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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.

Network60.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
60.0.0.0
Broadcast address
60.127.255.255
First usable
60.0.0.1
Last usable
60.127.255.254
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 3C000000 · Integer 1006632960 to 1015021567
Reverse DNS zones
0.60.in-addr.arpa
1.60.in-addr.arpa
2.60.in-addr.arpa
3.60.in-addr.arpa
4.60.in-addr.arpa
5.60.in-addr.arpa
6.60.in-addr.arpa
7.60.in-addr.arpa
8.60.in-addr.arpa
9.60.in-addr.arpa
10.60.in-addr.arpa
11.60.in-addr.arpa
12.60.in-addr.arpa
13.60.in-addr.arpa
14.60.in-addr.arpa
15.60.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
Address00111100.00000000.00000000.0000000060.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network00111100.00000000.00000000.0000000060.0.0.0
Broadcast00111100.01111111.11111111.1111111160.127.255.255
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)

60.0.0.0/9 makes 2,048 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
160.0.0.0/2060.0.0.1 to 60.0.15.25460.0.15.2554,094
260.0.16.0/2060.0.16.1 to 60.0.31.25460.0.31.2554,094
360.0.32.0/2060.0.32.1 to 60.0.47.25460.0.47.2554,094
460.0.48.0/2060.0.48.1 to 60.0.63.25460.0.63.2554,094
560.0.64.0/2060.0.64.1 to 60.0.79.25460.0.79.2554,094
660.0.80.0/2060.0.80.1 to 60.0.95.25460.0.95.2554,094
760.0.96.0/2060.0.96.1 to 60.0.111.25460.0.111.2554,094
860.0.112.0/2060.0.112.1 to 60.0.127.25460.0.127.2554,094
960.0.128.0/2060.0.128.1 to 60.0.143.25460.0.143.2554,094
1060.0.144.0/2060.0.144.1 to 60.0.159.25460.0.159.2554,094
1160.0.160.0/2060.0.160.1 to 60.0.175.25460.0.175.2554,094
1260.0.176.0/2060.0.176.1 to 60.0.191.25460.0.191.2554,094
1360.0.192.0/2060.0.192.1 to 60.0.207.25460.0.207.2554,094
1460.0.208.0/2060.0.208.1 to 60.0.223.25460.0.223.2554,094
1560.0.224.0/2060.0.224.1 to 60.0.239.25460.0.239.2554,094
1660.0.240.0/2060.0.240.1 to 60.0.255.25460.0.255.2554,094
1760.1.0.0/2060.1.0.1 to 60.1.15.25460.1.15.2554,094
1860.1.16.0/2060.1.16.1 to 60.1.31.25460.1.31.2554,094
1960.1.32.0/2060.1.32.1 to 60.1.47.25460.1.47.2554,094
2060.1.48.0/2060.1.48.1 to 60.1.63.25460.1.63.2554,094
2160.1.64.0/2060.1.64.1 to 60.1.79.25460.1.79.2554,094
2260.1.80.0/2060.1.80.1 to 60.1.95.25460.1.95.2554,094
2360.1.96.0/2060.1.96.1 to 60.1.111.25460.1.111.2554,094
2460.1.112.0/2060.1.112.1 to 60.1.127.25460.1.127.2554,094
2560.1.128.0/2060.1.128.1 to 60.1.143.25460.1.143.2554,094
2660.1.144.0/2060.1.144.1 to 60.1.159.25460.1.159.2554,094
2760.1.160.0/2060.1.160.1 to 60.1.175.25460.1.175.2554,094
2860.1.176.0/2060.1.176.1 to 60.1.191.25460.1.191.2554,094
2960.1.192.0/2060.1.192.1 to 60.1.207.25460.1.207.2554,094
