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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.

Network92.128.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
92.128.0.0
Broadcast address
92.255.255.255
First usable
92.128.0.1
Last usable
92.255.255.254
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 5C800000 · Integer 1551892480 to 1560281087
Reverse DNS zones
128.92.in-addr.arpa
129.92.in-addr.arpa
130.92.in-addr.arpa
131.92.in-addr.arpa
132.92.in-addr.arpa
133.92.in-addr.arpa
134.92.in-addr.arpa
135.92.in-addr.arpa
136.92.in-addr.arpa
137.92.in-addr.arpa
138.92.in-addr.arpa
139.92.in-addr.arpa
140.92.in-addr.arpa
141.92.in-addr.arpa
142.92.in-addr.arpa
143.92.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
Address01011100.10000000.00000000.0000000092.128.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01011100.10000000.00000000.0000000092.128.0.0
Broadcast01011100.11111111.11111111.1111111192.255.255.255
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)

92.128.0.0/9 makes 2,048 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
192.128.0.0/2092.128.0.1 to 92.128.15.25492.128.15.2554,094
292.128.16.0/2092.128.16.1 to 92.128.31.25492.128.31.2554,094
392.128.32.0/2092.128.32.1 to 92.128.47.25492.128.47.2554,094
492.128.48.0/2092.128.48.1 to 92.128.63.25492.128.63.2554,094
592.128.64.0/2092.128.64.1 to 92.128.79.25492.128.79.2554,094
692.128.80.0/2092.128.80.1 to 92.128.95.25492.128.95.2554,094
792.128.96.0/2092.128.96.1 to 92.128.111.25492.128.111.2554,094
892.128.112.0/2092.128.112.1 to 92.128.127.25492.128.127.2554,094
992.128.128.0/2092.128.128.1 to 92.128.143.25492.128.143.2554,094
1092.128.144.0/2092.128.144.1 to 92.128.159.25492.128.159.2554,094
1192.128.160.0/2092.128.160.1 to 92.128.175.25492.128.175.2554,094
1292.128.176.0/2092.128.176.1 to 92.128.191.25492.128.191.2554,094
1392.128.192.0/2092.128.192.1 to 92.128.207.25492.128.207.2554,094
1492.128.208.0/2092.128.208.1 to 92.128.223.25492.128.223.2554,094
1592.128.224.0/2092.128.224.1 to 92.128.239.25492.128.239.2554,094
1692.128.240.0/2092.128.240.1 to 92.128.255.25492.128.255.2554,094
1792.129.0.0/2092.129.0.1 to 92.129.15.25492.129.15.2554,094
1892.129.16.0/2092.129.16.1 to 92.129.31.25492.129.31.2554,094
1992.129.32.0/2092.129.32.1 to 92.129.47.25492.129.47.2554,094
2092.129.48.0/2092.129.48.1 to 92.129.63.25492.129.63.2554,094
2192.129.64.0/2092.129.64.1 to 92.129.79.25492.129.79.2554,094
2292.129.80.0/2092.129.80.1 to 92.129.95.25492.129.95.2554,094
2392.129.96.0/2092.129.96.1 to 92.129.111.25492.129.111.2554,094
2492.129.112.0/2092.129.112.1 to 92.129.127.25492.129.127.2554,094
2592.129.128.0/2092.129.128.1 to 92.129.143.25492.129.143.2554,094
2692.129.144.0/2092.129.144.1 to 92.129.159.25492.129.159.2554,094
2792.129.160.0/2092.129.160.1 to 92.129.175.25492.129.175.2554,094
2892.129.176.0/2092.129.176.1 to 92.129.191.25492.129.191.2554,094
2992.129.192.0/2092.129.192.1 to 92.129.207.25492.129.207.2554,094
