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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.

Network28.64.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
28.64.0.0
Broadcast address
28.67.255.255
First usable
28.64.0.1
Last usable
28.67.255.254
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 1C400000 · Integer 473956352 to 474218495
Reverse DNS zones
64.28.in-addr.arpa
65.28.in-addr.arpa
66.28.in-addr.arpa
67.28.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
Address00011100.01000000.00000000.0000000028.64.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00011100.01000000.00000000.0000000028.64.0.0
Broadcast00011100.01000011.11111111.1111111128.67.255.255
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)

28.64.0.0/14 makes 2,048 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
128.64.0.0/2528.64.0.1 to 28.64.0.12628.64.0.127126
228.64.0.128/2528.64.0.129 to 28.64.0.25428.64.0.255126
328.64.1.0/2528.64.1.1 to 28.64.1.12628.64.1.127126
428.64.1.128/2528.64.1.129 to 28.64.1.25428.64.1.255126
528.64.2.0/2528.64.2.1 to 28.64.2.12628.64.2.127126
628.64.2.128/2528.64.2.129 to 28.64.2.25428.64.2.255126
728.64.3.0/2528.64.3.1 to 28.64.3.12628.64.3.127126
828.64.3.128/2528.64.3.129 to 28.64.3.25428.64.3.255126
928.64.4.0/2528.64.4.1 to 28.64.4.12628.64.4.127126
1028.64.4.128/2528.64.4.129 to 28.64.4.25428.64.4.255126
1128.64.5.0/2528.64.5.1 to 28.64.5.12628.64.5.127126
1228.64.5.128/2528.64.5.129 to 28.64.5.25428.64.5.255126
1328.64.6.0/2528.64.6.1 to 28.64.6.12628.64.6.127126
1428.64.6.128/2528.64.6.129 to 28.64.6.25428.64.6.255126
1528.64.7.0/2528.64.7.1 to 28.64.7.12628.64.7.127126
1628.64.7.128/2528.64.7.129 to 28.64.7.25428.64.7.255126
1728.64.8.0/2528.64.8.1 to 28.64.8.12628.64.8.127126
1828.64.8.128/2528.64.8.129 to 28.64.8.25428.64.8.255126
1928.64.9.0/2528.64.9.1 to 28.64.9.12628.64.9.127126
2028.64.9.128/2528.64.9.129 to 28.64.9.25428.64.9.255126
2128.64.10.0/2528.64.10.1 to 28.64.10.12628.64.10.127126
2228.64.10.128/2528.64.10.129 to 28.64.10.25428.64.10.255126
2328.64.11.0/2528.64.11.1 to 28.64.11.12628.64.11.127126
2428.64.11.128/2528.64.11.129 to 28.64.11.25428.64.11.255126
2528.64.12.0/2528.64.12.1 to 28.64.12.12628.64.12.127126
2628.64.12.128/2528.64.12.129 to 28.64.12.25428.64.12.255126
2728.64.13.0/2528.64.13.1 to 28.64.13.12628.64.13.127126
2828.64.13.128/2528.64.13.129 to 28.64.13.25428.64.13.255126
2928.64.14.0/2528.64.14.1 to 28.64.14.12628.64.14.127126
3028.64.14.128/2528.64.14.129 to 28.64.14.25428.64.14.255126
3128.64.15.0/2528.64.15.1 to 28.64.15.12628.64.15.127126
3228.64.15.128/2528.64.15.129 to 28.64.15.25428.64.15.255126
3328.64.16.0/2528.64.16.1 to 28.64.16.12628.64.16.127126
