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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.

Network90.64.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
90.64.0.0
Broadcast address
90.71.255.255
First usable
90.64.0.1
Last usable
90.71.255.254
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 5A400000 · Integer 1514143744 to 1514668031
Reverse DNS zones
64.90.in-addr.arpa
65.90.in-addr.arpa
66.90.in-addr.arpa
67.90.in-addr.arpa
68.90.in-addr.arpa
69.90.in-addr.arpa
70.90.in-addr.arpa
71.90.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
Address01011010.01000000.00000000.0000000090.64.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01011010.01000000.00000000.0000000090.64.0.0
Broadcast01011010.01000111.11111111.1111111190.71.255.255
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)

90.64.0.0/13 makes 512 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
190.64.0.0/2290.64.0.1 to 90.64.3.25490.64.3.2551,022
290.64.4.0/2290.64.4.1 to 90.64.7.25490.64.7.2551,022
390.64.8.0/2290.64.8.1 to 90.64.11.25490.64.11.2551,022
490.64.12.0/2290.64.12.1 to 90.64.15.25490.64.15.2551,022
590.64.16.0/2290.64.16.1 to 90.64.19.25490.64.19.2551,022
690.64.20.0/2290.64.20.1 to 90.64.23.25490.64.23.2551,022
790.64.24.0/2290.64.24.1 to 90.64.27.25490.64.27.2551,022
890.64.28.0/2290.64.28.1 to 90.64.31.25490.64.31.2551,022
990.64.32.0/2290.64.32.1 to 90.64.35.25490.64.35.2551,022
1090.64.36.0/2290.64.36.1 to 90.64.39.25490.64.39.2551,022
1190.64.40.0/2290.64.40.1 to 90.64.43.25490.64.43.2551,022
1290.64.44.0/2290.64.44.1 to 90.64.47.25490.64.47.2551,022
1390.64.48.0/2290.64.48.1 to 90.64.51.25490.64.51.2551,022
1490.64.52.0/2290.64.52.1 to 90.64.55.25490.64.55.2551,022
1590.64.56.0/2290.64.56.1 to 90.64.59.25490.64.59.2551,022
1690.64.60.0/2290.64.60.1 to 90.64.63.25490.64.63.2551,022
1790.64.64.0/2290.64.64.1 to 90.64.67.25490.64.67.2551,022
1890.64.68.0/2290.64.68.1 to 90.64.71.25490.64.71.2551,022
1990.64.72.0/2290.64.72.1 to 90.64.75.25490.64.75.2551,022
2090.64.76.0/2290.64.76.1 to 90.64.79.25490.64.79.2551,022
2190.64.80.0/2290.64.80.1 to 90.64.83.25490.64.83.2551,022
2290.64.84.0/2290.64.84.1 to 90.64.87.25490.64.87.2551,022
2390.64.88.0/2290.64.88.1 to 90.64.91.25490.64.91.2551,022
2490.64.92.0/2290.64.92.1 to 90.64.95.25490.64.95.2551,022
2590.64.96.0/2290.64.96.1 to 90.64.99.25490.64.99.2551,022
2690.64.100.0/2290.64.100.1 to 90.64.103.25490.64.103.2551,022
2790.64.104.0/2290.64.104.1 to 90.64.107.25490.64.107.2551,022
2890.64.108.0/2290.64.108.1 to 90.64.111.25490.64.111.2551,022
2990.64.112.0/2290.64.112.1 to 90.64.115.25490.64.115.2551,022
3090.64.116.0/2290.64.116.1 to 90.64.119.25490.64.119.2551,022
3190.64.120.0/2290.64.120.1 to 90.64.123.25490.64.123.2551,022
3290.64.124.0/2290.64.124.1 to 90.64.127.25490.64.127.2551,022
