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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.

Network114.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
114.0.0.0
Broadcast address
114.255.255.255
First usable
114.0.0.1
Last usable
114.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 72000000 · Integer 1912602624 to 1929379839
Reverse DNS zone
114.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110010..00000000.00000000.00000000114.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01110010..00000000.00000000.00000000114.0.0.0
Broadcast01110010..11111111.11111111.11111111114.255.255.255
Split into smaller subnets/16
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

114.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1114.0.0.0/16114.0.0.1 to 114.0.255.254114.0.255.25565,534
2114.1.0.0/16114.1.0.1 to 114.1.255.254114.1.255.25565,534
3114.2.0.0/16114.2.0.1 to 114.2.255.254114.2.255.25565,534
4114.3.0.0/16114.3.0.1 to 114.3.255.254114.3.255.25565,534
5114.4.0.0/16114.4.0.1 to 114.4.255.254114.4.255.25565,534
6114.5.0.0/16114.5.0.1 to 114.5.255.254114.5.255.25565,534
7114.6.0.0/16114.6.0.1 to 114.6.255.254114.6.255.25565,534
8114.7.0.0/16114.7.0.1 to 114.7.255.254114.7.255.25565,534
9114.8.0.0/16114.8.0.1 to 114.8.255.254114.8.255.25565,534
10114.9.0.0/16114.9.0.1 to 114.9.255.254114.9.255.25565,534
11114.10.0.0/16114.10.0.1 to 114.10.255.254114.10.255.25565,534
12114.11.0.0/16114.11.0.1 to 114.11.255.254114.11.255.25565,534
13114.12.0.0/16114.12.0.1 to 114.12.255.254114.12.255.25565,534
14114.13.0.0/16114.13.0.1 to 114.13.255.254114.13.255.25565,534
15114.14.0.0/16114.14.0.1 to 114.14.255.254114.14.255.25565,534
16114.15.0.0/16114.15.0.1 to 114.15.255.254114.15.255.25565,534
17114.16.0.0/16114.16.0.1 to 114.16.255.254114.16.255.25565,534
18114.17.0.0/16114.17.0.1 to 114.17.255.254114.17.255.25565,534
19114.18.0.0/16114.18.0.1 to 114.18.255.254114.18.255.25565,534
20114.19.0.0/16114.19.0.1 to 114.19.255.254114.19.255.25565,534
21114.20.0.0/16114.20.0.1 to 114.20.255.254114.20.255.25565,534
22114.21.0.0/16114.21.0.1 to 114.21.255.254114.21.255.25565,534
23114.22.0.0/16114.22.0.1 to 114.22.255.254114.22.255.25565,534
24114.23.0.0/16114.23.0.1 to 114.23.255.254114.23.255.25565,534
25114.24.0.0/16114.24.0.1 to 114.24.255.254114.24.255.25565,534
26114.25.0.0/16114.25.0.1 to 114.25.255.254114.25.255.25565,534
27114.26.0.0/16114.26.0.1 to 114.26.255.254114.26.255.25565,534
28114.27.0.0/16114.27.0.1 to 114.27.255.254114.27.255.25565,534
29114.28.0.0/16114.28.0.1 to 114.28.255.254114.28.255.25565,534
30114.29.0.0/16114.29.0.1 to 114.29.255.254114.29.255.25565,534
31114.30.0.0/16114.30.0.1 to 114.30.255.254114.30.255.25565,534
32114.31.0.0/16114.31.0.1 to 114.31.255.254114.31.255.25565,534
33114.32.0.0/16114.32.0.1 to 114.32.255.254114.32.255.25565,534
34114.33.0.0/16114.33.0.1 to 114.33.255.254114.33.255.25565,534
35114.34.0.0/16114.34.0.1 to 114.34.255.254114.34.255.25565,534
