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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.

Network140.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
140.0.0.0
Broadcast address
140.255.255.255
First usable
140.0.0.1
Last usable
140.255.255.254
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
B (default /16)
As numbers
Hex 8C000000 · Integer 2348810240 to 2365587455
Reverse DNS zone
140.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10001100..00000000.00000000.00000000140.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10001100..00000000.00000000.00000000140.0.0.0
Broadcast10001100..11111111.11111111.11111111140.255.255.255
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)

140.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1140.0.0.0/16140.0.0.1 to 140.0.255.254140.0.255.25565,534
2140.1.0.0/16140.1.0.1 to 140.1.255.254140.1.255.25565,534
3140.2.0.0/16140.2.0.1 to 140.2.255.254140.2.255.25565,534
4140.3.0.0/16140.3.0.1 to 140.3.255.254140.3.255.25565,534
5140.4.0.0/16140.4.0.1 to 140.4.255.254140.4.255.25565,534
6140.5.0.0/16140.5.0.1 to 140.5.255.254140.5.255.25565,534
7140.6.0.0/16140.6.0.1 to 140.6.255.254140.6.255.25565,534
8140.7.0.0/16140.7.0.1 to 140.7.255.254140.7.255.25565,534
9140.8.0.0/16140.8.0.1 to 140.8.255.254140.8.255.25565,534
10140.9.0.0/16140.9.0.1 to 140.9.255.254140.9.255.25565,534
11140.10.0.0/16140.10.0.1 to 140.10.255.254140.10.255.25565,534
12140.11.0.0/16140.11.0.1 to 140.11.255.254140.11.255.25565,534
13140.12.0.0/16140.12.0.1 to 140.12.255.254140.12.255.25565,534
14140.13.0.0/16140.13.0.1 to 140.13.255.254140.13.255.25565,534
15140.14.0.0/16140.14.0.1 to 140.14.255.254140.14.255.25565,534
16140.15.0.0/16140.15.0.1 to 140.15.255.254140.15.255.25565,534
17140.16.0.0/16140.16.0.1 to 140.16.255.254140.16.255.25565,534
18140.17.0.0/16140.17.0.1 to 140.17.255.254140.17.255.25565,534
19140.18.0.0/16140.18.0.1 to 140.18.255.254140.18.255.25565,534
20140.19.0.0/16140.19.0.1 to 140.19.255.254140.19.255.25565,534
21140.20.0.0/16140.20.0.1 to 140.20.255.254140.20.255.25565,534
22140.21.0.0/16140.21.0.1 to 140.21.255.254140.21.255.25565,534
23140.22.0.0/16140.22.0.1 to 140.22.255.254140.22.255.25565,534
24140.23.0.0/16140.23.0.1 to 140.23.255.254140.23.255.25565,534
25140.24.0.0/16140.24.0.1 to 140.24.255.254140.24.255.25565,534
26140.25.0.0/16140.25.0.1 to 140.25.255.254140.25.255.25565,534
27140.26.0.0/16140.26.0.1 to 140.26.255.254140.26.255.25565,534
28140.27.0.0/16140.27.0.1 to 140.27.255.254140.27.255.25565,534
29140.28.0.0/16140.28.0.1 to 140.28.255.254140.28.255.25565,534
30140.29.0.0/16140.29.0.1 to 140.29.255.254140.29.255.25565,534
31140.30.0.0/16140.30.0.1 to 140.30.255.254140.30.255.25565,534
32140.31.0.0/16140.31.0.1 to 140.31.255.254140.31.255.25565,534
33140.32.0.0/16140.32.0.1 to 140.32.255.254140.32.255.25565,534
34140.33.0.0/16140.33.0.1 to 140.33.255.254140.33.255.25565,534
35140.34.0.0/16140.34.0.1 to 140.34.255.254140.34.255.25565,534
