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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.

Network82.2.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
82.2.0.0
Broadcast address
82.2.127.255
First usable
82.2.0.1
Last usable
82.2.127.254
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 52020000 · Integer 1375862784 to 1375895551
Reverse DNS zones
0.2.82.in-addr.arpa
1.2.82.in-addr.arpa
2.2.82.in-addr.arpa
3.2.82.in-addr.arpa
4.2.82.in-addr.arpa
5.2.82.in-addr.arpa
6.2.82.in-addr.arpa
7.2.82.in-addr.arpa
8.2.82.in-addr.arpa
9.2.82.in-addr.arpa
10.2.82.in-addr.arpa
11.2.82.in-addr.arpa
12.2.82.in-addr.arpa
13.2.82.in-addr.arpa
14.2.82.in-addr.arpa
15.2.82.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
Address01010010.00000010.00000000.0000000082.2.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network01010010.00000010.00000000.0000000082.2.0.0
Broadcast01010010.00000010.01111111.1111111182.2.127.255
Split into smaller subnets/25

82.2.0.0/17 makes 256 subnets of /25.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
182.2.0.0/2582.2.0.1 to 82.2.0.12682.2.0.127126
282.2.0.128/2582.2.0.129 to 82.2.0.25482.2.0.255126
382.2.1.0/2582.2.1.1 to 82.2.1.12682.2.1.127126
482.2.1.128/2582.2.1.129 to 82.2.1.25482.2.1.255126
582.2.2.0/2582.2.2.1 to 82.2.2.12682.2.2.127126
682.2.2.128/2582.2.2.129 to 82.2.2.25482.2.2.255126
782.2.3.0/2582.2.3.1 to 82.2.3.12682.2.3.127126
882.2.3.128/2582.2.3.129 to 82.2.3.25482.2.3.255126
982.2.4.0/2582.2.4.1 to 82.2.4.12682.2.4.127126
1082.2.4.128/2582.2.4.129 to 82.2.4.25482.2.4.255126
1182.2.5.0/2582.2.5.1 to 82.2.5.12682.2.5.127126
1282.2.5.128/2582.2.5.129 to 82.2.5.25482.2.5.255126
1382.2.6.0/2582.2.6.1 to 82.2.6.12682.2.6.127126
1482.2.6.128/2582.2.6.129 to 82.2.6.25482.2.6.255126
1582.2.7.0/2582.2.7.1 to 82.2.7.12682.2.7.127126
1682.2.7.128/2582.2.7.129 to 82.2.7.25482.2.7.255126
1782.2.8.0/2582.2.8.1 to 82.2.8.12682.2.8.127126
1882.2.8.128/2582.2.8.129 to 82.2.8.25482.2.8.255126
1982.2.9.0/2582.2.9.1 to 82.2.9.12682.2.9.127126
2082.2.9.128/2582.2.9.129 to 82.2.9.25482.2.9.255126
2182.2.10.0/2582.2.10.1 to 82.2.10.12682.2.10.127126
2282.2.10.128/2582.2.10.129 to 82.2.10.25482.2.10.255126
2382.2.11.0/2582.2.11.1 to 82.2.11.12682.2.11.127126
2482.2.11.128/2582.2.11.129 to 82.2.11.25482.2.11.255126
2582.2.12.0/2582.2.12.1 to 82.2.12.12682.2.12.127126
2682.2.12.128/2582.2.12.129 to 82.2.12.25482.2.12.255126
2782.2.13.0/2582.2.13.1 to 82.2.13.12682.2.13.127126
2882.2.13.128/2582.2.13.129 to 82.2.13.25482.2.13.255126
2982.2.14.0/2582.2.14.1 to 82.2.14.12682.2.14.127126
