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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.

Network60.2.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
60.2.0.0
Broadcast address
60.2.127.255
First usable
60.2.0.1
Last usable
60.2.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Public public
Old class
A (default /8)
As numbers
Hex 3C020000 · Integer 1006764032 to 1006796799
Reverse DNS zones
0.2.60.in-addr.arpa
1.2.60.in-addr.arpa
2.2.60.in-addr.arpa
3.2.60.in-addr.arpa
4.2.60.in-addr.arpa
5.2.60.in-addr.arpa
6.2.60.in-addr.arpa
7.2.60.in-addr.arpa
8.2.60.in-addr.arpa
9.2.60.in-addr.arpa
10.2.60.in-addr.arpa
11.2.60.in-addr.arpa
12.2.60.in-addr.arpa
13.2.60.in-addr.arpa
14.2.60.in-addr.arpa
15.2.60.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111100.00000010.00000000.0000000060.2.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network00111100.00000010.00000000.0000000060.2.0.0
Broadcast00111100.00000010.01111111.1111111160.2.127.255
Split into smaller subnets/26
/18 (2)/19 (4)/20 (8)/21 (16)/22 (32)/23 (64)/24 (128)/25 (256)/26 (512)/27 (1,024)/28 (2,048)/29 (4,096)

60.2.0.0/17 makes 512 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
160.2.0.0/2660.2.0.1 to 60.2.0.6260.2.0.6362
260.2.0.64/2660.2.0.65 to 60.2.0.12660.2.0.12762
360.2.0.128/2660.2.0.129 to 60.2.0.19060.2.0.19162
460.2.0.192/2660.2.0.193 to 60.2.0.25460.2.0.25562
560.2.1.0/2660.2.1.1 to 60.2.1.6260.2.1.6362
660.2.1.64/2660.2.1.65 to 60.2.1.12660.2.1.12762
760.2.1.128/2660.2.1.129 to 60.2.1.19060.2.1.19162
860.2.1.192/2660.2.1.193 to 60.2.1.25460.2.1.25562
960.2.2.0/2660.2.2.1 to 60.2.2.6260.2.2.6362
1060.2.2.64/2660.2.2.65 to 60.2.2.12660.2.2.12762
1160.2.2.128/2660.2.2.129 to 60.2.2.19060.2.2.19162
1260.2.2.192/2660.2.2.193 to 60.2.2.25460.2.2.25562
1360.2.3.0/2660.2.3.1 to 60.2.3.6260.2.3.6362
1460.2.3.64/2660.2.3.65 to 60.2.3.12660.2.3.12762
1560.2.3.128/2660.2.3.129 to 60.2.3.19060.2.3.19162
1660.2.3.192/2660.2.3.193 to 60.2.3.25460.2.3.25562
1760.2.4.0/2660.2.4.1 to 60.2.4.6260.2.4.6362
1860.2.4.64/2660.2.4.65 to 60.2.4.12660.2.4.12762
1960.2.4.128/2660.2.4.129 to 60.2.4.19060.2.4.19162
2060.2.4.192/2660.2.4.193 to 60.2.4.25460.2.4.25562
2160.2.5.0/2660.2.5.1 to 60.2.5.6260.2.5.6362
2260.2.5.64/2660.2.5.65 to 60.2.5.12660.2.5.12762
2360.2.5.128/2660.2.5.129 to 60.2.5.19060.2.5.19162
2460.2.5.192/2660.2.5.193 to 60.2.5.25460.2.5.25562
2560.2.6.0/2660.2.6.1 to 60.2.6.6260.2.6.6362
2660.2.6.64/2660.2.6.65 to 60.2.6.12660.2.6.12762
