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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.

Network230.160.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
230.160.0.0
Broadcast address
230.191.255.255
First usable
230.160.0.1
Last usable
230.191.255.254
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 E6A00000 · Integer 3869245440 to 3871342591
Reverse DNS zones
160.230.in-addr.arpa
161.230.in-addr.arpa
162.230.in-addr.arpa
163.230.in-addr.arpa
164.230.in-addr.arpa
165.230.in-addr.arpa
166.230.in-addr.arpa
167.230.in-addr.arpa
168.230.in-addr.arpa
169.230.in-addr.arpa
170.230.in-addr.arpa
171.230.in-addr.arpa
172.230.in-addr.arpa
173.230.in-addr.arpa
174.230.in-addr.arpa
175.230.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
Address11100110.10100000.00000000.00000000230.160.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11100110.10100000.00000000.00000000230.160.0.0
Broadcast11100110.10111111.11111111.11111111230.191.255.255
Split into smaller subnets/23
/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)

230.160.0.0/11 makes 4,096 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1230.160.0.0/23230.160.0.1 to 230.160.1.254230.160.1.255510
2230.160.2.0/23230.160.2.1 to 230.160.3.254230.160.3.255510
3230.160.4.0/23230.160.4.1 to 230.160.5.254230.160.5.255510
4230.160.6.0/23230.160.6.1 to 230.160.7.254230.160.7.255510
5230.160.8.0/23230.160.8.1 to 230.160.9.254230.160.9.255510
6230.160.10.0/23230.160.10.1 to 230.160.11.254230.160.11.255510
7230.160.12.0/23230.160.12.1 to 230.160.13.254230.160.13.255510
8230.160.14.0/23230.160.14.1 to 230.160.15.254230.160.15.255510
9230.160.16.0/23230.160.16.1 to 230.160.17.254230.160.17.255510
10230.160.18.0/23230.160.18.1 to 230.160.19.254230.160.19.255510
11230.160.20.0/23230.160.20.1 to 230.160.21.254230.160.21.255510
12230.160.22.0/23230.160.22.1 to 230.160.23.254230.160.23.255510
13230.160.24.0/23230.160.24.1 to 230.160.25.254230.160.25.255510
14230.160.26.0/23230.160.26.1 to 230.160.27.254230.160.27.255510
15230.160.28.0/23230.160.28.1 to 230.160.29.254230.160.29.255510
16230.160.30.0/23230.160.30.1 to 230.160.31.254230.160.31.255510
17230.160.32.0/23230.160.32.1 to 230.160.33.254230.160.33.255510
18230.160.34.0/23230.160.34.1 to 230.160.35.254230.160.35.255510
19230.160.36.0/23230.160.36.1 to 230.160.37.254230.160.37.255510
20230.160.38.0/23230.160.38.1 to 230.160.39.254230.160.39.255510
21230.160.40.0/23230.160.40.1 to 230.160.41.254230.160.41.255510
22230.160.42.0/23230.160.42.1 to 230.160.43.254230.160.43.255510
23230.160.44.0/23230.160.44.1 to 230.160.45.254230.160.45.255510
24230.160.46.0/23230.160.46.1 to 230.160.47.254230.160.47.255510
25230.160.48.0/23230.160.48.1 to 230.160.49.254230.160.49.255510
26230.160.50.0/23230.160.50.1 to 230.160.51.254230.160.51.255510
27230.160.52.0/23230.160.52.1 to 230.160.53.254230.160.53.255510
28230.160.54.0/23230.160.54.1 to 230.160.55.254230.160.55.255510
29230.160.56.0/23230.160.56.1 to 230.160.57.254230.160.57.255510
30230.160.58.0/23230.160.58.1 to 230.160.59.254230.160.59.255510
