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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.

Network38.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
38.76.0.0
Broadcast address
38.79.255.255
First usable
38.76.0.1
Last usable
38.79.255.254
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 264C0000 · Integer 642514944 to 642777087
Reverse DNS zones
76.38.in-addr.arpa
77.38.in-addr.arpa
78.38.in-addr.arpa
79.38.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
Address00100110.01001100.00000000.0000000038.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00100110.01001100.00000000.0000000038.76.0.0
Broadcast00100110.01001111.11111111.1111111138.79.255.255
Split into smaller subnets/25

38.76.0.0/14 makes 2,048 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
138.76.0.0/2538.76.0.1 to 38.76.0.12638.76.0.127126
238.76.0.128/2538.76.0.129 to 38.76.0.25438.76.0.255126
338.76.1.0/2538.76.1.1 to 38.76.1.12638.76.1.127126
438.76.1.128/2538.76.1.129 to 38.76.1.25438.76.1.255126
538.76.2.0/2538.76.2.1 to 38.76.2.12638.76.2.127126
638.76.2.128/2538.76.2.129 to 38.76.2.25438.76.2.255126
738.76.3.0/2538.76.3.1 to 38.76.3.12638.76.3.127126
838.76.3.128/2538.76.3.129 to 38.76.3.25438.76.3.255126
938.76.4.0/2538.76.4.1 to 38.76.4.12638.76.4.127126
1038.76.4.128/2538.76.4.129 to 38.76.4.25438.76.4.255126
1138.76.5.0/2538.76.5.1 to 38.76.5.12638.76.5.127126
1238.76.5.128/2538.76.5.129 to 38.76.5.25438.76.5.255126
1338.76.6.0/2538.76.6.1 to 38.76.6.12638.76.6.127126
1438.76.6.128/2538.76.6.129 to 38.76.6.25438.76.6.255126
1538.76.7.0/2538.76.7.1 to 38.76.7.12638.76.7.127126
1638.76.7.128/2538.76.7.129 to 38.76.7.25438.76.7.255126
1738.76.8.0/2538.76.8.1 to 38.76.8.12638.76.8.127126
1838.76.8.128/2538.76.8.129 to 38.76.8.25438.76.8.255126
1938.76.9.0/2538.76.9.1 to 38.76.9.12638.76.9.127126
2038.76.9.128/2538.76.9.129 to 38.76.9.25438.76.9.255126
2138.76.10.0/2538.76.10.1 to 38.76.10.12638.76.10.127126
2238.76.10.128/2538.76.10.129 to 38.76.10.25438.76.10.255126
2338.76.11.0/2538.76.11.1 to 38.76.11.12638.76.11.127126
2438.76.11.128/2538.76.11.129 to 38.76.11.25438.76.11.255126
2538.76.12.0/2538.76.12.1 to 38.76.12.12638.76.12.127126
2638.76.12.128/2538.76.12.129 to 38.76.12.25438.76.12.255126
2738.76.13.0/2538.76.13.1 to 38.76.13.12638.76.13.127126
2838.76.13.128/2538.76.13.129 to 38.76.13.25438.76.13.255126
2938.76.14.0/2538.76.14.1 to 38.76.14.12638.76.14.127126
3038.76.14.128/2538.76.14.129 to 38.76.14.25438.76.14.255126
3138.76.15.0/2538.76.15.1 to 38.76.15.12638.76.15.127126
3238.76.15.128/2538.76.15.129 to 38.76.15.25438.76.15.255126
3338.76.16.0/2538.76.16.1 to 38.76.16.12638.76.16.127126
3438.76.16.128/2538.76.16.129 to 38.76.16.25438.76.16.255126