36114.35.0.0/16114.35.0.1 to 114.35.255.254114.35.255.25565,534
37114.36.0.0/16114.36.0.1 to 114.36.255.254114.36.255.25565,534
38114.37.0.0/16114.37.0.1 to 114.37.255.254114.37.255.25565,534
39114.38.0.0/16114.38.0.1 to 114.38.255.254114.38.255.25565,534
40114.39.0.0/16114.39.0.1 to 114.39.255.254114.39.255.25565,534
41114.40.0.0/16114.40.0.1 to 114.40.255.254114.40.255.25565,534
42114.41.0.0/16114.41.0.1 to 114.41.255.254114.41.255.25565,534
43114.42.0.0/16114.42.0.1 to 114.42.255.254114.42.255.25565,534
44114.43.0.0/16114.43.0.1 to 114.43.255.254114.43.255.25565,534
45114.44.0.0/16114.44.0.1 to 114.44.255.254114.44.255.25565,534
46114.45.0.0/16114.45.0.1 to 114.45.255.254114.45.255.25565,534
47114.46.0.0/16114.46.0.1 to 114.46.255.254114.46.255.25565,534
48114.47.0.0/16114.47.0.1 to 114.47.255.254114.47.255.25565,534
49114.48.0.0/16114.48.0.1 to 114.48.255.254114.48.255.25565,534
50114.49.0.0/16114.49.0.1 to 114.49.255.254114.49.255.25565,534
51114.50.0.0/16114.50.0.1 to 114.50.255.254114.50.255.25565,534
52114.51.0.0/16114.51.0.1 to 114.51.255.254114.51.255.25565,534
53114.52.0.0/16114.52.0.1 to 114.52.255.254114.52.255.25565,534
54114.53.0.0/16114.53.0.1 to 114.53.255.254114.53.255.25565,534
55114.54.0.0/16114.54.0.1 to 114.54.255.254114.54.255.25565,534
56114.55.0.0/16114.55.0.1 to 114.55.255.254114.55.255.25565,534
57114.56.0.0/16114.56.0.1 to 114.56.255.254114.56.255.25565,534
58114.57.0.0/16114.57.0.1 to 114.57.255.254114.57.255.25565,534
59114.58.0.0/16114.58.0.1 to 114.58.255.254114.58.255.25565,534
60114.59.0.0/16114.59.0.1 to 114.59.255.254114.59.255.25565,534
61114.60.0.0/16114.60.0.1 to 114.60.255.254114.60.255.25565,534
62114.61.0.0/16114.61.0.1 to 114.61.255.254114.61.255.25565,534
63114.62.0.0/16114.62.0.1 to 114.62.255.254114.62.255.25565,534
64114.63.0.0/16114.63.0.1 to 114.63.255.254114.63.255.25565,534
65114.64.0.0/16114.64.0.1 to 114.64.255.254114.64.255.25565,534
66114.65.0.0/16114.65.0.1 to 114.65.255.254114.65.255.25565,534
67114.66.0.0/16114.66.0.1 to 114.66.255.254114.66.255.25565,534
68114.67.0.0/16114.67.0.1 to 114.67.255.254114.67.255.25565,534
69114.68.0.0/16114.68.0.1 to 114.68.255.254114.68.255.25565,534
70114.69.0.0/16114.69.0.1 to 114.69.255.254114.69.255.25565,534
71114.70.0.0/16114.70.0.1 to 114.70.255.254114.70.255.25565,534
72114.71.0.0/16114.71.0.1 to 114.71.255.254114.71.255.25565,534
73114.72.0.0/16114.72.0.1 to 114.72.255.254114.72.255.25565,534
74114.73.0.0/16114.73.0.1 to 114.73.255.254114.73.255.25565,534
75114.74.0.0/16114.74.0.1 to 114.74.255.254114.74.255.25565,534
76114.75.0.0/16114.75.0.1 to 114.75.255.254114.75.255.25565,534
77114.76.0.0/16114.76.0.1 to 114.76.255.254114.76.255.25565,534
78114.77.0.0/16114.77.0.1 to 114.77.255.254114.77.255.25565,534
79114.78.0.0/16114.78.0.1 to 114.78.255.254114.78.255.25565,534
80114.79.0.0/16114.79.0.1 to 114.79.255.254114.79.255.25565,534
81114.80.0.0/16114.80.0.1 to 114.80.255.254114.80.255.25565,534
82114.81.0.0/16114.81.0.1 to 114.81.255.254114.81.255.25565,534
