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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.

Network112.158.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
112.158.0.0
Broadcast address
112.158.255.255
First usable
112.158.0.1
Last usable
112.158.255.254
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 709E0000 · Integer 1889402880 to 1889468415
Reverse DNS zone
158.112.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110000.10011110..00000000.00000000112.158.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01110000.10011110..00000000.00000000112.158.0.0
Broadcast01110000.10011110..11111111.11111111112.158.255.255
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)

112.158.0.0/16 makes 256 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1112.158.0.0/24112.158.0.1 to 112.158.0.254112.158.0.255254
2112.158.1.0/24112.158.1.1 to 112.158.1.254112.158.1.255254
3112.158.2.0/24112.158.2.1 to 112.158.2.254112.158.2.255254
4112.158.3.0/24112.158.3.1 to 112.158.3.254112.158.3.255254
5112.158.4.0/24112.158.4.1 to 112.158.4.254112.158.4.255254
6112.158.5.0/24112.158.5.1 to 112.158.5.254112.158.5.255254
7112.158.6.0/24112.158.6.1 to 112.158.6.254112.158.6.255254
8112.158.7.0/24112.158.7.1 to 112.158.7.254112.158.7.255254
9112.158.8.0/24112.158.8.1 to 112.158.8.254112.158.8.255254
10112.158.9.0/24112.158.9.1 to 112.158.9.254112.158.9.255254
11112.158.10.0/24112.158.10.1 to 112.158.10.254112.158.10.255254
12112.158.11.0/24112.158.11.1 to 112.158.11.254112.158.11.255254
13112.158.12.0/24112.158.12.1 to 112.158.12.254112.158.12.255254
14112.158.13.0/24112.158.13.1 to 112.158.13.254112.158.13.255254
15112.158.14.0/24112.158.14.1 to 112.158.14.254112.158.14.255254
16112.158.15.0/24112.158.15.1 to 112.158.15.254112.158.15.255254
17112.158.16.0/24112.158.16.1 to 112.158.16.254112.158.16.255254
18112.158.17.0/24112.158.17.1 to 112.158.17.254112.158.17.255254
19112.158.18.0/24112.158.18.1 to 112.158.18.254112.158.18.255254
20112.158.19.0/24112.158.19.1 to 112.158.19.254112.158.19.255254
21112.158.20.0/24112.158.20.1 to 112.158.20.254112.158.20.255254
22112.158.21.0/24112.158.21.1 to 112.158.21.254112.158.21.255254
23112.158.22.0/24112.158.22.1 to 112.158.22.254112.158.22.255254
24112.158.23.0/24112.158.23.1 to 112.158.23.254112.158.23.255254
25112.158.24.0/24112.158.24.1 to 112.158.24.254112.158.24.255254
26112.158.25.0/24112.158.25.1 to 112.158.25.254112.158.25.255254
27112.158.26.0/24112.158.26.1 to 112.158.26.254112.158.26.255254
28112.158.27.0/24112.158.27.1 to 112.158.27.254112.158.27.255254
29112.158.28.0/24112.158.28.1 to 112.158.28.254112.158.28.255254
30112.158.29.0/24112.158.29.1 to 112.158.29.254112.158.29.255254
31112.158.30.0/24112.158.30.1 to 112.158.30.254112.158.30.255254
32112.158.31.0/24112.158.31.1 to 112.158.31.254112.158.31.255254
33112.158.32.0/24112.158.32.1 to 112.158.32.254112.158.32.255254
34112.158.33.0/24112.158.33.1 to 112.158.33.254112.158.33.255254
35112.158.34.0/24112.158.34.1 to 112.158.34.254112.158.34.255254
