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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/17
/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 256 subnets of /17.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
160.0.0.0/1760.0.0.1 to 60.0.127.25460.0.127.25532,766
260.0.128.0/1760.0.128.1 to 60.0.255.25460.0.255.25532,766
360.1.0.0/1760.1.0.1 to 60.1.127.25460.1.127.25532,766
460.1.128.0/1760.1.128.1 to 60.1.255.25460.1.255.25532,766
560.2.0.0/1760.2.0.1 to 60.2.127.25460.2.127.25532,766
660.2.128.0/1760.2.128.1 to 60.2.255.25460.2.255.25532,766
760.3.0.0/1760.3.0.1 to 60.3.127.25460.3.127.25532,766
860.3.128.0/1760.3.128.1 to 60.3.255.25460.3.255.25532,766
960.4.0.0/1760.4.0.1 to 60.4.127.25460.4.127.25532,766
1060.4.128.0/1760.4.128.1 to 60.4.255.25460.4.255.25532,766
1160.5.0.0/1760.5.0.1 to 60.5.127.25460.5.127.25532,766
1260.5.128.0/1760.5.128.1 to 60.5.255.25460.5.255.25532,766
1360.6.0.0/1760.6.0.1 to 60.6.127.25460.6.127.25532,766
1460.6.128.0/1760.6.128.1 to 60.6.255.25460.6.255.25532,766
1560.7.0.0/1760.7.0.1 to 60.7.127.25460.7.127.25532,766
1660.7.128.0/1760.7.128.1 to 60.7.255.25460.7.255.25532,766
1760.8.0.0/1760.8.0.1 to 60.8.127.25460.8.127.25532,766
1860.8.128.0/1760.8.128.1 to 60.8.255.25460.8.255.25532,766
1960.9.0.0/1760.9.0.1 to 60.9.127.25460.9.127.25532,766
2060.9.128.0/1760.9.128.1 to 60.9.255.25460.9.255.25532,766
2160.10.0.0/1760.10.0.1 to 60.10.127.25460.10.127.25532,766
2260.10.128.0/1760.10.128.1 to 60.10.255.25460.10.255.25532,766
2360.11.0.0/1760.11.0.1 to 60.11.127.25460.11.127.25532,766
2460.11.128.0/1760.11.128.1 to 60.11.255.25460.11.255.25532,766
2560.12.0.0/1760.12.0.1 to 60.12.127.25460.12.127.25532,766
2660.12.128.0/1760.12.128.1 to 60.12.255.25460.12.255.25532,766
2760.13.0.0/1760.13.0.1 to 60.13.127.25460.13.127.25532,766
2860.13.128.0/1760.13.128.1 to 60.13.255.25460.13.255.25532,766
2960.14.0.0/1760.14.0.1 to 60.14.127.25460.14.127.25532,766
3060.14.128.0/1760.14.128.1 to 60.14.255.25460.14.255.25532,766
3160.15.0.0/1760.15.0.1 to 60.15.127.25460.15.127.25532,766
3260.15.128.0/1760.15.128.1 to 60.15.255.25460.15.255.25532,766
3360.16.0.0/1760.16.0.1 to 60.16.127.25460.16.127.25532,766
3460.16.128.0/1760.16.128.1 to 60.16.255.25460.16.255.25532,766
3560.17.0.0/1760.17.0.1 to 60.17.127.25460.17.127.25532,766
3660.17.128.0/1760.17.128.1 to 60.17.255.25460.17.255.25532,766
3760.18.0.0/1760.18.0.1 to 60.18.127.25460.18.127.25532,766
3860.18.128.0/1760.18.128.1 to 60.18.255.25460.18.255.25532,766
3960.19.0.0/1760.19.0.1 to 60.19.127.25460.19.127.25532,766
4060.19.128.0/1760.19.128.1 to 60.19.255.25460.19.255.25532,766
4160.20.0.0/1760.20.0.1 to 60.20.127.25460.20.127.25532,766
4260.20.128.0/1760.20.128.1 to 60.20.255.25460.20.255.25532,766
