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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/18
/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 512 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
192.0.0.0/1892.0.0.1 to 92.0.63.25492.0.63.25516,382
292.0.64.0/1892.0.64.1 to 92.0.127.25492.0.127.25516,382
392.0.128.0/1892.0.128.1 to 92.0.191.25492.0.191.25516,382
492.0.192.0/1892.0.192.1 to 92.0.255.25492.0.255.25516,382
592.1.0.0/1892.1.0.1 to 92.1.63.25492.1.63.25516,382
692.1.64.0/1892.1.64.1 to 92.1.127.25492.1.127.25516,382
792.1.128.0/1892.1.128.1 to 92.1.191.25492.1.191.25516,382
892.1.192.0/1892.1.192.1 to 92.1.255.25492.1.255.25516,382
992.2.0.0/1892.2.0.1 to 92.2.63.25492.2.63.25516,382
1092.2.64.0/1892.2.64.1 to 92.2.127.25492.2.127.25516,382
1192.2.128.0/1892.2.128.1 to 92.2.191.25492.2.191.25516,382
1292.2.192.0/1892.2.192.1 to 92.2.255.25492.2.255.25516,382
1392.3.0.0/1892.3.0.1 to 92.3.63.25492.3.63.25516,382
1492.3.64.0/1892.3.64.1 to 92.3.127.25492.3.127.25516,382
1592.3.128.0/1892.3.128.1 to 92.3.191.25492.3.191.25516,382
1692.3.192.0/1892.3.192.1 to 92.3.255.25492.3.255.25516,382
1792.4.0.0/1892.4.0.1 to 92.4.63.25492.4.63.25516,382
1892.4.64.0/1892.4.64.1 to 92.4.127.25492.4.127.25516,382
1992.4.128.0/1892.4.128.1 to 92.4.191.25492.4.191.25516,382
2092.4.192.0/1892.4.192.1 to 92.4.255.25492.4.255.25516,382
2192.5.0.0/1892.5.0.1 to 92.5.63.25492.5.63.25516,382
2292.5.64.0/1892.5.64.1 to 92.5.127.25492.5.127.25516,382
2392.5.128.0/1892.5.128.1 to 92.5.191.25492.5.191.25516,382
2492.5.192.0/1892.5.192.1 to 92.5.255.25492.5.255.25516,382
2592.6.0.0/1892.6.0.1 to 92.6.63.25492.6.63.25516,382
2692.6.64.0/1892.6.64.1 to 92.6.127.25492.6.127.25516,382
2792.6.128.0/1892.6.128.1 to 92.6.191.25492.6.191.25516,382
2892.6.192.0/1892.6.192.1 to 92.6.255.25492.6.255.25516,382
2992.7.0.0/1892.7.0.1 to 92.7.63.25492.7.63.25516,382
3092.7.64.0/1892.7.64.1 to 92.7.127.25492.7.127.25516,382
3192.7.128.0/1892.7.128.1 to 92.7.191.25492.7.191.25516,382
3292.7.192.0/1892.7.192.1 to 92.7.255.25492.7.255.25516,382
3392.8.0.0/1892.8.0.1 to 92.8.63.25492.8.63.25516,382
3492.8.64.0/1892.8.64.1 to 92.8.127.25492.8.127.25516,382
3592.8.128.0/1892.8.128.1 to 92.8.191.25492.8.191.25516,382
3692.8.192.0/1892.8.192.1 to 92.8.255.25492.8.255.25516,382
3792.9.0.0/1892.9.0.1 to 92.9.63.25492.9.63.25516,382
3892.9.64.0/1892.9.64.1 to 92.9.127.25492.9.127.25516,382
3992.9.128.0/1892.9.128.1 to 92.9.191.25492.9.191.25516,382
4092.9.192.0/1892.9.192.1 to 92.9.255.25492.9.255.25516,382
4192.10.0.0/1892.10.0.1 to 92.10.63.25492.10.63.25516,382
4292.10.64.0/1892.10.64.1 to 92.10.127.25492.10.127.25516,382
4392.10.128.0/1892.10.128.1 to 92.10.191.25492.10.191.25516,382
