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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.

Network45.192.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
45.192.0.0
Broadcast address
45.255.255.255
First usable
45.192.0.1
Last usable
45.255.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 2DC00000 · Integer 767557632 to 771751935
Reverse DNS zones
192.45.in-addr.arpa
193.45.in-addr.arpa
194.45.in-addr.arpa
195.45.in-addr.arpa
196.45.in-addr.arpa
197.45.in-addr.arpa
198.45.in-addr.arpa
199.45.in-addr.arpa
200.45.in-addr.arpa
201.45.in-addr.arpa
202.45.in-addr.arpa
203.45.in-addr.arpa
204.45.in-addr.arpa
205.45.in-addr.arpa
206.45.in-addr.arpa
207.45.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101101.11000000.00000000.0000000045.192.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00101101.11000000.00000000.0000000045.192.0.0
Broadcast00101101.11111111.11111111.1111111145.255.255.255
Split into smaller subnets/22
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

45.192.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
145.192.0.0/2245.192.0.1 to 45.192.3.25445.192.3.2551,022
245.192.4.0/2245.192.4.1 to 45.192.7.25445.192.7.2551,022
345.192.8.0/2245.192.8.1 to 45.192.11.25445.192.11.2551,022
445.192.12.0/2245.192.12.1 to 45.192.15.25445.192.15.2551,022
545.192.16.0/2245.192.16.1 to 45.192.19.25445.192.19.2551,022
645.192.20.0/2245.192.20.1 to 45.192.23.25445.192.23.2551,022
745.192.24.0/2245.192.24.1 to 45.192.27.25445.192.27.2551,022
845.192.28.0/2245.192.28.1 to 45.192.31.25445.192.31.2551,022
945.192.32.0/2245.192.32.1 to 45.192.35.25445.192.35.2551,022
1045.192.36.0/2245.192.36.1 to 45.192.39.25445.192.39.2551,022
1145.192.40.0/2245.192.40.1 to 45.192.43.25445.192.43.2551,022
1245.192.44.0/2245.192.44.1 to 45.192.47.25445.192.47.2551,022
1345.192.48.0/2245.192.48.1 to 45.192.51.25445.192.51.2551,022
1445.192.52.0/2245.192.52.1 to 45.192.55.25445.192.55.2551,022
1545.192.56.0/2245.192.56.1 to 45.192.59.25445.192.59.2551,022
1645.192.60.0/2245.192.60.1 to 45.192.63.25445.192.63.2551,022
1745.192.64.0/2245.192.64.1 to 45.192.67.25445.192.67.2551,022
1845.192.68.0/2245.192.68.1 to 45.192.71.25445.192.71.2551,022
1945.192.72.0/2245.192.72.1 to 45.192.75.25445.192.75.2551,022
2045.192.76.0/2245.192.76.1 to 45.192.79.25445.192.79.2551,022
2145.192.80.0/2245.192.80.1 to 45.192.83.25445.192.83.2551,022
2245.192.84.0/2245.192.84.1 to 45.192.87.25445.192.87.2551,022
2345.192.88.0/2245.192.88.1 to 45.192.91.25445.192.91.2551,022
2445.192.92.0/2245.192.92.1 to 45.192.95.25445.192.95.2551,022
2545.192.96.0/2245.192.96.1 to 45.192.99.25445.192.99.2551,022
2645.192.100.0/2245.192.100.1 to 45.192.103.25445.192.103.2551,022
2745.192.104.0/2245.192.104.1 to 45.192.107.25445.192.107.2551,022
2845.192.108.0/2245.192.108.1 to 45.192.111.25445.192.111.2551,022
2945.192.112.0/2245.192.112.1 to 45.192.115.25445.192.115.2551,022
3045.192.116.0/2245.192.116.1 to 45.192.119.25445.192.119.2551,022
