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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.

Network92.0.0.0/9
Usable hosts8,388,606
Subnet mask255.128.0.0
Addresses8,388,608
Network address
92.0.0.0
Broadcast address
92.127.255.255
First usable
92.0.0.1
Last usable
92.127.255.254
Usable hosts
8,388,606 (8,388,608 less the network and broadcast addresses)
Subnet mask
255.128.0.0
Wildcard mask
0.127.255.255 (Cisco ACLs, OSPF)
Prefix length
/9
Type
Public public
Old class
A (default /8)
As numbers
Hex 5C000000 · Integer 1543503872 to 1551892479
Reverse DNS zones
0.92.in-addr.arpa
1.92.in-addr.arpa
2.92.in-addr.arpa
3.92.in-addr.arpa
4.92.in-addr.arpa
5.92.in-addr.arpa
6.92.in-addr.arpa
7.92.in-addr.arpa
8.92.in-addr.arpa
9.92.in-addr.arpa
10.92.in-addr.arpa
11.92.in-addr.arpa
12.92.in-addr.arpa
13.92.in-addr.arpa
14.92.in-addr.arpa
15.92.in-addr.arpa
and 112 more
/9 is not on a 8-bit boundary, so it takes 128 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011100.00000000.00000000.0000000092.0.0.0
Subnet mask11111111.10000000.00000000.00000000255.128.0.0
Network01011100.00000000.00000000.0000000092.0.0.0
Broadcast01011100.01111111.11111111.1111111192.127.255.255
Split into smaller subnets/17
/10 (2)/11 (4)/12 (8)/13 (16)/14 (32)/15 (64)/16 (128)/17 (256)/18 (512)/19 (1,024)/20 (2,048)/21 (4,096)

92.0.0.0/9 makes 256 subnets of /17.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
192.0.0.0/1792.0.0.1 to 92.0.127.25492.0.127.25532,766
292.0.128.0/1792.0.128.1 to 92.0.255.25492.0.255.25532,766
392.1.0.0/1792.1.0.1 to 92.1.127.25492.1.127.25532,766
492.1.128.0/1792.1.128.1 to 92.1.255.25492.1.255.25532,766
592.2.0.0/1792.2.0.1 to 92.2.127.25492.2.127.25532,766
692.2.128.0/1792.2.128.1 to 92.2.255.25492.2.255.25532,766
792.3.0.0/1792.3.0.1 to 92.3.127.25492.3.127.25532,766
892.3.128.0/1792.3.128.1 to 92.3.255.25492.3.255.25532,766
992.4.0.0/1792.4.0.1 to 92.4.127.25492.4.127.25532,766
1092.4.128.0/1792.4.128.1 to 92.4.255.25492.4.255.25532,766
1192.5.0.0/1792.5.0.1 to 92.5.127.25492.5.127.25532,766
1292.5.128.0/1792.5.128.1 to 92.5.255.25492.5.255.25532,766
1392.6.0.0/1792.6.0.1 to 92.6.127.25492.6.127.25532,766
1492.6.128.0/1792.6.128.1 to 92.6.255.25492.6.255.25532,766
1592.7.0.0/1792.7.0.1 to 92.7.127.25492.7.127.25532,766
1692.7.128.0/1792.7.128.1 to 92.7.255.25492.7.255.25532,766
1792.8.0.0/1792.8.0.1 to 92.8.127.25492.8.127.25532,766
1892.8.128.0/1792.8.128.1 to 92.8.255.25492.8.255.25532,766
1992.9.0.0/1792.9.0.1 to 92.9.127.25492.9.127.25532,766
2092.9.128.0/1792.9.128.1 to 92.9.255.25492.9.255.25532,766
2192.10.0.0/1792.10.0.1 to 92.10.127.25492.10.127.25532,766
2292.10.128.0/1792.10.128.1 to 92.10.255.25492.10.255.25532,766
2392.11.0.0/1792.11.0.1 to 92.11.127.25492.11.127.25532,766
2492.11.128.0/1792.11.128.1 to 92.11.255.25492.11.255.25532,766
2592.12.0.0/1792.12.0.1 to 92.12.127.25492.12.127.25532,766
2692.12.128.0/1792.12.128.1 to 92.12.255.25492.12.255.25532,766
