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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.

Network152.64.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
152.64.0.0
Broadcast address
152.95.255.255
First usable
152.64.0.1
Last usable
152.95.255.254
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
Public public
Old class
B (default /16)
As numbers
Hex 98400000 · Integer 2554331136 to 2556428287
Reverse DNS zones
64.152.in-addr.arpa
65.152.in-addr.arpa
66.152.in-addr.arpa
67.152.in-addr.arpa
68.152.in-addr.arpa
69.152.in-addr.arpa
70.152.in-addr.arpa
71.152.in-addr.arpa
72.152.in-addr.arpa
73.152.in-addr.arpa
74.152.in-addr.arpa
75.152.in-addr.arpa
76.152.in-addr.arpa
77.152.in-addr.arpa
78.152.in-addr.arpa
79.152.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
Address10011000.01000000.00000000.00000000152.64.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network10011000.01000000.00000000.00000000152.64.0.0
Broadcast10011000.01011111.11111111.11111111152.95.255.255
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)

152.64.0.0/11 makes 4,096 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1152.64.0.0/23152.64.0.1 to 152.64.1.254152.64.1.255510
2152.64.2.0/23152.64.2.1 to 152.64.3.254152.64.3.255510
3152.64.4.0/23152.64.4.1 to 152.64.5.254152.64.5.255510
4152.64.6.0/23152.64.6.1 to 152.64.7.254152.64.7.255510
5152.64.8.0/23152.64.8.1 to 152.64.9.254152.64.9.255510
6152.64.10.0/23152.64.10.1 to 152.64.11.254152.64.11.255510
7152.64.12.0/23152.64.12.1 to 152.64.13.254152.64.13.255510
8152.64.14.0/23152.64.14.1 to 152.64.15.254152.64.15.255510
9152.64.16.0/23152.64.16.1 to 152.64.17.254152.64.17.255510
10152.64.18.0/23152.64.18.1 to 152.64.19.254152.64.19.255510
11152.64.20.0/23152.64.20.1 to 152.64.21.254152.64.21.255510
12152.64.22.0/23152.64.22.1 to 152.64.23.254152.64.23.255510
13152.64.24.0/23152.64.24.1 to 152.64.25.254152.64.25.255510
14152.64.26.0/23152.64.26.1 to 152.64.27.254152.64.27.255510
15152.64.28.0/23152.64.28.1 to 152.64.29.254152.64.29.255510
16152.64.30.0/23152.64.30.1 to 152.64.31.254152.64.31.255510
17152.64.32.0/23152.64.32.1 to 152.64.33.254152.64.33.255510
18152.64.34.0/23152.64.34.1 to 152.64.35.254152.64.35.255510
19152.64.36.0/23152.64.36.1 to 152.64.37.254152.64.37.255510
20152.64.38.0/23152.64.38.1 to 152.64.39.254152.64.39.255510
21152.64.40.0/23152.64.40.1 to 152.64.41.254152.64.41.255510
22152.64.42.0/23152.64.42.1 to 152.64.43.254152.64.43.255510
23152.64.44.0/23152.64.44.1 to 152.64.45.254152.64.45.255510
24152.64.46.0/23152.64.46.1 to 152.64.47.254152.64.47.255510
25152.64.48.0/23152.64.48.1 to 152.64.49.254152.64.49.255510
26152.64.50.0/23152.64.50.1 to 152.64.51.254152.64.51.255510
27152.64.52.0/23152.64.52.1 to 152.64.53.254152.64.53.255510
28152.64.54.0/23152.64.54.1 to 152.64.55.254152.64.55.255510
29152.64.56.0/23152.64.56.1 to 152.64.57.254152.64.57.255510
30152.64.58.0/23152.64.58.1 to 152.64.59.254152.64.59.255510
