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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.

Network230.0.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
230.0.0.0
Broadcast address
230.31.255.255
First usable
230.0.0.1
Last usable
230.31.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E6000000 · Integer 3858759680 to 3860856831
Reverse DNS zones
0.230.in-addr.arpa
1.230.in-addr.arpa
2.230.in-addr.arpa
3.230.in-addr.arpa
4.230.in-addr.arpa
5.230.in-addr.arpa
6.230.in-addr.arpa
7.230.in-addr.arpa
8.230.in-addr.arpa
9.230.in-addr.arpa
10.230.in-addr.arpa
11.230.in-addr.arpa
12.230.in-addr.arpa
13.230.in-addr.arpa
14.230.in-addr.arpa
15.230.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11100110.00000000.00000000.00000000230.0.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11100110.00000000.00000000.00000000230.0.0.0
Broadcast11100110.00011111.11111111.11111111230.31.255.255
Split into smaller subnets/22
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

230.0.0.0/11 makes 2,048 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1230.0.0.0/22230.0.0.1 to 230.0.3.254230.0.3.2551,022
2230.0.4.0/22230.0.4.1 to 230.0.7.254230.0.7.2551,022
3230.0.8.0/22230.0.8.1 to 230.0.11.254230.0.11.2551,022
4230.0.12.0/22230.0.12.1 to 230.0.15.254230.0.15.2551,022
5230.0.16.0/22230.0.16.1 to 230.0.19.254230.0.19.2551,022
6230.0.20.0/22230.0.20.1 to 230.0.23.254230.0.23.2551,022
7230.0.24.0/22230.0.24.1 to 230.0.27.254230.0.27.2551,022
8230.0.28.0/22230.0.28.1 to 230.0.31.254230.0.31.2551,022
9230.0.32.0/22230.0.32.1 to 230.0.35.254230.0.35.2551,022
10230.0.36.0/22230.0.36.1 to 230.0.39.254230.0.39.2551,022
11230.0.40.0/22230.0.40.1 to 230.0.43.254230.0.43.2551,022
12230.0.44.0/22230.0.44.1 to 230.0.47.254230.0.47.2551,022
13230.0.48.0/22230.0.48.1 to 230.0.51.254230.0.51.2551,022
14230.0.52.0/22230.0.52.1 to 230.0.55.254230.0.55.2551,022
15230.0.56.0/22230.0.56.1 to 230.0.59.254230.0.59.2551,022
16230.0.60.0/22230.0.60.1 to 230.0.63.254230.0.63.2551,022
17230.0.64.0/22230.0.64.1 to 230.0.67.254230.0.67.2551,022
18230.0.68.0/22230.0.68.1 to 230.0.71.254230.0.71.2551,022
19230.0.72.0/22230.0.72.1 to 230.0.75.254230.0.75.2551,022
20230.0.76.0/22230.0.76.1 to 230.0.79.254230.0.79.2551,022
21230.0.80.0/22230.0.80.1 to 230.0.83.254230.0.83.2551,022
22230.0.84.0/22230.0.84.1 to 230.0.87.254230.0.87.2551,022
23230.0.88.0/22230.0.88.1 to 230.0.91.254230.0.91.2551,022
24230.0.92.0/22230.0.92.1 to 230.0.95.254230.0.95.2551,022
25230.0.96.0/22230.0.96.1 to 230.0.99.254230.0.99.2551,022
26230.0.100.0/22230.0.100.1 to 230.0.103.254230.0.103.2551,022
27230.0.104.0/22230.0.104.1 to 230.0.107.254230.0.107.2551,022
28230.0.108.0/22230.0.108.1 to 230.0.111.254230.0.111.2551,022
29230.0.112.0/22230.0.112.1 to 230.0.115.254230.0.115.2551,022
30230.0.116.0/22230.0.116.1 to 230.0.119.254230.0.119.2551,022
