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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.

Network38.192.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
38.192.0.0
Broadcast address
38.255.255.255
First usable
38.192.0.1
Last usable
38.255.255.254
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 26C00000 · Integer 650117120 to 654311423
Reverse DNS zones
192.38.in-addr.arpa
193.38.in-addr.arpa
194.38.in-addr.arpa
195.38.in-addr.arpa
196.38.in-addr.arpa
197.38.in-addr.arpa
198.38.in-addr.arpa
199.38.in-addr.arpa
200.38.in-addr.arpa
201.38.in-addr.arpa
202.38.in-addr.arpa
203.38.in-addr.arpa
204.38.in-addr.arpa
205.38.in-addr.arpa
206.38.in-addr.arpa
207.38.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
Address00100110.11000000.00000000.0000000038.192.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00100110.11000000.00000000.0000000038.192.0.0
Broadcast00100110.11111111.11111111.1111111138.255.255.255
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)

38.192.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
138.192.0.0/2238.192.0.1 to 38.192.3.25438.192.3.2551,022
238.192.4.0/2238.192.4.1 to 38.192.7.25438.192.7.2551,022
338.192.8.0/2238.192.8.1 to 38.192.11.25438.192.11.2551,022
438.192.12.0/2238.192.12.1 to 38.192.15.25438.192.15.2551,022
538.192.16.0/2238.192.16.1 to 38.192.19.25438.192.19.2551,022
638.192.20.0/2238.192.20.1 to 38.192.23.25438.192.23.2551,022
738.192.24.0/2238.192.24.1 to 38.192.27.25438.192.27.2551,022
838.192.28.0/2238.192.28.1 to 38.192.31.25438.192.31.2551,022
938.192.32.0/2238.192.32.1 to 38.192.35.25438.192.35.2551,022
1038.192.36.0/2238.192.36.1 to 38.192.39.25438.192.39.2551,022
1138.192.40.0/2238.192.40.1 to 38.192.43.25438.192.43.2551,022
1238.192.44.0/2238.192.44.1 to 38.192.47.25438.192.47.2551,022
1338.192.48.0/2238.192.48.1 to 38.192.51.25438.192.51.2551,022
1438.192.52.0/2238.192.52.1 to 38.192.55.25438.192.55.2551,022
1538.192.56.0/2238.192.56.1 to 38.192.59.25438.192.59.2551,022
1638.192.60.0/2238.192.60.1 to 38.192.63.25438.192.63.2551,022
1738.192.64.0/2238.192.64.1 to 38.192.67.25438.192.67.2551,022
1838.192.68.0/2238.192.68.1 to 38.192.71.25438.192.71.2551,022
1938.192.72.0/2238.192.72.1 to 38.192.75.25438.192.75.2551,022
2038.192.76.0/2238.192.76.1 to 38.192.79.25438.192.79.2551,022
2138.192.80.0/2238.192.80.1 to 38.192.83.25438.192.83.2551,022
2238.192.84.0/2238.192.84.1 to 38.192.87.25438.192.87.2551,022
2338.192.88.0/2238.192.88.1 to 38.192.91.25438.192.91.2551,022
2438.192.92.0/2238.192.92.1 to 38.192.95.25438.192.95.2551,022
2538.192.96.0/2238.192.96.1 to 38.192.99.25438.192.99.2551,022
2638.192.100.0/2238.192.100.1 to 38.192.103.25438.192.103.2551,022
2738.192.104.0/2238.192.104.1 to 38.192.107.25438.192.107.2551,022
2838.192.108.0/2238.192.108.1 to 38.192.111.25438.192.111.2551,022
2938.192.112.0/2238.192.112.1 to 38.192.115.25438.192.115.2551,022
3038.192.116.0/2238.192.116.1 to 38.192.119.25438.192.119.2551,022
3138.192.120.0/2238.192.120.1 to 38.192.123.25438.192.123.2551,022