3538.76.17.0/2538.76.17.1 to 38.76.17.12638.76.17.127126
3638.76.17.128/2538.76.17.129 to 38.76.17.25438.76.17.255126
3738.76.18.0/2538.76.18.1 to 38.76.18.12638.76.18.127126
3838.76.18.128/2538.76.18.129 to 38.76.18.25438.76.18.255126
3938.76.19.0/2538.76.19.1 to 38.76.19.12638.76.19.127126
4038.76.19.128/2538.76.19.129 to 38.76.19.25438.76.19.255126
4138.76.20.0/2538.76.20.1 to 38.76.20.12638.76.20.127126
4238.76.20.128/2538.76.20.129 to 38.76.20.25438.76.20.255126
4338.76.21.0/2538.76.21.1 to 38.76.21.12638.76.21.127126
4438.76.21.128/2538.76.21.129 to 38.76.21.25438.76.21.255126
4538.76.22.0/2538.76.22.1 to 38.76.22.12638.76.22.127126
4638.76.22.128/2538.76.22.129 to 38.76.22.25438.76.22.255126
4738.76.23.0/2538.76.23.1 to 38.76.23.12638.76.23.127126
4838.76.23.128/2538.76.23.129 to 38.76.23.25438.76.23.255126
4938.76.24.0/2538.76.24.1 to 38.76.24.12638.76.24.127126
5038.76.24.128/2538.76.24.129 to 38.76.24.25438.76.24.255126
5138.76.25.0/2538.76.25.1 to 38.76.25.12638.76.25.127126
5238.76.25.128/2538.76.25.129 to 38.76.25.25438.76.25.255126
5338.76.26.0/2538.76.26.1 to 38.76.26.12638.76.26.127126
5438.76.26.128/2538.76.26.129 to 38.76.26.25438.76.26.255126
5538.76.27.0/2538.76.27.1 to 38.76.27.12638.76.27.127126
5638.76.27.128/2538.76.27.129 to 38.76.27.25438.76.27.255126
5738.76.28.0/2538.76.28.1 to 38.76.28.12638.76.28.127126
5838.76.28.128/2538.76.28.129 to 38.76.28.25438.76.28.255126
5938.76.29.0/2538.76.29.1 to 38.76.29.12638.76.29.127126
6038.76.29.128/2538.76.29.129 to 38.76.29.25438.76.29.255126
6138.76.30.0/2538.76.30.1 to 38.76.30.12638.76.30.127126
6238.76.30.128/2538.76.30.129 to 38.76.30.25438.76.30.255126
6338.76.31.0/2538.76.31.1 to 38.76.31.12638.76.31.127126
6438.76.31.128/2538.76.31.129 to 38.76.31.25438.76.31.255126
6538.76.32.0/2538.76.32.1 to 38.76.32.12638.76.32.127126
6638.76.32.128/2538.76.32.129 to 38.76.32.25438.76.32.255126
6738.76.33.0/2538.76.33.1 to 38.76.33.12638.76.33.127126
6838.76.33.128/2538.76.33.129 to 38.76.33.25438.76.33.255126
6938.76.34.0/2538.76.34.1 to 38.76.34.12638.76.34.127126
7038.76.34.128/2538.76.34.129 to 38.76.34.25438.76.34.255126
7138.76.35.0/2538.76.35.1 to 38.76.35.12638.76.35.127126
7238.76.35.128/2538.76.35.129 to 38.76.35.25438.76.35.255126
7338.76.36.0/2538.76.36.1 to 38.76.36.12638.76.36.127126
7438.76.36.128/2538.76.36.129 to 38.76.36.25438.76.36.255126
7538.76.37.0/2538.76.37.1 to 38.76.37.12638.76.37.127126
7638.76.37.128/2538.76.37.129 to 38.76.37.25438.76.37.255126
7738.76.38.0/2538.76.38.1 to 38.76.38.12638.76.38.127126
7838.76.38.128/2538.76.38.129 to 38.76.38.25438.76.38.255126
7938.76.39.0/2538.76.39.1 to 38.76.39.12638.76.39.127126
8038.76.39.128/2538.76.39.129 to 38.76.39.25438.76.39.255126
