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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.

Network60.136.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
60.136.0.0
Broadcast address
60.143.255.255
First usable
60.136.0.1
Last usable
60.143.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 3C880000 · Integer 1015545856 to 1016070143
Reverse DNS zones
136.60.in-addr.arpa
137.60.in-addr.arpa
138.60.in-addr.arpa
139.60.in-addr.arpa
140.60.in-addr.arpa
141.60.in-addr.arpa
142.60.in-addr.arpa
143.60.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111100.10001000.00000000.0000000060.136.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network00111100.10001000.00000000.0000000060.136.0.0
Broadcast00111100.10001111.11111111.1111111160.143.255.255
Split into smaller subnets/25
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

60.136.0.0/13 makes 4,096 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
160.136.0.0/2560.136.0.1 to 60.136.0.12660.136.0.127126
260.136.0.128/2560.136.0.129 to 60.136.0.25460.136.0.255126
360.136.1.0/2560.136.1.1 to 60.136.1.12660.136.1.127126
460.136.1.128/2560.136.1.129 to 60.136.1.25460.136.1.255126
560.136.2.0/2560.136.2.1 to 60.136.2.12660.136.2.127126
660.136.2.128/2560.136.2.129 to 60.136.2.25460.136.2.255126
760.136.3.0/2560.136.3.1 to 60.136.3.12660.136.3.127126
860.136.3.128/2560.136.3.129 to 60.136.3.25460.136.3.255126
960.136.4.0/2560.136.4.1 to 60.136.4.12660.136.4.127126
1060.136.4.128/2560.136.4.129 to 60.136.4.25460.136.4.255126
1160.136.5.0/2560.136.5.1 to 60.136.5.12660.136.5.127126
1260.136.5.128/2560.136.5.129 to 60.136.5.25460.136.5.255126
1360.136.6.0/2560.136.6.1 to 60.136.6.12660.136.6.127126
1460.136.6.128/2560.136.6.129 to 60.136.6.25460.136.6.255126
1560.136.7.0/2560.136.7.1 to 60.136.7.12660.136.7.127126
1660.136.7.128/2560.136.7.129 to 60.136.7.25460.136.7.255126
1760.136.8.0/2560.136.8.1 to 60.136.8.12660.136.8.127126
1860.136.8.128/2560.136.8.129 to 60.136.8.25460.136.8.255126
1960.136.9.0/2560.136.9.1 to 60.136.9.12660.136.9.127126
2060.136.9.128/2560.136.9.129 to 60.136.9.25460.136.9.255126
2160.136.10.0/2560.136.10.1 to 60.136.10.12660.136.10.127126
2260.136.10.128/2560.136.10.129 to 60.136.10.25460.136.10.255126
2360.136.11.0/2560.136.11.1 to 60.136.11.12660.136.11.127126
2460.136.11.128/2560.136.11.129 to 60.136.11.25460.136.11.255126
2560.136.12.0/2560.136.12.1 to 60.136.12.12660.136.12.127126
2660.136.12.128/2560.136.12.129 to 60.136.12.25460.136.12.255126
2760.136.13.0/2560.136.13.1 to 60.136.13.12660.136.13.127126
2860.136.13.128/2560.136.13.129 to 60.136.13.25460.136.13.255126
2960.136.14.0/2560.136.14.1 to 60.136.14.12660.136.14.127126
3060.136.14.128/2560.136.14.129 to 60.136.14.25460.136.14.255126
3160.136.15.0/2560.136.15.1 to 60.136.15.12660.136.15.127126
3260.136.15.128/2560.136.15.129 to 60.136.15.25460.136.15.255126