3145.192.120.0/2245.192.120.1 to 45.192.123.25445.192.123.2551,022
3245.192.124.0/2245.192.124.1 to 45.192.127.25445.192.127.2551,022
3345.192.128.0/2245.192.128.1 to 45.192.131.25445.192.131.2551,022
3445.192.132.0/2245.192.132.1 to 45.192.135.25445.192.135.2551,022
3545.192.136.0/2245.192.136.1 to 45.192.139.25445.192.139.2551,022
3645.192.140.0/2245.192.140.1 to 45.192.143.25445.192.143.2551,022
3745.192.144.0/2245.192.144.1 to 45.192.147.25445.192.147.2551,022
3845.192.148.0/2245.192.148.1 to 45.192.151.25445.192.151.2551,022
3945.192.152.0/2245.192.152.1 to 45.192.155.25445.192.155.2551,022
4045.192.156.0/2245.192.156.1 to 45.192.159.25445.192.159.2551,022
4145.192.160.0/2245.192.160.1 to 45.192.163.25445.192.163.2551,022
4245.192.164.0/2245.192.164.1 to 45.192.167.25445.192.167.2551,022
4345.192.168.0/2245.192.168.1 to 45.192.171.25445.192.171.2551,022
4445.192.172.0/2245.192.172.1 to 45.192.175.25445.192.175.2551,022
4545.192.176.0/2245.192.176.1 to 45.192.179.25445.192.179.2551,022
4645.192.180.0/2245.192.180.1 to 45.192.183.25445.192.183.2551,022
4745.192.184.0/2245.192.184.1 to 45.192.187.25445.192.187.2551,022
4845.192.188.0/2245.192.188.1 to 45.192.191.25445.192.191.2551,022
4945.192.192.0/2245.192.192.1 to 45.192.195.25445.192.195.2551,022
5045.192.196.0/2245.192.196.1 to 45.192.199.25445.192.199.2551,022
5145.192.200.0/2245.192.200.1 to 45.192.203.25445.192.203.2551,022
5245.192.204.0/2245.192.204.1 to 45.192.207.25445.192.207.2551,022
5345.192.208.0/2245.192.208.1 to 45.192.211.25445.192.211.2551,022
5445.192.212.0/2245.192.212.1 to 45.192.215.25445.192.215.2551,022
5545.192.216.0/2245.192.216.1 to 45.192.219.25445.192.219.2551,022
5645.192.220.0/2245.192.220.1 to 45.192.223.25445.192.223.2551,022
5745.192.224.0/2245.192.224.1 to 45.192.227.25445.192.227.2551,022
5845.192.228.0/2245.192.228.1 to 45.192.231.25445.192.231.2551,022
5945.192.232.0/2245.192.232.1 to 45.192.235.25445.192.235.2551,022
6045.192.236.0/2245.192.236.1 to 45.192.239.25445.192.239.2551,022
6145.192.240.0/2245.192.240.1 to 45.192.243.25445.192.243.2551,022
6245.192.244.0/2245.192.244.1 to 45.192.247.25445.192.247.2551,022
6345.192.248.0/2245.192.248.1 to 45.192.251.25445.192.251.2551,022
6445.192.252.0/2245.192.252.1 to 45.192.255.25445.192.255.2551,022
6545.193.0.0/2245.193.0.1 to 45.193.3.25445.193.3.2551,022
6645.193.4.0/2245.193.4.1 to 45.193.7.25445.193.7.2551,022
6745.193.8.0/2245.193.8.1 to 45.193.11.25445.193.11.2551,022
6845.193.12.0/2245.193.12.1 to 45.193.15.25445.193.15.2551,022
6945.193.16.0/2245.193.16.1 to 45.193.19.25445.193.19.2551,022
7045.193.20.0/2245.193.20.1 to 45.193.23.25445.193.23.2551,022
7145.193.24.0/2245.193.24.1 to 45.193.27.25445.193.27.2551,022
7245.193.28.0/2245.193.28.1 to 45.193.31.25445.193.31.2551,022
7345.193.32.0/2245.193.32.1 to 45.193.35.25445.193.35.2551,022
7445.193.36.0/2245.193.36.1 to 45.193.39.25445.193.39.2551,022
7545.193.40.0/2245.193.40.1 to 45.193.43.25445.193.43.2551,022
7645.193.44.0/2245.193.44.1 to 45.193.47.25445.193.47.2551,022