8138.76.40.0/2538.76.40.1 to 38.76.40.12638.76.40.127126
8238.76.40.128/2538.76.40.129 to 38.76.40.25438.76.40.255126
8338.76.41.0/2538.76.41.1 to 38.76.41.12638.76.41.127126
8438.76.41.128/2538.76.41.129 to 38.76.41.25438.76.41.255126
8538.76.42.0/2538.76.42.1 to 38.76.42.12638.76.42.127126
8638.76.42.128/2538.76.42.129 to 38.76.42.25438.76.42.255126
8738.76.43.0/2538.76.43.1 to 38.76.43.12638.76.43.127126
8838.76.43.128/2538.76.43.129 to 38.76.43.25438.76.43.255126
8938.76.44.0/2538.76.44.1 to 38.76.44.12638.76.44.127126
9038.76.44.128/2538.76.44.129 to 38.76.44.25438.76.44.255126
9138.76.45.0/2538.76.45.1 to 38.76.45.12638.76.45.127126
9238.76.45.128/2538.76.45.129 to 38.76.45.25438.76.45.255126
9338.76.46.0/2538.76.46.1 to 38.76.46.12638.76.46.127126
9438.76.46.128/2538.76.46.129 to 38.76.46.25438.76.46.255126
9538.76.47.0/2538.76.47.1 to 38.76.47.12638.76.47.127126
9638.76.47.128/2538.76.47.129 to 38.76.47.25438.76.47.255126
9738.76.48.0/2538.76.48.1 to 38.76.48.12638.76.48.127126
9838.76.48.128/2538.76.48.129 to 38.76.48.25438.76.48.255126
9938.76.49.0/2538.76.49.1 to 38.76.49.12638.76.49.127126
10038.76.49.128/2538.76.49.129 to 38.76.49.25438.76.49.255126
10138.76.50.0/2538.76.50.1 to 38.76.50.12638.76.50.127126
10238.76.50.128/2538.76.50.129 to 38.76.50.25438.76.50.255126
10338.76.51.0/2538.76.51.1 to 38.76.51.12638.76.51.127126
10438.76.51.128/2538.76.51.129 to 38.76.51.25438.76.51.255126
10538.76.52.0/2538.76.52.1 to 38.76.52.12638.76.52.127126
10638.76.52.128/2538.76.52.129 to 38.76.52.25438.76.52.255126
10738.76.53.0/2538.76.53.1 to 38.76.53.12638.76.53.127126
10838.76.53.128/2538.76.53.129 to 38.76.53.25438.76.53.255126
10938.76.54.0/2538.76.54.1 to 38.76.54.12638.76.54.127126
11038.76.54.128/2538.76.54.129 to 38.76.54.25438.76.54.255126
11138.76.55.0/2538.76.55.1 to 38.76.55.12638.76.55.127126
11238.76.55.128/2538.76.55.129 to 38.76.55.25438.76.55.255126
11338.76.56.0/2538.76.56.1 to 38.76.56.12638.76.56.127126
11438.76.56.128/2538.76.56.129 to 38.76.56.25438.76.56.255126
11538.76.57.0/2538.76.57.1 to 38.76.57.12638.76.57.127126
11638.76.57.128/2538.76.57.129 to 38.76.57.25438.76.57.255126
11738.76.58.0/2538.76.58.1 to 38.76.58.12638.76.58.127126
11838.76.58.128/2538.76.58.129 to 38.76.58.25438.76.58.255126
11938.76.59.0/2538.76.59.1 to 38.76.59.12638.76.59.127126
12038.76.59.128/2538.76.59.129 to 38.76.59.25438.76.59.255126
12138.76.60.0/2538.76.60.1 to 38.76.60.12638.76.60.127126
12238.76.60.128/2538.76.60.129 to 38.76.60.25438.76.60.255126
12338.76.61.0/2538.76.61.1 to 38.76.61.12638.76.61.127126
12438.76.61.128/2538.76.61.129 to 38.76.61.25438.76.61.255126
12538.76.62.0/2538.76.62.1 to 38.76.62.12638.76.62.127126
