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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.

Network114.71.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
114.71.0.0
Broadcast address
114.71.255.255
First usable
114.71.0.1
Last usable
114.71.255.254
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
A (default /8)
As numbers
Hex 72470000 · Integer 1917255680 to 1917321215
Reverse DNS zone
71.114.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110010.01000111..00000000.00000000114.71.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01110010.01000111..00000000.00000000114.71.0.0
Broadcast01110010.01000111..11111111.11111111114.71.255.255
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

114.71.0.0/16 makes 256 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1114.71.0.0/24114.71.0.1 to 114.71.0.254114.71.0.255254
2114.71.1.0/24114.71.1.1 to 114.71.1.254114.71.1.255254
3114.71.2.0/24114.71.2.1 to 114.71.2.254114.71.2.255254
4114.71.3.0/24114.71.3.1 to 114.71.3.254114.71.3.255254
5114.71.4.0/24114.71.4.1 to 114.71.4.254114.71.4.255254
6114.71.5.0/24114.71.5.1 to 114.71.5.254114.71.5.255254
7114.71.6.0/24114.71.6.1 to 114.71.6.254114.71.6.255254
8114.71.7.0/24114.71.7.1 to 114.71.7.254114.71.7.255254
9114.71.8.0/24114.71.8.1 to 114.71.8.254114.71.8.255254
10114.71.9.0/24114.71.9.1 to 114.71.9.254114.71.9.255254
11114.71.10.0/24114.71.10.1 to 114.71.10.254114.71.10.255254
12114.71.11.0/24114.71.11.1 to 114.71.11.254114.71.11.255254
13114.71.12.0/24114.71.12.1 to 114.71.12.254114.71.12.255254
14114.71.13.0/24114.71.13.1 to 114.71.13.254114.71.13.255254
15114.71.14.0/24114.71.14.1 to 114.71.14.254114.71.14.255254
16114.71.15.0/24114.71.15.1 to 114.71.15.254114.71.15.255254
17114.71.16.0/24114.71.16.1 to 114.71.16.254114.71.16.255254
18114.71.17.0/24114.71.17.1 to 114.71.17.254114.71.17.255254
19114.71.18.0/24114.71.18.1 to 114.71.18.254114.71.18.255254
20114.71.19.0/24114.71.19.1 to 114.71.19.254114.71.19.255254
21114.71.20.0/24114.71.20.1 to 114.71.20.254114.71.20.255254
22114.71.21.0/24114.71.21.1 to 114.71.21.254114.71.21.255254
23114.71.22.0/24114.71.22.1 to 114.71.22.254114.71.22.255254
24114.71.23.0/24114.71.23.1 to 114.71.23.254114.71.23.255254
25114.71.24.0/24114.71.24.1 to 114.71.24.254114.71.24.255254
26114.71.25.0/24114.71.25.1 to 114.71.25.254114.71.25.255254
27114.71.26.0/24114.71.26.1 to 114.71.26.254114.71.26.255254
28114.71.27.0/24114.71.27.1 to 114.71.27.254114.71.27.255254
29114.71.28.0/24114.71.28.1 to 114.71.28.254114.71.28.255254
30114.71.29.0/24114.71.29.1 to 114.71.29.254114.71.29.255254
31114.71.30.0/24114.71.30.1 to 114.71.30.254114.71.30.255254
32114.71.31.0/24114.71.31.1 to 114.71.31.254114.71.31.255254
33114.71.32.0/24114.71.32.1 to 114.71.32.254114.71.32.255254
34114.71.33.0/24114.71.33.1 to 114.71.33.254114.71.33.255254
35114.71.34.0/24114.71.34.1 to 114.71.34.254114.71.34.255254
