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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.

Network92.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
92.0.0.0
Broadcast address
92.127.255.255
First usable
92.0.0.1
Last usable
92.127.255.254
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 5C000000 · Integer 1543503872 to 1551892479
Reverse DNS zones
0.92.in-addr.arpa
1.92.in-addr.arpa
2.92.in-addr.arpa
3.92.in-addr.arpa
4.92.in-addr.arpa
5.92.in-addr.arpa
6.92.in-addr.arpa
7.92.in-addr.arpa
8.92.in-addr.arpa
9.92.in-addr.arpa
10.92.in-addr.arpa
11.92.in-addr.arpa
12.92.in-addr.arpa
13.92.in-addr.arpa
14.92.in-addr.arpa
15.92.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
Address01011100.00000000.00000000.0000000092.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01011100.00000000.00000000.0000000092.0.0.0
Broadcast01011100.01111111.11111111.1111111192.127.255.255
Split into smaller subnets/19
/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)

92.0.0.0/9 makes 1,024 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
192.0.0.0/1992.0.0.1 to 92.0.31.25492.0.31.2558,190
292.0.32.0/1992.0.32.1 to 92.0.63.25492.0.63.2558,190
392.0.64.0/1992.0.64.1 to 92.0.95.25492.0.95.2558,190
492.0.96.0/1992.0.96.1 to 92.0.127.25492.0.127.2558,190
592.0.128.0/1992.0.128.1 to 92.0.159.25492.0.159.2558,190
692.0.160.0/1992.0.160.1 to 92.0.191.25492.0.191.2558,190
792.0.192.0/1992.0.192.1 to 92.0.223.25492.0.223.2558,190
892.0.224.0/1992.0.224.1 to 92.0.255.25492.0.255.2558,190
992.1.0.0/1992.1.0.1 to 92.1.31.25492.1.31.2558,190
1092.1.32.0/1992.1.32.1 to 92.1.63.25492.1.63.2558,190
1192.1.64.0/1992.1.64.1 to 92.1.95.25492.1.95.2558,190
1292.1.96.0/1992.1.96.1 to 92.1.127.25492.1.127.2558,190
1392.1.128.0/1992.1.128.1 to 92.1.159.25492.1.159.2558,190
1492.1.160.0/1992.1.160.1 to 92.1.191.25492.1.191.2558,190
1592.1.192.0/1992.1.192.1 to 92.1.223.25492.1.223.2558,190
1692.1.224.0/1992.1.224.1 to 92.1.255.25492.1.255.2558,190
1792.2.0.0/1992.2.0.1 to 92.2.31.25492.2.31.2558,190
1892.2.32.0/1992.2.32.1 to 92.2.63.25492.2.63.2558,190
1992.2.64.0/1992.2.64.1 to 92.2.95.25492.2.95.2558,190
2092.2.96.0/1992.2.96.1 to 92.2.127.25492.2.127.2558,190
2192.2.128.0/1992.2.128.1 to 92.2.159.25492.2.159.2558,190
2292.2.160.0/1992.2.160.1 to 92.2.191.25492.2.191.2558,190
2392.2.192.0/1992.2.192.1 to 92.2.223.25492.2.223.2558,190
2492.2.224.0/1992.2.224.1 to 92.2.255.25492.2.255.2558,190
2592.3.0.0/1992.3.0.1 to 92.3.31.25492.3.31.2558,190
2692.3.32.0/1992.3.32.1 to 92.3.63.25492.3.63.2558,190
2792.3.64.0/1992.3.64.1 to 92.3.95.25492.3.95.2558,190
2892.3.96.0/1992.3.96.1 to 92.3.127.25492.3.127.2558,190
2992.3.128.0/1992.3.128.1 to 92.3.159.25492.3.159.2558,190
3092.3.160.0/1992.3.160.1 to 92.3.191.25492.3.191.2558,190