31230.160.60.0/23230.160.60.1 to 230.160.61.254230.160.61.255510
32230.160.62.0/23230.160.62.1 to 230.160.63.254230.160.63.255510
33230.160.64.0/23230.160.64.1 to 230.160.65.254230.160.65.255510
34230.160.66.0/23230.160.66.1 to 230.160.67.254230.160.67.255510
35230.160.68.0/23230.160.68.1 to 230.160.69.254230.160.69.255510
36230.160.70.0/23230.160.70.1 to 230.160.71.254230.160.71.255510
37230.160.72.0/23230.160.72.1 to 230.160.73.254230.160.73.255510
38230.160.74.0/23230.160.74.1 to 230.160.75.254230.160.75.255510
39230.160.76.0/23230.160.76.1 to 230.160.77.254230.160.77.255510
40230.160.78.0/23230.160.78.1 to 230.160.79.254230.160.79.255510
41230.160.80.0/23230.160.80.1 to 230.160.81.254230.160.81.255510
42230.160.82.0/23230.160.82.1 to 230.160.83.254230.160.83.255510
43230.160.84.0/23230.160.84.1 to 230.160.85.254230.160.85.255510
44230.160.86.0/23230.160.86.1 to 230.160.87.254230.160.87.255510
45230.160.88.0/23230.160.88.1 to 230.160.89.254230.160.89.255510
46230.160.90.0/23230.160.90.1 to 230.160.91.254230.160.91.255510
47230.160.92.0/23230.160.92.1 to 230.160.93.254230.160.93.255510
48230.160.94.0/23230.160.94.1 to 230.160.95.254230.160.95.255510
49230.160.96.0/23230.160.96.1 to 230.160.97.254230.160.97.255510
50230.160.98.0/23230.160.98.1 to 230.160.99.254230.160.99.255510
51230.160.100.0/23230.160.100.1 to 230.160.101.254230.160.101.255510
52230.160.102.0/23230.160.102.1 to 230.160.103.254230.160.103.255510
53230.160.104.0/23230.160.104.1 to 230.160.105.254230.160.105.255510
54230.160.106.0/23230.160.106.1 to 230.160.107.254230.160.107.255510
55230.160.108.0/23230.160.108.1 to 230.160.109.254230.160.109.255510
56230.160.110.0/23230.160.110.1 to 230.160.111.254230.160.111.255510
57230.160.112.0/23230.160.112.1 to 230.160.113.254230.160.113.255510
58230.160.114.0/23230.160.114.1 to 230.160.115.254230.160.115.255510
59230.160.116.0/23230.160.116.1 to 230.160.117.254230.160.117.255510
60230.160.118.0/23230.160.118.1 to 230.160.119.254230.160.119.255510
61230.160.120.0/23230.160.120.1 to 230.160.121.254230.160.121.255510
62230.160.122.0/23230.160.122.1 to 230.160.123.254230.160.123.255510
63230.160.124.0/23230.160.124.1 to 230.160.125.254230.160.125.255510
64230.160.126.0/23230.160.126.1 to 230.160.127.254230.160.127.255510
65230.160.128.0/23230.160.128.1 to 230.160.129.254230.160.129.255510
66230.160.130.0/23230.160.130.1 to 230.160.131.254230.160.131.255510
67230.160.132.0/23230.160.132.1 to 230.160.133.254230.160.133.255510
68230.160.134.0/23230.160.134.1 to 230.160.135.254230.160.135.255510
69230.160.136.0/23230.160.136.1 to 230.160.137.254230.160.137.255510
70230.160.138.0/23230.160.138.1 to 230.160.139.254230.160.139.255510
71230.160.140.0/23230.160.140.1 to 230.160.141.254230.160.141.255510
72230.160.142.0/23230.160.142.1 to 230.160.143.254230.160.143.255510
73230.160.144.0/23230.160.144.1 to 230.160.145.254230.160.145.255510
74230.160.146.0/23230.160.146.1 to 230.160.147.254230.160.147.255510
75230.160.148.0/23230.160.148.1 to 230.160.149.254230.160.149.255510
76230.160.150.0/23230.160.150.1 to 230.160.151.254230.160.151.255510