3060.1.208.0/2060.1.208.1 to 60.1.223.25460.1.223.2554,094
3160.1.224.0/2060.1.224.1 to 60.1.239.25460.1.239.2554,094
3260.1.240.0/2060.1.240.1 to 60.1.255.25460.1.255.2554,094
3360.2.0.0/2060.2.0.1 to 60.2.15.25460.2.15.2554,094
3460.2.16.0/2060.2.16.1 to 60.2.31.25460.2.31.2554,094
3560.2.32.0/2060.2.32.1 to 60.2.47.25460.2.47.2554,094
3660.2.48.0/2060.2.48.1 to 60.2.63.25460.2.63.2554,094
3760.2.64.0/2060.2.64.1 to 60.2.79.25460.2.79.2554,094
3860.2.80.0/2060.2.80.1 to 60.2.95.25460.2.95.2554,094
3960.2.96.0/2060.2.96.1 to 60.2.111.25460.2.111.2554,094
4060.2.112.0/2060.2.112.1 to 60.2.127.25460.2.127.2554,094
4160.2.128.0/2060.2.128.1 to 60.2.143.25460.2.143.2554,094
4260.2.144.0/2060.2.144.1 to 60.2.159.25460.2.159.2554,094
4360.2.160.0/2060.2.160.1 to 60.2.175.25460.2.175.2554,094
4460.2.176.0/2060.2.176.1 to 60.2.191.25460.2.191.2554,094
4560.2.192.0/2060.2.192.1 to 60.2.207.25460.2.207.2554,094
4660.2.208.0/2060.2.208.1 to 60.2.223.25460.2.223.2554,094
4760.2.224.0/2060.2.224.1 to 60.2.239.25460.2.239.2554,094
4860.2.240.0/2060.2.240.1 to 60.2.255.25460.2.255.2554,094
4960.3.0.0/2060.3.0.1 to 60.3.15.25460.3.15.2554,094
5060.3.16.0/2060.3.16.1 to 60.3.31.25460.3.31.2554,094
5160.3.32.0/2060.3.32.1 to 60.3.47.25460.3.47.2554,094
5260.3.48.0/2060.3.48.1 to 60.3.63.25460.3.63.2554,094
5360.3.64.0/2060.3.64.1 to 60.3.79.25460.3.79.2554,094
5460.3.80.0/2060.3.80.1 to 60.3.95.25460.3.95.2554,094
5560.3.96.0/2060.3.96.1 to 60.3.111.25460.3.111.2554,094
5660.3.112.0/2060.3.112.1 to 60.3.127.25460.3.127.2554,094
5760.3.128.0/2060.3.128.1 to 60.3.143.25460.3.143.2554,094
5860.3.144.0/2060.3.144.1 to 60.3.159.25460.3.159.2554,094
5960.3.160.0/2060.3.160.1 to 60.3.175.25460.3.175.2554,094
6060.3.176.0/2060.3.176.1 to 60.3.191.25460.3.191.2554,094
6160.3.192.0/2060.3.192.1 to 60.3.207.25460.3.207.2554,094
6260.3.208.0/2060.3.208.1 to 60.3.223.25460.3.223.2554,094
6360.3.224.0/2060.3.224.1 to 60.3.239.25460.3.239.2554,094
6460.3.240.0/2060.3.240.1 to 60.3.255.25460.3.255.2554,094
6560.4.0.0/2060.4.0.1 to 60.4.15.25460.4.15.2554,094
6660.4.16.0/2060.4.16.1 to 60.4.31.25460.4.31.2554,094
6760.4.32.0/2060.4.32.1 to 60.4.47.25460.4.47.2554,094
6860.4.48.0/2060.4.48.1 to 60.4.63.25460.4.63.2554,094
6960.4.64.0/2060.4.64.1 to 60.4.79.25460.4.79.2554,094
7060.4.80.0/2060.4.80.1 to 60.4.95.25460.4.95.2554,094
7160.4.96.0/2060.4.96.1 to 60.4.111.25460.4.111.2554,094
7260.4.112.0/2060.4.112.1 to 60.4.127.25460.4.127.2554,094
7360.4.128.0/2060.4.128.1 to 60.4.143.25460.4.143.2554,094
7460.4.144.0/2060.4.144.1 to 60.4.159.25460.4.159.2554,094
7560.4.160.0/2060.4.160.1 to 60.4.175.25460.4.175.2554,094
7660.4.176.0/2060.4.176.1 to 60.4.191.25460.4.191.2554,094
7760.4.192.0/2060.4.192.1 to 60.4.207.25460.4.207.2554,094