3192.3.192.0/1992.3.192.1 to 92.3.223.25492.3.223.2558,190
3292.3.224.0/1992.3.224.1 to 92.3.255.25492.3.255.2558,190
3392.4.0.0/1992.4.0.1 to 92.4.31.25492.4.31.2558,190
3492.4.32.0/1992.4.32.1 to 92.4.63.25492.4.63.2558,190
3592.4.64.0/1992.4.64.1 to 92.4.95.25492.4.95.2558,190
3692.4.96.0/1992.4.96.1 to 92.4.127.25492.4.127.2558,190
3792.4.128.0/1992.4.128.1 to 92.4.159.25492.4.159.2558,190
3892.4.160.0/1992.4.160.1 to 92.4.191.25492.4.191.2558,190
3992.4.192.0/1992.4.192.1 to 92.4.223.25492.4.223.2558,190
4092.4.224.0/1992.4.224.1 to 92.4.255.25492.4.255.2558,190
4192.5.0.0/1992.5.0.1 to 92.5.31.25492.5.31.2558,190
4292.5.32.0/1992.5.32.1 to 92.5.63.25492.5.63.2558,190
4392.5.64.0/1992.5.64.1 to 92.5.95.25492.5.95.2558,190
4492.5.96.0/1992.5.96.1 to 92.5.127.25492.5.127.2558,190
4592.5.128.0/1992.5.128.1 to 92.5.159.25492.5.159.2558,190
4692.5.160.0/1992.5.160.1 to 92.5.191.25492.5.191.2558,190
4792.5.192.0/1992.5.192.1 to 92.5.223.25492.5.223.2558,190
4892.5.224.0/1992.5.224.1 to 92.5.255.25492.5.255.2558,190
4992.6.0.0/1992.6.0.1 to 92.6.31.25492.6.31.2558,190
5092.6.32.0/1992.6.32.1 to 92.6.63.25492.6.63.2558,190
5192.6.64.0/1992.6.64.1 to 92.6.95.25492.6.95.2558,190
5292.6.96.0/1992.6.96.1 to 92.6.127.25492.6.127.2558,190
5392.6.128.0/1992.6.128.1 to 92.6.159.25492.6.159.2558,190
5492.6.160.0/1992.6.160.1 to 92.6.191.25492.6.191.2558,190
5592.6.192.0/1992.6.192.1 to 92.6.223.25492.6.223.2558,190
5692.6.224.0/1992.6.224.1 to 92.6.255.25492.6.255.2558,190
5792.7.0.0/1992.7.0.1 to 92.7.31.25492.7.31.2558,190
5892.7.32.0/1992.7.32.1 to 92.7.63.25492.7.63.2558,190
5992.7.64.0/1992.7.64.1 to 92.7.95.25492.7.95.2558,190
6092.7.96.0/1992.7.96.1 to 92.7.127.25492.7.127.2558,190
6192.7.128.0/1992.7.128.1 to 92.7.159.25492.7.159.2558,190
6292.7.160.0/1992.7.160.1 to 92.7.191.25492.7.191.2558,190
6392.7.192.0/1992.7.192.1 to 92.7.223.25492.7.223.2558,190
6492.7.224.0/1992.7.224.1 to 92.7.255.25492.7.255.2558,190
6592.8.0.0/1992.8.0.1 to 92.8.31.25492.8.31.2558,190
6692.8.32.0/1992.8.32.1 to 92.8.63.25492.8.63.2558,190
6792.8.64.0/1992.8.64.1 to 92.8.95.25492.8.95.2558,190
6892.8.96.0/1992.8.96.1 to 92.8.127.25492.8.127.2558,190
6992.8.128.0/1992.8.128.1 to 92.8.159.25492.8.159.2558,190
7092.8.160.0/1992.8.160.1 to 92.8.191.25492.8.191.2558,190
7192.8.192.0/1992.8.192.1 to 92.8.223.25492.8.223.2558,190
7292.8.224.0/1992.8.224.1 to 92.8.255.25492.8.255.2558,190
7392.9.0.0/1992.9.0.1 to 92.9.31.25492.9.31.2558,190
7492.9.32.0/1992.9.32.1 to 92.9.63.25492.9.63.2558,190
7592.9.64.0/1992.9.64.1 to 92.9.95.25492.9.95.2558,190
7692.9.96.0/1992.9.96.1 to 92.9.127.25492.9.127.2558,190
7792.9.128.0/1992.9.128.1 to 92.9.159.25492.9.159.2558,190
7892.9.160.0/1992.9.160.1 to 92.9.191.25492.9.191.2558,190