31152.64.60.0/23152.64.60.1 to 152.64.61.254152.64.61.255510
32152.64.62.0/23152.64.62.1 to 152.64.63.254152.64.63.255510
33152.64.64.0/23152.64.64.1 to 152.64.65.254152.64.65.255510
34152.64.66.0/23152.64.66.1 to 152.64.67.254152.64.67.255510
35152.64.68.0/23152.64.68.1 to 152.64.69.254152.64.69.255510
36152.64.70.0/23152.64.70.1 to 152.64.71.254152.64.71.255510
37152.64.72.0/23152.64.72.1 to 152.64.73.254152.64.73.255510
38152.64.74.0/23152.64.74.1 to 152.64.75.254152.64.75.255510
39152.64.76.0/23152.64.76.1 to 152.64.77.254152.64.77.255510
40152.64.78.0/23152.64.78.1 to 152.64.79.254152.64.79.255510
41152.64.80.0/23152.64.80.1 to 152.64.81.254152.64.81.255510
42152.64.82.0/23152.64.82.1 to 152.64.83.254152.64.83.255510
43152.64.84.0/23152.64.84.1 to 152.64.85.254152.64.85.255510
44152.64.86.0/23152.64.86.1 to 152.64.87.254152.64.87.255510
45152.64.88.0/23152.64.88.1 to 152.64.89.254152.64.89.255510
46152.64.90.0/23152.64.90.1 to 152.64.91.254152.64.91.255510
47152.64.92.0/23152.64.92.1 to 152.64.93.254152.64.93.255510
48152.64.94.0/23152.64.94.1 to 152.64.95.254152.64.95.255510
49152.64.96.0/23152.64.96.1 to 152.64.97.254152.64.97.255510
50152.64.98.0/23152.64.98.1 to 152.64.99.254152.64.99.255510
51152.64.100.0/23152.64.100.1 to 152.64.101.254152.64.101.255510
52152.64.102.0/23152.64.102.1 to 152.64.103.254152.64.103.255510
53152.64.104.0/23152.64.104.1 to 152.64.105.254152.64.105.255510
54152.64.106.0/23152.64.106.1 to 152.64.107.254152.64.107.255510
55152.64.108.0/23152.64.108.1 to 152.64.109.254152.64.109.255510
56152.64.110.0/23152.64.110.1 to 152.64.111.254152.64.111.255510
57152.64.112.0/23152.64.112.1 to 152.64.113.254152.64.113.255510
58152.64.114.0/23152.64.114.1 to 152.64.115.254152.64.115.255510
59152.64.116.0/23152.64.116.1 to 152.64.117.254152.64.117.255510
60152.64.118.0/23152.64.118.1 to 152.64.119.254152.64.119.255510
61152.64.120.0/23152.64.120.1 to 152.64.121.254152.64.121.255510
62152.64.122.0/23152.64.122.1 to 152.64.123.254152.64.123.255510
63152.64.124.0/23152.64.124.1 to 152.64.125.254152.64.125.255510
64152.64.126.0/23152.64.126.1 to 152.64.127.254152.64.127.255510
65152.64.128.0/23152.64.128.1 to 152.64.129.254152.64.129.255510
66152.64.130.0/23152.64.130.1 to 152.64.131.254152.64.131.255510
67152.64.132.0/23152.64.132.1 to 152.64.133.254152.64.133.255510
68152.64.134.0/23152.64.134.1 to 152.64.135.254152.64.135.255510
69152.64.136.0/23152.64.136.1 to 152.64.137.254152.64.137.255510
70152.64.138.0/23152.64.138.1 to 152.64.139.254152.64.139.255510
71152.64.140.0/23152.64.140.1 to 152.64.141.254152.64.141.255510
72152.64.142.0/23152.64.142.1 to 152.64.143.254152.64.143.255510
73152.64.144.0/23152.64.144.1 to 152.64.145.254152.64.145.255510
74152.64.146.0/23152.64.146.1 to 152.64.147.254152.64.147.255510
75152.64.148.0/23152.64.148.1 to 152.64.149.254152.64.149.255510
76152.64.150.0/23152.64.150.1 to 152.64.151.254152.64.151.255510
