.2551,022
77228.17.48.0/22228.17.48.1 to 228.17.51.254228.17.51.2551,022
78228.17.52.0/22228.17.52.1 to 228.17.55.254228.17.55.2551,022
79228.17.56.0/22228.17.56.1 to 228.17.59.254228.17.59.2551,022
80228.17.60.0/22228.17.60.1 to 228.17.63.254228.17.63.2551,022
81228.17.64.0/22228.17.64.1 to 228.17.67.254228.17.67.2551,022
82228.17.68.0/22228.17.68.1 to 228.17.71.254228.17.71.2551,022
83228.17.72.0/22228.17.72.1 to 228.17.75.254228.17.75.2551,022
84228.17.76.0/22228.17.76.1 to 228.17.79.254228.17.79.2551,022
85228.17.80.0/22228.17.80.1 to 228.17.83.254228.17.83.2551,022
86228.17.84.0/22228.17.84.1 to 228.17.87.254228.17.87.2551,022
87228.17.88.0/22228.17.88.1 to 228.17.91.254228.17.91.2551,022
88228.17.92.0/22228.17.92.1 to 228.17.95.254228.17.95.2551,022
89228.17.96.0/22228.17.96.1 to 228.17.99.254228.17.99.2551,022
90228.17.100.0/22228.17.100.1 to 228.17.103.254228.17.103.2551,022
91228.17.104.0/22228.17.104.1 to 228.17.107.254228.17.107.2551,022
92228.17.108.0/22228.17.108.1 to 228.17.111.254228.17.111.2551,022
93228.17.112.0/22228.17.112.1 to 228.17.115.254228.17.115.2551,022
94228.17.116.0/22228.17.116.1 to 228.17.119.254228.17.119.2551,022
95228.17.120.0/22228.17.120.1 to 228.17.123.254228.17.123.2551,022
96228.17.124.0/22228.17.124.1 to 228.17.127.254228.17.127.2551,022
97228.17.128.0/22228.17.128.1 to 228.17.131.254228.17.131.2551,022
98228.17.132.0/22228.17.132.1 to 228.17.135.254228.17.135.2551,022
99228.17.136.0/22228.17.136.1 to 228.17.139.254228.17.139.2551,022
100228.17.140.0/22228.17.140.1 to 228.17.143.254228.17.143.2551,022
101228.17.144.0/22228.17.144.1 to 228.17.147.254228.17.147.2551,022
102228.17.148.0/22228.17.148.1 to 228.17.151.254228.17.151.2551,022
103228.17.152.0/22228.17.152.1 to 228.17.155.254228.17.155.2551,022
104228.17.156.0/22228.17.156.1 to 228.17.159.254228.17.159.2551,022
105228.17.160.0/22228.17.160.1 to 228.17.163.254228.17.163.2551,022
106228.17.164.0/22228.17.164.1 to 228.17.167.254228.17.167.2551,022
107228.17.168.0/22228.17.168.1 to 228.17.171.254228.17.171.2551,022
108228.17.172.0/22228.17.172.1 to 228.17.175.254228.17.175.2551,022
109228.17.176.0/22228.17.176.1 to 228.17.179.254228.17.179.2551,022
110228.17.180.0/22228.17.180.1 to 228.17.183.254228.17.183.2551,022
111228.17.184.0/22228.17.184.1 to 228.17.187.254228.17.187.2551,022
112228.17.188.0/22228.17.188.1 to 228.17.191.254228.17.191.2551,022
113228.17.192.0/22228.17.192.1 to 228.17.195.254228.17.195.2551,022
114228.17.196.0/22228.17.196.1 to 228.17.199.254228.17.199.2551,022
115228.17.200.0/22228.17.200.1 to 228.17.203.254228.17.203.2551,022
116228.17.204.0/22228.17.204.1 to 228.17.207.254228.17.207.2551,022
117228.17.208.0/22228.17.208.1 to 228.17.211.254228.17.211.2551,022
118228.17.212.0/22228.17.212.1 to 228.17.215.254228.17.215.2551,022
119228.17.216.0/22228.17.216.1 to 228.17.219.254228.17.219.2551,022
120228.17.220.0/22228.17.220.1 to 228.17.223.254228.17.223.2551,022
121228.17.224.0/22228.17.224.1 to 228.17.227.254228.17.227.2551,022