7992.9.192.0/1992.9.192.1 to 92.9.223.25492.9.223.2558,190
8092.9.224.0/1992.9.224.1 to 92.9.255.25492.9.255.2558,190
8192.10.0.0/1992.10.0.1 to 92.10.31.25492.10.31.2558,190
8292.10.32.0/1992.10.32.1 to 92.10.63.25492.10.63.2558,190
8392.10.64.0/1992.10.64.1 to 92.10.95.25492.10.95.2558,190
8492.10.96.0/1992.10.96.1 to 92.10.127.25492.10.127.2558,190
8592.10.128.0/1992.10.128.1 to 92.10.159.25492.10.159.2558,190
8692.10.160.0/1992.10.160.1 to 92.10.191.25492.10.191.2558,190
8792.10.192.0/1992.10.192.1 to 92.10.223.25492.10.223.2558,190
8892.10.224.0/1992.10.224.1 to 92.10.255.25492.10.255.2558,190
8992.11.0.0/1992.11.0.1 to 92.11.31.25492.11.31.2558,190
9092.11.32.0/1992.11.32.1 to 92.11.63.25492.11.63.2558,190
9192.11.64.0/1992.11.64.1 to 92.11.95.25492.11.95.2558,190
9292.11.96.0/1992.11.96.1 to 92.11.127.25492.11.127.2558,190
9392.11.128.0/1992.11.128.1 to 92.11.159.25492.11.159.2558,190
9492.11.160.0/1992.11.160.1 to 92.11.191.25492.11.191.2558,190
9592.11.192.0/1992.11.192.1 to 92.11.223.25492.11.223.2558,190
9692.11.224.0/1992.11.224.1 to 92.11.255.25492.11.255.2558,190
9792.12.0.0/1992.12.0.1 to 92.12.31.25492.12.31.2558,190
9892.12.32.0/1992.12.32.1 to 92.12.63.25492.12.63.2558,190
9992.12.64.0/1992.12.64.1 to 92.12.95.25492.12.95.2558,190
10092.12.96.0/1992.12.96.1 to 92.12.127.25492.12.127.2558,190
10192.12.128.0/1992.12.128.1 to 92.12.159.25492.12.159.2558,190
10292.12.160.0/1992.12.160.1 to 92.12.191.25492.12.191.2558,190
10392.12.192.0/1992.12.192.1 to 92.12.223.25492.12.223.2558,190
10492.12.224.0/1992.12.224.1 to 92.12.255.25492.12.255.2558,190
10592.13.0.0/1992.13.0.1 to 92.13.31.25492.13.31.2558,190
10692.13.32.0/1992.13.32.1 to 92.13.63.25492.13.63.2558,190
10792.13.64.0/1992.13.64.1 to 92.13.95.25492.13.95.2558,190
10892.13.96.0/1992.13.96.1 to 92.13.127.25492.13.127.2558,190
10992.13.128.0/1992.13.128.1 to 92.13.159.25492.13.159.2558,190
11092.13.160.0/1992.13.160.1 to 92.13.191.25492.13.191.2558,190
11192.13.192.0/1992.13.192.1 to 92.13.223.25492.13.223.2558,190
11292.13.224.0/1992.13.224.1 to 92.13.255.25492.13.255.2558,190
11392.14.0.0/1992.14.0.1 to 92.14.31.25492.14.31.2558,190
11492.14.32.0/1992.14.32.1 to 92.14.63.25492.14.63.2558,190
11592.14.64.0/1992.14.64.1 to 92.14.95.25492.14.95.2558,190
11692.14.96.0/1992.14.96.1 to 92.14.127.25492.14.127.2558,190
11792.14.128.0/1992.14.128.1 to 92.14.159.25492.14.159.2558,190
11892.14.160.0/1992.14.160.1 to 92.14.191.25492.14.191.2558,190
11992.14.192.0/1992.14.192.1 to 92.14.223.25492.14.223.2558,190
12092.14.224.0/1992.14.224.1 to 92.14.255.25492.14.255.2558,190
12192.15.0.0/1992.15.0.1 to 92.15.31.25492.15.31.2558,190
12292.15.32.0/1992.15.32.1 to 92.15.63.25492.15.63.2558,190
12392.15.64.0/1992.15.64.1 to 92.15.95.25492.15.95.2558,190