7860.4.208.0/2060.4.208.1 to 60.4.223.25460.4.223.2554,094
7960.4.224.0/2060.4.224.1 to 60.4.239.25460.4.239.2554,094
8060.4.240.0/2060.4.240.1 to 60.4.255.25460.4.255.2554,094
8160.5.0.0/2060.5.0.1 to 60.5.15.25460.5.15.2554,094
8260.5.16.0/2060.5.16.1 to 60.5.31.25460.5.31.2554,094
8360.5.32.0/2060.5.32.1 to 60.5.47.25460.5.47.2554,094
8460.5.48.0/2060.5.48.1 to 60.5.63.25460.5.63.2554,094
8560.5.64.0/2060.5.64.1 to 60.5.79.25460.5.79.2554,094
8660.5.80.0/2060.5.80.1 to 60.5.95.25460.5.95.2554,094
8760.5.96.0/2060.5.96.1 to 60.5.111.25460.5.111.2554,094
8860.5.112.0/2060.5.112.1 to 60.5.127.25460.5.127.2554,094
8960.5.128.0/2060.5.128.1 to 60.5.143.25460.5.143.2554,094
9060.5.144.0/2060.5.144.1 to 60.5.159.25460.5.159.2554,094
9160.5.160.0/2060.5.160.1 to 60.5.175.25460.5.175.2554,094
9260.5.176.0/2060.5.176.1 to 60.5.191.25460.5.191.2554,094
9360.5.192.0/2060.5.192.1 to 60.5.207.25460.5.207.2554,094
9460.5.208.0/2060.5.208.1 to 60.5.223.25460.5.223.2554,094
9560.5.224.0/2060.5.224.1 to 60.5.239.25460.5.239.2554,094
9660.5.240.0/2060.5.240.1 to 60.5.255.25460.5.255.2554,094
9760.6.0.0/2060.6.0.1 to 60.6.15.25460.6.15.2554,094
9860.6.16.0/2060.6.16.1 to 60.6.31.25460.6.31.2554,094
9960.6.32.0/2060.6.32.1 to 60.6.47.25460.6.47.2554,094
10060.6.48.0/2060.6.48.1 to 60.6.63.25460.6.63.2554,094
10160.6.64.0/2060.6.64.1 to 60.6.79.25460.6.79.2554,094
10260.6.80.0/2060.6.80.1 to 60.6.95.25460.6.95.2554,094
10360.6.96.0/2060.6.96.1 to 60.6.111.25460.6.111.2554,094
10460.6.112.0/2060.6.112.1 to 60.6.127.25460.6.127.2554,094
10560.6.128.0/2060.6.128.1 to 60.6.143.25460.6.143.2554,094
10660.6.144.0/2060.6.144.1 to 60.6.159.25460.6.159.2554,094
10760.6.160.0/2060.6.160.1 to 60.6.175.25460.6.175.2554,094
10860.6.176.0/2060.6.176.1 to 60.6.191.25460.6.191.2554,094
10960.6.192.0/2060.6.192.1 to 60.6.207.25460.6.207.2554,094
11060.6.208.0/2060.6.208.1 to 60.6.223.25460.6.223.2554,094
11160.6.224.0/2060.6.224.1 to 60.6.239.25460.6.239.2554,094
11260.6.240.0/2060.6.240.1 to 60.6.255.25460.6.255.2554,094
11360.7.0.0/2060.7.0.1 to 60.7.15.25460.7.15.2554,094
11460.7.16.0/2060.7.16.1 to 60.7.31.25460.7.31.2554,094
11560.7.32.0/2060.7.32.1 to 60.7.47.25460.7.47.2554,094
11660.7.48.0/2060.7.48.1 to 60.7.63.25460.7.63.2554,094
11760.7.64.0/2060.7.64.1 to 60.7.79.25460.7.79.2554,094
11860.7.80.0/2060.7.80.1 to 60.7.95.25460.7.95.2554,094
11960.7.96.0/2060.7.96.1 to 60.7.111.25460.7.111.2554,094
12060.7.112.0/2060.7.112.1 to 60.7.127.25460.7.127.2554,094
12160.7.128.0/2060.7.128.1 to 60.7.143.25460.7.143.2554,094
12260.7.144.0/2060.7.144.1 to 60.7.159.25460.7.159.2554,094
12360.7.160.0/2060.7.160.1 to 60.7.175.25460.7.175.2554,094
12460.7.176.0/2060.7.176.1 to 60.7.191.25460.7.191.2554,094