36114.71.35.0/24114.71.35.1 to 114.71.35.254114.71.35.255254
37114.71.36.0/24114.71.36.1 to 114.71.36.254114.71.36.255254
38114.71.37.0/24114.71.37.1 to 114.71.37.254114.71.37.255254
39114.71.38.0/24114.71.38.1 to 114.71.38.254114.71.38.255254
40114.71.39.0/24114.71.39.1 to 114.71.39.254114.71.39.255254
41114.71.40.0/24114.71.40.1 to 114.71.40.254114.71.40.255254
42114.71.41.0/24114.71.41.1 to 114.71.41.254114.71.41.255254
43114.71.42.0/24114.71.42.1 to 114.71.42.254114.71.42.255254
44114.71.43.0/24114.71.43.1 to 114.71.43.254114.71.43.255254
45114.71.44.0/24114.71.44.1 to 114.71.44.254114.71.44.255254
46114.71.45.0/24114.71.45.1 to 114.71.45.254114.71.45.255254
47114.71.46.0/24114.71.46.1 to 114.71.46.254114.71.46.255254
48114.71.47.0/24114.71.47.1 to 114.71.47.254114.71.47.255254
49114.71.48.0/24114.71.48.1 to 114.71.48.254114.71.48.255254
50114.71.49.0/24114.71.49.1 to 114.71.49.254114.71.49.255254
51114.71.50.0/24114.71.50.1 to 114.71.50.254114.71.50.255254
52114.71.51.0/24114.71.51.1 to 114.71.51.254114.71.51.255254
53114.71.52.0/24114.71.52.1 to 114.71.52.254114.71.52.255254
54114.71.53.0/24114.71.53.1 to 114.71.53.254114.71.53.255254
55114.71.54.0/24114.71.54.1 to 114.71.54.254114.71.54.255254
56114.71.55.0/24114.71.55.1 to 114.71.55.254114.71.55.255254
57114.71.56.0/24114.71.56.1 to 114.71.56.254114.71.56.255254
58114.71.57.0/24114.71.57.1 to 114.71.57.254114.71.57.255254
59114.71.58.0/24114.71.58.1 to 114.71.58.254114.71.58.255254
60114.71.59.0/24114.71.59.1 to 114.71.59.254114.71.59.255254
61114.71.60.0/24114.71.60.1 to 114.71.60.254114.71.60.255254
62114.71.61.0/24114.71.61.1 to 114.71.61.254114.71.61.255254
63114.71.62.0/24114.71.62.1 to 114.71.62.254114.71.62.255254
64114.71.63.0/24114.71.63.1 to 114.71.63.254114.71.63.255254
65114.71.64.0/24114.71.64.1 to 114.71.64.254114.71.64.255254
66114.71.65.0/24114.71.65.1 to 114.71.65.254114.71.65.255254
67114.71.66.0/24114.71.66.1 to 114.71.66.254114.71.66.255254
68114.71.67.0/24114.71.67.1 to 114.71.67.254114.71.67.255254
69114.71.68.0/24114.71.68.1 to 114.71.68.254114.71.68.255254
70114.71.69.0/24114.71.69.1 to 114.71.69.254114.71.69.255254
71114.71.70.0/24114.71.70.1 to 114.71.70.254114.71.70.255254
72114.71.71.0/24114.71.71.1 to 114.71.71.254114.71.71.255254
73114.71.72.0/24114.71.72.1 to 114.71.72.254114.71.72.255254
74114.71.73.0/24114.71.73.1 to 114.71.73.254114.71.73.255254
75114.71.74.0/24114.71.74.1 to 114.71.74.254114.71.74.255254
76114.71.75.0/24114.71.75.1 to 114.71.75.254114.71.75.255254
77114.71.76.0/24114.71.76.1 to 114.71.76.254114.71.76.255254
78114.71.77.0/24114.71.77.1 to 114.71.77.254114.71.77.255254
79114.71.78.0/24114.71.78.1 to 114.71.78.254114.71.78.255254
80114.71.79.0/24114.71.79.1 to 114.71.79.254114.71.79.255254
81114.71.80.0/24114.71.80.1 to 114.71.80.254114.71.80.255254
82114.71.81.0/24114.71.81.1 to 114.71.81.254114.71.81.255254