2792.13.0.0/1792.13.0.1 to 92.13.127.25492.13.127.25532,766
2892.13.128.0/1792.13.128.1 to 92.13.255.25492.13.255.25532,766
2992.14.0.0/1792.14.0.1 to 92.14.127.25492.14.127.25532,766
3092.14.128.0/1792.14.128.1 to 92.14.255.25492.14.255.25532,766
3192.15.0.0/1792.15.0.1 to 92.15.127.25492.15.127.25532,766
3292.15.128.0/1792.15.128.1 to 92.15.255.25492.15.255.25532,766
3392.16.0.0/1792.16.0.1 to 92.16.127.25492.16.127.25532,766
3492.16.128.0/1792.16.128.1 to 92.16.255.25492.16.255.25532,766
3592.17.0.0/1792.17.0.1 to 92.17.127.25492.17.127.25532,766
3692.17.128.0/1792.17.128.1 to 92.17.255.25492.17.255.25532,766
3792.18.0.0/1792.18.0.1 to 92.18.127.25492.18.127.25532,766
3892.18.128.0/1792.18.128.1 to 92.18.255.25492.18.255.25532,766
3992.19.0.0/1792.19.0.1 to 92.19.127.25492.19.127.25532,766
4092.19.128.0/1792.19.128.1 to 92.19.255.25492.19.255.25532,766
4192.20.0.0/1792.20.0.1 to 92.20.127.25492.20.127.25532,766
4292.20.128.0/1792.20.128.1 to 92.20.255.25492.20.255.25532,766
4392.21.0.0/1792.21.0.1 to 92.21.127.25492.21.127.25532,766
4492.21.128.0/1792.21.128.1 to 92.21.255.25492.21.255.25532,766
4592.22.0.0/1792.22.0.1 to 92.22.127.25492.22.127.25532,766
4692.22.128.0/1792.22.128.1 to 92.22.255.25492.22.255.25532,766
4792.23.0.0/1792.23.0.1 to 92.23.127.25492.23.127.25532,766
4892.23.128.0/1792.23.128.1 to 92.23.255.25492.23.255.25532,766
4992.24.0.0/1792.24.0.1 to 92.24.127.25492.24.127.25532,766
5092.24.128.0/1792.24.128.1 to 92.24.255.25492.24.255.25532,766
5192.25.0.0/1792.25.0.1 to 92.25.127.25492.25.127.25532,766
5292.25.128.0/1792.25.128.1 to 92.25.255.25492.25.255.25532,766
5392.26.0.0/1792.26.0.1 to 92.26.127.25492.26.127.25532,766
5492.26.128.0/1792.26.128.1 to 92.26.255.25492.26.255.25532,766
5592.27.0.0/1792.27.0.1 to 92.27.127.25492.27.127.25532,766
5692.27.128.0/1792.27.128.1 to 92.27.255.25492.27.255.25532,766
5792.28.0.0/1792.28.0.1 to 92.28.127.25492.28.127.25532,766
5892.28.128.0/1792.28.128.1 to 92.28.255.25492.28.255.25532,766
5992.29.0.0/1792.29.0.1 to 92.29.127.25492.29.127.25532,766
6092.29.128.0/1792.29.128.1 to 92.29.255.25492.29.255.25532,766
6192.30.0.0/1792.30.0.1 to 92.30.127.25492.30.127.25532,766
6292.30.128.0/1792.30.128.1 to 92.30.255.25492.30.255.25532,766
6392.31.0.0/1792.31.0.1 to 92.31.127.25492.31.127.25532,766
6492.31.128.0/1792.31.128.1 to 92.31.255.25492.31.255.25532,766
6592.32.0.0/1792.32.0.1 to 92.32.127.25492.32.127.25532,766
6692.32.128.0/1792.32.128.1 to 92.32.255.25492.32.255.25532,766
6792.33.0.0/1792.33.0.1 to 92.33.127.25492.33.127.25532,766
6892.33.128.0/1792.33.128.1 to 92.33.255.25492.33.255.25532,766
6992.34.0.0/1792.34.0.1 to 92.34.127.25492.34.127.25532,766
7092.34.128.0/1792.34.128.1 to 92.34.255.25492.34.255.25532,766
7192.35.0.0/1792.35.0.1 to 92.35.127.25492.35.127.25532,766
7292.35.128.0/1792.35.128.1 to 92.35.255.25492.35.255.25532,766
7392.36.0.0/1792.36.0.1 to 92.36.127.25492.36.127.25532,766
