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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.

Network112.72.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
112.72.0.0
Broadcast address
112.75.255.255
First usable
112.72.0.1
Last usable
112.75.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 70480000 · Integer 1883766784 to 1884028927
Reverse DNS zones
72.112.in-addr.arpa
73.112.in-addr.arpa
74.112.in-addr.arpa
75.112.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110000.01001000.00000000.00000000112.72.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01110000.01001000.00000000.00000000112.72.0.0
Broadcast01110000.01001011.11111111.11111111112.75.255.255
Split into smaller subnets/23

112.72.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1112.72.0.0/23112.72.0.1 to 112.72.1.254112.72.1.255510
2112.72.2.0/23112.72.2.1 to 112.72.3.254112.72.3.255510
3112.72.4.0/23112.72.4.1 to 112.72.5.254112.72.5.255510
4112.72.6.0/23112.72.6.1 to 112.72.7.254112.72.7.255510
5112.72.8.0/23112.72.8.1 to 112.72.9.254112.72.9.255510
6112.72.10.0/23112.72.10.1 to 112.72.11.254112.72.11.255510
7112.72.12.0/23112.72.12.1 to 112.72.13.254112.72.13.255510
8112.72.14.0/23112.72.14.1 to 112.72.15.254112.72.15.255510
9112.72.16.0/23112.72.16.1 to 112.72.17.254112.72.17.255510
10112.72.18.0/23112.72.18.1 to 112.72.19.254112.72.19.255510
11112.72.20.0/23112.72.20.1 to 112.72.21.254112.72.21.255510
12112.72.22.0/23112.72.22.1 to 112.72.23.254112.72.23.255510
13112.72.24.0/23112.72.24.1 to 112.72.25.254112.72.25.255510
14112.72.26.0/23112.72.26.1 to 112.72.27.254112.72.27.255510
15112.72.28.0/23112.72.28.1 to 112.72.29.254112.72.29.255510
16112.72.30.0/23112.72.30.1 to 112.72.31.254112.72.31.255510
17112.72.32.0/23112.72.32.1 to 112.72.33.254112.72.33.255510
18112.72.34.0/23112.72.34.1 to 112.72.35.254112.72.35.255510
19112.72.36.0/23112.72.36.1 to 112.72.37.254112.72.37.255510
20112.72.38.0/23112.72.38.1 to 112.72.39.254112.72.39.255510
21112.72.40.0/23112.72.40.1 to 112.72.41.254112.72.41.255510
22112.72.42.0/23112.72.42.1 to 112.72.43.254112.72.43.255510
23112.72.44.0/23112.72.44.1 to 112.72.45.254112.72.45.255510
24112.72.46.0/23112.72.46.1 to 112.72.47.254112.72.47.255510
25112.72.48.0/23112.72.48.1 to 112.72.49.254112.72.49.255510
26112.72.50.0/23112.72.50.1 to 112.72.51.254112.72.51.255510
27112.72.52.0/23112.72.52.1 to 112.72.53.254112.72.53.255510
28112.72.54.0/23112.72.54.1 to 112.72.55.254112.72.55.255510
29112.72.56.0/23112.72.56.1 to 112.72.57.254112.72.57.255510
30112.72.58.0/23112.72.58.1 to 112.72.59.254112.72.59.255510
31112.72.60.0/23112.72.60.1 to 112.72.61.254112.72.61.255510
32112.72.62.0/23112.72.62.1 to 112.72.63.254112.72.63.255510
33112.72.64.0/23112.72.64.1 to 112.72.65.254112.72.65.255510
34112.72.66.0/23112.72.66.1 to 112.72.67.254112.72.67.255510
35112.72.68.0/23112.72.68.1 to 112.72.69.254112.72.69.255510
