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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.

Network130.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
130.232.0.0
Broadcast address
130.235.255.255
First usable
130.232.0.1
Last usable
130.235.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
B (default /16)
As numbers
Hex 82E80000 · Integer 2196242432 to 2196504575
Reverse DNS zones
232.130.in-addr.arpa
233.130.in-addr.arpa
234.130.in-addr.arpa
235.130.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10000010.11101000.00000000.00000000130.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10000010.11101000.00000000.00000000130.232.0.0
Broadcast10000010.11101011.11111111.11111111130.235.255.255
Split into smaller subnets/23
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

130.232.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1130.232.0.0/23130.232.0.1 to 130.232.1.254130.232.1.255510
2130.232.2.0/23130.232.2.1 to 130.232.3.254130.232.3.255510
3130.232.4.0/23130.232.4.1 to 130.232.5.254130.232.5.255510
4130.232.6.0/23130.232.6.1 to 130.232.7.254130.232.7.255510
5130.232.8.0/23130.232.8.1 to 130.232.9.254130.232.9.255510
6130.232.10.0/23130.232.10.1 to 130.232.11.254130.232.11.255510
7130.232.12.0/23130.232.12.1 to 130.232.13.254130.232.13.255510
8130.232.14.0/23130.232.14.1 to 130.232.15.254130.232.15.255510
9130.232.16.0/23130.232.16.1 to 130.232.17.254130.232.17.255510
10130.232.18.0/23130.232.18.1 to 130.232.19.254130.232.19.255510
11130.232.20.0/23130.232.20.1 to 130.232.21.254130.232.21.255510
12130.232.22.0/23130.232.22.1 to 130.232.23.254130.232.23.255510
13130.232.24.0/23130.232.24.1 to 130.232.25.254130.232.25.255510
14130.232.26.0/23130.232.26.1 to 130.232.27.254130.232.27.255510
15130.232.28.0/23130.232.28.1 to 130.232.29.254130.232.29.255510
16130.232.30.0/23130.232.30.1 to 130.232.31.254130.232.31.255510
17130.232.32.0/23130.232.32.1 to 130.232.33.254130.232.33.255510
18130.232.34.0/23130.232.34.1 to 130.232.35.254130.232.35.255510
19130.232.36.0/23130.232.36.1 to 130.232.37.254130.232.37.255510
20130.232.38.0/23130.232.38.1 to 130.232.39.254130.232.39.255510
21130.232.40.0/23130.232.40.1 to 130.232.41.254130.232.41.255510
22130.232.42.0/23130.232.42.1 to 130.232.43.254130.232.43.255510
23130.232.44.0/23130.232.44.1 to 130.232.45.254130.232.45.255510
24130.232.46.0/23130.232.46.1 to 130.232.47.254130.232.47.255510
25130.232.48.0/23130.232.48.1 to 130.232.49.254130.232.49.255510
26130.232.50.0/23130.232.50.1 to 130.232.51.254130.232.51.255510
27130.232.52.0/23130.232.52.1 to 130.232.53.254130.232.53.255510
28130.232.54.0/23130.232.54.1 to 130.232.55.254130.232.55.255510
29130.232.56.0/23130.232.56.1 to 130.232.57.254130.232.57.255510
30130.232.58.0/23130.232.58.1 to 130.232.59.254130.232.59.255510
31130.232.60.0/23130.232.60.1 to 130.232.61.254130.232.61.255510
32130.232.62.0/23130.232.62.1 to 130.232.63.254130.232.63.255510
33130.232.64.0/23130.232.64.1 to 130.232.65.254130.232.65.255510
34130.232.66.0/23130.232.66.1 to 130.232.67.254130.232.67.255510
