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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.

Network90.64.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
90.64.0.0
Broadcast address
90.95.255.255
First usable
90.64.0.1
Last usable
90.95.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
A (default /8)
As numbers
Hex 5A400000 · Integer 1514143744 to 1516240895
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
72.90.in-addr.arpa
73.90.in-addr.arpa
74.90.in-addr.arpa
75.90.in-addr.arpa
76.90.in-addr.arpa
77.90.in-addr.arpa
78.90.in-addr.arpa
79.90.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011010.01000000.00000000.0000000090.64.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network01011010.01000000.00000000.0000000090.64.0.0
Broadcast01011010.01011111.11111111.1111111190.95.255.255
Split into smaller subnets/21
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

90.64.0.0/11 makes 1,024 subnets of /21; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
190.64.0.0/2190.64.0.1 to 90.64.7.25490.64.7.2552,046
290.64.8.0/2190.64.8.1 to 90.64.15.25490.64.15.2552,046
390.64.16.0/2190.64.16.1 to 90.64.23.25490.64.23.2552,046
490.64.24.0/2190.64.24.1 to 90.64.31.25490.64.31.2552,046
590.64.32.0/2190.64.32.1 to 90.64.39.25490.64.39.2552,046
690.64.40.0/2190.64.40.1 to 90.64.47.25490.64.47.2552,046
790.64.48.0/2190.64.48.1 to 90.64.55.25490.64.55.2552,046
890.64.56.0/2190.64.56.1 to 90.64.63.25490.64.63.2552,046
990.64.64.0/2190.64.64.1 to 90.64.71.25490.64.71.2552,046
1090.64.72.0/2190.64.72.1 to 90.64.79.25490.64.79.2552,046
1190.64.80.0/2190.64.80.1 to 90.64.87.25490.64.87.2552,046
1290.64.88.0/2190.64.88.1 to 90.64.95.25490.64.95.2552,046
1390.64.96.0/2190.64.96.1 to 90.64.103.25490.64.103.2552,046
1490.64.104.0/2190.64.104.1 to 90.64.111.25490.64.111.2552,046
1590.64.112.0/2190.64.112.1 to 90.64.119.25490.64.119.2552,046
1690.64.120.0/2190.64.120.1 to 90.64.127.25490.64.127.2552,046
1790.64.128.0/2190.64.128.1 to 90.64.135.25490.64.135.2552,046
1890.64.136.0/2190.64.136.1 to 90.64.143.25490.64.143.2552,046
1990.64.144.0/2190.64.144.1 to 90.64.151.25490.64.151.2552,046
2090.64.152.0/2190.64.152.1 to 90.64.159.25490.64.159.2552,046
2190.64.160.0/2190.64.160.1 to 90.64.167.25490.64.167.2552,046
2290.64.168.0/2190.64.168.1 to 90.64.175.25490.64.175.2552,046
2390.64.176.0/2190.64.176.1 to 90.64.183.25490.64.183.2552,046
2490.64.184.0/2190.64.184.1 to 90.64.191.25490.64.191.2552,046
2590.64.192.0/2190.64.192.1 to 90.64.199.25490.64.199.2552,046
2690.64.200.0/2190.64.200.1 to 90.64.207.25490.64.207.2552,046
2790.64.208.0/2190.64.208.1 to 90.64.215.25490.64.215.2552,046
2890.64.216.0/2190.64.216.1 to 90.64.223.25490.64.223.2552,046
2990.64.224.0/2190.64.224.1 to 90.64.231.25490.64.231.2552,046
3090.64.232.0/2190.64.232.1 to 90.64.239.25490.64.239.2552,046