3360.136.16.0/2560.136.16.1 to 60.136.16.12660.136.16.127126
3460.136.16.128/2560.136.16.129 to 60.136.16.25460.136.16.255126
3560.136.17.0/2560.136.17.1 to 60.136.17.12660.136.17.127126
3660.136.17.128/2560.136.17.129 to 60.136.17.25460.136.17.255126
3760.136.18.0/2560.136.18.1 to 60.136.18.12660.136.18.127126
3860.136.18.128/2560.136.18.129 to 60.136.18.25460.136.18.255126
3960.136.19.0/2560.136.19.1 to 60.136.19.12660.136.19.127126
4060.136.19.128/2560.136.19.129 to 60.136.19.25460.136.19.255126
4160.136.20.0/2560.136.20.1 to 60.136.20.12660.136.20.127126
4260.136.20.128/2560.136.20.129 to 60.136.20.25460.136.20.255126
4360.136.21.0/2560.136.21.1 to 60.136.21.12660.136.21.127126
4460.136.21.128/2560.136.21.129 to 60.136.21.25460.136.21.255126
4560.136.22.0/2560.136.22.1 to 60.136.22.12660.136.22.127126
4660.136.22.128/2560.136.22.129 to 60.136.22.25460.136.22.255126
4760.136.23.0/2560.136.23.1 to 60.136.23.12660.136.23.127126
4860.136.23.128/2560.136.23.129 to 60.136.23.25460.136.23.255126
4960.136.24.0/2560.136.24.1 to 60.136.24.12660.136.24.127126
5060.136.24.128/2560.136.24.129 to 60.136.24.25460.136.24.255126
5160.136.25.0/2560.136.25.1 to 60.136.25.12660.136.25.127126
5260.136.25.128/2560.136.25.129 to 60.136.25.25460.136.25.255126
5360.136.26.0/2560.136.26.1 to 60.136.26.12660.136.26.127126
5460.136.26.128/2560.136.26.129 to 60.136.26.25460.136.26.255126
5560.136.27.0/2560.136.27.1 to 60.136.27.12660.136.27.127126
5660.136.27.128/2560.136.27.129 to 60.136.27.25460.136.27.255126
5760.136.28.0/2560.136.28.1 to 60.136.28.12660.136.28.127126
5860.136.28.128/2560.136.28.129 to 60.136.28.25460.136.28.255126
5960.136.29.0/2560.136.29.1 to 60.136.29.12660.136.29.127126
6060.136.29.128/2560.136.29.129 to 60.136.29.25460.136.29.255126
6160.136.30.0/2560.136.30.1 to 60.136.30.12660.136.30.127126
6260.136.30.128/2560.136.30.129 to 60.136.30.25460.136.30.255126
6360.136.31.0/2560.136.31.1 to 60.136.31.12660.136.31.127126
6460.136.31.128/2560.136.31.129 to 60.136.31.25460.136.31.255126
6560.136.32.0/2560.136.32.1 to 60.136.32.12660.136.32.127126
6660.136.32.128/2560.136.32.129 to 60.136.32.25460.136.32.255126
6760.136.33.0/2560.136.33.1 to 60.136.33.12660.136.33.127126
6860.136.33.128/2560.136.33.129 to 60.136.33.25460.136.33.255126
6960.136.34.0/2560.136.34.1 to 60.136.34.12660.136.34.127126
7060.136.34.128/2560.136.34.129 to 60.136.34.25460.136.34.255126
7160.136.35.0/2560.136.35.1 to 60.136.35.12660.136.35.127126
7260.136.35.128/2560.136.35.129 to 60.136.35.25460.136.35.255126
7360.136.36.0/2560.136.36.1 to 60.136.36.12660.136.36.127126
7460.136.36.128/2560.136.36.129 to 60.136.36.25460.136.36.255126
7560.136.37.0/2560.136.37.1 to 60.136.37.12660.136.37.127126
7660.136.37.128/2560.136.37.129 to 60.136.37.25460.136.37.255126
7760.136.38.0/2560.136.38.1 to 60.136.38.12660.136.38.127126
7860.136.38.128/2560.136.38.129 to 60.136.38.25460.136.38.255126
7960.136.39.0/2560.136.39.1 to 60.136.39.12660.136.39.127126