83114.82.0.0/16114.82.0.1 to 114.82.255.254114.82.255.25565,534
84114.83.0.0/16114.83.0.1 to 114.83.255.254114.83.255.25565,534
85114.84.0.0/16114.84.0.1 to 114.84.255.254114.84.255.25565,534
86114.85.0.0/16114.85.0.1 to 114.85.255.254114.85.255.25565,534
87114.86.0.0/16114.86.0.1 to 114.86.255.254114.86.255.25565,534
88114.87.0.0/16114.87.0.1 to 114.87.255.254114.87.255.25565,534
89114.88.0.0/16114.88.0.1 to 114.88.255.254114.88.255.25565,534
90114.89.0.0/16114.89.0.1 to 114.89.255.254114.89.255.25565,534
91114.90.0.0/16114.90.0.1 to 114.90.255.254114.90.255.25565,534
92114.91.0.0/16114.91.0.1 to 114.91.255.254114.91.255.25565,534
93114.92.0.0/16114.92.0.1 to 114.92.255.254114.92.255.25565,534
94114.93.0.0/16114.93.0.1 to 114.93.255.254114.93.255.25565,534
95114.94.0.0/16114.94.0.1 to 114.94.255.254114.94.255.25565,534
96114.95.0.0/16114.95.0.1 to 114.95.255.254114.95.255.25565,534
97114.96.0.0/16114.96.0.1 to 114.96.255.254114.96.255.25565,534
98114.97.0.0/16114.97.0.1 to 114.97.255.254114.97.255.25565,534
99114.98.0.0/16114.98.0.1 to 114.98.255.254114.98.255.25565,534
100114.99.0.0/16114.99.0.1 to 114.99.255.254114.99.255.25565,534
101114.100.0.0/16114.100.0.1 to 114.100.255.254114.100.255.25565,534
102114.101.0.0/16114.101.0.1 to 114.101.255.254114.101.255.25565,534
103114.102.0.0/16114.102.0.1 to 114.102.255.254114.102.255.25565,534
104114.103.0.0/16114.103.0.1 to 114.103.255.254114.103.255.25565,534
105114.104.0.0/16114.104.0.1 to 114.104.255.254114.104.255.25565,534
106114.105.0.0/16114.105.0.1 to 114.105.255.254114.105.255.25565,534
107114.106.0.0/16114.106.0.1 to 114.106.255.254114.106.255.25565,534
108114.107.0.0/16114.107.0.1 to 114.107.255.254114.107.255.25565,534
109114.108.0.0/16114.108.0.1 to 114.108.255.254114.108.255.25565,534
110114.109.0.0/16114.109.0.1 to 114.109.255.254114.109.255.25565,534
111114.110.0.0/16114.110.0.1 to 114.110.255.254114.110.255.25565,534
112114.111.0.0/16114.111.0.1 to 114.111.255.254114.111.255.25565,534
113114.112.0.0/16114.112.0.1 to 114.112.255.254114.112.255.25565,534
114114.113.0.0/16114.113.0.1 to 114.113.255.254114.113.255.25565,534
115114.114.0.0/16114.114.0.1 to 114.114.255.254114.114.255.25565,534
116114.115.0.0/16114.115.0.1 to 114.115.255.254114.115.255.25565,534
117114.116.0.0/16114.116.0.1 to 114.116.255.254114.116.255.25565,534
118114.117.0.0/16114.117.0.1 to 114.117.255.254114.117.255.25565,534
119114.118.0.0/16114.118.0.1 to 114.118.255.254114.118.255.25565,534
120114.119.0.0/16114.119.0.1 to 114.119.255.254114.119.255.25565,534
121114.120.0.0/16114.120.0.1 to 114.120.255.254114.120.255.25565,534
122114.121.0.0/16114.121.0.1 to 114.121.255.254114.121.255.25565,534
123114.122.0.0/16114.122.0.1 to 114.122.255.254114.122.255.25565,534
124114.123.0.0/16114.123.0.1 to 114.123.255.254114.123.255.25565,534
125114.124.0.0/16114.124.0.1 to 114.124.255.254114.124.255.25565,534
126114.125.0.0/16114.125.0.1 to 114.125.255.254114.125.255.25565,534
127114.126.0.0/16114.126.0.1 to 114.126.255.254114.126.255.25565,534