36112.158.35.0/24112.158.35.1 to 112.158.35.254112.158.35.255254
37112.158.36.0/24112.158.36.1 to 112.158.36.254112.158.36.255254
38112.158.37.0/24112.158.37.1 to 112.158.37.254112.158.37.255254
39112.158.38.0/24112.158.38.1 to 112.158.38.254112.158.38.255254
40112.158.39.0/24112.158.39.1 to 112.158.39.254112.158.39.255254
41112.158.40.0/24112.158.40.1 to 112.158.40.254112.158.40.255254
42112.158.41.0/24112.158.41.1 to 112.158.41.254112.158.41.255254
43112.158.42.0/24112.158.42.1 to 112.158.42.254112.158.42.255254
44112.158.43.0/24112.158.43.1 to 112.158.43.254112.158.43.255254
45112.158.44.0/24112.158.44.1 to 112.158.44.254112.158.44.255254
46112.158.45.0/24112.158.45.1 to 112.158.45.254112.158.45.255254
47112.158.46.0/24112.158.46.1 to 112.158.46.254112.158.46.255254
48112.158.47.0/24112.158.47.1 to 112.158.47.254112.158.47.255254
49112.158.48.0/24112.158.48.1 to 112.158.48.254112.158.48.255254
50112.158.49.0/24112.158.49.1 to 112.158.49.254112.158.49.255254
51112.158.50.0/24112.158.50.1 to 112.158.50.254112.158.50.255254
52112.158.51.0/24112.158.51.1 to 112.158.51.254112.158.51.255254
53112.158.52.0/24112.158.52.1 to 112.158.52.254112.158.52.255254
54112.158.53.0/24112.158.53.1 to 112.158.53.254112.158.53.255254
55112.158.54.0/24112.158.54.1 to 112.158.54.254112.158.54.255254
56112.158.55.0/24112.158.55.1 to 112.158.55.254112.158.55.255254
57112.158.56.0/24112.158.56.1 to 112.158.56.254112.158.56.255254
58112.158.57.0/24112.158.57.1 to 112.158.57.254112.158.57.255254
59112.158.58.0/24112.158.58.1 to 112.158.58.254112.158.58.255254
60112.158.59.0/24112.158.59.1 to 112.158.59.254112.158.59.255254
61112.158.60.0/24112.158.60.1 to 112.158.60.254112.158.60.255254
62112.158.61.0/24112.158.61.1 to 112.158.61.254112.158.61.255254
63112.158.62.0/24112.158.62.1 to 112.158.62.254112.158.62.255254
64112.158.63.0/24112.158.63.1 to 112.158.63.254112.158.63.255254
65112.158.64.0/24112.158.64.1 to 112.158.64.254112.158.64.255254
66112.158.65.0/24112.158.65.1 to 112.158.65.254112.158.65.255254
67112.158.66.0/24112.158.66.1 to 112.158.66.254112.158.66.255254
68112.158.67.0/24112.158.67.1 to 112.158.67.254112.158.67.255254
69112.158.68.0/24112.158.68.1 to 112.158.68.254112.158.68.255254
70112.158.69.0/24112.158.69.1 to 112.158.69.254112.158.69.255254
71112.158.70.0/24112.158.70.1 to 112.158.70.254112.158.70.255254
72112.158.71.0/24112.158.71.1 to 112.158.71.254112.158.71.255254
73112.158.72.0/24112.158.72.1 to 112.158.72.254112.158.72.255254
74112.158.73.0/24112.158.73.1 to 112.158.73.254112.158.73.255254
75112.158.74.0/24112.158.74.1 to 112.158.74.254112.158.74.255254
76112.158.75.0/24112.158.75.1 to 112.158.75.254112.158.75.255254
77112.158.76.0/24112.158.76.1 to 112.158.76.254112.158.76.255254
78112.158.77.0/24112.158.77.1 to 112.158.77.254112.158.77.255254
79112.158.78.0/24112.158.78.1 to 112.158.78.254112.158.78.255254
80112.158.79.0/24112.158.79.1 to 112.158.79.254112.158.79.255254
81112.158.80.0/24112.158.80.1 to 112.158.80.254112.158.80.255254
82112.158.81.0/24112.158.81.1 to 112.158.81.254112.158.81.255254