77230.160.152.0/23230.160.152.1 to 230.160.153.254230.160.153.255510
78230.160.154.0/23230.160.154.1 to 230.160.155.254230.160.155.255510
79230.160.156.0/23230.160.156.1 to 230.160.157.254230.160.157.255510
80230.160.158.0/23230.160.158.1 to 230.160.159.254230.160.159.255510
81230.160.160.0/23230.160.160.1 to 230.160.161.254230.160.161.255510
82230.160.162.0/23230.160.162.1 to 230.160.163.254230.160.163.255510
83230.160.164.0/23230.160.164.1 to 230.160.165.254230.160.165.255510
84230.160.166.0/23230.160.166.1 to 230.160.167.254230.160.167.255510
85230.160.168.0/23230.160.168.1 to 230.160.169.254230.160.169.255510
86230.160.170.0/23230.160.170.1 to 230.160.171.254230.160.171.255510
87230.160.172.0/23230.160.172.1 to 230.160.173.254230.160.173.255510
88230.160.174.0/23230.160.174.1 to 230.160.175.254230.160.175.255510
89230.160.176.0/23230.160.176.1 to 230.160.177.254230.160.177.255510
90230.160.178.0/23230.160.178.1 to 230.160.179.254230.160.179.255510
91230.160.180.0/23230.160.180.1 to 230.160.181.254230.160.181.255510
92230.160.182.0/23230.160.182.1 to 230.160.183.254230.160.183.255510
93230.160.184.0/23230.160.184.1 to 230.160.185.254230.160.185.255510
94230.160.186.0/23230.160.186.1 to 230.160.187.254230.160.187.255510
95230.160.188.0/23230.160.188.1 to 230.160.189.254230.160.189.255510
96230.160.190.0/23230.160.190.1 to 230.160.191.254230.160.191.255510
97230.160.192.0/23230.160.192.1 to 230.160.193.254230.160.193.255510
98230.160.194.0/23230.160.194.1 to 230.160.195.254230.160.195.255510
99230.160.196.0/23230.160.196.1 to 230.160.197.254230.160.197.255510
100230.160.198.0/23230.160.198.1 to 230.160.199.254230.160.199.255510
101230.160.200.0/23230.160.200.1 to 230.160.201.254230.160.201.255510
102230.160.202.0/23230.160.202.1 to 230.160.203.254230.160.203.255510
103230.160.204.0/23230.160.204.1 to 230.160.205.254230.160.205.255510
104230.160.206.0/23230.160.206.1 to 230.160.207.254230.160.207.255510
105230.160.208.0/23230.160.208.1 to 230.160.209.254230.160.209.255510
106230.160.210.0/23230.160.210.1 to 230.160.211.254230.160.211.255510
107230.160.212.0/23230.160.212.1 to 230.160.213.254230.160.213.255510
108230.160.214.0/23230.160.214.1 to 230.160.215.254230.160.215.255510
109230.160.216.0/23230.160.216.1 to 230.160.217.254230.160.217.255510
110230.160.218.0/23230.160.218.1 to 230.160.219.254230.160.219.255510
111230.160.220.0/23230.160.220.1 to 230.160.221.254230.160.221.255510
112230.160.222.0/23230.160.222.1 to 230.160.223.254230.160.223.255510
113230.160.224.0/23230.160.224.1 to 230.160.225.254230.160.225.255510
114230.160.226.0/23230.160.226.1 to 230.160.227.254230.160.227.255510
115230.160.228.0/23230.160.228.1 to 230.160.229.254230.160.229.255510
116230.160.230.0/23230.160.230.1 to 230.160.231.254230.160.231.255510
117230.160.232.0/23230.160.232.1 to 230.160.233.254230.160.233.255510
118230.160.234.0/23230.160.234.1 to 230.160.235.254230.160.235.255510
119230.160.236.0/23230.160.236.1 to 230.160.237.254230.160.237.255510
120230.160.238.0/23230.160.238.1 to 230.160.239.254230.160.239.255510
121230.160.240.0/23230.160.240.1 to 230.160.241.254230.160.241.255510