3082.2.14.128/2582.2.14.129 to 82.2.14.25482.2.14.255126
3182.2.15.0/2582.2.15.1 to 82.2.15.12682.2.15.127126
3282.2.15.128/2582.2.15.129 to 82.2.15.25482.2.15.255126
3382.2.16.0/2582.2.16.1 to 82.2.16.12682.2.16.127126
3482.2.16.128/2582.2.16.129 to 82.2.16.25482.2.16.255126
3582.2.17.0/2582.2.17.1 to 82.2.17.12682.2.17.127126
3682.2.17.128/2582.2.17.129 to 82.2.17.25482.2.17.255126
3782.2.18.0/2582.2.18.1 to 82.2.18.12682.2.18.127126
3882.2.18.128/2582.2.18.129 to 82.2.18.25482.2.18.255126
3982.2.19.0/2582.2.19.1 to 82.2.19.12682.2.19.127126
4082.2.19.128/2582.2.19.129 to 82.2.19.25482.2.19.255126
4182.2.20.0/2582.2.20.1 to 82.2.20.12682.2.20.127126
4282.2.20.128/2582.2.20.129 to 82.2.20.25482.2.20.255126
4382.2.21.0/2582.2.21.1 to 82.2.21.12682.2.21.127126
4482.2.21.128/2582.2.21.129 to 82.2.21.25482.2.21.255126
4582.2.22.0/2582.2.22.1 to 82.2.22.12682.2.22.127126
4682.2.22.128/2582.2.22.129 to 82.2.22.25482.2.22.255126
4782.2.23.0/2582.2.23.1 to 82.2.23.12682.2.23.127126
4882.2.23.128/2582.2.23.129 to 82.2.23.25482.2.23.255126
4982.2.24.0/2582.2.24.1 to 82.2.24.12682.2.24.127126
5082.2.24.128/2582.2.24.129 to 82.2.24.25482.2.24.255126
5182.2.25.0/2582.2.25.1 to 82.2.25.12682.2.25.127126
5282.2.25.128/2582.2.25.129 to 82.2.25.25482.2.25.255126
5382.2.26.0/2582.2.26.1 to 82.2.26.12682.2.26.127126
5482.2.26.128/2582.2.26.129 to 82.2.26.25482.2.26.255126
5582.2.27.0/2582.2.27.1 to 82.2.27.12682.2.27.127126
5682.2.27.128/2582.2.27.129 to 82.2.27.25482.2.27.255126
5782.2.28.0/2582.2.28.1 to 82.2.28.12682.2.28.127126
5882.2.28.128/2582.2.28.129 to 82.2.28.25482.2.28.255126
5982.2.29.0/2582.2.29.1 to 82.2.29.12682.2.29.127126
6082.2.29.128/2582.2.29.129 to 82.2.29.25482.2.29.255126
6182.2.30.0/2582.2.30.1 to 82.2.30.12682.2.30.127126
6282.2.30.128/2582.2.30.129 to 82.2.30.25482.2.30.255126
6382.2.31.0/2582.2.31.1 to 82.2.31.12682.2.31.127126
6482.2.31.128/2582.2.31.129 to 82.2.31.25482.2.31.255126
6582.2.32.0/2582.2.32.1 to 82.2.32.12682.2.32.127126
6682.2.32.128/2582.2.32.129 to 82.2.32.25482.2.32.255126
6782.2.33.0/2582.2.33.1 to 82.2.33.12682.2.33.127126
6882.2.33.128/2582.2.33.129 to 82.2.33.25482.2.33.255126
6982.2.34.0/2582.2.34.1 to 82.2.34.12682.2.34.127126
7082.2.34.128/2582.2.34.129 to 82.2.34.25482.2.34.255126
7182.2.35.0/2582.2.35.1 to 82.2.35.12682.2.35.127126
7282.2.35.128/2582.2.35.129 to 82.2.35.25482.2.35.255126
7382.2.36.0/2582.2.36.1 to 82.2.36.12682.2.36.127126
7482.2.36.128/2582.2.36.129 to 82.2.36.25482.2.36.255126
7582.2.37.0/2582.2.37.1 to 82.2.37.12682.2.37.127126
7682.2.37.128/2582.2.37.129 to 82.2.37.25482.2.37.255126