12560.7.192.0/2060.7.192.1 to 60.7.207.25460.7.207.2554,094
12660.7.208.0/2060.7.208.1 to 60.7.223.25460.7.223.2554,094
12760.7.224.0/2060.7.224.1 to 60.7.239.25460.7.239.2554,094
12860.7.240.0/2060.7.240.1 to 60.7.255.25460.7.255.2554,094
12960.8.0.0/2060.8.0.1 to 60.8.15.25460.8.15.2554,094
13060.8.16.0/2060.8.16.1 to 60.8.31.25460.8.31.2554,094
13160.8.32.0/2060.8.32.1 to 60.8.47.25460.8.47.2554,094
13260.8.48.0/2060.8.48.1 to 60.8.63.25460.8.63.2554,094
13360.8.64.0/2060.8.64.1 to 60.8.79.25460.8.79.2554,094
13460.8.80.0/2060.8.80.1 to 60.8.95.25460.8.95.2554,094
13560.8.96.0/2060.8.96.1 to 60.8.111.25460.8.111.2554,094
13660.8.112.0/2060.8.112.1 to 60.8.127.25460.8.127.2554,094
13760.8.128.0/2060.8.128.1 to 60.8.143.25460.8.143.2554,094
13860.8.144.0/2060.8.144.1 to 60.8.159.25460.8.159.2554,094
13960.8.160.0/2060.8.160.1 to 60.8.175.25460.8.175.2554,094
14060.8.176.0/2060.8.176.1 to 60.8.191.25460.8.191.2554,094
14160.8.192.0/2060.8.192.1 to 60.8.207.25460.8.207.2554,094
14260.8.208.0/2060.8.208.1 to 60.8.223.25460.8.223.2554,094
14360.8.224.0/2060.8.224.1 to 60.8.239.25460.8.239.2554,094
14460.8.240.0/2060.8.240.1 to 60.8.255.25460.8.255.2554,094
14560.9.0.0/2060.9.0.1 to 60.9.15.25460.9.15.2554,094
14660.9.16.0/2060.9.16.1 to 60.9.31.25460.9.31.2554,094
14760.9.32.0/2060.9.32.1 to 60.9.47.25460.9.47.2554,094
14860.9.48.0/2060.9.48.1 to 60.9.63.25460.9.63.2554,094
14960.9.64.0/2060.9.64.1 to 60.9.79.25460.9.79.2554,094
15060.9.80.0/2060.9.80.1 to 60.9.95.25460.9.95.2554,094
15160.9.96.0/2060.9.96.1 to 60.9.111.25460.9.111.2554,094
15260.9.112.0/2060.9.112.1 to 60.9.127.25460.9.127.2554,094
15360.9.128.0/2060.9.128.1 to 60.9.143.25460.9.143.2554,094
15460.9.144.0/2060.9.144.1 to 60.9.159.25460.9.159.2554,094
15560.9.160.0/2060.9.160.1 to 60.9.175.25460.9.175.2554,094
15660.9.176.0/2060.9.176.1 to 60.9.191.25460.9.191.2554,094
15760.9.192.0/2060.9.192.1 to 60.9.207.25460.9.207.2554,094
15860.9.208.0/2060.9.208.1 to 60.9.223.25460.9.223.2554,094
15960.9.224.0/2060.9.224.1 to 60.9.239.25460.9.239.2554,094
16060.9.240.0/2060.9.240.1 to 60.9.255.25460.9.255.2554,094
16160.10.0.0/2060.10.0.1 to 60.10.15.25460.10.15.2554,094
16260.10.16.0/2060.10.16.1 to 60.10.31.25460.10.31.2554,094
16360.10.32.0/2060.10.32.1 to 60.10.47.25460.10.47.2554,094
16460.10.48.0/2060.10.48.1 to 60.10.63.25460.10.63.2554,094
16560.10.64.0/2060.10.64.1 to 60.10.79.25460.10.79.2554,094
16660.10.80.0/2060.10.80.1 to 60.10.95.25460.10.95.2554,094
16760.10.96.0/2060.10.96.1 to 60.10.111.25460.10.111.2554,094
16860.10.112.0/2060.10.112.1 to 60.10.127.25460.10.127.2554,094
16960.10.128.0/2060.10.128.1 to 60.10.143.25460.10.143.2554,094
17060.10.144.0/2060.10.144.1 to 60.10.159.25460.10.159.2554,094
