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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.

Network152.9.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
152.9.0.0
Broadcast address
152.9.255.255
First usable
152.9.0.1
Last usable
152.9.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
B (default /16)
As numbers
Hex 98090000 · Integer 2550726656 to 2550792191
Reverse DNS zone
9.152.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011000.00001001..00000000.00000000152.9.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network10011000.00001001..00000000.00000000152.9.0.0
Broadcast10011000.00001001..11111111.11111111152.9.255.255
Split into smaller subnets/24

152.9.0.0/16 makes 256 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1152.9.0.0/24152.9.0.1 to 152.9.0.254152.9.0.255254
2152.9.1.0/24152.9.1.1 to 152.9.1.254152.9.1.255254
3152.9.2.0/24152.9.2.1 to 152.9.2.254152.9.2.255254
4152.9.3.0/24152.9.3.1 to 152.9.3.254152.9.3.255254
5152.9.4.0/24152.9.4.1 to 152.9.4.254152.9.4.255254
6152.9.5.0/24152.9.5.1 to 152.9.5.254152.9.5.255254
7152.9.6.0/24152.9.6.1 to 152.9.6.254152.9.6.255254
8152.9.7.0/24152.9.7.1 to 152.9.7.254152.9.7.255254
9152.9.8.0/24152.9.8.1 to 152.9.8.254152.9.8.255254
10152.9.9.0/24152.9.9.1 to 152.9.9.254152.9.9.255254
11152.9.10.0/24152.9.10.1 to 152.9.10.254152.9.10.255254
12152.9.11.0/24152.9.11.1 to 152.9.11.254152.9.11.255254
13152.9.12.0/24152.9.12.1 to 152.9.12.254152.9.12.255254
14152.9.13.0/24152.9.13.1 to 152.9.13.254152.9.13.255254
15152.9.14.0/24152.9.14.1 to 152.9.14.254152.9.14.255254
16152.9.15.0/24152.9.15.1 to 152.9.15.254152.9.15.255254
17152.9.16.0/24152.9.16.1 to 152.9.16.254152.9.16.255254
18152.9.17.0/24152.9.17.1 to 152.9.17.254152.9.17.255254
19152.9.18.0/24152.9.18.1 to 152.9.18.254152.9.18.255254
20152.9.19.0/24152.9.19.1 to 152.9.19.254152.9.19.255254
21152.9.20.0/24152.9.20.1 to 152.9.20.254152.9.20.255254
22152.9.21.0/24152.9.21.1 to 152.9.21.254152.9.21.255254
23152.9.22.0/24152.9.22.1 to 152.9.22.254152.9.22.255254
24152.9.23.0/24152.9.23.1 to 152.9.23.254152.9.23.255254
25152.9.24.0/24152.9.24.1 to 152.9.24.254152.9.24.255254
26152.9.25.0/24152.9.25.1 to 152.9.25.254152.9.25.255254
27152.9.26.0/24152.9.26.1 to 152.9.26.254152.9.26.255254
28152.9.27.0/24152.9.27.1 to 152.9.27.254152.9.27.255254
29152.9.28.0/24152.9.28.1 to 152.9.28.254152.9.28.255254
30152.9.29.0/24152.9.29.1 to 152.9.29.254152.9.29.255254
31152.9.30.0/24152.9.30.1 to 152.9.30.254152.9.30.255254
32152.9.31.0/24152.9.31.1 to 152.9.31.254152.9.31.255254
33152.9.32.0/24152.9.32.1 to 152.9.32.254152.9.32.255254
34152.9.33.0/24152.9.33.1 to 152.9.33.254152.9.33.255254
