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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.

Network90.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
90.0.0.0
Broadcast address
90.127.255.255
First usable
90.0.0.1
Last usable
90.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 5A000000 · Integer 1509949440 to 1518338047
Reverse DNS zones
0.90.in-addr.arpa
1.90.in-addr.arpa
2.90.in-addr.arpa
3.90.in-addr.arpa
4.90.in-addr.arpa
5.90.in-addr.arpa
6.90.in-addr.arpa
7.90.in-addr.arpa
8.90.in-addr.arpa
9.90.in-addr.arpa
10.90.in-addr.arpa
11.90.in-addr.arpa
12.90.in-addr.arpa
13.90.in-addr.arpa
14.90.in-addr.arpa
15.90.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011010.00000000.00000000.0000000090.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01011010.00000000.00000000.0000000090.0.0.0
Broadcast01011010.01111111.11111111.1111111190.127.255.255
Split into smaller subnets/20
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

90.0.0.0/9 makes 2,048 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
190.0.0.0/2090.0.0.1 to 90.0.15.25490.0.15.2554,094
290.0.16.0/2090.0.16.1 to 90.0.31.25490.0.31.2554,094
390.0.32.0/2090.0.32.1 to 90.0.47.25490.0.47.2554,094
490.0.48.0/2090.0.48.1 to 90.0.63.25490.0.63.2554,094
590.0.64.0/2090.0.64.1 to 90.0.79.25490.0.79.2554,094
690.0.80.0/2090.0.80.1 to 90.0.95.25490.0.95.2554,094
790.0.96.0/2090.0.96.1 to 90.0.111.25490.0.111.2554,094
890.0.112.0/2090.0.112.1 to 90.0.127.25490.0.127.2554,094
990.0.128.0/2090.0.128.1 to 90.0.143.25490.0.143.2554,094
1090.0.144.0/2090.0.144.1 to 90.0.159.25490.0.159.2554,094
1190.0.160.0/2090.0.160.1 to 90.0.175.25490.0.175.2554,094
1290.0.176.0/2090.0.176.1 to 90.0.191.25490.0.191.2554,094
1390.0.192.0/2090.0.192.1 to 90.0.207.25490.0.207.2554,094
1490.0.208.0/2090.0.208.1 to 90.0.223.25490.0.223.2554,094
1590.0.224.0/2090.0.224.1 to 90.0.239.25490.0.239.2554,094
1690.0.240.0/2090.0.240.1 to 90.0.255.25490.0.255.2554,094
1790.1.0.0/2090.1.0.1 to 90.1.15.25490.1.15.2554,094
1890.1.16.0/2090.1.16.1 to 90.1.31.25490.1.31.2554,094
1990.1.32.0/2090.1.32.1 to 90.1.47.25490.1.47.2554,094
2090.1.48.0/2090.1.48.1 to 90.1.63.25490.1.63.2554,094
2190.1.64.0/2090.1.64.1 to 90.1.79.25490.1.79.2554,094
2290.1.80.0/2090.1.80.1 to 90.1.95.25490.1.95.2554,094
2390.1.96.0/2090.1.96.1 to 90.1.111.25490.1.111.2554,094
2490.1.112.0/2090.1.112.1 to 90.1.127.25490.1.127.2554,094
2590.1.128.0/2090.1.128.1 to 90.1.143.25490.1.143.2554,094
2690.1.144.0/2090.1.144.1 to 90.1.159.25490.1.159.2554,094
2790.1.160.0/2090.1.160.1 to 90.1.175.25490.1.175.2554,094
2890.1.176.0/2090.1.176.1 to 90.1.191.25490.1.191.2554,094
2990.1.192.0/2090.1.192.1 to 90.1.207.25490.1.207.2554,094