3428.64.16.128/2528.64.16.129 to 28.64.16.25428.64.16.255126
3528.64.17.0/2528.64.17.1 to 28.64.17.12628.64.17.127126
3628.64.17.128/2528.64.17.129 to 28.64.17.25428.64.17.255126
3728.64.18.0/2528.64.18.1 to 28.64.18.12628.64.18.127126
3828.64.18.128/2528.64.18.129 to 28.64.18.25428.64.18.255126
3928.64.19.0/2528.64.19.1 to 28.64.19.12628.64.19.127126
4028.64.19.128/2528.64.19.129 to 28.64.19.25428.64.19.255126
4128.64.20.0/2528.64.20.1 to 28.64.20.12628.64.20.127126
4228.64.20.128/2528.64.20.129 to 28.64.20.25428.64.20.255126
4328.64.21.0/2528.64.21.1 to 28.64.21.12628.64.21.127126
4428.64.21.128/2528.64.21.129 to 28.64.21.25428.64.21.255126
4528.64.22.0/2528.64.22.1 to 28.64.22.12628.64.22.127126
4628.64.22.128/2528.64.22.129 to 28.64.22.25428.64.22.255126
4728.64.23.0/2528.64.23.1 to 28.64.23.12628.64.23.127126
4828.64.23.128/2528.64.23.129 to 28.64.23.25428.64.23.255126
4928.64.24.0/2528.64.24.1 to 28.64.24.12628.64.24.127126
5028.64.24.128/2528.64.24.129 to 28.64.24.25428.64.24.255126
5128.64.25.0/2528.64.25.1 to 28.64.25.12628.64.25.127126
5228.64.25.128/2528.64.25.129 to 28.64.25.25428.64.25.255126
5328.64.26.0/2528.64.26.1 to 28.64.26.12628.64.26.127126
5428.64.26.128/2528.64.26.129 to 28.64.26.25428.64.26.255126
5528.64.27.0/2528.64.27.1 to 28.64.27.12628.64.27.127126
5628.64.27.128/2528.64.27.129 to 28.64.27.25428.64.27.255126
5728.64.28.0/2528.64.28.1 to 28.64.28.12628.64.28.127126
5828.64.28.128/2528.64.28.129 to 28.64.28.25428.64.28.255126
5928.64.29.0/2528.64.29.1 to 28.64.29.12628.64.29.127126
6028.64.29.128/2528.64.29.129 to 28.64.29.25428.64.29.255126
6128.64.30.0/2528.64.30.1 to 28.64.30.12628.64.30.127126
6228.64.30.128/2528.64.30.129 to 28.64.30.25428.64.30.255126
6328.64.31.0/2528.64.31.1 to 28.64.31.12628.64.31.127126
6428.64.31.128/2528.64.31.129 to 28.64.31.25428.64.31.255126
6528.64.32.0/2528.64.32.1 to 28.64.32.12628.64.32.127126
6628.64.32.128/2528.64.32.129 to 28.64.32.25428.64.32.255126
6728.64.33.0/2528.64.33.1 to 28.64.33.12628.64.33.127126
6828.64.33.128/2528.64.33.129 to 28.64.33.25428.64.33.255126
6928.64.34.0/2528.64.34.1 to 28.64.34.12628.64.34.127126
7028.64.34.128/2528.64.34.129 to 28.64.34.25428.64.34.255126
7128.64.35.0/2528.64.35.1 to 28.64.35.12628.64.35.127126
7228.64.35.128/2528.64.35.129 to 28.64.35.25428.64.35.255126
7328.64.36.0/2528.64.36.1 to 28.64.36.12628.64.36.127126
7428.64.36.128/2528.64.36.129 to 28.64.36.25428.64.36.255126
7528.64.37.0/2528.64.37.1 to 28.64.37.12628.64.37.127126
7628.64.37.128/2528.64.37.129 to 28.64.37.25428.64.37.255126
7728.64.38.0/2528.64.38.1 to 28.64.38.12628.64.38.127126
7828.64.38.128/2528.64.38.129 to 28.64.38.25428.64.38.255126
7928.64.39.0/2528.64.39.1 to 28.64.39.12628.64.39.127126