7745.193.48.0/2245.193.48.1 to 45.193.51.25445.193.51.2551,022
7845.193.52.0/2245.193.52.1 to 45.193.55.25445.193.55.2551,022
7945.193.56.0/2245.193.56.1 to 45.193.59.25445.193.59.2551,022
8045.193.60.0/2245.193.60.1 to 45.193.63.25445.193.63.2551,022
8145.193.64.0/2245.193.64.1 to 45.193.67.25445.193.67.2551,022
8245.193.68.0/2245.193.68.1 to 45.193.71.25445.193.71.2551,022
8345.193.72.0/2245.193.72.1 to 45.193.75.25445.193.75.2551,022
8445.193.76.0/2245.193.76.1 to 45.193.79.25445.193.79.2551,022
8545.193.80.0/2245.193.80.1 to 45.193.83.25445.193.83.2551,022
8645.193.84.0/2245.193.84.1 to 45.193.87.25445.193.87.2551,022
8745.193.88.0/2245.193.88.1 to 45.193.91.25445.193.91.2551,022
8845.193.92.0/2245.193.92.1 to 45.193.95.25445.193.95.2551,022
8945.193.96.0/2245.193.96.1 to 45.193.99.25445.193.99.2551,022
9045.193.100.0/2245.193.100.1 to 45.193.103.25445.193.103.2551,022
9145.193.104.0/2245.193.104.1 to 45.193.107.25445.193.107.2551,022
9245.193.108.0/2245.193.108.1 to 45.193.111.25445.193.111.2551,022
9345.193.112.0/2245.193.112.1 to 45.193.115.25445.193.115.2551,022
9445.193.116.0/2245.193.116.1 to 45.193.119.25445.193.119.2551,022
9545.193.120.0/2245.193.120.1 to 45.193.123.25445.193.123.2551,022
9645.193.124.0/2245.193.124.1 to 45.193.127.25445.193.127.2551,022
9745.193.128.0/2245.193.128.1 to 45.193.131.25445.193.131.2551,022
9845.193.132.0/2245.193.132.1 to 45.193.135.25445.193.135.2551,022
9945.193.136.0/2245.193.136.1 to 45.193.139.25445.193.139.2551,022
10045.193.140.0/2245.193.140.1 to 45.193.143.25445.193.143.2551,022
10145.193.144.0/2245.193.144.1 to 45.193.147.25445.193.147.2551,022
10245.193.148.0/2245.193.148.1 to 45.193.151.25445.193.151.2551,022
10345.193.152.0/2245.193.152.1 to 45.193.155.25445.193.155.2551,022
10445.193.156.0/2245.193.156.1 to 45.193.159.25445.193.159.2551,022
10545.193.160.0/2245.193.160.1 to 45.193.163.25445.193.163.2551,022
10645.193.164.0/2245.193.164.1 to 45.193.167.25445.193.167.2551,022
10745.193.168.0/2245.193.168.1 to 45.193.171.25445.193.171.2551,022
10845.193.172.0/2245.193.172.1 to 45.193.175.25445.193.175.2551,022
10945.193.176.0/2245.193.176.1 to 45.193.179.25445.193.179.2551,022
11045.193.180.0/2245.193.180.1 to 45.193.183.25445.193.183.2551,022
11145.193.184.0/2245.193.184.1 to 45.193.187.25445.193.187.2551,022
11245.193.188.0/2245.193.188.1 to 45.193.191.25445.193.191.2551,022
11345.193.192.0/2245.193.192.1 to 45.193.195.25445.193.195.2551,022
11445.193.196.0/2245.193.196.1 to 45.193.199.25445.193.199.2551,022
11545.193.200.0/2245.193.200.1 to 45.193.203.25445.193.203.2551,022
11645.193.204.0/2245.193.204.1 to 45.193.207.25445.193.207.2551,022
11745.193.208.0/2245.193.208.1 to 45.193.211.25445.193.211.2551,022
11845.193.212.0/2245.193.212.1 to 45.193.215.25445.193.215.2551,022
11945.193.216.0/2245.193.216.1 to 45.193.219.25445.193.219.2551,022
12045.193.220.0/2245.193.220.1 to 45.193.223.25445.193.223.2551,022
12145.193.224.0/2245.193.224.1 to 45.193.227.25445.193.227.2551,022