3390.64.128.0/2290.64.128.1 to 90.64.131.25490.64.131.2551,022
3490.64.132.0/2290.64.132.1 to 90.64.135.25490.64.135.2551,022
3590.64.136.0/2290.64.136.1 to 90.64.139.25490.64.139.2551,022
3690.64.140.0/2290.64.140.1 to 90.64.143.25490.64.143.2551,022
3790.64.144.0/2290.64.144.1 to 90.64.147.25490.64.147.2551,022
3890.64.148.0/2290.64.148.1 to 90.64.151.25490.64.151.2551,022
3990.64.152.0/2290.64.152.1 to 90.64.155.25490.64.155.2551,022
4090.64.156.0/2290.64.156.1 to 90.64.159.25490.64.159.2551,022
4190.64.160.0/2290.64.160.1 to 90.64.163.25490.64.163.2551,022
4290.64.164.0/2290.64.164.1 to 90.64.167.25490.64.167.2551,022
4390.64.168.0/2290.64.168.1 to 90.64.171.25490.64.171.2551,022
4490.64.172.0/2290.64.172.1 to 90.64.175.25490.64.175.2551,022
4590.64.176.0/2290.64.176.1 to 90.64.179.25490.64.179.2551,022
4690.64.180.0/2290.64.180.1 to 90.64.183.25490.64.183.2551,022
4790.64.184.0/2290.64.184.1 to 90.64.187.25490.64.187.2551,022
4890.64.188.0/2290.64.188.1 to 90.64.191.25490.64.191.2551,022
4990.64.192.0/2290.64.192.1 to 90.64.195.25490.64.195.2551,022
5090.64.196.0/2290.64.196.1 to 90.64.199.25490.64.199.2551,022
5190.64.200.0/2290.64.200.1 to 90.64.203.25490.64.203.2551,022
5290.64.204.0/2290.64.204.1 to 90.64.207.25490.64.207.2551,022
5390.64.208.0/2290.64.208.1 to 90.64.211.25490.64.211.2551,022
5490.64.212.0/2290.64.212.1 to 90.64.215.25490.64.215.2551,022
5590.64.216.0/2290.64.216.1 to 90.64.219.25490.64.219.2551,022
5690.64.220.0/2290.64.220.1 to 90.64.223.25490.64.223.2551,022
5790.64.224.0/2290.64.224.1 to 90.64.227.25490.64.227.2551,022
5890.64.228.0/2290.64.228.1 to 90.64.231.25490.64.231.2551,022
5990.64.232.0/2290.64.232.1 to 90.64.235.25490.64.235.2551,022
6090.64.236.0/2290.64.236.1 to 90.64.239.25490.64.239.2551,022
6190.64.240.0/2290.64.240.1 to 90.64.243.25490.64.243.2551,022
6290.64.244.0/2290.64.244.1 to 90.64.247.25490.64.247.2551,022
6390.64.248.0/2290.64.248.1 to 90.64.251.25490.64.251.2551,022
6490.64.252.0/2290.64.252.1 to 90.64.255.25490.64.255.2551,022
6590.65.0.0/2290.65.0.1 to 90.65.3.25490.65.3.2551,022
6690.65.4.0/2290.65.4.1 to 90.65.7.25490.65.7.2551,022
6790.65.8.0/2290.65.8.1 to 90.65.11.25490.65.11.2551,022
6890.65.12.0/2290.65.12.1 to 90.65.15.25490.65.15.2551,022
6990.65.16.0/2290.65.16.1 to 90.65.19.25490.65.19.2551,022
7090.65.20.0/2290.65.20.1 to 90.65.23.25490.65.23.2551,022
7190.65.24.0/2290.65.24.1 to 90.65.27.25490.65.27.2551,022
7290.65.28.0/2290.65.28.1 to 90.65.31.25490.65.31.2551,022
7390.65.32.0/2290.65.32.1 to 90.65.35.25490.65.35.2551,022
7490.65.36.0/2290.65.36.1 to 90.65.39.25490.65.39.2551,022
7590.65.40.0/2290.65.40.1 to 90.65.43.25490.65.43.2551,022
7690.65.44.0/2290.65.44.1 to 90.65.47.25490.65.47.2551,022
7790.65.48.0/2290.65.48.1 to 90.65.51.25490.65.51.2551,022