17160.10.160.0/2060.10.160.1 to 60.10.175.25460.10.175.2554,094
17260.10.176.0/2060.10.176.1 to 60.10.191.25460.10.191.2554,094
17360.10.192.0/2060.10.192.1 to 60.10.207.25460.10.207.2554,094
17460.10.208.0/2060.10.208.1 to 60.10.223.25460.10.223.2554,094
17560.10.224.0/2060.10.224.1 to 60.10.239.25460.10.239.2554,094
17660.10.240.0/2060.10.240.1 to 60.10.255.25460.10.255.2554,094
17760.11.0.0/2060.11.0.1 to 60.11.15.25460.11.15.2554,094
17860.11.16.0/2060.11.16.1 to 60.11.31.25460.11.31.2554,094
17960.11.32.0/2060.11.32.1 to 60.11.47.25460.11.47.2554,094
18060.11.48.0/2060.11.48.1 to 60.11.63.25460.11.63.2554,094
18160.11.64.0/2060.11.64.1 to 60.11.79.25460.11.79.2554,094
18260.11.80.0/2060.11.80.1 to 60.11.95.25460.11.95.2554,094
18360.11.96.0/2060.11.96.1 to 60.11.111.25460.11.111.2554,094
18460.11.112.0/2060.11.112.1 to 60.11.127.25460.11.127.2554,094
18560.11.128.0/2060.11.128.1 to 60.11.143.25460.11.143.2554,094
18660.11.144.0/2060.11.144.1 to 60.11.159.25460.11.159.2554,094
18760.11.160.0/2060.11.160.1 to 60.11.175.25460.11.175.2554,094
18860.11.176.0/2060.11.176.1 to 60.11.191.25460.11.191.2554,094
18960.11.192.0/2060.11.192.1 to 60.11.207.25460.11.207.2554,094
19060.11.208.0/2060.11.208.1 to 60.11.223.25460.11.223.2554,094
19160.11.224.0/2060.11.224.1 to 60.11.239.25460.11.239.2554,094
19260.11.240.0/2060.11.240.1 to 60.11.255.25460.11.255.2554,094
19360.12.0.0/2060.12.0.1 to 60.12.15.25460.12.15.2554,094
19460.12.16.0/2060.12.16.1 to 60.12.31.25460.12.31.2554,094
19560.12.32.0/2060.12.32.1 to 60.12.47.25460.12.47.2554,094
19660.12.48.0/2060.12.48.1 to 60.12.63.25460.12.63.2554,094
19760.12.64.0/2060.12.64.1 to 60.12.79.25460.12.79.2554,094
19860.12.80.0/2060.12.80.1 to 60.12.95.25460.12.95.2554,094
19960.12.96.0/2060.12.96.1 to 60.12.111.25460.12.111.2554,094
20060.12.112.0/2060.12.112.1 to 60.12.127.25460.12.127.2554,094
20160.12.128.0/2060.12.128.1 to 60.12.143.25460.12.143.2554,094
20260.12.144.0/2060.12.144.1 to 60.12.159.25460.12.159.2554,094
20360.12.160.0/2060.12.160.1 to 60.12.175.25460.12.175.2554,094
20460.12.176.0/2060.12.176.1 to 60.12.191.25460.12.191.2554,094
20560.12.192.0/2060.12.192.1 to 60.12.207.25460.12.207.2554,094
20660.12.208.0/2060.12.208.1 to 60.12.223.25460.12.223.2554,094
20760.12.224.0/2060.12.224.1 to 60.12.239.25460.12.239.2554,094
20860.12.240.0/2060.12.240.1 to 60.12.255.25460.12.255.2554,094
20960.13.0.0/2060.13.0.1 to 60.13.15.25460.13.15.2554,094
21060.13.16.0/2060.13.16.1 to 60.13.31.25460.13.31.2554,094
21160.13.32.0/2060.13.32.1 to 60.13.47.25460.13.47.2554,094
21260.13.48.0/2060.13.48.1 to 60.13.63.25460.13.63.2554,094
21360.13.64.0/2060.13.64.1 to 60.13.79.25460.13.79.2554,094