12245.193.228.0/2245.193.228.1 to 45.193.231.25445.193.231.2551,022
12345.193.232.0/2245.193.232.1 to 45.193.235.25445.193.235.2551,022
12445.193.236.0/2245.193.236.1 to 45.193.239.25445.193.239.2551,022
12545.193.240.0/2245.193.240.1 to 45.193.243.25445.193.243.2551,022
12645.193.244.0/2245.193.244.1 to 45.193.247.25445.193.247.2551,022
12745.193.248.0/2245.193.248.1 to 45.193.251.25445.193.251.2551,022
12845.193.252.0/2245.193.252.1 to 45.193.255.25445.193.255.2551,022
12945.194.0.0/2245.194.0.1 to 45.194.3.25445.194.3.2551,022
13045.194.4.0/2245.194.4.1 to 45.194.7.25445.194.7.2551,022
13145.194.8.0/2245.194.8.1 to 45.194.11.25445.194.11.2551,022
13245.194.12.0/2245.194.12.1 to 45.194.15.25445.194.15.2551,022
13345.194.16.0/2245.194.16.1 to 45.194.19.25445.194.19.2551,022
13445.194.20.0/2245.194.20.1 to 45.194.23.25445.194.23.2551,022
13545.194.24.0/2245.194.24.1 to 45.194.27.25445.194.27.2551,022
13645.194.28.0/2245.194.28.1 to 45.194.31.25445.194.31.2551,022
13745.194.32.0/2245.194.32.1 to 45.194.35.25445.194.35.2551,022
13845.194.36.0/2245.194.36.1 to 45.194.39.25445.194.39.2551,022
13945.194.40.0/2245.194.40.1 to 45.194.43.25445.194.43.2551,022
14045.194.44.0/2245.194.44.1 to 45.194.47.25445.194.47.2551,022
14145.194.48.0/2245.194.48.1 to 45.194.51.25445.194.51.2551,022
14245.194.52.0/2245.194.52.1 to 45.194.55.25445.194.55.2551,022
14345.194.56.0/2245.194.56.1 to 45.194.59.25445.194.59.2551,022
14445.194.60.0/2245.194.60.1 to 45.194.63.25445.194.63.2551,022
14545.194.64.0/2245.194.64.1 to 45.194.67.25445.194.67.2551,022
14645.194.68.0/2245.194.68.1 to 45.194.71.25445.194.71.2551,022
14745.194.72.0/2245.194.72.1 to 45.194.75.25445.194.75.2551,022
14845.194.76.0/2245.194.76.1 to 45.194.79.25445.194.79.2551,022
14945.194.80.0/2245.194.80.1 to 45.194.83.25445.194.83.2551,022
15045.194.84.0/2245.194.84.1 to 45.194.87.25445.194.87.2551,022
15145.194.88.0/2245.194.88.1 to 45.194.91.25445.194.91.2551,022
15245.194.92.0/2245.194.92.1 to 45.194.95.25445.194.95.2551,022
15345.194.96.0/2245.194.96.1 to 45.194.99.25445.194.99.2551,022
15445.194.100.0/2245.194.100.1 to 45.194.103.25445.194.103.2551,022
15545.194.104.0/2245.194.104.1 to 45.194.107.25445.194.107.2551,022
15645.194.108.0/2245.194.108.1 to 45.194.111.25445.194.111.2551,022
15745.194.112.0/2245.194.112.1 to 45.194.115.25445.194.115.2551,022
15845.194.116.0/2245.194.116.1 to 45.194.119.25445.194.119.2551,022
15945.194.120.0/2245.194.120.1 to 45.194.123.25445.194.123.2551,022
16045.194.124.0/2245.194.124.1 to 45.194.127.25445.194.127.2551,022
16145.194.128.0/2245.194.128.1 to 45.194.131.25445.194.131.2551,022
16245.194.132.0/2245.194.132.1 to 45.194.135.25445.194.135.2551,022
16345.194.136.0/2245.194.136.1 to 45.194.139.25445.194.139.2551,022
16445.194.140.0/2245.194.140.1 to 45.194.143.25445.194.143.2551,022
16545.194.144.0/2245.194.144.1 to 45.194.147.25445.194.147.2551,022
16645.194.148.0/2245.194.148.1 to 45.194.151.25445.194.151.2551,022
16745.194.152.0/2245.194.152.1 to 45.194.155.25445.194.155.2551,022