2760.2.6.128/2660.2.6.129 to 60.2.6.19060.2.6.19162
2860.2.6.192/2660.2.6.193 to 60.2.6.25460.2.6.25562
2960.2.7.0/2660.2.7.1 to 60.2.7.6260.2.7.6362
3060.2.7.64/2660.2.7.65 to 60.2.7.12660.2.7.12762
3160.2.7.128/2660.2.7.129 to 60.2.7.19060.2.7.19162
3260.2.7.192/2660.2.7.193 to 60.2.7.25460.2.7.25562
3360.2.8.0/2660.2.8.1 to 60.2.8.6260.2.8.6362
3460.2.8.64/2660.2.8.65 to 60.2.8.12660.2.8.12762
3560.2.8.128/2660.2.8.129 to 60.2.8.19060.2.8.19162
3660.2.8.192/2660.2.8.193 to 60.2.8.25460.2.8.25562
3760.2.9.0/2660.2.9.1 to 60.2.9.6260.2.9.6362
3860.2.9.64/2660.2.9.65 to 60.2.9.12660.2.9.12762
3960.2.9.128/2660.2.9.129 to 60.2.9.19060.2.9.19162
4060.2.9.192/2660.2.9.193 to 60.2.9.25460.2.9.25562
4160.2.10.0/2660.2.10.1 to 60.2.10.6260.2.10.6362
4260.2.10.64/2660.2.10.65 to 60.2.10.12660.2.10.12762
4360.2.10.128/2660.2.10.129 to 60.2.10.19060.2.10.19162
4460.2.10.192/2660.2.10.193 to 60.2.10.25460.2.10.25562
4560.2.11.0/2660.2.11.1 to 60.2.11.6260.2.11.6362
4660.2.11.64/2660.2.11.65 to 60.2.11.12660.2.11.12762
4760.2.11.128/2660.2.11.129 to 60.2.11.19060.2.11.19162
4860.2.11.192/2660.2.11.193 to 60.2.11.25460.2.11.25562
4960.2.12.0/2660.2.12.1 to 60.2.12.6260.2.12.6362
5060.2.12.64/2660.2.12.65 to 60.2.12.12660.2.12.12762
5160.2.12.128/2660.2.12.129 to 60.2.12.19060.2.12.19162
5260.2.12.192/2660.2.12.193 to 60.2.12.25460.2.12.25562
5360.2.13.0/2660.2.13.1 to 60.2.13.6260.2.13.6362
5460.2.13.64/2660.2.13.65 to 60.2.13.12660.2.13.12762
5560.2.13.128/2660.2.13.129 to 60.2.13.19060.2.13.19162
5660.2.13.192/2660.2.13.193 to 60.2.13.25460.2.13.25562
5760.2.14.0/2660.2.14.1 to 60.2.14.6260.2.14.6362
5860.2.14.64/2660.2.14.65 to 60.2.14.12660.2.14.12762
5960.2.14.128/2660.2.14.129 to 60.2.14.19060.2.14.19162
6060.2.14.192/2660.2.14.193 to 60.2.14.25460.2.14.25562
6160.2.15.0/2660.2.15.1 to 60.2.15.6260.2.15.6362
6260.2.15.64/2660.2.15.65 to 60.2.15.12660.2.15.12762
6360.2.15.128/2660.2.15.129 to 60.2.15.19060.2.15.19162
6460.2.15.192/2660.2.15.193 to 60.2.15.25460.2.15.25562
6560.2.16.0/2660.2.16.1 to 60.2.16.6260.2.16.6362
6660.2.16.64/2660.2.16.65 to 60.2.16.12660.2.16.12762
6760.2.16.128/2660.2.16.129 to 60.2.16.19060.2.16.19162
6860.2.16.192/2660.2.16.193 to 60.2.16.25460.2.16.25562
6960.2.17.0/2660.2.17.1 to 60.2.17.6260.2.17.6362
7060.2.17.64/2660.2.17.65 to 60.2.17.12660.2.17.12762
7160.2.17.128/2660.2.17.129 to 60.2.17.19060.2.17.19162
7260.2.17.192/2660.2.17.193 to 60.2.17.25460.2.17.25562
7360.2.18.0/2660.2.18.1 to 60.2.18.6260.2.18.6362
7460.2.18.64/2660.2.18.65 to 60.2.18.12660.2.18.12762