3238.192.124.0/2238.192.124.1 to 38.192.127.25438.192.127.2551,022
3338.192.128.0/2238.192.128.1 to 38.192.131.25438.192.131.2551,022
3438.192.132.0/2238.192.132.1 to 38.192.135.25438.192.135.2551,022
3538.192.136.0/2238.192.136.1 to 38.192.139.25438.192.139.2551,022
3638.192.140.0/2238.192.140.1 to 38.192.143.25438.192.143.2551,022
3738.192.144.0/2238.192.144.1 to 38.192.147.25438.192.147.2551,022
3838.192.148.0/2238.192.148.1 to 38.192.151.25438.192.151.2551,022
3938.192.152.0/2238.192.152.1 to 38.192.155.25438.192.155.2551,022
4038.192.156.0/2238.192.156.1 to 38.192.159.25438.192.159.2551,022
4138.192.160.0/2238.192.160.1 to 38.192.163.25438.192.163.2551,022
4238.192.164.0/2238.192.164.1 to 38.192.167.25438.192.167.2551,022
4338.192.168.0/2238.192.168.1 to 38.192.171.25438.192.171.2551,022
4438.192.172.0/2238.192.172.1 to 38.192.175.25438.192.175.2551,022
4538.192.176.0/2238.192.176.1 to 38.192.179.25438.192.179.2551,022
4638.192.180.0/2238.192.180.1 to 38.192.183.25438.192.183.2551,022
4738.192.184.0/2238.192.184.1 to 38.192.187.25438.192.187.2551,022
4838.192.188.0/2238.192.188.1 to 38.192.191.25438.192.191.2551,022
4938.192.192.0/2238.192.192.1 to 38.192.195.25438.192.195.2551,022
5038.192.196.0/2238.192.196.1 to 38.192.199.25438.192.199.2551,022
5138.192.200.0/2238.192.200.1 to 38.192.203.25438.192.203.2551,022
5238.192.204.0/2238.192.204.1 to 38.192.207.25438.192.207.2551,022
5338.192.208.0/2238.192.208.1 to 38.192.211.25438.192.211.2551,022
5438.192.212.0/2238.192.212.1 to 38.192.215.25438.192.215.2551,022
5538.192.216.0/2238.192.216.1 to 38.192.219.25438.192.219.2551,022
5638.192.220.0/2238.192.220.1 to 38.192.223.25438.192.223.2551,022
5738.192.224.0/2238.192.224.1 to 38.192.227.25438.192.227.2551,022
5838.192.228.0/2238.192.228.1 to 38.192.231.25438.192.231.2551,022
5938.192.232.0/2238.192.232.1 to 38.192.235.25438.192.235.2551,022
6038.192.236.0/2238.192.236.1 to 38.192.239.25438.192.239.2551,022
6138.192.240.0/2238.192.240.1 to 38.192.243.25438.192.243.2551,022
6238.192.244.0/2238.192.244.1 to 38.192.247.25438.192.247.2551,022
6338.192.248.0/2238.192.248.1 to 38.192.251.25438.192.251.2551,022
6438.192.252.0/2238.192.252.1 to 38.192.255.25438.192.255.2551,022
6538.193.0.0/2238.193.0.1 to 38.193.3.25438.193.3.2551,022
6638.193.4.0/2238.193.4.1 to 38.193.7.25438.193.7.2551,022
6738.193.8.0/2238.193.8.1 to 38.193.11.25438.193.11.2551,022
6838.193.12.0/2238.193.12.1 to 38.193.15.25438.193.15.2551,022
6938.193.16.0/2238.193.16.1 to 38.193.19.25438.193.19.2551,022
7038.193.20.0/2238.193.20.1 to 38.193.23.25438.193.23.2551,022
7138.193.24.0/2238.193.24.1 to 38.193.27.25438.193.27.2551,022
7238.193.28.0/2238.193.28.1 to 38.193.31.25438.193.31.2551,022
7338.193.32.0/2238.193.32.1 to 38.193.35.25438.193.35.2551,022
7438.193.36.0/2238.193.36.1 to 38.193.39.25438.193.39.2551,022
7538.193.40.0/2238.193.40.1 to 38.193.43.25438.193.43.2551,022
7638.193.44.0/2238.193.44.1 to 38.193.47.25438.193.47.2551,022
