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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.

Network202.112.0.0/12
Usable hosts1,048,574
Subnet mask255.240.0.0
Addresses1,048,576
Network address
202.112.0.0
Broadcast address
202.127.255.255
First usable
202.112.0.1
Last usable
202.127.255.254
Usable hosts
1,048,574 (1,048,576 less the network and broadcast addresses)
Subnet mask
255.240.0.0
Wildcard mask
0.15.255.255 (Cisco ACLs, OSPF)
Prefix length
/12
Type
Public public
Old class
C (default /24)
As numbers
Hex CA700000 · Integer 3396337664 to 3397386239
Reverse DNS zones
112.202.in-addr.arpa
113.202.in-addr.arpa
114.202.in-addr.arpa
115.202.in-addr.arpa
116.202.in-addr.arpa
117.202.in-addr.arpa
118.202.in-addr.arpa
119.202.in-addr.arpa
120.202.in-addr.arpa
121.202.in-addr.arpa
122.202.in-addr.arpa
123.202.in-addr.arpa
124.202.in-addr.arpa
125.202.in-addr.arpa
126.202.in-addr.arpa
127.202.in-addr.arpa
/12 is not on a 8-bit boundary, so it takes 16 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11001010.01110000.00000000.00000000202.112.0.0
Subnet mask11111111.11110000.00000000.00000000255.240.0.0
Network11001010.01110000.00000000.00000000202.112.0.0
Broadcast11001010.01111111.11111111.11111111202.127.255.255
Split into smaller subnets/22
/13 (2)/14 (4)/15 (8)/16 (16)/17 (32)/18 (64)/19 (128)/20 (256)/21 (512)/22 (1,024)/23 (2,048)/24 (4,096)

202.112.0.0/12 makes 1,024 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1202.112.0.0/22202.112.0.1 to 202.112.3.254202.112.3.2551,022
2202.112.4.0/22202.112.4.1 to 202.112.7.254202.112.7.2551,022
3202.112.8.0/22202.112.8.1 to 202.112.11.254202.112.11.2551,022
4202.112.12.0/22202.112.12.1 to 202.112.15.254202.112.15.2551,022
5202.112.16.0/22202.112.16.1 to 202.112.19.254202.112.19.2551,022
6202.112.20.0/22202.112.20.1 to 202.112.23.254202.112.23.2551,022
7202.112.24.0/22202.112.24.1 to 202.112.27.254202.112.27.2551,022
8202.112.28.0/22202.112.28.1 to 202.112.31.254202.112.31.2551,022
9202.112.32.0/22202.112.32.1 to 202.112.35.254202.112.35.2551,022
10202.112.36.0/22202.112.36.1 to 202.112.39.254202.112.39.2551,022
11202.112.40.0/22202.112.40.1 to 202.112.43.254202.112.43.2551,022
12202.112.44.0/22202.112.44.1 to 202.112.47.254202.112.47.2551,022
13202.112.48.0/22202.112.48.1 to 202.112.51.254202.112.51.2551,022
14202.112.52.0/22202.112.52.1 to 202.112.55.254202.112.55.2551,022
15202.112.56.0/22202.112.56.1 to 202.112.59.254202.112.59.2551,022
16202.112.60.0/22202.112.60.1 to 202.112.63.254202.112.63.2551,022
17202.112.64.0/22202.112.64.1 to 202.112.67.254202.112.67.2551,022
18202.112.68.0/22202.112.68.1 to 202.112.71.254202.112.71.2551,022
19202.112.72.0/22202.112.72.1 to 202.112.75.254202.112.75.2551,022
20202.112.76.0/22202.112.76.1 to 202.112.79.254202.112.79.2551,022
21202.112.80.0/22202.112.80.1 to 202.112.83.254202.112.83.2551,022
22202.112.84.0/22202.112.84.1 to 202.112.87.254202.112.87.2551,022
23202.112.88.0/22202.112.88.1 to 202.112.91.254202.112.91.2551,022
24202.112.92.0/22202.112.92.1 to 202.112.95.254202.112.95.2551,022
25202.112.96.0/22202.112.96.1 to 202.112.99.254202.112.99.2551,022
26202.112.100.0/22202.112.100.1 to 202.112.103.254202.112.103.2551,022
27202.112.104.0/22202.112.104.1 to 202.112.107.254202.112.107.2551,022
