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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.

Network124.80.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
124.80.0.0
Broadcast address
124.87.255.255
First usable
124.80.0.1
Last usable
124.87.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 7C500000 · Integer 2085617664 to 2086141951
Reverse DNS zones
80.124.in-addr.arpa
81.124.in-addr.arpa
82.124.in-addr.arpa
83.124.in-addr.arpa
84.124.in-addr.arpa
85.124.in-addr.arpa
86.124.in-addr.arpa
87.124.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01111100.01010000.00000000.00000000124.80.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01111100.01010000.00000000.00000000124.80.0.0
Broadcast01111100.01010111.11111111.11111111124.87.255.255
Split into smaller subnets/22
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

124.80.0.0/13 makes 512 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1124.80.0.0/22124.80.0.1 to 124.80.3.254124.80.3.2551,022
2124.80.4.0/22124.80.4.1 to 124.80.7.254124.80.7.2551,022
3124.80.8.0/22124.80.8.1 to 124.80.11.254124.80.11.2551,022
4124.80.12.0/22124.80.12.1 to 124.80.15.254124.80.15.2551,022
5124.80.16.0/22124.80.16.1 to 124.80.19.254124.80.19.2551,022
6124.80.20.0/22124.80.20.1 to 124.80.23.254124.80.23.2551,022
7124.80.24.0/22124.80.24.1 to 124.80.27.254124.80.27.2551,022
8124.80.28.0/22124.80.28.1 to 124.80.31.254124.80.31.2551,022
9124.80.32.0/22124.80.32.1 to 124.80.35.254124.80.35.2551,022
10124.80.36.0/22124.80.36.1 to 124.80.39.254124.80.39.2551,022
11124.80.40.0/22124.80.40.1 to 124.80.43.254124.80.43.2551,022
12124.80.44.0/22124.80.44.1 to 124.80.47.254124.80.47.2551,022
13124.80.48.0/22124.80.48.1 to 124.80.51.254124.80.51.2551,022
14124.80.52.0/22124.80.52.1 to 124.80.55.254124.80.55.2551,022
15124.80.56.0/22124.80.56.1 to 124.80.59.254124.80.59.2551,022
16124.80.60.0/22124.80.60.1 to 124.80.63.254124.80.63.2551,022
17124.80.64.0/22124.80.64.1 to 124.80.67.254124.80.67.2551,022
18124.80.68.0/22124.80.68.1 to 124.80.71.254124.80.71.2551,022
19124.80.72.0/22124.80.72.1 to 124.80.75.254124.80.75.2551,022
20124.80.76.0/22124.80.76.1 to 124.80.79.254124.80.79.2551,022
21124.80.80.0/22124.80.80.1 to 124.80.83.254124.80.83.2551,022
22124.80.84.0/22124.80.84.1 to 124.80.87.254124.80.87.2551,022
23124.80.88.0/22124.80.88.1 to 124.80.91.254124.80.91.2551,022
24124.80.92.0/22124.80.92.1 to 124.80.95.254124.80.95.2551,022
25124.80.96.0/22124.80.96.1 to 124.80.99.254124.80.99.2551,022
26124.80.100.0/22124.80.100.1 to 124.80.103.254124.80.103.2551,022
27124.80.104.0/22124.80.104.1 to 124.80.107.254124.80.107.2551,022
28124.80.108.0/22124.80.108.1 to 124.80.111.254124.80.111.2551,022
29124.80.112.0/22124.80.112.1 to 124.80.115.254124.80.115.2551,022
30124.80.116.0/22124.80.116.1 to 124.80.119.254124.80.119.2551,022
31124.80.120.0/22124.80.120.1 to 124.80.123.254124.80.123.2551,022
32124.80.124.0/22124.80.124.1 to 124.80.127.254124.80.127.2551,022