128114.127.0.0/16114.127.0.1 to 114.127.255.254114.127.255.25565,534
129114.128.0.0/16114.128.0.1 to 114.128.255.254114.128.255.25565,534
130114.129.0.0/16114.129.0.1 to 114.129.255.254114.129.255.25565,534
131114.130.0.0/16114.130.0.1 to 114.130.255.254114.130.255.25565,534
132114.131.0.0/16114.131.0.1 to 114.131.255.254114.131.255.25565,534
133114.132.0.0/16114.132.0.1 to 114.132.255.254114.132.255.25565,534
134114.133.0.0/16114.133.0.1 to 114.133.255.254114.133.255.25565,534
135114.134.0.0/16114.134.0.1 to 114.134.255.254114.134.255.25565,534
136114.135.0.0/16114.135.0.1 to 114.135.255.254114.135.255.25565,534
137114.136.0.0/16114.136.0.1 to 114.136.255.254114.136.255.25565,534
138114.137.0.0/16114.137.0.1 to 114.137.255.254114.137.255.25565,534
139114.138.0.0/16114.138.0.1 to 114.138.255.254114.138.255.25565,534
140114.139.0.0/16114.139.0.1 to 114.139.255.254114.139.255.25565,534
141114.140.0.0/16114.140.0.1 to 114.140.255.254114.140.255.25565,534
142114.141.0.0/16114.141.0.1 to 114.141.255.254114.141.255.25565,534
143114.142.0.0/16114.142.0.1 to 114.142.255.254114.142.255.25565,534
144114.143.0.0/16114.143.0.1 to 114.143.255.254114.143.255.25565,534
145114.144.0.0/16114.144.0.1 to 114.144.255.254114.144.255.25565,534
146114.145.0.0/16114.145.0.1 to 114.145.255.254114.145.255.25565,534
147114.146.0.0/16114.146.0.1 to 114.146.255.254114.146.255.25565,534
148114.147.0.0/16114.147.0.1 to 114.147.255.254114.147.255.25565,534
149114.148.0.0/16114.148.0.1 to 114.148.255.254114.148.255.25565,534
150114.149.0.0/16114.149.0.1 to 114.149.255.254114.149.255.25565,534
151114.150.0.0/16114.150.0.1 to 114.150.255.254114.150.255.25565,534
152114.151.0.0/16114.151.0.1 to 114.151.255.254114.151.255.25565,534
153114.152.0.0/16114.152.0.1 to 114.152.255.254114.152.255.25565,534
154114.153.0.0/16114.153.0.1 to 114.153.255.254114.153.255.25565,534
155114.154.0.0/16114.154.0.1 to 114.154.255.254114.154.255.25565,534
156114.155.0.0/16114.155.0.1 to 114.155.255.254114.155.255.25565,534
157114.156.0.0/16114.156.0.1 to 114.156.255.254114.156.255.25565,534
158114.157.0.0/16114.157.0.1 to 114.157.255.254114.157.255.25565,534
159114.158.0.0/16114.158.0.1 to 114.158.255.254114.158.255.25565,534
160114.159.0.0/16114.159.0.1 to 114.159.255.254114.159.255.25565,534
161114.160.0.0/16114.160.0.1 to 114.160.255.254114.160.255.25565,534
162114.161.0.0/16114.161.0.1 to 114.161.255.254114.161.255.25565,534
163114.162.0.0/16114.162.0.1 to 114.162.255.254114.162.255.25565,534
164114.163.0.0/16114.163.0.1 to 114.163.255.254114.163.255.25565,534
165114.164.0.0/16114.164.0.1 to 114.164.255.254114.164.255.25565,534
166114.165.0.0/16114.165.0.1 to 114.165.255.254114.165.255.25565,534
167114.166.0.0/16114.166.0.1 to 114.166.255.254114.166.255.25565,534
168114.167.0.0/16114.167.0.1 to 114.167.255.254114.167.255.25565,534
169114.168.0.0/16114.168.0.1 to 114.168.255.254114.168.255.25565,534
170114.169.0.0/16114.169.0.1 to 114.169.255.254114.169.255.25565,534