12638.76.62.128/2538.76.62.129 to 38.76.62.25438.76.62.255126
12738.76.63.0/2538.76.63.1 to 38.76.63.12638.76.63.127126
12838.76.63.128/2538.76.63.129 to 38.76.63.25438.76.63.255126
12938.76.64.0/2538.76.64.1 to 38.76.64.12638.76.64.127126
13038.76.64.128/2538.76.64.129 to 38.76.64.25438.76.64.255126
13138.76.65.0/2538.76.65.1 to 38.76.65.12638.76.65.127126
13238.76.65.128/2538.76.65.129 to 38.76.65.25438.76.65.255126
13338.76.66.0/2538.76.66.1 to 38.76.66.12638.76.66.127126
13438.76.66.128/2538.76.66.129 to 38.76.66.25438.76.66.255126
13538.76.67.0/2538.76.67.1 to 38.76.67.12638.76.67.127126
13638.76.67.128/2538.76.67.129 to 38.76.67.25438.76.67.255126
13738.76.68.0/2538.76.68.1 to 38.76.68.12638.76.68.127126
13838.76.68.128/2538.76.68.129 to 38.76.68.25438.76.68.255126
13938.76.69.0/2538.76.69.1 to 38.76.69.12638.76.69.127126
14038.76.69.128/2538.76.69.129 to 38.76.69.25438.76.69.255126
14138.76.70.0/2538.76.70.1 to 38.76.70.12638.76.70.127126
14238.76.70.128/2538.76.70.129 to 38.76.70.25438.76.70.255126
14338.76.71.0/2538.76.71.1 to 38.76.71.12638.76.71.127126
14438.76.71.128/2538.76.71.129 to 38.76.71.25438.76.71.255126
14538.76.72.0/2538.76.72.1 to 38.76.72.12638.76.72.127126
14638.76.72.128/2538.76.72.129 to 38.76.72.25438.76.72.255126
14738.76.73.0/2538.76.73.1 to 38.76.73.12638.76.73.127126
14838.76.73.128/2538.76.73.129 to 38.76.73.25438.76.73.255126
14938.76.74.0/2538.76.74.1 to 38.76.74.12638.76.74.127126
15038.76.74.128/2538.76.74.129 to 38.76.74.25438.76.74.255126
15138.76.75.0/2538.76.75.1 to 38.76.75.12638.76.75.127126
15238.76.75.128/2538.76.75.129 to 38.76.75.25438.76.75.255126
15338.76.76.0/2538.76.76.1 to 38.76.76.12638.76.76.127126
15438.76.76.128/2538.76.76.129 to 38.76.76.25438.76.76.255126
15538.76.77.0/2538.76.77.1 to 38.76.77.12638.76.77.127126
15638.76.77.128/2538.76.77.129 to 38.76.77.25438.76.77.255126
15738.76.78.0/2538.76.78.1 to 38.76.78.12638.76.78.127126
15838.76.78.128/2538.76.78.129 to 38.76.78.25438.76.78.255126
15938.76.79.0/2538.76.79.1 to 38.76.79.12638.76.79.127126
16038.76.79.128/2538.76.79.129 to 38.76.79.25438.76.79.255126
16138.76.80.0/2538.76.80.1 to 38.76.80.12638.76.80.127126
16238.76.80.128/2538.76.80.129 to 38.76.80.25438.76.80.255126
16338.76.81.0/2538.76.81.1 to 38.76.81.12638.76.81.127126
16438.76.81.128/2538.76.81.129 to 38.76.81.25438.76.81.255126
16538.76.82.0/2538.76.82.1 to 38.76.82.12638.76.82.127126
16638.76.82.128/2538.76.82.129 to 38.76.82.25438.76.82.255126
16738.76.83.0/2538.76.83.1 to 38.76.83.12638.76.83.127126
16838.76.83.128/2538.76.83.129 to 38.76.83.25438.76.83.255126
16938.76.84.0/2538.76.84.1 to 38.76.84.12638.76.84.127126
17038.76.84.128/2538.76.84.129 to 38.76.84.25438.76.84.255126