31230.0.120.0/22230.0.120.1 to 230.0.123.254230.0.123.2551,022
32230.0.124.0/22230.0.124.1 to 230.0.127.254230.0.127.2551,022
33230.0.128.0/22230.0.128.1 to 230.0.131.254230.0.131.2551,022
34230.0.132.0/22230.0.132.1 to 230.0.135.254230.0.135.2551,022
35230.0.136.0/22230.0.136.1 to 230.0.139.254230.0.139.2551,022
36230.0.140.0/22230.0.140.1 to 230.0.143.254230.0.143.2551,022
37230.0.144.0/22230.0.144.1 to 230.0.147.254230.0.147.2551,022
38230.0.148.0/22230.0.148.1 to 230.0.151.254230.0.151.2551,022
39230.0.152.0/22230.0.152.1 to 230.0.155.254230.0.155.2551,022
40230.0.156.0/22230.0.156.1 to 230.0.159.254230.0.159.2551,022
41230.0.160.0/22230.0.160.1 to 230.0.163.254230.0.163.2551,022
42230.0.164.0/22230.0.164.1 to 230.0.167.254230.0.167.2551,022
43230.0.168.0/22230.0.168.1 to 230.0.171.254230.0.171.2551,022
44230.0.172.0/22230.0.172.1 to 230.0.175.254230.0.175.2551,022
45230.0.176.0/22230.0.176.1 to 230.0.179.254230.0.179.2551,022
46230.0.180.0/22230.0.180.1 to 230.0.183.254230.0.183.2551,022
47230.0.184.0/22230.0.184.1 to 230.0.187.254230.0.187.2551,022
48230.0.188.0/22230.0.188.1 to 230.0.191.254230.0.191.2551,022
49230.0.192.0/22230.0.192.1 to 230.0.195.254230.0.195.2551,022
50230.0.196.0/22230.0.196.1 to 230.0.199.254230.0.199.2551,022
51230.0.200.0/22230.0.200.1 to 230.0.203.254230.0.203.2551,022
52230.0.204.0/22230.0.204.1 to 230.0.207.254230.0.207.2551,022
53230.0.208.0/22230.0.208.1 to 230.0.211.254230.0.211.2551,022
54230.0.212.0/22230.0.212.1 to 230.0.215.254230.0.215.2551,022
55230.0.216.0/22230.0.216.1 to 230.0.219.254230.0.219.2551,022
56230.0.220.0/22230.0.220.1 to 230.0.223.254230.0.223.2551,022
57230.0.224.0/22230.0.224.1 to 230.0.227.254230.0.227.2551,022
58230.0.228.0/22230.0.228.1 to 230.0.231.254230.0.231.2551,022
59230.0.232.0/22230.0.232.1 to 230.0.235.254230.0.235.2551,022
60230.0.236.0/22230.0.236.1 to 230.0.239.254230.0.239.2551,022
61230.0.240.0/22230.0.240.1 to 230.0.243.254230.0.243.2551,022
62230.0.244.0/22230.0.244.1 to 230.0.247.254230.0.247.2551,022
63230.0.248.0/22230.0.248.1 to 230.0.251.254230.0.251.2551,022
64230.0.252.0/22230.0.252.1 to 230.0.255.254230.0.255.2551,022
65230.1.0.0/22230.1.0.1 to 230.1.3.254230.1.3.2551,022
66230.1.4.0/22230.1.4.1 to 230.1.7.254230.1.7.2551,022
67230.1.8.0/22230.1.8.1 to 230.1.11.254230.1.11.2551,022
68230.1.12.0/22230.1.12.1 to 230.1.15.254230.1.15.2551,022
69230.1.16.0/22230.1.16.1 to 230.1.19.254230.1.19.2551,022
70230.1.20.0/22230.1.20.1 to 230.1.23.254230.1.23.2551,022
71230.1.24.0/22230.1.24.1 to 230.1.27.254230.1.27.2551,022
72230.1.28.0/22230.1.28.1 to 230.1.31.254230.1.31.2551,022
73230.1.32.0/22230.1.32.1 to 230.1.35.254230.1.35.2551,022
74230.1.36.0/22230.1.36.1 to 230.1.39.254230.1.39.2551,022
75230.1.40.0/22230.1.40.1 to 230.1.43.254230.1.43.2551,022