83114.71.82.0/24114.71.82.1 to 114.71.82.254114.71.82.255254
84114.71.83.0/24114.71.83.1 to 114.71.83.254114.71.83.255254
85114.71.84.0/24114.71.84.1 to 114.71.84.254114.71.84.255254
86114.71.85.0/24114.71.85.1 to 114.71.85.254114.71.85.255254
87114.71.86.0/24114.71.86.1 to 114.71.86.254114.71.86.255254
88114.71.87.0/24114.71.87.1 to 114.71.87.254114.71.87.255254
89114.71.88.0/24114.71.88.1 to 114.71.88.254114.71.88.255254
90114.71.89.0/24114.71.89.1 to 114.71.89.254114.71.89.255254
91114.71.90.0/24114.71.90.1 to 114.71.90.254114.71.90.255254
92114.71.91.0/24114.71.91.1 to 114.71.91.254114.71.91.255254
93114.71.92.0/24114.71.92.1 to 114.71.92.254114.71.92.255254
94114.71.93.0/24114.71.93.1 to 114.71.93.254114.71.93.255254
95114.71.94.0/24114.71.94.1 to 114.71.94.254114.71.94.255254
96114.71.95.0/24114.71.95.1 to 114.71.95.254114.71.95.255254
97114.71.96.0/24114.71.96.1 to 114.71.96.254114.71.96.255254
98114.71.97.0/24114.71.97.1 to 114.71.97.254114.71.97.255254
99114.71.98.0/24114.71.98.1 to 114.71.98.254114.71.98.255254
100114.71.99.0/24114.71.99.1 to 114.71.99.254114.71.99.255254
101114.71.100.0/24114.71.100.1 to 114.71.100.254114.71.100.255254
102114.71.101.0/24114.71.101.1 to 114.71.101.254114.71.101.255254
103114.71.102.0/24114.71.102.1 to 114.71.102.254114.71.102.255254
104114.71.103.0/24114.71.103.1 to 114.71.103.254114.71.103.255254
105114.71.104.0/24114.71.104.1 to 114.71.104.254114.71.104.255254
106114.71.105.0/24114.71.105.1 to 114.71.105.254114.71.105.255254
107114.71.106.0/24114.71.106.1 to 114.71.106.254114.71.106.255254
108114.71.107.0/24114.71.107.1 to 114.71.107.254114.71.107.255254
109114.71.108.0/24114.71.108.1 to 114.71.108.254114.71.108.255254
110114.71.109.0/24114.71.109.1 to 114.71.109.254114.71.109.255254
111114.71.110.0/24114.71.110.1 to 114.71.110.254114.71.110.255254
112114.71.111.0/24114.71.111.1 to 114.71.111.254114.71.111.255254
113114.71.112.0/24114.71.112.1 to 114.71.112.254114.71.112.255254
114114.71.113.0/24114.71.113.1 to 114.71.113.254114.71.113.255254
115114.71.114.0/24114.71.114.1 to 114.71.114.254114.71.114.255254
116114.71.115.0/24114.71.115.1 to 114.71.115.254114.71.115.255254
117114.71.116.0/24114.71.116.1 to 114.71.116.254114.71.116.255254
118114.71.117.0/24114.71.117.1 to 114.71.117.254114.71.117.255254
119114.71.118.0/24114.71.118.1 to 114.71.118.254114.71.118.255254
120114.71.119.0/24114.71.119.1 to 114.71.119.254114.71.119.255254
121114.71.120.0/24114.71.120.1 to 114.71.120.254114.71.120.255254
122114.71.121.0/24114.71.121.1 to 114.71.121.254114.71.121.255254
123114.71.122.0/24114.71.122.1 to 114.71.122.254114.71.122.255254
124114.71.123.0/24114.71.123.1 to 114.71.123.254114.71.123.255254
125114.71.124.0/24114.71.124.1 to 114.71.124.254114.71.124.255254
126114.71.125.0/24114.71.125.1 to 114.71.125.254114.71.125.255254
127114.71.126.0/24114.71.126.1 to 114.71.126.254114.71.126.255254