7782.2.38.0/2582.2.38.1 to 82.2.38.12682.2.38.127126
7882.2.38.128/2582.2.38.129 to 82.2.38.25482.2.38.255126
7982.2.39.0/2582.2.39.1 to 82.2.39.12682.2.39.127126
8082.2.39.128/2582.2.39.129 to 82.2.39.25482.2.39.255126
8182.2.40.0/2582.2.40.1 to 82.2.40.12682.2.40.127126
8282.2.40.128/2582.2.40.129 to 82.2.40.25482.2.40.255126
8382.2.41.0/2582.2.41.1 to 82.2.41.12682.2.41.127126
8482.2.41.128/2582.2.41.129 to 82.2.41.25482.2.41.255126
8582.2.42.0/2582.2.42.1 to 82.2.42.12682.2.42.127126
8682.2.42.128/2582.2.42.129 to 82.2.42.25482.2.42.255126
8782.2.43.0/2582.2.43.1 to 82.2.43.12682.2.43.127126
8882.2.43.128/2582.2.43.129 to 82.2.43.25482.2.43.255126
8982.2.44.0/2582.2.44.1 to 82.2.44.12682.2.44.127126
9082.2.44.128/2582.2.44.129 to 82.2.44.25482.2.44.255126
9182.2.45.0/2582.2.45.1 to 82.2.45.12682.2.45.127126
9282.2.45.128/2582.2.45.129 to 82.2.45.25482.2.45.255126
9382.2.46.0/2582.2.46.1 to 82.2.46.12682.2.46.127126
9482.2.46.128/2582.2.46.129 to 82.2.46.25482.2.46.255126
9582.2.47.0/2582.2.47.1 to 82.2.47.12682.2.47.127126
9682.2.47.128/2582.2.47.129 to 82.2.47.25482.2.47.255126
9782.2.48.0/2582.2.48.1 to 82.2.48.12682.2.48.127126
9882.2.48.128/2582.2.48.129 to 82.2.48.25482.2.48.255126
9982.2.49.0/2582.2.49.1 to 82.2.49.12682.2.49.127126
10082.2.49.128/2582.2.49.129 to 82.2.49.25482.2.49.255126
10182.2.50.0/2582.2.50.1 to 82.2.50.12682.2.50.127126
10282.2.50.128/2582.2.50.129 to 82.2.50.25482.2.50.255126
10382.2.51.0/2582.2.51.1 to 82.2.51.12682.2.51.127126
10482.2.51.128/2582.2.51.129 to 82.2.51.25482.2.51.255126
10582.2.52.0/2582.2.52.1 to 82.2.52.12682.2.52.127126
10682.2.52.128/2582.2.52.129 to 82.2.52.25482.2.52.255126
10782.2.53.0/2582.2.53.1 to 82.2.53.12682.2.53.127126
10882.2.53.128/2582.2.53.129 to 82.2.53.25482.2.53.255126
10982.2.54.0/2582.2.54.1 to 82.2.54.12682.2.54.127126
11082.2.54.128/2582.2.54.129 to 82.2.54.25482.2.54.255126
11182.2.55.0/2582.2.55.1 to 82.2.55.12682.2.55.127126
11282.2.55.128/2582.2.55.129 to 82.2.55.25482.2.55.255126
11382.2.56.0/2582.2.56.1 to 82.2.56.12682.2.56.127126
11482.2.56.128/2582.2.56.129 to 82.2.56.25482.2.56.255126
11582.2.57.0/2582.2.57.1 to 82.2.57.12682.2.57.127126
11682.2.57.128/2582.2.57.129 to 82.2.57.25482.2.57.255126
11782.2.58.0/2582.2.58.1 to 82.2.58.12682.2.58.127126
11882.2.58.128/2582.2.58.129 to 82.2.58.25482.2.58.255126
11982.2.59.0/2582.2.59.1 to 82.2.59.12682.2.59.127126
12082.2.59.128/2582.2.59.129 to 82.2.59.25482.2.59.255126
12182.2.60.0/2582.2.60.1 to 82.2.60.12682.2.60.127126
12282.2.60.128/2582.2.60.129 to 82.2.60.25482.2.60.255126
12382.2.61.0/2582.2.61.1 to 82.2.61.12682.2.61.127126