36140.35.0.0/16140.35.0.1 to 140.35.255.254140.35.255.25565,534
37140.36.0.0/16140.36.0.1 to 140.36.255.254140.36.255.25565,534
38140.37.0.0/16140.37.0.1 to 140.37.255.254140.37.255.25565,534
39140.38.0.0/16140.38.0.1 to 140.38.255.254140.38.255.25565,534
40140.39.0.0/16140.39.0.1 to 140.39.255.254140.39.255.25565,534
41140.40.0.0/16140.40.0.1 to 140.40.255.254140.40.255.25565,534
42140.41.0.0/16140.41.0.1 to 140.41.255.254140.41.255.25565,534
43140.42.0.0/16140.42.0.1 to 140.42.255.254140.42.255.25565,534
44140.43.0.0/16140.43.0.1 to 140.43.255.254140.43.255.25565,534
45140.44.0.0/16140.44.0.1 to 140.44.255.254140.44.255.25565,534
46140.45.0.0/16140.45.0.1 to 140.45.255.254140.45.255.25565,534
47140.46.0.0/16140.46.0.1 to 140.46.255.254140.46.255.25565,534
48140.47.0.0/16140.47.0.1 to 140.47.255.254140.47.255.25565,534
49140.48.0.0/16140.48.0.1 to 140.48.255.254140.48.255.25565,534
50140.49.0.0/16140.49.0.1 to 140.49.255.254140.49.255.25565,534
51140.50.0.0/16140.50.0.1 to 140.50.255.254140.50.255.25565,534
52140.51.0.0/16140.51.0.1 to 140.51.255.254140.51.255.25565,534
53140.52.0.0/16140.52.0.1 to 140.52.255.254140.52.255.25565,534
54140.53.0.0/16140.53.0.1 to 140.53.255.254140.53.255.25565,534
55140.54.0.0/16140.54.0.1 to 140.54.255.254140.54.255.25565,534
56140.55.0.0/16140.55.0.1 to 140.55.255.254140.55.255.25565,534
57140.56.0.0/16140.56.0.1 to 140.56.255.254140.56.255.25565,534
58140.57.0.0/16140.57.0.1 to 140.57.255.254140.57.255.25565,534
59140.58.0.0/16140.58.0.1 to 140.58.255.254140.58.255.25565,534
60140.59.0.0/16140.59.0.1 to 140.59.255.254140.59.255.25565,534
61140.60.0.0/16140.60.0.1 to 140.60.255.254140.60.255.25565,534
62140.61.0.0/16140.61.0.1 to 140.61.255.254140.61.255.25565,534
63140.62.0.0/16140.62.0.1 to 140.62.255.254140.62.255.25565,534
64140.63.0.0/16140.63.0.1 to 140.63.255.254140.63.255.25565,534
65140.64.0.0/16140.64.0.1 to 140.64.255.254140.64.255.25565,534
66140.65.0.0/16140.65.0.1 to 140.65.255.254140.65.255.25565,534
67140.66.0.0/16140.66.0.1 to 140.66.255.254140.66.255.25565,534
68140.67.0.0/16140.67.0.1 to 140.67.255.254140.67.255.25565,534
69140.68.0.0/16140.68.0.1 to 140.68.255.254140.68.255.25565,534
70140.69.0.0/16140.69.0.1 to 140.69.255.254140.69.255.25565,534
71140.70.0.0/16140.70.0.1 to 140.70.255.254140.70.255.25565,534
72140.71.0.0/16140.71.0.1 to 140.71.255.254140.71.255.25565,534
73140.72.0.0/16140.72.0.1 to 140.72.255.254140.72.255.25565,534
74140.73.0.0/16140.73.0.1 to 140.73.255.254140.73.255.25565,534
75140.74.0.0/16140.74.0.1 to 140.74.255.254140.74.255.25565,534
76140.75.0.0/16140.75.0.1 to 140.75.255.254140.75.255.25565,534
77140.76.0.0/16140.76.0.1 to 140.76.255.254140.76.255.25565,534
78140.77.0.0/16140.77.0.1 to 140.77.255.254140.77.255.25565,534
79140.78.0.0/16140.78.0.1 to 140.78.255.254140.78.255.25565,534
80140.79.0.0/16140.79.0.1 to 140.79.255.254140.79.255.25565,534
81140.80.0.0/16140.80.0.1 to 140.80.255.254140.80.255.25565,534
82140.81.0.0/16140.81.0.1 to 140.81.255.254140.81.255.25565,534