7560.2.18.128/2660.2.18.129 to 60.2.18.19060.2.18.19162
7660.2.18.192/2660.2.18.193 to 60.2.18.25460.2.18.25562
7760.2.19.0/2660.2.19.1 to 60.2.19.6260.2.19.6362
7860.2.19.64/2660.2.19.65 to 60.2.19.12660.2.19.12762
7960.2.19.128/2660.2.19.129 to 60.2.19.19060.2.19.19162
8060.2.19.192/2660.2.19.193 to 60.2.19.25460.2.19.25562
8160.2.20.0/2660.2.20.1 to 60.2.20.6260.2.20.6362
8260.2.20.64/2660.2.20.65 to 60.2.20.12660.2.20.12762
8360.2.20.128/2660.2.20.129 to 60.2.20.19060.2.20.19162
8460.2.20.192/2660.2.20.193 to 60.2.20.25460.2.20.25562
8560.2.21.0/2660.2.21.1 to 60.2.21.6260.2.21.6362
8660.2.21.64/2660.2.21.65 to 60.2.21.12660.2.21.12762
8760.2.21.128/2660.2.21.129 to 60.2.21.19060.2.21.19162
8860.2.21.192/2660.2.21.193 to 60.2.21.25460.2.21.25562
8960.2.22.0/2660.2.22.1 to 60.2.22.6260.2.22.6362
9060.2.22.64/2660.2.22.65 to 60.2.22.12660.2.22.12762
9160.2.22.128/2660.2.22.129 to 60.2.22.19060.2.22.19162
9260.2.22.192/2660.2.22.193 to 60.2.22.25460.2.22.25562
9360.2.23.0/2660.2.23.1 to 60.2.23.6260.2.23.6362
9460.2.23.64/2660.2.23.65 to 60.2.23.12660.2.23.12762
9560.2.23.128/2660.2.23.129 to 60.2.23.19060.2.23.19162
9660.2.23.192/2660.2.23.193 to 60.2.23.25460.2.23.25562
9760.2.24.0/2660.2.24.1 to 60.2.24.6260.2.24.6362
9860.2.24.64/2660.2.24.65 to 60.2.24.12660.2.24.12762
9960.2.24.128/2660.2.24.129 to 60.2.24.19060.2.24.19162
10060.2.24.192/2660.2.24.193 to 60.2.24.25460.2.24.25562
10160.2.25.0/2660.2.25.1 to 60.2.25.6260.2.25.6362
10260.2.25.64/2660.2.25.65 to 60.2.25.12660.2.25.12762
10360.2.25.128/2660.2.25.129 to 60.2.25.19060.2.25.19162
10460.2.25.192/2660.2.25.193 to 60.2.25.25460.2.25.25562
10560.2.26.0/2660.2.26.1 to 60.2.26.6260.2.26.6362
10660.2.26.64/2660.2.26.65 to 60.2.26.12660.2.26.12762
10760.2.26.128/2660.2.26.129 to 60.2.26.19060.2.26.19162
10860.2.26.192/2660.2.26.193 to 60.2.26.25460.2.26.25562
10960.2.27.0/2660.2.27.1 to 60.2.27.6260.2.27.6362
11060.2.27.64/2660.2.27.65 to 60.2.27.12660.2.27.12762
11160.2.27.128/2660.2.27.129 to 60.2.27.19060.2.27.19162
11260.2.27.192/2660.2.27.193 to 60.2.27.25460.2.27.25562
11360.2.28.0/2660.2.28.1 to 60.2.28.6260.2.28.6362
11460.2.28.64/2660.2.28.65 to 60.2.28.12660.2.28.12762
11560.2.28.128/2660.2.28.129 to 60.2.28.19060.2.28.19162
11660.2.28.192/2660.2.28.193 to 60.2.28.25460.2.28.25562
11760.2.29.0/2660.2.29.1 to 60.2.29.6260.2.29.6362
11860.2.29.64/2660.2.29.65 to 60.2.29.12660.2.29.12762
11960.2.29.128/2660.2.29.129 to 60.2.29.19060.2.29.19162
12060.2.29.192/2660.2.29.193 to 60.2.29.25460.2.29.25562