12482.2.61.128/2582.2.61.129 to 82.2.61.25482.2.61.255126
12582.2.62.0/2582.2.62.1 to 82.2.62.12682.2.62.127126
12682.2.62.128/2582.2.62.129 to 82.2.62.25482.2.62.255126
12782.2.63.0/2582.2.63.1 to 82.2.63.12682.2.63.127126
12882.2.63.128/2582.2.63.129 to 82.2.63.25482.2.63.255126
12982.2.64.0/2582.2.64.1 to 82.2.64.12682.2.64.127126
13082.2.64.128/2582.2.64.129 to 82.2.64.25482.2.64.255126
13182.2.65.0/2582.2.65.1 to 82.2.65.12682.2.65.127126
13282.2.65.128/2582.2.65.129 to 82.2.65.25482.2.65.255126
13382.2.66.0/2582.2.66.1 to 82.2.66.12682.2.66.127126
13482.2.66.128/2582.2.66.129 to 82.2.66.25482.2.66.255126
13582.2.67.0/2582.2.67.1 to 82.2.67.12682.2.67.127126
13682.2.67.128/2582.2.67.129 to 82.2.67.25482.2.67.255126
13782.2.68.0/2582.2.68.1 to 82.2.68.12682.2.68.127126
13882.2.68.128/2582.2.68.129 to 82.2.68.25482.2.68.255126
13982.2.69.0/2582.2.69.1 to 82.2.69.12682.2.69.127126
14082.2.69.128/2582.2.69.129 to 82.2.69.25482.2.69.255126
14182.2.70.0/2582.2.70.1 to 82.2.70.12682.2.70.127126
14282.2.70.128/2582.2.70.129 to 82.2.70.25482.2.70.255126
14382.2.71.0/2582.2.71.1 to 82.2.71.12682.2.71.127126
14482.2.71.128/2582.2.71.129 to 82.2.71.25482.2.71.255126
14582.2.72.0/2582.2.72.1 to 82.2.72.12682.2.72.127126
14682.2.72.128/2582.2.72.129 to 82.2.72.25482.2.72.255126
14782.2.73.0/2582.2.73.1 to 82.2.73.12682.2.73.127126
14882.2.73.128/2582.2.73.129 to 82.2.73.25482.2.73.255126
14982.2.74.0/2582.2.74.1 to 82.2.74.12682.2.74.127126
15082.2.74.128/2582.2.74.129 to 82.2.74.25482.2.74.255126
15182.2.75.0/2582.2.75.1 to 82.2.75.12682.2.75.127126
15282.2.75.128/2582.2.75.129 to 82.2.75.25482.2.75.255126
15382.2.76.0/2582.2.76.1 to 82.2.76.12682.2.76.127126
15482.2.76.128/2582.2.76.129 to 82.2.76.25482.2.76.255126
15582.2.77.0/2582.2.77.1 to 82.2.77.12682.2.77.127126
15682.2.77.128/2582.2.77.129 to 82.2.77.25482.2.77.255126
15782.2.78.0/2582.2.78.1 to 82.2.78.12682.2.78.127126
15882.2.78.128/2582.2.78.129 to 82.2.78.25482.2.78.255126
15982.2.79.0/2582.2.79.1 to 82.2.79.12682.2.79.127126
16082.2.79.128/2582.2.79.129 to 82.2.79.25482.2.79.255126
16182.2.80.0/2582.2.80.1 to 82.2.80.12682.2.80.127126
16282.2.80.128/2582.2.80.129 to 82.2.80.25482.2.80.255126
16382.2.81.0/2582.2.81.1 to 82.2.81.12682.2.81.127126
16482.2.81.128/2582.2.81.129 to 82.2.81.25482.2.81.255126
16582.2.82.0/2582.2.82.1 to 82.2.82.12682.2.82.127126
16682.2.82.128/2582.2.82.129 to 82.2.82.25482.2.82.255126
16782.2.83.0/2582.2.83.1 to 82.2.83.12682.2.83.127126
16882.2.83.128/2582.2.83.129 to 82.2.83.25482.2.83.255126
16982.2.84.0/2582.2.84.1 to 82.2.84.12682.2.84.127126