35152.9.34.0/24152.9.34.1 to 152.9.34.254152.9.34.255254
36152.9.35.0/24152.9.35.1 to 152.9.35.254152.9.35.255254
37152.9.36.0/24152.9.36.1 to 152.9.36.254152.9.36.255254
38152.9.37.0/24152.9.37.1 to 152.9.37.254152.9.37.255254
39152.9.38.0/24152.9.38.1 to 152.9.38.254152.9.38.255254
40152.9.39.0/24152.9.39.1 to 152.9.39.254152.9.39.255254
41152.9.40.0/24152.9.40.1 to 152.9.40.254152.9.40.255254
42152.9.41.0/24152.9.41.1 to 152.9.41.254152.9.41.255254
43152.9.42.0/24152.9.42.1 to 152.9.42.254152.9.42.255254
44152.9.43.0/24152.9.43.1 to 152.9.43.254152.9.43.255254
45152.9.44.0/24152.9.44.1 to 152.9.44.254152.9.44.255254
46152.9.45.0/24152.9.45.1 to 152.9.45.254152.9.45.255254
47152.9.46.0/24152.9.46.1 to 152.9.46.254152.9.46.255254
48152.9.47.0/24152.9.47.1 to 152.9.47.254152.9.47.255254
49152.9.48.0/24152.9.48.1 to 152.9.48.254152.9.48.255254
50152.9.49.0/24152.9.49.1 to 152.9.49.254152.9.49.255254
51152.9.50.0/24152.9.50.1 to 152.9.50.254152.9.50.255254
52152.9.51.0/24152.9.51.1 to 152.9.51.254152.9.51.255254
53152.9.52.0/24152.9.52.1 to 152.9.52.254152.9.52.255254
54152.9.53.0/24152.9.53.1 to 152.9.53.254152.9.53.255254
55152.9.54.0/24152.9.54.1 to 152.9.54.254152.9.54.255254
56152.9.55.0/24152.9.55.1 to 152.9.55.254152.9.55.255254
57152.9.56.0/24152.9.56.1 to 152.9.56.254152.9.56.255254
58152.9.57.0/24152.9.57.1 to 152.9.57.254152.9.57.255254
59152.9.58.0/24152.9.58.1 to 152.9.58.254152.9.58.255254
60152.9.59.0/24152.9.59.1 to 152.9.59.254152.9.59.255254
61152.9.60.0/24152.9.60.1 to 152.9.60.254152.9.60.255254
62152.9.61.0/24152.9.61.1 to 152.9.61.254152.9.61.255254
63152.9.62.0/24152.9.62.1 to 152.9.62.254152.9.62.255254
64152.9.63.0/24152.9.63.1 to 152.9.63.254152.9.63.255254
65152.9.64.0/24152.9.64.1 to 152.9.64.254152.9.64.255254
66152.9.65.0/24152.9.65.1 to 152.9.65.254152.9.65.255254
67152.9.66.0/24152.9.66.1 to 152.9.66.254152.9.66.255254
68152.9.67.0/24152.9.67.1 to 152.9.67.254152.9.67.255254
69152.9.68.0/24152.9.68.1 to 152.9.68.254152.9.68.255254
70152.9.69.0/24152.9.69.1 to 152.9.69.254152.9.69.255254
71152.9.70.0/24152.9.70.1 to 152.9.70.254152.9.70.255254
72152.9.71.0/24152.9.71.1 to 152.9.71.254152.9.71.255254
73152.9.72.0/24152.9.72.1 to 152.9.72.254152.9.72.255254
74152.9.73.0/24152.9.73.1 to 152.9.73.254152.9.73.255254
75152.9.74.0/24152.9.74.1 to 152.9.74.254152.9.74.255254
76152.9.75.0/24152.9.75.1 to 152.9.75.254152.9.75.255254
77152.9.76.0/24152.9.76.1 to 152.9.76.254152.9.76.255254
78152.9.77.0/24152.9.77.1 to 152.9.77.254152.9.77.255254
79152.9.78.0/24152.9.78.1 to 152.9.78.254152.9.78.255254
80152.9.79.0/24152.9.79.1 to 152.9.79.254152.9.79.255254
81152.9.80.0/24152.9.80.1 to 152.9.80.254152.9.80.255254
82152.9.81.0/24152.9.81.1 to 152.9.81.254152.9.81.255254