12160.2.30.0/2660.2.30.1 to 60.2.30.6260.2.30.6362
12260.2.30.64/2660.2.30.65 to 60.2.30.12660.2.30.12762
12360.2.30.128/2660.2.30.129 to 60.2.30.19060.2.30.19162
12460.2.30.192/2660.2.30.193 to 60.2.30.25460.2.30.25562
12560.2.31.0/2660.2.31.1 to 60.2.31.6260.2.31.6362
12660.2.31.64/2660.2.31.65 to 60.2.31.12660.2.31.12762
12760.2.31.128/2660.2.31.129 to 60.2.31.19060.2.31.19162
12860.2.31.192/2660.2.31.193 to 60.2.31.25460.2.31.25562
12960.2.32.0/2660.2.32.1 to 60.2.32.6260.2.32.6362
13060.2.32.64/2660.2.32.65 to 60.2.32.12660.2.32.12762
13160.2.32.128/2660.2.32.129 to 60.2.32.19060.2.32.19162
13260.2.32.192/2660.2.32.193 to 60.2.32.25460.2.32.25562
13360.2.33.0/2660.2.33.1 to 60.2.33.6260.2.33.6362
13460.2.33.64/2660.2.33.65 to 60.2.33.12660.2.33.12762
13560.2.33.128/2660.2.33.129 to 60.2.33.19060.2.33.19162
13660.2.33.192/2660.2.33.193 to 60.2.33.25460.2.33.25562
13760.2.34.0/2660.2.34.1 to 60.2.34.6260.2.34.6362
13860.2.34.64/2660.2.34.65 to 60.2.34.12660.2.34.12762
13960.2.34.128/2660.2.34.129 to 60.2.34.19060.2.34.19162
14060.2.34.192/2660.2.34.193 to 60.2.34.25460.2.34.25562
14160.2.35.0/2660.2.35.1 to 60.2.35.6260.2.35.6362
14260.2.35.64/2660.2.35.65 to 60.2.35.12660.2.35.12762
14360.2.35.128/2660.2.35.129 to 60.2.35.19060.2.35.19162
14460.2.35.192/2660.2.35.193 to 60.2.35.25460.2.35.25562
14560.2.36.0/2660.2.36.1 to 60.2.36.6260.2.36.6362
14660.2.36.64/2660.2.36.65 to 60.2.36.12660.2.36.12762
14760.2.36.128/2660.2.36.129 to 60.2.36.19060.2.36.19162
14860.2.36.192/2660.2.36.193 to 60.2.36.25460.2.36.25562
14960.2.37.0/2660.2.37.1 to 60.2.37.6260.2.37.6362
15060.2.37.64/2660.2.37.65 to 60.2.37.12660.2.37.12762
15160.2.37.128/2660.2.37.129 to 60.2.37.19060.2.37.19162
15260.2.37.192/2660.2.37.193 to 60.2.37.25460.2.37.25562
15360.2.38.0/2660.2.38.1 to 60.2.38.6260.2.38.6362
15460.2.38.64/2660.2.38.65 to 60.2.38.12660.2.38.12762
15560.2.38.128/2660.2.38.129 to 60.2.38.19060.2.38.19162
15660.2.38.192/2660.2.38.193 to 60.2.38.25460.2.38.25562
15760.2.39.0/2660.2.39.1 to 60.2.39.6260.2.39.6362
15860.2.39.64/2660.2.39.65 to 60.2.39.12660.2.39.12762
15960.2.39.128/2660.2.39.129 to 60.2.39.19060.2.39.19162
16060.2.39.192/2660.2.39.193 to 60.2.39.25460.2.39.25562
16160.2.40.0/2660.2.40.1 to 60.2.40.6260.2.40.6362
16260.2.40.64/2660.2.40.65 to 60.2.40.12660.2.40.12762
16360.2.40.128/2660.2.40.129 to 60.2.40.19060.2.40.19162
16460.2.40.192/2660.2.40.193 to 60.2.40.25460.2.40.25562
16560.2.41.0/2660.2.41.1 to 60.2.41.6260.2.41.6362
16660.2.41.64/2660.2.41.65 to 60.2.41.12660.2.41.12762