3190.64.240.0/2190.64.240.1 to 90.64.247.25490.64.247.2552,046
3290.64.248.0/2190.64.248.1 to 90.64.255.25490.64.255.2552,046
3390.65.0.0/2190.65.0.1 to 90.65.7.25490.65.7.2552,046
3490.65.8.0/2190.65.8.1 to 90.65.15.25490.65.15.2552,046
3590.65.16.0/2190.65.16.1 to 90.65.23.25490.65.23.2552,046
3690.65.24.0/2190.65.24.1 to 90.65.31.25490.65.31.2552,046
3790.65.32.0/2190.65.32.1 to 90.65.39.25490.65.39.2552,046
3890.65.40.0/2190.65.40.1 to 90.65.47.25490.65.47.2552,046
3990.65.48.0/2190.65.48.1 to 90.65.55.25490.65.55.2552,046
4090.65.56.0/2190.65.56.1 to 90.65.63.25490.65.63.2552,046
4190.65.64.0/2190.65.64.1 to 90.65.71.25490.65.71.2552,046
4290.65.72.0/2190.65.72.1 to 90.65.79.25490.65.79.2552,046
4390.65.80.0/2190.65.80.1 to 90.65.87.25490.65.87.2552,046
4490.65.88.0/2190.65.88.1 to 90.65.95.25490.65.95.2552,046
4590.65.96.0/2190.65.96.1 to 90.65.103.25490.65.103.2552,046
4690.65.104.0/2190.65.104.1 to 90.65.111.25490.65.111.2552,046
4790.65.112.0/2190.65.112.1 to 90.65.119.25490.65.119.2552,046
4890.65.120.0/2190.65.120.1 to 90.65.127.25490.65.127.2552,046
4990.65.128.0/2190.65.128.1 to 90.65.135.25490.65.135.2552,046
5090.65.136.0/2190.65.136.1 to 90.65.143.25490.65.143.2552,046
5190.65.144.0/2190.65.144.1 to 90.65.151.25490.65.151.2552,046
5290.65.152.0/2190.65.152.1 to 90.65.159.25490.65.159.2552,046
5390.65.160.0/2190.65.160.1 to 90.65.167.25490.65.167.2552,046
5490.65.168.0/2190.65.168.1 to 90.65.175.25490.65.175.2552,046
5590.65.176.0/2190.65.176.1 to 90.65.183.25490.65.183.2552,046
5690.65.184.0/2190.65.184.1 to 90.65.191.25490.65.191.2552,046
5790.65.192.0/2190.65.192.1 to 90.65.199.25490.65.199.2552,046
5890.65.200.0/2190.65.200.1 to 90.65.207.25490.65.207.2552,046
5990.65.208.0/2190.65.208.1 to 90.65.215.25490.65.215.2552,046
6090.65.216.0/2190.65.216.1 to 90.65.223.25490.65.223.2552,046
6190.65.224.0/2190.65.224.1 to 90.65.231.25490.65.231.2552,046
6290.65.232.0/2190.65.232.1 to 90.65.239.25490.65.239.2552,046
6390.65.240.0/2190.65.240.1 to 90.65.247.25490.65.247.2552,046
6490.65.248.0/2190.65.248.1 to 90.65.255.25490.65.255.2552,046
6590.66.0.0/2190.66.0.1 to 90.66.7.25490.66.7.2552,046
6690.66.8.0/2190.66.8.1 to 90.66.15.25490.66.15.2552,046
6790.66.16.0/2190.66.16.1 to 90.66.23.25490.66.23.2552,046
6890.66.24.0/2190.66.24.1 to 90.66.31.25490.66.31.2552,046
6990.66.32.0/2190.66.32.1 to 90.66.39.25490.66.39.2552,046
7090.66.40.0/2190.66.40.1 to 90.66.47.25490.66.47.2552,046
7190.66.48.0/2190.66.48.1 to 90.66.55.25490.66.55.2552,046
7290.66.56.0/2190.66.56.1 to 90.66.63.25490.66.63.2552,046
7390.66.64.0/2190.66.64.1 to 90.66.71.25490.66.71.2552,046
7490.66.72.0/2190.66.72.1 to 90.66.79.25490.66.79.2552,046
7590.66.80.0/2190.66.80.1 to 90.66.87.25490.66.87.2552,046
7690.66.88.0/2190.66.88.1 to 90.66.95.25490.66.95.2552,046