76230.1.44.0/22230.1.44.1 to 230.1.47.254230.1.47.2551,022
77230.1.48.0/22230.1.48.1 to 230.1.51.254230.1.51.2551,022
78230.1.52.0/22230.1.52.1 to 230.1.55.254230.1.55.2551,022
79230.1.56.0/22230.1.56.1 to 230.1.59.254230.1.59.2551,022
80230.1.60.0/22230.1.60.1 to 230.1.63.254230.1.63.2551,022
81230.1.64.0/22230.1.64.1 to 230.1.67.254230.1.67.2551,022
82230.1.68.0/22230.1.68.1 to 230.1.71.254230.1.71.2551,022
83230.1.72.0/22230.1.72.1 to 230.1.75.254230.1.75.2551,022
84230.1.76.0/22230.1.76.1 to 230.1.79.254230.1.79.2551,022
85230.1.80.0/22230.1.80.1 to 230.1.83.254230.1.83.2551,022
86230.1.84.0/22230.1.84.1 to 230.1.87.254230.1.87.2551,022
87230.1.88.0/22230.1.88.1 to 230.1.91.254230.1.91.2551,022
88230.1.92.0/22230.1.92.1 to 230.1.95.254230.1.95.2551,022
89230.1.96.0/22230.1.96.1 to 230.1.99.254230.1.99.2551,022
90230.1.100.0/22230.1.100.1 to 230.1.103.254230.1.103.2551,022
91230.1.104.0/22230.1.104.1 to 230.1.107.254230.1.107.2551,022
92230.1.108.0/22230.1.108.1 to 230.1.111.254230.1.111.2551,022
93230.1.112.0/22230.1.112.1 to 230.1.115.254230.1.115.2551,022
94230.1.116.0/22230.1.116.1 to 230.1.119.254230.1.119.2551,022
95230.1.120.0/22230.1.120.1 to 230.1.123.254230.1.123.2551,022
96230.1.124.0/22230.1.124.1 to 230.1.127.254230.1.127.2551,022
97230.1.128.0/22230.1.128.1 to 230.1.131.254230.1.131.2551,022
98230.1.132.0/22230.1.132.1 to 230.1.135.254230.1.135.2551,022
99230.1.136.0/22230.1.136.1 to 230.1.139.254230.1.139.2551,022
100230.1.140.0/22230.1.140.1 to 230.1.143.254230.1.143.2551,022
101230.1.144.0/22230.1.144.1 to 230.1.147.254230.1.147.2551,022
102230.1.148.0/22230.1.148.1 to 230.1.151.254230.1.151.2551,022
103230.1.152.0/22230.1.152.1 to 230.1.155.254230.1.155.2551,022
104230.1.156.0/22230.1.156.1 to 230.1.159.254230.1.159.2551,022
105230.1.160.0/22230.1.160.1 to 230.1.163.254230.1.163.2551,022
106230.1.164.0/22230.1.164.1 to 230.1.167.254230.1.167.2551,022
107230.1.168.0/22230.1.168.1 to 230.1.171.254230.1.171.2551,022
108230.1.172.0/22230.1.172.1 to 230.1.175.254230.1.175.2551,022
109230.1.176.0/22230.1.176.1 to 230.1.179.254230.1.179.2551,022
110230.1.180.0/22230.1.180.1 to 230.1.183.254230.1.183.2551,022
111230.1.184.0/22230.1.184.1 to 230.1.187.254230.1.187.2551,022
112230.1.188.0/22230.1.188.1 to 230.1.191.254230.1.191.2551,022
113230.1.192.0/22230.1.192.1 to 230.1.195.254230.1.195.2551,022
114230.1.196.0/22230.1.196.1 to 230.1.199.254230.1.199.2551,022
115230.1.200.0/22230.1.200.1 to 230.1.203.254230.1.203.2551,022
116230.1.204.0/22230.1.204.1 to 230.1.207.254230.1.207.2551,022
117230.1.208.0/22230.1.208.1 to 230.1.211.254230.1.211.2551,022
118230.1.212.0/22230.1.212.1 to 230.1.215.254230.1.215.2551,022
119230.1.216.0/22230.1.216.1 to 230.1.219.254230.1.219.2551,022
120230.1.220.0/22230.1.220.1 to 230.1.223.254230.1.223.2551,022
121230.1.224.0/22230.1.224.1 to 230.1.227.254230.1.227.2551,022