3090.1.208.0/2090.1.208.1 to 90.1.223.25490.1.223.2554,094
3190.1.224.0/2090.1.224.1 to 90.1.239.25490.1.239.2554,094
3290.1.240.0/2090.1.240.1 to 90.1.255.25490.1.255.2554,094
3390.2.0.0/2090.2.0.1 to 90.2.15.25490.2.15.2554,094
3490.2.16.0/2090.2.16.1 to 90.2.31.25490.2.31.2554,094
3590.2.32.0/2090.2.32.1 to 90.2.47.25490.2.47.2554,094
3690.2.48.0/2090.2.48.1 to 90.2.63.25490.2.63.2554,094
3790.2.64.0/2090.2.64.1 to 90.2.79.25490.2.79.2554,094
3890.2.80.0/2090.2.80.1 to 90.2.95.25490.2.95.2554,094
3990.2.96.0/2090.2.96.1 to 90.2.111.25490.2.111.2554,094
4090.2.112.0/2090.2.112.1 to 90.2.127.25490.2.127.2554,094
4190.2.128.0/2090.2.128.1 to 90.2.143.25490.2.143.2554,094
4290.2.144.0/2090.2.144.1 to 90.2.159.25490.2.159.2554,094
4390.2.160.0/2090.2.160.1 to 90.2.175.25490.2.175.2554,094
4490.2.176.0/2090.2.176.1 to 90.2.191.25490.2.191.2554,094
4590.2.192.0/2090.2.192.1 to 90.2.207.25490.2.207.2554,094
4690.2.208.0/2090.2.208.1 to 90.2.223.25490.2.223.2554,094
4790.2.224.0/2090.2.224.1 to 90.2.239.25490.2.239.2554,094
4890.2.240.0/2090.2.240.1 to 90.2.255.25490.2.255.2554,094
4990.3.0.0/2090.3.0.1 to 90.3.15.25490.3.15.2554,094
5090.3.16.0/2090.3.16.1 to 90.3.31.25490.3.31.2554,094
5190.3.32.0/2090.3.32.1 to 90.3.47.25490.3.47.2554,094
5290.3.48.0/2090.3.48.1 to 90.3.63.25490.3.63.2554,094
5390.3.64.0/2090.3.64.1 to 90.3.79.25490.3.79.2554,094
5490.3.80.0/2090.3.80.1 to 90.3.95.25490.3.95.2554,094
5590.3.96.0/2090.3.96.1 to 90.3.111.25490.3.111.2554,094
5690.3.112.0/2090.3.112.1 to 90.3.127.25490.3.127.2554,094
5790.3.128.0/2090.3.128.1 to 90.3.143.25490.3.143.2554,094
5890.3.144.0/2090.3.144.1 to 90.3.159.25490.3.159.2554,094
5990.3.160.0/2090.3.160.1 to 90.3.175.25490.3.175.2554,094
6090.3.176.0/2090.3.176.1 to 90.3.191.25490.3.191.2554,094
6190.3.192.0/2090.3.192.1 to 90.3.207.25490.3.207.2554,094
6290.3.208.0/2090.3.208.1 to 90.3.223.25490.3.223.2554,094
6390.3.224.0/2090.3.224.1 to 90.3.239.25490.3.239.2554,094
6490.3.240.0/2090.3.240.1 to 90.3.255.25490.3.255.2554,094
6590.4.0.0/2090.4.0.1 to 90.4.15.25490.4.15.2554,094
6690.4.16.0/2090.4.16.1 to 90.4.31.25490.4.31.2554,094
6790.4.32.0/2090.4.32.1 to 90.4.47.25490.4.47.2554,094
6890.4.48.0/2090.4.48.1 to 90.4.63.25490.4.63.2554,094
6990.4.64.0/2090.4.64.1 to 90.4.79.25490.4.79.2554,094
7090.4.80.0/2090.4.80.1 to 90.4.95.25490.4.95.2554,094
7190.4.96.0/2090.4.96.1 to 90.4.111.25490.4.111.2554,094
7290.4.112.0/2090.4.112.1 to 90.4.127.25490.4.127.2554,094
7390.4.128.0/2090.4.128.1 to 90.4.143.25490.4.143.2554,094
7490.4.144.0/2090.4.144.1 to 90.4.159.25490.4.159.2554,094
7590.4.160.0/2090.4.160.1 to 90.4.175.25490.4.175.2554,094
7690.4.176.0/2090.4.176.1 to 90.4.191.25490.4.191.2554,094
7790.4.192.0/2090.4.192.1 to 90.4.207.25490.4.207.2554,094