3092.129.208.0/2092.129.208.1 to 92.129.223.25492.129.223.2554,094
3192.129.224.0/2092.129.224.1 to 92.129.239.25492.129.239.2554,094
3292.129.240.0/2092.129.240.1 to 92.129.255.25492.129.255.2554,094
3392.130.0.0/2092.130.0.1 to 92.130.15.25492.130.15.2554,094
3492.130.16.0/2092.130.16.1 to 92.130.31.25492.130.31.2554,094
3592.130.32.0/2092.130.32.1 to 92.130.47.25492.130.47.2554,094
3692.130.48.0/2092.130.48.1 to 92.130.63.25492.130.63.2554,094
3792.130.64.0/2092.130.64.1 to 92.130.79.25492.130.79.2554,094
3892.130.80.0/2092.130.80.1 to 92.130.95.25492.130.95.2554,094
3992.130.96.0/2092.130.96.1 to 92.130.111.25492.130.111.2554,094
4092.130.112.0/2092.130.112.1 to 92.130.127.25492.130.127.2554,094
4192.130.128.0/2092.130.128.1 to 92.130.143.25492.130.143.2554,094
4292.130.144.0/2092.130.144.1 to 92.130.159.25492.130.159.2554,094
4392.130.160.0/2092.130.160.1 to 92.130.175.25492.130.175.2554,094
4492.130.176.0/2092.130.176.1 to 92.130.191.25492.130.191.2554,094
4592.130.192.0/2092.130.192.1 to 92.130.207.25492.130.207.2554,094
4692.130.208.0/2092.130.208.1 to 92.130.223.25492.130.223.2554,094
4792.130.224.0/2092.130.224.1 to 92.130.239.25492.130.239.2554,094
4892.130.240.0/2092.130.240.1 to 92.130.255.25492.130.255.2554,094
4992.131.0.0/2092.131.0.1 to 92.131.15.25492.131.15.2554,094
5092.131.16.0/2092.131.16.1 to 92.131.31.25492.131.31.2554,094
5192.131.32.0/2092.131.32.1 to 92.131.47.25492.131.47.2554,094
5292.131.48.0/2092.131.48.1 to 92.131.63.25492.131.63.2554,094
5392.131.64.0/2092.131.64.1 to 92.131.79.25492.131.79.2554,094
5492.131.80.0/2092.131.80.1 to 92.131.95.25492.131.95.2554,094
5592.131.96.0/2092.131.96.1 to 92.131.111.25492.131.111.2554,094
5692.131.112.0/2092.131.112.1 to 92.131.127.25492.131.127.2554,094
5792.131.128.0/2092.131.128.1 to 92.131.143.25492.131.143.2554,094
5892.131.144.0/2092.131.144.1 to 92.131.159.25492.131.159.2554,094
5992.131.160.0/2092.131.160.1 to 92.131.175.25492.131.175.2554,094
6092.131.176.0/2092.131.176.1 to 92.131.191.25492.131.191.2554,094
6192.131.192.0/2092.131.192.1 to 92.131.207.25492.131.207.2554,094
6292.131.208.0/2092.131.208.1 to 92.131.223.25492.131.223.2554,094
6392.131.224.0/2092.131.224.1 to 92.131.239.25492.131.239.2554,094
6492.131.240.0/2092.131.240.1 to 92.131.255.25492.131.255.2554,094
6592.132.0.0/2092.132.0.1 to 92.132.15.25492.132.15.2554,094
6692.132.16.0/2092.132.16.1 to 92.132.31.25492.132.31.2554,094
6792.132.32.0/2092.132.32.1 to 92.132.47.25492.132.47.2554,094
6892.132.48.0/2092.132.48.1 to 92.132.63.25492.132.63.2554,094
6992.132.64.0/2092.132.64.1 to 92.132.79.25492.132.79.2554,094
7092.132.80.0/2092.132.80.1 to 92.132.95.25492.132.95.2554,094
7192.132.96.0/2092.132.96.1 to 92.132.111.25492.132.111.2554,094
7292.132.112.0/2092.132.112.1 to 92.132.127.25492.132.127.2554,094
7392.132.128.0/2092.132.128.1 to 92.132.143.25492.132.143.2554,094
7492.132.144.0/2092.132.144.1 to 92.132.159.25492.132.159.2554,094
7592.132.160.0/2092.132.160.1 to 92.132.175.25492.132.175.2554,094