17138.76.85.0/2538.76.85.1 to 38.76.85.12638.76.85.127126
17238.76.85.128/2538.76.85.129 to 38.76.85.25438.76.85.255126
17338.76.86.0/2538.76.86.1 to 38.76.86.12638.76.86.127126
17438.76.86.128/2538.76.86.129 to 38.76.86.25438.76.86.255126
17538.76.87.0/2538.76.87.1 to 38.76.87.12638.76.87.127126
17638.76.87.128/2538.76.87.129 to 38.76.87.25438.76.87.255126
17738.76.88.0/2538.76.88.1 to 38.76.88.12638.76.88.127126
17838.76.88.128/2538.76.88.129 to 38.76.88.25438.76.88.255126
17938.76.89.0/2538.76.89.1 to 38.76.89.12638.76.89.127126
18038.76.89.128/2538.76.89.129 to 38.76.89.25438.76.89.255126
18138.76.90.0/2538.76.90.1 to 38.76.90.12638.76.90.127126
18238.76.90.128/2538.76.90.129 to 38.76.90.25438.76.90.255126
18338.76.91.0/2538.76.91.1 to 38.76.91.12638.76.91.127126
18438.76.91.128/2538.76.91.129 to 38.76.91.25438.76.91.255126
18538.76.92.0/2538.76.92.1 to 38.76.92.12638.76.92.127126
18638.76.92.128/2538.76.92.129 to 38.76.92.25438.76.92.255126
18738.76.93.0/2538.76.93.1 to 38.76.93.12638.76.93.127126
18838.76.93.128/2538.76.93.129 to 38.76.93.25438.76.93.255126
18938.76.94.0/2538.76.94.1 to 38.76.94.12638.76.94.127126
19038.76.94.128/2538.76.94.129 to 38.76.94.25438.76.94.255126
19138.76.95.0/2538.76.95.1 to 38.76.95.12638.76.95.127126
19238.76.95.128/2538.76.95.129 to 38.76.95.25438.76.95.255126
19338.76.96.0/2538.76.96.1 to 38.76.96.12638.76.96.127126
19438.76.96.128/2538.76.96.129 to 38.76.96.25438.76.96.255126
19538.76.97.0/2538.76.97.1 to 38.76.97.12638.76.97.127126
19638.76.97.128/2538.76.97.129 to 38.76.97.25438.76.97.255126
19738.76.98.0/2538.76.98.1 to 38.76.98.12638.76.98.127126
19838.76.98.128/2538.76.98.129 to 38.76.98.25438.76.98.255126
19938.76.99.0/2538.76.99.1 to 38.76.99.12638.76.99.127126
20038.76.99.128/2538.76.99.129 to 38.76.99.25438.76.99.255126
20138.76.100.0/2538.76.100.1 to 38.76.100.12638.76.100.127126
20238.76.100.128/2538.76.100.129 to 38.76.100.25438.76.100.255126
20338.76.101.0/2538.76.101.1 to 38.76.101.12638.76.101.127126
20438.76.101.128/2538.76.101.129 to 38.76.101.25438.76.101.255126
20538.76.102.0/2538.76.102.1 to 38.76.102.12638.76.102.127126
20638.76.102.128/2538.76.102.129 to 38.76.102.25438.76.102.255126
20738.76.103.0/2538.76.103.1 to 38.76.103.12638.76.103.127126
20838.76.103.128/2538.76.103.129 to 38.76.103.25438.76.103.255126
20938.76.104.0/2538.76.104.1 to 38.76.104.12638.76.104.127126
21038.76.104.128/2538.76.104.129 to 38.76.104.25438.76.104.255126
21138.76.105.0/2538.76.105.1 to 38.76.105.12638.76.105.127126
21238.76.105.128/2538.76.105.129 to 38.76.105.25438.76.105.255126
21338.76.106.0/2538.76.106.1 to 38.76.106.12638.76.106.127126
21438.76.106.128/2538.76.106.129 to 38.76.106.25438.76.106.255126
21538.76.107.0/2538.76.107.1 to 38.76.107.12638.76.107.127126