7738.193.48.0/2238.193.48.1 to 38.193.51.25438.193.51.2551,022
7838.193.52.0/2238.193.52.1 to 38.193.55.25438.193.55.2551,022
7938.193.56.0/2238.193.56.1 to 38.193.59.25438.193.59.2551,022
8038.193.60.0/2238.193.60.1 to 38.193.63.25438.193.63.2551,022
8138.193.64.0/2238.193.64.1 to 38.193.67.25438.193.67.2551,022
8238.193.68.0/2238.193.68.1 to 38.193.71.25438.193.71.2551,022
8338.193.72.0/2238.193.72.1 to 38.193.75.25438.193.75.2551,022
8438.193.76.0/2238.193.76.1 to 38.193.79.25438.193.79.2551,022
8538.193.80.0/2238.193.80.1 to 38.193.83.25438.193.83.2551,022
8638.193.84.0/2238.193.84.1 to 38.193.87.25438.193.87.2551,022
8738.193.88.0/2238.193.88.1 to 38.193.91.25438.193.91.2551,022
8838.193.92.0/2238.193.92.1 to 38.193.95.25438.193.95.2551,022
8938.193.96.0/2238.193.96.1 to 38.193.99.25438.193.99.2551,022
9038.193.100.0/2238.193.100.1 to 38.193.103.25438.193.103.2551,022
9138.193.104.0/2238.193.104.1 to 38.193.107.25438.193.107.2551,022
9238.193.108.0/2238.193.108.1 to 38.193.111.25438.193.111.2551,022
9338.193.112.0/2238.193.112.1 to 38.193.115.25438.193.115.2551,022
9438.193.116.0/2238.193.116.1 to 38.193.119.25438.193.119.2551,022
9538.193.120.0/2238.193.120.1 to 38.193.123.25438.193.123.2551,022
9638.193.124.0/2238.193.124.1 to 38.193.127.25438.193.127.2551,022
9738.193.128.0/2238.193.128.1 to 38.193.131.25438.193.131.2551,022
9838.193.132.0/2238.193.132.1 to 38.193.135.25438.193.135.2551,022
9938.193.136.0/2238.193.136.1 to 38.193.139.25438.193.139.2551,022
10038.193.140.0/2238.193.140.1 to 38.193.143.25438.193.143.2551,022
10138.193.144.0/2238.193.144.1 to 38.193.147.25438.193.147.2551,022
10238.193.148.0/2238.193.148.1 to 38.193.151.25438.193.151.2551,022
10338.193.152.0/2238.193.152.1 to 38.193.155.25438.193.155.2551,022
10438.193.156.0/2238.193.156.1 to 38.193.159.25438.193.159.2551,022
10538.193.160.0/2238.193.160.1 to 38.193.163.25438.193.163.2551,022
10638.193.164.0/2238.193.164.1 to 38.193.167.25438.193.167.2551,022
10738.193.168.0/2238.193.168.1 to 38.193.171.25438.193.171.2551,022
10838.193.172.0/2238.193.172.1 to 38.193.175.25438.193.175.2551,022
10938.193.176.0/2238.193.176.1 to 38.193.179.25438.193.179.2551,022
11038.193.180.0/2238.193.180.1 to 38.193.183.25438.193.183.2551,022
11138.193.184.0/2238.193.184.1 to 38.193.187.25438.193.187.2551,022
11238.193.188.0/2238.193.188.1 to 38.193.191.25438.193.191.2551,022
11338.193.192.0/2238.193.192.1 to 38.193.195.25438.193.195.2551,022
11438.193.196.0/2238.193.196.1 to 38.193.199.25438.193.199.2551,022
11538.193.200.0/2238.193.200.1 to 38.193.203.25438.193.203.2551,022
11638.193.204.0/2238.193.204.1 to 38.193.207.25438.193.207.2551,022
11738.193.208.0/2238.193.208.1 to 38.193.211.25438.193.211.2551,022
11838.193.212.0/2238.193.212.1 to 38.193.215.25438.193.215.2551,022
11938.193.216.0/2238.193.216.1 to 38.193.219.25438.193.219.2551,022
12038.193.220.0/2238.193.220.1 to 38.193.223.25438.193.223.2551,022
12138.193.224.0/2238.193.224.1 to 38.193.227.25438.193.227.2551,022