7790.66.96.0/2190.66.96.1 to 90.66.103.25490.66.103.2552,046
7890.66.104.0/2190.66.104.1 to 90.66.111.25490.66.111.2552,046
7990.66.112.0/2190.66.112.1 to 90.66.119.25490.66.119.2552,046
8090.66.120.0/2190.66.120.1 to 90.66.127.25490.66.127.2552,046
8190.66.128.0/2190.66.128.1 to 90.66.135.25490.66.135.2552,046
8290.66.136.0/2190.66.136.1 to 90.66.143.25490.66.143.2552,046
8390.66.144.0/2190.66.144.1 to 90.66.151.25490.66.151.2552,046
8490.66.152.0/2190.66.152.1 to 90.66.159.25490.66.159.2552,046
8590.66.160.0/2190.66.160.1 to 90.66.167.25490.66.167.2552,046
8690.66.168.0/2190.66.168.1 to 90.66.175.25490.66.175.2552,046
8790.66.176.0/2190.66.176.1 to 90.66.183.25490.66.183.2552,046
8890.66.184.0/2190.66.184.1 to 90.66.191.25490.66.191.2552,046
8990.66.192.0/2190.66.192.1 to 90.66.199.25490.66.199.2552,046
9090.66.200.0/2190.66.200.1 to 90.66.207.25490.66.207.2552,046
9190.66.208.0/2190.66.208.1 to 90.66.215.25490.66.215.2552,046
9290.66.216.0/2190.66.216.1 to 90.66.223.25490.66.223.2552,046
9390.66.224.0/2190.66.224.1 to 90.66.231.25490.66.231.2552,046
9490.66.232.0/2190.66.232.1 to 90.66.239.25490.66.239.2552,046
9590.66.240.0/2190.66.240.1 to 90.66.247.25490.66.247.2552,046
9690.66.248.0/2190.66.248.1 to 90.66.255.25490.66.255.2552,046
9790.67.0.0/2190.67.0.1 to 90.67.7.25490.67.7.2552,046
9890.67.8.0/2190.67.8.1 to 90.67.15.25490.67.15.2552,046
9990.67.16.0/2190.67.16.1 to 90.67.23.25490.67.23.2552,046
10090.67.24.0/2190.67.24.1 to 90.67.31.25490.67.31.2552,046
10190.67.32.0/2190.67.32.1 to 90.67.39.25490.67.39.2552,046
10290.67.40.0/2190.67.40.1 to 90.67.47.25490.67.47.2552,046
10390.67.48.0/2190.67.48.1 to 90.67.55.25490.67.55.2552,046
10490.67.56.0/2190.67.56.1 to 90.67.63.25490.67.63.2552,046
10590.67.64.0/2190.67.64.1 to 90.67.71.25490.67.71.2552,046
10690.67.72.0/2190.67.72.1 to 90.67.79.25490.67.79.2552,046
10790.67.80.0/2190.67.80.1 to 90.67.87.25490.67.87.2552,046
10890.67.88.0/2190.67.88.1 to 90.67.95.25490.67.95.2552,046
10990.67.96.0/2190.67.96.1 to 90.67.103.25490.67.103.2552,046
11090.67.104.0/2190.67.104.1 to 90.67.111.25490.67.111.2552,046
11190.67.112.0/2190.67.112.1 to 90.67.119.25490.67.119.2552,046
11290.67.120.0/2190.67.120.1 to 90.67.127.25490.67.127.2552,046
11390.67.128.0/2190.67.128.1 to 90.67.135.25490.67.135.2552,046
11490.67.136.0/2190.67.136.1 to 90.67.143.25490.67.143.2552,046
11590.67.144.0/2190.67.144.1 to 90.67.151.25490.67.151.2552,046
11690.67.152.0/2190.67.152.1 to 90.67.159.25490.67.159.2552,046
11790.67.160.0/2190.67.160.1 to 90.67.167.25490.67.167.2552,046
11890.67.168.0/2190.67.168.1 to 90.67.175.25490.67.175.2552,046
11990.67.176.0/2190.67.176.1 to 90.67.183.25490.67.183.2552,046
12090.67.184.0/2190.67.184.1 to 90.67.191.25490.67.191.2552,046
12190.67.192.0/2190.67.192.1 to 90.67.199.25490.67.199.2552,046