28202.112.108.0/22202.112.108.1 to 202.112.111.254202.112.111.2551,022
29202.112.112.0/22202.112.112.1 to 202.112.115.254202.112.115.2551,022
30202.112.116.0/22202.112.116.1 to 202.112.119.254202.112.119.2551,022
31202.112.120.0/22202.112.120.1 to 202.112.123.254202.112.123.2551,022
32202.112.124.0/22202.112.124.1 to 202.112.127.254202.112.127.2551,022
33202.112.128.0/22202.112.128.1 to 202.112.131.254202.112.131.2551,022
34202.112.132.0/22202.112.132.1 to 202.112.135.254202.112.135.2551,022
35202.112.136.0/22202.112.136.1 to 202.112.139.254202.112.139.2551,022
36202.112.140.0/22202.112.140.1 to 202.112.143.254202.112.143.2551,022
37202.112.144.0/22202.112.144.1 to 202.112.147.254202.112.147.2551,022
38202.112.148.0/22202.112.148.1 to 202.112.151.254202.112.151.2551,022
39202.112.152.0/22202.112.152.1 to 202.112.155.254202.112.155.2551,022
40202.112.156.0/22202.112.156.1 to 202.112.159.254202.112.159.2551,022
41202.112.160.0/22202.112.160.1 to 202.112.163.254202.112.163.2551,022
42202.112.164.0/22202.112.164.1 to 202.112.167.254202.112.167.2551,022
43202.112.168.0/22202.112.168.1 to 202.112.171.254202.112.171.2551,022
44202.112.172.0/22202.112.172.1 to 202.112.175.254202.112.175.2551,022
45202.112.176.0/22202.112.176.1 to 202.112.179.254202.112.179.2551,022
46202.112.180.0/22202.112.180.1 to 202.112.183.254202.112.183.2551,022
47202.112.184.0/22202.112.184.1 to 202.112.187.254202.112.187.2551,022
48202.112.188.0/22202.112.188.1 to 202.112.191.254202.112.191.2551,022
49202.112.192.0/22202.112.192.1 to 202.112.195.254202.112.195.2551,022
50202.112.196.0/22202.112.196.1 to 202.112.199.254202.112.199.2551,022
51202.112.200.0/22202.112.200.1 to 202.112.203.254202.112.203.2551,022
52202.112.204.0/22202.112.204.1 to 202.112.207.254202.112.207.2551,022
53202.112.208.0/22202.112.208.1 to 202.112.211.254202.112.211.2551,022
54202.112.212.0/22202.112.212.1 to 202.112.215.254202.112.215.2551,022
55202.112.216.0/22202.112.216.1 to 202.112.219.254202.112.219.2551,022
56202.112.220.0/22202.112.220.1 to 202.112.223.254202.112.223.2551,022
57202.112.224.0/22202.112.224.1 to 202.112.227.254202.112.227.2551,022
58202.112.228.0/22202.112.228.1 to 202.112.231.254202.112.231.2551,022
59202.112.232.0/22202.112.232.1 to 202.112.235.254202.112.235.2551,022
60202.112.236.0/22202.112.236.1 to 202.112.239.254202.112.239.2551,022
61202.112.240.0/22202.112.240.1 to 202.112.243.254202.112.243.2551,022
62202.112.244.0/22202.112.244.1 to 202.112.247.254202.112.247.2551,022
63202.112.248.0/22202.112.248.1 to 202.112.251.254202.112.251.2551,022
64202.112.252.0/22202.112.252.1 to 202.112.255.254202.112.255.2551,022
65202.113.0.0/22202.113.0.1 to 202.113.3.254202.113.3.2551,022
66202.113.4.0/22202.113.4.1 to 202.113.7.254202.113.7.2551,022
67202.113.8.0/22202.113.8.1 to 202.113.11.254202.113.11.2551,022
68202.113.12.0/22202.113.12.1 to 202.113.15.254202.113.15.2551,022
69202.113.16.0/22202.113.16.1 to 202.113.19.254202.113.19.2551,022
70202.113.20.0/22202.113.20.1 to 202.113.23.254202.113.23.2551,022
71202.113.24.0/22202.113.24.1 to 202.113.27.254202.113.27.2551,022
72202.113.28.0/22202.113.28.1 to 202.113.31.254202.113.31.2551,022
73202.113.32.0/22202.113.32.1 to 202.113.35.254202.113.35.2551,022