35130.232.68.0/23130.232.68.1 to 130.232.69.254130.232.69.255510
36130.232.70.0/23130.232.70.1 to 130.232.71.254130.232.71.255510
37130.232.72.0/23130.232.72.1 to 130.232.73.254130.232.73.255510
38130.232.74.0/23130.232.74.1 to 130.232.75.254130.232.75.255510
39130.232.76.0/23130.232.76.1 to 130.232.77.254130.232.77.255510
40130.232.78.0/23130.232.78.1 to 130.232.79.254130.232.79.255510
41130.232.80.0/23130.232.80.1 to 130.232.81.254130.232.81.255510
42130.232.82.0/23130.232.82.1 to 130.232.83.254130.232.83.255510
43130.232.84.0/23130.232.84.1 to 130.232.85.254130.232.85.255510
44130.232.86.0/23130.232.86.1 to 130.232.87.254130.232.87.255510
45130.232.88.0/23130.232.88.1 to 130.232.89.254130.232.89.255510
46130.232.90.0/23130.232.90.1 to 130.232.91.254130.232.91.255510
47130.232.92.0/23130.232.92.1 to 130.232.93.254130.232.93.255510
48130.232.94.0/23130.232.94.1 to 130.232.95.254130.232.95.255510
49130.232.96.0/23130.232.96.1 to 130.232.97.254130.232.97.255510
50130.232.98.0/23130.232.98.1 to 130.232.99.254130.232.99.255510
51130.232.100.0/23130.232.100.1 to 130.232.101.254130.232.101.255510
52130.232.102.0/23130.232.102.1 to 130.232.103.254130.232.103.255510
53130.232.104.0/23130.232.104.1 to 130.232.105.254130.232.105.255510
54130.232.106.0/23130.232.106.1 to 130.232.107.254130.232.107.255510
55130.232.108.0/23130.232.108.1 to 130.232.109.254130.232.109.255510
56130.232.110.0/23130.232.110.1 to 130.232.111.254130.232.111.255510
57130.232.112.0/23130.232.112.1 to 130.232.113.254130.232.113.255510
58130.232.114.0/23130.232.114.1 to 130.232.115.254130.232.115.255510
59130.232.116.0/23130.232.116.1 to 130.232.117.254130.232.117.255510
60130.232.118.0/23130.232.118.1 to 130.232.119.254130.232.119.255510
61130.232.120.0/23130.232.120.1 to 130.232.121.254130.232.121.255510
62130.232.122.0/23130.232.122.1 to 130.232.123.254130.232.123.255510
63130.232.124.0/23130.232.124.1 to 130.232.125.254130.232.125.255510
64130.232.126.0/23130.232.126.1 to 130.232.127.254130.232.127.255510
65130.232.128.0/23130.232.128.1 to 130.232.129.254130.232.129.255510
66130.232.130.0/23130.232.130.1 to 130.232.131.254130.232.131.255510
67130.232.132.0/23130.232.132.1 to 130.232.133.254130.232.133.255510
68130.232.134.0/23130.232.134.1 to 130.232.135.254130.232.135.255510
69130.232.136.0/23130.232.136.1 to 130.232.137.254130.232.137.255510
70130.232.138.0/23130.232.138.1 to 130.232.139.254130.232.139.255510
71130.232.140.0/23130.232.140.1 to 130.232.141.254130.232.141.255510
72130.232.142.0/23130.232.142.1 to 130.232.143.254130.232.143.255510
73130.232.144.0/23130.232.144.1 to 130.232.145.254130.232.145.255510
74130.232.146.0/23130.232.146.1 to 130.232.147.254130.232.147.255510
75130.232.148.0/23130.232.148.1 to 130.232.149.254130.232.149.255510
76130.232.150.0/23130.232.150.1 to 130.232.151.254130.232.151.255510
77130.232.152.0/23130.232.152.1 to 130.232.153.254130.232.153.255510
78130.232.154.0/23130.232.154.1 to 130.232.155.254130.232.155.255510
79130.232.156.0/23130.232.156.1 to 130.232.157.254130.232.157.255510