122228.17.228.0/22228.17.228.1 to 228.17.231.254228.17.231.2551,022
123228.17.232.0/22228.17.232.1 to 228.17.235.254228.17.235.2551,022
124228.17.236.0/22228.17.236.1 to 228.17.239.254228.17.239.2551,022
125228.17.240.0/22228.17.240.1 to 228.17.243.254228.17.243.2551,022
126228.17.244.0/22228.17.244.1 to 228.17.247.254228.17.247.2551,022
127228.17.248.0/22228.17.248.1 to 228.17.251.254228.17.251.2551,022
128228.17.252.0/22228.17.252.1 to 228.17.255.254228.17.255.2551,022
129228.18.0.0/22228.18.0.1 to 228.18.3.254228.18.3.2551,022
130228.18.4.0/22228.18.4.1 to 228.18.7.254228.18.7.2551,022
131228.18.8.0/22228.18.8.1 to 228.18.11.254228.18.11.2551,022
132228.18.12.0/22228.18.12.1 to 228.18.15.254228.18.15.2551,022
133228.18.16.0/22228.18.16.1 to 228.18.19.254228.18.19.2551,022
134228.18.20.0/22228.18.20.1 to 228.18.23.254228.18.23.2551,022
135228.18.24.0/22228.18.24.1 to 228.18.27.254228.18.27.2551,022
136228.18.28.0/22228.18.28.1 to 228.18.31.254228.18.31.2551,022
137228.18.32.0/22228.18.32.1 to 228.18.35.254228.18.35.2551,022
138228.18.36.0/22228.18.36.1 to 228.18.39.254228.18.39.2551,022
139228.18.40.0/22228.18.40.1 to 228.18.43.254228.18.43.2551,022
140228.18.44.0/22228.18.44.1 to 228.18.47.254228.18.47.2551,022
141228.18.48.0/22228.18.48.1 to 228.18.51.254228.18.51.2551,022
142228.18.52.0/22228.18.52.1 to 228.18.55.254228.18.55.2551,022
143228.18.56.0/22228.18.56.1 to 228.18.59.254228.18.59.2551,022
144228.18.60.0/22228.18.60.1 to 228.18.63.254228.18.63.2551,022
145228.18.64.0/22228.18.64.1 to 228.18.67.254228.18.67.2551,022
146228.18.68.0/22228.18.68.1 to 228.18.71.254228.18.71.2551,022
147228.18.72.0/22228.18.72.1 to 228.18.75.254228.18.75.2551,022
148228.18.76.0/22228.18.76.1 to 228.18.79.254228.18.79.2551,022
149228.18.80.0/22228.18.80.1 to 228.18.83.254228.18.83.2551,022
150228.18.84.0/22228.18.84.1 to 228.18.87.254228.18.87.2551,022
151228.18.88.0/22228.18.88.1 to 228.18.91.254228.18.91.2551,022
152228.18.92.0/22228.18.92.1 to 228.18.95.254228.18.95.2551,022
153228.18.96.0/22228.18.96.1 to 228.18.99.254228.18.99.2551,022
154228.18.100.0/22228.18.100.1 to 228.18.103.254228.18.103.2551,022
155228.18.104.0/22228.18.104.1 to 228.18.107.254228.18.107.2551,022
156228.18.108.0/22228.18.108.1 to 228.18.111.254228.18.111.2551,022
157228.18.112.0/22228.18.112.1 to 228.18.115.254228.18.115.2551,022
158228.18.116.0/22228.18.116.1 to 228.18.119.254228.18.119.2551,022
159228.18.120.0/22228.18.120.1 to 228.18.123.254228.18.123.2551,022
160228.18.124.0/22228.18.124.1 to 228.18.127.254228.18.127.2551,022
161228.18.128.0/22228.18.128.1 to 228.18.131.254228.18.131.2551,022
162228.18.132.0/22228.18.132.1 to 228.18.135.254228.18.135.2551,022
163228.18.136.0/22228.18.136.1 to 228.18.139.254228.18.139.2551,022
164228.18.140.0/22228.18.140.1 to 228.18.143.254228.18.143.2551,022
165228.18.144.0/22228.18.144.1 to 228.18.147.254228.18.147.2551,022
166228.18.148.0/22228.18.148.1 to 228.18.151.254228.18.151.2551,022
167228.18.152.0/22228.18.152.1 to 228.18.155.254228.18.155.2551,022