7890.65.52.0/2290.65.52.1 to 90.65.55.25490.65.55.2551,022
7990.65.56.0/2290.65.56.1 to 90.65.59.25490.65.59.2551,022
8090.65.60.0/2290.65.60.1 to 90.65.63.25490.65.63.2551,022
8190.65.64.0/2290.65.64.1 to 90.65.67.25490.65.67.2551,022
8290.65.68.0/2290.65.68.1 to 90.65.71.25490.65.71.2551,022
8390.65.72.0/2290.65.72.1 to 90.65.75.25490.65.75.2551,022
8490.65.76.0/2290.65.76.1 to 90.65.79.25490.65.79.2551,022
8590.65.80.0/2290.65.80.1 to 90.65.83.25490.65.83.2551,022
8690.65.84.0/2290.65.84.1 to 90.65.87.25490.65.87.2551,022
8790.65.88.0/2290.65.88.1 to 90.65.91.25490.65.91.2551,022
8890.65.92.0/2290.65.92.1 to 90.65.95.25490.65.95.2551,022
8990.65.96.0/2290.65.96.1 to 90.65.99.25490.65.99.2551,022
9090.65.100.0/2290.65.100.1 to 90.65.103.25490.65.103.2551,022
9190.65.104.0/2290.65.104.1 to 90.65.107.25490.65.107.2551,022
9290.65.108.0/2290.65.108.1 to 90.65.111.25490.65.111.2551,022
9390.65.112.0/2290.65.112.1 to 90.65.115.25490.65.115.2551,022
9490.65.116.0/2290.65.116.1 to 90.65.119.25490.65.119.2551,022
9590.65.120.0/2290.65.120.1 to 90.65.123.25490.65.123.2551,022
9690.65.124.0/2290.65.124.1 to 90.65.127.25490.65.127.2551,022
9790.65.128.0/2290.65.128.1 to 90.65.131.25490.65.131.2551,022
9890.65.132.0/2290.65.132.1 to 90.65.135.25490.65.135.2551,022
9990.65.136.0/2290.65.136.1 to 90.65.139.25490.65.139.2551,022
10090.65.140.0/2290.65.140.1 to 90.65.143.25490.65.143.2551,022
10190.65.144.0/2290.65.144.1 to 90.65.147.25490.65.147.2551,022
10290.65.148.0/2290.65.148.1 to 90.65.151.25490.65.151.2551,022
10390.65.152.0/2290.65.152.1 to 90.65.155.25490.65.155.2551,022
10490.65.156.0/2290.65.156.1 to 90.65.159.25490.65.159.2551,022
10590.65.160.0/2290.65.160.1 to 90.65.163.25490.65.163.2551,022
10690.65.164.0/2290.65.164.1 to 90.65.167.25490.65.167.2551,022
10790.65.168.0/2290.65.168.1 to 90.65.171.25490.65.171.2551,022
10890.65.172.0/2290.65.172.1 to 90.65.175.25490.65.175.2551,022
10990.65.176.0/2290.65.176.1 to 90.65.179.25490.65.179.2551,022
11090.65.180.0/2290.65.180.1 to 90.65.183.25490.65.183.2551,022
11190.65.184.0/2290.65.184.1 to 90.65.187.25490.65.187.2551,022
11290.65.188.0/2290.65.188.1 to 90.65.191.25490.65.191.2551,022
11390.65.192.0/2290.65.192.1 to 90.65.195.25490.65.195.2551,022
11490.65.196.0/2290.65.196.1 to 90.65.199.25490.65.199.2551,022
11590.65.200.0/2290.65.200.1 to 90.65.203.25490.65.203.2551,022
11690.65.204.0/2290.65.204.1 to 90.65.207.25490.65.207.2551,022
11790.65.208.0/2290.65.208.1 to 90.65.211.25490.65.211.2551,022
11890.65.212.0/2290.65.212.1 to 90.65.215.25490.65.215.2551,022
11990.65.216.0/2290.65.216.1 to 90.65.219.25490.65.219.2551,022
12090.65.220.0/2290.65.220.1 to 90.65.223.25490.65.223.2551,022
12190.65.224.0/2290.65.224.1 to 90.65.227.25490.65.227.2551,022
12290.65.228.0/2290.65.228.1 to 90.65.231.25490.65.231.2551,022