4360.21.0.0/1760.21.0.1 to 60.21.127.25460.21.127.25532,766
4460.21.128.0/1760.21.128.1 to 60.21.255.25460.21.255.25532,766
4560.22.0.0/1760.22.0.1 to 60.22.127.25460.22.127.25532,766
4660.22.128.0/1760.22.128.1 to 60.22.255.25460.22.255.25532,766
4760.23.0.0/1760.23.0.1 to 60.23.127.25460.23.127.25532,766
4860.23.128.0/1760.23.128.1 to 60.23.255.25460.23.255.25532,766
4960.24.0.0/1760.24.0.1 to 60.24.127.25460.24.127.25532,766
5060.24.128.0/1760.24.128.1 to 60.24.255.25460.24.255.25532,766
5160.25.0.0/1760.25.0.1 to 60.25.127.25460.25.127.25532,766
5260.25.128.0/1760.25.128.1 to 60.25.255.25460.25.255.25532,766
5360.26.0.0/1760.26.0.1 to 60.26.127.25460.26.127.25532,766
5460.26.128.0/1760.26.128.1 to 60.26.255.25460.26.255.25532,766
5560.27.0.0/1760.27.0.1 to 60.27.127.25460.27.127.25532,766
5660.27.128.0/1760.27.128.1 to 60.27.255.25460.27.255.25532,766
5760.28.0.0/1760.28.0.1 to 60.28.127.25460.28.127.25532,766
5860.28.128.0/1760.28.128.1 to 60.28.255.25460.28.255.25532,766
5960.29.0.0/1760.29.0.1 to 60.29.127.25460.29.127.25532,766
6060.29.128.0/1760.29.128.1 to 60.29.255.25460.29.255.25532,766
6160.30.0.0/1760.30.0.1 to 60.30.127.25460.30.127.25532,766
6260.30.128.0/1760.30.128.1 to 60.30.255.25460.30.255.25532,766
6360.31.0.0/1760.31.0.1 to 60.31.127.25460.31.127.25532,766
6460.31.128.0/1760.31.128.1 to 60.31.255.25460.31.255.25532,766
6560.32.0.0/1760.32.0.1 to 60.32.127.25460.32.127.25532,766
6660.32.128.0/1760.32.128.1 to 60.32.255.25460.32.255.25532,766
6760.33.0.0/1760.33.0.1 to 60.33.127.25460.33.127.25532,766
6860.33.128.0/1760.33.128.1 to 60.33.255.25460.33.255.25532,766
6960.34.0.0/1760.34.0.1 to 60.34.127.25460.34.127.25532,766
7060.34.128.0/1760.34.128.1 to 60.34.255.25460.34.255.25532,766
7160.35.0.0/1760.35.0.1 to 60.35.127.25460.35.127.25532,766
7260.35.128.0/1760.35.128.1 to 60.35.255.25460.35.255.25532,766
7360.36.0.0/1760.36.0.1 to 60.36.127.25460.36.127.25532,766
7460.36.128.0/1760.36.128.1 to 60.36.255.25460.36.255.25532,766
7560.37.0.0/1760.37.0.1 to 60.37.127.25460.37.127.25532,766
7660.37.128.0/1760.37.128.1 to 60.37.255.25460.37.255.25532,766
7760.38.0.0/1760.38.0.1 to 60.38.127.25460.38.127.25532,766
7860.38.128.0/1760.38.128.1 to 60.38.255.25460.38.255.25532,766
7960.39.0.0/1760.39.0.1 to 60.39.127.25460.39.127.25532,766
8060.39.128.0/1760.39.128.1 to 60.39.255.25460.39.255.25532,766
8160.40.0.0/1760.40.0.1 to 60.40.127.25460.40.127.25532,766
8260.40.128.0/1760.40.128.1 to 60.40.255.25460.40.255.25532,766
8360.41.0.0/1760.41.0.1 to 60.41.127.25460.41.127.25532,766
8460.41.128.0/1760.41.128.1 to 60.41.255.25460.41.255.25532,766
8560.42.0.0/1760.42.0.1 to 60.42.127.25460.42.127.25532,766
8660.42.128.0/1760.42.128.1 to 60.42.255.25460.42.255.25532,766