83152.9.82.0/24152.9.82.1 to 152.9.82.254152.9.82.255254
84152.9.83.0/24152.9.83.1 to 152.9.83.254152.9.83.255254
85152.9.84.0/24152.9.84.1 to 152.9.84.254152.9.84.255254
86152.9.85.0/24152.9.85.1 to 152.9.85.254152.9.85.255254
87152.9.86.0/24152.9.86.1 to 152.9.86.254152.9.86.255254
88152.9.87.0/24152.9.87.1 to 152.9.87.254152.9.87.255254
89152.9.88.0/24152.9.88.1 to 152.9.88.254152.9.88.255254
90152.9.89.0/24152.9.89.1 to 152.9.89.254152.9.89.255254
91152.9.90.0/24152.9.90.1 to 152.9.90.254152.9.90.255254
92152.9.91.0/24152.9.91.1 to 152.9.91.254152.9.91.255254
93152.9.92.0/24152.9.92.1 to 152.9.92.254152.9.92.255254
94152.9.93.0/24152.9.93.1 to 152.9.93.254152.9.93.255254
95152.9.94.0/24152.9.94.1 to 152.9.94.254152.9.94.255254
96152.9.95.0/24152.9.95.1 to 152.9.95.254152.9.95.255254
97152.9.96.0/24152.9.96.1 to 152.9.96.254152.9.96.255254
98152.9.97.0/24152.9.97.1 to 152.9.97.254152.9.97.255254
99152.9.98.0/24152.9.98.1 to 152.9.98.254152.9.98.255254
100152.9.99.0/24152.9.99.1 to 152.9.99.254152.9.99.255254
101152.9.100.0/24152.9.100.1 to 152.9.100.254152.9.100.255254
102152.9.101.0/24152.9.101.1 to 152.9.101.254152.9.101.255254
103152.9.102.0/24152.9.102.1 to 152.9.102.254152.9.102.255254
104152.9.103.0/24152.9.103.1 to 152.9.103.254152.9.103.255254
105152.9.104.0/24152.9.104.1 to 152.9.104.254152.9.104.255254
106152.9.105.0/24152.9.105.1 to 152.9.105.254152.9.105.255254
107152.9.106.0/24152.9.106.1 to 152.9.106.254152.9.106.255254
108152.9.107.0/24152.9.107.1 to 152.9.107.254152.9.107.255254
109152.9.108.0/24152.9.108.1 to 152.9.108.254152.9.108.255254
110152.9.109.0/24152.9.109.1 to 152.9.109.254152.9.109.255254
111152.9.110.0/24152.9.110.1 to 152.9.110.254152.9.110.255254
112152.9.111.0/24152.9.111.1 to 152.9.111.254152.9.111.255254
113152.9.112.0/24152.9.112.1 to 152.9.112.254152.9.112.255254
114152.9.113.0/24152.9.113.1 to 152.9.113.254152.9.113.255254
115152.9.114.0/24152.9.114.1 to 152.9.114.254152.9.114.255254
116152.9.115.0/24152.9.115.1 to 152.9.115.254152.9.115.255254
117152.9.116.0/24152.9.116.1 to 152.9.116.254152.9.116.255254
118152.9.117.0/24152.9.117.1 to 152.9.117.254152.9.117.255254
119152.9.118.0/24152.9.118.1 to 152.9.118.254152.9.118.255254
120152.9.119.0/24152.9.119.1 to 152.9.119.254152.9.119.255254
121152.9.120.0/24152.9.120.1 to 152.9.120.254152.9.120.255254
122152.9.121.0/24152.9.121.1 to 152.9.121.254152.9.121.255254
123152.9.122.0/24152.9.122.1 to 152.9.122.254152.9.122.255254
124152.9.123.0/24152.9.123.1 to 152.9.123.254152.9.123.255254
125152.9.124.0/24152.9.124.1 to 152.9.124.254152.9.124.255254
126152.9.125.0/24152.9.125.1 to 152.9.125.254152.9.125.255254
127152.9.126.0/24152.9.126.1 to 152.9.126.254152.9.126.255254