83112.158.82.0/24112.158.82.1 to 112.158.82.254112.158.82.255254
84112.158.83.0/24112.158.83.1 to 112.158.83.254112.158.83.255254
85112.158.84.0/24112.158.84.1 to 112.158.84.254112.158.84.255254
86112.158.85.0/24112.158.85.1 to 112.158.85.254112.158.85.255254
87112.158.86.0/24112.158.86.1 to 112.158.86.254112.158.86.255254
88112.158.87.0/24112.158.87.1 to 112.158.87.254112.158.87.255254
89112.158.88.0/24112.158.88.1 to 112.158.88.254112.158.88.255254
90112.158.89.0/24112.158.89.1 to 112.158.89.254112.158.89.255254
91112.158.90.0/24112.158.90.1 to 112.158.90.254112.158.90.255254
92112.158.91.0/24112.158.91.1 to 112.158.91.254112.158.91.255254
93112.158.92.0/24112.158.92.1 to 112.158.92.254112.158.92.255254
94112.158.93.0/24112.158.93.1 to 112.158.93.254112.158.93.255254
95112.158.94.0/24112.158.94.1 to 112.158.94.254112.158.94.255254
96112.158.95.0/24112.158.95.1 to 112.158.95.254112.158.95.255254
97112.158.96.0/24112.158.96.1 to 112.158.96.254112.158.96.255254
98112.158.97.0/24112.158.97.1 to 112.158.97.254112.158.97.255254
99112.158.98.0/24112.158.98.1 to 112.158.98.254112.158.98.255254
100112.158.99.0/24112.158.99.1 to 112.158.99.254112.158.99.255254
101112.158.100.0/24112.158.100.1 to 112.158.100.254112.158.100.255254
102112.158.101.0/24112.158.101.1 to 112.158.101.254112.158.101.255254
103112.158.102.0/24112.158.102.1 to 112.158.102.254112.158.102.255254
104112.158.103.0/24112.158.103.1 to 112.158.103.254112.158.103.255254
105112.158.104.0/24112.158.104.1 to 112.158.104.254112.158.104.255254
106112.158.105.0/24112.158.105.1 to 112.158.105.254112.158.105.255254
107112.158.106.0/24112.158.106.1 to 112.158.106.254112.158.106.255254
108112.158.107.0/24112.158.107.1 to 112.158.107.254112.158.107.255254
109112.158.108.0/24112.158.108.1 to 112.158.108.254112.158.108.255254
110112.158.109.0/24112.158.109.1 to 112.158.109.254112.158.109.255254
111112.158.110.0/24112.158.110.1 to 112.158.110.254112.158.110.255254
112112.158.111.0/24112.158.111.1 to 112.158.111.254112.158.111.255254
113112.158.112.0/24112.158.112.1 to 112.158.112.254112.158.112.255254
114112.158.113.0/24112.158.113.1 to 112.158.113.254112.158.113.255254
115112.158.114.0/24112.158.114.1 to 112.158.114.254112.158.114.255254
116112.158.115.0/24112.158.115.1 to 112.158.115.254112.158.115.255254
117112.158.116.0/24112.158.116.1 to 112.158.116.254112.158.116.255254
118112.158.117.0/24112.158.117.1 to 112.158.117.254112.158.117.255254
119112.158.118.0/24112.158.118.1 to 112.158.118.254112.158.118.255254
120112.158.119.0/24112.158.119.1 to 112.158.119.254112.158.119.255254
121112.158.120.0/24112.158.120.1 to 112.158.120.254112.158.120.255254
122112.158.121.0/24112.158.121.1 to 112.158.121.254112.158.121.255254
123112.158.122.0/24112.158.122.1 to 112.158.122.254112.158.122.255254
124112.158.123.0/24112.158.123.1 to 112.158.123.254112.158.123.255254
125112.158.124.0/24112.158.124.1 to 112.158.124.254112.158.124.255254
126112.158.125.0/24112.158.125.1 to 112.158.125.254112.158.125.255254
127112.158.126.0/24112.158.126.1 to 112.158.126.254112.158.126.255254