122230.160.242.0/23230.160.242.1 to 230.160.243.254230.160.243.255510
123230.160.244.0/23230.160.244.1 to 230.160.245.254230.160.245.255510
124230.160.246.0/23230.160.246.1 to 230.160.247.254230.160.247.255510
125230.160.248.0/23230.160.248.1 to 230.160.249.254230.160.249.255510
126230.160.250.0/23230.160.250.1 to 230.160.251.254230.160.251.255510
127230.160.252.0/23230.160.252.1 to 230.160.253.254230.160.253.255510
128230.160.254.0/23230.160.254.1 to 230.160.255.254230.160.255.255510
129230.161.0.0/23230.161.0.1 to 230.161.1.254230.161.1.255510
130230.161.2.0/23230.161.2.1 to 230.161.3.254230.161.3.255510
131230.161.4.0/23230.161.4.1 to 230.161.5.254230.161.5.255510
132230.161.6.0/23230.161.6.1 to 230.161.7.254230.161.7.255510
133230.161.8.0/23230.161.8.1 to 230.161.9.254230.161.9.255510
134230.161.10.0/23230.161.10.1 to 230.161.11.254230.161.11.255510
135230.161.12.0/23230.161.12.1 to 230.161.13.254230.161.13.255510
136230.161.14.0/23230.161.14.1 to 230.161.15.254230.161.15.255510
137230.161.16.0/23230.161.16.1 to 230.161.17.254230.161.17.255510
138230.161.18.0/23230.161.18.1 to 230.161.19.254230.161.19.255510
139230.161.20.0/23230.161.20.1 to 230.161.21.254230.161.21.255510
140230.161.22.0/23230.161.22.1 to 230.161.23.254230.161.23.255510
141230.161.24.0/23230.161.24.1 to 230.161.25.254230.161.25.255510
142230.161.26.0/23230.161.26.1 to 230.161.27.254230.161.27.255510
143230.161.28.0/23230.161.28.1 to 230.161.29.254230.161.29.255510
144230.161.30.0/23230.161.30.1 to 230.161.31.254230.161.31.255510
145230.161.32.0/23230.161.32.1 to 230.161.33.254230.161.33.255510
146230.161.34.0/23230.161.34.1 to 230.161.35.254230.161.35.255510
147230.161.36.0/23230.161.36.1 to 230.161.37.254230.161.37.255510
148230.161.38.0/23230.161.38.1 to 230.161.39.254230.161.39.255510
149230.161.40.0/23230.161.40.1 to 230.161.41.254230.161.41.255510
150230.161.42.0/23230.161.42.1 to 230.161.43.254230.161.43.255510
151230.161.44.0/23230.161.44.1 to 230.161.45.254230.161.45.255510
152230.161.46.0/23230.161.46.1 to 230.161.47.254230.161.47.255510
153230.161.48.0/23230.161.48.1 to 230.161.49.254230.161.49.255510
154230.161.50.0/23230.161.50.1 to 230.161.51.254230.161.51.255510
155230.161.52.0/23230.161.52.1 to 230.161.53.254230.161.53.255510
156230.161.54.0/23230.161.54.1 to 230.161.55.254230.161.55.255510
157230.161.56.0/23230.161.56.1 to 230.161.57.254230.161.57.255510
158230.161.58.0/23230.161.58.1 to 230.161.59.254230.161.59.255510
159230.161.60.0/23230.161.60.1 to 230.161.61.254230.161.61.255510
160230.161.62.0/23230.161.62.1 to 230.161.63.254230.161.63.255510
161230.161.64.0/23230.161.64.1 to 230.161.65.254230.161.65.255510
162230.161.66.0/23230.161.66.1 to 230.161.67.254230.161.67.255510
163230.161.68.0/23230.161.68.1 to 230.161.69.254230.161.69.255510
164230.161.70.0/23230.161.70.1 to 230.161.71.254230.161.71.255510
165230.161.72.0/23230.161.72.1 to 230.161.73.254230.161.73.255510
166230.161.74.0/23230.161.74.1 to 230.161.75.254230.161.75.255510
167230.161.76.0/23230.161.76.1 to 230.161.77.254230.161.77.255510
168230.161.78.0/23230.161.78.1 to 230.161.79.254230.161.79.255510