36112.72.70.0/23112.72.70.1 to 112.72.71.254112.72.71.255510
37112.72.72.0/23112.72.72.1 to 112.72.73.254112.72.73.255510
38112.72.74.0/23112.72.74.1 to 112.72.75.254112.72.75.255510
39112.72.76.0/23112.72.76.1 to 112.72.77.254112.72.77.255510
40112.72.78.0/23112.72.78.1 to 112.72.79.254112.72.79.255510
41112.72.80.0/23112.72.80.1 to 112.72.81.254112.72.81.255510
42112.72.82.0/23112.72.82.1 to 112.72.83.254112.72.83.255510
43112.72.84.0/23112.72.84.1 to 112.72.85.254112.72.85.255510
44112.72.86.0/23112.72.86.1 to 112.72.87.254112.72.87.255510
45112.72.88.0/23112.72.88.1 to 112.72.89.254112.72.89.255510
46112.72.90.0/23112.72.90.1 to 112.72.91.254112.72.91.255510
47112.72.92.0/23112.72.92.1 to 112.72.93.254112.72.93.255510
48112.72.94.0/23112.72.94.1 to 112.72.95.254112.72.95.255510
49112.72.96.0/23112.72.96.1 to 112.72.97.254112.72.97.255510
50112.72.98.0/23112.72.98.1 to 112.72.99.254112.72.99.255510
51112.72.100.0/23112.72.100.1 to 112.72.101.254112.72.101.255510
52112.72.102.0/23112.72.102.1 to 112.72.103.254112.72.103.255510
53112.72.104.0/23112.72.104.1 to 112.72.105.254112.72.105.255510
54112.72.106.0/23112.72.106.1 to 112.72.107.254112.72.107.255510
55112.72.108.0/23112.72.108.1 to 112.72.109.254112.72.109.255510
56112.72.110.0/23112.72.110.1 to 112.72.111.254112.72.111.255510
57112.72.112.0/23112.72.112.1 to 112.72.113.254112.72.113.255510
58112.72.114.0/23112.72.114.1 to 112.72.115.254112.72.115.255510
59112.72.116.0/23112.72.116.1 to 112.72.117.254112.72.117.255510
60112.72.118.0/23112.72.118.1 to 112.72.119.254112.72.119.255510
61112.72.120.0/23112.72.120.1 to 112.72.121.254112.72.121.255510
62112.72.122.0/23112.72.122.1 to 112.72.123.254112.72.123.255510
63112.72.124.0/23112.72.124.1 to 112.72.125.254112.72.125.255510
64112.72.126.0/23112.72.126.1 to 112.72.127.254112.72.127.255510
65112.72.128.0/23112.72.128.1 to 112.72.129.254112.72.129.255510
66112.72.130.0/23112.72.130.1 to 112.72.131.254112.72.131.255510
67112.72.132.0/23112.72.132.1 to 112.72.133.254112.72.133.255510
68112.72.134.0/23112.72.134.1 to 112.72.135.254112.72.135.255510
69112.72.136.0/23112.72.136.1 to 112.72.137.254112.72.137.255510
70112.72.138.0/23112.72.138.1 to 112.72.139.254112.72.139.255510
71112.72.140.0/23112.72.140.1 to 112.72.141.254112.72.141.255510
72112.72.142.0/23112.72.142.1 to 112.72.143.254112.72.143.255510
73112.72.144.0/23112.72.144.1 to 112.72.145.254112.72.145.255510
74112.72.146.0/23112.72.146.1 to 112.72.147.254112.72.147.255510
75112.72.148.0/23112.72.148.1 to 112.72.149.254112.72.149.255510
76112.72.150.0/23112.72.150.1 to 112.72.151.254112.72.151.255510
77112.72.152.0/23112.72.152.1 to 112.72.153.254112.72.153.255510
78112.72.154.0/23112.72.154.1 to 112.72.155.254112.72.155.255510
79112.72.156.0/23112.72.156.1 to 112.72.157.254112.72.157.255510
80112.72.158.0/23112.72.158.1 to 112.72.159.254112.72.159.255510