8028.64.39.128/2528.64.39.129 to 28.64.39.25428.64.39.255126
8128.64.40.0/2528.64.40.1 to 28.64.40.12628.64.40.127126
8228.64.40.128/2528.64.40.129 to 28.64.40.25428.64.40.255126
8328.64.41.0/2528.64.41.1 to 28.64.41.12628.64.41.127126
8428.64.41.128/2528.64.41.129 to 28.64.41.25428.64.41.255126
8528.64.42.0/2528.64.42.1 to 28.64.42.12628.64.42.127126
8628.64.42.128/2528.64.42.129 to 28.64.42.25428.64.42.255126
8728.64.43.0/2528.64.43.1 to 28.64.43.12628.64.43.127126
8828.64.43.128/2528.64.43.129 to 28.64.43.25428.64.43.255126
8928.64.44.0/2528.64.44.1 to 28.64.44.12628.64.44.127126
9028.64.44.128/2528.64.44.129 to 28.64.44.25428.64.44.255126
9128.64.45.0/2528.64.45.1 to 28.64.45.12628.64.45.127126
9228.64.45.128/2528.64.45.129 to 28.64.45.25428.64.45.255126
9328.64.46.0/2528.64.46.1 to 28.64.46.12628.64.46.127126
9428.64.46.128/2528.64.46.129 to 28.64.46.25428.64.46.255126
9528.64.47.0/2528.64.47.1 to 28.64.47.12628.64.47.127126
9628.64.47.128/2528.64.47.129 to 28.64.47.25428.64.47.255126
9728.64.48.0/2528.64.48.1 to 28.64.48.12628.64.48.127126
9828.64.48.128/2528.64.48.129 to 28.64.48.25428.64.48.255126
9928.64.49.0/2528.64.49.1 to 28.64.49.12628.64.49.127126
10028.64.49.128/2528.64.49.129 to 28.64.49.25428.64.49.255126
10128.64.50.0/2528.64.50.1 to 28.64.50.12628.64.50.127126
10228.64.50.128/2528.64.50.129 to 28.64.50.25428.64.50.255126
10328.64.51.0/2528.64.51.1 to 28.64.51.12628.64.51.127126
10428.64.51.128/2528.64.51.129 to 28.64.51.25428.64.51.255126
10528.64.52.0/2528.64.52.1 to 28.64.52.12628.64.52.127126
10628.64.52.128/2528.64.52.129 to 28.64.52.25428.64.52.255126
10728.64.53.0/2528.64.53.1 to 28.64.53.12628.64.53.127126
10828.64.53.128/2528.64.53.129 to 28.64.53.25428.64.53.255126
10928.64.54.0/2528.64.54.1 to 28.64.54.12628.64.54.127126
11028.64.54.128/2528.64.54.129 to 28.64.54.25428.64.54.255126
11128.64.55.0/2528.64.55.1 to 28.64.55.12628.64.55.127126
11228.64.55.128/2528.64.55.129 to 28.64.55.25428.64.55.255126
11328.64.56.0/2528.64.56.1 to 28.64.56.12628.64.56.127126
11428.64.56.128/2528.64.56.129 to 28.64.56.25428.64.56.255126
11528.64.57.0/2528.64.57.1 to 28.64.57.12628.64.57.127126
11628.64.57.128/2528.64.57.129 to 28.64.57.25428.64.57.255126
11728.64.58.0/2528.64.58.1 to 28.64.58.12628.64.58.127126
11828.64.58.128/2528.64.58.129 to 28.64.58.25428.64.58.255126
11928.64.59.0/2528.64.59.1 to 28.64.59.12628.64.59.127126
12028.64.59.128/2528.64.59.129 to 28.64.59.25428.64.59.255126
12128.64.60.0/2528.64.60.1 to 28.64.60.12628.64.60.127126
12228.64.60.128/2528.64.60.129 to 28.64.60.25428.64.60.255126
12328.64.61.0/2528.64.61.1 to 28.64.61.12628.64.61.127126
12428.64.61.128/2528.64.61.129 to 28.64.61.25428.64.61.255126
12528.64.62.0/2528.64.62.1 to 28.64.62.12628.64.62.127126