12492.15.96.0/1992.15.96.1 to 92.15.127.25492.15.127.2558,190
12592.15.128.0/1992.15.128.1 to 92.15.159.25492.15.159.2558,190
12692.15.160.0/1992.15.160.1 to 92.15.191.25492.15.191.2558,190
12792.15.192.0/1992.15.192.1 to 92.15.223.25492.15.223.2558,190
12892.15.224.0/1992.15.224.1 to 92.15.255.25492.15.255.2558,190
12992.16.0.0/1992.16.0.1 to 92.16.31.25492.16.31.2558,190
13092.16.32.0/1992.16.32.1 to 92.16.63.25492.16.63.2558,190
13192.16.64.0/1992.16.64.1 to 92.16.95.25492.16.95.2558,190
13292.16.96.0/1992.16.96.1 to 92.16.127.25492.16.127.2558,190
13392.16.128.0/1992.16.128.1 to 92.16.159.25492.16.159.2558,190
13492.16.160.0/1992.16.160.1 to 92.16.191.25492.16.191.2558,190
13592.16.192.0/1992.16.192.1 to 92.16.223.25492.16.223.2558,190
13692.16.224.0/1992.16.224.1 to 92.16.255.25492.16.255.2558,190
13792.17.0.0/1992.17.0.1 to 92.17.31.25492.17.31.2558,190
13892.17.32.0/1992.17.32.1 to 92.17.63.25492.17.63.2558,190
13992.17.64.0/1992.17.64.1 to 92.17.95.25492.17.95.2558,190
14092.17.96.0/1992.17.96.1 to 92.17.127.25492.17.127.2558,190
14192.17.128.0/1992.17.128.1 to 92.17.159.25492.17.159.2558,190
14292.17.160.0/1992.17.160.1 to 92.17.191.25492.17.191.2558,190
14392.17.192.0/1992.17.192.1 to 92.17.223.25492.17.223.2558,190
14492.17.224.0/1992.17.224.1 to 92.17.255.25492.17.255.2558,190
14592.18.0.0/1992.18.0.1 to 92.18.31.25492.18.31.2558,190
14692.18.32.0/1992.18.32.1 to 92.18.63.25492.18.63.2558,190
14792.18.64.0/1992.18.64.1 to 92.18.95.25492.18.95.2558,190
14892.18.96.0/1992.18.96.1 to 92.18.127.25492.18.127.2558,190
14992.18.128.0/1992.18.128.1 to 92.18.159.25492.18.159.2558,190
15092.18.160.0/1992.18.160.1 to 92.18.191.25492.18.191.2558,190
15192.18.192.0/1992.18.192.1 to 92.18.223.25492.18.223.2558,190
15292.18.224.0/1992.18.224.1 to 92.18.255.25492.18.255.2558,190
15392.19.0.0/1992.19.0.1 to 92.19.31.25492.19.31.2558,190
15492.19.32.0/1992.19.32.1 to 92.19.63.25492.19.63.2558,190
15592.19.64.0/1992.19.64.1 to 92.19.95.25492.19.95.2558,190
15692.19.96.0/1992.19.96.1 to 92.19.127.25492.19.127.2558,190
15792.19.128.0/1992.19.128.1 to 92.19.159.25492.19.159.2558,190
15892.19.160.0/1992.19.160.1 to 92.19.191.25492.19.191.2558,190
15992.19.192.0/1992.19.192.1 to 92.19.223.25492.19.223.2558,190
16092.19.224.0/1992.19.224.1 to 92.19.255.25492.19.255.2558,190
16192.20.0.0/1992.20.0.1 to 92.20.31.25492.20.31.2558,190
16292.20.32.0/1992.20.32.1 to 92.20.63.25492.20.63.2558,190
16392.20.64.0/1992.20.64.1 to 92.20.95.25492.20.95.2558,190
16492.20.96.0/1992.20.96.1 to 92.20.127.25492.20.127.2558,190
16592.20.128.0/1992.20.128.1 to 92.20.159.25492.20.159.2558,190
16692.20.160.0/1992.20.160.1 to 92.20.191.25492.20.191.2558,190
16792.20.192.0/1992.20.192.1 to 92.20.223.25492.20.223.2558,190
16892.20.224.0/1992.20.224.1 to 92.20.255.25492.20.255.2558,190