12290.67.200.0/2190.67.200.1 to 90.67.207.25490.67.207.2552,046
12390.67.208.0/2190.67.208.1 to 90.67.215.25490.67.215.2552,046
12490.67.216.0/2190.67.216.1 to 90.67.223.25490.67.223.2552,046
12590.67.224.0/2190.67.224.1 to 90.67.231.25490.67.231.2552,046
12690.67.232.0/2190.67.232.1 to 90.67.239.25490.67.239.2552,046
12790.67.240.0/2190.67.240.1 to 90.67.247.25490.67.247.2552,046
12890.67.248.0/2190.67.248.1 to 90.67.255.25490.67.255.2552,046
12990.68.0.0/2190.68.0.1 to 90.68.7.25490.68.7.2552,046
13090.68.8.0/2190.68.8.1 to 90.68.15.25490.68.15.2552,046
13190.68.16.0/2190.68.16.1 to 90.68.23.25490.68.23.2552,046
13290.68.24.0/2190.68.24.1 to 90.68.31.25490.68.31.2552,046
13390.68.32.0/2190.68.32.1 to 90.68.39.25490.68.39.2552,046
13490.68.40.0/2190.68.40.1 to 90.68.47.25490.68.47.2552,046
13590.68.48.0/2190.68.48.1 to 90.68.55.25490.68.55.2552,046
13690.68.56.0/2190.68.56.1 to 90.68.63.25490.68.63.2552,046
13790.68.64.0/2190.68.64.1 to 90.68.71.25490.68.71.2552,046
13890.68.72.0/2190.68.72.1 to 90.68.79.25490.68.79.2552,046
13990.68.80.0/2190.68.80.1 to 90.68.87.25490.68.87.2552,046
14090.68.88.0/2190.68.88.1 to 90.68.95.25490.68.95.2552,046
14190.68.96.0/2190.68.96.1 to 90.68.103.25490.68.103.2552,046
14290.68.104.0/2190.68.104.1 to 90.68.111.25490.68.111.2552,046
14390.68.112.0/2190.68.112.1 to 90.68.119.25490.68.119.2552,046
14490.68.120.0/2190.68.120.1 to 90.68.127.25490.68.127.2552,046
14590.68.128.0/2190.68.128.1 to 90.68.135.25490.68.135.2552,046
14690.68.136.0/2190.68.136.1 to 90.68.143.25490.68.143.2552,046
14790.68.144.0/2190.68.144.1 to 90.68.151.25490.68.151.2552,046
14890.68.152.0/2190.68.152.1 to 90.68.159.25490.68.159.2552,046
14990.68.160.0/2190.68.160.1 to 90.68.167.25490.68.167.2552,046
15090.68.168.0/2190.68.168.1 to 90.68.175.25490.68.175.2552,046
15190.68.176.0/2190.68.176.1 to 90.68.183.25490.68.183.2552,046
15290.68.184.0/2190.68.184.1 to 90.68.191.25490.68.191.2552,046
15390.68.192.0/2190.68.192.1 to 90.68.199.25490.68.199.2552,046
15490.68.200.0/2190.68.200.1 to 90.68.207.25490.68.207.2552,046
15590.68.208.0/2190.68.208.1 to 90.68.215.25490.68.215.2552,046
15690.68.216.0/2190.68.216.1 to 90.68.223.25490.68.223.2552,046
15790.68.224.0/2190.68.224.1 to 90.68.231.25490.68.231.2552,046
15890.68.232.0/2190.68.232.1 to 90.68.239.25490.68.239.2552,046
15990.68.240.0/2190.68.240.1 to 90.68.247.25490.68.247.2552,046
16090.68.248.0/2190.68.248.1 to 90.68.255.25490.68.255.2552,046
16190.69.0.0/2190.69.0.1 to 90.69.7.25490.69.7.2552,046
16290.69.8.0/2190.69.8.1 to 90.69.15.25490.69.15.2552,046
16390.69.16.0/2190.69.16.1 to 90.69.23.25490.69.23.2552,046
16490.69.24.0/2190.69.24.1 to 90.69.31.25490.69.31.2552,046
16590.69.32.0/2190.69.32.1 to 90.69.39.25490.69.39.2552,046
16690.69.40.0/2190.69.40.1 to 90.69.47.25490.69.47.2552,046
16790.69.48.0/2190.69.48.1 to 90.69.55.25490.69.55.2552,046