21638.76.107.128/2538.76.107.129 to 38.76.107.25438.76.107.255126
21738.76.108.0/2538.76.108.1 to 38.76.108.12638.76.108.127126
21838.76.108.128/2538.76.108.129 to 38.76.108.25438.76.108.255126
21938.76.109.0/2538.76.109.1 to 38.76.109.12638.76.109.127126
22038.76.109.128/2538.76.109.129 to 38.76.109.25438.76.109.255126
22138.76.110.0/2538.76.110.1 to 38.76.110.12638.76.110.127126
22238.76.110.128/2538.76.110.129 to 38.76.110.25438.76.110.255126
22338.76.111.0/2538.76.111.1 to 38.76.111.12638.76.111.127126
22438.76.111.128/2538.76.111.129 to 38.76.111.25438.76.111.255126
22538.76.112.0/2538.76.112.1 to 38.76.112.12638.76.112.127126
22638.76.112.128/2538.76.112.129 to 38.76.112.25438.76.112.255126
22738.76.113.0/2538.76.113.1 to 38.76.113.12638.76.113.127126
22838.76.113.128/2538.76.113.129 to 38.76.113.25438.76.113.255126
22938.76.114.0/2538.76.114.1 to 38.76.114.12638.76.114.127126
23038.76.114.128/2538.76.114.129 to 38.76.114.25438.76.114.255126
23138.76.115.0/2538.76.115.1 to 38.76.115.12638.76.115.127126
23238.76.115.128/2538.76.115.129 to 38.76.115.25438.76.115.255126
23338.76.116.0/2538.76.116.1 to 38.76.116.12638.76.116.127126
23438.76.116.128/2538.76.116.129 to 38.76.116.25438.76.116.255126
23538.76.117.0/2538.76.117.1 to 38.76.117.12638.76.117.127126
23638.76.117.128/2538.76.117.129 to 38.76.117.25438.76.117.255126
23738.76.118.0/2538.76.118.1 to 38.76.118.12638.76.118.127126
23838.76.118.128/2538.76.118.129 to 38.76.118.25438.76.118.255126
23938.76.119.0/2538.76.119.1 to 38.76.119.12638.76.119.127126
24038.76.119.128/2538.76.119.129 to 38.76.119.25438.76.119.255126
24138.76.120.0/2538.76.120.1 to 38.76.120.12638.76.120.127126
24238.76.120.128/2538.76.120.129 to 38.76.120.25438.76.120.255126
24338.76.121.0/2538.76.121.1 to 38.76.121.12638.76.121.127126
24438.76.121.128/2538.76.121.129 to 38.76.121.25438.76.121.255126
24538.76.122.0/2538.76.122.1 to 38.76.122.12638.76.122.127126
24638.76.122.128/2538.76.122.129 to 38.76.122.25438.76.122.255126
24738.76.123.0/2538.76.123.1 to 38.76.123.12638.76.123.127126
24838.76.123.128/2538.76.123.129 to 38.76.123.25438.76.123.255126
24938.76.124.0/2538.76.124.1 to 38.76.124.12638.76.124.127126
25038.76.124.128/2538.76.124.129 to 38.76.124.25438.76.124.255126
25138.76.125.0/2538.76.125.1 to 38.76.125.12638.76.125.127126
25238.76.125.128/2538.76.125.129 to 38.76.125.25438.76.125.255126
25338.76.126.0/2538.76.126.1 to 38.76.126.12638.76.126.127126
25438.76.126.128/2538.76.126.129 to 38.76.126.25438.76.126.255126
25538.76.127.0/2538.76.127.1 to 38.76.127.12638.76.127.127126
25638.76.127.128/2538.76.127.129 to 38.76.127.25438.76.127.255126

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