81112.72.160.0/23112.72.160.1 to 112.72.161.254112.72.161.255510
82112.72.162.0/23112.72.162.1 to 112.72.163.254112.72.163.255510
83112.72.164.0/23112.72.164.1 to 112.72.165.254112.72.165.255510
84112.72.166.0/23112.72.166.1 to 112.72.167.254112.72.167.255510
85112.72.168.0/23112.72.168.1 to 112.72.169.254112.72.169.255510
86112.72.170.0/23112.72.170.1 to 112.72.171.254112.72.171.255510
87112.72.172.0/23112.72.172.1 to 112.72.173.254112.72.173.255510
88112.72.174.0/23112.72.174.1 to 112.72.175.254112.72.175.255510
89112.72.176.0/23112.72.176.1 to 112.72.177.254112.72.177.255510
90112.72.178.0/23112.72.178.1 to 112.72.179.254112.72.179.255510
91112.72.180.0/23112.72.180.1 to 112.72.181.254112.72.181.255510
92112.72.182.0/23112.72.182.1 to 112.72.183.254112.72.183.255510
93112.72.184.0/23112.72.184.1 to 112.72.185.254112.72.185.255510
94112.72.186.0/23112.72.186.1 to 112.72.187.254112.72.187.255510
95112.72.188.0/23112.72.188.1 to 112.72.189.254112.72.189.255510
96112.72.190.0/23112.72.190.1 to 112.72.191.254112.72.191.255510
97112.72.192.0/23112.72.192.1 to 112.72.193.254112.72.193.255510
98112.72.194.0/23112.72.194.1 to 112.72.195.254112.72.195.255510
99112.72.196.0/23112.72.196.1 to 112.72.197.254112.72.197.255510
100112.72.198.0/23112.72.198.1 to 112.72.199.254112.72.199.255510
101112.72.200.0/23112.72.200.1 to 112.72.201.254112.72.201.255510
102112.72.202.0/23112.72.202.1 to 112.72.203.254112.72.203.255510
103112.72.204.0/23112.72.204.1 to 112.72.205.254112.72.205.255510
104112.72.206.0/23112.72.206.1 to 112.72.207.254112.72.207.255510
105112.72.208.0/23112.72.208.1 to 112.72.209.254112.72.209.255510
106112.72.210.0/23112.72.210.1 to 112.72.211.254112.72.211.255510
107112.72.212.0/23112.72.212.1 to 112.72.213.254112.72.213.255510
108112.72.214.0/23112.72.214.1 to 112.72.215.254112.72.215.255510
109112.72.216.0/23112.72.216.1 to 112.72.217.254112.72.217.255510
110112.72.218.0/23112.72.218.1 to 112.72.219.254112.72.219.255510
111112.72.220.0/23112.72.220.1 to 112.72.221.254112.72.221.255510
112112.72.222.0/23112.72.222.1 to 112.72.223.254112.72.223.255510
113112.72.224.0/23112.72.224.1 to 112.72.225.254112.72.225.255510
114112.72.226.0/23112.72.226.1 to 112.72.227.254112.72.227.255510
115112.72.228.0/23112.72.228.1 to 112.72.229.254112.72.229.255510
116112.72.230.0/23112.72.230.1 to 112.72.231.254112.72.231.255510
117112.72.232.0/23112.72.232.1 to 112.72.233.254112.72.233.255510
118112.72.234.0/23112.72.234.1 to 112.72.235.254112.72.235.255510
119112.72.236.0/23112.72.236.1 to 112.72.237.254112.72.237.255510
120112.72.238.0/23112.72.238.1 to 112.72.239.254112.72.239.255510
121112.72.240.0/23112.72.240.1 to 112.72.241.254112.72.241.255510
122112.72.242.0/23112.72.242.1 to 112.72.243.254112.72.243.255510
123112.72.244.0/23112.72.244.1 to 112.72.245.254112.72.245.255510