128152.9.127.0/24152.9.127.1 to 152.9.127.254152.9.127.255254
129152.9.128.0/24152.9.128.1 to 152.9.128.254152.9.128.255254
130152.9.129.0/24152.9.129.1 to 152.9.129.254152.9.129.255254
131152.9.130.0/24152.9.130.1 to 152.9.130.254152.9.130.255254
132152.9.131.0/24152.9.131.1 to 152.9.131.254152.9.131.255254
133152.9.132.0/24152.9.132.1 to 152.9.132.254152.9.132.255254
134152.9.133.0/24152.9.133.1 to 152.9.133.254152.9.133.255254
135152.9.134.0/24152.9.134.1 to 152.9.134.254152.9.134.255254
136152.9.135.0/24152.9.135.1 to 152.9.135.254152.9.135.255254
137152.9.136.0/24152.9.136.1 to 152.9.136.254152.9.136.255254
138152.9.137.0/24152.9.137.1 to 152.9.137.254152.9.137.255254
139152.9.138.0/24152.9.138.1 to 152.9.138.254152.9.138.255254
140152.9.139.0/24152.9.139.1 to 152.9.139.254152.9.139.255254
141152.9.140.0/24152.9.140.1 to 152.9.140.254152.9.140.255254
142152.9.141.0/24152.9.141.1 to 152.9.141.254152.9.141.255254
143152.9.142.0/24152.9.142.1 to 152.9.142.254152.9.142.255254
144152.9.143.0/24152.9.143.1 to 152.9.143.254152.9.143.255254
145152.9.144.0/24152.9.144.1 to 152.9.144.254152.9.144.255254
146152.9.145.0/24152.9.145.1 to 152.9.145.254152.9.145.255254
147152.9.146.0/24152.9.146.1 to 152.9.146.254152.9.146.255254
148152.9.147.0/24152.9.147.1 to 152.9.147.254152.9.147.255254
149152.9.148.0/24152.9.148.1 to 152.9.148.254152.9.148.255254
150152.9.149.0/24152.9.149.1 to 152.9.149.254152.9.149.255254
151152.9.150.0/24152.9.150.1 to 152.9.150.254152.9.150.255254
152152.9.151.0/24152.9.151.1 to 152.9.151.254152.9.151.255254
153152.9.152.0/24152.9.152.1 to 152.9.152.254152.9.152.255254
154152.9.153.0/24152.9.153.1 to 152.9.153.254152.9.153.255254
155152.9.154.0/24152.9.154.1 to 152.9.154.254152.9.154.255254
156152.9.155.0/24152.9.155.1 to 152.9.155.254152.9.155.255254
157152.9.156.0/24152.9.156.1 to 152.9.156.254152.9.156.255254
158152.9.157.0/24152.9.157.1 to 152.9.157.254152.9.157.255254
159152.9.158.0/24152.9.158.1 to 152.9.158.254152.9.158.255254
160152.9.159.0/24152.9.159.1 to 152.9.159.254152.9.159.255254
161152.9.160.0/24152.9.160.1 to 152.9.160.254152.9.160.255254
162152.9.161.0/24152.9.161.1 to 152.9.161.254152.9.161.255254
163152.9.162.0/24152.9.162.1 to 152.9.162.254152.9.162.255254
164152.9.163.0/24152.9.163.1 to 152.9.163.254152.9.163.255254
165152.9.164.0/24152.9.164.1 to 152.9.164.254152.9.164.255254
166152.9.165.0/24152.9.165.1 to 152.9.165.254152.9.165.255254
167152.9.166.0/24152.9.166.1 to 152.9.166.254152.9.166.255254
168152.9.167.0/24152.9.167.1 to 152.9.167.254152.9.167.255254
169152.9.168.0/24152.9.168.1 to 152.9.168.254152.9.168.255254
170152.9.169.0/24152.9.169.1 to 152.9.169.254152.9.169.255254