33124.80.128.0/22124.80.128.1 to 124.80.131.254124.80.131.2551,022
34124.80.132.0/22124.80.132.1 to 124.80.135.254124.80.135.2551,022
35124.80.136.0/22124.80.136.1 to 124.80.139.254124.80.139.2551,022
36124.80.140.0/22124.80.140.1 to 124.80.143.254124.80.143.2551,022
37124.80.144.0/22124.80.144.1 to 124.80.147.254124.80.147.2551,022
38124.80.148.0/22124.80.148.1 to 124.80.151.254124.80.151.2551,022
39124.80.152.0/22124.80.152.1 to 124.80.155.254124.80.155.2551,022
40124.80.156.0/22124.80.156.1 to 124.80.159.254124.80.159.2551,022
41124.80.160.0/22124.80.160.1 to 124.80.163.254124.80.163.2551,022
42124.80.164.0/22124.80.164.1 to 124.80.167.254124.80.167.2551,022
43124.80.168.0/22124.80.168.1 to 124.80.171.254124.80.171.2551,022
44124.80.172.0/22124.80.172.1 to 124.80.175.254124.80.175.2551,022
45124.80.176.0/22124.80.176.1 to 124.80.179.254124.80.179.2551,022
46124.80.180.0/22124.80.180.1 to 124.80.183.254124.80.183.2551,022
47124.80.184.0/22124.80.184.1 to 124.80.187.254124.80.187.2551,022
48124.80.188.0/22124.80.188.1 to 124.80.191.254124.80.191.2551,022
49124.80.192.0/22124.80.192.1 to 124.80.195.254124.80.195.2551,022
50124.80.196.0/22124.80.196.1 to 124.80.199.254124.80.199.2551,022
51124.80.200.0/22124.80.200.1 to 124.80.203.254124.80.203.2551,022
52124.80.204.0/22124.80.204.1 to 124.80.207.254124.80.207.2551,022
53124.80.208.0/22124.80.208.1 to 124.80.211.254124.80.211.2551,022
54124.80.212.0/22124.80.212.1 to 124.80.215.254124.80.215.2551,022
55124.80.216.0/22124.80.216.1 to 124.80.219.254124.80.219.2551,022
56124.80.220.0/22124.80.220.1 to 124.80.223.254124.80.223.2551,022
57124.80.224.0/22124.80.224.1 to 124.80.227.254124.80.227.2551,022
58124.80.228.0/22124.80.228.1 to 124.80.231.254124.80.231.2551,022
59124.80.232.0/22124.80.232.1 to 124.80.235.254124.80.235.2551,022
60124.80.236.0/22124.80.236.1 to 124.80.239.254124.80.239.2551,022
61124.80.240.0/22124.80.240.1 to 124.80.243.254124.80.243.2551,022
62124.80.244.0/22124.80.244.1 to 124.80.247.254124.80.247.2551,022
63124.80.248.0/22124.80.248.1 to 124.80.251.254124.80.251.2551,022
64124.80.252.0/22124.80.252.1 to 124.80.255.254124.80.255.2551,022
65124.81.0.0/22124.81.0.1 to 124.81.3.254124.81.3.2551,022
66124.81.4.0/22124.81.4.1 to 124.81.7.254124.81.7.2551,022
67124.81.8.0/22124.81.8.1 to 124.81.11.254124.81.11.2551,022
68124.81.12.0/22124.81.12.1 to 124.81.15.254124.81.15.2551,022
69124.81.16.0/22124.81.16.1 to 124.81.19.254124.81.19.2551,022
70124.81.20.0/22124.81.20.1 to 124.81.23.254124.81.23.2551,022
71124.81.24.0/22124.81.24.1 to 124.81.27.254124.81.27.2551,022
72124.81.28.0/22124.81.28.1 to 124.81.31.254124.81.31.2551,022
73124.81.32.0/22124.81.32.1 to 124.81.35.254124.81.35.2551,022
74124.81.36.0/22124.81.36.1 to 124.81.39.254124.81.39.2551,022
75124.81.40.0/22124.81.40.1 to 124.81.43.254124.81.43.2551,022
76124.81.44.0/22124.81.44.1 to 124.81.47.254124.81.47.2551,022
77124.81.48.0/22124.81.48.1 to 124.81.51.254124.81.51.2551,022
78124.81.52.0/22124.81.52.1 to 124.81.55.254124.81.55.2551,022