12238.193.228.0/2238.193.228.1 to 38.193.231.25438.193.231.2551,022
12338.193.232.0/2238.193.232.1 to 38.193.235.25438.193.235.2551,022
12438.193.236.0/2238.193.236.1 to 38.193.239.25438.193.239.2551,022
12538.193.240.0/2238.193.240.1 to 38.193.243.25438.193.243.2551,022
12638.193.244.0/2238.193.244.1 to 38.193.247.25438.193.247.2551,022
12738.193.248.0/2238.193.248.1 to 38.193.251.25438.193.251.2551,022
12838.193.252.0/2238.193.252.1 to 38.193.255.25438.193.255.2551,022
12938.194.0.0/2238.194.0.1 to 38.194.3.25438.194.3.2551,022
13038.194.4.0/2238.194.4.1 to 38.194.7.25438.194.7.2551,022
13138.194.8.0/2238.194.8.1 to 38.194.11.25438.194.11.2551,022
13238.194.12.0/2238.194.12.1 to 38.194.15.25438.194.15.2551,022
13338.194.16.0/2238.194.16.1 to 38.194.19.25438.194.19.2551,022
13438.194.20.0/2238.194.20.1 to 38.194.23.25438.194.23.2551,022
13538.194.24.0/2238.194.24.1 to 38.194.27.25438.194.27.2551,022
13638.194.28.0/2238.194.28.1 to 38.194.31.25438.194.31.2551,022
13738.194.32.0/2238.194.32.1 to 38.194.35.25438.194.35.2551,022
13838.194.36.0/2238.194.36.1 to 38.194.39.25438.194.39.2551,022
13938.194.40.0/2238.194.40.1 to 38.194.43.25438.194.43.2551,022
14038.194.44.0/2238.194.44.1 to 38.194.47.25438.194.47.2551,022
14138.194.48.0/2238.194.48.1 to 38.194.51.25438.194.51.2551,022
14238.194.52.0/2238.194.52.1 to 38.194.55.25438.194.55.2551,022
14338.194.56.0/2238.194.56.1 to 38.194.59.25438.194.59.2551,022
14438.194.60.0/2238.194.60.1 to 38.194.63.25438.194.63.2551,022
14538.194.64.0/2238.194.64.1 to 38.194.67.25438.194.67.2551,022
14638.194.68.0/2238.194.68.1 to 38.194.71.25438.194.71.2551,022
14738.194.72.0/2238.194.72.1 to 38.194.75.25438.194.75.2551,022
14838.194.76.0/2238.194.76.1 to 38.194.79.25438.194.79.2551,022
14938.194.80.0/2238.194.80.1 to 38.194.83.25438.194.83.2551,022
15038.194.84.0/2238.194.84.1 to 38.194.87.25438.194.87.2551,022
15138.194.88.0/2238.194.88.1 to 38.194.91.25438.194.91.2551,022
15238.194.92.0/2238.194.92.1 to 38.194.95.25438.194.95.2551,022
15338.194.96.0/2238.194.96.1 to 38.194.99.25438.194.99.2551,022
15438.194.100.0/2238.194.100.1 to 38.194.103.25438.194.103.2551,022
15538.194.104.0/2238.194.104.1 to 38.194.107.25438.194.107.2551,022
15638.194.108.0/2238.194.108.1 to 38.194.111.25438.194.111.2551,022
15738.194.112.0/2238.194.112.1 to 38.194.115.25438.194.115.2551,022
15838.194.116.0/2238.194.116.1 to 38.194.119.25438.194.119.2551,022
15938.194.120.0/2238.194.120.1 to 38.194.123.25438.194.123.2551,022
16038.194.124.0/2238.194.124.1 to 38.194.127.25438.194.127.2551,022
16138.194.128.0/2238.194.128.1 to 38.194.131.25438.194.131.2551,022
16238.194.132.0/2238.194.132.1 to 38.194.135.25438.194.135.2551,022
16338.194.136.0/2238.194.136.1 to 38.194.139.25438.194.139.2551,022
16438.194.140.0/2238.194.140.1 to 38.194.143.25438.194.143.2551,022
16538.194.144.0/2238.194.144.1 to 38.194.147.25438.194.147.2551,022
16638.194.148.0/2238.194.148.1 to 38.194.151.25438.194.151.2551,022
16738.194.152.0/2238.194.152.1 to 38.194.155.25438.194.155.2551,022