77152.64.152.0/23152.64.152.1 to 152.64.153.254152.64.153.255510
78152.64.154.0/23152.64.154.1 to 152.64.155.254152.64.155.255510
79152.64.156.0/23152.64.156.1 to 152.64.157.254152.64.157.255510
80152.64.158.0/23152.64.158.1 to 152.64.159.254152.64.159.255510
81152.64.160.0/23152.64.160.1 to 152.64.161.254152.64.161.255510
82152.64.162.0/23152.64.162.1 to 152.64.163.254152.64.163.255510
83152.64.164.0/23152.64.164.1 to 152.64.165.254152.64.165.255510
84152.64.166.0/23152.64.166.1 to 152.64.167.254152.64.167.255510
85152.64.168.0/23152.64.168.1 to 152.64.169.254152.64.169.255510
86152.64.170.0/23152.64.170.1 to 152.64.171.254152.64.171.255510
87152.64.172.0/23152.64.172.1 to 152.64.173.254152.64.173.255510
88152.64.174.0/23152.64.174.1 to 152.64.175.254152.64.175.255510
89152.64.176.0/23152.64.176.1 to 152.64.177.254152.64.177.255510
90152.64.178.0/23152.64.178.1 to 152.64.179.254152.64.179.255510
91152.64.180.0/23152.64.180.1 to 152.64.181.254152.64.181.255510
92152.64.182.0/23152.64.182.1 to 152.64.183.254152.64.183.255510
93152.64.184.0/23152.64.184.1 to 152.64.185.254152.64.185.255510
94152.64.186.0/23152.64.186.1 to 152.64.187.254152.64.187.255510
95152.64.188.0/23152.64.188.1 to 152.64.189.254152.64.189.255510
96152.64.190.0/23152.64.190.1 to 152.64.191.254152.64.191.255510
97152.64.192.0/23152.64.192.1 to 152.64.193.254152.64.193.255510
98152.64.194.0/23152.64.194.1 to 152.64.195.254152.64.195.255510
99152.64.196.0/23152.64.196.1 to 152.64.197.254152.64.197.255510
100152.64.198.0/23152.64.198.1 to 152.64.199.254152.64.199.255510
101152.64.200.0/23152.64.200.1 to 152.64.201.254152.64.201.255510
102152.64.202.0/23152.64.202.1 to 152.64.203.254152.64.203.255510
103152.64.204.0/23152.64.204.1 to 152.64.205.254152.64.205.255510
104152.64.206.0/23152.64.206.1 to 152.64.207.254152.64.207.255510
105152.64.208.0/23152.64.208.1 to 152.64.209.254152.64.209.255510
106152.64.210.0/23152.64.210.1 to 152.64.211.254152.64.211.255510
107152.64.212.0/23152.64.212.1 to 152.64.213.254152.64.213.255510
108152.64.214.0/23152.64.214.1 to 152.64.215.254152.64.215.255510
109152.64.216.0/23152.64.216.1 to 152.64.217.254152.64.217.255510
110152.64.218.0/23152.64.218.1 to 152.64.219.254152.64.219.255510
111152.64.220.0/23152.64.220.1 to 152.64.221.254152.64.221.255510
112152.64.222.0/23152.64.222.1 to 152.64.223.254152.64.223.255510
113152.64.224.0/23152.64.224.1 to 152.64.225.254152.64.225.255510
114152.64.226.0/23152.64.226.1 to 152.64.227.254152.64.227.255510
115152.64.228.0/23152.64.228.1 to 152.64.229.254152.64.229.255510
116152.64.230.0/23152.64.230.1 to 152.64.231.254152.64.231.255510
117152.64.232.0/23152.64.232.1 to 152.64.233.254152.64.233.255510
118152.64.234.0/23152.64.234.1 to 152.64.235.254152.64.235.255510
119152.64.236.0/23152.64.236.1 to 152.64.237.254152.64.237.255510
120152.64.238.0/23152.64.238.1 to 152.64.239.254152.64.239.255510