74202.113.36.0/22202.113.36.1 to 202.113.39.254202.113.39.2551,022
75202.113.40.0/22202.113.40.1 to 202.113.43.254202.113.43.2551,022
76202.113.44.0/22202.113.44.1 to 202.113.47.254202.113.47.2551,022
77202.113.48.0/22202.113.48.1 to 202.113.51.254202.113.51.2551,022
78202.113.52.0/22202.113.52.1 to 202.113.55.254202.113.55.2551,022
79202.113.56.0/22202.113.56.1 to 202.113.59.254202.113.59.2551,022
80202.113.60.0/22202.113.60.1 to 202.113.63.254202.113.63.2551,022
81202.113.64.0/22202.113.64.1 to 202.113.67.254202.113.67.2551,022
82202.113.68.0/22202.113.68.1 to 202.113.71.254202.113.71.2551,022
83202.113.72.0/22202.113.72.1 to 202.113.75.254202.113.75.2551,022
84202.113.76.0/22202.113.76.1 to 202.113.79.254202.113.79.2551,022
85202.113.80.0/22202.113.80.1 to 202.113.83.254202.113.83.2551,022
86202.113.84.0/22202.113.84.1 to 202.113.87.254202.113.87.2551,022
87202.113.88.0/22202.113.88.1 to 202.113.91.254202.113.91.2551,022
88202.113.92.0/22202.113.92.1 to 202.113.95.254202.113.95.2551,022
89202.113.96.0/22202.113.96.1 to 202.113.99.254202.113.99.2551,022
90202.113.100.0/22202.113.100.1 to 202.113.103.254202.113.103.2551,022
91202.113.104.0/22202.113.104.1 to 202.113.107.254202.113.107.2551,022
92202.113.108.0/22202.113.108.1 to 202.113.111.254202.113.111.2551,022
93202.113.112.0/22202.113.112.1 to 202.113.115.254202.113.115.2551,022
94202.113.116.0/22202.113.116.1 to 202.113.119.254202.113.119.2551,022
95202.113.120.0/22202.113.120.1 to 202.113.123.254202.113.123.2551,022
96202.113.124.0/22202.113.124.1 to 202.113.127.254202.113.127.2551,022
97202.113.128.0/22202.113.128.1 to 202.113.131.254202.113.131.2551,022
98202.113.132.0/22202.113.132.1 to 202.113.135.254202.113.135.2551,022
99202.113.136.0/22202.113.136.1 to 202.113.139.254202.113.139.2551,022
100202.113.140.0/22202.113.140.1 to 202.113.143.254202.113.143.2551,022
101202.113.144.0/22202.113.144.1 to 202.113.147.254202.113.147.2551,022
102202.113.148.0/22202.113.148.1 to 202.113.151.254202.113.151.2551,022
103202.113.152.0/22202.113.152.1 to 202.113.155.254202.113.155.2551,022
104202.113.156.0/22202.113.156.1 to 202.113.159.254202.113.159.2551,022
105202.113.160.0/22202.113.160.1 to 202.113.163.254202.113.163.2551,022
106202.113.164.0/22202.113.164.1 to 202.113.167.254202.113.167.2551,022
107202.113.168.0/22202.113.168.1 to 202.113.171.254202.113.171.2551,022
108202.113.172.0/22202.113.172.1 to 202.113.175.254202.113.175.2551,022
109202.113.176.0/22202.113.176.1 to 202.113.179.254202.113.179.2551,022
110202.113.180.0/22202.113.180.1 to 202.113.183.254202.113.183.2551,022
111202.113.184.0/22202.113.184.1 to 202.113.187.254202.113.187.2551,022
112202.113.188.0/22202.113.188.1 to 202.113.191.254202.113.191.2551,022
113202.113.192.0/22202.113.192.1 to 202.113.195.254202.113.195.2551,022
114202.113.196.0/22202.113.196.1 to 202.113.199.254202.113.199.2551,022
115202.113.200.0/22202.113.200.1 to 202.113.203.254202.113.203.2551,022
116202.113.204.0/22202.113.204.1 to 202.113.207.254202.113.207.2551,022
117202.113.208.0/22202.113.208.1 to 202.113.211.254202.113.211.2551,022
118202.113.212.0/22202.113.212.1 to 202.113.215.254202.113.215.2551,022
119202.113.216.0/22202.113.216.1 to 202.113.219.254202.113.219.2551,022