7890.4.208.0/2090.4.208.1 to 90.4.223.25490.4.223.2554,094
7990.4.224.0/2090.4.224.1 to 90.4.239.25490.4.239.2554,094
8090.4.240.0/2090.4.240.1 to 90.4.255.25490.4.255.2554,094
8190.5.0.0/2090.5.0.1 to 90.5.15.25490.5.15.2554,094
8290.5.16.0/2090.5.16.1 to 90.5.31.25490.5.31.2554,094
8390.5.32.0/2090.5.32.1 to 90.5.47.25490.5.47.2554,094
8490.5.48.0/2090.5.48.1 to 90.5.63.25490.5.63.2554,094
8590.5.64.0/2090.5.64.1 to 90.5.79.25490.5.79.2554,094
8690.5.80.0/2090.5.80.1 to 90.5.95.25490.5.95.2554,094
8790.5.96.0/2090.5.96.1 to 90.5.111.25490.5.111.2554,094
8890.5.112.0/2090.5.112.1 to 90.5.127.25490.5.127.2554,094
8990.5.128.0/2090.5.128.1 to 90.5.143.25490.5.143.2554,094
9090.5.144.0/2090.5.144.1 to 90.5.159.25490.5.159.2554,094
9190.5.160.0/2090.5.160.1 to 90.5.175.25490.5.175.2554,094
9290.5.176.0/2090.5.176.1 to 90.5.191.25490.5.191.2554,094
9390.5.192.0/2090.5.192.1 to 90.5.207.25490.5.207.2554,094
9490.5.208.0/2090.5.208.1 to 90.5.223.25490.5.223.2554,094
9590.5.224.0/2090.5.224.1 to 90.5.239.25490.5.239.2554,094
9690.5.240.0/2090.5.240.1 to 90.5.255.25490.5.255.2554,094
9790.6.0.0/2090.6.0.1 to 90.6.15.25490.6.15.2554,094
9890.6.16.0/2090.6.16.1 to 90.6.31.25490.6.31.2554,094
9990.6.32.0/2090.6.32.1 to 90.6.47.25490.6.47.2554,094
10090.6.48.0/2090.6.48.1 to 90.6.63.25490.6.63.2554,094
10190.6.64.0/2090.6.64.1 to 90.6.79.25490.6.79.2554,094
10290.6.80.0/2090.6.80.1 to 90.6.95.25490.6.95.2554,094
10390.6.96.0/2090.6.96.1 to 90.6.111.25490.6.111.2554,094
10490.6.112.0/2090.6.112.1 to 90.6.127.25490.6.127.2554,094
10590.6.128.0/2090.6.128.1 to 90.6.143.25490.6.143.2554,094
10690.6.144.0/2090.6.144.1 to 90.6.159.25490.6.159.2554,094
10790.6.160.0/2090.6.160.1 to 90.6.175.25490.6.175.2554,094
10890.6.176.0/2090.6.176.1 to 90.6.191.25490.6.191.2554,094
10990.6.192.0/2090.6.192.1 to 90.6.207.25490.6.207.2554,094
11090.6.208.0/2090.6.208.1 to 90.6.223.25490.6.223.2554,094
11190.6.224.0/2090.6.224.1 to 90.6.239.25490.6.239.2554,094
11290.6.240.0/2090.6.240.1 to 90.6.255.25490.6.255.2554,094
11390.7.0.0/2090.7.0.1 to 90.7.15.25490.7.15.2554,094
11490.7.16.0/2090.7.16.1 to 90.7.31.25490.7.31.2554,094
11590.7.32.0/2090.7.32.1 to 90.7.47.25490.7.47.2554,094
11690.7.48.0/2090.7.48.1 to 90.7.63.25490.7.63.2554,094
11790.7.64.0/2090.7.64.1 to 90.7.79.25490.7.79.2554,094
11890.7.80.0/2090.7.80.1 to 90.7.95.25490.7.95.2554,094
11990.7.96.0/2090.7.96.1 to 90.7.111.25490.7.111.2554,094
12090.7.112.0/2090.7.112.1 to 90.7.127.25490.7.127.2554,094
12190.7.128.0/2090.7.128.1 to 90.7.143.25490.7.143.2554,094
12290.7.144.0/2090.7.144.1 to 90.7.159.25490.7.159.2554,094
12390.7.160.0/2090.7.160.1 to 90.7.175.25490.7.175.2554,094
12490.7.176.0/2090.7.176.1 to 90.7.191.25490.7.191.2554,094