83140.82.0.0/16140.82.0.1 to 140.82.255.254140.82.255.25565,534
84140.83.0.0/16140.83.0.1 to 140.83.255.254140.83.255.25565,534
85140.84.0.0/16140.84.0.1 to 140.84.255.254140.84.255.25565,534
86140.85.0.0/16140.85.0.1 to 140.85.255.254140.85.255.25565,534
87140.86.0.0/16140.86.0.1 to 140.86.255.254140.86.255.25565,534
88140.87.0.0/16140.87.0.1 to 140.87.255.254140.87.255.25565,534
89140.88.0.0/16140.88.0.1 to 140.88.255.254140.88.255.25565,534
90140.89.0.0/16140.89.0.1 to 140.89.255.254140.89.255.25565,534
91140.90.0.0/16140.90.0.1 to 140.90.255.254140.90.255.25565,534
92140.91.0.0/16140.91.0.1 to 140.91.255.254140.91.255.25565,534
93140.92.0.0/16140.92.0.1 to 140.92.255.254140.92.255.25565,534
94140.93.0.0/16140.93.0.1 to 140.93.255.254140.93.255.25565,534
95140.94.0.0/16140.94.0.1 to 140.94.255.254140.94.255.25565,534
96140.95.0.0/16140.95.0.1 to 140.95.255.254140.95.255.25565,534
97140.96.0.0/16140.96.0.1 to 140.96.255.254140.96.255.25565,534
98140.97.0.0/16140.97.0.1 to 140.97.255.254140.97.255.25565,534
99140.98.0.0/16140.98.0.1 to 140.98.255.254140.98.255.25565,534
100140.99.0.0/16140.99.0.1 to 140.99.255.254140.99.255.25565,534
101140.100.0.0/16140.100.0.1 to 140.100.255.254140.100.255.25565,534
102140.101.0.0/16140.101.0.1 to 140.101.255.254140.101.255.25565,534
103140.102.0.0/16140.102.0.1 to 140.102.255.254140.102.255.25565,534
104140.103.0.0/16140.103.0.1 to 140.103.255.254140.103.255.25565,534
105140.104.0.0/16140.104.0.1 to 140.104.255.254140.104.255.25565,534
106140.105.0.0/16140.105.0.1 to 140.105.255.254140.105.255.25565,534
107140.106.0.0/16140.106.0.1 to 140.106.255.254140.106.255.25565,534
108140.107.0.0/16140.107.0.1 to 140.107.255.254140.107.255.25565,534
109140.108.0.0/16140.108.0.1 to 140.108.255.254140.108.255.25565,534
110140.109.0.0/16140.109.0.1 to 140.109.255.254140.109.255.25565,534
111140.110.0.0/16140.110.0.1 to 140.110.255.254140.110.255.25565,534
112140.111.0.0/16140.111.0.1 to 140.111.255.254140.111.255.25565,534
113140.112.0.0/16140.112.0.1 to 140.112.255.254140.112.255.25565,534
114140.113.0.0/16140.113.0.1 to 140.113.255.254140.113.255.25565,534
115140.114.0.0/16140.114.0.1 to 140.114.255.254140.114.255.25565,534
116140.115.0.0/16140.115.0.1 to 140.115.255.254140.115.255.25565,534
117140.116.0.0/16140.116.0.1 to 140.116.255.254140.116.255.25565,534
118140.117.0.0/16140.117.0.1 to 140.117.255.254140.117.255.25565,534
119140.118.0.0/16140.118.0.1 to 140.118.255.254140.118.255.25565,534
120140.119.0.0/16140.119.0.1 to 140.119.255.254140.119.255.25565,534
121140.120.0.0/16140.120.0.1 to 140.120.255.254140.120.255.25565,534
122140.121.0.0/16140.121.0.1 to 140.121.255.254140.121.255.25565,534
123140.122.0.0/16140.122.0.1 to 140.122.255.254140.122.255.25565,534
124140.123.0.0/16140.123.0.1 to 140.123.255.254140.123.255.25565,534
125140.124.0.0/16140.124.0.1 to 140.124.255.254140.124.255.25565,534
126140.125.0.0/16140.125.0.1 to 140.125.255.254140.125.255.25565,534
127140.126.0.0/16140.126.0.1 to 140.126.255.254140.126.255.25565,534