8060.136.39.128/2560.136.39.129 to 60.136.39.25460.136.39.255126
8160.136.40.0/2560.136.40.1 to 60.136.40.12660.136.40.127126
8260.136.40.128/2560.136.40.129 to 60.136.40.25460.136.40.255126
8360.136.41.0/2560.136.41.1 to 60.136.41.12660.136.41.127126
8460.136.41.128/2560.136.41.129 to 60.136.41.25460.136.41.255126
8560.136.42.0/2560.136.42.1 to 60.136.42.12660.136.42.127126
8660.136.42.128/2560.136.42.129 to 60.136.42.25460.136.42.255126
8760.136.43.0/2560.136.43.1 to 60.136.43.12660.136.43.127126
8860.136.43.128/2560.136.43.129 to 60.136.43.25460.136.43.255126
8960.136.44.0/2560.136.44.1 to 60.136.44.12660.136.44.127126
9060.136.44.128/2560.136.44.129 to 60.136.44.25460.136.44.255126
9160.136.45.0/2560.136.45.1 to 60.136.45.12660.136.45.127126
9260.136.45.128/2560.136.45.129 to 60.136.45.25460.136.45.255126
9360.136.46.0/2560.136.46.1 to 60.136.46.12660.136.46.127126
9460.136.46.128/2560.136.46.129 to 60.136.46.25460.136.46.255126
9560.136.47.0/2560.136.47.1 to 60.136.47.12660.136.47.127126
9660.136.47.128/2560.136.47.129 to 60.136.47.25460.136.47.255126
9760.136.48.0/2560.136.48.1 to 60.136.48.12660.136.48.127126
9860.136.48.128/2560.136.48.129 to 60.136.48.25460.136.48.255126
9960.136.49.0/2560.136.49.1 to 60.136.49.12660.136.49.127126
10060.136.49.128/2560.136.49.129 to 60.136.49.25460.136.49.255126
10160.136.50.0/2560.136.50.1 to 60.136.50.12660.136.50.127126
10260.136.50.128/2560.136.50.129 to 60.136.50.25460.136.50.255126
10360.136.51.0/2560.136.51.1 to 60.136.51.12660.136.51.127126
10460.136.51.128/2560.136.51.129 to 60.136.51.25460.136.51.255126
10560.136.52.0/2560.136.52.1 to 60.136.52.12660.136.52.127126
10660.136.52.128/2560.136.52.129 to 60.136.52.25460.136.52.255126
10760.136.53.0/2560.136.53.1 to 60.136.53.12660.136.53.127126
10860.136.53.128/2560.136.53.129 to 60.136.53.25460.136.53.255126
10960.136.54.0/2560.136.54.1 to 60.136.54.12660.136.54.127126
11060.136.54.128/2560.136.54.129 to 60.136.54.25460.136.54.255126
11160.136.55.0/2560.136.55.1 to 60.136.55.12660.136.55.127126
11260.136.55.128/2560.136.55.129 to 60.136.55.25460.136.55.255126
11360.136.56.0/2560.136.56.1 to 60.136.56.12660.136.56.127126
11460.136.56.128/2560.136.56.129 to 60.136.56.25460.136.56.255126
11560.136.57.0/2560.136.57.1 to 60.136.57.12660.136.57.127126
11660.136.57.128/2560.136.57.129 to 60.136.57.25460.136.57.255126
11760.136.58.0/2560.136.58.1 to 60.136.58.12660.136.58.127126
11860.136.58.128/2560.136.58.129 to 60.136.58.25460.136.58.255126
11960.136.59.0/2560.136.59.1 to 60.136.59.12660.136.59.127126
12060.136.59.128/2560.136.59.129 to 60.136.59.25460.136.59.255126
12160.136.60.0/2560.136.60.1 to 60.136.60.12660.136.60.127126
12260.136.60.128/2560.136.60.129 to 60.136.60.25460.136.60.255126
12360.136.61.0/2560.136.61.1 to 60.136.61.12660.136.61.127126
12460.136.61.128/2560.136.61.129 to 60.136.61.25460.136.61.255126