7692.132.176.0/2092.132.176.1 to 92.132.191.25492.132.191.2554,094
7792.132.192.0/2092.132.192.1 to 92.132.207.25492.132.207.2554,094
7892.132.208.0/2092.132.208.1 to 92.132.223.25492.132.223.2554,094
7992.132.224.0/2092.132.224.1 to 92.132.239.25492.132.239.2554,094
8092.132.240.0/2092.132.240.1 to 92.132.255.25492.132.255.2554,094
8192.133.0.0/2092.133.0.1 to 92.133.15.25492.133.15.2554,094
8292.133.16.0/2092.133.16.1 to 92.133.31.25492.133.31.2554,094
8392.133.32.0/2092.133.32.1 to 92.133.47.25492.133.47.2554,094
8492.133.48.0/2092.133.48.1 to 92.133.63.25492.133.63.2554,094
8592.133.64.0/2092.133.64.1 to 92.133.79.25492.133.79.2554,094
8692.133.80.0/2092.133.80.1 to 92.133.95.25492.133.95.2554,094
8792.133.96.0/2092.133.96.1 to 92.133.111.25492.133.111.2554,094
8892.133.112.0/2092.133.112.1 to 92.133.127.25492.133.127.2554,094
8992.133.128.0/2092.133.128.1 to 92.133.143.25492.133.143.2554,094
9092.133.144.0/2092.133.144.1 to 92.133.159.25492.133.159.2554,094
9192.133.160.0/2092.133.160.1 to 92.133.175.25492.133.175.2554,094
9292.133.176.0/2092.133.176.1 to 92.133.191.25492.133.191.2554,094
9392.133.192.0/2092.133.192.1 to 92.133.207.25492.133.207.2554,094
9492.133.208.0/2092.133.208.1 to 92.133.223.25492.133.223.2554,094
9592.133.224.0/2092.133.224.1 to 92.133.239.25492.133.239.2554,094
9692.133.240.0/2092.133.240.1 to 92.133.255.25492.133.255.2554,094
9792.134.0.0/2092.134.0.1 to 92.134.15.25492.134.15.2554,094
9892.134.16.0/2092.134.16.1 to 92.134.31.25492.134.31.2554,094
9992.134.32.0/2092.134.32.1 to 92.134.47.25492.134.47.2554,094
10092.134.48.0/2092.134.48.1 to 92.134.63.25492.134.63.2554,094
10192.134.64.0/2092.134.64.1 to 92.134.79.25492.134.79.2554,094
10292.134.80.0/2092.134.80.1 to 92.134.95.25492.134.95.2554,094
10392.134.96.0/2092.134.96.1 to 92.134.111.25492.134.111.2554,094
10492.134.112.0/2092.134.112.1 to 92.134.127.25492.134.127.2554,094
10592.134.128.0/2092.134.128.1 to 92.134.143.25492.134.143.2554,094
10692.134.144.0/2092.134.144.1 to 92.134.159.25492.134.159.2554,094
10792.134.160.0/2092.134.160.1 to 92.134.175.25492.134.175.2554,094
10892.134.176.0/2092.134.176.1 to 92.134.191.25492.134.191.2554,094
10992.134.192.0/2092.134.192.1 to 92.134.207.25492.134.207.2554,094
11092.134.208.0/2092.134.208.1 to 92.134.223.25492.134.223.2554,094
11192.134.224.0/2092.134.224.1 to 92.134.239.25492.134.239.2554,094
11292.134.240.0/2092.134.240.1 to 92.134.255.25492.134.255.2554,094
11392.135.0.0/2092.135.0.1 to 92.135.15.25492.135.15.2554,094
11492.135.16.0/2092.135.16.1 to 92.135.31.25492.135.31.2554,094
11592.135.32.0/2092.135.32.1 to 92.135.47.25492.135.47.2554,094
11692.135.48.0/2092.135.48.1 to 92.135.63.25492.135.63.2554,094
11792.135.64.0/2092.135.64.1 to 92.135.79.25492.135.79.2554,094
11892.135.80.0/2092.135.80.1 to 92.135.95.25492.135.95.2554,094
11992.135.96.0/2092.135.96.1 to 92.135.111.25492.135.111.2554,094
12092.135.112.0/2092.135.112.1 to 92.135.127.25492.135.127.2554,094
12192.135.128.0/2092.135.128.1 to 92.135.143.25492.135.143.2554,094