122230.1.228.0/22230.1.228.1 to 230.1.231.254230.1.231.2551,022
123230.1.232.0/22230.1.232.1 to 230.1.235.254230.1.235.2551,022
124230.1.236.0/22230.1.236.1 to 230.1.239.254230.1.239.2551,022
125230.1.240.0/22230.1.240.1 to 230.1.243.254230.1.243.2551,022
126230.1.244.0/22230.1.244.1 to 230.1.247.254230.1.247.2551,022
127230.1.248.0/22230.1.248.1 to 230.1.251.254230.1.251.2551,022
128230.1.252.0/22230.1.252.1 to 230.1.255.254230.1.255.2551,022
129230.2.0.0/22230.2.0.1 to 230.2.3.254230.2.3.2551,022
130230.2.4.0/22230.2.4.1 to 230.2.7.254230.2.7.2551,022
131230.2.8.0/22230.2.8.1 to 230.2.11.254230.2.11.2551,022
132230.2.12.0/22230.2.12.1 to 230.2.15.254230.2.15.2551,022
133230.2.16.0/22230.2.16.1 to 230.2.19.254230.2.19.2551,022
134230.2.20.0/22230.2.20.1 to 230.2.23.254230.2.23.2551,022
135230.2.24.0/22230.2.24.1 to 230.2.27.254230.2.27.2551,022
136230.2.28.0/22230.2.28.1 to 230.2.31.254230.2.31.2551,022
137230.2.32.0/22230.2.32.1 to 230.2.35.254230.2.35.2551,022
138230.2.36.0/22230.2.36.1 to 230.2.39.254230.2.39.2551,022
139230.2.40.0/22230.2.40.1 to 230.2.43.254230.2.43.2551,022
140230.2.44.0/22230.2.44.1 to 230.2.47.254230.2.47.2551,022
141230.2.48.0/22230.2.48.1 to 230.2.51.254230.2.51.2551,022
142230.2.52.0/22230.2.52.1 to 230.2.55.254230.2.55.2551,022
143230.2.56.0/22230.2.56.1 to 230.2.59.254230.2.59.2551,022
144230.2.60.0/22230.2.60.1 to 230.2.63.254230.2.63.2551,022
145230.2.64.0/22230.2.64.1 to 230.2.67.254230.2.67.2551,022
146230.2.68.0/22230.2.68.1 to 230.2.71.254230.2.71.2551,022
147230.2.72.0/22230.2.72.1 to 230.2.75.254230.2.75.2551,022
148230.2.76.0/22230.2.76.1 to 230.2.79.254230.2.79.2551,022
149230.2.80.0/22230.2.80.1 to 230.2.83.254230.2.83.2551,022
150230.2.84.0/22230.2.84.1 to 230.2.87.254230.2.87.2551,022
151230.2.88.0/22230.2.88.1 to 230.2.91.254230.2.91.2551,022
152230.2.92.0/22230.2.92.1 to 230.2.95.254230.2.95.2551,022
153230.2.96.0/22230.2.96.1 to 230.2.99.254230.2.99.2551,022
154230.2.100.0/22230.2.100.1 to 230.2.103.254230.2.103.2551,022
155230.2.104.0/22230.2.104.1 to 230.2.107.254230.2.107.2551,022
156230.2.108.0/22230.2.108.1 to 230.2.111.254230.2.111.2551,022
157230.2.112.0/22230.2.112.1 to 230.2.115.254230.2.115.2551,022
158230.2.116.0/22230.2.116.1 to 230.2.119.254230.2.119.2551,022
159230.2.120.0/22230.2.120.1 to 230.2.123.254230.2.123.2551,022
160230.2.124.0/22230.2.124.1 to 230.2.127.254230.2.127.2551,022
161230.2.128.0/22230.2.128.1 to 230.2.131.254230.2.131.2551,022
162230.2.132.0/22230.2.132.1 to 230.2.135.254230.2.135.2551,022
163230.2.136.0/22230.2.136.1 to 230.2.139.254230.2.139.2551,022
164230.2.140.0/22230.2.140.1 to 230.2.143.254230.2.143.2551,022
165230.2.144.0/22230.2.144.1 to 230.2.147.254230.2.147.2551,022
166230.2.148.0/22230.2.148.1 to 230.2.151.254230.2.151.2551,022
167230.2.152.0/22230.2.152.1 to 230.2.155.254230.2.155.2551,022