171152.9.170.0/24152.9.170.1 to 152.9.170.254152.9.170.255254
172152.9.171.0/24152.9.171.1 to 152.9.171.254152.9.171.255254
173152.9.172.0/24152.9.172.1 to 152.9.172.254152.9.172.255254
174152.9.173.0/24152.9.173.1 to 152.9.173.254152.9.173.255254
175152.9.174.0/24152.9.174.1 to 152.9.174.254152.9.174.255254
176152.9.175.0/24152.9.175.1 to 152.9.175.254152.9.175.255254
177152.9.176.0/24152.9.176.1 to 152.9.176.254152.9.176.255254
178152.9.177.0/24152.9.177.1 to 152.9.177.254152.9.177.255254
179152.9.178.0/24152.9.178.1 to 152.9.178.254152.9.178.255254
180152.9.179.0/24152.9.179.1 to 152.9.179.254152.9.179.255254
181152.9.180.0/24152.9.180.1 to 152.9.180.254152.9.180.255254
182152.9.181.0/24152.9.181.1 to 152.9.181.254152.9.181.255254
183152.9.182.0/24152.9.182.1 to 152.9.182.254152.9.182.255254
184152.9.183.0/24152.9.183.1 to 152.9.183.254152.9.183.255254
185152.9.184.0/24152.9.184.1 to 152.9.184.254152.9.184.255254
186152.9.185.0/24152.9.185.1 to 152.9.185.254152.9.185.255254
187152.9.186.0/24152.9.186.1 to 152.9.186.254152.9.186.255254
188152.9.187.0/24152.9.187.1 to 152.9.187.254152.9.187.255254
189152.9.188.0/24152.9.188.1 to 152.9.188.254152.9.188.255254
190152.9.189.0/24152.9.189.1 to 152.9.189.254152.9.189.255254
191152.9.190.0/24152.9.190.1 to 152.9.190.254152.9.190.255254
192152.9.191.0/24152.9.191.1 to 152.9.191.254152.9.191.255254
193152.9.192.0/24152.9.192.1 to 152.9.192.254152.9.192.255254
194152.9.193.0/24152.9.193.1 to 152.9.193.254152.9.193.255254
195152.9.194.0/24152.9.194.1 to 152.9.194.254152.9.194.255254
196152.9.195.0/24152.9.195.1 to 152.9.195.254152.9.195.255254
197152.9.196.0/24152.9.196.1 to 152.9.196.254152.9.196.255254
198152.9.197.0/24152.9.197.1 to 152.9.197.254152.9.197.255254
199152.9.198.0/24152.9.198.1 to 152.9.198.254152.9.198.255254
200152.9.199.0/24152.9.199.1 to 152.9.199.254152.9.199.255254
201152.9.200.0/24152.9.200.1 to 152.9.200.254152.9.200.255254
202152.9.201.0/24152.9.201.1 to 152.9.201.254152.9.201.255254
203152.9.202.0/24152.9.202.1 to 152.9.202.254152.9.202.255254
204152.9.203.0/24152.9.203.1 to 152.9.203.254152.9.203.255254
205152.9.204.0/24152.9.204.1 to 152.9.204.254152.9.204.255254
206152.9.205.0/24152.9.205.1 to 152.9.205.254152.9.205.255254
207152.9.206.0/24152.9.206.1 to 152.9.206.254152.9.206.255254
208152.9.207.0/24152.9.207.1 to 152.9.207.254152.9.207.255254
209152.9.208.0/24152.9.208.1 to 152.9.208.254152.9.208.255254
210152.9.209.0/24152.9.209.1 to 152.9.209.254152.9.209.255254
211152.9.210.0/24152.9.210.1 to 152.9.210.254152.9.210.255254
212152.9.211.0/24152.9.211.1 to 152.9.211.254152.9.211.255254
213152.9.212.0/24152.9.212.1 to 152.9.212.254152.9.212.255254