7492.36.128.0/1792.36.128.1 to 92.36.255.25492.36.255.25532,766
7592.37.0.0/1792.37.0.1 to 92.37.127.25492.37.127.25532,766
7692.37.128.0/1792.37.128.1 to 92.37.255.25492.37.255.25532,766
7792.38.0.0/1792.38.0.1 to 92.38.127.25492.38.127.25532,766
7892.38.128.0/1792.38.128.1 to 92.38.255.25492.38.255.25532,766
7992.39.0.0/1792.39.0.1 to 92.39.127.25492.39.127.25532,766
8092.39.128.0/1792.39.128.1 to 92.39.255.25492.39.255.25532,766
8192.40.0.0/1792.40.0.1 to 92.40.127.25492.40.127.25532,766
8292.40.128.0/1792.40.128.1 to 92.40.255.25492.40.255.25532,766
8392.41.0.0/1792.41.0.1 to 92.41.127.25492.41.127.25532,766
8492.41.128.0/1792.41.128.1 to 92.41.255.25492.41.255.25532,766
8592.42.0.0/1792.42.0.1 to 92.42.127.25492.42.127.25532,766
8692.42.128.0/1792.42.128.1 to 92.42.255.25492.42.255.25532,766
8792.43.0.0/1792.43.0.1 to 92.43.127.25492.43.127.25532,766
8892.43.128.0/1792.43.128.1 to 92.43.255.25492.43.255.25532,766
8992.44.0.0/1792.44.0.1 to 92.44.127.25492.44.127.25532,766
9092.44.128.0/1792.44.128.1 to 92.44.255.25492.44.255.25532,766
9192.45.0.0/1792.45.0.1 to 92.45.127.25492.45.127.25532,766
9292.45.128.0/1792.45.128.1 to 92.45.255.25492.45.255.25532,766
9392.46.0.0/1792.46.0.1 to 92.46.127.25492.46.127.25532,766
9492.46.128.0/1792.46.128.1 to 92.46.255.25492.46.255.25532,766
9592.47.0.0/1792.47.0.1 to 92.47.127.25492.47.127.25532,766
9692.47.128.0/1792.47.128.1 to 92.47.255.25492.47.255.25532,766
9792.48.0.0/1792.48.0.1 to 92.48.127.25492.48.127.25532,766
9892.48.128.0/1792.48.128.1 to 92.48.255.25492.48.255.25532,766
9992.49.0.0/1792.49.0.1 to 92.49.127.25492.49.127.25532,766
10092.49.128.0/1792.49.128.1 to 92.49.255.25492.49.255.25532,766
10192.50.0.0/1792.50.0.1 to 92.50.127.25492.50.127.25532,766
10292.50.128.0/1792.50.128.1 to 92.50.255.25492.50.255.25532,766
10392.51.0.0/1792.51.0.1 to 92.51.127.25492.51.127.25532,766
10492.51.128.0/1792.51.128.1 to 92.51.255.25492.51.255.25532,766
10592.52.0.0/1792.52.0.1 to 92.52.127.25492.52.127.25532,766
10692.52.128.0/1792.52.128.1 to 92.52.255.25492.52.255.25532,766
10792.53.0.0/1792.53.0.1 to 92.53.127.25492.53.127.25532,766
10892.53.128.0/1792.53.128.1 to 92.53.255.25492.53.255.25532,766
10992.54.0.0/1792.54.0.1 to 92.54.127.25492.54.127.25532,766
11092.54.128.0/1792.54.128.1 to 92.54.255.25492.54.255.25532,766
11192.55.0.0/1792.55.0.1 to 92.55.127.25492.55.127.25532,766
11292.55.128.0/1792.55.128.1 to 92.55.255.25492.55.255.25532,766
11392.56.0.0/1792.56.0.1 to 92.56.127.25492.56.127.25532,766
11492.56.128.0/1792.56.128.1 to 92.56.255.25492.56.255.25532,766
11592.57.0.0/1792.57.0.1 to 92.57.127.25492.57.127.25532,766
11692.57.128.0/1792.57.128.1 to 92.57.255.25492.57.255.25532,766
11792.58.0.0/1792.58.0.1 to 92.58.127.25492.58.127.25532,766
11892.58.128.0/1792.58.128.1 to 92.58.255.25492.58.255.25532,766
11992.59.0.0/1792.59.0.1 to 92.59.127.25492.59.127.25532,766
12092.59.128.0/1792.59.128.1 to 92.59.255.25492.59.255.25532,766