171114.170.0.0/16114.170.0.1 to 114.170.255.254114.170.255.25565,534
172114.171.0.0/16114.171.0.1 to 114.171.255.254114.171.255.25565,534
173114.172.0.0/16114.172.0.1 to 114.172.255.254114.172.255.25565,534
174114.173.0.0/16114.173.0.1 to 114.173.255.254114.173.255.25565,534
175114.174.0.0/16114.174.0.1 to 114.174.255.254114.174.255.25565,534
176114.175.0.0/16114.175.0.1 to 114.175.255.254114.175.255.25565,534
177114.176.0.0/16114.176.0.1 to 114.176.255.254114.176.255.25565,534
178114.177.0.0/16114.177.0.1 to 114.177.255.254114.177.255.25565,534
179114.178.0.0/16114.178.0.1 to 114.178.255.254114.178.255.25565,534
180114.179.0.0/16114.179.0.1 to 114.179.255.254114.179.255.25565,534
181114.180.0.0/16114.180.0.1 to 114.180.255.254114.180.255.25565,534
182114.181.0.0/16114.181.0.1 to 114.181.255.254114.181.255.25565,534
183114.182.0.0/16114.182.0.1 to 114.182.255.254114.182.255.25565,534
184114.183.0.0/16114.183.0.1 to 114.183.255.254114.183.255.25565,534
185114.184.0.0/16114.184.0.1 to 114.184.255.254114.184.255.25565,534
186114.185.0.0/16114.185.0.1 to 114.185.255.254114.185.255.25565,534
187114.186.0.0/16114.186.0.1 to 114.186.255.254114.186.255.25565,534
188114.187.0.0/16114.187.0.1 to 114.187.255.254114.187.255.25565,534
189114.188.0.0/16114.188.0.1 to 114.188.255.254114.188.255.25565,534
190114.189.0.0/16114.189.0.1 to 114.189.255.254114.189.255.25565,534
191114.190.0.0/16114.190.0.1 to 114.190.255.254114.190.255.25565,534
192114.191.0.0/16114.191.0.1 to 114.191.255.254114.191.255.25565,534
193114.192.0.0/16114.192.0.1 to 114.192.255.254114.192.255.25565,534
194114.193.0.0/16114.193.0.1 to 114.193.255.254114.193.255.25565,534
195114.194.0.0/16114.194.0.1 to 114.194.255.254114.194.255.25565,534
196114.195.0.0/16114.195.0.1 to 114.195.255.254114.195.255.25565,534
197114.196.0.0/16114.196.0.1 to 114.196.255.254114.196.255.25565,534
198114.197.0.0/16114.197.0.1 to 114.197.255.254114.197.255.25565,534
199114.198.0.0/16114.198.0.1 to 114.198.255.254114.198.255.25565,534
200114.199.0.0/16114.199.0.1 to 114.199.255.254114.199.255.25565,534
201114.200.0.0/16114.200.0.1 to 114.200.255.254114.200.255.25565,534
202114.201.0.0/16114.201.0.1 to 114.201.255.254114.201.255.25565,534
203114.202.0.0/16114.202.0.1 to 114.202.255.254114.202.255.25565,534
204114.203.0.0/16114.203.0.1 to 114.203.255.254114.203.255.25565,534
205114.204.0.0/16114.204.0.1 to 114.204.255.254114.204.255.25565,534
206114.205.0.0/16114.205.0.1 to 114.205.255.254114.205.255.25565,534
207114.206.0.0/16114.206.0.1 to 114.206.255.254114.206.255.25565,534
208114.207.0.0/16114.207.0.1 to 114.207.255.254114.207.255.25565,534
209114.208.0.0/16114.208.0.1 to 114.208.255.254114.208.255.25565,534
210114.209.0.0/16114.209.0.1 to 114.209.255.254114.209.255.25565,534
211114.210.0.0/16114.210.0.1 to 114.210.255.254114.210.255.25565,534
212114.211.0.0/16114.211.0.1 to 114.211.255.254114.211.255.25565,534
213114.212.0.0/16114.212.0.1 to 114.212.255.254114.212.255.25565,534