168228.18.156.0/22228.18.156.1 to 228.18.159.254228.18.159.2551,022
169228.18.160.0/22228.18.160.1 to 228.18.163.254228.18.163.2551,022
170228.18.164.0/22228.18.164.1 to 228.18.167.254228.18.167.2551,022
171228.18.168.0/22228.18.168.1 to 228.18.171.254228.18.171.2551,022
172228.18.172.0/22228.18.172.1 to 228.18.175.254228.18.175.2551,022
173228.18.176.0/22228.18.176.1 to 228.18.179.254228.18.179.2551,022
174228.18.180.0/22228.18.180.1 to 228.18.183.254228.18.183.2551,022
175228.18.184.0/22228.18.184.1 to 228.18.187.254228.18.187.2551,022
176228.18.188.0/22228.18.188.1 to 228.18.191.254228.18.191.2551,022
177228.18.192.0/22228.18.192.1 to 228.18.195.254228.18.195.2551,022
178228.18.196.0/22228.18.196.1 to 228.18.199.254228.18.199.2551,022
179228.18.200.0/22228.18.200.1 to 228.18.203.254228.18.203.2551,022
180228.18.204.0/22228.18.204.1 to 228.18.207.254228.18.207.2551,022
181228.18.208.0/22228.18.208.1 to 228.18.211.254228.18.211.2551,022
182228.18.212.0/22228.18.212.1 to 228.18.215.254228.18.215.2551,022
183228.18.216.0/22228.18.216.1 to 228.18.219.254228.18.219.2551,022
184228.18.220.0/22228.18.220.1 to 228.18.223.254228.18.223.2551,022
185228.18.224.0/22228.18.224.1 to 228.18.227.254228.18.227.2551,022
186228.18.228.0/22228.18.228.1 to 228.18.231.254228.18.231.2551,022
187228.18.232.0/22228.18.232.1 to 228.18.235.254228.18.235.2551,022
188228.18.236.0/22228.18.236.1 to 228.18.239.254228.18.239.2551,022
189228.18.240.0/22228.18.240.1 to 228.18.243.254228.18.243.2551,022
190228.18.244.0/22228.18.244.1 to 228.18.247.254228.18.247.2551,022
191228.18.248.0/22228.18.248.1 to 228.18.251.254228.18.251.2551,022
192228.18.252.0/22228.18.252.1 to 228.18.255.254228.18.255.2551,022
193228.19.0.0/22228.19.0.1 to 228.19.3.254228.19.3.2551,022
194228.19.4.0/22228.19.4.1 to 228.19.7.254228.19.7.2551,022
195228.19.8.0/22228.19.8.1 to 228.19.11.254228.19.11.2551,022
196228.19.12.0/22228.19.12.1 to 228.19.15.254228.19.15.2551,022
197228.19.16.0/22228.19.16.1 to 228.19.19.254228.19.19.2551,022
198228.19.20.0/22228.19.20.1 to 228.19.23.254228.19.23.2551,022
199228.19.24.0/22228.19.24.1 to 228.19.27.254228.19.27.2551,022
200228.19.28.0/22228.19.28.1 to 228.19.31.254228.19.31.2551,022
201228.19.32.0/22228.19.32.1 to 228.19.35.254228.19.35.2551,022
202228.19.36.0/22228.19.36.1 to 228.19.39.254228.19.39.2551,022
203228.19.40.0/22228.19.40.1 to 228.19.43.254228.19.43.2551,022
204228.19.44.0/22228.19.44.1 to 228.19.47.254228.19.47.2551,022
205228.19.48.0/22228.19.48.1 to 228.19.51.254228.19.51.2551,022
206228.19.52.0/22228.19.52.1 to 228.19.55.254228.19.55.2551,022
207228.19.56.0/22228.19.56.1 to 228.19.59.254228.19.59.2551,022
208228.19.60.0/22228.19.60.1 to 228.19.63.254228.19.63.2551,022
209228.19.64.0/22228.19.64.1 to 228.19.67.254228.19.67.2551,022
210228.19.68.0/22228.19.68.1 to 228.19.71.254228.19.71.2551,022
211228.19.72.0/22228.19.72.1 to 228.19.75.254228.19.75.2551,022
212228.19.76.0/22228.19.76.1 to 228.19.79.254228.19.79.2551,022