8760.43.0.0/1760.43.0.1 to 60.43.127.25460.43.127.25532,766
8860.43.128.0/1760.43.128.1 to 60.43.255.25460.43.255.25532,766
8960.44.0.0/1760.44.0.1 to 60.44.127.25460.44.127.25532,766
9060.44.128.0/1760.44.128.1 to 60.44.255.25460.44.255.25532,766
9160.45.0.0/1760.45.0.1 to 60.45.127.25460.45.127.25532,766
9260.45.128.0/1760.45.128.1 to 60.45.255.25460.45.255.25532,766
9360.46.0.0/1760.46.0.1 to 60.46.127.25460.46.127.25532,766
9460.46.128.0/1760.46.128.1 to 60.46.255.25460.46.255.25532,766
9560.47.0.0/1760.47.0.1 to 60.47.127.25460.47.127.25532,766
9660.47.128.0/1760.47.128.1 to 60.47.255.25460.47.255.25532,766
9760.48.0.0/1760.48.0.1 to 60.48.127.25460.48.127.25532,766
9860.48.128.0/1760.48.128.1 to 60.48.255.25460.48.255.25532,766
9960.49.0.0/1760.49.0.1 to 60.49.127.25460.49.127.25532,766
10060.49.128.0/1760.49.128.1 to 60.49.255.25460.49.255.25532,766
10160.50.0.0/1760.50.0.1 to 60.50.127.25460.50.127.25532,766
10260.50.128.0/1760.50.128.1 to 60.50.255.25460.50.255.25532,766
10360.51.0.0/1760.51.0.1 to 60.51.127.25460.51.127.25532,766
10460.51.128.0/1760.51.128.1 to 60.51.255.25460.51.255.25532,766
10560.52.0.0/1760.52.0.1 to 60.52.127.25460.52.127.25532,766
10660.52.128.0/1760.52.128.1 to 60.52.255.25460.52.255.25532,766
10760.53.0.0/1760.53.0.1 to 60.53.127.25460.53.127.25532,766
10860.53.128.0/1760.53.128.1 to 60.53.255.25460.53.255.25532,766
10960.54.0.0/1760.54.0.1 to 60.54.127.25460.54.127.25532,766
11060.54.128.0/1760.54.128.1 to 60.54.255.25460.54.255.25532,766
11160.55.0.0/1760.55.0.1 to 60.55.127.25460.55.127.25532,766
11260.55.128.0/1760.55.128.1 to 60.55.255.25460.55.255.25532,766
11360.56.0.0/1760.56.0.1 to 60.56.127.25460.56.127.25532,766
11460.56.128.0/1760.56.128.1 to 60.56.255.25460.56.255.25532,766
11560.57.0.0/1760.57.0.1 to 60.57.127.25460.57.127.25532,766
11660.57.128.0/1760.57.128.1 to 60.57.255.25460.57.255.25532,766
11760.58.0.0/1760.58.0.1 to 60.58.127.25460.58.127.25532,766
11860.58.128.0/1760.58.128.1 to 60.58.255.25460.58.255.25532,766
11960.59.0.0/1760.59.0.1 to 60.59.127.25460.59.127.25532,766
12060.59.128.0/1760.59.128.1 to 60.59.255.25460.59.255.25532,766
12160.60.0.0/1760.60.0.1 to 60.60.127.25460.60.127.25532,766
12260.60.128.0/1760.60.128.1 to 60.60.255.25460.60.255.25532,766
12360.61.0.0/1760.61.0.1 to 60.61.127.25460.61.127.25532,766
12460.61.128.0/1760.61.128.1 to 60.61.255.25460.61.255.25532,766
12560.62.0.0/1760.62.0.1 to 60.62.127.25460.62.127.25532,766
12660.62.128.0/1760.62.128.1 to 60.62.255.25460.62.255.25532,766
12760.63.0.0/1760.63.0.1 to 60.63.127.25460.63.127.25532,766
12860.63.128.0/1760.63.128.1 to 60.63.255.25460.63.255.25532,766
12960.64.0.0/1760.64.0.1 to 60.64.127.25460.64.127.25532,766
13060.64.128.0/1760.64.128.1 to 60.64.255.25460.64.255.25532,766
