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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.

Network75.80.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
75.80.0.0
Broadcast address
75.83.255.255
First usable
75.80.0.1
Last usable
75.83.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 4B500000 · Integer 1263534080 to 1263796223
Reverse DNS zones
80.75.in-addr.arpa
81.75.in-addr.arpa
82.75.in-addr.arpa
83.75.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01001011.01010000.00000000.0000000075.80.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01001011.01010000.00000000.0000000075.80.0.0
Broadcast01001011.01010011.11111111.1111111175.83.255.255
Split into smaller subnets/25
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

75.80.0.0/14 makes 2,048 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
175.80.0.0/2575.80.0.1 to 75.80.0.12675.80.0.127126
275.80.0.128/2575.80.0.129 to 75.80.0.25475.80.0.255126
375.80.1.0/2575.80.1.1 to 75.80.1.12675.80.1.127126
475.80.1.128/2575.80.1.129 to 75.80.1.25475.80.1.255126
575.80.2.0/2575.80.2.1 to 75.80.2.12675.80.2.127126
675.80.2.128/2575.80.2.129 to 75.80.2.25475.80.2.255126
775.80.3.0/2575.80.3.1 to 75.80.3.12675.80.3.127126
875.80.3.128/2575.80.3.129 to 75.80.3.25475.80.3.255126
975.80.4.0/2575.80.4.1 to 75.80.4.12675.80.4.127126
1075.80.4.128/2575.80.4.129 to 75.80.4.25475.80.4.255126
1175.80.5.0/2575.80.5.1 to 75.80.5.12675.80.5.127126
1275.80.5.128/2575.80.5.129 to 75.80.5.25475.80.5.255126
1375.80.6.0/2575.80.6.1 to 75.80.6.12675.80.6.127126
1475.80.6.128/2575.80.6.129 to 75.80.6.25475.80.6.255126
1575.80.7.0/2575.80.7.1 to 75.80.7.12675.80.7.127126
1675.80.7.128/2575.80.7.129 to 75.80.7.25475.80.7.255126
1775.80.8.0/2575.80.8.1 to 75.80.8.12675.80.8.127126
1875.80.8.128/2575.80.8.129 to 75.80.8.25475.80.8.255126
1975.80.9.0/2575.80.9.1 to 75.80.9.12675.80.9.127126
2075.80.9.128/2575.80.9.129 to 75.80.9.25475.80.9.255126
2175.80.10.0/2575.80.10.1 to 75.80.10.12675.80.10.127126
2275.80.10.128/2575.80.10.129 to 75.80.10.25475.80.10.255126
2375.80.11.0/2575.80.11.1 to 75.80.11.12675.80.11.127126
2475.80.11.128/2575.80.11.129 to 75.80.11.25475.80.11.255126
2575.80.12.0/2575.80.12.1 to 75.80.12.12675.80.12.127126
2675.80.12.128/2575.80.12.129 to 75.80.12.25475.80.12.255126
2775.80.13.0/2575.80.13.1 to 75.80.13.12675.80.13.127126
2875.80.13.128/2575.80.13.129 to 75.80.13.25475.80.13.255126
2975.80.14.0/2575.80.14.1 to 75.80.14.12675.80.14.127126
3075.80.14.128/2575.80.14.129 to 75.80.14.25475.80.14.255126
3175.80.15.0/2575.80.15.1 to 75.80.15.12675.80.15.127126
3275.80.15.128/2575.80.15.129 to 75.80.15.25475.80.15.255126
3375.80.16.0/2575.80.16.1 to 75.80.16.12675.80.16.127126