12390.65.232.0/2290.65.232.1 to 90.65.235.25490.65.235.2551,022
12490.65.236.0/2290.65.236.1 to 90.65.239.25490.65.239.2551,022
12590.65.240.0/2290.65.240.1 to 90.65.243.25490.65.243.2551,022
12690.65.244.0/2290.65.244.1 to 90.65.247.25490.65.247.2551,022
12790.65.248.0/2290.65.248.1 to 90.65.251.25490.65.251.2551,022
12890.65.252.0/2290.65.252.1 to 90.65.255.25490.65.255.2551,022
12990.66.0.0/2290.66.0.1 to 90.66.3.25490.66.3.2551,022
13090.66.4.0/2290.66.4.1 to 90.66.7.25490.66.7.2551,022
13190.66.8.0/2290.66.8.1 to 90.66.11.25490.66.11.2551,022
13290.66.12.0/2290.66.12.1 to 90.66.15.25490.66.15.2551,022
13390.66.16.0/2290.66.16.1 to 90.66.19.25490.66.19.2551,022
13490.66.20.0/2290.66.20.1 to 90.66.23.25490.66.23.2551,022
13590.66.24.0/2290.66.24.1 to 90.66.27.25490.66.27.2551,022
13690.66.28.0/2290.66.28.1 to 90.66.31.25490.66.31.2551,022
13790.66.32.0/2290.66.32.1 to 90.66.35.25490.66.35.2551,022
13890.66.36.0/2290.66.36.1 to 90.66.39.25490.66.39.2551,022
13990.66.40.0/2290.66.40.1 to 90.66.43.25490.66.43.2551,022
14090.66.44.0/2290.66.44.1 to 90.66.47.25490.66.47.2551,022
14190.66.48.0/2290.66.48.1 to 90.66.51.25490.66.51.2551,022
14290.66.52.0/2290.66.52.1 to 90.66.55.25490.66.55.2551,022
14390.66.56.0/2290.66.56.1 to 90.66.59.25490.66.59.2551,022
14490.66.60.0/2290.66.60.1 to 90.66.63.25490.66.63.2551,022
14590.66.64.0/2290.66.64.1 to 90.66.67.25490.66.67.2551,022
14690.66.68.0/2290.66.68.1 to 90.66.71.25490.66.71.2551,022
14790.66.72.0/2290.66.72.1 to 90.66.75.25490.66.75.2551,022
14890.66.76.0/2290.66.76.1 to 90.66.79.25490.66.79.2551,022
14990.66.80.0/2290.66.80.1 to 90.66.83.25490.66.83.2551,022
15090.66.84.0/2290.66.84.1 to 90.66.87.25490.66.87.2551,022
15190.66.88.0/2290.66.88.1 to 90.66.91.25490.66.91.2551,022
15290.66.92.0/2290.66.92.1 to 90.66.95.25490.66.95.2551,022
15390.66.96.0/2290.66.96.1 to 90.66.99.25490.66.99.2551,022
15490.66.100.0/2290.66.100.1 to 90.66.103.25490.66.103.2551,022
15590.66.104.0/2290.66.104.1 to 90.66.107.25490.66.107.2551,022
15690.66.108.0/2290.66.108.1 to 90.66.111.25490.66.111.2551,022
15790.66.112.0/2290.66.112.1 to 90.66.115.25490.66.115.2551,022
15890.66.116.0/2290.66.116.1 to 90.66.119.25490.66.119.2551,022
15990.66.120.0/2290.66.120.1 to 90.66.123.25490.66.123.2551,022
16090.66.124.0/2290.66.124.1 to 90.66.127.25490.66.127.2551,022
16190.66.128.0/2290.66.128.1 to 90.66.131.25490.66.131.2551,022
16290.66.132.0/2290.66.132.1 to 90.66.135.25490.66.135.2551,022
16390.66.136.0/2290.66.136.1 to 90.66.139.25490.66.139.2551,022
16490.66.140.0/2290.66.140.1 to 90.66.143.25490.66.143.2551,022
16590.66.144.0/2290.66.144.1 to 90.66.147.25490.66.147.2551,022
16690.66.148.0/2290.66.148.1 to 90.66.151.25490.66.151.2551,022
16790.66.152.0/2290.66.152.1 to 90.66.155.25490.66.155.2551,022
16890.66.156.0/2290.66.156.1 to 90.66.159.25490.66.159.2551,022