79124.81.56.0/22124.81.56.1 to 124.81.59.254124.81.59.2551,022
80124.81.60.0/22124.81.60.1 to 124.81.63.254124.81.63.2551,022
81124.81.64.0/22124.81.64.1 to 124.81.67.254124.81.67.2551,022
82124.81.68.0/22124.81.68.1 to 124.81.71.254124.81.71.2551,022
83124.81.72.0/22124.81.72.1 to 124.81.75.254124.81.75.2551,022
84124.81.76.0/22124.81.76.1 to 124.81.79.254124.81.79.2551,022
85124.81.80.0/22124.81.80.1 to 124.81.83.254124.81.83.2551,022
86124.81.84.0/22124.81.84.1 to 124.81.87.254124.81.87.2551,022
87124.81.88.0/22124.81.88.1 to 124.81.91.254124.81.91.2551,022
88124.81.92.0/22124.81.92.1 to 124.81.95.254124.81.95.2551,022
89124.81.96.0/22124.81.96.1 to 124.81.99.254124.81.99.2551,022
90124.81.100.0/22124.81.100.1 to 124.81.103.254124.81.103.2551,022
91124.81.104.0/22124.81.104.1 to 124.81.107.254124.81.107.2551,022
92124.81.108.0/22124.81.108.1 to 124.81.111.254124.81.111.2551,022
93124.81.112.0/22124.81.112.1 to 124.81.115.254124.81.115.2551,022
94124.81.116.0/22124.81.116.1 to 124.81.119.254124.81.119.2551,022
95124.81.120.0/22124.81.120.1 to 124.81.123.254124.81.123.2551,022
96124.81.124.0/22124.81.124.1 to 124.81.127.254124.81.127.2551,022
97124.81.128.0/22124.81.128.1 to 124.81.131.254124.81.131.2551,022
98124.81.132.0/22124.81.132.1 to 124.81.135.254124.81.135.2551,022
99124.81.136.0/22124.81.136.1 to 124.81.139.254124.81.139.2551,022
100124.81.140.0/22124.81.140.1 to 124.81.143.254124.81.143.2551,022
101124.81.144.0/22124.81.144.1 to 124.81.147.254124.81.147.2551,022
102124.81.148.0/22124.81.148.1 to 124.81.151.254124.81.151.2551,022
103124.81.152.0/22124.81.152.1 to 124.81.155.254124.81.155.2551,022
104124.81.156.0/22124.81.156.1 to 124.81.159.254124.81.159.2551,022
105124.81.160.0/22124.81.160.1 to 124.81.163.254124.81.163.2551,022
106124.81.164.0/22124.81.164.1 to 124.81.167.254124.81.167.2551,022
107124.81.168.0/22124.81.168.1 to 124.81.171.254124.81.171.2551,022
108124.81.172.0/22124.81.172.1 to 124.81.175.254124.81.175.2551,022
109124.81.176.0/22124.81.176.1 to 124.81.179.254124.81.179.2551,022
110124.81.180.0/22124.81.180.1 to 124.81.183.254124.81.183.2551,022
111124.81.184.0/22124.81.184.1 to 124.81.187.254124.81.187.2551,022
112124.81.188.0/22124.81.188.1 to 124.81.191.254124.81.191.2551,022
113124.81.192.0/22124.81.192.1 to 124.81.195.254124.81.195.2551,022
114124.81.196.0/22124.81.196.1 to 124.81.199.254124.81.199.2551,022
115124.81.200.0/22124.81.200.1 to 124.81.203.254124.81.203.2551,022
116124.81.204.0/22124.81.204.1 to 124.81.207.254124.81.207.2551,022
117124.81.208.0/22124.81.208.1 to 124.81.211.254124.81.211.2551,022
118124.81.212.0/22124.81.212.1 to 124.81.215.254124.81.215.2551,022
119124.81.216.0/22124.81.216.1 to 124.81.219.254124.81.219.2551,022
120124.81.220.0/22124.81.220.1 to 124.81.223.254124.81.223.2551,022
121124.81.224.0/22124.81.224.1 to 124.81.227.254124.81.227.2551,022
122124.81.228.0/22124.81.228.1 to 124.81.231.254124.81.231.2551,022