3475.80.16.128/2575.80.16.129 to 75.80.16.25475.80.16.255126
3575.80.17.0/2575.80.17.1 to 75.80.17.12675.80.17.127126
3675.80.17.128/2575.80.17.129 to 75.80.17.25475.80.17.255126
3775.80.18.0/2575.80.18.1 to 75.80.18.12675.80.18.127126
3875.80.18.128/2575.80.18.129 to 75.80.18.25475.80.18.255126
3975.80.19.0/2575.80.19.1 to 75.80.19.12675.80.19.127126
4075.80.19.128/2575.80.19.129 to 75.80.19.25475.80.19.255126
4175.80.20.0/2575.80.20.1 to 75.80.20.12675.80.20.127126
4275.80.20.128/2575.80.20.129 to 75.80.20.25475.80.20.255126
4375.80.21.0/2575.80.21.1 to 75.80.21.12675.80.21.127126
4475.80.21.128/2575.80.21.129 to 75.80.21.25475.80.21.255126
4575.80.22.0/2575.80.22.1 to 75.80.22.12675.80.22.127126
4675.80.22.128/2575.80.22.129 to 75.80.22.25475.80.22.255126
4775.80.23.0/2575.80.23.1 to 75.80.23.12675.80.23.127126
4875.80.23.128/2575.80.23.129 to 75.80.23.25475.80.23.255126
4975.80.24.0/2575.80.24.1 to 75.80.24.12675.80.24.127126
5075.80.24.128/2575.80.24.129 to 75.80.24.25475.80.24.255126
5175.80.25.0/2575.80.25.1 to 75.80.25.12675.80.25.127126
5275.80.25.128/2575.80.25.129 to 75.80.25.25475.80.25.255126
5375.80.26.0/2575.80.26.1 to 75.80.26.12675.80.26.127126
5475.80.26.128/2575.80.26.129 to 75.80.26.25475.80.26.255126
5575.80.27.0/2575.80.27.1 to 75.80.27.12675.80.27.127126
5675.80.27.128/2575.80.27.129 to 75.80.27.25475.80.27.255126
5775.80.28.0/2575.80.28.1 to 75.80.28.12675.80.28.127126
5875.80.28.128/2575.80.28.129 to 75.80.28.25475.80.28.255126
5975.80.29.0/2575.80.29.1 to 75.80.29.12675.80.29.127126
6075.80.29.128/2575.80.29.129 to 75.80.29.25475.80.29.255126
6175.80.30.0/2575.80.30.1 to 75.80.30.12675.80.30.127126
6275.80.30.128/2575.80.30.129 to 75.80.30.25475.80.30.255126
6375.80.31.0/2575.80.31.1 to 75.80.31.12675.80.31.127126
6475.80.31.128/2575.80.31.129 to 75.80.31.25475.80.31.255126
6575.80.32.0/2575.80.32.1 to 75.80.32.12675.80.32.127126
6675.80.32.128/2575.80.32.129 to 75.80.32.25475.80.32.255126
6775.80.33.0/2575.80.33.1 to 75.80.33.12675.80.33.127126
6875.80.33.128/2575.80.33.129 to 75.80.33.25475.80.33.255126
6975.80.34.0/2575.80.34.1 to 75.80.34.12675.80.34.127126
7075.80.34.128/2575.80.34.129 to 75.80.34.25475.80.34.255126
7175.80.35.0/2575.80.35.1 to 75.80.35.12675.80.35.127126
7275.80.35.128/2575.80.35.129 to 75.80.35.25475.80.35.255126
7375.80.36.0/2575.80.36.1 to 75.80.36.12675.80.36.127126
7475.80.36.128/2575.80.36.129 to 75.80.36.25475.80.36.255126
7575.80.37.0/2575.80.37.1 to 75.80.37.12675.80.37.127126
7675.80.37.128/2575.80.37.129 to 75.80.37.25475.80.37.255126
7775.80.38.0/2575.80.38.1 to 75.80.38.12675.80.38.127126
7875.80.38.128/2575.80.38.129 to 75.80.38.25475.80.38.255126
7975.80.39.0/2575.80.39.1 to 75.80.39.12675.80.39.127126