213228.19.80.0/22228.19.80.1 to 228.19.83.254228.19.83.2551,022
214228.19.84.0/22228.19.84.1 to 228.19.87.254228.19.87.2551,022
215228.19.88.0/22228.19.88.1 to 228.19.91.254228.19.91.2551,022
216228.19.92.0/22228.19.92.1 to 228.19.95.254228.19.95.2551,022
217228.19.96.0/22228.19.96.1 to 228.19.99.254228.19.99.2551,022
218228.19.100.0/22228.19.100.1 to 228.19.103.254228.19.103.2551,022
219228.19.104.0/22228.19.104.1 to 228.19.107.254228.19.107.2551,022
220228.19.108.0/22228.19.108.1 to 228.19.111.254228.19.111.2551,022
221228.19.112.0/22228.19.112.1 to 228.19.115.254228.19.115.2551,022
222228.19.116.0/22228.19.116.1 to 228.19.119.254228.19.119.2551,022
223228.19.120.0/22228.19.120.1 to 228.19.123.254228.19.123.2551,022
224228.19.124.0/22228.19.124.1 to 228.19.127.254228.19.127.2551,022
225228.19.128.0/22228.19.128.1 to 228.19.131.254228.19.131.2551,022
226228.19.132.0/22228.19.132.1 to 228.19.135.254228.19.135.2551,022
227228.19.136.0/22228.19.136.1 to 228.19.139.254228.19.139.2551,022
228228.19.140.0/22228.19.140.1 to 228.19.143.254228.19.143.2551,022
229228.19.144.0/22228.19.144.1 to 228.19.147.254228.19.147.2551,022
230228.19.148.0/22228.19.148.1 to 228.19.151.254228.19.151.2551,022
231228.19.152.0/22228.19.152.1 to 228.19.155.254228.19.155.2551,022
232228.19.156.0/22228.19.156.1 to 228.19.159.254228.19.159.2551,022
233228.19.160.0/22228.19.160.1 to 228.19.163.254228.19.163.2551,022
234228.19.164.0/22228.19.164.1 to 228.19.167.254228.19.167.2551,022
235228.19.168.0/22228.19.168.1 to 228.19.171.254228.19.171.2551,022
236228.19.172.0/22228.19.172.1 to 228.19.175.254228.19.175.2551,022
237228.19.176.0/22228.19.176.1 to 228.19.179.254228.19.179.2551,022
238228.19.180.0/22228.19.180.1 to 228.19.183.254228.19.183.2551,022
239228.19.184.0/22228.19.184.1 to 228.19.187.254228.19.187.2551,022
240228.19.188.0/22228.19.188.1 to 228.19.191.254228.19.191.2551,022
241228.19.192.0/22228.19.192.1 to 228.19.195.254228.19.195.2551,022
242228.19.196.0/22228.19.196.1 to 228.19.199.254228.19.199.2551,022
243228.19.200.0/22228.19.200.1 to 228.19.203.254228.19.203.2551,022
244228.19.204.0/22228.19.204.1 to 228.19.207.254228.19.207.2551,022
245228.19.208.0/22228.19.208.1 to 228.19.211.254228.19.211.2551,022
246228.19.212.0/22228.19.212.1 to 228.19.215.254228.19.215.2551,022
247228.19.216.0/22228.19.216.1 to 228.19.219.254228.19.219.2551,022
248228.19.220.0/22228.19.220.1 to 228.19.223.254228.19.223.2551,022
249228.19.224.0/22228.19.224.1 to 228.19.227.254228.19.227.2551,022
250228.19.228.0/22228.19.228.1 to 228.19.231.254228.19.231.2551,022
251228.19.232.0/22228.19.232.1 to 228.19.235.254228.19.235.2551,022
252228.19.236.0/22228.19.236.1 to 228.19.239.254228.19.239.2551,022
253228.19.240.0/22228.19.240.1 to 228.19.243.254228.19.243.2551,022
254228.19.244.0/22228.19.244.1 to 228.19.247.254228.19.247.2551,022
255228.19.248.0/22228.19.248.1 to 228.19.251.254228.19.251.2551,022
256228.19.252.0/22228.19.252.1 to 228.19.255.254228.19.255.2551,022

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.