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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.

Network153.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
153.0.0.0
Broadcast address
153.255.255.255
First usable
153.0.0.1
Last usable
153.255.255.254
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 99000000 · Integer 2566914048 to 2583691263
Reverse DNS zone
153.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10011001..00000000.00000000.00000000153.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10011001..00000000.00000000.00000000153.0.0.0
Broadcast10011001..11111111.11111111.11111111153.255.255.255
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)

153.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1153.0.0.0/16153.0.0.1 to 153.0.255.254153.0.255.25565,534
2153.1.0.0/16153.1.0.1 to 153.1.255.254153.1.255.25565,534
3153.2.0.0/16153.2.0.1 to 153.2.255.254153.2.255.25565,534
4153.3.0.0/16153.3.0.1 to 153.3.255.254153.3.255.25565,534
5153.4.0.0/16153.4.0.1 to 153.4.255.254153.4.255.25565,534
6153.5.0.0/16153.5.0.1 to 153.5.255.254153.5.255.25565,534
7153.6.0.0/16153.6.0.1 to 153.6.255.254153.6.255.25565,534
8153.7.0.0/16153.7.0.1 to 153.7.255.254153.7.255.25565,534
9153.8.0.0/16153.8.0.1 to 153.8.255.254153.8.255.25565,534
10153.9.0.0/16153.9.0.1 to 153.9.255.254153.9.255.25565,534
11153.10.0.0/16153.10.0.1 to 153.10.255.254153.10.255.25565,534
12153.11.0.0/16153.11.0.1 to 153.11.255.254153.11.255.25565,534
13153.12.0.0/16153.12.0.1 to 153.12.255.254153.12.255.25565,534
14153.13.0.0/16153.13.0.1 to 153.13.255.254153.13.255.25565,534
15153.14.0.0/16153.14.0.1 to 153.14.255.254153.14.255.25565,534
16153.15.0.0/16153.15.0.1 to 153.15.255.254153.15.255.25565,534
17153.16.0.0/16153.16.0.1 to 153.16.255.254153.16.255.25565,534
18153.17.0.0/16153.17.0.1 to 153.17.255.254153.17.255.25565,534
19153.18.0.0/16153.18.0.1 to 153.18.255.254153.18.255.25565,534
20153.19.0.0/16153.19.0.1 to 153.19.255.254153.19.255.25565,534
21153.20.0.0/16153.20.0.1 to 153.20.255.254153.20.255.25565,534
22153.21.0.0/16153.21.0.1 to 153.21.255.254153.21.255.25565,534
23153.22.0.0/16153.22.0.1 to 153.22.255.254153.22.255.25565,534
24153.23.0.0/16153.23.0.1 to 153.23.255.254153.23.255.25565,534
25153.24.0.0/16153.24.0.1 to 153.24.255.254153.24.255.25565,534
26153.25.0.0/16153.25.0.1 to 153.25.255.254153.25.255.25565,534
27153.26.0.0/16153.26.0.1 to 153.26.255.254153.26.255.25565,534
28153.27.0.0/16153.27.0.1 to 153.27.255.254153.27.255.25565,534
29153.28.0.0/16153.28.0.1 to 153.28.255.254153.28.255.25565,534
30153.29.0.0/16153.29.0.1 to 153.29.255.254153.29.255.25565,534
31153.30.0.0/16153.30.0.1 to 153.30.255.254153.30.255.25565,534
32153.31.0.0/16153.31.0.1 to 153.31.255.254153.31.255.25565,534
33153.32.0.0/16153.32.0.1 to 153.32.255.254153.32.255.25565,534
34153.33.0.0/16153.33.0.1 to 153.33.255.254153.33.255.25565,534
35153.34.0.0/16153.34.0.1 to 153.34.255.254153.34.255.25565,534
36153.35.0.0/16153.35.0.1 to 153.35.255.254153.35.255.25565,534