121152.64.240.0/23152.64.240.1 to 152.64.241.254152.64.241.255510
122152.64.242.0/23152.64.242.1 to 152.64.243.254152.64.243.255510
123152.64.244.0/23152.64.244.1 to 152.64.245.254152.64.245.255510
124152.64.246.0/23152.64.246.1 to 152.64.247.254152.64.247.255510
125152.64.248.0/23152.64.248.1 to 152.64.249.254152.64.249.255510
126152.64.250.0/23152.64.250.1 to 152.64.251.254152.64.251.255510
127152.64.252.0/23152.64.252.1 to 152.64.253.254152.64.253.255510
128152.64.254.0/23152.64.254.1 to 152.64.255.254152.64.255.255510
129152.65.0.0/23152.65.0.1 to 152.65.1.254152.65.1.255510
130152.65.2.0/23152.65.2.1 to 152.65.3.254152.65.3.255510
131152.65.4.0/23152.65.4.1 to 152.65.5.254152.65.5.255510
132152.65.6.0/23152.65.6.1 to 152.65.7.254152.65.7.255510
133152.65.8.0/23152.65.8.1 to 152.65.9.254152.65.9.255510
134152.65.10.0/23152.65.10.1 to 152.65.11.254152.65.11.255510
135152.65.12.0/23152.65.12.1 to 152.65.13.254152.65.13.255510
136152.65.14.0/23152.65.14.1 to 152.65.15.254152.65.15.255510
137152.65.16.0/23152.65.16.1 to 152.65.17.254152.65.17.255510
138152.65.18.0/23152.65.18.1 to 152.65.19.254152.65.19.255510
139152.65.20.0/23152.65.20.1 to 152.65.21.254152.65.21.255510
140152.65.22.0/23152.65.22.1 to 152.65.23.254152.65.23.255510
141152.65.24.0/23152.65.24.1 to 152.65.25.254152.65.25.255510
142152.65.26.0/23152.65.26.1 to 152.65.27.254152.65.27.255510
143152.65.28.0/23152.65.28.1 to 152.65.29.254152.65.29.255510
144152.65.30.0/23152.65.30.1 to 152.65.31.254152.65.31.255510
145152.65.32.0/23152.65.32.1 to 152.65.33.254152.65.33.255510
146152.65.34.0/23152.65.34.1 to 152.65.35.254152.65.35.255510
147152.65.36.0/23152.65.36.1 to 152.65.37.254152.65.37.255510
148152.65.38.0/23152.65.38.1 to 152.65.39.254152.65.39.255510
149152.65.40.0/23152.65.40.1 to 152.65.41.254152.65.41.255510
150152.65.42.0/23152.65.42.1 to 152.65.43.254152.65.43.255510
151152.65.44.0/23152.65.44.1 to 152.65.45.254152.65.45.255510
152152.65.46.0/23152.65.46.1 to 152.65.47.254152.65.47.255510
153152.65.48.0/23152.65.48.1 to 152.65.49.254152.65.49.255510
154152.65.50.0/23152.65.50.1 to 152.65.51.254152.65.51.255510
155152.65.52.0/23152.65.52.1 to 152.65.53.254152.65.53.255510
156152.65.54.0/23152.65.54.1 to 152.65.55.254152.65.55.255510
157152.65.56.0/23152.65.56.1 to 152.65.57.254152.65.57.255510
158152.65.58.0/23152.65.58.1 to 152.65.59.254152.65.59.255510
159152.65.60.0/23152.65.60.1 to 152.65.61.254152.65.61.255510
160152.65.62.0/23152.65.62.1 to 152.65.63.254152.65.63.255510
161152.65.64.0/23152.65.64.1 to 152.65.65.254152.65.65.255510
162152.65.66.0/23152.65.66.1 to 152.65.67.254152.65.67.255510
163152.65.68.0/23152.65.68.1 to 152.65.69.254152.65.69.255510
164152.65.70.0/23152.65.70.1 to 152.65.71.254152.65.71.255510
165152.65.72.0/23152.65.72.1 to 152.65.73.254152.65.73.255510
166152.65.74.0/23152.65.74.1 to 152.65.75.254152.65.75.255510
167152.65.76.0/23152.65.76.1 to 152.65.77.254152.65.77.255510
168152.65.78.0/23152.65.78.1 to 152.65.79.254152.65.79.255510