16890.69.56.0/2190.69.56.1 to 90.69.63.25490.69.63.2552,046
16990.69.64.0/2190.69.64.1 to 90.69.71.25490.69.71.2552,046
17090.69.72.0/2190.69.72.1 to 90.69.79.25490.69.79.2552,046
17190.69.80.0/2190.69.80.1 to 90.69.87.25490.69.87.2552,046
17290.69.88.0/2190.69.88.1 to 90.69.95.25490.69.95.2552,046
17390.69.96.0/2190.69.96.1 to 90.69.103.25490.69.103.2552,046
17490.69.104.0/2190.69.104.1 to 90.69.111.25490.69.111.2552,046
17590.69.112.0/2190.69.112.1 to 90.69.119.25490.69.119.2552,046
17690.69.120.0/2190.69.120.1 to 90.69.127.25490.69.127.2552,046
17790.69.128.0/2190.69.128.1 to 90.69.135.25490.69.135.2552,046
17890.69.136.0/2190.69.136.1 to 90.69.143.25490.69.143.2552,046
17990.69.144.0/2190.69.144.1 to 90.69.151.25490.69.151.2552,046
18090.69.152.0/2190.69.152.1 to 90.69.159.25490.69.159.2552,046
18190.69.160.0/2190.69.160.1 to 90.69.167.25490.69.167.2552,046
18290.69.168.0/2190.69.168.1 to 90.69.175.25490.69.175.2552,046
18390.69.176.0/2190.69.176.1 to 90.69.183.25490.69.183.2552,046
18490.69.184.0/2190.69.184.1 to 90.69.191.25490.69.191.2552,046
18590.69.192.0/2190.69.192.1 to 90.69.199.25490.69.199.2552,046
18690.69.200.0/2190.69.200.1 to 90.69.207.25490.69.207.2552,046
18790.69.208.0/2190.69.208.1 to 90.69.215.25490.69.215.2552,046
18890.69.216.0/2190.69.216.1 to 90.69.223.25490.69.223.2552,046
18990.69.224.0/2190.69.224.1 to 90.69.231.25490.69.231.2552,046
19090.69.232.0/2190.69.232.1 to 90.69.239.25490.69.239.2552,046
19190.69.240.0/2190.69.240.1 to 90.69.247.25490.69.247.2552,046
19290.69.248.0/2190.69.248.1 to 90.69.255.25490.69.255.2552,046
19390.70.0.0/2190.70.0.1 to 90.70.7.25490.70.7.2552,046
19490.70.8.0/2190.70.8.1 to 90.70.15.25490.70.15.2552,046
19590.70.16.0/2190.70.16.1 to 90.70.23.25490.70.23.2552,046
19690.70.24.0/2190.70.24.1 to 90.70.31.25490.70.31.2552,046
19790.70.32.0/2190.70.32.1 to 90.70.39.25490.70.39.2552,046
19890.70.40.0/2190.70.40.1 to 90.70.47.25490.70.47.2552,046
19990.70.48.0/2190.70.48.1 to 90.70.55.25490.70.55.2552,046
20090.70.56.0/2190.70.56.1 to 90.70.63.25490.70.63.2552,046
20190.70.64.0/2190.70.64.1 to 90.70.71.25490.70.71.2552,046
20290.70.72.0/2190.70.72.1 to 90.70.79.25490.70.79.2552,046
20390.70.80.0/2190.70.80.1 to 90.70.87.25490.70.87.2552,046
20490.70.88.0/2190.70.88.1 to 90.70.95.25490.70.95.2552,046
20590.70.96.0/2190.70.96.1 to 90.70.103.25490.70.103.2552,046
20690.70.104.0/2190.70.104.1 to 90.70.111.25490.70.111.2552,046
20790.70.112.0/2190.70.112.1 to 90.70.119.25490.70.119.2552,046
20890.70.120.0/2190.70.120.1 to 90.70.127.25490.70.127.2552,046
20990.70.128.0/2190.70.128.1 to 90.70.135.25490.70.135.2552,046
21090.70.136.0/2190.70.136.1 to 90.70.143.25490.70.143.2552,046
21190.70.144.0/2190.70.144.1 to 90.70.151.25490.70.151.2552,046
21290.70.152.0/2190.70.152.1 to 90.70.159.25490.70.159.2552,046