8075.80.39.128/2575.80.39.129 to 75.80.39.25475.80.39.255126
8175.80.40.0/2575.80.40.1 to 75.80.40.12675.80.40.127126
8275.80.40.128/2575.80.40.129 to 75.80.40.25475.80.40.255126
8375.80.41.0/2575.80.41.1 to 75.80.41.12675.80.41.127126
8475.80.41.128/2575.80.41.129 to 75.80.41.25475.80.41.255126
8575.80.42.0/2575.80.42.1 to 75.80.42.12675.80.42.127126
8675.80.42.128/2575.80.42.129 to 75.80.42.25475.80.42.255126
8775.80.43.0/2575.80.43.1 to 75.80.43.12675.80.43.127126
8875.80.43.128/2575.80.43.129 to 75.80.43.25475.80.43.255126
8975.80.44.0/2575.80.44.1 to 75.80.44.12675.80.44.127126
9075.80.44.128/2575.80.44.129 to 75.80.44.25475.80.44.255126
9175.80.45.0/2575.80.45.1 to 75.80.45.12675.80.45.127126
9275.80.45.128/2575.80.45.129 to 75.80.45.25475.80.45.255126
9375.80.46.0/2575.80.46.1 to 75.80.46.12675.80.46.127126
9475.80.46.128/2575.80.46.129 to 75.80.46.25475.80.46.255126
9575.80.47.0/2575.80.47.1 to 75.80.47.12675.80.47.127126
9675.80.47.128/2575.80.47.129 to 75.80.47.25475.80.47.255126
9775.80.48.0/2575.80.48.1 to 75.80.48.12675.80.48.127126
9875.80.48.128/2575.80.48.129 to 75.80.48.25475.80.48.255126
9975.80.49.0/2575.80.49.1 to 75.80.49.12675.80.49.127126
10075.80.49.128/2575.80.49.129 to 75.80.49.25475.80.49.255126
10175.80.50.0/2575.80.50.1 to 75.80.50.12675.80.50.127126
10275.80.50.128/2575.80.50.129 to 75.80.50.25475.80.50.255126
10375.80.51.0/2575.80.51.1 to 75.80.51.12675.80.51.127126
10475.80.51.128/2575.80.51.129 to 75.80.51.25475.80.51.255126
10575.80.52.0/2575.80.52.1 to 75.80.52.12675.80.52.127126
10675.80.52.128/2575.80.52.129 to 75.80.52.25475.80.52.255126
10775.80.53.0/2575.80.53.1 to 75.80.53.12675.80.53.127126
10875.80.53.128/2575.80.53.129 to 75.80.53.25475.80.53.255126
10975.80.54.0/2575.80.54.1 to 75.80.54.12675.80.54.127126
11075.80.54.128/2575.80.54.129 to 75.80.54.25475.80.54.255126
11175.80.55.0/2575.80.55.1 to 75.80.55.12675.80.55.127126
11275.80.55.128/2575.80.55.129 to 75.80.55.25475.80.55.255126
11375.80.56.0/2575.80.56.1 to 75.80.56.12675.80.56.127126
11475.80.56.128/2575.80.56.129 to 75.80.56.25475.80.56.255126
11575.80.57.0/2575.80.57.1 to 75.80.57.12675.80.57.127126
11675.80.57.128/2575.80.57.129 to 75.80.57.25475.80.57.255126
11775.80.58.0/2575.80.58.1 to 75.80.58.12675.80.58.127126
11875.80.58.128/2575.80.58.129 to 75.80.58.25475.80.58.255126
11975.80.59.0/2575.80.59.1 to 75.80.59.12675.80.59.127126
12075.80.59.128/2575.80.59.129 to 75.80.59.25475.80.59.255126
12175.80.60.0/2575.80.60.1 to 75.80.60.12675.80.60.127126
12275.80.60.128/2575.80.60.129 to 75.80.60.25475.80.60.255126
12375.80.61.0/2575.80.61.1 to 75.80.61.12675.80.61.127126
12475.80.61.128/2575.80.61.129 to 75.80.61.25475.80.61.255126
12575.80.62.0/2575.80.62.1 to 75.80.62.12675.80.62.127126