12192.60.0.0/1792.60.0.1 to 92.60.127.25492.60.127.25532,766
12292.60.128.0/1792.60.128.1 to 92.60.255.25492.60.255.25532,766
12392.61.0.0/1792.61.0.1 to 92.61.127.25492.61.127.25532,766
12492.61.128.0/1792.61.128.1 to 92.61.255.25492.61.255.25532,766
12592.62.0.0/1792.62.0.1 to 92.62.127.25492.62.127.25532,766
12692.62.128.0/1792.62.128.1 to 92.62.255.25492.62.255.25532,766
12792.63.0.0/1792.63.0.1 to 92.63.127.25492.63.127.25532,766
12892.63.128.0/1792.63.128.1 to 92.63.255.25492.63.255.25532,766
12992.64.0.0/1792.64.0.1 to 92.64.127.25492.64.127.25532,766
13092.64.128.0/1792.64.128.1 to 92.64.255.25492.64.255.25532,766
13192.65.0.0/1792.65.0.1 to 92.65.127.25492.65.127.25532,766
13292.65.128.0/1792.65.128.1 to 92.65.255.25492.65.255.25532,766
13392.66.0.0/1792.66.0.1 to 92.66.127.25492.66.127.25532,766
13492.66.128.0/1792.66.128.1 to 92.66.255.25492.66.255.25532,766
13592.67.0.0/1792.67.0.1 to 92.67.127.25492.67.127.25532,766
13692.67.128.0/1792.67.128.1 to 92.67.255.25492.67.255.25532,766
13792.68.0.0/1792.68.0.1 to 92.68.127.25492.68.127.25532,766
13892.68.128.0/1792.68.128.1 to 92.68.255.25492.68.255.25532,766
13992.69.0.0/1792.69.0.1 to 92.69.127.25492.69.127.25532,766
14092.69.128.0/1792.69.128.1 to 92.69.255.25492.69.255.25532,766
14192.70.0.0/1792.70.0.1 to 92.70.127.25492.70.127.25532,766
14292.70.128.0/1792.70.128.1 to 92.70.255.25492.70.255.25532,766
14392.71.0.0/1792.71.0.1 to 92.71.127.25492.71.127.25532,766
14492.71.128.0/1792.71.128.1 to 92.71.255.25492.71.255.25532,766
14592.72.0.0/1792.72.0.1 to 92.72.127.25492.72.127.25532,766
14692.72.128.0/1792.72.128.1 to 92.72.255.25492.72.255.25532,766
14792.73.0.0/1792.73.0.1 to 92.73.127.25492.73.127.25532,766
14892.73.128.0/1792.73.128.1 to 92.73.255.25492.73.255.25532,766
14992.74.0.0/1792.74.0.1 to 92.74.127.25492.74.127.25532,766
15092.74.128.0/1792.74.128.1 to 92.74.255.25492.74.255.25532,766
15192.75.0.0/1792.75.0.1 to 92.75.127.25492.75.127.25532,766
15292.75.128.0/1792.75.128.1 to 92.75.255.25492.75.255.25532,766
15392.76.0.0/1792.76.0.1 to 92.76.127.25492.76.127.25532,766
15492.76.128.0/1792.76.128.1 to 92.76.255.25492.76.255.25532,766
15592.77.0.0/1792.77.0.1 to 92.77.127.25492.77.127.25532,766
15692.77.128.0/1792.77.128.1 to 92.77.255.25492.77.255.25532,766
15792.78.0.0/1792.78.0.1 to 92.78.127.25492.78.127.25532,766
15892.78.128.0/1792.78.128.1 to 92.78.255.25492.78.255.25532,766
15992.79.0.0/1792.79.0.1 to 92.79.127.25492.79.127.25532,766
16092.79.128.0/1792.79.128.1 to 92.79.255.25492.79.255.25532,766
16192.80.0.0/1792.80.0.1 to 92.80.127.25492.80.127.25532,766
16292.80.128.0/1792.80.128.1 to 92.80.255.25492.80.255.25532,766
16392.81.0.0/1792.81.0.1 to 92.81.127.25492.81.127.25532,766
16492.81.128.0/1792.81.128.1 to 92.81.255.25492.81.255.25532,766
16592.82.0.0/1792.82.0.1 to 92.82.127.25492.82.127.25532,766
16692.82.128.0/1792.82.128.1 to 92.82.255.25492.82.255.25532,766
16792.83.0.0/1792.83.0.1 to 92.83.127.25492.83.127.25532,766