214114.213.0.0/16114.213.0.1 to 114.213.255.254114.213.255.25565,534
215114.214.0.0/16114.214.0.1 to 114.214.255.254114.214.255.25565,534
216114.215.0.0/16114.215.0.1 to 114.215.255.254114.215.255.25565,534
217114.216.0.0/16114.216.0.1 to 114.216.255.254114.216.255.25565,534
218114.217.0.0/16114.217.0.1 to 114.217.255.254114.217.255.25565,534
219114.218.0.0/16114.218.0.1 to 114.218.255.254114.218.255.25565,534
220114.219.0.0/16114.219.0.1 to 114.219.255.254114.219.255.25565,534
221114.220.0.0/16114.220.0.1 to 114.220.255.254114.220.255.25565,534
222114.221.0.0/16114.221.0.1 to 114.221.255.254114.221.255.25565,534
223114.222.0.0/16114.222.0.1 to 114.222.255.254114.222.255.25565,534
224114.223.0.0/16114.223.0.1 to 114.223.255.254114.223.255.25565,534
225114.224.0.0/16114.224.0.1 to 114.224.255.254114.224.255.25565,534
226114.225.0.0/16114.225.0.1 to 114.225.255.254114.225.255.25565,534
227114.226.0.0/16114.226.0.1 to 114.226.255.254114.226.255.25565,534
228114.227.0.0/16114.227.0.1 to 114.227.255.254114.227.255.25565,534
229114.228.0.0/16114.228.0.1 to 114.228.255.254114.228.255.25565,534
230114.229.0.0/16114.229.0.1 to 114.229.255.254114.229.255.25565,534
231114.230.0.0/16114.230.0.1 to 114.230.255.254114.230.255.25565,534
232114.231.0.0/16114.231.0.1 to 114.231.255.254114.231.255.25565,534
233114.232.0.0/16114.232.0.1 to 114.232.255.254114.232.255.25565,534
234114.233.0.0/16114.233.0.1 to 114.233.255.254114.233.255.25565,534
235114.234.0.0/16114.234.0.1 to 114.234.255.254114.234.255.25565,534
236114.235.0.0/16114.235.0.1 to 114.235.255.254114.235.255.25565,534
237114.236.0.0/16114.236.0.1 to 114.236.255.254114.236.255.25565,534
238114.237.0.0/16114.237.0.1 to 114.237.255.254114.237.255.25565,534
239114.238.0.0/16114.238.0.1 to 114.238.255.254114.238.255.25565,534
240114.239.0.0/16114.239.0.1 to 114.239.255.254114.239.255.25565,534
241114.240.0.0/16114.240.0.1 to 114.240.255.254114.240.255.25565,534
242114.241.0.0/16114.241.0.1 to 114.241.255.254114.241.255.25565,534
243114.242.0.0/16114.242.0.1 to 114.242.255.254114.242.255.25565,534
244114.243.0.0/16114.243.0.1 to 114.243.255.254114.243.255.25565,534
245114.244.0.0/16114.244.0.1 to 114.244.255.254114.244.255.25565,534
246114.245.0.0/16114.245.0.1 to 114.245.255.254114.245.255.25565,534
247114.246.0.0/16114.246.0.1 to 114.246.255.254114.246.255.25565,534
248114.247.0.0/16114.247.0.1 to 114.247.255.254114.247.255.25565,534
249114.248.0.0/16114.248.0.1 to 114.248.255.254114.248.255.25565,534
250114.249.0.0/16114.249.0.1 to 114.249.255.254114.249.255.25565,534
251114.250.0.0/16114.250.0.1 to 114.250.255.254114.250.255.25565,534
252114.251.0.0/16114.251.0.1 to 114.251.255.254114.251.255.25565,534
253114.252.0.0/16114.252.0.1 to 114.252.255.254114.252.255.25565,534
254114.253.0.0/16114.253.0.1 to 114.253.255.254114.253.255.25565,534
255114.254.0.0/16114.254.0.1 to 114.254.255.254114.254.255.25565,534
256114.255.0.0/16114.255.0.1 to 114.255.255.254114.255.255.25565,534

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.