169152.65.80.0/23152.65.80.1 to 152.65.81.254152.65.81.255510
170152.65.82.0/23152.65.82.1 to 152.65.83.254152.65.83.255510
171152.65.84.0/23152.65.84.1 to 152.65.85.254152.65.85.255510
172152.65.86.0/23152.65.86.1 to 152.65.87.254152.65.87.255510
173152.65.88.0/23152.65.88.1 to 152.65.89.254152.65.89.255510
174152.65.90.0/23152.65.90.1 to 152.65.91.254152.65.91.255510
175152.65.92.0/23152.65.92.1 to 152.65.93.254152.65.93.255510
176152.65.94.0/23152.65.94.1 to 152.65.95.254152.65.95.255510
177152.65.96.0/23152.65.96.1 to 152.65.97.254152.65.97.255510
178152.65.98.0/23152.65.98.1 to 152.65.99.254152.65.99.255510
179152.65.100.0/23152.65.100.1 to 152.65.101.254152.65.101.255510
180152.65.102.0/23152.65.102.1 to 152.65.103.254152.65.103.255510
181152.65.104.0/23152.65.104.1 to 152.65.105.254152.65.105.255510
182152.65.106.0/23152.65.106.1 to 152.65.107.254152.65.107.255510
183152.65.108.0/23152.65.108.1 to 152.65.109.254152.65.109.255510
184152.65.110.0/23152.65.110.1 to 152.65.111.254152.65.111.255510
185152.65.112.0/23152.65.112.1 to 152.65.113.254152.65.113.255510
186152.65.114.0/23152.65.114.1 to 152.65.115.254152.65.115.255510
187152.65.116.0/23152.65.116.1 to 152.65.117.254152.65.117.255510
188152.65.118.0/23152.65.118.1 to 152.65.119.254152.65.119.255510
189152.65.120.0/23152.65.120.1 to 152.65.121.254152.65.121.255510
190152.65.122.0/23152.65.122.1 to 152.65.123.254152.65.123.255510
191152.65.124.0/23152.65.124.1 to 152.65.125.254152.65.125.255510
192152.65.126.0/23152.65.126.1 to 152.65.127.254152.65.127.255510
193152.65.128.0/23152.65.128.1 to 152.65.129.254152.65.129.255510
194152.65.130.0/23152.65.130.1 to 152.65.131.254152.65.131.255510
195152.65.132.0/23152.65.132.1 to 152.65.133.254152.65.133.255510
196152.65.134.0/23152.65.134.1 to 152.65.135.254152.65.135.255510
197152.65.136.0/23152.65.136.1 to 152.65.137.254152.65.137.255510
198152.65.138.0/23152.65.138.1 to 152.65.139.254152.65.139.255510
199152.65.140.0/23152.65.140.1 to 152.65.141.254152.65.141.255510
200152.65.142.0/23152.65.142.1 to 152.65.143.254152.65.143.255510
201152.65.144.0/23152.65.144.1 to 152.65.145.254152.65.145.255510
202152.65.146.0/23152.65.146.1 to 152.65.147.254152.65.147.255510
203152.65.148.0/23152.65.148.1 to 152.65.149.254152.65.149.255510
204152.65.150.0/23152.65.150.1 to 152.65.151.254152.65.151.255510
205152.65.152.0/23152.65.152.1 to 152.65.153.254152.65.153.255510
206152.65.154.0/23152.65.154.1 to 152.65.155.254152.65.155.255510
207152.65.156.0/23152.65.156.1 to 152.65.157.254152.65.157.255510
208152.65.158.0/23152.65.158.1 to 152.65.159.254152.65.159.255510
209152.65.160.0/23152.65.160.1 to 152.65.161.254152.65.161.255510
210152.65.162.0/23152.65.162.1 to 152.65.163.254152.65.163.255510
211152.65.164.0/23152.65.164.1 to 152.65.165.254152.65.165.255510
212152.65.166.0/23152.65.166.1 to 152.65.167.254152.65.167.255510