128112.158.127.0/24112.158.127.1 to 112.158.127.254112.158.127.255254
129112.158.128.0/24112.158.128.1 to 112.158.128.254112.158.128.255254
130112.158.129.0/24112.158.129.1 to 112.158.129.254112.158.129.255254
131112.158.130.0/24112.158.130.1 to 112.158.130.254112.158.130.255254
132112.158.131.0/24112.158.131.1 to 112.158.131.254112.158.131.255254
133112.158.132.0/24112.158.132.1 to 112.158.132.254112.158.132.255254
134112.158.133.0/24112.158.133.1 to 112.158.133.254112.158.133.255254
135112.158.134.0/24112.158.134.1 to 112.158.134.254112.158.134.255254
136112.158.135.0/24112.158.135.1 to 112.158.135.254112.158.135.255254
137112.158.136.0/24112.158.136.1 to 112.158.136.254112.158.136.255254
138112.158.137.0/24112.158.137.1 to 112.158.137.254112.158.137.255254
139112.158.138.0/24112.158.138.1 to 112.158.138.254112.158.138.255254
140112.158.139.0/24112.158.139.1 to 112.158.139.254112.158.139.255254
141112.158.140.0/24112.158.140.1 to 112.158.140.254112.158.140.255254
142112.158.141.0/24112.158.141.1 to 112.158.141.254112.158.141.255254
143112.158.142.0/24112.158.142.1 to 112.158.142.254112.158.142.255254
144112.158.143.0/24112.158.143.1 to 112.158.143.254112.158.143.255254
145112.158.144.0/24112.158.144.1 to 112.158.144.254112.158.144.255254
146112.158.145.0/24112.158.145.1 to 112.158.145.254112.158.145.255254
147112.158.146.0/24112.158.146.1 to 112.158.146.254112.158.146.255254
148112.158.147.0/24112.158.147.1 to 112.158.147.254112.158.147.255254
149112.158.148.0/24112.158.148.1 to 112.158.148.254112.158.148.255254
150112.158.149.0/24112.158.149.1 to 112.158.149.254112.158.149.255254
151112.158.150.0/24112.158.150.1 to 112.158.150.254112.158.150.255254
152112.158.151.0/24112.158.151.1 to 112.158.151.254112.158.151.255254
153112.158.152.0/24112.158.152.1 to 112.158.152.254112.158.152.255254
154112.158.153.0/24112.158.153.1 to 112.158.153.254112.158.153.255254
155112.158.154.0/24112.158.154.1 to 112.158.154.254112.158.154.255254
156112.158.155.0/24112.158.155.1 to 112.158.155.254112.158.155.255254
157112.158.156.0/24112.158.156.1 to 112.158.156.254112.158.156.255254
158112.158.157.0/24112.158.157.1 to 112.158.157.254112.158.157.255254
159112.158.158.0/24112.158.158.1 to 112.158.158.254112.158.158.255254
160112.158.159.0/24112.158.159.1 to 112.158.159.254112.158.159.255254
161112.158.160.0/24112.158.160.1 to 112.158.160.254112.158.160.255254
162112.158.161.0/24112.158.161.1 to 112.158.161.254112.158.161.255254
163112.158.162.0/24112.158.162.1 to 112.158.162.254112.158.162.255254
164112.158.163.0/24112.158.163.1 to 112.158.163.254112.158.163.255254
165112.158.164.0/24112.158.164.1 to 112.158.164.254112.158.164.255254
166112.158.165.0/24112.158.165.1 to 112.158.165.254112.158.165.255254
167112.158.166.0/24112.158.166.1 to 112.158.166.254112.158.166.255254
168112.158.167.0/24112.158.167.1 to 112.158.167.254112.158.167.255254
169112.158.168.0/24112.158.168.1 to 112.158.168.254112.158.168.255254
170112.158.169.0/24112.158.169.1 to 112.158.169.254112.158.169.255254