168230.2.156.0/22230.2.156.1 to 230.2.159.254230.2.159.2551,022
169230.2.160.0/22230.2.160.1 to 230.2.163.254230.2.163.2551,022
170230.2.164.0/22230.2.164.1 to 230.2.167.254230.2.167.2551,022
171230.2.168.0/22230.2.168.1 to 230.2.171.254230.2.171.2551,022
172230.2.172.0/22230.2.172.1 to 230.2.175.254230.2.175.2551,022
173230.2.176.0/22230.2.176.1 to 230.2.179.254230.2.179.2551,022
174230.2.180.0/22230.2.180.1 to 230.2.183.254230.2.183.2551,022
175230.2.184.0/22230.2.184.1 to 230.2.187.254230.2.187.2551,022
176230.2.188.0/22230.2.188.1 to 230.2.191.254230.2.191.2551,022
177230.2.192.0/22230.2.192.1 to 230.2.195.254230.2.195.2551,022
178230.2.196.0/22230.2.196.1 to 230.2.199.254230.2.199.2551,022
179230.2.200.0/22230.2.200.1 to 230.2.203.254230.2.203.2551,022
180230.2.204.0/22230.2.204.1 to 230.2.207.254230.2.207.2551,022
181230.2.208.0/22230.2.208.1 to 230.2.211.254230.2.211.2551,022
182230.2.212.0/22230.2.212.1 to 230.2.215.254230.2.215.2551,022
183230.2.216.0/22230.2.216.1 to 230.2.219.254230.2.219.2551,022
184230.2.220.0/22230.2.220.1 to 230.2.223.254230.2.223.2551,022
185230.2.224.0/22230.2.224.1 to 230.2.227.254230.2.227.2551,022
186230.2.228.0/22230.2.228.1 to 230.2.231.254230.2.231.2551,022
187230.2.232.0/22230.2.232.1 to 230.2.235.254230.2.235.2551,022
188230.2.236.0/22230.2.236.1 to 230.2.239.254230.2.239.2551,022
189230.2.240.0/22230.2.240.1 to 230.2.243.254230.2.243.2551,022
190230.2.244.0/22230.2.244.1 to 230.2.247.254230.2.247.2551,022
191230.2.248.0/22230.2.248.1 to 230.2.251.254230.2.251.2551,022
192230.2.252.0/22230.2.252.1 to 230.2.255.254230.2.255.2551,022
193230.3.0.0/22230.3.0.1 to 230.3.3.254230.3.3.2551,022
194230.3.4.0/22230.3.4.1 to 230.3.7.254230.3.7.2551,022
195230.3.8.0/22230.3.8.1 to 230.3.11.254230.3.11.2551,022
196230.3.12.0/22230.3.12.1 to 230.3.15.254230.3.15.2551,022
197230.3.16.0/22230.3.16.1 to 230.3.19.254230.3.19.2551,022
198230.3.20.0/22230.3.20.1 to 230.3.23.254230.3.23.2551,022
199230.3.24.0/22230.3.24.1 to 230.3.27.254230.3.27.2551,022
200230.3.28.0/22230.3.28.1 to 230.3.31.254230.3.31.2551,022
201230.3.32.0/22230.3.32.1 to 230.3.35.254230.3.35.2551,022
202230.3.36.0/22230.3.36.1 to 230.3.39.254230.3.39.2551,022
203230.3.40.0/22230.3.40.1 to 230.3.43.254230.3.43.2551,022
204230.3.44.0/22230.3.44.1 to 230.3.47.254230.3.47.2551,022
205230.3.48.0/22230.3.48.1 to 230.3.51.254230.3.51.2551,022
206230.3.52.0/22230.3.52.1 to 230.3.55.254230.3.55.2551,022
207230.3.56.0/22230.3.56.1 to 230.3.59.254230.3.59.2551,022
208230.3.60.0/22230.3.60.1 to 230.3.63.254230.3.63.2551,022
209230.3.64.0/22230.3.64.1 to 230.3.67.254230.3.67.2551,022
210230.3.68.0/22230.3.68.1 to 230.3.71.254230.3.71.2551,022
211230.3.72.0/22230.3.72.1 to 230.3.75.254230.3.75.2551,022
212230.3.76.0/22230.3.76.1 to 230.3.79.254230.3.79.2551,022