21460.13.80.0/2060.13.80.1 to 60.13.95.25460.13.95.2554,094
21560.13.96.0/2060.13.96.1 to 60.13.111.25460.13.111.2554,094
21660.13.112.0/2060.13.112.1 to 60.13.127.25460.13.127.2554,094
21760.13.128.0/2060.13.128.1 to 60.13.143.25460.13.143.2554,094
21860.13.144.0/2060.13.144.1 to 60.13.159.25460.13.159.2554,094
21960.13.160.0/2060.13.160.1 to 60.13.175.25460.13.175.2554,094
22060.13.176.0/2060.13.176.1 to 60.13.191.25460.13.191.2554,094
22160.13.192.0/2060.13.192.1 to 60.13.207.25460.13.207.2554,094
22260.13.208.0/2060.13.208.1 to 60.13.223.25460.13.223.2554,094
22360.13.224.0/2060.13.224.1 to 60.13.239.25460.13.239.2554,094
22460.13.240.0/2060.13.240.1 to 60.13.255.25460.13.255.2554,094
22560.14.0.0/2060.14.0.1 to 60.14.15.25460.14.15.2554,094
22660.14.16.0/2060.14.16.1 to 60.14.31.25460.14.31.2554,094
22760.14.32.0/2060.14.32.1 to 60.14.47.25460.14.47.2554,094
22860.14.48.0/2060.14.48.1 to 60.14.63.25460.14.63.2554,094
22960.14.64.0/2060.14.64.1 to 60.14.79.25460.14.79.2554,094
23060.14.80.0/2060.14.80.1 to 60.14.95.25460.14.95.2554,094
23160.14.96.0/2060.14.96.1 to 60.14.111.25460.14.111.2554,094
23260.14.112.0/2060.14.112.1 to 60.14.127.25460.14.127.2554,094
23360.14.128.0/2060.14.128.1 to 60.14.143.25460.14.143.2554,094
23460.14.144.0/2060.14.144.1 to 60.14.159.25460.14.159.2554,094
23560.14.160.0/2060.14.160.1 to 60.14.175.25460.14.175.2554,094
23660.14.176.0/2060.14.176.1 to 60.14.191.25460.14.191.2554,094
23760.14.192.0/2060.14.192.1 to 60.14.207.25460.14.207.2554,094
23860.14.208.0/2060.14.208.1 to 60.14.223.25460.14.223.2554,094
23960.14.224.0/2060.14.224.1 to 60.14.239.25460.14.239.2554,094
24060.14.240.0/2060.14.240.1 to 60.14.255.25460.14.255.2554,094
24160.15.0.0/2060.15.0.1 to 60.15.15.25460.15.15.2554,094
24260.15.16.0/2060.15.16.1 to 60.15.31.25460.15.31.2554,094
24360.15.32.0/2060.15.32.1 to 60.15.47.25460.15.47.2554,094
24460.15.48.0/2060.15.48.1 to 60.15.63.25460.15.63.2554,094
24560.15.64.0/2060.15.64.1 to 60.15.79.25460.15.79.2554,094
24660.15.80.0/2060.15.80.1 to 60.15.95.25460.15.95.2554,094
24760.15.96.0/2060.15.96.1 to 60.15.111.25460.15.111.2554,094
24860.15.112.0/2060.15.112.1 to 60.15.127.25460.15.127.2554,094
24960.15.128.0/2060.15.128.1 to 60.15.143.25460.15.143.2554,094
25060.15.144.0/2060.15.144.1 to 60.15.159.25460.15.159.2554,094
25160.15.160.0/2060.15.160.1 to 60.15.175.25460.15.175.2554,094
25260.15.176.0/2060.15.176.1 to 60.15.191.25460.15.191.2554,094
25360.15.192.0/2060.15.192.1 to 60.15.207.25460.15.207.2554,094
25460.15.208.0/2060.15.208.1 to 60.15.223.25460.15.223.2554,094
25560.15.224.0/2060.15.224.1 to 60.15.239.25460.15.239.2554,094
25660.15.240.0/2060.15.240.1 to 60.15.255.25460.15.255.2554,094

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.