213152.65.168.0/23152.65.168.1 to 152.65.169.254152.65.169.255510
214152.65.170.0/23152.65.170.1 to 152.65.171.254152.65.171.255510
215152.65.172.0/23152.65.172.1 to 152.65.173.254152.65.173.255510
216152.65.174.0/23152.65.174.1 to 152.65.175.254152.65.175.255510
217152.65.176.0/23152.65.176.1 to 152.65.177.254152.65.177.255510
218152.65.178.0/23152.65.178.1 to 152.65.179.254152.65.179.255510
219152.65.180.0/23152.65.180.1 to 152.65.181.254152.65.181.255510
220152.65.182.0/23152.65.182.1 to 152.65.183.254152.65.183.255510
221152.65.184.0/23152.65.184.1 to 152.65.185.254152.65.185.255510
222152.65.186.0/23152.65.186.1 to 152.65.187.254152.65.187.255510
223152.65.188.0/23152.65.188.1 to 152.65.189.254152.65.189.255510
224152.65.190.0/23152.65.190.1 to 152.65.191.254152.65.191.255510
225152.65.192.0/23152.65.192.1 to 152.65.193.254152.65.193.255510
226152.65.194.0/23152.65.194.1 to 152.65.195.254152.65.195.255510
227152.65.196.0/23152.65.196.1 to 152.65.197.254152.65.197.255510
228152.65.198.0/23152.65.198.1 to 152.65.199.254152.65.199.255510
229152.65.200.0/23152.65.200.1 to 152.65.201.254152.65.201.255510
230152.65.202.0/23152.65.202.1 to 152.65.203.254152.65.203.255510
231152.65.204.0/23152.65.204.1 to 152.65.205.254152.65.205.255510
232152.65.206.0/23152.65.206.1 to 152.65.207.254152.65.207.255510
233152.65.208.0/23152.65.208.1 to 152.65.209.254152.65.209.255510
234152.65.210.0/23152.65.210.1 to 152.65.211.254152.65.211.255510
235152.65.212.0/23152.65.212.1 to 152.65.213.254152.65.213.255510
236152.65.214.0/23152.65.214.1 to 152.65.215.254152.65.215.255510
237152.65.216.0/23152.65.216.1 to 152.65.217.254152.65.217.255510
238152.65.218.0/23152.65.218.1 to 152.65.219.254152.65.219.255510
239152.65.220.0/23152.65.220.1 to 152.65.221.254152.65.221.255510
240152.65.222.0/23152.65.222.1 to 152.65.223.254152.65.223.255510
241152.65.224.0/23152.65.224.1 to 152.65.225.254152.65.225.255510
242152.65.226.0/23152.65.226.1 to 152.65.227.254152.65.227.255510
243152.65.228.0/23152.65.228.1 to 152.65.229.254152.65.229.255510
244152.65.230.0/23152.65.230.1 to 152.65.231.254152.65.231.255510
245152.65.232.0/23152.65.232.1 to 152.65.233.254152.65.233.255510
246152.65.234.0/23152.65.234.1 to 152.65.235.254152.65.235.255510
247152.65.236.0/23152.65.236.1 to 152.65.237.254152.65.237.255510
248152.65.238.0/23152.65.238.1 to 152.65.239.254152.65.239.255510
249152.65.240.0/23152.65.240.1 to 152.65.241.254152.65.241.255510
250152.65.242.0/23152.65.242.1 to 152.65.243.254152.65.243.255510
251152.65.244.0/23152.65.244.1 to 152.65.245.254152.65.245.255510
252152.65.246.0/23152.65.246.1 to 152.65.247.254152.65.247.255510
253152.65.248.0/23152.65.248.1 to 152.65.249.254152.65.249.255510
254152.65.250.0/23152.65.250.1 to 152.65.251.254152.65.251.255510
255152.65.252.0/23152.65.252.1 to 152.65.253.254152.65.253.255510
256152.65.254.0/23152.65.254.1 to 152.65.255.254152.65.255.255510

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.