37153.36.0.0/16153.36.0.1 to 153.36.255.254153.36.255.25565,534
38153.37.0.0/16153.37.0.1 to 153.37.255.254153.37.255.25565,534
39153.38.0.0/16153.38.0.1 to 153.38.255.254153.38.255.25565,534
40153.39.0.0/16153.39.0.1 to 153.39.255.254153.39.255.25565,534
41153.40.0.0/16153.40.0.1 to 153.40.255.254153.40.255.25565,534
42153.41.0.0/16153.41.0.1 to 153.41.255.254153.41.255.25565,534
43153.42.0.0/16153.42.0.1 to 153.42.255.254153.42.255.25565,534
44153.43.0.0/16153.43.0.1 to 153.43.255.254153.43.255.25565,534
45153.44.0.0/16153.44.0.1 to 153.44.255.254153.44.255.25565,534
46153.45.0.0/16153.45.0.1 to 153.45.255.254153.45.255.25565,534
47153.46.0.0/16153.46.0.1 to 153.46.255.254153.46.255.25565,534
48153.47.0.0/16153.47.0.1 to 153.47.255.254153.47.255.25565,534
49153.48.0.0/16153.48.0.1 to 153.48.255.254153.48.255.25565,534
50153.49.0.0/16153.49.0.1 to 153.49.255.254153.49.255.25565,534
51153.50.0.0/16153.50.0.1 to 153.50.255.254153.50.255.25565,534
52153.51.0.0/16153.51.0.1 to 153.51.255.254153.51.255.25565,534
53153.52.0.0/16153.52.0.1 to 153.52.255.254153.52.255.25565,534
54153.53.0.0/16153.53.0.1 to 153.53.255.254153.53.255.25565,534
55153.54.0.0/16153.54.0.1 to 153.54.255.254153.54.255.25565,534
56153.55.0.0/16153.55.0.1 to 153.55.255.254153.55.255.25565,534
57153.56.0.0/16153.56.0.1 to 153.56.255.254153.56.255.25565,534
58153.57.0.0/16153.57.0.1 to 153.57.255.254153.57.255.25565,534
59153.58.0.0/16153.58.0.1 to 153.58.255.254153.58.255.25565,534
60153.59.0.0/16153.59.0.1 to 153.59.255.254153.59.255.25565,534
61153.60.0.0/16153.60.0.1 to 153.60.255.254153.60.255.25565,534
62153.61.0.0/16153.61.0.1 to 153.61.255.254153.61.255.25565,534
63153.62.0.0/16153.62.0.1 to 153.62.255.254153.62.255.25565,534
64153.63.0.0/16153.63.0.1 to 153.63.255.254153.63.255.25565,534
65153.64.0.0/16153.64.0.1 to 153.64.255.254153.64.255.25565,534
66153.65.0.0/16153.65.0.1 to 153.65.255.254153.65.255.25565,534
67153.66.0.0/16153.66.0.1 to 153.66.255.254153.66.255.25565,534
68153.67.0.0/16153.67.0.1 to 153.67.255.254153.67.255.25565,534
69153.68.0.0/16153.68.0.1 to 153.68.255.254153.68.255.25565,534
70153.69.0.0/16153.69.0.1 to 153.69.255.254153.69.255.25565,534
71153.70.0.0/16153.70.0.1 to 153.70.255.254153.70.255.25565,534
72153.71.0.0/16153.71.0.1 to 153.71.255.254153.71.255.25565,534
73153.72.0.0/16153.72.0.1 to 153.72.255.254153.72.255.25565,534
74153.73.0.0/16153.73.0.1 to 153.73.255.254153.73.255.25565,534
75153.74.0.0/16153.74.0.1 to 153.74.255.254153.74.255.25565,534
76153.75.0.0/16153.75.0.1 to 153.75.255.254153.75.255.25565,534
77153.76.0.0/16153.76.0.1 to 153.76.255.254153.76.255.25565,534
78153.77.0.0/16153.77.0.1 to 153.77.255.254153.77.255.25565,534
79153.78.0.0/16153.78.0.1 to 153.78.255.254153.78.255.25565,534
80153.79.0.0/16153.79.0.1 to 153.79.255.254153.79.255.25565,534
81153.80.0.0/16153.80.0.1 to 153.80.255.254153.80.255.25565,534
82153.81.0.0/16153.81.0.1 to 153.81.255.254153.81.255.25565,534