80130.232.158.0/23130.232.158.1 to 130.232.159.254130.232.159.255510
81130.232.160.0/23130.232.160.1 to 130.232.161.254130.232.161.255510
82130.232.162.0/23130.232.162.1 to 130.232.163.254130.232.163.255510
83130.232.164.0/23130.232.164.1 to 130.232.165.254130.232.165.255510
84130.232.166.0/23130.232.166.1 to 130.232.167.254130.232.167.255510
85130.232.168.0/23130.232.168.1 to 130.232.169.254130.232.169.255510
86130.232.170.0/23130.232.170.1 to 130.232.171.254130.232.171.255510
87130.232.172.0/23130.232.172.1 to 130.232.173.254130.232.173.255510
88130.232.174.0/23130.232.174.1 to 130.232.175.254130.232.175.255510
89130.232.176.0/23130.232.176.1 to 130.232.177.254130.232.177.255510
90130.232.178.0/23130.232.178.1 to 130.232.179.254130.232.179.255510
91130.232.180.0/23130.232.180.1 to 130.232.181.254130.232.181.255510
92130.232.182.0/23130.232.182.1 to 130.232.183.254130.232.183.255510
93130.232.184.0/23130.232.184.1 to 130.232.185.254130.232.185.255510
94130.232.186.0/23130.232.186.1 to 130.232.187.254130.232.187.255510
95130.232.188.0/23130.232.188.1 to 130.232.189.254130.232.189.255510
96130.232.190.0/23130.232.190.1 to 130.232.191.254130.232.191.255510
97130.232.192.0/23130.232.192.1 to 130.232.193.254130.232.193.255510
98130.232.194.0/23130.232.194.1 to 130.232.195.254130.232.195.255510
99130.232.196.0/23130.232.196.1 to 130.232.197.254130.232.197.255510
100130.232.198.0/23130.232.198.1 to 130.232.199.254130.232.199.255510
101130.232.200.0/23130.232.200.1 to 130.232.201.254130.232.201.255510
102130.232.202.0/23130.232.202.1 to 130.232.203.254130.232.203.255510
103130.232.204.0/23130.232.204.1 to 130.232.205.254130.232.205.255510
104130.232.206.0/23130.232.206.1 to 130.232.207.254130.232.207.255510
105130.232.208.0/23130.232.208.1 to 130.232.209.254130.232.209.255510
106130.232.210.0/23130.232.210.1 to 130.232.211.254130.232.211.255510
107130.232.212.0/23130.232.212.1 to 130.232.213.254130.232.213.255510
108130.232.214.0/23130.232.214.1 to 130.232.215.254130.232.215.255510
109130.232.216.0/23130.232.216.1 to 130.232.217.254130.232.217.255510
110130.232.218.0/23130.232.218.1 to 130.232.219.254130.232.219.255510
111130.232.220.0/23130.232.220.1 to 130.232.221.254130.232.221.255510
112130.232.222.0/23130.232.222.1 to 130.232.223.254130.232.223.255510
113130.232.224.0/23130.232.224.1 to 130.232.225.254130.232.225.255510
114130.232.226.0/23130.232.226.1 to 130.232.227.254130.232.227.255510
115130.232.228.0/23130.232.228.1 to 130.232.229.254130.232.229.255510
116130.232.230.0/23130.232.230.1 to 130.232.231.254130.232.231.255510
117130.232.232.0/23130.232.232.1 to 130.232.233.254130.232.233.255510
118130.232.234.0/23130.232.234.1 to 130.232.235.254130.232.235.255510
119130.232.236.0/23130.232.236.1 to 130.232.237.254130.232.237.255510
120130.232.238.0/23130.232.238.1 to 130.232.239.254130.232.239.255510
121130.232.240.0/23130.232.240.1 to 130.232.241.254130.232.241.255510
122130.232.242.0/23130.232.242.1 to 130.232.243.254130.232.243.255510
123130.232.244.0/23130.232.244.1 to 130.232.245.254130.232.245.255510