12590.7.192.0/2090.7.192.1 to 90.7.207.25490.7.207.2554,094
12690.7.208.0/2090.7.208.1 to 90.7.223.25490.7.223.2554,094
12790.7.224.0/2090.7.224.1 to 90.7.239.25490.7.239.2554,094
12890.7.240.0/2090.7.240.1 to 90.7.255.25490.7.255.2554,094
12990.8.0.0/2090.8.0.1 to 90.8.15.25490.8.15.2554,094
13090.8.16.0/2090.8.16.1 to 90.8.31.25490.8.31.2554,094
13190.8.32.0/2090.8.32.1 to 90.8.47.25490.8.47.2554,094
13290.8.48.0/2090.8.48.1 to 90.8.63.25490.8.63.2554,094
13390.8.64.0/2090.8.64.1 to 90.8.79.25490.8.79.2554,094
13490.8.80.0/2090.8.80.1 to 90.8.95.25490.8.95.2554,094
13590.8.96.0/2090.8.96.1 to 90.8.111.25490.8.111.2554,094
13690.8.112.0/2090.8.112.1 to 90.8.127.25490.8.127.2554,094
13790.8.128.0/2090.8.128.1 to 90.8.143.25490.8.143.2554,094
13890.8.144.0/2090.8.144.1 to 90.8.159.25490.8.159.2554,094
13990.8.160.0/2090.8.160.1 to 90.8.175.25490.8.175.2554,094
14090.8.176.0/2090.8.176.1 to 90.8.191.25490.8.191.2554,094
14190.8.192.0/2090.8.192.1 to 90.8.207.25490.8.207.2554,094
14290.8.208.0/2090.8.208.1 to 90.8.223.25490.8.223.2554,094
14390.8.224.0/2090.8.224.1 to 90.8.239.25490.8.239.2554,094
14490.8.240.0/2090.8.240.1 to 90.8.255.25490.8.255.2554,094
14590.9.0.0/2090.9.0.1 to 90.9.15.25490.9.15.2554,094
14690.9.16.0/2090.9.16.1 to 90.9.31.25490.9.31.2554,094
14790.9.32.0/2090.9.32.1 to 90.9.47.25490.9.47.2554,094
14890.9.48.0/2090.9.48.1 to 90.9.63.25490.9.63.2554,094
14990.9.64.0/2090.9.64.1 to 90.9.79.25490.9.79.2554,094
15090.9.80.0/2090.9.80.1 to 90.9.95.25490.9.95.2554,094
15190.9.96.0/2090.9.96.1 to 90.9.111.25490.9.111.2554,094
15290.9.112.0/2090.9.112.1 to 90.9.127.25490.9.127.2554,094
15390.9.128.0/2090.9.128.1 to 90.9.143.25490.9.143.2554,094
15490.9.144.0/2090.9.144.1 to 90.9.159.25490.9.159.2554,094
15590.9.160.0/2090.9.160.1 to 90.9.175.25490.9.175.2554,094
15690.9.176.0/2090.9.176.1 to 90.9.191.25490.9.191.2554,094
15790.9.192.0/2090.9.192.1 to 90.9.207.25490.9.207.2554,094
15890.9.208.0/2090.9.208.1 to 90.9.223.25490.9.223.2554,094
15990.9.224.0/2090.9.224.1 to 90.9.239.25490.9.239.2554,094
16090.9.240.0/2090.9.240.1 to 90.9.255.25490.9.255.2554,094
16190.10.0.0/2090.10.0.1 to 90.10.15.25490.10.15.2554,094
16290.10.16.0/2090.10.16.1 to 90.10.31.25490.10.31.2554,094
16390.10.32.0/2090.10.32.1 to 90.10.47.25490.10.47.2554,094
16490.10.48.0/2090.10.48.1 to 90.10.63.25490.10.63.2554,094
16590.10.64.0/2090.10.64.1 to 90.10.79.25490.10.79.2554,094
16690.10.80.0/2090.10.80.1 to 90.10.95.25490.10.95.2554,094
16790.10.96.0/2090.10.96.1 to 90.10.111.25490.10.111.2554,094
16890.10.112.0/2090.10.112.1 to 90.10.127.25490.10.127.2554,094
16990.10.128.0/2090.10.128.1 to 90.10.143.25490.10.143.2554,094
17090.10.144.0/2090.10.144.1 to 90.10.159.25490.10.159.2554,094