12628.64.62.128/2528.64.62.129 to 28.64.62.25428.64.62.255126
12728.64.63.0/2528.64.63.1 to 28.64.63.12628.64.63.127126
12828.64.63.128/2528.64.63.129 to 28.64.63.25428.64.63.255126
12928.64.64.0/2528.64.64.1 to 28.64.64.12628.64.64.127126
13028.64.64.128/2528.64.64.129 to 28.64.64.25428.64.64.255126
13128.64.65.0/2528.64.65.1 to 28.64.65.12628.64.65.127126
13228.64.65.128/2528.64.65.129 to 28.64.65.25428.64.65.255126
13328.64.66.0/2528.64.66.1 to 28.64.66.12628.64.66.127126
13428.64.66.128/2528.64.66.129 to 28.64.66.25428.64.66.255126
13528.64.67.0/2528.64.67.1 to 28.64.67.12628.64.67.127126
13628.64.67.128/2528.64.67.129 to 28.64.67.25428.64.67.255126
13728.64.68.0/2528.64.68.1 to 28.64.68.12628.64.68.127126
13828.64.68.128/2528.64.68.129 to 28.64.68.25428.64.68.255126
13928.64.69.0/2528.64.69.1 to 28.64.69.12628.64.69.127126
14028.64.69.128/2528.64.69.129 to 28.64.69.25428.64.69.255126
14128.64.70.0/2528.64.70.1 to 28.64.70.12628.64.70.127126
14228.64.70.128/2528.64.70.129 to 28.64.70.25428.64.70.255126
14328.64.71.0/2528.64.71.1 to 28.64.71.12628.64.71.127126
14428.64.71.128/2528.64.71.129 to 28.64.71.25428.64.71.255126
14528.64.72.0/2528.64.72.1 to 28.64.72.12628.64.72.127126
14628.64.72.128/2528.64.72.129 to 28.64.72.25428.64.72.255126
14728.64.73.0/2528.64.73.1 to 28.64.73.12628.64.73.127126
14828.64.73.128/2528.64.73.129 to 28.64.73.25428.64.73.255126
14928.64.74.0/2528.64.74.1 to 28.64.74.12628.64.74.127126
15028.64.74.128/2528.64.74.129 to 28.64.74.25428.64.74.255126
15128.64.75.0/2528.64.75.1 to 28.64.75.12628.64.75.127126
15228.64.75.128/2528.64.75.129 to 28.64.75.25428.64.75.255126
15328.64.76.0/2528.64.76.1 to 28.64.76.12628.64.76.127126
15428.64.76.128/2528.64.76.129 to 28.64.76.25428.64.76.255126
15528.64.77.0/2528.64.77.1 to 28.64.77.12628.64.77.127126
15628.64.77.128/2528.64.77.129 to 28.64.77.25428.64.77.255126
15728.64.78.0/2528.64.78.1 to 28.64.78.12628.64.78.127126
15828.64.78.128/2528.64.78.129 to 28.64.78.25428.64.78.255126
15928.64.79.0/2528.64.79.1 to 28.64.79.12628.64.79.127126
16028.64.79.128/2528.64.79.129 to 28.64.79.25428.64.79.255126
16128.64.80.0/2528.64.80.1 to 28.64.80.12628.64.80.127126
16228.64.80.128/2528.64.80.129 to 28.64.80.25428.64.80.255126
16328.64.81.0/2528.64.81.1 to 28.64.81.12628.64.81.127126
16428.64.81.128/2528.64.81.129 to 28.64.81.25428.64.81.255126
16528.64.82.0/2528.64.82.1 to 28.64.82.12628.64.82.127126
16628.64.82.128/2528.64.82.129 to 28.64.82.25428.64.82.255126
16728.64.83.0/2528.64.83.1 to 28.64.83.12628.64.83.127126
16828.64.83.128/2528.64.83.129 to 28.64.83.25428.64.83.255126
16928.64.84.0/2528.64.84.1 to 28.64.84.12628.64.84.127126
17028.64.84.128/2528.64.84.129 to 28.64.84.25428.64.84.255126