16838.194.156.0/2238.194.156.1 to 38.194.159.25438.194.159.2551,022
16938.194.160.0/2238.194.160.1 to 38.194.163.25438.194.163.2551,022
17038.194.164.0/2238.194.164.1 to 38.194.167.25438.194.167.2551,022
17138.194.168.0/2238.194.168.1 to 38.194.171.25438.194.171.2551,022
17238.194.172.0/2238.194.172.1 to 38.194.175.25438.194.175.2551,022
17338.194.176.0/2238.194.176.1 to 38.194.179.25438.194.179.2551,022
17438.194.180.0/2238.194.180.1 to 38.194.183.25438.194.183.2551,022
17538.194.184.0/2238.194.184.1 to 38.194.187.25438.194.187.2551,022
17638.194.188.0/2238.194.188.1 to 38.194.191.25438.194.191.2551,022
17738.194.192.0/2238.194.192.1 to 38.194.195.25438.194.195.2551,022
17838.194.196.0/2238.194.196.1 to 38.194.199.25438.194.199.2551,022
17938.194.200.0/2238.194.200.1 to 38.194.203.25438.194.203.2551,022
18038.194.204.0/2238.194.204.1 to 38.194.207.25438.194.207.2551,022
18138.194.208.0/2238.194.208.1 to 38.194.211.25438.194.211.2551,022
18238.194.212.0/2238.194.212.1 to 38.194.215.25438.194.215.2551,022
18338.194.216.0/2238.194.216.1 to 38.194.219.25438.194.219.2551,022
18438.194.220.0/2238.194.220.1 to 38.194.223.25438.194.223.2551,022
18538.194.224.0/2238.194.224.1 to 38.194.227.25438.194.227.2551,022
18638.194.228.0/2238.194.228.1 to 38.194.231.25438.194.231.2551,022
18738.194.232.0/2238.194.232.1 to 38.194.235.25438.194.235.2551,022
18838.194.236.0/2238.194.236.1 to 38.194.239.25438.194.239.2551,022
18938.194.240.0/2238.194.240.1 to 38.194.243.25438.194.243.2551,022
19038.194.244.0/2238.194.244.1 to 38.194.247.25438.194.247.2551,022
19138.194.248.0/2238.194.248.1 to 38.194.251.25438.194.251.2551,022
19238.194.252.0/2238.194.252.1 to 38.194.255.25438.194.255.2551,022
19338.195.0.0/2238.195.0.1 to 38.195.3.25438.195.3.2551,022
19438.195.4.0/2238.195.4.1 to 38.195.7.25438.195.7.2551,022
19538.195.8.0/2238.195.8.1 to 38.195.11.25438.195.11.2551,022
19638.195.12.0/2238.195.12.1 to 38.195.15.25438.195.15.2551,022
19738.195.16.0/2238.195.16.1 to 38.195.19.25438.195.19.2551,022
19838.195.20.0/2238.195.20.1 to 38.195.23.25438.195.23.2551,022
19938.195.24.0/2238.195.24.1 to 38.195.27.25438.195.27.2551,022
20038.195.28.0/2238.195.28.1 to 38.195.31.25438.195.31.2551,022
20138.195.32.0/2238.195.32.1 to 38.195.35.25438.195.35.2551,022
20238.195.36.0/2238.195.36.1 to 38.195.39.25438.195.39.2551,022
20338.195.40.0/2238.195.40.1 to 38.195.43.25438.195.43.2551,022
20438.195.44.0/2238.195.44.1 to 38.195.47.25438.195.47.2551,022
20538.195.48.0/2238.195.48.1 to 38.195.51.25438.195.51.2551,022
20638.195.52.0/2238.195.52.1 to 38.195.55.25438.195.55.2551,022
20738.195.56.0/2238.195.56.1 to 38.195.59.25438.195.59.2551,022
20838.195.60.0/2238.195.60.1 to 38.195.63.25438.195.63.2551,022
20938.195.64.0/2238.195.64.1 to 38.195.67.25438.195.67.2551,022
21038.195.68.0/2238.195.68.1 to 38.195.71.25438.195.71.2551,022
21138.195.72.0/2238.195.72.1 to 38.195.75.25438.195.75.2551,022
21238.195.76.0/2238.195.76.1 to 38.195.79.25438.195.79.2551,022