13160.65.0.0/1760.65.0.1 to 60.65.127.25460.65.127.25532,766
13260.65.128.0/1760.65.128.1 to 60.65.255.25460.65.255.25532,766
13360.66.0.0/1760.66.0.1 to 60.66.127.25460.66.127.25532,766
13460.66.128.0/1760.66.128.1 to 60.66.255.25460.66.255.25532,766
13560.67.0.0/1760.67.0.1 to 60.67.127.25460.67.127.25532,766
13660.67.128.0/1760.67.128.1 to 60.67.255.25460.67.255.25532,766
13760.68.0.0/1760.68.0.1 to 60.68.127.25460.68.127.25532,766
13860.68.128.0/1760.68.128.1 to 60.68.255.25460.68.255.25532,766
13960.69.0.0/1760.69.0.1 to 60.69.127.25460.69.127.25532,766
14060.69.128.0/1760.69.128.1 to 60.69.255.25460.69.255.25532,766
14160.70.0.0/1760.70.0.1 to 60.70.127.25460.70.127.25532,766
14260.70.128.0/1760.70.128.1 to 60.70.255.25460.70.255.25532,766
14360.71.0.0/1760.71.0.1 to 60.71.127.25460.71.127.25532,766
14460.71.128.0/1760.71.128.1 to 60.71.255.25460.71.255.25532,766
14560.72.0.0/1760.72.0.1 to 60.72.127.25460.72.127.25532,766
14660.72.128.0/1760.72.128.1 to 60.72.255.25460.72.255.25532,766
14760.73.0.0/1760.73.0.1 to 60.73.127.25460.73.127.25532,766
14860.73.128.0/1760.73.128.1 to 60.73.255.25460.73.255.25532,766
14960.74.0.0/1760.74.0.1 to 60.74.127.25460.74.127.25532,766
15060.74.128.0/1760.74.128.1 to 60.74.255.25460.74.255.25532,766
15160.75.0.0/1760.75.0.1 to 60.75.127.25460.75.127.25532,766
15260.75.128.0/1760.75.128.1 to 60.75.255.25460.75.255.25532,766
15360.76.0.0/1760.76.0.1 to 60.76.127.25460.76.127.25532,766
15460.76.128.0/1760.76.128.1 to 60.76.255.25460.76.255.25532,766
15560.77.0.0/1760.77.0.1 to 60.77.127.25460.77.127.25532,766
15660.77.128.0/1760.77.128.1 to 60.77.255.25460.77.255.25532,766
15760.78.0.0/1760.78.0.1 to 60.78.127.25460.78.127.25532,766
15860.78.128.0/1760.78.128.1 to 60.78.255.25460.78.255.25532,766
15960.79.0.0/1760.79.0.1 to 60.79.127.25460.79.127.25532,766
16060.79.128.0/1760.79.128.1 to 60.79.255.25460.79.255.25532,766
16160.80.0.0/1760.80.0.1 to 60.80.127.25460.80.127.25532,766
16260.80.128.0/1760.80.128.1 to 60.80.255.25460.80.255.25532,766
16360.81.0.0/1760.81.0.1 to 60.81.127.25460.81.127.25532,766
16460.81.128.0/1760.81.128.1 to 60.81.255.25460.81.255.25532,766
16560.82.0.0/1760.82.0.1 to 60.82.127.25460.82.127.25532,766
16660.82.128.0/1760.82.128.1 to 60.82.255.25460.82.255.25532,766
16760.83.0.0/1760.83.0.1 to 60.83.127.25460.83.127.25532,766
16860.83.128.0/1760.83.128.1 to 60.83.255.25460.83.255.25532,766
16960.84.0.0/1760.84.0.1 to 60.84.127.25460.84.127.25532,766
17060.84.128.0/1760.84.128.1 to 60.84.255.25460.84.255.25532,766
17160.85.0.0/1760.85.0.1 to 60.85.127.25460.85.127.25532,766
17260.85.128.0/1760.85.128.1 to 60.85.255.25460.85.255.25532,766
17360.86.0.0/1760.86.0.1 to 60.86.127.25460.86.127.25532,766