16760.2.41.128/2660.2.41.129 to 60.2.41.19060.2.41.19162
16860.2.41.192/2660.2.41.193 to 60.2.41.25460.2.41.25562
16960.2.42.0/2660.2.42.1 to 60.2.42.6260.2.42.6362
17060.2.42.64/2660.2.42.65 to 60.2.42.12660.2.42.12762
17160.2.42.128/2660.2.42.129 to 60.2.42.19060.2.42.19162
17260.2.42.192/2660.2.42.193 to 60.2.42.25460.2.42.25562
17360.2.43.0/2660.2.43.1 to 60.2.43.6260.2.43.6362
17460.2.43.64/2660.2.43.65 to 60.2.43.12660.2.43.12762
17560.2.43.128/2660.2.43.129 to 60.2.43.19060.2.43.19162
17660.2.43.192/2660.2.43.193 to 60.2.43.25460.2.43.25562
17760.2.44.0/2660.2.44.1 to 60.2.44.6260.2.44.6362
17860.2.44.64/2660.2.44.65 to 60.2.44.12660.2.44.12762
17960.2.44.128/2660.2.44.129 to 60.2.44.19060.2.44.19162
18060.2.44.192/2660.2.44.193 to 60.2.44.25460.2.44.25562
18160.2.45.0/2660.2.45.1 to 60.2.45.6260.2.45.6362
18260.2.45.64/2660.2.45.65 to 60.2.45.12660.2.45.12762
18360.2.45.128/2660.2.45.129 to 60.2.45.19060.2.45.19162
18460.2.45.192/2660.2.45.193 to 60.2.45.25460.2.45.25562
18560.2.46.0/2660.2.46.1 to 60.2.46.6260.2.46.6362
18660.2.46.64/2660.2.46.65 to 60.2.46.12660.2.46.12762
18760.2.46.128/2660.2.46.129 to 60.2.46.19060.2.46.19162
18860.2.46.192/2660.2.46.193 to 60.2.46.25460.2.46.25562
18960.2.47.0/2660.2.47.1 to 60.2.47.6260.2.47.6362
19060.2.47.64/2660.2.47.65 to 60.2.47.12660.2.47.12762
19160.2.47.128/2660.2.47.129 to 60.2.47.19060.2.47.19162
19260.2.47.192/2660.2.47.193 to 60.2.47.25460.2.47.25562
19360.2.48.0/2660.2.48.1 to 60.2.48.6260.2.48.6362
19460.2.48.64/2660.2.48.65 to 60.2.48.12660.2.48.12762
19560.2.48.128/2660.2.48.129 to 60.2.48.19060.2.48.19162
19660.2.48.192/2660.2.48.193 to 60.2.48.25460.2.48.25562
19760.2.49.0/2660.2.49.1 to 60.2.49.6260.2.49.6362
19860.2.49.64/2660.2.49.65 to 60.2.49.12660.2.49.12762
19960.2.49.128/2660.2.49.129 to 60.2.49.19060.2.49.19162
20060.2.49.192/2660.2.49.193 to 60.2.49.25460.2.49.25562
20160.2.50.0/2660.2.50.1 to 60.2.50.6260.2.50.6362
20260.2.50.64/2660.2.50.65 to 60.2.50.12660.2.50.12762
20360.2.50.128/2660.2.50.129 to 60.2.50.19060.2.50.19162
20460.2.50.192/2660.2.50.193 to 60.2.50.25460.2.50.25562
20560.2.51.0/2660.2.51.1 to 60.2.51.6260.2.51.6362
20660.2.51.64/2660.2.51.65 to 60.2.51.12660.2.51.12762
20760.2.51.128/2660.2.51.129 to 60.2.51.19060.2.51.19162
20860.2.51.192/2660.2.51.193 to 60.2.51.25460.2.51.25562
20960.2.52.0/2660.2.52.1 to 60.2.52.6260.2.52.6362
21060.2.52.64/2660.2.52.65 to 60.2.52.12660.2.52.12762
21160.2.52.128/2660.2.52.129 to 60.2.52.19060.2.52.19162