4492.10.192.0/1892.10.192.1 to 92.10.255.25492.10.255.25516,382
4592.11.0.0/1892.11.0.1 to 92.11.63.25492.11.63.25516,382
4692.11.64.0/1892.11.64.1 to 92.11.127.25492.11.127.25516,382
4792.11.128.0/1892.11.128.1 to 92.11.191.25492.11.191.25516,382
4892.11.192.0/1892.11.192.1 to 92.11.255.25492.11.255.25516,382
4992.12.0.0/1892.12.0.1 to 92.12.63.25492.12.63.25516,382
5092.12.64.0/1892.12.64.1 to 92.12.127.25492.12.127.25516,382
5192.12.128.0/1892.12.128.1 to 92.12.191.25492.12.191.25516,382
5292.12.192.0/1892.12.192.1 to 92.12.255.25492.12.255.25516,382
5392.13.0.0/1892.13.0.1 to 92.13.63.25492.13.63.25516,382
5492.13.64.0/1892.13.64.1 to 92.13.127.25492.13.127.25516,382
5592.13.128.0/1892.13.128.1 to 92.13.191.25492.13.191.25516,382
5692.13.192.0/1892.13.192.1 to 92.13.255.25492.13.255.25516,382
5792.14.0.0/1892.14.0.1 to 92.14.63.25492.14.63.25516,382
5892.14.64.0/1892.14.64.1 to 92.14.127.25492.14.127.25516,382
5992.14.128.0/1892.14.128.1 to 92.14.191.25492.14.191.25516,382
6092.14.192.0/1892.14.192.1 to 92.14.255.25492.14.255.25516,382
6192.15.0.0/1892.15.0.1 to 92.15.63.25492.15.63.25516,382
6292.15.64.0/1892.15.64.1 to 92.15.127.25492.15.127.25516,382
6392.15.128.0/1892.15.128.1 to 92.15.191.25492.15.191.25516,382
6492.15.192.0/1892.15.192.1 to 92.15.255.25492.15.255.25516,382
6592.16.0.0/1892.16.0.1 to 92.16.63.25492.16.63.25516,382
6692.16.64.0/1892.16.64.1 to 92.16.127.25492.16.127.25516,382
6792.16.128.0/1892.16.128.1 to 92.16.191.25492.16.191.25516,382
6892.16.192.0/1892.16.192.1 to 92.16.255.25492.16.255.25516,382
6992.17.0.0/1892.17.0.1 to 92.17.63.25492.17.63.25516,382
7092.17.64.0/1892.17.64.1 to 92.17.127.25492.17.127.25516,382
7192.17.128.0/1892.17.128.1 to 92.17.191.25492.17.191.25516,382
7292.17.192.0/1892.17.192.1 to 92.17.255.25492.17.255.25516,382
7392.18.0.0/1892.18.0.1 to 92.18.63.25492.18.63.25516,382
7492.18.64.0/1892.18.64.1 to 92.18.127.25492.18.127.25516,382
7592.18.128.0/1892.18.128.1 to 92.18.191.25492.18.191.25516,382
7692.18.192.0/1892.18.192.1 to 92.18.255.25492.18.255.25516,382
7792.19.0.0/1892.19.0.1 to 92.19.63.25492.19.63.25516,382
7892.19.64.0/1892.19.64.1 to 92.19.127.25492.19.127.25516,382
7992.19.128.0/1892.19.128.1 to 92.19.191.25492.19.191.25516,382
8092.19.192.0/1892.19.192.1 to 92.19.255.25492.19.255.25516,382
8192.20.0.0/1892.20.0.1 to 92.20.63.25492.20.63.25516,382
8292.20.64.0/1892.20.64.1 to 92.20.127.25492.20.127.25516,382
8392.20.128.0/1892.20.128.1 to 92.20.191.25492.20.191.25516,382
8492.20.192.0/1892.20.192.1 to 92.20.255.25492.20.255.25516,382
8592.21.0.0/1892.21.0.1 to 92.21.63.25492.21.63.25516,382
8692.21.64.0/1892.21.64.1 to 92.21.127.25492.21.127.25516,382
8792.21.128.0/1892.21.128.1 to 92.21.191.25492.21.191.25516,382