12292.135.144.0/2092.135.144.1 to 92.135.159.25492.135.159.2554,094
12392.135.160.0/2092.135.160.1 to 92.135.175.25492.135.175.2554,094
12492.135.176.0/2092.135.176.1 to 92.135.191.25492.135.191.2554,094
12592.135.192.0/2092.135.192.1 to 92.135.207.25492.135.207.2554,094
12692.135.208.0/2092.135.208.1 to 92.135.223.25492.135.223.2554,094
12792.135.224.0/2092.135.224.1 to 92.135.239.25492.135.239.2554,094
12892.135.240.0/2092.135.240.1 to 92.135.255.25492.135.255.2554,094
12992.136.0.0/2092.136.0.1 to 92.136.15.25492.136.15.2554,094
13092.136.16.0/2092.136.16.1 to 92.136.31.25492.136.31.2554,094
13192.136.32.0/2092.136.32.1 to 92.136.47.25492.136.47.2554,094
13292.136.48.0/2092.136.48.1 to 92.136.63.25492.136.63.2554,094
13392.136.64.0/2092.136.64.1 to 92.136.79.25492.136.79.2554,094
13492.136.80.0/2092.136.80.1 to 92.136.95.25492.136.95.2554,094
13592.136.96.0/2092.136.96.1 to 92.136.111.25492.136.111.2554,094
13692.136.112.0/2092.136.112.1 to 92.136.127.25492.136.127.2554,094
13792.136.128.0/2092.136.128.1 to 92.136.143.25492.136.143.2554,094
13892.136.144.0/2092.136.144.1 to 92.136.159.25492.136.159.2554,094
13992.136.160.0/2092.136.160.1 to 92.136.175.25492.136.175.2554,094
14092.136.176.0/2092.136.176.1 to 92.136.191.25492.136.191.2554,094
14192.136.192.0/2092.136.192.1 to 92.136.207.25492.136.207.2554,094
14292.136.208.0/2092.136.208.1 to 92.136.223.25492.136.223.2554,094
14392.136.224.0/2092.136.224.1 to 92.136.239.25492.136.239.2554,094
14492.136.240.0/2092.136.240.1 to 92.136.255.25492.136.255.2554,094
14592.137.0.0/2092.137.0.1 to 92.137.15.25492.137.15.2554,094
14692.137.16.0/2092.137.16.1 to 92.137.31.25492.137.31.2554,094
14792.137.32.0/2092.137.32.1 to 92.137.47.25492.137.47.2554,094
14892.137.48.0/2092.137.48.1 to 92.137.63.25492.137.63.2554,094
14992.137.64.0/2092.137.64.1 to 92.137.79.25492.137.79.2554,094
15092.137.80.0/2092.137.80.1 to 92.137.95.25492.137.95.2554,094
15192.137.96.0/2092.137.96.1 to 92.137.111.25492.137.111.2554,094
15292.137.112.0/2092.137.112.1 to 92.137.127.25492.137.127.2554,094
15392.137.128.0/2092.137.128.1 to 92.137.143.25492.137.143.2554,094
15492.137.144.0/2092.137.144.1 to 92.137.159.25492.137.159.2554,094
15592.137.160.0/2092.137.160.1 to 92.137.175.25492.137.175.2554,094
15692.137.176.0/2092.137.176.1 to 92.137.191.25492.137.191.2554,094
15792.137.192.0/2092.137.192.1 to 92.137.207.25492.137.207.2554,094
15892.137.208.0/2092.137.208.1 to 92.137.223.25492.137.223.2554,094
15992.137.224.0/2092.137.224.1 to 92.137.239.25492.137.239.2554,094
16092.137.240.0/2092.137.240.1 to 92.137.255.25492.137.255.2554,094
16192.138.0.0/2092.138.0.1 to 92.138.15.25492.138.15.2554,094
16292.138.16.0/2092.138.16.1 to 92.138.31.25492.138.31.2554,094
16392.138.32.0/2092.138.32.1 to 92.138.47.25492.138.47.2554,094
16492.138.48.0/2092.138.48.1 to 92.138.63.25492.138.63.2554,094
16592.138.64.0/2092.138.64.1 to 92.138.79.25492.138.79.2554,094
16692.138.80.0/2092.138.80.1 to 92.138.95.25492.138.95.2554,094
16792.138.96.0/2092.138.96.1 to 92.138.111.25492.138.111.2554,094