128140.127.0.0/16140.127.0.1 to 140.127.255.254140.127.255.25565,534
129140.128.0.0/16140.128.0.1 to 140.128.255.254140.128.255.25565,534
130140.129.0.0/16140.129.0.1 to 140.129.255.254140.129.255.25565,534
131140.130.0.0/16140.130.0.1 to 140.130.255.254140.130.255.25565,534
132140.131.0.0/16140.131.0.1 to 140.131.255.254140.131.255.25565,534
133140.132.0.0/16140.132.0.1 to 140.132.255.254140.132.255.25565,534
134140.133.0.0/16140.133.0.1 to 140.133.255.254140.133.255.25565,534
135140.134.0.0/16140.134.0.1 to 140.134.255.254140.134.255.25565,534
136140.135.0.0/16140.135.0.1 to 140.135.255.254140.135.255.25565,534
137140.136.0.0/16140.136.0.1 to 140.136.255.254140.136.255.25565,534
138140.137.0.0/16140.137.0.1 to 140.137.255.254140.137.255.25565,534
139140.138.0.0/16140.138.0.1 to 140.138.255.254140.138.255.25565,534
140140.139.0.0/16140.139.0.1 to 140.139.255.254140.139.255.25565,534
141140.140.0.0/16140.140.0.1 to 140.140.255.254140.140.255.25565,534
142140.141.0.0/16140.141.0.1 to 140.141.255.254140.141.255.25565,534
143140.142.0.0/16140.142.0.1 to 140.142.255.254140.142.255.25565,534
144140.143.0.0/16140.143.0.1 to 140.143.255.254140.143.255.25565,534
145140.144.0.0/16140.144.0.1 to 140.144.255.254140.144.255.25565,534
146140.145.0.0/16140.145.0.1 to 140.145.255.254140.145.255.25565,534
147140.146.0.0/16140.146.0.1 to 140.146.255.254140.146.255.25565,534
148140.147.0.0/16140.147.0.1 to 140.147.255.254140.147.255.25565,534
149140.148.0.0/16140.148.0.1 to 140.148.255.254140.148.255.25565,534
150140.149.0.0/16140.149.0.1 to 140.149.255.254140.149.255.25565,534
151140.150.0.0/16140.150.0.1 to 140.150.255.254140.150.255.25565,534
152140.151.0.0/16140.151.0.1 to 140.151.255.254140.151.255.25565,534
153140.152.0.0/16140.152.0.1 to 140.152.255.254140.152.255.25565,534
154140.153.0.0/16140.153.0.1 to 140.153.255.254140.153.255.25565,534
155140.154.0.0/16140.154.0.1 to 140.154.255.254140.154.255.25565,534
156140.155.0.0/16140.155.0.1 to 140.155.255.254140.155.255.25565,534
157140.156.0.0/16140.156.0.1 to 140.156.255.254140.156.255.25565,534
158140.157.0.0/16140.157.0.1 to 140.157.255.254140.157.255.25565,534
159140.158.0.0/16140.158.0.1 to 140.158.255.254140.158.255.25565,534
160140.159.0.0/16140.159.0.1 to 140.159.255.254140.159.255.25565,534
161140.160.0.0/16140.160.0.1 to 140.160.255.254140.160.255.25565,534
162140.161.0.0/16140.161.0.1 to 140.161.255.254140.161.255.25565,534
163140.162.0.0/16140.162.0.1 to 140.162.255.254140.162.255.25565,534
164140.163.0.0/16140.163.0.1 to 140.163.255.254140.163.255.25565,534
165140.164.0.0/16140.164.0.1 to 140.164.255.254140.164.255.25565,534
166140.165.0.0/16140.165.0.1 to 140.165.255.254140.165.255.25565,534
167140.166.0.0/16140.166.0.1 to 140.166.255.254140.166.255.25565,534
168140.167.0.0/16140.167.0.1 to 140.167.255.254140.167.255.25565,534
169140.168.0.0/16140.168.0.1 to 140.168.255.254140.168.255.25565,534
170140.169.0.0/16140.169.0.1 to 140.169.255.254140.169.255.25565,534