17128.64.85.0/2528.64.85.1 to 28.64.85.12628.64.85.127126
17228.64.85.128/2528.64.85.129 to 28.64.85.25428.64.85.255126
17328.64.86.0/2528.64.86.1 to 28.64.86.12628.64.86.127126
17428.64.86.128/2528.64.86.129 to 28.64.86.25428.64.86.255126
17528.64.87.0/2528.64.87.1 to 28.64.87.12628.64.87.127126
17628.64.87.128/2528.64.87.129 to 28.64.87.25428.64.87.255126
17728.64.88.0/2528.64.88.1 to 28.64.88.12628.64.88.127126
17828.64.88.128/2528.64.88.129 to 28.64.88.25428.64.88.255126
17928.64.89.0/2528.64.89.1 to 28.64.89.12628.64.89.127126
18028.64.89.128/2528.64.89.129 to 28.64.89.25428.64.89.255126
18128.64.90.0/2528.64.90.1 to 28.64.90.12628.64.90.127126
18228.64.90.128/2528.64.90.129 to 28.64.90.25428.64.90.255126
18328.64.91.0/2528.64.91.1 to 28.64.91.12628.64.91.127126
18428.64.91.128/2528.64.91.129 to 28.64.91.25428.64.91.255126
18528.64.92.0/2528.64.92.1 to 28.64.92.12628.64.92.127126
18628.64.92.128/2528.64.92.129 to 28.64.92.25428.64.92.255126
18728.64.93.0/2528.64.93.1 to 28.64.93.12628.64.93.127126
18828.64.93.128/2528.64.93.129 to 28.64.93.25428.64.93.255126
18928.64.94.0/2528.64.94.1 to 28.64.94.12628.64.94.127126
19028.64.94.128/2528.64.94.129 to 28.64.94.25428.64.94.255126
19128.64.95.0/2528.64.95.1 to 28.64.95.12628.64.95.127126
19228.64.95.128/2528.64.95.129 to 28.64.95.25428.64.95.255126
19328.64.96.0/2528.64.96.1 to 28.64.96.12628.64.96.127126
19428.64.96.128/2528.64.96.129 to 28.64.96.25428.64.96.255126
19528.64.97.0/2528.64.97.1 to 28.64.97.12628.64.97.127126
19628.64.97.128/2528.64.97.129 to 28.64.97.25428.64.97.255126
19728.64.98.0/2528.64.98.1 to 28.64.98.12628.64.98.127126
19828.64.98.128/2528.64.98.129 to 28.64.98.25428.64.98.255126
19928.64.99.0/2528.64.99.1 to 28.64.99.12628.64.99.127126
20028.64.99.128/2528.64.99.129 to 28.64.99.25428.64.99.255126
20128.64.100.0/2528.64.100.1 to 28.64.100.12628.64.100.127126
20228.64.100.128/2528.64.100.129 to 28.64.100.25428.64.100.255126
20328.64.101.0/2528.64.101.1 to 28.64.101.12628.64.101.127126
20428.64.101.128/2528.64.101.129 to 28.64.101.25428.64.101.255126
20528.64.102.0/2528.64.102.1 to 28.64.102.12628.64.102.127126
20628.64.102.128/2528.64.102.129 to 28.64.102.25428.64.102.255126
20728.64.103.0/2528.64.103.1 to 28.64.103.12628.64.103.127126
20828.64.103.128/2528.64.103.129 to 28.64.103.25428.64.103.255126
20928.64.104.0/2528.64.104.1 to 28.64.104.12628.64.104.127126
21028.64.104.128/2528.64.104.129 to 28.64.104.25428.64.104.255126
21128.64.105.0/2528.64.105.1 to 28.64.105.12628.64.105.127126
21228.64.105.128/2528.64.105.129 to 28.64.105.25428.64.105.255126
21328.64.106.0/2528.64.106.1 to 28.64.106.12628.64.106.127126
21428.64.106.128/2528.64.106.129 to 28.64.106.25428.64.106.255126