16892.138.112.0/2092.138.112.1 to 92.138.127.25492.138.127.2554,094
16992.138.128.0/2092.138.128.1 to 92.138.143.25492.138.143.2554,094
17092.138.144.0/2092.138.144.1 to 92.138.159.25492.138.159.2554,094
17192.138.160.0/2092.138.160.1 to 92.138.175.25492.138.175.2554,094
17292.138.176.0/2092.138.176.1 to 92.138.191.25492.138.191.2554,094
17392.138.192.0/2092.138.192.1 to 92.138.207.25492.138.207.2554,094
17492.138.208.0/2092.138.208.1 to 92.138.223.25492.138.223.2554,094
17592.138.224.0/2092.138.224.1 to 92.138.239.25492.138.239.2554,094
17692.138.240.0/2092.138.240.1 to 92.138.255.25492.138.255.2554,094
17792.139.0.0/2092.139.0.1 to 92.139.15.25492.139.15.2554,094
17892.139.16.0/2092.139.16.1 to 92.139.31.25492.139.31.2554,094
17992.139.32.0/2092.139.32.1 to 92.139.47.25492.139.47.2554,094
18092.139.48.0/2092.139.48.1 to 92.139.63.25492.139.63.2554,094
18192.139.64.0/2092.139.64.1 to 92.139.79.25492.139.79.2554,094
18292.139.80.0/2092.139.80.1 to 92.139.95.25492.139.95.2554,094
18392.139.96.0/2092.139.96.1 to 92.139.111.25492.139.111.2554,094
18492.139.112.0/2092.139.112.1 to 92.139.127.25492.139.127.2554,094
18592.139.128.0/2092.139.128.1 to 92.139.143.25492.139.143.2554,094
18692.139.144.0/2092.139.144.1 to 92.139.159.25492.139.159.2554,094
18792.139.160.0/2092.139.160.1 to 92.139.175.25492.139.175.2554,094
18892.139.176.0/2092.139.176.1 to 92.139.191.25492.139.191.2554,094
18992.139.192.0/2092.139.192.1 to 92.139.207.25492.139.207.2554,094
19092.139.208.0/2092.139.208.1 to 92.139.223.25492.139.223.2554,094
19192.139.224.0/2092.139.224.1 to 92.139.239.25492.139.239.2554,094
19292.139.240.0/2092.139.240.1 to 92.139.255.25492.139.255.2554,094
19392.140.0.0/2092.140.0.1 to 92.140.15.25492.140.15.2554,094
19492.140.16.0/2092.140.16.1 to 92.140.31.25492.140.31.2554,094
19592.140.32.0/2092.140.32.1 to 92.140.47.25492.140.47.2554,094
19692.140.48.0/2092.140.48.1 to 92.140.63.25492.140.63.2554,094
19792.140.64.0/2092.140.64.1 to 92.140.79.25492.140.79.2554,094
19892.140.80.0/2092.140.80.1 to 92.140.95.25492.140.95.2554,094
19992.140.96.0/2092.140.96.1 to 92.140.111.25492.140.111.2554,094
20092.140.112.0/2092.140.112.1 to 92.140.127.25492.140.127.2554,094
20192.140.128.0/2092.140.128.1 to 92.140.143.25492.140.143.2554,094
20292.140.144.0/2092.140.144.1 to 92.140.159.25492.140.159.2554,094
20392.140.160.0/2092.140.160.1 to 92.140.175.25492.140.175.2554,094
20492.140.176.0/2092.140.176.1 to 92.140.191.25492.140.191.2554,094
20592.140.192.0/2092.140.192.1 to 92.140.207.25492.140.207.2554,094
20692.140.208.0/2092.140.208.1 to 92.140.223.25492.140.223.2554,094
20792.140.224.0/2092.140.224.1 to 92.140.239.25492.140.239.2554,094
20892.140.240.0/2092.140.240.1 to 92.140.255.25492.140.255.2554,094
20992.141.0.0/2092.141.0.1 to 92.141.15.25492.141.15.2554,094
21092.141.16.0/2092.141.16.1 to 92.141.31.25492.141.31.2554,094
21192.141.32.0/2092.141.32.1 to 92.141.47.25492.141.47.2554,094
21292.141.48.0/2092.141.48.1 to 92.141.63.25492.141.63.2554,094