12675.80.62.128/2575.80.62.129 to 75.80.62.25475.80.62.255126
12775.80.63.0/2575.80.63.1 to 75.80.63.12675.80.63.127126
12875.80.63.128/2575.80.63.129 to 75.80.63.25475.80.63.255126
12975.80.64.0/2575.80.64.1 to 75.80.64.12675.80.64.127126
13075.80.64.128/2575.80.64.129 to 75.80.64.25475.80.64.255126
13175.80.65.0/2575.80.65.1 to 75.80.65.12675.80.65.127126
13275.80.65.128/2575.80.65.129 to 75.80.65.25475.80.65.255126
13375.80.66.0/2575.80.66.1 to 75.80.66.12675.80.66.127126
13475.80.66.128/2575.80.66.129 to 75.80.66.25475.80.66.255126
13575.80.67.0/2575.80.67.1 to 75.80.67.12675.80.67.127126
13675.80.67.128/2575.80.67.129 to 75.80.67.25475.80.67.255126
13775.80.68.0/2575.80.68.1 to 75.80.68.12675.80.68.127126
13875.80.68.128/2575.80.68.129 to 75.80.68.25475.80.68.255126
13975.80.69.0/2575.80.69.1 to 75.80.69.12675.80.69.127126
14075.80.69.128/2575.80.69.129 to 75.80.69.25475.80.69.255126
14175.80.70.0/2575.80.70.1 to 75.80.70.12675.80.70.127126
14275.80.70.128/2575.80.70.129 to 75.80.70.25475.80.70.255126
14375.80.71.0/2575.80.71.1 to 75.80.71.12675.80.71.127126
14475.80.71.128/2575.80.71.129 to 75.80.71.25475.80.71.255126
14575.80.72.0/2575.80.72.1 to 75.80.72.12675.80.72.127126
14675.80.72.128/2575.80.72.129 to 75.80.72.25475.80.72.255126
14775.80.73.0/2575.80.73.1 to 75.80.73.12675.80.73.127126
14875.80.73.128/2575.80.73.129 to 75.80.73.25475.80.73.255126
14975.80.74.0/2575.80.74.1 to 75.80.74.12675.80.74.127126
15075.80.74.128/2575.80.74.129 to 75.80.74.25475.80.74.255126
15175.80.75.0/2575.80.75.1 to 75.80.75.12675.80.75.127126
15275.80.75.128/2575.80.75.129 to 75.80.75.25475.80.75.255126
15375.80.76.0/2575.80.76.1 to 75.80.76.12675.80.76.127126
15475.80.76.128/2575.80.76.129 to 75.80.76.25475.80.76.255126
15575.80.77.0/2575.80.77.1 to 75.80.77.12675.80.77.127126
15675.80.77.128/2575.80.77.129 to 75.80.77.25475.80.77.255126
15775.80.78.0/2575.80.78.1 to 75.80.78.12675.80.78.127126
15875.80.78.128/2575.80.78.129 to 75.80.78.25475.80.78.255126
15975.80.79.0/2575.80.79.1 to 75.80.79.12675.80.79.127126
16075.80.79.128/2575.80.79.129 to 75.80.79.25475.80.79.255126
16175.80.80.0/2575.80.80.1 to 75.80.80.12675.80.80.127126
16275.80.80.128/2575.80.80.129 to 75.80.80.25475.80.80.255126
16375.80.81.0/2575.80.81.1 to 75.80.81.12675.80.81.127126
16475.80.81.128/2575.80.81.129 to 75.80.81.25475.80.81.255126
16575.80.82.0/2575.80.82.1 to 75.80.82.12675.80.82.127126
16675.80.82.128/2575.80.82.129 to 75.80.82.25475.80.82.255126
16775.80.83.0/2575.80.83.1 to 75.80.83.12675.80.83.127126
16875.80.83.128/2575.80.83.129 to 75.80.83.25475.80.83.255126
16975.80.84.0/2575.80.84.1 to 75.80.84.12675.80.84.127126
17075.80.84.128/2575.80.84.129 to 75.80.84.25475.80.84.255126