83153.82.0.0/16153.82.0.1 to 153.82.255.254153.82.255.25565,534
84153.83.0.0/16153.83.0.1 to 153.83.255.254153.83.255.25565,534
85153.84.0.0/16153.84.0.1 to 153.84.255.254153.84.255.25565,534
86153.85.0.0/16153.85.0.1 to 153.85.255.254153.85.255.25565,534
87153.86.0.0/16153.86.0.1 to 153.86.255.254153.86.255.25565,534
88153.87.0.0/16153.87.0.1 to 153.87.255.254153.87.255.25565,534
89153.88.0.0/16153.88.0.1 to 153.88.255.254153.88.255.25565,534
90153.89.0.0/16153.89.0.1 to 153.89.255.254153.89.255.25565,534
91153.90.0.0/16153.90.0.1 to 153.90.255.254153.90.255.25565,534
92153.91.0.0/16153.91.0.1 to 153.91.255.254153.91.255.25565,534
93153.92.0.0/16153.92.0.1 to 153.92.255.254153.92.255.25565,534
94153.93.0.0/16153.93.0.1 to 153.93.255.254153.93.255.25565,534
95153.94.0.0/16153.94.0.1 to 153.94.255.254153.94.255.25565,534
96153.95.0.0/16153.95.0.1 to 153.95.255.254153.95.255.25565,534
97153.96.0.0/16153.96.0.1 to 153.96.255.254153.96.255.25565,534
98153.97.0.0/16153.97.0.1 to 153.97.255.254153.97.255.25565,534
99153.98.0.0/16153.98.0.1 to 153.98.255.254153.98.255.25565,534
100153.99.0.0/16153.99.0.1 to 153.99.255.254153.99.255.25565,534
101153.100.0.0/16153.100.0.1 to 153.100.255.254153.100.255.25565,534
102153.101.0.0/16153.101.0.1 to 153.101.255.254153.101.255.25565,534
103153.102.0.0/16153.102.0.1 to 153.102.255.254153.102.255.25565,534
104153.103.0.0/16153.103.0.1 to 153.103.255.254153.103.255.25565,534
105153.104.0.0/16153.104.0.1 to 153.104.255.254153.104.255.25565,534
106153.105.0.0/16153.105.0.1 to 153.105.255.254153.105.255.25565,534
107153.106.0.0/16153.106.0.1 to 153.106.255.254153.106.255.25565,534
108153.107.0.0/16153.107.0.1 to 153.107.255.254153.107.255.25565,534
109153.108.0.0/16153.108.0.1 to 153.108.255.254153.108.255.25565,534
110153.109.0.0/16153.109.0.1 to 153.109.255.254153.109.255.25565,534
111153.110.0.0/16153.110.0.1 to 153.110.255.254153.110.255.25565,534
112153.111.0.0/16153.111.0.1 to 153.111.255.254153.111.255.25565,534
113153.112.0.0/16153.112.0.1 to 153.112.255.254153.112.255.25565,534
114153.113.0.0/16153.113.0.1 to 153.113.255.254153.113.255.25565,534
115153.114.0.0/16153.114.0.1 to 153.114.255.254153.114.255.25565,534
116153.115.0.0/16153.115.0.1 to 153.115.255.254153.115.255.25565,534
117153.116.0.0/16153.116.0.1 to 153.116.255.254153.116.255.25565,534
118153.117.0.0/16153.117.0.1 to 153.117.255.254153.117.255.25565,534
119153.118.0.0/16153.118.0.1 to 153.118.255.254153.118.255.25565,534
120153.119.0.0/16153.119.0.1 to 153.119.255.254153.119.255.25565,534
121153.120.0.0/16153.120.0.1 to 153.120.255.254153.120.255.25565,534
122153.121.0.0/16153.121.0.1 to 153.121.255.254153.121.255.25565,534
123153.122.0.0/16153.122.0.1 to 153.122.255.254153.122.255.25565,534
124153.123.0.0/16153.123.0.1 to 153.123.255.254153.123.255.25565,534
125153.124.0.0/16153.124.0.1 to 153.124.255.254153.124.255.25565,534
126153.125.0.0/16153.125.0.1 to 153.125.255.254153.125.255.25565,534
127153.126.0.0/16153.126.0.1 to 153.126.255.254153.126.255.25565,534