171112.158.170.0/24112.158.170.1 to 112.158.170.254112.158.170.255254
172112.158.171.0/24112.158.171.1 to 112.158.171.254112.158.171.255254
173112.158.172.0/24112.158.172.1 to 112.158.172.254112.158.172.255254
174112.158.173.0/24112.158.173.1 to 112.158.173.254112.158.173.255254
175112.158.174.0/24112.158.174.1 to 112.158.174.254112.158.174.255254
176112.158.175.0/24112.158.175.1 to 112.158.175.254112.158.175.255254
177112.158.176.0/24112.158.176.1 to 112.158.176.254112.158.176.255254
178112.158.177.0/24112.158.177.1 to 112.158.177.254112.158.177.255254
179112.158.178.0/24112.158.178.1 to 112.158.178.254112.158.178.255254
180112.158.179.0/24112.158.179.1 to 112.158.179.254112.158.179.255254
181112.158.180.0/24112.158.180.1 to 112.158.180.254112.158.180.255254
182112.158.181.0/24112.158.181.1 to 112.158.181.254112.158.181.255254
183112.158.182.0/24112.158.182.1 to 112.158.182.254112.158.182.255254
184112.158.183.0/24112.158.183.1 to 112.158.183.254112.158.183.255254
185112.158.184.0/24112.158.184.1 to 112.158.184.254112.158.184.255254
186112.158.185.0/24112.158.185.1 to 112.158.185.254112.158.185.255254
187112.158.186.0/24112.158.186.1 to 112.158.186.254112.158.186.255254
188112.158.187.0/24112.158.187.1 to 112.158.187.254112.158.187.255254
189112.158.188.0/24112.158.188.1 to 112.158.188.254112.158.188.255254
190112.158.189.0/24112.158.189.1 to 112.158.189.254112.158.189.255254
191112.158.190.0/24112.158.190.1 to 112.158.190.254112.158.190.255254
192112.158.191.0/24112.158.191.1 to 112.158.191.254112.158.191.255254
193112.158.192.0/24112.158.192.1 to 112.158.192.254112.158.192.255254
194112.158.193.0/24112.158.193.1 to 112.158.193.254112.158.193.255254
195112.158.194.0/24112.158.194.1 to 112.158.194.254112.158.194.255254
196112.158.195.0/24112.158.195.1 to 112.158.195.254112.158.195.255254
197112.158.196.0/24112.158.196.1 to 112.158.196.254112.158.196.255254
198112.158.197.0/24112.158.197.1 to 112.158.197.254112.158.197.255254
199112.158.198.0/24112.158.198.1 to 112.158.198.254112.158.198.255254
200112.158.199.0/24112.158.199.1 to 112.158.199.254112.158.199.255254
201112.158.200.0/24112.158.200.1 to 112.158.200.254112.158.200.255254
202112.158.201.0/24112.158.201.1 to 112.158.201.254112.158.201.255254
203112.158.202.0/24112.158.202.1 to 112.158.202.254112.158.202.255254
204112.158.203.0/24112.158.203.1 to 112.158.203.254112.158.203.255254
205112.158.204.0/24112.158.204.1 to 112.158.204.254112.158.204.255254
206112.158.205.0/24112.158.205.1 to 112.158.205.254112.158.205.255254
207112.158.206.0/24112.158.206.1 to 112.158.206.254112.158.206.255254
208112.158.207.0/24112.158.207.1 to 112.158.207.254112.158.207.255254
209112.158.208.0/24112.158.208.1 to 112.158.208.254112.158.208.255254
210112.158.209.0/24112.158.209.1 to 112.158.209.254112.158.209.255254
211112.158.210.0/24112.158.210.1 to 112.158.210.254112.158.210.255254
212112.158.211.0/24112.158.211.1 to 112.158.211.254112.158.211.255254
213112.158.212.0/24112.158.212.1 to 112.158.212.254112.158.212.255254