124130.232.246.0/23130.232.246.1 to 130.232.247.254130.232.247.255510
125130.232.248.0/23130.232.248.1 to 130.232.249.254130.232.249.255510
126130.232.250.0/23130.232.250.1 to 130.232.251.254130.232.251.255510
127130.232.252.0/23130.232.252.1 to 130.232.253.254130.232.253.255510
128130.232.254.0/23130.232.254.1 to 130.232.255.254130.232.255.255510
129130.233.0.0/23130.233.0.1 to 130.233.1.254130.233.1.255510
130130.233.2.0/23130.233.2.1 to 130.233.3.254130.233.3.255510
131130.233.4.0/23130.233.4.1 to 130.233.5.254130.233.5.255510
132130.233.6.0/23130.233.6.1 to 130.233.7.254130.233.7.255510
133130.233.8.0/23130.233.8.1 to 130.233.9.254130.233.9.255510
134130.233.10.0/23130.233.10.1 to 130.233.11.254130.233.11.255510
135130.233.12.0/23130.233.12.1 to 130.233.13.254130.233.13.255510
136130.233.14.0/23130.233.14.1 to 130.233.15.254130.233.15.255510
137130.233.16.0/23130.233.16.1 to 130.233.17.254130.233.17.255510
138130.233.18.0/23130.233.18.1 to 130.233.19.254130.233.19.255510
139130.233.20.0/23130.233.20.1 to 130.233.21.254130.233.21.255510
140130.233.22.0/23130.233.22.1 to 130.233.23.254130.233.23.255510
141130.233.24.0/23130.233.24.1 to 130.233.25.254130.233.25.255510
142130.233.26.0/23130.233.26.1 to 130.233.27.254130.233.27.255510
143130.233.28.0/23130.233.28.1 to 130.233.29.254130.233.29.255510
144130.233.30.0/23130.233.30.1 to 130.233.31.254130.233.31.255510
145130.233.32.0/23130.233.32.1 to 130.233.33.254130.233.33.255510
146130.233.34.0/23130.233.34.1 to 130.233.35.254130.233.35.255510
147130.233.36.0/23130.233.36.1 to 130.233.37.254130.233.37.255510
148130.233.38.0/23130.233.38.1 to 130.233.39.254130.233.39.255510
149130.233.40.0/23130.233.40.1 to 130.233.41.254130.233.41.255510
150130.233.42.0/23130.233.42.1 to 130.233.43.254130.233.43.255510
151130.233.44.0/23130.233.44.1 to 130.233.45.254130.233.45.255510
152130.233.46.0/23130.233.46.1 to 130.233.47.254130.233.47.255510
153130.233.48.0/23130.233.48.1 to 130.233.49.254130.233.49.255510
154130.233.50.0/23130.233.50.1 to 130.233.51.254130.233.51.255510
155130.233.52.0/23130.233.52.1 to 130.233.53.254130.233.53.255510
156130.233.54.0/23130.233.54.1 to 130.233.55.254130.233.55.255510
157130.233.56.0/23130.233.56.1 to 130.233.57.254130.233.57.255510
158130.233.58.0/23130.233.58.1 to 130.233.59.254130.233.59.255510
159130.233.60.0/23130.233.60.1 to 130.233.61.254130.233.61.255510
160130.233.62.0/23130.233.62.1 to 130.233.63.254130.233.63.255510
161130.233.64.0/23130.233.64.1 to 130.233.65.254130.233.65.255510
162130.233.66.0/23130.233.66.1 to 130.233.67.254130.233.67.255510
163130.233.68.0/23130.233.68.1 to 130.233.69.254130.233.69.255510
164130.233.70.0/23130.233.70.1 to 130.233.71.254130.233.71.255510
165130.233.72.0/23130.233.72.1 to 130.233.73.254130.233.73.255510
166130.233.74.0/23130.233.74.1 to 130.233.75.254130.233.75.255510
167130.233.76.0/23130.233.76.1 to 130.233.77.254130.233.77.255510
168130.233.78.0/23130.233.78.1 to 130.233.79.254130.233.79.255510
169130.233.80.0/23130.233.80.1 to 130.233.81.254130.233.81.255510