128153.127.0.0/16153.127.0.1 to 153.127.255.254153.127.255.25565,534
129153.128.0.0/16153.128.0.1 to 153.128.255.254153.128.255.25565,534
130153.129.0.0/16153.129.0.1 to 153.129.255.254153.129.255.25565,534
131153.130.0.0/16153.130.0.1 to 153.130.255.254153.130.255.25565,534
132153.131.0.0/16153.131.0.1 to 153.131.255.254153.131.255.25565,534
133153.132.0.0/16153.132.0.1 to 153.132.255.254153.132.255.25565,534
134153.133.0.0/16153.133.0.1 to 153.133.255.254153.133.255.25565,534
135153.134.0.0/16153.134.0.1 to 153.134.255.254153.134.255.25565,534
136153.135.0.0/16153.135.0.1 to 153.135.255.254153.135.255.25565,534
137153.136.0.0/16153.136.0.1 to 153.136.255.254153.136.255.25565,534
138153.137.0.0/16153.137.0.1 to 153.137.255.254153.137.255.25565,534
139153.138.0.0/16153.138.0.1 to 153.138.255.254153.138.255.25565,534
140153.139.0.0/16153.139.0.1 to 153.139.255.254153.139.255.25565,534
141153.140.0.0/16153.140.0.1 to 153.140.255.254153.140.255.25565,534
142153.141.0.0/16153.141.0.1 to 153.141.255.254153.141.255.25565,534
143153.142.0.0/16153.142.0.1 to 153.142.255.254153.142.255.25565,534
144153.143.0.0/16153.143.0.1 to 153.143.255.254153.143.255.25565,534
145153.144.0.0/16153.144.0.1 to 153.144.255.254153.144.255.25565,534
146153.145.0.0/16153.145.0.1 to 153.145.255.254153.145.255.25565,534
147153.146.0.0/16153.146.0.1 to 153.146.255.254153.146.255.25565,534
148153.147.0.0/16153.147.0.1 to 153.147.255.254153.147.255.25565,534
149153.148.0.0/16153.148.0.1 to 153.148.255.254153.148.255.25565,534
150153.149.0.0/16153.149.0.1 to 153.149.255.254153.149.255.25565,534
151153.150.0.0/16153.150.0.1 to 153.150.255.254153.150.255.25565,534
152153.151.0.0/16153.151.0.1 to 153.151.255.254153.151.255.25565,534
153153.152.0.0/16153.152.0.1 to 153.152.255.254153.152.255.25565,534
154153.153.0.0/16153.153.0.1 to 153.153.255.254153.153.255.25565,534
155153.154.0.0/16153.154.0.1 to 153.154.255.254153.154.255.25565,534
156153.155.0.0/16153.155.0.1 to 153.155.255.254153.155.255.25565,534
157153.156.0.0/16153.156.0.1 to 153.156.255.254153.156.255.25565,534
158153.157.0.0/16153.157.0.1 to 153.157.255.254153.157.255.25565,534
159153.158.0.0/16153.158.0.1 to 153.158.255.254153.158.255.25565,534
160153.159.0.0/16153.159.0.1 to 153.159.255.254153.159.255.25565,534
161153.160.0.0/16153.160.0.1 to 153.160.255.254153.160.255.25565,534
162153.161.0.0/16153.161.0.1 to 153.161.255.254153.161.255.25565,534
163153.162.0.0/16153.162.0.1 to 153.162.255.254153.162.255.25565,534
164153.163.0.0/16153.163.0.1 to 153.163.255.254153.163.255.25565,534
165153.164.0.0/16153.164.0.1 to 153.164.255.254153.164.255.25565,534
166153.165.0.0/16153.165.0.1 to 153.165.255.254153.165.255.25565,534
167153.166.0.0/16153.166.0.1 to 153.166.255.254153.166.255.25565,534
168153.167.0.0/16153.167.0.1 to 153.167.255.254153.167.255.25565,534
169153.168.0.0/16153.168.0.1 to 153.168.255.254153.168.255.25565,534
170153.169.0.0/16153.169.0.1 to 153.169.255.254153.169.255.25565,534