17082.2.84.128/2582.2.84.129 to 82.2.84.25482.2.84.255126
17182.2.85.0/2582.2.85.1 to 82.2.85.12682.2.85.127126
17282.2.85.128/2582.2.85.129 to 82.2.85.25482.2.85.255126
17382.2.86.0/2582.2.86.1 to 82.2.86.12682.2.86.127126
17482.2.86.128/2582.2.86.129 to 82.2.86.25482.2.86.255126
17582.2.87.0/2582.2.87.1 to 82.2.87.12682.2.87.127126
17682.2.87.128/2582.2.87.129 to 82.2.87.25482.2.87.255126
17782.2.88.0/2582.2.88.1 to 82.2.88.12682.2.88.127126
17882.2.88.128/2582.2.88.129 to 82.2.88.25482.2.88.255126
17982.2.89.0/2582.2.89.1 to 82.2.89.12682.2.89.127126
18082.2.89.128/2582.2.89.129 to 82.2.89.25482.2.89.255126
18182.2.90.0/2582.2.90.1 to 82.2.90.12682.2.90.127126
18282.2.90.128/2582.2.90.129 to 82.2.90.25482.2.90.255126
18382.2.91.0/2582.2.91.1 to 82.2.91.12682.2.91.127126
18482.2.91.128/2582.2.91.129 to 82.2.91.25482.2.91.255126
18582.2.92.0/2582.2.92.1 to 82.2.92.12682.2.92.127126
18682.2.92.128/2582.2.92.129 to 82.2.92.25482.2.92.255126
18782.2.93.0/2582.2.93.1 to 82.2.93.12682.2.93.127126
18882.2.93.128/2582.2.93.129 to 82.2.93.25482.2.93.255126
18982.2.94.0/2582.2.94.1 to 82.2.94.12682.2.94.127126
19082.2.94.128/2582.2.94.129 to 82.2.94.25482.2.94.255126
19182.2.95.0/2582.2.95.1 to 82.2.95.12682.2.95.127126
19282.2.95.128/2582.2.95.129 to 82.2.95.25482.2.95.255126
19382.2.96.0/2582.2.96.1 to 82.2.96.12682.2.96.127126
19482.2.96.128/2582.2.96.129 to 82.2.96.25482.2.96.255126
19582.2.97.0/2582.2.97.1 to 82.2.97.12682.2.97.127126
19682.2.97.128/2582.2.97.129 to 82.2.97.25482.2.97.255126
19782.2.98.0/2582.2.98.1 to 82.2.98.12682.2.98.127126
19882.2.98.128/2582.2.98.129 to 82.2.98.25482.2.98.255126
19982.2.99.0/2582.2.99.1 to 82.2.99.12682.2.99.127126
20082.2.99.128/2582.2.99.129 to 82.2.99.25482.2.99.255126
20182.2.100.0/2582.2.100.1 to 82.2.100.12682.2.100.127126
20282.2.100.128/2582.2.100.129 to 82.2.100.25482.2.100.255126
20382.2.101.0/2582.2.101.1 to 82.2.101.12682.2.101.127126
20482.2.101.128/2582.2.101.129 to 82.2.101.25482.2.101.255126
20582.2.102.0/2582.2.102.1 to 82.2.102.12682.2.102.127126
20682.2.102.128/2582.2.102.129 to 82.2.102.25482.2.102.255126
20782.2.103.0/2582.2.103.1 to 82.2.103.12682.2.103.127126
20882.2.103.128/2582.2.103.129 to 82.2.103.25482.2.103.255126
20982.2.104.0/2582.2.104.1 to 82.2.104.12682.2.104.127126
21082.2.104.128/2582.2.104.129 to 82.2.104.25482.2.104.255126
21182.2.105.0/2582.2.105.1 to 82.2.105.12682.2.105.127126
21282.2.105.128/2582.2.105.129 to 82.2.105.25482.2.105.255126
21382.2.106.0/2582.2.106.1 to 82.2.106.12682.2.106.127126
21482.2.106.128/2582.2.106.129 to 82.2.106.25482.2.106.255126