21528.64.107.0/2528.64.107.1 to 28.64.107.12628.64.107.127126
21628.64.107.128/2528.64.107.129 to 28.64.107.25428.64.107.255126
21728.64.108.0/2528.64.108.1 to 28.64.108.12628.64.108.127126
21828.64.108.128/2528.64.108.129 to 28.64.108.25428.64.108.255126
21928.64.109.0/2528.64.109.1 to 28.64.109.12628.64.109.127126
22028.64.109.128/2528.64.109.129 to 28.64.109.25428.64.109.255126
22128.64.110.0/2528.64.110.1 to 28.64.110.12628.64.110.127126
22228.64.110.128/2528.64.110.129 to 28.64.110.25428.64.110.255126
22328.64.111.0/2528.64.111.1 to 28.64.111.12628.64.111.127126
22428.64.111.128/2528.64.111.129 to 28.64.111.25428.64.111.255126
22528.64.112.0/2528.64.112.1 to 28.64.112.12628.64.112.127126
22628.64.112.128/2528.64.112.129 to 28.64.112.25428.64.112.255126
22728.64.113.0/2528.64.113.1 to 28.64.113.12628.64.113.127126
22828.64.113.128/2528.64.113.129 to 28.64.113.25428.64.113.255126
22928.64.114.0/2528.64.114.1 to 28.64.114.12628.64.114.127126
23028.64.114.128/2528.64.114.129 to 28.64.114.25428.64.114.255126
23128.64.115.0/2528.64.115.1 to 28.64.115.12628.64.115.127126
23228.64.115.128/2528.64.115.129 to 28.64.115.25428.64.115.255126
23328.64.116.0/2528.64.116.1 to 28.64.116.12628.64.116.127126
23428.64.116.128/2528.64.116.129 to 28.64.116.25428.64.116.255126
23528.64.117.0/2528.64.117.1 to 28.64.117.12628.64.117.127126
23628.64.117.128/2528.64.117.129 to 28.64.117.25428.64.117.255126
23728.64.118.0/2528.64.118.1 to 28.64.118.12628.64.118.127126
23828.64.118.128/2528.64.118.129 to 28.64.118.25428.64.118.255126
23928.64.119.0/2528.64.119.1 to 28.64.119.12628.64.119.127126
24028.64.119.128/2528.64.119.129 to 28.64.119.25428.64.119.255126
24128.64.120.0/2528.64.120.1 to 28.64.120.12628.64.120.127126
24228.64.120.128/2528.64.120.129 to 28.64.120.25428.64.120.255126
24328.64.121.0/2528.64.121.1 to 28.64.121.12628.64.121.127126
24428.64.121.128/2528.64.121.129 to 28.64.121.25428.64.121.255126
24528.64.122.0/2528.64.122.1 to 28.64.122.12628.64.122.127126
24628.64.122.128/2528.64.122.129 to 28.64.122.25428.64.122.255126
24728.64.123.0/2528.64.123.1 to 28.64.123.12628.64.123.127126
24828.64.123.128/2528.64.123.129 to 28.64.123.25428.64.123.255126
24928.64.124.0/2528.64.124.1 to 28.64.124.12628.64.124.127126
25028.64.124.128/2528.64.124.129 to 28.64.124.25428.64.124.255126
25128.64.125.0/2528.64.125.1 to 28.64.125.12628.64.125.127126
25228.64.125.128/2528.64.125.129 to 28.64.125.25428.64.125.255126
25328.64.126.0/2528.64.126.1 to 28.64.126.12628.64.126.127126
25428.64.126.128/2528.64.126.129 to 28.64.126.25428.64.126.255126
25528.64.127.0/2528.64.127.1 to 28.64.127.12628.64.127.127126
25628.64.127.128/2528.64.127.129 to 28.64.127.25428.64.127.255126

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.