16845.194.156.0/2245.194.156.1 to 45.194.159.25445.194.159.2551,022
16945.194.160.0/2245.194.160.1 to 45.194.163.25445.194.163.2551,022
17045.194.164.0/2245.194.164.1 to 45.194.167.25445.194.167.2551,022
17145.194.168.0/2245.194.168.1 to 45.194.171.25445.194.171.2551,022
17245.194.172.0/2245.194.172.1 to 45.194.175.25445.194.175.2551,022
17345.194.176.0/2245.194.176.1 to 45.194.179.25445.194.179.2551,022
17445.194.180.0/2245.194.180.1 to 45.194.183.25445.194.183.2551,022
17545.194.184.0/2245.194.184.1 to 45.194.187.25445.194.187.2551,022
17645.194.188.0/2245.194.188.1 to 45.194.191.25445.194.191.2551,022
17745.194.192.0/2245.194.192.1 to 45.194.195.25445.194.195.2551,022
17845.194.196.0/2245.194.196.1 to 45.194.199.25445.194.199.2551,022
17945.194.200.0/2245.194.200.1 to 45.194.203.25445.194.203.2551,022
18045.194.204.0/2245.194.204.1 to 45.194.207.25445.194.207.2551,022
18145.194.208.0/2245.194.208.1 to 45.194.211.25445.194.211.2551,022
18245.194.212.0/2245.194.212.1 to 45.194.215.25445.194.215.2551,022
18345.194.216.0/2245.194.216.1 to 45.194.219.25445.194.219.2551,022
18445.194.220.0/2245.194.220.1 to 45.194.223.25445.194.223.2551,022
18545.194.224.0/2245.194.224.1 to 45.194.227.25445.194.227.2551,022
18645.194.228.0/2245.194.228.1 to 45.194.231.25445.194.231.2551,022
18745.194.232.0/2245.194.232.1 to 45.194.235.25445.194.235.2551,022
18845.194.236.0/2245.194.236.1 to 45.194.239.25445.194.239.2551,022
18945.194.240.0/2245.194.240.1 to 45.194.243.25445.194.243.2551,022
19045.194.244.0/2245.194.244.1 to 45.194.247.25445.194.247.2551,022
19145.194.248.0/2245.194.248.1 to 45.194.251.25445.194.251.2551,022
19245.194.252.0/2245.194.252.1 to 45.194.255.25445.194.255.2551,022
19345.195.0.0/2245.195.0.1 to 45.195.3.25445.195.3.2551,022
19445.195.4.0/2245.195.4.1 to 45.195.7.25445.195.7.2551,022
19545.195.8.0/2245.195.8.1 to 45.195.11.25445.195.11.2551,022
19645.195.12.0/2245.195.12.1 to 45.195.15.25445.195.15.2551,022
19745.195.16.0/2245.195.16.1 to 45.195.19.25445.195.19.2551,022
19845.195.20.0/2245.195.20.1 to 45.195.23.25445.195.23.2551,022
19945.195.24.0/2245.195.24.1 to 45.195.27.25445.195.27.2551,022
20045.195.28.0/2245.195.28.1 to 45.195.31.25445.195.31.2551,022
20145.195.32.0/2245.195.32.1 to 45.195.35.25445.195.35.2551,022
20245.195.36.0/2245.195.36.1 to 45.195.39.25445.195.39.2551,022
20345.195.40.0/2245.195.40.1 to 45.195.43.25445.195.43.2551,022
20445.195.44.0/2245.195.44.1 to 45.195.47.25445.195.47.2551,022
20545.195.48.0/2245.195.48.1 to 45.195.51.25445.195.51.2551,022
20645.195.52.0/2245.195.52.1 to 45.195.55.25445.195.55.2551,022
20745.195.56.0/2245.195.56.1 to 45.195.59.25445.195.59.2551,022
20845.195.60.0/2245.195.60.1 to 45.195.63.25445.195.63.2551,022
20945.195.64.0/2245.195.64.1 to 45.195.67.25445.195.67.2551,022
21045.195.68.0/2245.195.68.1 to 45.195.71.25445.195.71.2551,022
21145.195.72.0/2245.195.72.1 to 45.195.75.25445.195.75.2551,022
21245.195.76.0/2245.195.76.1 to 45.195.79.25445.195.79.2551,022