124112.72.246.0/23112.72.246.1 to 112.72.247.254112.72.247.255510
125112.72.248.0/23112.72.248.1 to 112.72.249.254112.72.249.255510
126112.72.250.0/23112.72.250.1 to 112.72.251.254112.72.251.255510
127112.72.252.0/23112.72.252.1 to 112.72.253.254112.72.253.255510
128112.72.254.0/23112.72.254.1 to 112.72.255.254112.72.255.255510
129112.73.0.0/23112.73.0.1 to 112.73.1.254112.73.1.255510
130112.73.2.0/23112.73.2.1 to 112.73.3.254112.73.3.255510
131112.73.4.0/23112.73.4.1 to 112.73.5.254112.73.5.255510
132112.73.6.0/23112.73.6.1 to 112.73.7.254112.73.7.255510
133112.73.8.0/23112.73.8.1 to 112.73.9.254112.73.9.255510
134112.73.10.0/23112.73.10.1 to 112.73.11.254112.73.11.255510
135112.73.12.0/23112.73.12.1 to 112.73.13.254112.73.13.255510
136112.73.14.0/23112.73.14.1 to 112.73.15.254112.73.15.255510
137112.73.16.0/23112.73.16.1 to 112.73.17.254112.73.17.255510
138112.73.18.0/23112.73.18.1 to 112.73.19.254112.73.19.255510
139112.73.20.0/23112.73.20.1 to 112.73.21.254112.73.21.255510
140112.73.22.0/23112.73.22.1 to 112.73.23.254112.73.23.255510
141112.73.24.0/23112.73.24.1 to 112.73.25.254112.73.25.255510
142112.73.26.0/23112.73.26.1 to 112.73.27.254112.73.27.255510
143112.73.28.0/23112.73.28.1 to 112.73.29.254112.73.29.255510
144112.73.30.0/23112.73.30.1 to 112.73.31.254112.73.31.255510
145112.73.32.0/23112.73.32.1 to 112.73.33.254112.73.33.255510
146112.73.34.0/23112.73.34.1 to 112.73.35.254112.73.35.255510
147112.73.36.0/23112.73.36.1 to 112.73.37.254112.73.37.255510
148112.73.38.0/23112.73.38.1 to 112.73.39.254112.73.39.255510
149112.73.40.0/23112.73.40.1 to 112.73.41.254112.73.41.255510
150112.73.42.0/23112.73.42.1 to 112.73.43.254112.73.43.255510
151112.73.44.0/23112.73.44.1 to 112.73.45.254112.73.45.255510
152112.73.46.0/23112.73.46.1 to 112.73.47.254112.73.47.255510
153112.73.48.0/23112.73.48.1 to 112.73.49.254112.73.49.255510
154112.73.50.0/23112.73.50.1 to 112.73.51.254112.73.51.255510
155112.73.52.0/23112.73.52.1 to 112.73.53.254112.73.53.255510
156112.73.54.0/23112.73.54.1 to 112.73.55.254112.73.55.255510
157112.73.56.0/23112.73.56.1 to 112.73.57.254112.73.57.255510
158112.73.58.0/23112.73.58.1 to 112.73.59.254112.73.59.255510
159112.73.60.0/23112.73.60.1 to 112.73.61.254112.73.61.255510
160112.73.62.0/23112.73.62.1 to 112.73.63.254112.73.63.255510
161112.73.64.0/23112.73.64.1 to 112.73.65.254112.73.65.255510
162112.73.66.0/23112.73.66.1 to 112.73.67.254112.73.67.255510
163112.73.68.0/23112.73.68.1 to 112.73.69.254112.73.69.255510
164112.73.70.0/23112.73.70.1 to 112.73.71.254112.73.71.255510
165112.73.72.0/23112.73.72.1 to 112.73.73.254112.73.73.255510
166112.73.74.0/23112.73.74.1 to 112.73.75.254112.73.75.255510
167112.73.76.0/23112.73.76.1 to 112.73.77.254112.73.77.255510
168112.73.78.0/23112.73.78.1 to 112.73.79.254112.73.79.255510
169112.73.80.0/23112.73.80.1 to 112.73.81.254112.73.81.255510