17460.86.128.0/1760.86.128.1 to 60.86.255.25460.86.255.25532,766
17560.87.0.0/1760.87.0.1 to 60.87.127.25460.87.127.25532,766
17660.87.128.0/1760.87.128.1 to 60.87.255.25460.87.255.25532,766
17760.88.0.0/1760.88.0.1 to 60.88.127.25460.88.127.25532,766
17860.88.128.0/1760.88.128.1 to 60.88.255.25460.88.255.25532,766
17960.89.0.0/1760.89.0.1 to 60.89.127.25460.89.127.25532,766
18060.89.128.0/1760.89.128.1 to 60.89.255.25460.89.255.25532,766
18160.90.0.0/1760.90.0.1 to 60.90.127.25460.90.127.25532,766
18260.90.128.0/1760.90.128.1 to 60.90.255.25460.90.255.25532,766
18360.91.0.0/1760.91.0.1 to 60.91.127.25460.91.127.25532,766
18460.91.128.0/1760.91.128.1 to 60.91.255.25460.91.255.25532,766
18560.92.0.0/1760.92.0.1 to 60.92.127.25460.92.127.25532,766
18660.92.128.0/1760.92.128.1 to 60.92.255.25460.92.255.25532,766
18760.93.0.0/1760.93.0.1 to 60.93.127.25460.93.127.25532,766
18860.93.128.0/1760.93.128.1 to 60.93.255.25460.93.255.25532,766
18960.94.0.0/1760.94.0.1 to 60.94.127.25460.94.127.25532,766
19060.94.128.0/1760.94.128.1 to 60.94.255.25460.94.255.25532,766
19160.95.0.0/1760.95.0.1 to 60.95.127.25460.95.127.25532,766
19260.95.128.0/1760.95.128.1 to 60.95.255.25460.95.255.25532,766
19360.96.0.0/1760.96.0.1 to 60.96.127.25460.96.127.25532,766
19460.96.128.0/1760.96.128.1 to 60.96.255.25460.96.255.25532,766
19560.97.0.0/1760.97.0.1 to 60.97.127.25460.97.127.25532,766
19660.97.128.0/1760.97.128.1 to 60.97.255.25460.97.255.25532,766
19760.98.0.0/1760.98.0.1 to 60.98.127.25460.98.127.25532,766
19860.98.128.0/1760.98.128.1 to 60.98.255.25460.98.255.25532,766
19960.99.0.0/1760.99.0.1 to 60.99.127.25460.99.127.25532,766
20060.99.128.0/1760.99.128.1 to 60.99.255.25460.99.255.25532,766
20160.100.0.0/1760.100.0.1 to 60.100.127.25460.100.127.25532,766
20260.100.128.0/1760.100.128.1 to 60.100.255.25460.100.255.25532,766
20360.101.0.0/1760.101.0.1 to 60.101.127.25460.101.127.25532,766
20460.101.128.0/1760.101.128.1 to 60.101.255.25460.101.255.25532,766
20560.102.0.0/1760.102.0.1 to 60.102.127.25460.102.127.25532,766
20660.102.128.0/1760.102.128.1 to 60.102.255.25460.102.255.25532,766
20760.103.0.0/1760.103.0.1 to 60.103.127.25460.103.127.25532,766
20860.103.128.0/1760.103.128.1 to 60.103.255.25460.103.255.25532,766
20960.104.0.0/1760.104.0.1 to 60.104.127.25460.104.127.25532,766
21060.104.128.0/1760.104.128.1 to 60.104.255.25460.104.255.25532,766
21160.105.0.0/1760.105.0.1 to 60.105.127.25460.105.127.25532,766
21260.105.128.0/1760.105.128.1 to 60.105.255.25460.105.255.25532,766
21360.106.0.0/1760.106.0.1 to 60.106.127.25460.106.127.25532,766
21460.106.128.0/1760.106.128.1 to 60.106.255.25460.106.255.25532,766
21560.107.0.0/1760.107.0.1 to 60.107.127.25460.107.127.25532,766
21660.107.128.0/1760.107.128.1 to 60.107.255.25460.107.255.25532,766