21582.2.107.0/2582.2.107.1 to 82.2.107.12682.2.107.127126
21682.2.107.128/2582.2.107.129 to 82.2.107.25482.2.107.255126
21782.2.108.0/2582.2.108.1 to 82.2.108.12682.2.108.127126
21882.2.108.128/2582.2.108.129 to 82.2.108.25482.2.108.255126
21982.2.109.0/2582.2.109.1 to 82.2.109.12682.2.109.127126
22082.2.109.128/2582.2.109.129 to 82.2.109.25482.2.109.255126
22182.2.110.0/2582.2.110.1 to 82.2.110.12682.2.110.127126
22282.2.110.128/2582.2.110.129 to 82.2.110.25482.2.110.255126
22382.2.111.0/2582.2.111.1 to 82.2.111.12682.2.111.127126
22482.2.111.128/2582.2.111.129 to 82.2.111.25482.2.111.255126
22582.2.112.0/2582.2.112.1 to 82.2.112.12682.2.112.127126
22682.2.112.128/2582.2.112.129 to 82.2.112.25482.2.112.255126
22782.2.113.0/2582.2.113.1 to 82.2.113.12682.2.113.127126
22882.2.113.128/2582.2.113.129 to 82.2.113.25482.2.113.255126
22982.2.114.0/2582.2.114.1 to 82.2.114.12682.2.114.127126
23082.2.114.128/2582.2.114.129 to 82.2.114.25482.2.114.255126
23182.2.115.0/2582.2.115.1 to 82.2.115.12682.2.115.127126
23282.2.115.128/2582.2.115.129 to 82.2.115.25482.2.115.255126
23382.2.116.0/2582.2.116.1 to 82.2.116.12682.2.116.127126
23482.2.116.128/2582.2.116.129 to 82.2.116.25482.2.116.255126
23582.2.117.0/2582.2.117.1 to 82.2.117.12682.2.117.127126
23682.2.117.128/2582.2.117.129 to 82.2.117.25482.2.117.255126
23782.2.118.0/2582.2.118.1 to 82.2.118.12682.2.118.127126
23882.2.118.128/2582.2.118.129 to 82.2.118.25482.2.118.255126
23982.2.119.0/2582.2.119.1 to 82.2.119.12682.2.119.127126
24082.2.119.128/2582.2.119.129 to 82.2.119.25482.2.119.255126
24182.2.120.0/2582.2.120.1 to 82.2.120.12682.2.120.127126
24282.2.120.128/2582.2.120.129 to 82.2.120.25482.2.120.255126
24382.2.121.0/2582.2.121.1 to 82.2.121.12682.2.121.127126
24482.2.121.128/2582.2.121.129 to 82.2.121.25482.2.121.255126
24582.2.122.0/2582.2.122.1 to 82.2.122.12682.2.122.127126
24682.2.122.128/2582.2.122.129 to 82.2.122.25482.2.122.255126
24782.2.123.0/2582.2.123.1 to 82.2.123.12682.2.123.127126
24882.2.123.128/2582.2.123.129 to 82.2.123.25482.2.123.255126
24982.2.124.0/2582.2.124.1 to 82.2.124.12682.2.124.127126
25082.2.124.128/2582.2.124.129 to 82.2.124.25482.2.124.255126
25182.2.125.0/2582.2.125.1 to 82.2.125.12682.2.125.127126
25282.2.125.128/2582.2.125.129 to 82.2.125.25482.2.125.255126
25382.2.126.0/2582.2.126.1 to 82.2.126.12682.2.126.127126
25482.2.126.128/2582.2.126.129 to 82.2.126.25482.2.126.255126
25582.2.127.0/2582.2.127.1 to 82.2.127.12682.2.127.127126
25682.2.127.128/2582.2.127.129 to 82.2.127.25482.2.127.255126

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