17190.10.160.0/2090.10.160.1 to 90.10.175.25490.10.175.2554,094
17290.10.176.0/2090.10.176.1 to 90.10.191.25490.10.191.2554,094
17390.10.192.0/2090.10.192.1 to 90.10.207.25490.10.207.2554,094
17490.10.208.0/2090.10.208.1 to 90.10.223.25490.10.223.2554,094
17590.10.224.0/2090.10.224.1 to 90.10.239.25490.10.239.2554,094
17690.10.240.0/2090.10.240.1 to 90.10.255.25490.10.255.2554,094
17790.11.0.0/2090.11.0.1 to 90.11.15.25490.11.15.2554,094
17890.11.16.0/2090.11.16.1 to 90.11.31.25490.11.31.2554,094
17990.11.32.0/2090.11.32.1 to 90.11.47.25490.11.47.2554,094
18090.11.48.0/2090.11.48.1 to 90.11.63.25490.11.63.2554,094
18190.11.64.0/2090.11.64.1 to 90.11.79.25490.11.79.2554,094
18290.11.80.0/2090.11.80.1 to 90.11.95.25490.11.95.2554,094
18390.11.96.0/2090.11.96.1 to 90.11.111.25490.11.111.2554,094
18490.11.112.0/2090.11.112.1 to 90.11.127.25490.11.127.2554,094
18590.11.128.0/2090.11.128.1 to 90.11.143.25490.11.143.2554,094
18690.11.144.0/2090.11.144.1 to 90.11.159.25490.11.159.2554,094
18790.11.160.0/2090.11.160.1 to 90.11.175.25490.11.175.2554,094
18890.11.176.0/2090.11.176.1 to 90.11.191.25490.11.191.2554,094
18990.11.192.0/2090.11.192.1 to 90.11.207.25490.11.207.2554,094
19090.11.208.0/2090.11.208.1 to 90.11.223.25490.11.223.2554,094
19190.11.224.0/2090.11.224.1 to 90.11.239.25490.11.239.2554,094
19290.11.240.0/2090.11.240.1 to 90.11.255.25490.11.255.2554,094
19390.12.0.0/2090.12.0.1 to 90.12.15.25490.12.15.2554,094
19490.12.16.0/2090.12.16.1 to 90.12.31.25490.12.31.2554,094
19590.12.32.0/2090.12.32.1 to 90.12.47.25490.12.47.2554,094
19690.12.48.0/2090.12.48.1 to 90.12.63.25490.12.63.2554,094
19790.12.64.0/2090.12.64.1 to 90.12.79.25490.12.79.2554,094
19890.12.80.0/2090.12.80.1 to 90.12.95.25490.12.95.2554,094
19990.12.96.0/2090.12.96.1 to 90.12.111.25490.12.111.2554,094
20090.12.112.0/2090.12.112.1 to 90.12.127.25490.12.127.2554,094
20190.12.128.0/2090.12.128.1 to 90.12.143.25490.12.143.2554,094
20290.12.144.0/2090.12.144.1 to 90.12.159.25490.12.159.2554,094
20390.12.160.0/2090.12.160.1 to 90.12.175.25490.12.175.2554,094
20490.12.176.0/2090.12.176.1 to 90.12.191.25490.12.191.2554,094
20590.12.192.0/2090.12.192.1 to 90.12.207.25490.12.207.2554,094
20690.12.208.0/2090.12.208.1 to 90.12.223.25490.12.223.2554,094
20790.12.224.0/2090.12.224.1 to 90.12.239.25490.12.239.2554,094
20890.12.240.0/2090.12.240.1 to 90.12.255.25490.12.255.2554,094
20990.13.0.0/2090.13.0.1 to 90.13.15.25490.13.15.2554,094
21090.13.16.0/2090.13.16.1 to 90.13.31.25490.13.31.2554,094
21190.13.32.0/2090.13.32.1 to 90.13.47.25490.13.47.2554,094
21290.13.48.0/2090.13.48.1 to 90.13.63.25490.13.63.2554,094
21390.13.64.0/2090.13.64.1 to 90.13.79.25490.13.79.2554,094