16992.21.0.0/1992.21.0.1 to 92.21.31.25492.21.31.2558,190
17092.21.32.0/1992.21.32.1 to 92.21.63.25492.21.63.2558,190
17192.21.64.0/1992.21.64.1 to 92.21.95.25492.21.95.2558,190
17292.21.96.0/1992.21.96.1 to 92.21.127.25492.21.127.2558,190
17392.21.128.0/1992.21.128.1 to 92.21.159.25492.21.159.2558,190
17492.21.160.0/1992.21.160.1 to 92.21.191.25492.21.191.2558,190
17592.21.192.0/1992.21.192.1 to 92.21.223.25492.21.223.2558,190
17692.21.224.0/1992.21.224.1 to 92.21.255.25492.21.255.2558,190
17792.22.0.0/1992.22.0.1 to 92.22.31.25492.22.31.2558,190
17892.22.32.0/1992.22.32.1 to 92.22.63.25492.22.63.2558,190
17992.22.64.0/1992.22.64.1 to 92.22.95.25492.22.95.2558,190
18092.22.96.0/1992.22.96.1 to 92.22.127.25492.22.127.2558,190
18192.22.128.0/1992.22.128.1 to 92.22.159.25492.22.159.2558,190
18292.22.160.0/1992.22.160.1 to 92.22.191.25492.22.191.2558,190
18392.22.192.0/1992.22.192.1 to 92.22.223.25492.22.223.2558,190
18492.22.224.0/1992.22.224.1 to 92.22.255.25492.22.255.2558,190
18592.23.0.0/1992.23.0.1 to 92.23.31.25492.23.31.2558,190
18692.23.32.0/1992.23.32.1 to 92.23.63.25492.23.63.2558,190
18792.23.64.0/1992.23.64.1 to 92.23.95.25492.23.95.2558,190
18892.23.96.0/1992.23.96.1 to 92.23.127.25492.23.127.2558,190
18992.23.128.0/1992.23.128.1 to 92.23.159.25492.23.159.2558,190
19092.23.160.0/1992.23.160.1 to 92.23.191.25492.23.191.2558,190
19192.23.192.0/1992.23.192.1 to 92.23.223.25492.23.223.2558,190
19292.23.224.0/1992.23.224.1 to 92.23.255.25492.23.255.2558,190
19392.24.0.0/1992.24.0.1 to 92.24.31.25492.24.31.2558,190
19492.24.32.0/1992.24.32.1 to 92.24.63.25492.24.63.2558,190
19592.24.64.0/1992.24.64.1 to 92.24.95.25492.24.95.2558,190
19692.24.96.0/1992.24.96.1 to 92.24.127.25492.24.127.2558,190
19792.24.128.0/1992.24.128.1 to 92.24.159.25492.24.159.2558,190
19892.24.160.0/1992.24.160.1 to 92.24.191.25492.24.191.2558,190
19992.24.192.0/1992.24.192.1 to 92.24.223.25492.24.223.2558,190
20092.24.224.0/1992.24.224.1 to 92.24.255.25492.24.255.2558,190
20192.25.0.0/1992.25.0.1 to 92.25.31.25492.25.31.2558,190
20292.25.32.0/1992.25.32.1 to 92.25.63.25492.25.63.2558,190
20392.25.64.0/1992.25.64.1 to 92.25.95.25492.25.95.2558,190
20492.25.96.0/1992.25.96.1 to 92.25.127.25492.25.127.2558,190
20592.25.128.0/1992.25.128.1 to 92.25.159.25492.25.159.2558,190
20692.25.160.0/1992.25.160.1 to 92.25.191.25492.25.191.2558,190
20792.25.192.0/1992.25.192.1 to 92.25.223.25492.25.223.2558,190
20892.25.224.0/1992.25.224.1 to 92.25.255.25492.25.255.2558,190
20992.26.0.0/1992.26.0.1 to 92.26.31.25492.26.31.2558,190
21092.26.32.0/1992.26.32.1 to 92.26.63.25492.26.63.2558,190
21192.26.64.0/1992.26.64.1 to 92.26.95.25492.26.95.2558,190
21292.26.96.0/1992.26.96.1 to 92.26.127.25492.26.127.2558,190