16990.66.160.0/2290.66.160.1 to 90.66.163.25490.66.163.2551,022
17090.66.164.0/2290.66.164.1 to 90.66.167.25490.66.167.2551,022
17190.66.168.0/2290.66.168.1 to 90.66.171.25490.66.171.2551,022
17290.66.172.0/2290.66.172.1 to 90.66.175.25490.66.175.2551,022
17390.66.176.0/2290.66.176.1 to 90.66.179.25490.66.179.2551,022
17490.66.180.0/2290.66.180.1 to 90.66.183.25490.66.183.2551,022
17590.66.184.0/2290.66.184.1 to 90.66.187.25490.66.187.2551,022
17690.66.188.0/2290.66.188.1 to 90.66.191.25490.66.191.2551,022
17790.66.192.0/2290.66.192.1 to 90.66.195.25490.66.195.2551,022
17890.66.196.0/2290.66.196.1 to 90.66.199.25490.66.199.2551,022
17990.66.200.0/2290.66.200.1 to 90.66.203.25490.66.203.2551,022
18090.66.204.0/2290.66.204.1 to 90.66.207.25490.66.207.2551,022
18190.66.208.0/2290.66.208.1 to 90.66.211.25490.66.211.2551,022
18290.66.212.0/2290.66.212.1 to 90.66.215.25490.66.215.2551,022
18390.66.216.0/2290.66.216.1 to 90.66.219.25490.66.219.2551,022
18490.66.220.0/2290.66.220.1 to 90.66.223.25490.66.223.2551,022
18590.66.224.0/2290.66.224.1 to 90.66.227.25490.66.227.2551,022
18690.66.228.0/2290.66.228.1 to 90.66.231.25490.66.231.2551,022
18790.66.232.0/2290.66.232.1 to 90.66.235.25490.66.235.2551,022
18890.66.236.0/2290.66.236.1 to 90.66.239.25490.66.239.2551,022
18990.66.240.0/2290.66.240.1 to 90.66.243.25490.66.243.2551,022
19090.66.244.0/2290.66.244.1 to 90.66.247.25490.66.247.2551,022
19190.66.248.0/2290.66.248.1 to 90.66.251.25490.66.251.2551,022
19290.66.252.0/2290.66.252.1 to 90.66.255.25490.66.255.2551,022
19390.67.0.0/2290.67.0.1 to 90.67.3.25490.67.3.2551,022
19490.67.4.0/2290.67.4.1 to 90.67.7.25490.67.7.2551,022
19590.67.8.0/2290.67.8.1 to 90.67.11.25490.67.11.2551,022
19690.67.12.0/2290.67.12.1 to 90.67.15.25490.67.15.2551,022
19790.67.16.0/2290.67.16.1 to 90.67.19.25490.67.19.2551,022
19890.67.20.0/2290.67.20.1 to 90.67.23.25490.67.23.2551,022
19990.67.24.0/2290.67.24.1 to 90.67.27.25490.67.27.2551,022
20090.67.28.0/2290.67.28.1 to 90.67.31.25490.67.31.2551,022
20190.67.32.0/2290.67.32.1 to 90.67.35.25490.67.35.2551,022
20290.67.36.0/2290.67.36.1 to 90.67.39.25490.67.39.2551,022
20390.67.40.0/2290.67.40.1 to 90.67.43.25490.67.43.2551,022
20490.67.44.0/2290.67.44.1 to 90.67.47.25490.67.47.2551,022
20590.67.48.0/2290.67.48.1 to 90.67.51.25490.67.51.2551,022
20690.67.52.0/2290.67.52.1 to 90.67.55.25490.67.55.2551,022
20790.67.56.0/2290.67.56.1 to 90.67.59.25490.67.59.2551,022
20890.67.60.0/2290.67.60.1 to 90.67.63.25490.67.63.2551,022
20990.67.64.0/2290.67.64.1 to 90.67.67.25490.67.67.2551,022
21090.67.68.0/2290.67.68.1 to 90.67.71.25490.67.71.2551,022
21190.67.72.0/2290.67.72.1 to 90.67.75.25490.67.75.2551,022
21290.67.76.0/2290.67.76.1 to 90.67.79.25490.67.79.2551,022
21390.67.80.0/2290.67.80.1 to 90.67.83.25490.67.83.2551,022