170112.73.82.0/23112.73.82.1 to 112.73.83.254112.73.83.255510
171112.73.84.0/23112.73.84.1 to 112.73.85.254112.73.85.255510
172112.73.86.0/23112.73.86.1 to 112.73.87.254112.73.87.255510
173112.73.88.0/23112.73.88.1 to 112.73.89.254112.73.89.255510
174112.73.90.0/23112.73.90.1 to 112.73.91.254112.73.91.255510
175112.73.92.0/23112.73.92.1 to 112.73.93.254112.73.93.255510
176112.73.94.0/23112.73.94.1 to 112.73.95.254112.73.95.255510
177112.73.96.0/23112.73.96.1 to 112.73.97.254112.73.97.255510
178112.73.98.0/23112.73.98.1 to 112.73.99.254112.73.99.255510
179112.73.100.0/23112.73.100.1 to 112.73.101.254112.73.101.255510
180112.73.102.0/23112.73.102.1 to 112.73.103.254112.73.103.255510
181112.73.104.0/23112.73.104.1 to 112.73.105.254112.73.105.255510
182112.73.106.0/23112.73.106.1 to 112.73.107.254112.73.107.255510
183112.73.108.0/23112.73.108.1 to 112.73.109.254112.73.109.255510
184112.73.110.0/23112.73.110.1 to 112.73.111.254112.73.111.255510
185112.73.112.0/23112.73.112.1 to 112.73.113.254112.73.113.255510
186112.73.114.0/23112.73.114.1 to 112.73.115.254112.73.115.255510
187112.73.116.0/23112.73.116.1 to 112.73.117.254112.73.117.255510
188112.73.118.0/23112.73.118.1 to 112.73.119.254112.73.119.255510
189112.73.120.0/23112.73.120.1 to 112.73.121.254112.73.121.255510
190112.73.122.0/23112.73.122.1 to 112.73.123.254112.73.123.255510
191112.73.124.0/23112.73.124.1 to 112.73.125.254112.73.125.255510
192112.73.126.0/23112.73.126.1 to 112.73.127.254112.73.127.255510
193112.73.128.0/23112.73.128.1 to 112.73.129.254112.73.129.255510
194112.73.130.0/23112.73.130.1 to 112.73.131.254112.73.131.255510
195112.73.132.0/23112.73.132.1 to 112.73.133.254112.73.133.255510
196112.73.134.0/23112.73.134.1 to 112.73.135.254112.73.135.255510
197112.73.136.0/23112.73.136.1 to 112.73.137.254112.73.137.255510
198112.73.138.0/23112.73.138.1 to 112.73.139.254112.73.139.255510
199112.73.140.0/23112.73.140.1 to 112.73.141.254112.73.141.255510
200112.73.142.0/23112.73.142.1 to 112.73.143.254112.73.143.255510
201112.73.144.0/23112.73.144.1 to 112.73.145.254112.73.145.255510
202112.73.146.0/23112.73.146.1 to 112.73.147.254112.73.147.255510
203112.73.148.0/23112.73.148.1 to 112.73.149.254112.73.149.255510
204112.73.150.0/23112.73.150.1 to 112.73.151.254112.73.151.255510
205112.73.152.0/23112.73.152.1 to 112.73.153.254112.73.153.255510
206112.73.154.0/23112.73.154.1 to 112.73.155.254112.73.155.255510
207112.73.156.0/23112.73.156.1 to 112.73.157.254112.73.157.255510
208112.73.158.0/23112.73.158.1 to 112.73.159.254112.73.159.255510
209112.73.160.0/23112.73.160.1 to 112.73.161.254112.73.161.255510
210112.73.162.0/23112.73.162.1 to 112.73.163.254112.73.163.255510
211112.73.164.0/23112.73.164.1 to 112.73.165.254112.73.165.255510
212112.73.166.0/23112.73.166.1 to 112.73.167.254112.73.167.255510
213112.73.168.0/23112.73.168.1 to 112.73.169.254112.73.169.255510