21390.70.160.0/2190.70.160.1 to 90.70.167.25490.70.167.2552,046
21490.70.168.0/2190.70.168.1 to 90.70.175.25490.70.175.2552,046
21590.70.176.0/2190.70.176.1 to 90.70.183.25490.70.183.2552,046
21690.70.184.0/2190.70.184.1 to 90.70.191.25490.70.191.2552,046
21790.70.192.0/2190.70.192.1 to 90.70.199.25490.70.199.2552,046
21890.70.200.0/2190.70.200.1 to 90.70.207.25490.70.207.2552,046
21990.70.208.0/2190.70.208.1 to 90.70.215.25490.70.215.2552,046
22090.70.216.0/2190.70.216.1 to 90.70.223.25490.70.223.2552,046
22190.70.224.0/2190.70.224.1 to 90.70.231.25490.70.231.2552,046
22290.70.232.0/2190.70.232.1 to 90.70.239.25490.70.239.2552,046
22390.70.240.0/2190.70.240.1 to 90.70.247.25490.70.247.2552,046
22490.70.248.0/2190.70.248.1 to 90.70.255.25490.70.255.2552,046
22590.71.0.0/2190.71.0.1 to 90.71.7.25490.71.7.2552,046
22690.71.8.0/2190.71.8.1 to 90.71.15.25490.71.15.2552,046
22790.71.16.0/2190.71.16.1 to 90.71.23.25490.71.23.2552,046
22890.71.24.0/2190.71.24.1 to 90.71.31.25490.71.31.2552,046
22990.71.32.0/2190.71.32.1 to 90.71.39.25490.71.39.2552,046
23090.71.40.0/2190.71.40.1 to 90.71.47.25490.71.47.2552,046
23190.71.48.0/2190.71.48.1 to 90.71.55.25490.71.55.2552,046
23290.71.56.0/2190.71.56.1 to 90.71.63.25490.71.63.2552,046
23390.71.64.0/2190.71.64.1 to 90.71.71.25490.71.71.2552,046
23490.71.72.0/2190.71.72.1 to 90.71.79.25490.71.79.2552,046
23590.71.80.0/2190.71.80.1 to 90.71.87.25490.71.87.2552,046
23690.71.88.0/2190.71.88.1 to 90.71.95.25490.71.95.2552,046
23790.71.96.0/2190.71.96.1 to 90.71.103.25490.71.103.2552,046
23890.71.104.0/2190.71.104.1 to 90.71.111.25490.71.111.2552,046
23990.71.112.0/2190.71.112.1 to 90.71.119.25490.71.119.2552,046
24090.71.120.0/2190.71.120.1 to 90.71.127.25490.71.127.2552,046
24190.71.128.0/2190.71.128.1 to 90.71.135.25490.71.135.2552,046
24290.71.136.0/2190.71.136.1 to 90.71.143.25490.71.143.2552,046
24390.71.144.0/2190.71.144.1 to 90.71.151.25490.71.151.2552,046
24490.71.152.0/2190.71.152.1 to 90.71.159.25490.71.159.2552,046
24590.71.160.0/2190.71.160.1 to 90.71.167.25490.71.167.2552,046
24690.71.168.0/2190.71.168.1 to 90.71.175.25490.71.175.2552,046
24790.71.176.0/2190.71.176.1 to 90.71.183.25490.71.183.2552,046
24890.71.184.0/2190.71.184.1 to 90.71.191.25490.71.191.2552,046
24990.71.192.0/2190.71.192.1 to 90.71.199.25490.71.199.2552,046
25090.71.200.0/2190.71.200.1 to 90.71.207.25490.71.207.2552,046
25190.71.208.0/2190.71.208.1 to 90.71.215.25490.71.215.2552,046
25290.71.216.0/2190.71.216.1 to 90.71.223.25490.71.223.2552,046
25390.71.224.0/2190.71.224.1 to 90.71.231.25490.71.231.2552,046
25490.71.232.0/2190.71.232.1 to 90.71.239.25490.71.239.2552,046
25590.71.240.0/2190.71.240.1 to 90.71.247.25490.71.247.2552,046
25690.71.248.0/2190.71.248.1 to 90.71.255.25490.71.255.2552,046

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.