21392.26.128.0/1992.26.128.1 to 92.26.159.25492.26.159.2558,190
21492.26.160.0/1992.26.160.1 to 92.26.191.25492.26.191.2558,190
21592.26.192.0/1992.26.192.1 to 92.26.223.25492.26.223.2558,190
21692.26.224.0/1992.26.224.1 to 92.26.255.25492.26.255.2558,190
21792.27.0.0/1992.27.0.1 to 92.27.31.25492.27.31.2558,190
21892.27.32.0/1992.27.32.1 to 92.27.63.25492.27.63.2558,190
21992.27.64.0/1992.27.64.1 to 92.27.95.25492.27.95.2558,190
22092.27.96.0/1992.27.96.1 to 92.27.127.25492.27.127.2558,190
22192.27.128.0/1992.27.128.1 to 92.27.159.25492.27.159.2558,190
22292.27.160.0/1992.27.160.1 to 92.27.191.25492.27.191.2558,190
22392.27.192.0/1992.27.192.1 to 92.27.223.25492.27.223.2558,190
22492.27.224.0/1992.27.224.1 to 92.27.255.25492.27.255.2558,190
22592.28.0.0/1992.28.0.1 to 92.28.31.25492.28.31.2558,190
22692.28.32.0/1992.28.32.1 to 92.28.63.25492.28.63.2558,190
22792.28.64.0/1992.28.64.1 to 92.28.95.25492.28.95.2558,190
22892.28.96.0/1992.28.96.1 to 92.28.127.25492.28.127.2558,190
22992.28.128.0/1992.28.128.1 to 92.28.159.25492.28.159.2558,190
23092.28.160.0/1992.28.160.1 to 92.28.191.25492.28.191.2558,190
23192.28.192.0/1992.28.192.1 to 92.28.223.25492.28.223.2558,190
23292.28.224.0/1992.28.224.1 to 92.28.255.25492.28.255.2558,190
23392.29.0.0/1992.29.0.1 to 92.29.31.25492.29.31.2558,190
23492.29.32.0/1992.29.32.1 to 92.29.63.25492.29.63.2558,190
23592.29.64.0/1992.29.64.1 to 92.29.95.25492.29.95.2558,190
23692.29.96.0/1992.29.96.1 to 92.29.127.25492.29.127.2558,190
23792.29.128.0/1992.29.128.1 to 92.29.159.25492.29.159.2558,190
23892.29.160.0/1992.29.160.1 to 92.29.191.25492.29.191.2558,190
23992.29.192.0/1992.29.192.1 to 92.29.223.25492.29.223.2558,190
24092.29.224.0/1992.29.224.1 to 92.29.255.25492.29.255.2558,190
24192.30.0.0/1992.30.0.1 to 92.30.31.25492.30.31.2558,190
24292.30.32.0/1992.30.32.1 to 92.30.63.25492.30.63.2558,190
24392.30.64.0/1992.30.64.1 to 92.30.95.25492.30.95.2558,190
24492.30.96.0/1992.30.96.1 to 92.30.127.25492.30.127.2558,190
24592.30.128.0/1992.30.128.1 to 92.30.159.25492.30.159.2558,190
24692.30.160.0/1992.30.160.1 to 92.30.191.25492.30.191.2558,190
24792.30.192.0/1992.30.192.1 to 92.30.223.25492.30.223.2558,190
24892.30.224.0/1992.30.224.1 to 92.30.255.25492.30.255.2558,190
24992.31.0.0/1992.31.0.1 to 92.31.31.25492.31.31.2558,190
25092.31.32.0/1992.31.32.1 to 92.31.63.25492.31.63.2558,190
25192.31.64.0/1992.31.64.1 to 92.31.95.25492.31.95.2558,190
25292.31.96.0/1992.31.96.1 to 92.31.127.25492.31.127.2558,190
25392.31.128.0/1992.31.128.1 to 92.31.159.25492.31.159.2558,190
25492.31.160.0/1992.31.160.1 to 92.31.191.25492.31.191.2558,190
25592.31.192.0/1992.31.192.1 to 92.31.223.25492.31.223.2558,190
25692.31.224.0/1992.31.224.1 to 92.31.255.25492.31.255.2558,190

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.