214112.158.213.0/24112.158.213.1 to 112.158.213.254112.158.213.255254
215112.158.214.0/24112.158.214.1 to 112.158.214.254112.158.214.255254
216112.158.215.0/24112.158.215.1 to 112.158.215.254112.158.215.255254
217112.158.216.0/24112.158.216.1 to 112.158.216.254112.158.216.255254
218112.158.217.0/24112.158.217.1 to 112.158.217.254112.158.217.255254
219112.158.218.0/24112.158.218.1 to 112.158.218.254112.158.218.255254
220112.158.219.0/24112.158.219.1 to 112.158.219.254112.158.219.255254
221112.158.220.0/24112.158.220.1 to 112.158.220.254112.158.220.255254
222112.158.221.0/24112.158.221.1 to 112.158.221.254112.158.221.255254
223112.158.222.0/24112.158.222.1 to 112.158.222.254112.158.222.255254
224112.158.223.0/24112.158.223.1 to 112.158.223.254112.158.223.255254
225112.158.224.0/24112.158.224.1 to 112.158.224.254112.158.224.255254
226112.158.225.0/24112.158.225.1 to 112.158.225.254112.158.225.255254
227112.158.226.0/24112.158.226.1 to 112.158.226.254112.158.226.255254
228112.158.227.0/24112.158.227.1 to 112.158.227.254112.158.227.255254
229112.158.228.0/24112.158.228.1 to 112.158.228.254112.158.228.255254
230112.158.229.0/24112.158.229.1 to 112.158.229.254112.158.229.255254
231112.158.230.0/24112.158.230.1 to 112.158.230.254112.158.230.255254
232112.158.231.0/24112.158.231.1 to 112.158.231.254112.158.231.255254
233112.158.232.0/24112.158.232.1 to 112.158.232.254112.158.232.255254
234112.158.233.0/24112.158.233.1 to 112.158.233.254112.158.233.255254
235112.158.234.0/24112.158.234.1 to 112.158.234.254112.158.234.255254
236112.158.235.0/24112.158.235.1 to 112.158.235.254112.158.235.255254
237112.158.236.0/24112.158.236.1 to 112.158.236.254112.158.236.255254
238112.158.237.0/24112.158.237.1 to 112.158.237.254112.158.237.255254
239112.158.238.0/24112.158.238.1 to 112.158.238.254112.158.238.255254
240112.158.239.0/24112.158.239.1 to 112.158.239.254112.158.239.255254
241112.158.240.0/24112.158.240.1 to 112.158.240.254112.158.240.255254
242112.158.241.0/24112.158.241.1 to 112.158.241.254112.158.241.255254
243112.158.242.0/24112.158.242.1 to 112.158.242.254112.158.242.255254
244112.158.243.0/24112.158.243.1 to 112.158.243.254112.158.243.255254
245112.158.244.0/24112.158.244.1 to 112.158.244.254112.158.244.255254
246112.158.245.0/24112.158.245.1 to 112.158.245.254112.158.245.255254
247112.158.246.0/24112.158.246.1 to 112.158.246.254112.158.246.255254
248112.158.247.0/24112.158.247.1 to 112.158.247.254112.158.247.255254
249112.158.248.0/24112.158.248.1 to 112.158.248.254112.158.248.255254
250112.158.249.0/24112.158.249.1 to 112.158.249.254112.158.249.255254
251112.158.250.0/24112.158.250.1 to 112.158.250.254112.158.250.255254
252112.158.251.0/24112.158.251.1 to 112.158.251.254112.158.251.255254
253112.158.252.0/24112.158.252.1 to 112.158.252.254112.158.252.255254
254112.158.253.0/24112.158.253.1 to 112.158.253.254112.158.253.255254
255112.158.254.0/24112.158.254.1 to 112.158.254.254112.158.254.255254
256112.158.255.0/24112.158.255.1 to 112.158.255.254112.158.255.255254

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.