12560.136.62.0/2560.136.62.1 to 60.136.62.12660.136.62.127126
12660.136.62.128/2560.136.62.129 to 60.136.62.25460.136.62.255126
12760.136.63.0/2560.136.63.1 to 60.136.63.12660.136.63.127126
12860.136.63.128/2560.136.63.129 to 60.136.63.25460.136.63.255126
12960.136.64.0/2560.136.64.1 to 60.136.64.12660.136.64.127126
13060.136.64.128/2560.136.64.129 to 60.136.64.25460.136.64.255126
13160.136.65.0/2560.136.65.1 to 60.136.65.12660.136.65.127126
13260.136.65.128/2560.136.65.129 to 60.136.65.25460.136.65.255126
13360.136.66.0/2560.136.66.1 to 60.136.66.12660.136.66.127126
13460.136.66.128/2560.136.66.129 to 60.136.66.25460.136.66.255126
13560.136.67.0/2560.136.67.1 to 60.136.67.12660.136.67.127126
13660.136.67.128/2560.136.67.129 to 60.136.67.25460.136.67.255126
13760.136.68.0/2560.136.68.1 to 60.136.68.12660.136.68.127126
13860.136.68.128/2560.136.68.129 to 60.136.68.25460.136.68.255126
13960.136.69.0/2560.136.69.1 to 60.136.69.12660.136.69.127126
14060.136.69.128/2560.136.69.129 to 60.136.69.25460.136.69.255126
14160.136.70.0/2560.136.70.1 to 60.136.70.12660.136.70.127126
14260.136.70.128/2560.136.70.129 to 60.136.70.25460.136.70.255126
14360.136.71.0/2560.136.71.1 to 60.136.71.12660.136.71.127126
14460.136.71.128/2560.136.71.129 to 60.136.71.25460.136.71.255126
14560.136.72.0/2560.136.72.1 to 60.136.72.12660.136.72.127126
14660.136.72.128/2560.136.72.129 to 60.136.72.25460.136.72.255126
14760.136.73.0/2560.136.73.1 to 60.136.73.12660.136.73.127126
14860.136.73.128/2560.136.73.129 to 60.136.73.25460.136.73.255126
14960.136.74.0/2560.136.74.1 to 60.136.74.12660.136.74.127126
15060.136.74.128/2560.136.74.129 to 60.136.74.25460.136.74.255126
15160.136.75.0/2560.136.75.1 to 60.136.75.12660.136.75.127126
15260.136.75.128/2560.136.75.129 to 60.136.75.25460.136.75.255126
15360.136.76.0/2560.136.76.1 to 60.136.76.12660.136.76.127126
15460.136.76.128/2560.136.76.129 to 60.136.76.25460.136.76.255126
15560.136.77.0/2560.136.77.1 to 60.136.77.12660.136.77.127126
15660.136.77.128/2560.136.77.129 to 60.136.77.25460.136.77.255126
15760.136.78.0/2560.136.78.1 to 60.136.78.12660.136.78.127126
15860.136.78.128/2560.136.78.129 to 60.136.78.25460.136.78.255126
15960.136.79.0/2560.136.79.1 to 60.136.79.12660.136.79.127126
16060.136.79.128/2560.136.79.129 to 60.136.79.25460.136.79.255126
16160.136.80.0/2560.136.80.1 to 60.136.80.12660.136.80.127126
16260.136.80.128/2560.136.80.129 to 60.136.80.25460.136.80.255126
16360.136.81.0/2560.136.81.1 to 60.136.81.12660.136.81.127126
16460.136.81.128/2560.136.81.129 to 60.136.81.25460.136.81.255126
16560.136.82.0/2560.136.82.1 to 60.136.82.12660.136.82.127126
16660.136.82.128/2560.136.82.129 to 60.136.82.25460.136.82.255126
16760.136.83.0/2560.136.83.1 to 60.136.83.12660.136.83.127126
16860.136.83.128/2560.136.83.129 to 60.136.83.25460.136.83.255126
16960.136.84.0/2560.136.84.1 to 60.136.84.12660.136.84.127126
17060.136.84.128/2560.136.84.129 to 60.136.84.25460.136.84.255126