214112.73.170.0/23112.73.170.1 to 112.73.171.254112.73.171.255510
215112.73.172.0/23112.73.172.1 to 112.73.173.254112.73.173.255510
216112.73.174.0/23112.73.174.1 to 112.73.175.254112.73.175.255510
217112.73.176.0/23112.73.176.1 to 112.73.177.254112.73.177.255510
218112.73.178.0/23112.73.178.1 to 112.73.179.254112.73.179.255510
219112.73.180.0/23112.73.180.1 to 112.73.181.254112.73.181.255510
220112.73.182.0/23112.73.182.1 to 112.73.183.254112.73.183.255510
221112.73.184.0/23112.73.184.1 to 112.73.185.254112.73.185.255510
222112.73.186.0/23112.73.186.1 to 112.73.187.254112.73.187.255510
223112.73.188.0/23112.73.188.1 to 112.73.189.254112.73.189.255510
224112.73.190.0/23112.73.190.1 to 112.73.191.254112.73.191.255510
225112.73.192.0/23112.73.192.1 to 112.73.193.254112.73.193.255510
226112.73.194.0/23112.73.194.1 to 112.73.195.254112.73.195.255510
227112.73.196.0/23112.73.196.1 to 112.73.197.254112.73.197.255510
228112.73.198.0/23112.73.198.1 to 112.73.199.254112.73.199.255510
229112.73.200.0/23112.73.200.1 to 112.73.201.254112.73.201.255510
230112.73.202.0/23112.73.202.1 to 112.73.203.254112.73.203.255510
231112.73.204.0/23112.73.204.1 to 112.73.205.254112.73.205.255510
232112.73.206.0/23112.73.206.1 to 112.73.207.254112.73.207.255510
233112.73.208.0/23112.73.208.1 to 112.73.209.254112.73.209.255510
234112.73.210.0/23112.73.210.1 to 112.73.211.254112.73.211.255510
235112.73.212.0/23112.73.212.1 to 112.73.213.254112.73.213.255510
236112.73.214.0/23112.73.214.1 to 112.73.215.254112.73.215.255510
237112.73.216.0/23112.73.216.1 to 112.73.217.254112.73.217.255510
238112.73.218.0/23112.73.218.1 to 112.73.219.254112.73.219.255510
239112.73.220.0/23112.73.220.1 to 112.73.221.254112.73.221.255510
240112.73.222.0/23112.73.222.1 to 112.73.223.254112.73.223.255510
241112.73.224.0/23112.73.224.1 to 112.73.225.254112.73.225.255510
242112.73.226.0/23112.73.226.1 to 112.73.227.254112.73.227.255510
243112.73.228.0/23112.73.228.1 to 112.73.229.254112.73.229.255510
244112.73.230.0/23112.73.230.1 to 112.73.231.254112.73.231.255510
245112.73.232.0/23112.73.232.1 to 112.73.233.254112.73.233.255510
246112.73.234.0/23112.73.234.1 to 112.73.235.254112.73.235.255510
247112.73.236.0/23112.73.236.1 to 112.73.237.254112.73.237.255510
248112.73.238.0/23112.73.238.1 to 112.73.239.254112.73.239.255510
249112.73.240.0/23112.73.240.1 to 112.73.241.254112.73.241.255510
250112.73.242.0/23112.73.242.1 to 112.73.243.254112.73.243.255510
251112.73.244.0/23112.73.244.1 to 112.73.245.254112.73.245.255510
252112.73.246.0/23112.73.246.1 to 112.73.247.254112.73.247.255510
253112.73.248.0/23112.73.248.1 to 112.73.249.254112.73.249.255510
254112.73.250.0/23112.73.250.1 to 112.73.251.254112.73.251.255510
255112.73.252.0/23112.73.252.1 to 112.73.253.254112.73.253.255510
256112.73.254.0/23112.73.254.1 to 112.73.255.254112.73.255.255510

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