16892.83.128.0/1792.83.128.1 to 92.83.255.25492.83.255.25532,766
16992.84.0.0/1792.84.0.1 to 92.84.127.25492.84.127.25532,766
17092.84.128.0/1792.84.128.1 to 92.84.255.25492.84.255.25532,766
17192.85.0.0/1792.85.0.1 to 92.85.127.25492.85.127.25532,766
17292.85.128.0/1792.85.128.1 to 92.85.255.25492.85.255.25532,766
17392.86.0.0/1792.86.0.1 to 92.86.127.25492.86.127.25532,766
17492.86.128.0/1792.86.128.1 to 92.86.255.25492.86.255.25532,766
17592.87.0.0/1792.87.0.1 to 92.87.127.25492.87.127.25532,766
17692.87.128.0/1792.87.128.1 to 92.87.255.25492.87.255.25532,766
17792.88.0.0/1792.88.0.1 to 92.88.127.25492.88.127.25532,766
17892.88.128.0/1792.88.128.1 to 92.88.255.25492.88.255.25532,766
17992.89.0.0/1792.89.0.1 to 92.89.127.25492.89.127.25532,766
18092.89.128.0/1792.89.128.1 to 92.89.255.25492.89.255.25532,766
18192.90.0.0/1792.90.0.1 to 92.90.127.25492.90.127.25532,766
18292.90.128.0/1792.90.128.1 to 92.90.255.25492.90.255.25532,766
18392.91.0.0/1792.91.0.1 to 92.91.127.25492.91.127.25532,766
18492.91.128.0/1792.91.128.1 to 92.91.255.25492.91.255.25532,766
18592.92.0.0/1792.92.0.1 to 92.92.127.25492.92.127.25532,766
18692.92.128.0/1792.92.128.1 to 92.92.255.25492.92.255.25532,766
18792.93.0.0/1792.93.0.1 to 92.93.127.25492.93.127.25532,766
18892.93.128.0/1792.93.128.1 to 92.93.255.25492.93.255.25532,766
18992.94.0.0/1792.94.0.1 to 92.94.127.25492.94.127.25532,766
19092.94.128.0/1792.94.128.1 to 92.94.255.25492.94.255.25532,766
19192.95.0.0/1792.95.0.1 to 92.95.127.25492.95.127.25532,766
19292.95.128.0/1792.95.128.1 to 92.95.255.25492.95.255.25532,766
19392.96.0.0/1792.96.0.1 to 92.96.127.25492.96.127.25532,766
19492.96.128.0/1792.96.128.1 to 92.96.255.25492.96.255.25532,766
19592.97.0.0/1792.97.0.1 to 92.97.127.25492.97.127.25532,766
19692.97.128.0/1792.97.128.1 to 92.97.255.25492.97.255.25532,766
19792.98.0.0/1792.98.0.1 to 92.98.127.25492.98.127.25532,766
19892.98.128.0/1792.98.128.1 to 92.98.255.25492.98.255.25532,766
19992.99.0.0/1792.99.0.1 to 92.99.127.25492.99.127.25532,766
20092.99.128.0/1792.99.128.1 to 92.99.255.25492.99.255.25532,766
20192.100.0.0/1792.100.0.1 to 92.100.127.25492.100.127.25532,766
20292.100.128.0/1792.100.128.1 to 92.100.255.25492.100.255.25532,766
20392.101.0.0/1792.101.0.1 to 92.101.127.25492.101.127.25532,766
20492.101.128.0/1792.101.128.1 to 92.101.255.25492.101.255.25532,766
20592.102.0.0/1792.102.0.1 to 92.102.127.25492.102.127.25532,766
20692.102.128.0/1792.102.128.1 to 92.102.255.25492.102.255.25532,766
20792.103.0.0/1792.103.0.1 to 92.103.127.25492.103.127.25532,766
20892.103.128.0/1792.103.128.1 to 92.103.255.25492.103.255.25532,766
20992.104.0.0/1792.104.0.1 to 92.104.127.25492.104.127.25532,766
21092.104.128.0/1792.104.128.1 to 92.104.255.25492.104.255.25532,766
21192.105.0.0/1792.105.0.1 to 92.105.127.25492.105.127.25532,766
21292.105.128.0/1792.105.128.1 to 92.105.255.25492.105.255.25532,766
21392.106.0.0/1792.106.0.1 to 92.106.127.25492.106.127.25532,766