171140.170.0.0/16140.170.0.1 to 140.170.255.254140.170.255.25565,534
172140.171.0.0/16140.171.0.1 to 140.171.255.254140.171.255.25565,534
173140.172.0.0/16140.172.0.1 to 140.172.255.254140.172.255.25565,534
174140.173.0.0/16140.173.0.1 to 140.173.255.254140.173.255.25565,534
175140.174.0.0/16140.174.0.1 to 140.174.255.254140.174.255.25565,534
176140.175.0.0/16140.175.0.1 to 140.175.255.254140.175.255.25565,534
177140.176.0.0/16140.176.0.1 to 140.176.255.254140.176.255.25565,534
178140.177.0.0/16140.177.0.1 to 140.177.255.254140.177.255.25565,534
179140.178.0.0/16140.178.0.1 to 140.178.255.254140.178.255.25565,534
180140.179.0.0/16140.179.0.1 to 140.179.255.254140.179.255.25565,534
181140.180.0.0/16140.180.0.1 to 140.180.255.254140.180.255.25565,534
182140.181.0.0/16140.181.0.1 to 140.181.255.254140.181.255.25565,534
183140.182.0.0/16140.182.0.1 to 140.182.255.254140.182.255.25565,534
184140.183.0.0/16140.183.0.1 to 140.183.255.254140.183.255.25565,534
185140.184.0.0/16140.184.0.1 to 140.184.255.254140.184.255.25565,534
186140.185.0.0/16140.185.0.1 to 140.185.255.254140.185.255.25565,534
187140.186.0.0/16140.186.0.1 to 140.186.255.254140.186.255.25565,534
188140.187.0.0/16140.187.0.1 to 140.187.255.254140.187.255.25565,534
189140.188.0.0/16140.188.0.1 to 140.188.255.254140.188.255.25565,534
190140.189.0.0/16140.189.0.1 to 140.189.255.254140.189.255.25565,534
191140.190.0.0/16140.190.0.1 to 140.190.255.254140.190.255.25565,534
192140.191.0.0/16140.191.0.1 to 140.191.255.254140.191.255.25565,534
193140.192.0.0/16140.192.0.1 to 140.192.255.254140.192.255.25565,534
194140.193.0.0/16140.193.0.1 to 140.193.255.254140.193.255.25565,534
195140.194.0.0/16140.194.0.1 to 140.194.255.254140.194.255.25565,534
196140.195.0.0/16140.195.0.1 to 140.195.255.254140.195.255.25565,534
197140.196.0.0/16140.196.0.1 to 140.196.255.254140.196.255.25565,534
198140.197.0.0/16140.197.0.1 to 140.197.255.254140.197.255.25565,534
199140.198.0.0/16140.198.0.1 to 140.198.255.254140.198.255.25565,534
200140.199.0.0/16140.199.0.1 to 140.199.255.254140.199.255.25565,534
201140.200.0.0/16140.200.0.1 to 140.200.255.254140.200.255.25565,534
202140.201.0.0/16140.201.0.1 to 140.201.255.254140.201.255.25565,534
203140.202.0.0/16140.202.0.1 to 140.202.255.254140.202.255.25565,534
204140.203.0.0/16140.203.0.1 to 140.203.255.254140.203.255.25565,534
205140.204.0.0/16140.204.0.1 to 140.204.255.254140.204.255.25565,534
206140.205.0.0/16140.205.0.1 to 140.205.255.254140.205.255.25565,534
207140.206.0.0/16140.206.0.1 to 140.206.255.254140.206.255.25565,534
208140.207.0.0/16140.207.0.1 to 140.207.255.254140.207.255.25565,534
209140.208.0.0/16140.208.0.1 to 140.208.255.254140.208.255.25565,534
210140.209.0.0/16140.209.0.1 to 140.209.255.254140.209.255.25565,534
211140.210.0.0/16140.210.0.1 to 140.210.255.254140.210.255.25565,534
212140.211.0.0/16140.211.0.1 to 140.211.255.254140.211.255.25565,534
213140.212.0.0/16140.212.0.1 to 140.212.255.254140.212.255.25565,534