17160.136.85.0/2560.136.85.1 to 60.136.85.12660.136.85.127126
17260.136.85.128/2560.136.85.129 to 60.136.85.25460.136.85.255126
17360.136.86.0/2560.136.86.1 to 60.136.86.12660.136.86.127126
17460.136.86.128/2560.136.86.129 to 60.136.86.25460.136.86.255126
17560.136.87.0/2560.136.87.1 to 60.136.87.12660.136.87.127126
17660.136.87.128/2560.136.87.129 to 60.136.87.25460.136.87.255126
17760.136.88.0/2560.136.88.1 to 60.136.88.12660.136.88.127126
17860.136.88.128/2560.136.88.129 to 60.136.88.25460.136.88.255126
17960.136.89.0/2560.136.89.1 to 60.136.89.12660.136.89.127126
18060.136.89.128/2560.136.89.129 to 60.136.89.25460.136.89.255126
18160.136.90.0/2560.136.90.1 to 60.136.90.12660.136.90.127126
18260.136.90.128/2560.136.90.129 to 60.136.90.25460.136.90.255126
18360.136.91.0/2560.136.91.1 to 60.136.91.12660.136.91.127126
18460.136.91.128/2560.136.91.129 to 60.136.91.25460.136.91.255126
18560.136.92.0/2560.136.92.1 to 60.136.92.12660.136.92.127126
18660.136.92.128/2560.136.92.129 to 60.136.92.25460.136.92.255126
18760.136.93.0/2560.136.93.1 to 60.136.93.12660.136.93.127126
18860.136.93.128/2560.136.93.129 to 60.136.93.25460.136.93.255126
18960.136.94.0/2560.136.94.1 to 60.136.94.12660.136.94.127126
19060.136.94.128/2560.136.94.129 to 60.136.94.25460.136.94.255126
19160.136.95.0/2560.136.95.1 to 60.136.95.12660.136.95.127126
19260.136.95.128/2560.136.95.129 to 60.136.95.25460.136.95.255126
19360.136.96.0/2560.136.96.1 to 60.136.96.12660.136.96.127126
19460.136.96.128/2560.136.96.129 to 60.136.96.25460.136.96.255126
19560.136.97.0/2560.136.97.1 to 60.136.97.12660.136.97.127126
19660.136.97.128/2560.136.97.129 to 60.136.97.25460.136.97.255126
19760.136.98.0/2560.136.98.1 to 60.136.98.12660.136.98.127126
19860.136.98.128/2560.136.98.129 to 60.136.98.25460.136.98.255126
19960.136.99.0/2560.136.99.1 to 60.136.99.12660.136.99.127126
20060.136.99.128/2560.136.99.129 to 60.136.99.25460.136.99.255126
20160.136.100.0/2560.136.100.1 to 60.136.100.12660.136.100.127126
20260.136.100.128/2560.136.100.129 to 60.136.100.25460.136.100.255126
20360.136.101.0/2560.136.101.1 to 60.136.101.12660.136.101.127126
20460.136.101.128/2560.136.101.129 to 60.136.101.25460.136.101.255126
20560.136.102.0/2560.136.102.1 to 60.136.102.12660.136.102.127126
20660.136.102.128/2560.136.102.129 to 60.136.102.25460.136.102.255126
20760.136.103.0/2560.136.103.1 to 60.136.103.12660.136.103.127126
20860.136.103.128/2560.136.103.129 to 60.136.103.25460.136.103.255126
20960.136.104.0/2560.136.104.1 to 60.136.104.12660.136.104.127126
21060.136.104.128/2560.136.104.129 to 60.136.104.25460.136.104.255126
21160.136.105.0/2560.136.105.1 to 60.136.105.12660.136.105.127126
21260.136.105.128/2560.136.105.129 to 60.136.105.25460.136.105.255126
21360.136.106.0/2560.136.106.1 to 60.136.106.12660.136.106.127126
21460.136.106.128/2560.136.106.129 to 60.136.106.25460.136.106.255126