171153.170.0.0/16153.170.0.1 to 153.170.255.254153.170.255.25565,534
172153.171.0.0/16153.171.0.1 to 153.171.255.254153.171.255.25565,534
173153.172.0.0/16153.172.0.1 to 153.172.255.254153.172.255.25565,534
174153.173.0.0/16153.173.0.1 to 153.173.255.254153.173.255.25565,534
175153.174.0.0/16153.174.0.1 to 153.174.255.254153.174.255.25565,534
176153.175.0.0/16153.175.0.1 to 153.175.255.254153.175.255.25565,534
177153.176.0.0/16153.176.0.1 to 153.176.255.254153.176.255.25565,534
178153.177.0.0/16153.177.0.1 to 153.177.255.254153.177.255.25565,534
179153.178.0.0/16153.178.0.1 to 153.178.255.254153.178.255.25565,534
180153.179.0.0/16153.179.0.1 to 153.179.255.254153.179.255.25565,534
181153.180.0.0/16153.180.0.1 to 153.180.255.254153.180.255.25565,534
182153.181.0.0/16153.181.0.1 to 153.181.255.254153.181.255.25565,534
183153.182.0.0/16153.182.0.1 to 153.182.255.254153.182.255.25565,534
184153.183.0.0/16153.183.0.1 to 153.183.255.254153.183.255.25565,534
185153.184.0.0/16153.184.0.1 to 153.184.255.254153.184.255.25565,534
186153.185.0.0/16153.185.0.1 to 153.185.255.254153.185.255.25565,534
187153.186.0.0/16153.186.0.1 to 153.186.255.254153.186.255.25565,534
188153.187.0.0/16153.187.0.1 to 153.187.255.254153.187.255.25565,534
189153.188.0.0/16153.188.0.1 to 153.188.255.254153.188.255.25565,534
190153.189.0.0/16153.189.0.1 to 153.189.255.254153.189.255.25565,534
191153.190.0.0/16153.190.0.1 to 153.190.255.254153.190.255.25565,534
192153.191.0.0/16153.191.0.1 to 153.191.255.254153.191.255.25565,534
193153.192.0.0/16153.192.0.1 to 153.192.255.254153.192.255.25565,534
194153.193.0.0/16153.193.0.1 to 153.193.255.254153.193.255.25565,534
195153.194.0.0/16153.194.0.1 to 153.194.255.254153.194.255.25565,534
196153.195.0.0/16153.195.0.1 to 153.195.255.254153.195.255.25565,534
197153.196.0.0/16153.196.0.1 to 153.196.255.254153.196.255.25565,534
198153.197.0.0/16153.197.0.1 to 153.197.255.254153.197.255.25565,534
199153.198.0.0/16153.198.0.1 to 153.198.255.254153.198.255.25565,534
200153.199.0.0/16153.199.0.1 to 153.199.255.254153.199.255.25565,534
201153.200.0.0/16153.200.0.1 to 153.200.255.254153.200.255.25565,534
202153.201.0.0/16153.201.0.1 to 153.201.255.254153.201.255.25565,534
203153.202.0.0/16153.202.0.1 to 153.202.255.254153.202.255.25565,534
204153.203.0.0/16153.203.0.1 to 153.203.255.254153.203.255.25565,534
205153.204.0.0/16153.204.0.1 to 153.204.255.254153.204.255.25565,534
206153.205.0.0/16153.205.0.1 to 153.205.255.254153.205.255.25565,534
207153.206.0.0/16153.206.0.1 to 153.206.255.254153.206.255.25565,534
208153.207.0.0/16153.207.0.1 to 153.207.255.254153.207.255.25565,534
209153.208.0.0/16153.208.0.1 to 153.208.255.254153.208.255.25565,534
210153.209.0.0/16153.209.0.1 to 153.209.255.254153.209.255.25565,534
211153.210.0.0/16153.210.0.1 to 153.210.255.254153.210.255.25565,534
212153.211.0.0/16153.211.0.1 to 153.211.255.254153.211.255.25565,534
213153.212.0.0/16153.212.0.1 to 153.212.255.254153.212.255.25565,534