120202.113.220.0/22202.113.220.1 to 202.113.223.254202.113.223.2551,022
121202.113.224.0/22202.113.224.1 to 202.113.227.254202.113.227.2551,022
122202.113.228.0/22202.113.228.1 to 202.113.231.254202.113.231.2551,022
123202.113.232.0/22202.113.232.1 to 202.113.235.254202.113.235.2551,022
124202.113.236.0/22202.113.236.1 to 202.113.239.254202.113.239.2551,022
125202.113.240.0/22202.113.240.1 to 202.113.243.254202.113.243.2551,022
126202.113.244.0/22202.113.244.1 to 202.113.247.254202.113.247.2551,022
127202.113.248.0/22202.113.248.1 to 202.113.251.254202.113.251.2551,022
128202.113.252.0/22202.113.252.1 to 202.113.255.254202.113.255.2551,022
129202.114.0.0/22202.114.0.1 to 202.114.3.254202.114.3.2551,022
130202.114.4.0/22202.114.4.1 to 202.114.7.254202.114.7.2551,022
131202.114.8.0/22202.114.8.1 to 202.114.11.254202.114.11.2551,022
132202.114.12.0/22202.114.12.1 to 202.114.15.254202.114.15.2551,022
133202.114.16.0/22202.114.16.1 to 202.114.19.254202.114.19.2551,022
134202.114.20.0/22202.114.20.1 to 202.114.23.254202.114.23.2551,022
135202.114.24.0/22202.114.24.1 to 202.114.27.254202.114.27.2551,022
136202.114.28.0/22202.114.28.1 to 202.114.31.254202.114.31.2551,022
137202.114.32.0/22202.114.32.1 to 202.114.35.254202.114.35.2551,022
138202.114.36.0/22202.114.36.1 to 202.114.39.254202.114.39.2551,022
139202.114.40.0/22202.114.40.1 to 202.114.43.254202.114.43.2551,022
140202.114.44.0/22202.114.44.1 to 202.114.47.254202.114.47.2551,022
141202.114.48.0/22202.114.48.1 to 202.114.51.254202.114.51.2551,022
142202.114.52.0/22202.114.52.1 to 202.114.55.254202.114.55.2551,022
143202.114.56.0/22202.114.56.1 to 202.114.59.254202.114.59.2551,022
144202.114.60.0/22202.114.60.1 to 202.114.63.254202.114.63.2551,022
145202.114.64.0/22202.114.64.1 to 202.114.67.254202.114.67.2551,022
146202.114.68.0/22202.114.68.1 to 202.114.71.254202.114.71.2551,022
147202.114.72.0/22202.114.72.1 to 202.114.75.254202.114.75.2551,022
148202.114.76.0/22202.114.76.1 to 202.114.79.254202.114.79.2551,022
149202.114.80.0/22202.114.80.1 to 202.114.83.254202.114.83.2551,022
150202.114.84.0/22202.114.84.1 to 202.114.87.254202.114.87.2551,022
151202.114.88.0/22202.114.88.1 to 202.114.91.254202.114.91.2551,022
152202.114.92.0/22202.114.92.1 to 202.114.95.254202.114.95.2551,022
153202.114.96.0/22202.114.96.1 to 202.114.99.254202.114.99.2551,022
154202.114.100.0/22202.114.100.1 to 202.114.103.254202.114.103.2551,022
155202.114.104.0/22202.114.104.1 to 202.114.107.254202.114.107.2551,022
156202.114.108.0/22202.114.108.1 to 202.114.111.254202.114.111.2551,022
157202.114.112.0/22202.114.112.1 to 202.114.115.254202.114.115.2551,022
158202.114.116.0/22202.114.116.1 to 202.114.119.254202.114.119.2551,022
159202.114.120.0/22202.114.120.1 to 202.114.123.254202.114.123.2551,022
160202.114.124.0/22202.114.124.1 to 202.114.127.254202.114.127.2551,022
161202.114.128.0/22202.114.128.1 to 202.114.131.254202.114.131.2551,022
162202.114.132.0/22202.114.132.1 to 202.114.135.254202.114.135.2551,022
163202.114.136.0/22202.114.136.1 to 202.114.139.254202.114.139.2551,022
164202.114.140.0/22202.114.140.1 to 202.114.143.254202.114.143.2551,022
165202.114.144.0/22202.114.144.1 to 202.114.147.254202.114.147.2551,022