17175.80.85.0/2575.80.85.1 to 75.80.85.12675.80.85.127126
17275.80.85.128/2575.80.85.129 to 75.80.85.25475.80.85.255126
17375.80.86.0/2575.80.86.1 to 75.80.86.12675.80.86.127126
17475.80.86.128/2575.80.86.129 to 75.80.86.25475.80.86.255126
17575.80.87.0/2575.80.87.1 to 75.80.87.12675.80.87.127126
17675.80.87.128/2575.80.87.129 to 75.80.87.25475.80.87.255126
17775.80.88.0/2575.80.88.1 to 75.80.88.12675.80.88.127126
17875.80.88.128/2575.80.88.129 to 75.80.88.25475.80.88.255126
17975.80.89.0/2575.80.89.1 to 75.80.89.12675.80.89.127126
18075.80.89.128/2575.80.89.129 to 75.80.89.25475.80.89.255126
18175.80.90.0/2575.80.90.1 to 75.80.90.12675.80.90.127126
18275.80.90.128/2575.80.90.129 to 75.80.90.25475.80.90.255126
18375.80.91.0/2575.80.91.1 to 75.80.91.12675.80.91.127126
18475.80.91.128/2575.80.91.129 to 75.80.91.25475.80.91.255126
18575.80.92.0/2575.80.92.1 to 75.80.92.12675.80.92.127126
18675.80.92.128/2575.80.92.129 to 75.80.92.25475.80.92.255126
18775.80.93.0/2575.80.93.1 to 75.80.93.12675.80.93.127126
18875.80.93.128/2575.80.93.129 to 75.80.93.25475.80.93.255126
18975.80.94.0/2575.80.94.1 to 75.80.94.12675.80.94.127126
19075.80.94.128/2575.80.94.129 to 75.80.94.25475.80.94.255126
19175.80.95.0/2575.80.95.1 to 75.80.95.12675.80.95.127126
19275.80.95.128/2575.80.95.129 to 75.80.95.25475.80.95.255126
19375.80.96.0/2575.80.96.1 to 75.80.96.12675.80.96.127126
19475.80.96.128/2575.80.96.129 to 75.80.96.25475.80.96.255126
19575.80.97.0/2575.80.97.1 to 75.80.97.12675.80.97.127126
19675.80.97.128/2575.80.97.129 to 75.80.97.25475.80.97.255126
19775.80.98.0/2575.80.98.1 to 75.80.98.12675.80.98.127126
19875.80.98.128/2575.80.98.129 to 75.80.98.25475.80.98.255126
19975.80.99.0/2575.80.99.1 to 75.80.99.12675.80.99.127126
20075.80.99.128/2575.80.99.129 to 75.80.99.25475.80.99.255126
20175.80.100.0/2575.80.100.1 to 75.80.100.12675.80.100.127126
20275.80.100.128/2575.80.100.129 to 75.80.100.25475.80.100.255126
20375.80.101.0/2575.80.101.1 to 75.80.101.12675.80.101.127126
20475.80.101.128/2575.80.101.129 to 75.80.101.25475.80.101.255126
20575.80.102.0/2575.80.102.1 to 75.80.102.12675.80.102.127126
20675.80.102.128/2575.80.102.129 to 75.80.102.25475.80.102.255126
20775.80.103.0/2575.80.103.1 to 75.80.103.12675.80.103.127126
20875.80.103.128/2575.80.103.129 to 75.80.103.25475.80.103.255126
20975.80.104.0/2575.80.104.1 to 75.80.104.12675.80.104.127126
21075.80.104.128/2575.80.104.129 to 75.80.104.25475.80.104.255126
21175.80.105.0/2575.80.105.1 to 75.80.105.12675.80.105.127126
21275.80.105.128/2575.80.105.129 to 75.80.105.25475.80.105.255126
21375.80.106.0/2575.80.106.1 to 75.80.106.12675.80.106.127126
21475.80.106.128/2575.80.106.129 to 75.80.106.25475.80.106.255126