214153.213.0.0/16153.213.0.1 to 153.213.255.254153.213.255.25565,534
215153.214.0.0/16153.214.0.1 to 153.214.255.254153.214.255.25565,534
216153.215.0.0/16153.215.0.1 to 153.215.255.254153.215.255.25565,534
217153.216.0.0/16153.216.0.1 to 153.216.255.254153.216.255.25565,534
218153.217.0.0/16153.217.0.1 to 153.217.255.254153.217.255.25565,534
219153.218.0.0/16153.218.0.1 to 153.218.255.254153.218.255.25565,534
220153.219.0.0/16153.219.0.1 to 153.219.255.254153.219.255.25565,534
221153.220.0.0/16153.220.0.1 to 153.220.255.254153.220.255.25565,534
222153.221.0.0/16153.221.0.1 to 153.221.255.254153.221.255.25565,534
223153.222.0.0/16153.222.0.1 to 153.222.255.254153.222.255.25565,534
224153.223.0.0/16153.223.0.1 to 153.223.255.254153.223.255.25565,534
225153.224.0.0/16153.224.0.1 to 153.224.255.254153.224.255.25565,534
226153.225.0.0/16153.225.0.1 to 153.225.255.254153.225.255.25565,534
227153.226.0.0/16153.226.0.1 to 153.226.255.254153.226.255.25565,534
228153.227.0.0/16153.227.0.1 to 153.227.255.254153.227.255.25565,534
229153.228.0.0/16153.228.0.1 to 153.228.255.254153.228.255.25565,534
230153.229.0.0/16153.229.0.1 to 153.229.255.254153.229.255.25565,534
231153.230.0.0/16153.230.0.1 to 153.230.255.254153.230.255.25565,534
232153.231.0.0/16153.231.0.1 to 153.231.255.254153.231.255.25565,534
233153.232.0.0/16153.232.0.1 to 153.232.255.254153.232.255.25565,534
234153.233.0.0/16153.233.0.1 to 153.233.255.254153.233.255.25565,534
235153.234.0.0/16153.234.0.1 to 153.234.255.254153.234.255.25565,534
236153.235.0.0/16153.235.0.1 to 153.235.255.254153.235.255.25565,534
237153.236.0.0/16153.236.0.1 to 153.236.255.254153.236.255.25565,534
238153.237.0.0/16153.237.0.1 to 153.237.255.254153.237.255.25565,534
239153.238.0.0/16153.238.0.1 to 153.238.255.254153.238.255.25565,534
240153.239.0.0/16153.239.0.1 to 153.239.255.254153.239.255.25565,534
241153.240.0.0/16153.240.0.1 to 153.240.255.254153.240.255.25565,534
242153.241.0.0/16153.241.0.1 to 153.241.255.254153.241.255.25565,534
243153.242.0.0/16153.242.0.1 to 153.242.255.254153.242.255.25565,534
244153.243.0.0/16153.243.0.1 to 153.243.255.254153.243.255.25565,534
245153.244.0.0/16153.244.0.1 to 153.244.255.254153.244.255.25565,534
246153.245.0.0/16153.245.0.1 to 153.245.255.254153.245.255.25565,534
247153.246.0.0/16153.246.0.1 to 153.246.255.254153.246.255.25565,534
248153.247.0.0/16153.247.0.1 to 153.247.255.254153.247.255.25565,534
249153.248.0.0/16153.248.0.1 to 153.248.255.254153.248.255.25565,534
250153.249.0.0/16153.249.0.1 to 153.249.255.254153.249.255.25565,534
251153.250.0.0/16153.250.0.1 to 153.250.255.254153.250.255.25565,534
252153.251.0.0/16153.251.0.1 to 153.251.255.254153.251.255.25565,534
253153.252.0.0/16153.252.0.1 to 153.252.255.254153.252.255.25565,534
254153.253.0.0/16153.253.0.1 to 153.253.255.254153.253.255.25565,534
255153.254.0.0/16153.254.0.1 to 153.254.255.254153.254.255.25565,534
256153.255.0.0/16153.255.0.1 to 153.255.255.254153.255.255.25565,534

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.