21260.2.52.192/2660.2.52.193 to 60.2.52.25460.2.52.25562
21360.2.53.0/2660.2.53.1 to 60.2.53.6260.2.53.6362
21460.2.53.64/2660.2.53.65 to 60.2.53.12660.2.53.12762
21560.2.53.128/2660.2.53.129 to 60.2.53.19060.2.53.19162
21660.2.53.192/2660.2.53.193 to 60.2.53.25460.2.53.25562
21760.2.54.0/2660.2.54.1 to 60.2.54.6260.2.54.6362
21860.2.54.64/2660.2.54.65 to 60.2.54.12660.2.54.12762
21960.2.54.128/2660.2.54.129 to 60.2.54.19060.2.54.19162
22060.2.54.192/2660.2.54.193 to 60.2.54.25460.2.54.25562
22160.2.55.0/2660.2.55.1 to 60.2.55.6260.2.55.6362
22260.2.55.64/2660.2.55.65 to 60.2.55.12660.2.55.12762
22360.2.55.128/2660.2.55.129 to 60.2.55.19060.2.55.19162
22460.2.55.192/2660.2.55.193 to 60.2.55.25460.2.55.25562
22560.2.56.0/2660.2.56.1 to 60.2.56.6260.2.56.6362
22660.2.56.64/2660.2.56.65 to 60.2.56.12660.2.56.12762
22760.2.56.128/2660.2.56.129 to 60.2.56.19060.2.56.19162
22860.2.56.192/2660.2.56.193 to 60.2.56.25460.2.56.25562
22960.2.57.0/2660.2.57.1 to 60.2.57.6260.2.57.6362
23060.2.57.64/2660.2.57.65 to 60.2.57.12660.2.57.12762
23160.2.57.128/2660.2.57.129 to 60.2.57.19060.2.57.19162
23260.2.57.192/2660.2.57.193 to 60.2.57.25460.2.57.25562
23360.2.58.0/2660.2.58.1 to 60.2.58.6260.2.58.6362
23460.2.58.64/2660.2.58.65 to 60.2.58.12660.2.58.12762
23560.2.58.128/2660.2.58.129 to 60.2.58.19060.2.58.19162
23660.2.58.192/2660.2.58.193 to 60.2.58.25460.2.58.25562
23760.2.59.0/2660.2.59.1 to 60.2.59.6260.2.59.6362
23860.2.59.64/2660.2.59.65 to 60.2.59.12660.2.59.12762
23960.2.59.128/2660.2.59.129 to 60.2.59.19060.2.59.19162
24060.2.59.192/2660.2.59.193 to 60.2.59.25460.2.59.25562
24160.2.60.0/2660.2.60.1 to 60.2.60.6260.2.60.6362
24260.2.60.64/2660.2.60.65 to 60.2.60.12660.2.60.12762
24360.2.60.128/2660.2.60.129 to 60.2.60.19060.2.60.19162
24460.2.60.192/2660.2.60.193 to 60.2.60.25460.2.60.25562
24560.2.61.0/2660.2.61.1 to 60.2.61.6260.2.61.6362
24660.2.61.64/2660.2.61.65 to 60.2.61.12660.2.61.12762
24760.2.61.128/2660.2.61.129 to 60.2.61.19060.2.61.19162
24860.2.61.192/2660.2.61.193 to 60.2.61.25460.2.61.25562
24960.2.62.0/2660.2.62.1 to 60.2.62.6260.2.62.6362
25060.2.62.64/2660.2.62.65 to 60.2.62.12660.2.62.12762
25160.2.62.128/2660.2.62.129 to 60.2.62.19060.2.62.19162
25260.2.62.192/2660.2.62.193 to 60.2.62.25460.2.62.25562
25360.2.63.0/2660.2.63.1 to 60.2.63.6260.2.63.6362
25460.2.63.64/2660.2.63.65 to 60.2.63.12660.2.63.12762
25560.2.63.128/2660.2.63.129 to 60.2.63.19060.2.63.19162
25660.2.63.192/2660.2.63.193 to 60.2.63.25460.2.63.25562

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.