170130.233.82.0/23130.233.82.1 to 130.233.83.254130.233.83.255510
171130.233.84.0/23130.233.84.1 to 130.233.85.254130.233.85.255510
172130.233.86.0/23130.233.86.1 to 130.233.87.254130.233.87.255510
173130.233.88.0/23130.233.88.1 to 130.233.89.254130.233.89.255510
174130.233.90.0/23130.233.90.1 to 130.233.91.254130.233.91.255510
175130.233.92.0/23130.233.92.1 to 130.233.93.254130.233.93.255510
176130.233.94.0/23130.233.94.1 to 130.233.95.254130.233.95.255510
177130.233.96.0/23130.233.96.1 to 130.233.97.254130.233.97.255510
178130.233.98.0/23130.233.98.1 to 130.233.99.254130.233.99.255510
179130.233.100.0/23130.233.100.1 to 130.233.101.254130.233.101.255510
180130.233.102.0/23130.233.102.1 to 130.233.103.254130.233.103.255510
181130.233.104.0/23130.233.104.1 to 130.233.105.254130.233.105.255510
182130.233.106.0/23130.233.106.1 to 130.233.107.254130.233.107.255510
183130.233.108.0/23130.233.108.1 to 130.233.109.254130.233.109.255510
184130.233.110.0/23130.233.110.1 to 130.233.111.254130.233.111.255510
185130.233.112.0/23130.233.112.1 to 130.233.113.254130.233.113.255510
186130.233.114.0/23130.233.114.1 to 130.233.115.254130.233.115.255510
187130.233.116.0/23130.233.116.1 to 130.233.117.254130.233.117.255510
188130.233.118.0/23130.233.118.1 to 130.233.119.254130.233.119.255510
189130.233.120.0/23130.233.120.1 to 130.233.121.254130.233.121.255510
190130.233.122.0/23130.233.122.1 to 130.233.123.254130.233.123.255510
191130.233.124.0/23130.233.124.1 to 130.233.125.254130.233.125.255510
192130.233.126.0/23130.233.126.1 to 130.233.127.254130.233.127.255510
193130.233.128.0/23130.233.128.1 to 130.233.129.254130.233.129.255510
194130.233.130.0/23130.233.130.1 to 130.233.131.254130.233.131.255510
195130.233.132.0/23130.233.132.1 to 130.233.133.254130.233.133.255510
196130.233.134.0/23130.233.134.1 to 130.233.135.254130.233.135.255510
197130.233.136.0/23130.233.136.1 to 130.233.137.254130.233.137.255510
198130.233.138.0/23130.233.138.1 to 130.233.139.254130.233.139.255510
199130.233.140.0/23130.233.140.1 to 130.233.141.254130.233.141.255510
200130.233.142.0/23130.233.142.1 to 130.233.143.254130.233.143.255510
201130.233.144.0/23130.233.144.1 to 130.233.145.254130.233.145.255510
202130.233.146.0/23130.233.146.1 to 130.233.147.254130.233.147.255510
203130.233.148.0/23130.233.148.1 to 130.233.149.254130.233.149.255510
204130.233.150.0/23130.233.150.1 to 130.233.151.254130.233.151.255510
205130.233.152.0/23130.233.152.1 to 130.233.153.254130.233.153.255510
206130.233.154.0/23130.233.154.1 to 130.233.155.254130.233.155.255510
207130.233.156.0/23130.233.156.1 to 130.233.157.254130.233.157.255510
208130.233.158.0/23130.233.158.1 to 130.233.159.254130.233.159.255510
209130.233.160.0/23130.233.160.1 to 130.233.161.254130.233.161.255510
210130.233.162.0/23130.233.162.1 to 130.233.163.254130.233.163.255510
211130.233.164.0/23130.233.164.1 to 130.233.165.254130.233.165.255510
212130.233.166.0/23130.233.166.1 to 130.233.167.254130.233.167.255510
213130.233.168.0/23130.233.168.1 to 130.233.169.254130.233.169.255510