128114.71.127.0/24114.71.127.1 to 114.71.127.254114.71.127.255254
129114.71.128.0/24114.71.128.1 to 114.71.128.254114.71.128.255254
130114.71.129.0/24114.71.129.1 to 114.71.129.254114.71.129.255254
131114.71.130.0/24114.71.130.1 to 114.71.130.254114.71.130.255254
132114.71.131.0/24114.71.131.1 to 114.71.131.254114.71.131.255254
133114.71.132.0/24114.71.132.1 to 114.71.132.254114.71.132.255254
134114.71.133.0/24114.71.133.1 to 114.71.133.254114.71.133.255254
135114.71.134.0/24114.71.134.1 to 114.71.134.254114.71.134.255254
136114.71.135.0/24114.71.135.1 to 114.71.135.254114.71.135.255254
137114.71.136.0/24114.71.136.1 to 114.71.136.254114.71.136.255254
138114.71.137.0/24114.71.137.1 to 114.71.137.254114.71.137.255254
139114.71.138.0/24114.71.138.1 to 114.71.138.254114.71.138.255254
140114.71.139.0/24114.71.139.1 to 114.71.139.254114.71.139.255254
141114.71.140.0/24114.71.140.1 to 114.71.140.254114.71.140.255254
142114.71.141.0/24114.71.141.1 to 114.71.141.254114.71.141.255254
143114.71.142.0/24114.71.142.1 to 114.71.142.254114.71.142.255254
144114.71.143.0/24114.71.143.1 to 114.71.143.254114.71.143.255254
145114.71.144.0/24114.71.144.1 to 114.71.144.254114.71.144.255254
146114.71.145.0/24114.71.145.1 to 114.71.145.254114.71.145.255254
147114.71.146.0/24114.71.146.1 to 114.71.146.254114.71.146.255254
148114.71.147.0/24114.71.147.1 to 114.71.147.254114.71.147.255254
149114.71.148.0/24114.71.148.1 to 114.71.148.254114.71.148.255254
150114.71.149.0/24114.71.149.1 to 114.71.149.254114.71.149.255254
151114.71.150.0/24114.71.150.1 to 114.71.150.254114.71.150.255254
152114.71.151.0/24114.71.151.1 to 114.71.151.254114.71.151.255254
153114.71.152.0/24114.71.152.1 to 114.71.152.254114.71.152.255254
154114.71.153.0/24114.71.153.1 to 114.71.153.254114.71.153.255254
155114.71.154.0/24114.71.154.1 to 114.71.154.254114.71.154.255254
156114.71.155.0/24114.71.155.1 to 114.71.155.254114.71.155.255254
157114.71.156.0/24114.71.156.1 to 114.71.156.254114.71.156.255254
158114.71.157.0/24114.71.157.1 to 114.71.157.254114.71.157.255254
159114.71.158.0/24114.71.158.1 to 114.71.158.254114.71.158.255254
160114.71.159.0/24114.71.159.1 to 114.71.159.254114.71.159.255254
161114.71.160.0/24114.71.160.1 to 114.71.160.254114.71.160.255254
162114.71.161.0/24114.71.161.1 to 114.71.161.254114.71.161.255254
163114.71.162.0/24114.71.162.1 to 114.71.162.254114.71.162.255254
164114.71.163.0/24114.71.163.1 to 114.71.163.254114.71.163.255254
165114.71.164.0/24114.71.164.1 to 114.71.164.254114.71.164.255254
166114.71.165.0/24114.71.165.1 to 114.71.165.254114.71.165.255254
167114.71.166.0/24114.71.166.1 to 114.71.166.254114.71.166.255254
168114.71.167.0/24114.71.167.1 to 114.71.167.254114.71.167.255254
169114.71.168.0/24114.71.168.1 to 114.71.168.254114.71.168.255254
170114.71.169.0/24114.71.169.1 to 114.71.169.254114.71.169.255254