21760.108.0.0/1760.108.0.1 to 60.108.127.25460.108.127.25532,766
21860.108.128.0/1760.108.128.1 to 60.108.255.25460.108.255.25532,766
21960.109.0.0/1760.109.0.1 to 60.109.127.25460.109.127.25532,766
22060.109.128.0/1760.109.128.1 to 60.109.255.25460.109.255.25532,766
22160.110.0.0/1760.110.0.1 to 60.110.127.25460.110.127.25532,766
22260.110.128.0/1760.110.128.1 to 60.110.255.25460.110.255.25532,766
22360.111.0.0/1760.111.0.1 to 60.111.127.25460.111.127.25532,766
22460.111.128.0/1760.111.128.1 to 60.111.255.25460.111.255.25532,766
22560.112.0.0/1760.112.0.1 to 60.112.127.25460.112.127.25532,766
22660.112.128.0/1760.112.128.1 to 60.112.255.25460.112.255.25532,766
22760.113.0.0/1760.113.0.1 to 60.113.127.25460.113.127.25532,766
22860.113.128.0/1760.113.128.1 to 60.113.255.25460.113.255.25532,766
22960.114.0.0/1760.114.0.1 to 60.114.127.25460.114.127.25532,766
23060.114.128.0/1760.114.128.1 to 60.114.255.25460.114.255.25532,766
23160.115.0.0/1760.115.0.1 to 60.115.127.25460.115.127.25532,766
23260.115.128.0/1760.115.128.1 to 60.115.255.25460.115.255.25532,766
23360.116.0.0/1760.116.0.1 to 60.116.127.25460.116.127.25532,766
23460.116.128.0/1760.116.128.1 to 60.116.255.25460.116.255.25532,766
23560.117.0.0/1760.117.0.1 to 60.117.127.25460.117.127.25532,766
23660.117.128.0/1760.117.128.1 to 60.117.255.25460.117.255.25532,766
23760.118.0.0/1760.118.0.1 to 60.118.127.25460.118.127.25532,766
23860.118.128.0/1760.118.128.1 to 60.118.255.25460.118.255.25532,766
23960.119.0.0/1760.119.0.1 to 60.119.127.25460.119.127.25532,766
24060.119.128.0/1760.119.128.1 to 60.119.255.25460.119.255.25532,766
24160.120.0.0/1760.120.0.1 to 60.120.127.25460.120.127.25532,766
24260.120.128.0/1760.120.128.1 to 60.120.255.25460.120.255.25532,766
24360.121.0.0/1760.121.0.1 to 60.121.127.25460.121.127.25532,766
24460.121.128.0/1760.121.128.1 to 60.121.255.25460.121.255.25532,766
24560.122.0.0/1760.122.0.1 to 60.122.127.25460.122.127.25532,766
24660.122.128.0/1760.122.128.1 to 60.122.255.25460.122.255.25532,766
24760.123.0.0/1760.123.0.1 to 60.123.127.25460.123.127.25532,766
24860.123.128.0/1760.123.128.1 to 60.123.255.25460.123.255.25532,766
24960.124.0.0/1760.124.0.1 to 60.124.127.25460.124.127.25532,766
25060.124.128.0/1760.124.128.1 to 60.124.255.25460.124.255.25532,766
25160.125.0.0/1760.125.0.1 to 60.125.127.25460.125.127.25532,766
25260.125.128.0/1760.125.128.1 to 60.125.255.25460.125.255.25532,766
25360.126.0.0/1760.126.0.1 to 60.126.127.25460.126.127.25532,766
25460.126.128.0/1760.126.128.1 to 60.126.255.25460.126.255.25532,766
25560.127.0.0/1760.127.0.1 to 60.127.127.25460.127.127.25532,766
25660.127.128.0/1760.127.128.1 to 60.127.255.25460.127.255.25532,766

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.