8892.21.192.0/1892.21.192.1 to 92.21.255.25492.21.255.25516,382
8992.22.0.0/1892.22.0.1 to 92.22.63.25492.22.63.25516,382
9092.22.64.0/1892.22.64.1 to 92.22.127.25492.22.127.25516,382
9192.22.128.0/1892.22.128.1 to 92.22.191.25492.22.191.25516,382
9292.22.192.0/1892.22.192.1 to 92.22.255.25492.22.255.25516,382
9392.23.0.0/1892.23.0.1 to 92.23.63.25492.23.63.25516,382
9492.23.64.0/1892.23.64.1 to 92.23.127.25492.23.127.25516,382
9592.23.128.0/1892.23.128.1 to 92.23.191.25492.23.191.25516,382
9692.23.192.0/1892.23.192.1 to 92.23.255.25492.23.255.25516,382
9792.24.0.0/1892.24.0.1 to 92.24.63.25492.24.63.25516,382
9892.24.64.0/1892.24.64.1 to 92.24.127.25492.24.127.25516,382
9992.24.128.0/1892.24.128.1 to 92.24.191.25492.24.191.25516,382
10092.24.192.0/1892.24.192.1 to 92.24.255.25492.24.255.25516,382
10192.25.0.0/1892.25.0.1 to 92.25.63.25492.25.63.25516,382
10292.25.64.0/1892.25.64.1 to 92.25.127.25492.25.127.25516,382
10392.25.128.0/1892.25.128.1 to 92.25.191.25492.25.191.25516,382
10492.25.192.0/1892.25.192.1 to 92.25.255.25492.25.255.25516,382
10592.26.0.0/1892.26.0.1 to 92.26.63.25492.26.63.25516,382
10692.26.64.0/1892.26.64.1 to 92.26.127.25492.26.127.25516,382
10792.26.128.0/1892.26.128.1 to 92.26.191.25492.26.191.25516,382
10892.26.192.0/1892.26.192.1 to 92.26.255.25492.26.255.25516,382
10992.27.0.0/1892.27.0.1 to 92.27.63.25492.27.63.25516,382
11092.27.64.0/1892.27.64.1 to 92.27.127.25492.27.127.25516,382
11192.27.128.0/1892.27.128.1 to 92.27.191.25492.27.191.25516,382
11292.27.192.0/1892.27.192.1 to 92.27.255.25492.27.255.25516,382
11392.28.0.0/1892.28.0.1 to 92.28.63.25492.28.63.25516,382
11492.28.64.0/1892.28.64.1 to 92.28.127.25492.28.127.25516,382
11592.28.128.0/1892.28.128.1 to 92.28.191.25492.28.191.25516,382
11692.28.192.0/1892.28.192.1 to 92.28.255.25492.28.255.25516,382
11792.29.0.0/1892.29.0.1 to 92.29.63.25492.29.63.25516,382
11892.29.64.0/1892.29.64.1 to 92.29.127.25492.29.127.25516,382
11992.29.128.0/1892.29.128.1 to 92.29.191.25492.29.191.25516,382
12092.29.192.0/1892.29.192.1 to 92.29.255.25492.29.255.25516,382
12192.30.0.0/1892.30.0.1 to 92.30.63.25492.30.63.25516,382
12292.30.64.0/1892.30.64.1 to 92.30.127.25492.30.127.25516,382
12392.30.128.0/1892.30.128.1 to 92.30.191.25492.30.191.25516,382
12492.30.192.0/1892.30.192.1 to 92.30.255.25492.30.255.25516,382
12592.31.0.0/1892.31.0.1 to 92.31.63.25492.31.63.25516,382
12692.31.64.0/1892.31.64.1 to 92.31.127.25492.31.127.25516,382
12792.31.128.0/1892.31.128.1 to 92.31.191.25492.31.191.25516,382
12892.31.192.0/1892.31.192.1 to 92.31.255.25492.31.255.25516,382
12992.32.0.0/1892.32.0.1 to 92.32.63.25492.32.63.25516,382
13092.32.64.0/1892.32.64.1 to 92.32.127.25492.32.127.25516,382