21392.141.64.0/2092.141.64.1 to 92.141.79.25492.141.79.2554,094
21492.141.80.0/2092.141.80.1 to 92.141.95.25492.141.95.2554,094
21592.141.96.0/2092.141.96.1 to 92.141.111.25492.141.111.2554,094
21692.141.112.0/2092.141.112.1 to 92.141.127.25492.141.127.2554,094
21792.141.128.0/2092.141.128.1 to 92.141.143.25492.141.143.2554,094
21892.141.144.0/2092.141.144.1 to 92.141.159.25492.141.159.2554,094
21992.141.160.0/2092.141.160.1 to 92.141.175.25492.141.175.2554,094
22092.141.176.0/2092.141.176.1 to 92.141.191.25492.141.191.2554,094
22192.141.192.0/2092.141.192.1 to 92.141.207.25492.141.207.2554,094
22292.141.208.0/2092.141.208.1 to 92.141.223.25492.141.223.2554,094
22392.141.224.0/2092.141.224.1 to 92.141.239.25492.141.239.2554,094
22492.141.240.0/2092.141.240.1 to 92.141.255.25492.141.255.2554,094
22592.142.0.0/2092.142.0.1 to 92.142.15.25492.142.15.2554,094
22692.142.16.0/2092.142.16.1 to 92.142.31.25492.142.31.2554,094
22792.142.32.0/2092.142.32.1 to 92.142.47.25492.142.47.2554,094
22892.142.48.0/2092.142.48.1 to 92.142.63.25492.142.63.2554,094
22992.142.64.0/2092.142.64.1 to 92.142.79.25492.142.79.2554,094
23092.142.80.0/2092.142.80.1 to 92.142.95.25492.142.95.2554,094
23192.142.96.0/2092.142.96.1 to 92.142.111.25492.142.111.2554,094
23292.142.112.0/2092.142.112.1 to 92.142.127.25492.142.127.2554,094
23392.142.128.0/2092.142.128.1 to 92.142.143.25492.142.143.2554,094
23492.142.144.0/2092.142.144.1 to 92.142.159.25492.142.159.2554,094
23592.142.160.0/2092.142.160.1 to 92.142.175.25492.142.175.2554,094
23692.142.176.0/2092.142.176.1 to 92.142.191.25492.142.191.2554,094
23792.142.192.0/2092.142.192.1 to 92.142.207.25492.142.207.2554,094
23892.142.208.0/2092.142.208.1 to 92.142.223.25492.142.223.2554,094
23992.142.224.0/2092.142.224.1 to 92.142.239.25492.142.239.2554,094
24092.142.240.0/2092.142.240.1 to 92.142.255.25492.142.255.2554,094
24192.143.0.0/2092.143.0.1 to 92.143.15.25492.143.15.2554,094
24292.143.16.0/2092.143.16.1 to 92.143.31.25492.143.31.2554,094
24392.143.32.0/2092.143.32.1 to 92.143.47.25492.143.47.2554,094
24492.143.48.0/2092.143.48.1 to 92.143.63.25492.143.63.2554,094
24592.143.64.0/2092.143.64.1 to 92.143.79.25492.143.79.2554,094
24692.143.80.0/2092.143.80.1 to 92.143.95.25492.143.95.2554,094
24792.143.96.0/2092.143.96.1 to 92.143.111.25492.143.111.2554,094
24892.143.112.0/2092.143.112.1 to 92.143.127.25492.143.127.2554,094
24992.143.128.0/2092.143.128.1 to 92.143.143.25492.143.143.2554,094
25092.143.144.0/2092.143.144.1 to 92.143.159.25492.143.159.2554,094
25192.143.160.0/2092.143.160.1 to 92.143.175.25492.143.175.2554,094
25292.143.176.0/2092.143.176.1 to 92.143.191.25492.143.191.2554,094
25392.143.192.0/2092.143.192.1 to 92.143.207.25492.143.207.2554,094
25492.143.208.0/2092.143.208.1 to 92.143.223.25492.143.223.2554,094
25592.143.224.0/2092.143.224.1 to 92.143.239.25492.143.239.2554,094
25692.143.240.0/2092.143.240.1 to 92.143.255.25492.143.255.2554,094

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.