214152.9.213.0/24152.9.213.1 to 152.9.213.254152.9.213.255254
215152.9.214.0/24152.9.214.1 to 152.9.214.254152.9.214.255254
216152.9.215.0/24152.9.215.1 to 152.9.215.254152.9.215.255254
217152.9.216.0/24152.9.216.1 to 152.9.216.254152.9.216.255254
218152.9.217.0/24152.9.217.1 to 152.9.217.254152.9.217.255254
219152.9.218.0/24152.9.218.1 to 152.9.218.254152.9.218.255254
220152.9.219.0/24152.9.219.1 to 152.9.219.254152.9.219.255254
221152.9.220.0/24152.9.220.1 to 152.9.220.254152.9.220.255254
222152.9.221.0/24152.9.221.1 to 152.9.221.254152.9.221.255254
223152.9.222.0/24152.9.222.1 to 152.9.222.254152.9.222.255254
224152.9.223.0/24152.9.223.1 to 152.9.223.254152.9.223.255254
225152.9.224.0/24152.9.224.1 to 152.9.224.254152.9.224.255254
226152.9.225.0/24152.9.225.1 to 152.9.225.254152.9.225.255254
227152.9.226.0/24152.9.226.1 to 152.9.226.254152.9.226.255254
228152.9.227.0/24152.9.227.1 to 152.9.227.254152.9.227.255254
229152.9.228.0/24152.9.228.1 to 152.9.228.254152.9.228.255254
230152.9.229.0/24152.9.229.1 to 152.9.229.254152.9.229.255254
231152.9.230.0/24152.9.230.1 to 152.9.230.254152.9.230.255254
232152.9.231.0/24152.9.231.1 to 152.9.231.254152.9.231.255254
233152.9.232.0/24152.9.232.1 to 152.9.232.254152.9.232.255254
234152.9.233.0/24152.9.233.1 to 152.9.233.254152.9.233.255254
235152.9.234.0/24152.9.234.1 to 152.9.234.254152.9.234.255254
236152.9.235.0/24152.9.235.1 to 152.9.235.254152.9.235.255254
237152.9.236.0/24152.9.236.1 to 152.9.236.254152.9.236.255254
238152.9.237.0/24152.9.237.1 to 152.9.237.254152.9.237.255254
239152.9.238.0/24152.9.238.1 to 152.9.238.254152.9.238.255254
240152.9.239.0/24152.9.239.1 to 152.9.239.254152.9.239.255254
241152.9.240.0/24152.9.240.1 to 152.9.240.254152.9.240.255254
242152.9.241.0/24152.9.241.1 to 152.9.241.254152.9.241.255254
243152.9.242.0/24152.9.242.1 to 152.9.242.254152.9.242.255254
244152.9.243.0/24152.9.243.1 to 152.9.243.254152.9.243.255254
245152.9.244.0/24152.9.244.1 to 152.9.244.254152.9.244.255254
246152.9.245.0/24152.9.245.1 to 152.9.245.254152.9.245.255254
247152.9.246.0/24152.9.246.1 to 152.9.246.254152.9.246.255254
248152.9.247.0/24152.9.247.1 to 152.9.247.254152.9.247.255254
249152.9.248.0/24152.9.248.1 to 152.9.248.254152.9.248.255254
250152.9.249.0/24152.9.249.1 to 152.9.249.254152.9.249.255254
251152.9.250.0/24152.9.250.1 to 152.9.250.254152.9.250.255254
252152.9.251.0/24152.9.251.1 to 152.9.251.254152.9.251.255254
253152.9.252.0/24152.9.252.1 to 152.9.252.254152.9.252.255254
254152.9.253.0/24152.9.253.1 to 152.9.253.254152.9.253.255254
255152.9.254.0/24152.9.254.1 to 152.9.254.254152.9.254.255254
256152.9.255.0/24152.9.255.1 to 152.9.255.254152.9.255.255254

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