169230.161.80.0/23230.161.80.1 to 230.161.81.254230.161.81.255510
170230.161.82.0/23230.161.82.1 to 230.161.83.254230.161.83.255510
171230.161.84.0/23230.161.84.1 to 230.161.85.254230.161.85.255510
172230.161.86.0/23230.161.86.1 to 230.161.87.254230.161.87.255510
173230.161.88.0/23230.161.88.1 to 230.161.89.254230.161.89.255510
174230.161.90.0/23230.161.90.1 to 230.161.91.254230.161.91.255510
175230.161.92.0/23230.161.92.1 to 230.161.93.254230.161.93.255510
176230.161.94.0/23230.161.94.1 to 230.161.95.254230.161.95.255510
177230.161.96.0/23230.161.96.1 to 230.161.97.254230.161.97.255510
178230.161.98.0/23230.161.98.1 to 230.161.99.254230.161.99.255510
179230.161.100.0/23230.161.100.1 to 230.161.101.254230.161.101.255510
180230.161.102.0/23230.161.102.1 to 230.161.103.254230.161.103.255510
181230.161.104.0/23230.161.104.1 to 230.161.105.254230.161.105.255510
182230.161.106.0/23230.161.106.1 to 230.161.107.254230.161.107.255510
183230.161.108.0/23230.161.108.1 to 230.161.109.254230.161.109.255510
184230.161.110.0/23230.161.110.1 to 230.161.111.254230.161.111.255510
185230.161.112.0/23230.161.112.1 to 230.161.113.254230.161.113.255510
186230.161.114.0/23230.161.114.1 to 230.161.115.254230.161.115.255510
187230.161.116.0/23230.161.116.1 to 230.161.117.254230.161.117.255510
188230.161.118.0/23230.161.118.1 to 230.161.119.254230.161.119.255510
189230.161.120.0/23230.161.120.1 to 230.161.121.254230.161.121.255510
190230.161.122.0/23230.161.122.1 to 230.161.123.254230.161.123.255510
191230.161.124.0/23230.161.124.1 to 230.161.125.254230.161.125.255510
192230.161.126.0/23230.161.126.1 to 230.161.127.254230.161.127.255510
193230.161.128.0/23230.161.128.1 to 230.161.129.254230.161.129.255510
194230.161.130.0/23230.161.130.1 to 230.161.131.254230.161.131.255510
195230.161.132.0/23230.161.132.1 to 230.161.133.254230.161.133.255510
196230.161.134.0/23230.161.134.1 to 230.161.135.254230.161.135.255510
197230.161.136.0/23230.161.136.1 to 230.161.137.254230.161.137.255510
198230.161.138.0/23230.161.138.1 to 230.161.139.254230.161.139.255510
199230.161.140.0/23230.161.140.1 to 230.161.141.254230.161.141.255510
200230.161.142.0/23230.161.142.1 to 230.161.143.254230.161.143.255510
201230.161.144.0/23230.161.144.1 to 230.161.145.254230.161.145.255510
202230.161.146.0/23230.161.146.1 to 230.161.147.254230.161.147.255510
203230.161.148.0/23230.161.148.1 to 230.161.149.254230.161.149.255510
204230.161.150.0/23230.161.150.1 to 230.161.151.254230.161.151.255510
205230.161.152.0/23230.161.152.1 to 230.161.153.254230.161.153.255510
206230.161.154.0/23230.161.154.1 to 230.161.155.254230.161.155.255510
207230.161.156.0/23230.161.156.1 to 230.161.157.254230.161.157.255510
208230.161.158.0/23230.161.158.1 to 230.161.159.254230.161.159.255510
209230.161.160.0/23230.161.160.1 to 230.161.161.254230.161.161.255510
210230.161.162.0/23230.161.162.1 to 230.161.163.254230.161.163.255510
211230.161.164.0/23230.161.164.1 to 230.161.165.254230.161.165.255510
212230.161.166.0/23230.161.166.1 to 230.161.167.254230.161.167.255510
213230.161.168.0/23230.161.168.1 to 230.161.169.254230.161.169.255510