21575.80.107.0/2575.80.107.1 to 75.80.107.12675.80.107.127126
21675.80.107.128/2575.80.107.129 to 75.80.107.25475.80.107.255126
21775.80.108.0/2575.80.108.1 to 75.80.108.12675.80.108.127126
21875.80.108.128/2575.80.108.129 to 75.80.108.25475.80.108.255126
21975.80.109.0/2575.80.109.1 to 75.80.109.12675.80.109.127126
22075.80.109.128/2575.80.109.129 to 75.80.109.25475.80.109.255126
22175.80.110.0/2575.80.110.1 to 75.80.110.12675.80.110.127126
22275.80.110.128/2575.80.110.129 to 75.80.110.25475.80.110.255126
22375.80.111.0/2575.80.111.1 to 75.80.111.12675.80.111.127126
22475.80.111.128/2575.80.111.129 to 75.80.111.25475.80.111.255126
22575.80.112.0/2575.80.112.1 to 75.80.112.12675.80.112.127126
22675.80.112.128/2575.80.112.129 to 75.80.112.25475.80.112.255126
22775.80.113.0/2575.80.113.1 to 75.80.113.12675.80.113.127126
22875.80.113.128/2575.80.113.129 to 75.80.113.25475.80.113.255126
22975.80.114.0/2575.80.114.1 to 75.80.114.12675.80.114.127126
23075.80.114.128/2575.80.114.129 to 75.80.114.25475.80.114.255126
23175.80.115.0/2575.80.115.1 to 75.80.115.12675.80.115.127126
23275.80.115.128/2575.80.115.129 to 75.80.115.25475.80.115.255126
23375.80.116.0/2575.80.116.1 to 75.80.116.12675.80.116.127126
23475.80.116.128/2575.80.116.129 to 75.80.116.25475.80.116.255126
23575.80.117.0/2575.80.117.1 to 75.80.117.12675.80.117.127126
23675.80.117.128/2575.80.117.129 to 75.80.117.25475.80.117.255126
23775.80.118.0/2575.80.118.1 to 75.80.118.12675.80.118.127126
23875.80.118.128/2575.80.118.129 to 75.80.118.25475.80.118.255126
23975.80.119.0/2575.80.119.1 to 75.80.119.12675.80.119.127126
24075.80.119.128/2575.80.119.129 to 75.80.119.25475.80.119.255126
24175.80.120.0/2575.80.120.1 to 75.80.120.12675.80.120.127126
24275.80.120.128/2575.80.120.129 to 75.80.120.25475.80.120.255126
24375.80.121.0/2575.80.121.1 to 75.80.121.12675.80.121.127126
24475.80.121.128/2575.80.121.129 to 75.80.121.25475.80.121.255126
24575.80.122.0/2575.80.122.1 to 75.80.122.12675.80.122.127126
24675.80.122.128/2575.80.122.129 to 75.80.122.25475.80.122.255126
24775.80.123.0/2575.80.123.1 to 75.80.123.12675.80.123.127126
24875.80.123.128/2575.80.123.129 to 75.80.123.25475.80.123.255126
24975.80.124.0/2575.80.124.1 to 75.80.124.12675.80.124.127126
25075.80.124.128/2575.80.124.129 to 75.80.124.25475.80.124.255126
25175.80.125.0/2575.80.125.1 to 75.80.125.12675.80.125.127126
25275.80.125.128/2575.80.125.129 to 75.80.125.25475.80.125.255126
25375.80.126.0/2575.80.126.1 to 75.80.126.12675.80.126.127126
25475.80.126.128/2575.80.126.129 to 75.80.126.25475.80.126.255126
25575.80.127.0/2575.80.127.1 to 75.80.127.12675.80.127.127126
25675.80.127.128/2575.80.127.129 to 75.80.127.25475.80.127.255126

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.