123124.81.232.0/22124.81.232.1 to 124.81.235.254124.81.235.2551,022
124124.81.236.0/22124.81.236.1 to 124.81.239.254124.81.239.2551,022
125124.81.240.0/22124.81.240.1 to 124.81.243.254124.81.243.2551,022
126124.81.244.0/22124.81.244.1 to 124.81.247.254124.81.247.2551,022
127124.81.248.0/22124.81.248.1 to 124.81.251.254124.81.251.2551,022
128124.81.252.0/22124.81.252.1 to 124.81.255.254124.81.255.2551,022
129124.82.0.0/22124.82.0.1 to 124.82.3.254124.82.3.2551,022
130124.82.4.0/22124.82.4.1 to 124.82.7.254124.82.7.2551,022
131124.82.8.0/22124.82.8.1 to 124.82.11.254124.82.11.2551,022
132124.82.12.0/22124.82.12.1 to 124.82.15.254124.82.15.2551,022
133124.82.16.0/22124.82.16.1 to 124.82.19.254124.82.19.2551,022
134124.82.20.0/22124.82.20.1 to 124.82.23.254124.82.23.2551,022
135124.82.24.0/22124.82.24.1 to 124.82.27.254124.82.27.2551,022
136124.82.28.0/22124.82.28.1 to 124.82.31.254124.82.31.2551,022
137124.82.32.0/22124.82.32.1 to 124.82.35.254124.82.35.2551,022
138124.82.36.0/22124.82.36.1 to 124.82.39.254124.82.39.2551,022
139124.82.40.0/22124.82.40.1 to 124.82.43.254124.82.43.2551,022
140124.82.44.0/22124.82.44.1 to 124.82.47.254124.82.47.2551,022
141124.82.48.0/22124.82.48.1 to 124.82.51.254124.82.51.2551,022
142124.82.52.0/22124.82.52.1 to 124.82.55.254124.82.55.2551,022
143124.82.56.0/22124.82.56.1 to 124.82.59.254124.82.59.2551,022
144124.82.60.0/22124.82.60.1 to 124.82.63.254124.82.63.2551,022
145124.82.64.0/22124.82.64.1 to 124.82.67.254124.82.67.2551,022
146124.82.68.0/22124.82.68.1 to 124.82.71.254124.82.71.2551,022
147124.82.72.0/22124.82.72.1 to 124.82.75.254124.82.75.2551,022
148124.82.76.0/22124.82.76.1 to 124.82.79.254124.82.79.2551,022
149124.82.80.0/22124.82.80.1 to 124.82.83.254124.82.83.2551,022
150124.82.84.0/22124.82.84.1 to 124.82.87.254124.82.87.2551,022
151124.82.88.0/22124.82.88.1 to 124.82.91.254124.82.91.2551,022
152124.82.92.0/22124.82.92.1 to 124.82.95.254124.82.95.2551,022
153124.82.96.0/22124.82.96.1 to 124.82.99.254124.82.99.2551,022
154124.82.100.0/22124.82.100.1 to 124.82.103.254124.82.103.2551,022
155124.82.104.0/22124.82.104.1 to 124.82.107.254124.82.107.2551,022
156124.82.108.0/22124.82.108.1 to 124.82.111.254124.82.111.2551,022
157124.82.112.0/22124.82.112.1 to 124.82.115.254124.82.115.2551,022
158124.82.116.0/22124.82.116.1 to 124.82.119.254124.82.119.2551,022
159124.82.120.0/22124.82.120.1 to 124.82.123.254124.82.123.2551,022
160124.82.124.0/22124.82.124.1 to 124.82.127.254124.82.127.2551,022
161124.82.128.0/22124.82.128.1 to 124.82.131.254124.82.131.2551,022
162124.82.132.0/22124.82.132.1 to 124.82.135.254124.82.135.2551,022
163124.82.136.0/22124.82.136.1 to 124.82.139.254124.82.139.2551,022
164124.82.140.0/22124.82.140.1 to 124.82.143.254124.82.143.2551,022
165124.82.144.0/22124.82.144.1 to 124.82.147.254124.82.147.2551,022
166124.82.148.0/22124.82.148.1 to 124.82.151.254124.82.151.2551,022
167124.82.152.0/22124.82.152.1 to 124.82.155.254124.82.155.2551,022
168124.82.156.0/22124.82.156.1 to 124.82.159.254124.82.159.2551,022