166202.114.148.0/22202.114.148.1 to 202.114.151.254202.114.151.2551,022
167202.114.152.0/22202.114.152.1 to 202.114.155.254202.114.155.2551,022
168202.114.156.0/22202.114.156.1 to 202.114.159.254202.114.159.2551,022
169202.114.160.0/22202.114.160.1 to 202.114.163.254202.114.163.2551,022
170202.114.164.0/22202.114.164.1 to 202.114.167.254202.114.167.2551,022
171202.114.168.0/22202.114.168.1 to 202.114.171.254202.114.171.2551,022
172202.114.172.0/22202.114.172.1 to 202.114.175.254202.114.175.2551,022
173202.114.176.0/22202.114.176.1 to 202.114.179.254202.114.179.2551,022
174202.114.180.0/22202.114.180.1 to 202.114.183.254202.114.183.2551,022
175202.114.184.0/22202.114.184.1 to 202.114.187.254202.114.187.2551,022
176202.114.188.0/22202.114.188.1 to 202.114.191.254202.114.191.2551,022
177202.114.192.0/22202.114.192.1 to 202.114.195.254202.114.195.2551,022
178202.114.196.0/22202.114.196.1 to 202.114.199.254202.114.199.2551,022
179202.114.200.0/22202.114.200.1 to 202.114.203.254202.114.203.2551,022
180202.114.204.0/22202.114.204.1 to 202.114.207.254202.114.207.2551,022
181202.114.208.0/22202.114.208.1 to 202.114.211.254202.114.211.2551,022
182202.114.212.0/22202.114.212.1 to 202.114.215.254202.114.215.2551,022
183202.114.216.0/22202.114.216.1 to 202.114.219.254202.114.219.2551,022
184202.114.220.0/22202.114.220.1 to 202.114.223.254202.114.223.2551,022
185202.114.224.0/22202.114.224.1 to 202.114.227.254202.114.227.2551,022
186202.114.228.0/22202.114.228.1 to 202.114.231.254202.114.231.2551,022
187202.114.232.0/22202.114.232.1 to 202.114.235.254202.114.235.2551,022
188202.114.236.0/22202.114.236.1 to 202.114.239.254202.114.239.2551,022
189202.114.240.0/22202.114.240.1 to 202.114.243.254202.114.243.2551,022
190202.114.244.0/22202.114.244.1 to 202.114.247.254202.114.247.2551,022
191202.114.248.0/22202.114.248.1 to 202.114.251.254202.114.251.2551,022
192202.114.252.0/22202.114.252.1 to 202.114.255.254202.114.255.2551,022
193202.115.0.0/22202.115.0.1 to 202.115.3.254202.115.3.2551,022
194202.115.4.0/22202.115.4.1 to 202.115.7.254202.115.7.2551,022
195202.115.8.0/22202.115.8.1 to 202.115.11.254202.115.11.2551,022
196202.115.12.0/22202.115.12.1 to 202.115.15.254202.115.15.2551,022
197202.115.16.0/22202.115.16.1 to 202.115.19.254202.115.19.2551,022
198202.115.20.0/22202.115.20.1 to 202.115.23.254202.115.23.2551,022
199202.115.24.0/22202.115.24.1 to 202.115.27.254202.115.27.2551,022
200202.115.28.0/22202.115.28.1 to 202.115.31.254202.115.31.2551,022
201202.115.32.0/22202.115.32.1 to 202.115.35.254202.115.35.2551,022
202202.115.36.0/22202.115.36.1 to 202.115.39.254202.115.39.2551,022
203202.115.40.0/22202.115.40.1 to 202.115.43.254202.115.43.2551,022
204202.115.44.0/22202.115.44.1 to 202.115.47.254202.115.47.2551,022
205202.115.48.0/22202.115.48.1 to 202.115.51.254202.115.51.2551,022
206202.115.52.0/22202.115.52.1 to 202.115.55.254202.115.55.2551,022
207202.115.56.0/22202.115.56.1 to 202.115.59.254202.115.59.2551,022
208202.115.60.0/22202.115.60.1 to 202.115.63.254202.115.63.2551,022
209202.115.64.0/22202.115.64.1 to 202.115.67.254202.115.67.2551,022
210202.115.68.0/22202.115.68.1 to 202.115.71.254202.115.71.2551,022
211202.115.72.0/22202.115.72.1 to 202.115.75.254202.115.75.2551,022
212202.115.76.0/22202.115.76.1 to 202.115.79.254202.115.79.2551,022