21338.195.80.0/2238.195.80.1 to 38.195.83.25438.195.83.2551,022
21438.195.84.0/2238.195.84.1 to 38.195.87.25438.195.87.2551,022
21538.195.88.0/2238.195.88.1 to 38.195.91.25438.195.91.2551,022
21638.195.92.0/2238.195.92.1 to 38.195.95.25438.195.95.2551,022
21738.195.96.0/2238.195.96.1 to 38.195.99.25438.195.99.2551,022
21838.195.100.0/2238.195.100.1 to 38.195.103.25438.195.103.2551,022
21938.195.104.0/2238.195.104.1 to 38.195.107.25438.195.107.2551,022
22038.195.108.0/2238.195.108.1 to 38.195.111.25438.195.111.2551,022
22138.195.112.0/2238.195.112.1 to 38.195.115.25438.195.115.2551,022
22238.195.116.0/2238.195.116.1 to 38.195.119.25438.195.119.2551,022
22338.195.120.0/2238.195.120.1 to 38.195.123.25438.195.123.2551,022
22438.195.124.0/2238.195.124.1 to 38.195.127.25438.195.127.2551,022
22538.195.128.0/2238.195.128.1 to 38.195.131.25438.195.131.2551,022
22638.195.132.0/2238.195.132.1 to 38.195.135.25438.195.135.2551,022
22738.195.136.0/2238.195.136.1 to 38.195.139.25438.195.139.2551,022
22838.195.140.0/2238.195.140.1 to 38.195.143.25438.195.143.2551,022
22938.195.144.0/2238.195.144.1 to 38.195.147.25438.195.147.2551,022
23038.195.148.0/2238.195.148.1 to 38.195.151.25438.195.151.2551,022
23138.195.152.0/2238.195.152.1 to 38.195.155.25438.195.155.2551,022
23238.195.156.0/2238.195.156.1 to 38.195.159.25438.195.159.2551,022
23338.195.160.0/2238.195.160.1 to 38.195.163.25438.195.163.2551,022
23438.195.164.0/2238.195.164.1 to 38.195.167.25438.195.167.2551,022
23538.195.168.0/2238.195.168.1 to 38.195.171.25438.195.171.2551,022
23638.195.172.0/2238.195.172.1 to 38.195.175.25438.195.175.2551,022
23738.195.176.0/2238.195.176.1 to 38.195.179.25438.195.179.2551,022
23838.195.180.0/2238.195.180.1 to 38.195.183.25438.195.183.2551,022
23938.195.184.0/2238.195.184.1 to 38.195.187.25438.195.187.2551,022
24038.195.188.0/2238.195.188.1 to 38.195.191.25438.195.191.2551,022
24138.195.192.0/2238.195.192.1 to 38.195.195.25438.195.195.2551,022
24238.195.196.0/2238.195.196.1 to 38.195.199.25438.195.199.2551,022
24338.195.200.0/2238.195.200.1 to 38.195.203.25438.195.203.2551,022
24438.195.204.0/2238.195.204.1 to 38.195.207.25438.195.207.2551,022
24538.195.208.0/2238.195.208.1 to 38.195.211.25438.195.211.2551,022
24638.195.212.0/2238.195.212.1 to 38.195.215.25438.195.215.2551,022
24738.195.216.0/2238.195.216.1 to 38.195.219.25438.195.219.2551,022
24838.195.220.0/2238.195.220.1 to 38.195.223.25438.195.223.2551,022
24938.195.224.0/2238.195.224.1 to 38.195.227.25438.195.227.2551,022
25038.195.228.0/2238.195.228.1 to 38.195.231.25438.195.231.2551,022
25138.195.232.0/2238.195.232.1 to 38.195.235.25438.195.235.2551,022
25238.195.236.0/2238.195.236.1 to 38.195.239.25438.195.239.2551,022
25338.195.240.0/2238.195.240.1 to 38.195.243.25438.195.243.2551,022
25438.195.244.0/2238.195.244.1 to 38.195.247.25438.195.247.2551,022
25538.195.248.0/2238.195.248.1 to 38.195.251.25438.195.251.2551,022
25638.195.252.0/2238.195.252.1 to 38.195.255.25438.195.255.2551,022

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.