21492.106.128.0/1792.106.128.1 to 92.106.255.25492.106.255.25532,766
21592.107.0.0/1792.107.0.1 to 92.107.127.25492.107.127.25532,766
21692.107.128.0/1792.107.128.1 to 92.107.255.25492.107.255.25532,766
21792.108.0.0/1792.108.0.1 to 92.108.127.25492.108.127.25532,766
21892.108.128.0/1792.108.128.1 to 92.108.255.25492.108.255.25532,766
21992.109.0.0/1792.109.0.1 to 92.109.127.25492.109.127.25532,766
22092.109.128.0/1792.109.128.1 to 92.109.255.25492.109.255.25532,766
22192.110.0.0/1792.110.0.1 to 92.110.127.25492.110.127.25532,766
22292.110.128.0/1792.110.128.1 to 92.110.255.25492.110.255.25532,766
22392.111.0.0/1792.111.0.1 to 92.111.127.25492.111.127.25532,766
22492.111.128.0/1792.111.128.1 to 92.111.255.25492.111.255.25532,766
22592.112.0.0/1792.112.0.1 to 92.112.127.25492.112.127.25532,766
22692.112.128.0/1792.112.128.1 to 92.112.255.25492.112.255.25532,766
22792.113.0.0/1792.113.0.1 to 92.113.127.25492.113.127.25532,766
22892.113.128.0/1792.113.128.1 to 92.113.255.25492.113.255.25532,766
22992.114.0.0/1792.114.0.1 to 92.114.127.25492.114.127.25532,766
23092.114.128.0/1792.114.128.1 to 92.114.255.25492.114.255.25532,766
23192.115.0.0/1792.115.0.1 to 92.115.127.25492.115.127.25532,766
23292.115.128.0/1792.115.128.1 to 92.115.255.25492.115.255.25532,766
23392.116.0.0/1792.116.0.1 to 92.116.127.25492.116.127.25532,766
23492.116.128.0/1792.116.128.1 to 92.116.255.25492.116.255.25532,766
23592.117.0.0/1792.117.0.1 to 92.117.127.25492.117.127.25532,766
23692.117.128.0/1792.117.128.1 to 92.117.255.25492.117.255.25532,766
23792.118.0.0/1792.118.0.1 to 92.118.127.25492.118.127.25532,766
23892.118.128.0/1792.118.128.1 to 92.118.255.25492.118.255.25532,766
23992.119.0.0/1792.119.0.1 to 92.119.127.25492.119.127.25532,766
24092.119.128.0/1792.119.128.1 to 92.119.255.25492.119.255.25532,766
24192.120.0.0/1792.120.0.1 to 92.120.127.25492.120.127.25532,766
24292.120.128.0/1792.120.128.1 to 92.120.255.25492.120.255.25532,766
24392.121.0.0/1792.121.0.1 to 92.121.127.25492.121.127.25532,766
24492.121.128.0/1792.121.128.1 to 92.121.255.25492.121.255.25532,766
24592.122.0.0/1792.122.0.1 to 92.122.127.25492.122.127.25532,766
24692.122.128.0/1792.122.128.1 to 92.122.255.25492.122.255.25532,766
24792.123.0.0/1792.123.0.1 to 92.123.127.25492.123.127.25532,766
24892.123.128.0/1792.123.128.1 to 92.123.255.25492.123.255.25532,766
24992.124.0.0/1792.124.0.1 to 92.124.127.25492.124.127.25532,766
25092.124.128.0/1792.124.128.1 to 92.124.255.25492.124.255.25532,766
25192.125.0.0/1792.125.0.1 to 92.125.127.25492.125.127.25532,766
25292.125.128.0/1792.125.128.1 to 92.125.255.25492.125.255.25532,766
25392.126.0.0/1792.126.0.1 to 92.126.127.25492.126.127.25532,766
25492.126.128.0/1792.126.128.1 to 92.126.255.25492.126.255.25532,766
25592.127.0.0/1792.127.0.1 to 92.127.127.25492.127.127.25532,766
25692.127.128.0/1792.127.128.1 to 92.127.255.25492.127.255.25532,766

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.