213202.115.80.0/22202.115.80.1 to 202.115.83.254202.115.83.2551,022
214202.115.84.0/22202.115.84.1 to 202.115.87.254202.115.87.2551,022
215202.115.88.0/22202.115.88.1 to 202.115.91.254202.115.91.2551,022
216202.115.92.0/22202.115.92.1 to 202.115.95.254202.115.95.2551,022
217202.115.96.0/22202.115.96.1 to 202.115.99.254202.115.99.2551,022
218202.115.100.0/22202.115.100.1 to 202.115.103.254202.115.103.2551,022
219202.115.104.0/22202.115.104.1 to 202.115.107.254202.115.107.2551,022
220202.115.108.0/22202.115.108.1 to 202.115.111.254202.115.111.2551,022
221202.115.112.0/22202.115.112.1 to 202.115.115.254202.115.115.2551,022
222202.115.116.0/22202.115.116.1 to 202.115.119.254202.115.119.2551,022
223202.115.120.0/22202.115.120.1 to 202.115.123.254202.115.123.2551,022
224202.115.124.0/22202.115.124.1 to 202.115.127.254202.115.127.2551,022
225202.115.128.0/22202.115.128.1 to 202.115.131.254202.115.131.2551,022
226202.115.132.0/22202.115.132.1 to 202.115.135.254202.115.135.2551,022
227202.115.136.0/22202.115.136.1 to 202.115.139.254202.115.139.2551,022
228202.115.140.0/22202.115.140.1 to 202.115.143.254202.115.143.2551,022
229202.115.144.0/22202.115.144.1 to 202.115.147.254202.115.147.2551,022
230202.115.148.0/22202.115.148.1 to 202.115.151.254202.115.151.2551,022
231202.115.152.0/22202.115.152.1 to 202.115.155.254202.115.155.2551,022
232202.115.156.0/22202.115.156.1 to 202.115.159.254202.115.159.2551,022
233202.115.160.0/22202.115.160.1 to 202.115.163.254202.115.163.2551,022
234202.115.164.0/22202.115.164.1 to 202.115.167.254202.115.167.2551,022
235202.115.168.0/22202.115.168.1 to 202.115.171.254202.115.171.2551,022
236202.115.172.0/22202.115.172.1 to 202.115.175.254202.115.175.2551,022
237202.115.176.0/22202.115.176.1 to 202.115.179.254202.115.179.2551,022
238202.115.180.0/22202.115.180.1 to 202.115.183.254202.115.183.2551,022
239202.115.184.0/22202.115.184.1 to 202.115.187.254202.115.187.2551,022
240202.115.188.0/22202.115.188.1 to 202.115.191.254202.115.191.2551,022
241202.115.192.0/22202.115.192.1 to 202.115.195.254202.115.195.2551,022
242202.115.196.0/22202.115.196.1 to 202.115.199.254202.115.199.2551,022
243202.115.200.0/22202.115.200.1 to 202.115.203.254202.115.203.2551,022
244202.115.204.0/22202.115.204.1 to 202.115.207.254202.115.207.2551,022
245202.115.208.0/22202.115.208.1 to 202.115.211.254202.115.211.2551,022
246202.115.212.0/22202.115.212.1 to 202.115.215.254202.115.215.2551,022
247202.115.216.0/22202.115.216.1 to 202.115.219.254202.115.219.2551,022
248202.115.220.0/22202.115.220.1 to 202.115.223.254202.115.223.2551,022
249202.115.224.0/22202.115.224.1 to 202.115.227.254202.115.227.2551,022
250202.115.228.0/22202.115.228.1 to 202.115.231.254202.115.231.2551,022
251202.115.232.0/22202.115.232.1 to 202.115.235.254202.115.235.2551,022
252202.115.236.0/22202.115.236.1 to 202.115.239.254202.115.239.2551,022
253202.115.240.0/22202.115.240.1 to 202.115.243.254202.115.243.2551,022
254202.115.244.0/22202.115.244.1 to 202.115.247.254202.115.247.2551,022
255202.115.248.0/22202.115.248.1 to 202.115.251.254202.115.251.2551,022
256202.115.252.0/22202.115.252.1 to 202.115.255.254202.115.255.2551,022

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.