21490.13.80.0/2090.13.80.1 to 90.13.95.25490.13.95.2554,094
21590.13.96.0/2090.13.96.1 to 90.13.111.25490.13.111.2554,094
21690.13.112.0/2090.13.112.1 to 90.13.127.25490.13.127.2554,094
21790.13.128.0/2090.13.128.1 to 90.13.143.25490.13.143.2554,094
21890.13.144.0/2090.13.144.1 to 90.13.159.25490.13.159.2554,094
21990.13.160.0/2090.13.160.1 to 90.13.175.25490.13.175.2554,094
22090.13.176.0/2090.13.176.1 to 90.13.191.25490.13.191.2554,094
22190.13.192.0/2090.13.192.1 to 90.13.207.25490.13.207.2554,094
22290.13.208.0/2090.13.208.1 to 90.13.223.25490.13.223.2554,094
22390.13.224.0/2090.13.224.1 to 90.13.239.25490.13.239.2554,094
22490.13.240.0/2090.13.240.1 to 90.13.255.25490.13.255.2554,094
22590.14.0.0/2090.14.0.1 to 90.14.15.25490.14.15.2554,094
22690.14.16.0/2090.14.16.1 to 90.14.31.25490.14.31.2554,094
22790.14.32.0/2090.14.32.1 to 90.14.47.25490.14.47.2554,094
22890.14.48.0/2090.14.48.1 to 90.14.63.25490.14.63.2554,094
22990.14.64.0/2090.14.64.1 to 90.14.79.25490.14.79.2554,094
23090.14.80.0/2090.14.80.1 to 90.14.95.25490.14.95.2554,094
23190.14.96.0/2090.14.96.1 to 90.14.111.25490.14.111.2554,094
23290.14.112.0/2090.14.112.1 to 90.14.127.25490.14.127.2554,094
23390.14.128.0/2090.14.128.1 to 90.14.143.25490.14.143.2554,094
23490.14.144.0/2090.14.144.1 to 90.14.159.25490.14.159.2554,094
23590.14.160.0/2090.14.160.1 to 90.14.175.25490.14.175.2554,094
23690.14.176.0/2090.14.176.1 to 90.14.191.25490.14.191.2554,094
23790.14.192.0/2090.14.192.1 to 90.14.207.25490.14.207.2554,094
23890.14.208.0/2090.14.208.1 to 90.14.223.25490.14.223.2554,094
23990.14.224.0/2090.14.224.1 to 90.14.239.25490.14.239.2554,094
24090.14.240.0/2090.14.240.1 to 90.14.255.25490.14.255.2554,094
24190.15.0.0/2090.15.0.1 to 90.15.15.25490.15.15.2554,094
24290.15.16.0/2090.15.16.1 to 90.15.31.25490.15.31.2554,094
24390.15.32.0/2090.15.32.1 to 90.15.47.25490.15.47.2554,094
24490.15.48.0/2090.15.48.1 to 90.15.63.25490.15.63.2554,094
24590.15.64.0/2090.15.64.1 to 90.15.79.25490.15.79.2554,094
24690.15.80.0/2090.15.80.1 to 90.15.95.25490.15.95.2554,094
24790.15.96.0/2090.15.96.1 to 90.15.111.25490.15.111.2554,094
24890.15.112.0/2090.15.112.1 to 90.15.127.25490.15.127.2554,094
24990.15.128.0/2090.15.128.1 to 90.15.143.25490.15.143.2554,094
25090.15.144.0/2090.15.144.1 to 90.15.159.25490.15.159.2554,094
25190.15.160.0/2090.15.160.1 to 90.15.175.25490.15.175.2554,094
25290.15.176.0/2090.15.176.1 to 90.15.191.25490.15.191.2554,094
25390.15.192.0/2090.15.192.1 to 90.15.207.25490.15.207.2554,094
25490.15.208.0/2090.15.208.1 to 90.15.223.25490.15.223.2554,094
25590.15.224.0/2090.15.224.1 to 90.15.239.25490.15.239.2554,094
25690.15.240.0/2090.15.240.1 to 90.15.255.25490.15.255.2554,094

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.