21560.136.107.0/2560.136.107.1 to 60.136.107.12660.136.107.127126
21660.136.107.128/2560.136.107.129 to 60.136.107.25460.136.107.255126
21760.136.108.0/2560.136.108.1 to 60.136.108.12660.136.108.127126
21860.136.108.128/2560.136.108.129 to 60.136.108.25460.136.108.255126
21960.136.109.0/2560.136.109.1 to 60.136.109.12660.136.109.127126
22060.136.109.128/2560.136.109.129 to 60.136.109.25460.136.109.255126
22160.136.110.0/2560.136.110.1 to 60.136.110.12660.136.110.127126
22260.136.110.128/2560.136.110.129 to 60.136.110.25460.136.110.255126
22360.136.111.0/2560.136.111.1 to 60.136.111.12660.136.111.127126
22460.136.111.128/2560.136.111.129 to 60.136.111.25460.136.111.255126
22560.136.112.0/2560.136.112.1 to 60.136.112.12660.136.112.127126
22660.136.112.128/2560.136.112.129 to 60.136.112.25460.136.112.255126
22760.136.113.0/2560.136.113.1 to 60.136.113.12660.136.113.127126
22860.136.113.128/2560.136.113.129 to 60.136.113.25460.136.113.255126
22960.136.114.0/2560.136.114.1 to 60.136.114.12660.136.114.127126
23060.136.114.128/2560.136.114.129 to 60.136.114.25460.136.114.255126
23160.136.115.0/2560.136.115.1 to 60.136.115.12660.136.115.127126
23260.136.115.128/2560.136.115.129 to 60.136.115.25460.136.115.255126
23360.136.116.0/2560.136.116.1 to 60.136.116.12660.136.116.127126
23460.136.116.128/2560.136.116.129 to 60.136.116.25460.136.116.255126
23560.136.117.0/2560.136.117.1 to 60.136.117.12660.136.117.127126
23660.136.117.128/2560.136.117.129 to 60.136.117.25460.136.117.255126
23760.136.118.0/2560.136.118.1 to 60.136.118.12660.136.118.127126
23860.136.118.128/2560.136.118.129 to 60.136.118.25460.136.118.255126
23960.136.119.0/2560.136.119.1 to 60.136.119.12660.136.119.127126
24060.136.119.128/2560.136.119.129 to 60.136.119.25460.136.119.255126
24160.136.120.0/2560.136.120.1 to 60.136.120.12660.136.120.127126
24260.136.120.128/2560.136.120.129 to 60.136.120.25460.136.120.255126
24360.136.121.0/2560.136.121.1 to 60.136.121.12660.136.121.127126
24460.136.121.128/2560.136.121.129 to 60.136.121.25460.136.121.255126
24560.136.122.0/2560.136.122.1 to 60.136.122.12660.136.122.127126
24660.136.122.128/2560.136.122.129 to 60.136.122.25460.136.122.255126
24760.136.123.0/2560.136.123.1 to 60.136.123.12660.136.123.127126
24860.136.123.128/2560.136.123.129 to 60.136.123.25460.136.123.255126
24960.136.124.0/2560.136.124.1 to 60.136.124.12660.136.124.127126
25060.136.124.128/2560.136.124.129 to 60.136.124.25460.136.124.255126
25160.136.125.0/2560.136.125.1 to 60.136.125.12660.136.125.127126
25260.136.125.128/2560.136.125.129 to 60.136.125.25460.136.125.255126
25360.136.126.0/2560.136.126.1 to 60.136.126.12660.136.126.127126
25460.136.126.128/2560.136.126.129 to 60.136.126.25460.136.126.255126
25560.136.127.0/2560.136.127.1 to 60.136.127.12660.136.127.127126
25660.136.127.128/2560.136.127.129 to 60.136.127.25460.136.127.255126

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.