171114.71.170.0/24114.71.170.1 to 114.71.170.254114.71.170.255254
172114.71.171.0/24114.71.171.1 to 114.71.171.254114.71.171.255254
173114.71.172.0/24114.71.172.1 to 114.71.172.254114.71.172.255254
174114.71.173.0/24114.71.173.1 to 114.71.173.254114.71.173.255254
175114.71.174.0/24114.71.174.1 to 114.71.174.254114.71.174.255254
176114.71.175.0/24114.71.175.1 to 114.71.175.254114.71.175.255254
177114.71.176.0/24114.71.176.1 to 114.71.176.254114.71.176.255254
178114.71.177.0/24114.71.177.1 to 114.71.177.254114.71.177.255254
179114.71.178.0/24114.71.178.1 to 114.71.178.254114.71.178.255254
180114.71.179.0/24114.71.179.1 to 114.71.179.254114.71.179.255254
181114.71.180.0/24114.71.180.1 to 114.71.180.254114.71.180.255254
182114.71.181.0/24114.71.181.1 to 114.71.181.254114.71.181.255254
183114.71.182.0/24114.71.182.1 to 114.71.182.254114.71.182.255254
184114.71.183.0/24114.71.183.1 to 114.71.183.254114.71.183.255254
185114.71.184.0/24114.71.184.1 to 114.71.184.254114.71.184.255254
186114.71.185.0/24114.71.185.1 to 114.71.185.254114.71.185.255254
187114.71.186.0/24114.71.186.1 to 114.71.186.254114.71.186.255254
188114.71.187.0/24114.71.187.1 to 114.71.187.254114.71.187.255254
189114.71.188.0/24114.71.188.1 to 114.71.188.254114.71.188.255254
190114.71.189.0/24114.71.189.1 to 114.71.189.254114.71.189.255254
191114.71.190.0/24114.71.190.1 to 114.71.190.254114.71.190.255254
192114.71.191.0/24114.71.191.1 to 114.71.191.254114.71.191.255254
193114.71.192.0/24114.71.192.1 to 114.71.192.254114.71.192.255254
194114.71.193.0/24114.71.193.1 to 114.71.193.254114.71.193.255254
195114.71.194.0/24114.71.194.1 to 114.71.194.254114.71.194.255254
196114.71.195.0/24114.71.195.1 to 114.71.195.254114.71.195.255254
197114.71.196.0/24114.71.196.1 to 114.71.196.254114.71.196.255254
198114.71.197.0/24114.71.197.1 to 114.71.197.254114.71.197.255254
199114.71.198.0/24114.71.198.1 to 114.71.198.254114.71.198.255254
200114.71.199.0/24114.71.199.1 to 114.71.199.254114.71.199.255254
201114.71.200.0/24114.71.200.1 to 114.71.200.254114.71.200.255254
202114.71.201.0/24114.71.201.1 to 114.71.201.254114.71.201.255254
203114.71.202.0/24114.71.202.1 to 114.71.202.254114.71.202.255254
204114.71.203.0/24114.71.203.1 to 114.71.203.254114.71.203.255254
205114.71.204.0/24114.71.204.1 to 114.71.204.254114.71.204.255254
206114.71.205.0/24114.71.205.1 to 114.71.205.254114.71.205.255254
207114.71.206.0/24114.71.206.1 to 114.71.206.254114.71.206.255254
208114.71.207.0/24114.71.207.1 to 114.71.207.254114.71.207.255254
209114.71.208.0/24114.71.208.1 to 114.71.208.254114.71.208.255254
210114.71.209.0/24114.71.209.1 to 114.71.209.254114.71.209.255254
211114.71.210.0/24114.71.210.1 to 114.71.210.254114.71.210.255254
212114.71.211.0/24114.71.211.1 to 114.71.211.254114.71.211.255254
213114.71.212.0/24114.71.212.1 to 114.71.212.254114.71.212.255254
214114.71.213.0/24114.71.213.1 to 114.71.213.254114.71.213.255254