21345.195.80.0/2245.195.80.1 to 45.195.83.25445.195.83.2551,022
21445.195.84.0/2245.195.84.1 to 45.195.87.25445.195.87.2551,022
21545.195.88.0/2245.195.88.1 to 45.195.91.25445.195.91.2551,022
21645.195.92.0/2245.195.92.1 to 45.195.95.25445.195.95.2551,022
21745.195.96.0/2245.195.96.1 to 45.195.99.25445.195.99.2551,022
21845.195.100.0/2245.195.100.1 to 45.195.103.25445.195.103.2551,022
21945.195.104.0/2245.195.104.1 to 45.195.107.25445.195.107.2551,022
22045.195.108.0/2245.195.108.1 to 45.195.111.25445.195.111.2551,022
22145.195.112.0/2245.195.112.1 to 45.195.115.25445.195.115.2551,022
22245.195.116.0/2245.195.116.1 to 45.195.119.25445.195.119.2551,022
22345.195.120.0/2245.195.120.1 to 45.195.123.25445.195.123.2551,022
22445.195.124.0/2245.195.124.1 to 45.195.127.25445.195.127.2551,022
22545.195.128.0/2245.195.128.1 to 45.195.131.25445.195.131.2551,022
22645.195.132.0/2245.195.132.1 to 45.195.135.25445.195.135.2551,022
22745.195.136.0/2245.195.136.1 to 45.195.139.25445.195.139.2551,022
22845.195.140.0/2245.195.140.1 to 45.195.143.25445.195.143.2551,022
22945.195.144.0/2245.195.144.1 to 45.195.147.25445.195.147.2551,022
23045.195.148.0/2245.195.148.1 to 45.195.151.25445.195.151.2551,022
23145.195.152.0/2245.195.152.1 to 45.195.155.25445.195.155.2551,022
23245.195.156.0/2245.195.156.1 to 45.195.159.25445.195.159.2551,022
23345.195.160.0/2245.195.160.1 to 45.195.163.25445.195.163.2551,022
23445.195.164.0/2245.195.164.1 to 45.195.167.25445.195.167.2551,022
23545.195.168.0/2245.195.168.1 to 45.195.171.25445.195.171.2551,022
23645.195.172.0/2245.195.172.1 to 45.195.175.25445.195.175.2551,022
23745.195.176.0/2245.195.176.1 to 45.195.179.25445.195.179.2551,022
23845.195.180.0/2245.195.180.1 to 45.195.183.25445.195.183.2551,022
23945.195.184.0/2245.195.184.1 to 45.195.187.25445.195.187.2551,022
24045.195.188.0/2245.195.188.1 to 45.195.191.25445.195.191.2551,022
24145.195.192.0/2245.195.192.1 to 45.195.195.25445.195.195.2551,022
24245.195.196.0/2245.195.196.1 to 45.195.199.25445.195.199.2551,022
24345.195.200.0/2245.195.200.1 to 45.195.203.25445.195.203.2551,022
24445.195.204.0/2245.195.204.1 to 45.195.207.25445.195.207.2551,022
24545.195.208.0/2245.195.208.1 to 45.195.211.25445.195.211.2551,022
24645.195.212.0/2245.195.212.1 to 45.195.215.25445.195.215.2551,022
24745.195.216.0/2245.195.216.1 to 45.195.219.25445.195.219.2551,022
24845.195.220.0/2245.195.220.1 to 45.195.223.25445.195.223.2551,022
24945.195.224.0/2245.195.224.1 to 45.195.227.25445.195.227.2551,022
25045.195.228.0/2245.195.228.1 to 45.195.231.25445.195.231.2551,022
25145.195.232.0/2245.195.232.1 to 45.195.235.25445.195.235.2551,022
25245.195.236.0/2245.195.236.1 to 45.195.239.25445.195.239.2551,022
25345.195.240.0/2245.195.240.1 to 45.195.243.25445.195.243.2551,022
25445.195.244.0/2245.195.244.1 to 45.195.247.25445.195.247.2551,022
25545.195.248.0/2245.195.248.1 to 45.195.251.25445.195.251.2551,022
25645.195.252.0/2245.195.252.1 to 45.195.255.25445.195.255.2551,022

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.