169124.82.160.0/22124.82.160.1 to 124.82.163.254124.82.163.2551,022
170124.82.164.0/22124.82.164.1 to 124.82.167.254124.82.167.2551,022
171124.82.168.0/22124.82.168.1 to 124.82.171.254124.82.171.2551,022
172124.82.172.0/22124.82.172.1 to 124.82.175.254124.82.175.2551,022
173124.82.176.0/22124.82.176.1 to 124.82.179.254124.82.179.2551,022
174124.82.180.0/22124.82.180.1 to 124.82.183.254124.82.183.2551,022
175124.82.184.0/22124.82.184.1 to 124.82.187.254124.82.187.2551,022
176124.82.188.0/22124.82.188.1 to 124.82.191.254124.82.191.2551,022
177124.82.192.0/22124.82.192.1 to 124.82.195.254124.82.195.2551,022
178124.82.196.0/22124.82.196.1 to 124.82.199.254124.82.199.2551,022
179124.82.200.0/22124.82.200.1 to 124.82.203.254124.82.203.2551,022
180124.82.204.0/22124.82.204.1 to 124.82.207.254124.82.207.2551,022
181124.82.208.0/22124.82.208.1 to 124.82.211.254124.82.211.2551,022
182124.82.212.0/22124.82.212.1 to 124.82.215.254124.82.215.2551,022
183124.82.216.0/22124.82.216.1 to 124.82.219.254124.82.219.2551,022
184124.82.220.0/22124.82.220.1 to 124.82.223.254124.82.223.2551,022
185124.82.224.0/22124.82.224.1 to 124.82.227.254124.82.227.2551,022
186124.82.228.0/22124.82.228.1 to 124.82.231.254124.82.231.2551,022
187124.82.232.0/22124.82.232.1 to 124.82.235.254124.82.235.2551,022
188124.82.236.0/22124.82.236.1 to 124.82.239.254124.82.239.2551,022
189124.82.240.0/22124.82.240.1 to 124.82.243.254124.82.243.2551,022
190124.82.244.0/22124.82.244.1 to 124.82.247.254124.82.247.2551,022
191124.82.248.0/22124.82.248.1 to 124.82.251.254124.82.251.2551,022
192124.82.252.0/22124.82.252.1 to 124.82.255.254124.82.255.2551,022
193124.83.0.0/22124.83.0.1 to 124.83.3.254124.83.3.2551,022
194124.83.4.0/22124.83.4.1 to 124.83.7.254124.83.7.2551,022
195124.83.8.0/22124.83.8.1 to 124.83.11.254124.83.11.2551,022
196124.83.12.0/22124.83.12.1 to 124.83.15.254124.83.15.2551,022
197124.83.16.0/22124.83.16.1 to 124.83.19.254124.83.19.2551,022
198124.83.20.0/22124.83.20.1 to 124.83.23.254124.83.23.2551,022
199124.83.24.0/22124.83.24.1 to 124.83.27.254124.83.27.2551,022
200124.83.28.0/22124.83.28.1 to 124.83.31.254124.83.31.2551,022
201124.83.32.0/22124.83.32.1 to 124.83.35.254124.83.35.2551,022
202124.83.36.0/22124.83.36.1 to 124.83.39.254124.83.39.2551,022
203124.83.40.0/22124.83.40.1 to 124.83.43.254124.83.43.2551,022
204124.83.44.0/22124.83.44.1 to 124.83.47.254124.83.47.2551,022
205124.83.48.0/22124.83.48.1 to 124.83.51.254124.83.51.2551,022
206124.83.52.0/22124.83.52.1 to 124.83.55.254124.83.55.2551,022
207124.83.56.0/22124.83.56.1 to 124.83.59.254124.83.59.2551,022
208124.83.60.0/22124.83.60.1 to 124.83.63.254124.83.63.2551,022
209124.83.64.0/22124.83.64.1 to 124.83.67.254124.83.67.2551,022
210124.83.68.0/22124.83.68.1 to 124.83.71.254124.83.71.2551,022
211124.83.72.0/22124.83.72.1 to 124.83.75.254124.83.75.2551,022
212124.83.76.0/22124.83.76.1 to 124.83.79.254124.83.79.2551,022
213124.83.80.0/22124.83.80.1 to 124.83.83.254124.83.83.2551,022