21490.67.84.0/2290.67.84.1 to 90.67.87.25490.67.87.2551,022
21590.67.88.0/2290.67.88.1 to 90.67.91.25490.67.91.2551,022
21690.67.92.0/2290.67.92.1 to 90.67.95.25490.67.95.2551,022
21790.67.96.0/2290.67.96.1 to 90.67.99.25490.67.99.2551,022
21890.67.100.0/2290.67.100.1 to 90.67.103.25490.67.103.2551,022
21990.67.104.0/2290.67.104.1 to 90.67.107.25490.67.107.2551,022
22090.67.108.0/2290.67.108.1 to 90.67.111.25490.67.111.2551,022
22190.67.112.0/2290.67.112.1 to 90.67.115.25490.67.115.2551,022
22290.67.116.0/2290.67.116.1 to 90.67.119.25490.67.119.2551,022
22390.67.120.0/2290.67.120.1 to 90.67.123.25490.67.123.2551,022
22490.67.124.0/2290.67.124.1 to 90.67.127.25490.67.127.2551,022
22590.67.128.0/2290.67.128.1 to 90.67.131.25490.67.131.2551,022
22690.67.132.0/2290.67.132.1 to 90.67.135.25490.67.135.2551,022
22790.67.136.0/2290.67.136.1 to 90.67.139.25490.67.139.2551,022
22890.67.140.0/2290.67.140.1 to 90.67.143.25490.67.143.2551,022
22990.67.144.0/2290.67.144.1 to 90.67.147.25490.67.147.2551,022
23090.67.148.0/2290.67.148.1 to 90.67.151.25490.67.151.2551,022
23190.67.152.0/2290.67.152.1 to 90.67.155.25490.67.155.2551,022
23290.67.156.0/2290.67.156.1 to 90.67.159.25490.67.159.2551,022
23390.67.160.0/2290.67.160.1 to 90.67.163.25490.67.163.2551,022
23490.67.164.0/2290.67.164.1 to 90.67.167.25490.67.167.2551,022
23590.67.168.0/2290.67.168.1 to 90.67.171.25490.67.171.2551,022
23690.67.172.0/2290.67.172.1 to 90.67.175.25490.67.175.2551,022
23790.67.176.0/2290.67.176.1 to 90.67.179.25490.67.179.2551,022
23890.67.180.0/2290.67.180.1 to 90.67.183.25490.67.183.2551,022
23990.67.184.0/2290.67.184.1 to 90.67.187.25490.67.187.2551,022
24090.67.188.0/2290.67.188.1 to 90.67.191.25490.67.191.2551,022
24190.67.192.0/2290.67.192.1 to 90.67.195.25490.67.195.2551,022
24290.67.196.0/2290.67.196.1 to 90.67.199.25490.67.199.2551,022
24390.67.200.0/2290.67.200.1 to 90.67.203.25490.67.203.2551,022
24490.67.204.0/2290.67.204.1 to 90.67.207.25490.67.207.2551,022
24590.67.208.0/2290.67.208.1 to 90.67.211.25490.67.211.2551,022
24690.67.212.0/2290.67.212.1 to 90.67.215.25490.67.215.2551,022
24790.67.216.0/2290.67.216.1 to 90.67.219.25490.67.219.2551,022
24890.67.220.0/2290.67.220.1 to 90.67.223.25490.67.223.2551,022
24990.67.224.0/2290.67.224.1 to 90.67.227.25490.67.227.2551,022
25090.67.228.0/2290.67.228.1 to 90.67.231.25490.67.231.2551,022
25190.67.232.0/2290.67.232.1 to 90.67.235.25490.67.235.2551,022
25290.67.236.0/2290.67.236.1 to 90.67.239.25490.67.239.2551,022
25390.67.240.0/2290.67.240.1 to 90.67.243.25490.67.243.2551,022
25490.67.244.0/2290.67.244.1 to 90.67.247.25490.67.247.2551,022
25590.67.248.0/2290.67.248.1 to 90.67.251.25490.67.251.2551,022
25690.67.252.0/2290.67.252.1 to 90.67.255.25490.67.255.2551,022

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.