214130.233.170.0/23130.233.170.1 to 130.233.171.254130.233.171.255510
215130.233.172.0/23130.233.172.1 to 130.233.173.254130.233.173.255510
216130.233.174.0/23130.233.174.1 to 130.233.175.254130.233.175.255510
217130.233.176.0/23130.233.176.1 to 130.233.177.254130.233.177.255510
218130.233.178.0/23130.233.178.1 to 130.233.179.254130.233.179.255510
219130.233.180.0/23130.233.180.1 to 130.233.181.254130.233.181.255510
220130.233.182.0/23130.233.182.1 to 130.233.183.254130.233.183.255510
221130.233.184.0/23130.233.184.1 to 130.233.185.254130.233.185.255510
222130.233.186.0/23130.233.186.1 to 130.233.187.254130.233.187.255510
223130.233.188.0/23130.233.188.1 to 130.233.189.254130.233.189.255510
224130.233.190.0/23130.233.190.1 to 130.233.191.254130.233.191.255510
225130.233.192.0/23130.233.192.1 to 130.233.193.254130.233.193.255510
226130.233.194.0/23130.233.194.1 to 130.233.195.254130.233.195.255510
227130.233.196.0/23130.233.196.1 to 130.233.197.254130.233.197.255510
228130.233.198.0/23130.233.198.1 to 130.233.199.254130.233.199.255510
229130.233.200.0/23130.233.200.1 to 130.233.201.254130.233.201.255510
230130.233.202.0/23130.233.202.1 to 130.233.203.254130.233.203.255510
231130.233.204.0/23130.233.204.1 to 130.233.205.254130.233.205.255510
232130.233.206.0/23130.233.206.1 to 130.233.207.254130.233.207.255510
233130.233.208.0/23130.233.208.1 to 130.233.209.254130.233.209.255510
234130.233.210.0/23130.233.210.1 to 130.233.211.254130.233.211.255510
235130.233.212.0/23130.233.212.1 to 130.233.213.254130.233.213.255510
236130.233.214.0/23130.233.214.1 to 130.233.215.254130.233.215.255510
237130.233.216.0/23130.233.216.1 to 130.233.217.254130.233.217.255510
238130.233.218.0/23130.233.218.1 to 130.233.219.254130.233.219.255510
239130.233.220.0/23130.233.220.1 to 130.233.221.254130.233.221.255510
240130.233.222.0/23130.233.222.1 to 130.233.223.254130.233.223.255510
241130.233.224.0/23130.233.224.1 to 130.233.225.254130.233.225.255510
242130.233.226.0/23130.233.226.1 to 130.233.227.254130.233.227.255510
243130.233.228.0/23130.233.228.1 to 130.233.229.254130.233.229.255510
244130.233.230.0/23130.233.230.1 to 130.233.231.254130.233.231.255510
245130.233.232.0/23130.233.232.1 to 130.233.233.254130.233.233.255510
246130.233.234.0/23130.233.234.1 to 130.233.235.254130.233.235.255510
247130.233.236.0/23130.233.236.1 to 130.233.237.254130.233.237.255510
248130.233.238.0/23130.233.238.1 to 130.233.239.254130.233.239.255510
249130.233.240.0/23130.233.240.1 to 130.233.241.254130.233.241.255510
250130.233.242.0/23130.233.242.1 to 130.233.243.254130.233.243.255510
251130.233.244.0/23130.233.244.1 to 130.233.245.254130.233.245.255510
252130.233.246.0/23130.233.246.1 to 130.233.247.254130.233.247.255510
253130.233.248.0/23130.233.248.1 to 130.233.249.254130.233.249.255510
254130.233.250.0/23130.233.250.1 to 130.233.251.254130.233.251.255510
255130.233.252.0/23130.233.252.1 to 130.233.253.254130.233.253.255510
256130.233.254.0/23130.233.254.1 to 130.233.255.254130.233.255.255510

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.