214140.213.0.0/16140.213.0.1 to 140.213.255.254140.213.255.25565,534
215140.214.0.0/16140.214.0.1 to 140.214.255.254140.214.255.25565,534
216140.215.0.0/16140.215.0.1 to 140.215.255.254140.215.255.25565,534
217140.216.0.0/16140.216.0.1 to 140.216.255.254140.216.255.25565,534
218140.217.0.0/16140.217.0.1 to 140.217.255.254140.217.255.25565,534
219140.218.0.0/16140.218.0.1 to 140.218.255.254140.218.255.25565,534
220140.219.0.0/16140.219.0.1 to 140.219.255.254140.219.255.25565,534
221140.220.0.0/16140.220.0.1 to 140.220.255.254140.220.255.25565,534
222140.221.0.0/16140.221.0.1 to 140.221.255.254140.221.255.25565,534
223140.222.0.0/16140.222.0.1 to 140.222.255.254140.222.255.25565,534
224140.223.0.0/16140.223.0.1 to 140.223.255.254140.223.255.25565,534
225140.224.0.0/16140.224.0.1 to 140.224.255.254140.224.255.25565,534
226140.225.0.0/16140.225.0.1 to 140.225.255.254140.225.255.25565,534
227140.226.0.0/16140.226.0.1 to 140.226.255.254140.226.255.25565,534
228140.227.0.0/16140.227.0.1 to 140.227.255.254140.227.255.25565,534
229140.228.0.0/16140.228.0.1 to 140.228.255.254140.228.255.25565,534
230140.229.0.0/16140.229.0.1 to 140.229.255.254140.229.255.25565,534
231140.230.0.0/16140.230.0.1 to 140.230.255.254140.230.255.25565,534
232140.231.0.0/16140.231.0.1 to 140.231.255.254140.231.255.25565,534
233140.232.0.0/16140.232.0.1 to 140.232.255.254140.232.255.25565,534
234140.233.0.0/16140.233.0.1 to 140.233.255.254140.233.255.25565,534
235140.234.0.0/16140.234.0.1 to 140.234.255.254140.234.255.25565,534
236140.235.0.0/16140.235.0.1 to 140.235.255.254140.235.255.25565,534
237140.236.0.0/16140.236.0.1 to 140.236.255.254140.236.255.25565,534
238140.237.0.0/16140.237.0.1 to 140.237.255.254140.237.255.25565,534
239140.238.0.0/16140.238.0.1 to 140.238.255.254140.238.255.25565,534
240140.239.0.0/16140.239.0.1 to 140.239.255.254140.239.255.25565,534
241140.240.0.0/16140.240.0.1 to 140.240.255.254140.240.255.25565,534
242140.241.0.0/16140.241.0.1 to 140.241.255.254140.241.255.25565,534
243140.242.0.0/16140.242.0.1 to 140.242.255.254140.242.255.25565,534
244140.243.0.0/16140.243.0.1 to 140.243.255.254140.243.255.25565,534
245140.244.0.0/16140.244.0.1 to 140.244.255.254140.244.255.25565,534
246140.245.0.0/16140.245.0.1 to 140.245.255.254140.245.255.25565,534
247140.246.0.0/16140.246.0.1 to 140.246.255.254140.246.255.25565,534
248140.247.0.0/16140.247.0.1 to 140.247.255.254140.247.255.25565,534
249140.248.0.0/16140.248.0.1 to 140.248.255.254140.248.255.25565,534
250140.249.0.0/16140.249.0.1 to 140.249.255.254140.249.255.25565,534
251140.250.0.0/16140.250.0.1 to 140.250.255.254140.250.255.25565,534
252140.251.0.0/16140.251.0.1 to 140.251.255.254140.251.255.25565,534
253140.252.0.0/16140.252.0.1 to 140.252.255.254140.252.255.25565,534
254140.253.0.0/16140.253.0.1 to 140.253.255.254140.253.255.25565,534
255140.254.0.0/16140.254.0.1 to 140.254.255.254140.254.255.25565,534
256140.255.0.0/16140.255.0.1 to 140.255.255.254140.255.255.25565,534

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.