215114.71.214.0/24114.71.214.1 to 114.71.214.254114.71.214.255254
216114.71.215.0/24114.71.215.1 to 114.71.215.254114.71.215.255254
217114.71.216.0/24114.71.216.1 to 114.71.216.254114.71.216.255254
218114.71.217.0/24114.71.217.1 to 114.71.217.254114.71.217.255254
219114.71.218.0/24114.71.218.1 to 114.71.218.254114.71.218.255254
220114.71.219.0/24114.71.219.1 to 114.71.219.254114.71.219.255254
221114.71.220.0/24114.71.220.1 to 114.71.220.254114.71.220.255254
222114.71.221.0/24114.71.221.1 to 114.71.221.254114.71.221.255254
223114.71.222.0/24114.71.222.1 to 114.71.222.254114.71.222.255254
224114.71.223.0/24114.71.223.1 to 114.71.223.254114.71.223.255254
225114.71.224.0/24114.71.224.1 to 114.71.224.254114.71.224.255254
226114.71.225.0/24114.71.225.1 to 114.71.225.254114.71.225.255254
227114.71.226.0/24114.71.226.1 to 114.71.226.254114.71.226.255254
228114.71.227.0/24114.71.227.1 to 114.71.227.254114.71.227.255254
229114.71.228.0/24114.71.228.1 to 114.71.228.254114.71.228.255254
230114.71.229.0/24114.71.229.1 to 114.71.229.254114.71.229.255254
231114.71.230.0/24114.71.230.1 to 114.71.230.254114.71.230.255254
232114.71.231.0/24114.71.231.1 to 114.71.231.254114.71.231.255254
233114.71.232.0/24114.71.232.1 to 114.71.232.254114.71.232.255254
234114.71.233.0/24114.71.233.1 to 114.71.233.254114.71.233.255254
235114.71.234.0/24114.71.234.1 to 114.71.234.254114.71.234.255254
236114.71.235.0/24114.71.235.1 to 114.71.235.254114.71.235.255254
237114.71.236.0/24114.71.236.1 to 114.71.236.254114.71.236.255254
238114.71.237.0/24114.71.237.1 to 114.71.237.254114.71.237.255254
239114.71.238.0/24114.71.238.1 to 114.71.238.254114.71.238.255254
240114.71.239.0/24114.71.239.1 to 114.71.239.254114.71.239.255254
241114.71.240.0/24114.71.240.1 to 114.71.240.254114.71.240.255254
242114.71.241.0/24114.71.241.1 to 114.71.241.254114.71.241.255254
243114.71.242.0/24114.71.242.1 to 114.71.242.254114.71.242.255254
244114.71.243.0/24114.71.243.1 to 114.71.243.254114.71.243.255254
245114.71.244.0/24114.71.244.1 to 114.71.244.254114.71.244.255254
246114.71.245.0/24114.71.245.1 to 114.71.245.254114.71.245.255254
247114.71.246.0/24114.71.246.1 to 114.71.246.254114.71.246.255254
248114.71.247.0/24114.71.247.1 to 114.71.247.254114.71.247.255254
249114.71.248.0/24114.71.248.1 to 114.71.248.254114.71.248.255254
250114.71.249.0/24114.71.249.1 to 114.71.249.254114.71.249.255254
251114.71.250.0/24114.71.250.1 to 114.71.250.254114.71.250.255254
252114.71.251.0/24114.71.251.1 to 114.71.251.254114.71.251.255254
253114.71.252.0/24114.71.252.1 to 114.71.252.254114.71.252.255254
254114.71.253.0/24114.71.253.1 to 114.71.253.254114.71.253.255254
255114.71.254.0/24114.71.254.1 to 114.71.254.254114.71.254.255254
256114.71.255.0/24114.71.255.1 to 114.71.255.254114.71.255.255254

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

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.