214124.83.84.0/22124.83.84.1 to 124.83.87.254124.83.87.2551,022
215124.83.88.0/22124.83.88.1 to 124.83.91.254124.83.91.2551,022
216124.83.92.0/22124.83.92.1 to 124.83.95.254124.83.95.2551,022
217124.83.96.0/22124.83.96.1 to 124.83.99.254124.83.99.2551,022
218124.83.100.0/22124.83.100.1 to 124.83.103.254124.83.103.2551,022
219124.83.104.0/22124.83.104.1 to 124.83.107.254124.83.107.2551,022
220124.83.108.0/22124.83.108.1 to 124.83.111.254124.83.111.2551,022
221124.83.112.0/22124.83.112.1 to 124.83.115.254124.83.115.2551,022
222124.83.116.0/22124.83.116.1 to 124.83.119.254124.83.119.2551,022
223124.83.120.0/22124.83.120.1 to 124.83.123.254124.83.123.2551,022
224124.83.124.0/22124.83.124.1 to 124.83.127.254124.83.127.2551,022
225124.83.128.0/22124.83.128.1 to 124.83.131.254124.83.131.2551,022
226124.83.132.0/22124.83.132.1 to 124.83.135.254124.83.135.2551,022
227124.83.136.0/22124.83.136.1 to 124.83.139.254124.83.139.2551,022
228124.83.140.0/22124.83.140.1 to 124.83.143.254124.83.143.2551,022
229124.83.144.0/22124.83.144.1 to 124.83.147.254124.83.147.2551,022
230124.83.148.0/22124.83.148.1 to 124.83.151.254124.83.151.2551,022
231124.83.152.0/22124.83.152.1 to 124.83.155.254124.83.155.2551,022
232124.83.156.0/22124.83.156.1 to 124.83.159.254124.83.159.2551,022
233124.83.160.0/22124.83.160.1 to 124.83.163.254124.83.163.2551,022
234124.83.164.0/22124.83.164.1 to 124.83.167.254124.83.167.2551,022
235124.83.168.0/22124.83.168.1 to 124.83.171.254124.83.171.2551,022
236124.83.172.0/22124.83.172.1 to 124.83.175.254124.83.175.2551,022
237124.83.176.0/22124.83.176.1 to 124.83.179.254124.83.179.2551,022
238124.83.180.0/22124.83.180.1 to 124.83.183.254124.83.183.2551,022
239124.83.184.0/22124.83.184.1 to 124.83.187.254124.83.187.2551,022
240124.83.188.0/22124.83.188.1 to 124.83.191.254124.83.191.2551,022
241124.83.192.0/22124.83.192.1 to 124.83.195.254124.83.195.2551,022
242124.83.196.0/22124.83.196.1 to 124.83.199.254124.83.199.2551,022
243124.83.200.0/22124.83.200.1 to 124.83.203.254124.83.203.2551,022
244124.83.204.0/22124.83.204.1 to 124.83.207.254124.83.207.2551,022
245124.83.208.0/22124.83.208.1 to 124.83.211.254124.83.211.2551,022
246124.83.212.0/22124.83.212.1 to 124.83.215.254124.83.215.2551,022
247124.83.216.0/22124.83.216.1 to 124.83.219.254124.83.219.2551,022
248124.83.220.0/22124.83.220.1 to 124.83.223.254124.83.223.2551,022
249124.83.224.0/22124.83.224.1 to 124.83.227.254124.83.227.2551,022
250124.83.228.0/22124.83.228.1 to 124.83.231.254124.83.231.2551,022
251124.83.232.0/22124.83.232.1 to 124.83.235.254124.83.235.2551,022
252124.83.236.0/22124.83.236.1 to 124.83.239.254124.83.239.2551,022
253124.83.240.0/22124.83.240.1 to 124.83.243.254124.83.243.2551,022
254124.83.244.0/22124.83.244.1 to 124.83.247.254124.83.247.2551,022
255124.83.248.0/22124.83.248.1 to 124.83.251.254124.83.251.2551,022
256124.83.252.0/22124.83.252.1 to 124.83.255.254124.83.255.2551,022

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.