214230.161.170.0/23230.161.170.1 to 230.161.171.254230.161.171.255510
215230.161.172.0/23230.161.172.1 to 230.161.173.254230.161.173.255510
216230.161.174.0/23230.161.174.1 to 230.161.175.254230.161.175.255510
217230.161.176.0/23230.161.176.1 to 230.161.177.254230.161.177.255510
218230.161.178.0/23230.161.178.1 to 230.161.179.254230.161.179.255510
219230.161.180.0/23230.161.180.1 to 230.161.181.254230.161.181.255510
220230.161.182.0/23230.161.182.1 to 230.161.183.254230.161.183.255510
221230.161.184.0/23230.161.184.1 to 230.161.185.254230.161.185.255510
222230.161.186.0/23230.161.186.1 to 230.161.187.254230.161.187.255510
223230.161.188.0/23230.161.188.1 to 230.161.189.254230.161.189.255510
224230.161.190.0/23230.161.190.1 to 230.161.191.254230.161.191.255510
225230.161.192.0/23230.161.192.1 to 230.161.193.254230.161.193.255510
226230.161.194.0/23230.161.194.1 to 230.161.195.254230.161.195.255510
227230.161.196.0/23230.161.196.1 to 230.161.197.254230.161.197.255510
228230.161.198.0/23230.161.198.1 to 230.161.199.254230.161.199.255510
229230.161.200.0/23230.161.200.1 to 230.161.201.254230.161.201.255510
230230.161.202.0/23230.161.202.1 to 230.161.203.254230.161.203.255510
231230.161.204.0/23230.161.204.1 to 230.161.205.254230.161.205.255510
232230.161.206.0/23230.161.206.1 to 230.161.207.254230.161.207.255510
233230.161.208.0/23230.161.208.1 to 230.161.209.254230.161.209.255510
234230.161.210.0/23230.161.210.1 to 230.161.211.254230.161.211.255510
235230.161.212.0/23230.161.212.1 to 230.161.213.254230.161.213.255510
236230.161.214.0/23230.161.214.1 to 230.161.215.254230.161.215.255510
237230.161.216.0/23230.161.216.1 to 230.161.217.254230.161.217.255510
238230.161.218.0/23230.161.218.1 to 230.161.219.254230.161.219.255510
239230.161.220.0/23230.161.220.1 to 230.161.221.254230.161.221.255510
240230.161.222.0/23230.161.222.1 to 230.161.223.254230.161.223.255510
241230.161.224.0/23230.161.224.1 to 230.161.225.254230.161.225.255510
242230.161.226.0/23230.161.226.1 to 230.161.227.254230.161.227.255510
243230.161.228.0/23230.161.228.1 to 230.161.229.254230.161.229.255510
244230.161.230.0/23230.161.230.1 to 230.161.231.254230.161.231.255510
245230.161.232.0/23230.161.232.1 to 230.161.233.254230.161.233.255510
246230.161.234.0/23230.161.234.1 to 230.161.235.254230.161.235.255510
247230.161.236.0/23230.161.236.1 to 230.161.237.254230.161.237.255510
248230.161.238.0/23230.161.238.1 to 230.161.239.254230.161.239.255510
249230.161.240.0/23230.161.240.1 to 230.161.241.254230.161.241.255510
250230.161.242.0/23230.161.242.1 to 230.161.243.254230.161.243.255510
251230.161.244.0/23230.161.244.1 to 230.161.245.254230.161.245.255510
252230.161.246.0/23230.161.246.1 to 230.161.247.254230.161.247.255510
253230.161.248.0/23230.161.248.1 to 230.161.249.254230.161.249.255510
254230.161.250.0/23230.161.250.1 to 230.161.251.254230.161.251.255510
255230.161.252.0/23230.161.252.1 to 230.161.253.254230.161.253.255510
256230.161.254.0/23230.161.254.1 to 230.161.255.254230.161.255.255510

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.