213230.3.80.0/22230.3.80.1 to 230.3.83.254230.3.83.2551,022
214230.3.84.0/22230.3.84.1 to 230.3.87.254230.3.87.2551,022
215230.3.88.0/22230.3.88.1 to 230.3.91.254230.3.91.2551,022
216230.3.92.0/22230.3.92.1 to 230.3.95.254230.3.95.2551,022
217230.3.96.0/22230.3.96.1 to 230.3.99.254230.3.99.2551,022
218230.3.100.0/22230.3.100.1 to 230.3.103.254230.3.103.2551,022
219230.3.104.0/22230.3.104.1 to 230.3.107.254230.3.107.2551,022
220230.3.108.0/22230.3.108.1 to 230.3.111.254230.3.111.2551,022
221230.3.112.0/22230.3.112.1 to 230.3.115.254230.3.115.2551,022
222230.3.116.0/22230.3.116.1 to 230.3.119.254230.3.119.2551,022
223230.3.120.0/22230.3.120.1 to 230.3.123.254230.3.123.2551,022
224230.3.124.0/22230.3.124.1 to 230.3.127.254230.3.127.2551,022
225230.3.128.0/22230.3.128.1 to 230.3.131.254230.3.131.2551,022
226230.3.132.0/22230.3.132.1 to 230.3.135.254230.3.135.2551,022
227230.3.136.0/22230.3.136.1 to 230.3.139.254230.3.139.2551,022
228230.3.140.0/22230.3.140.1 to 230.3.143.254230.3.143.2551,022
229230.3.144.0/22230.3.144.1 to 230.3.147.254230.3.147.2551,022
230230.3.148.0/22230.3.148.1 to 230.3.151.254230.3.151.2551,022
231230.3.152.0/22230.3.152.1 to 230.3.155.254230.3.155.2551,022
232230.3.156.0/22230.3.156.1 to 230.3.159.254230.3.159.2551,022
233230.3.160.0/22230.3.160.1 to 230.3.163.254230.3.163.2551,022
234230.3.164.0/22230.3.164.1 to 230.3.167.254230.3.167.2551,022
235230.3.168.0/22230.3.168.1 to 230.3.171.254230.3.171.2551,022
236230.3.172.0/22230.3.172.1 to 230.3.175.254230.3.175.2551,022
237230.3.176.0/22230.3.176.1 to 230.3.179.254230.3.179.2551,022
238230.3.180.0/22230.3.180.1 to 230.3.183.254230.3.183.2551,022
239230.3.184.0/22230.3.184.1 to 230.3.187.254230.3.187.2551,022
240230.3.188.0/22230.3.188.1 to 230.3.191.254230.3.191.2551,022
241230.3.192.0/22230.3.192.1 to 230.3.195.254230.3.195.2551,022
242230.3.196.0/22230.3.196.1 to 230.3.199.254230.3.199.2551,022
243230.3.200.0/22230.3.200.1 to 230.3.203.254230.3.203.2551,022
244230.3.204.0/22230.3.204.1 to 230.3.207.254230.3.207.2551,022
245230.3.208.0/22230.3.208.1 to 230.3.211.254230.3.211.2551,022
246230.3.212.0/22230.3.212.1 to 230.3.215.254230.3.215.2551,022
247230.3.216.0/22230.3.216.1 to 230.3.219.254230.3.219.2551,022
248230.3.220.0/22230.3.220.1 to 230.3.223.254230.3.223.2551,022
249230.3.224.0/22230.3.224.1 to 230.3.227.254230.3.227.2551,022
250230.3.228.0/22230.3.228.1 to 230.3.231.254230.3.231.2551,022
251230.3.232.0/22230.3.232.1 to 230.3.235.254230.3.235.2551,022
252230.3.236.0/22230.3.236.1 to 230.3.239.254230.3.239.2551,022
253230.3.240.0/22230.3.240.1 to 230.3.243.254230.3.243.2551,022
254230.3.244.0/22230.3.244.1 to 230.3.247.254230.3.247.2551,022
255230.3.248.0/22230.3.248.1 to 230.3.251.254230.3.251.2551,022
256230.3.252.0/22230.3.252.1 to 230.3.255.254230.3.255.2551,022

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.