13192.32.128.0/1892.32.128.1 to 92.32.191.25492.32.191.25516,382
13292.32.192.0/1892.32.192.1 to 92.32.255.25492.32.255.25516,382
13392.33.0.0/1892.33.0.1 to 92.33.63.25492.33.63.25516,382
13492.33.64.0/1892.33.64.1 to 92.33.127.25492.33.127.25516,382
13592.33.128.0/1892.33.128.1 to 92.33.191.25492.33.191.25516,382
13692.33.192.0/1892.33.192.1 to 92.33.255.25492.33.255.25516,382
13792.34.0.0/1892.34.0.1 to 92.34.63.25492.34.63.25516,382
13892.34.64.0/1892.34.64.1 to 92.34.127.25492.34.127.25516,382
13992.34.128.0/1892.34.128.1 to 92.34.191.25492.34.191.25516,382
14092.34.192.0/1892.34.192.1 to 92.34.255.25492.34.255.25516,382
14192.35.0.0/1892.35.0.1 to 92.35.63.25492.35.63.25516,382
14292.35.64.0/1892.35.64.1 to 92.35.127.25492.35.127.25516,382
14392.35.128.0/1892.35.128.1 to 92.35.191.25492.35.191.25516,382
14492.35.192.0/1892.35.192.1 to 92.35.255.25492.35.255.25516,382
14592.36.0.0/1892.36.0.1 to 92.36.63.25492.36.63.25516,382
14692.36.64.0/1892.36.64.1 to 92.36.127.25492.36.127.25516,382
14792.36.128.0/1892.36.128.1 to 92.36.191.25492.36.191.25516,382
14892.36.192.0/1892.36.192.1 to 92.36.255.25492.36.255.25516,382
14992.37.0.0/1892.37.0.1 to 92.37.63.25492.37.63.25516,382
15092.37.64.0/1892.37.64.1 to 92.37.127.25492.37.127.25516,382
15192.37.128.0/1892.37.128.1 to 92.37.191.25492.37.191.25516,382
15292.37.192.0/1892.37.192.1 to 92.37.255.25492.37.255.25516,382
15392.38.0.0/1892.38.0.1 to 92.38.63.25492.38.63.25516,382
15492.38.64.0/1892.38.64.1 to 92.38.127.25492.38.127.25516,382
15592.38.128.0/1892.38.128.1 to 92.38.191.25492.38.191.25516,382
15692.38.192.0/1892.38.192.1 to 92.38.255.25492.38.255.25516,382
15792.39.0.0/1892.39.0.1 to 92.39.63.25492.39.63.25516,382
15892.39.64.0/1892.39.64.1 to 92.39.127.25492.39.127.25516,382
15992.39.128.0/1892.39.128.1 to 92.39.191.25492.39.191.25516,382
16092.39.192.0/1892.39.192.1 to 92.39.255.25492.39.255.25516,382
16192.40.0.0/1892.40.0.1 to 92.40.63.25492.40.63.25516,382
16292.40.64.0/1892.40.64.1 to 92.40.127.25492.40.127.25516,382
16392.40.128.0/1892.40.128.1 to 92.40.191.25492.40.191.25516,382
16492.40.192.0/1892.40.192.1 to 92.40.255.25492.40.255.25516,382
16592.41.0.0/1892.41.0.1 to 92.41.63.25492.41.63.25516,382
16692.41.64.0/1892.41.64.1 to 92.41.127.25492.41.127.25516,382
16792.41.128.0/1892.41.128.1 to 92.41.191.25492.41.191.25516,382
16892.41.192.0/1892.41.192.1 to 92.41.255.25492.41.255.25516,382
16992.42.0.0/1892.42.0.1 to 92.42.63.25492.42.63.25516,382
17092.42.64.0/1892.42.64.1 to 92.42.127.25492.42.127.25516,382
17192.42.128.0/1892.42.128.1 to 92.42.191.25492.42.191.25516,382
17292.42.192.0/1892.42.192.1 to 92.42.255.25492.42.255.25516,382
17392.43.0.0/1892.43.0.1 to 92.43.63.25492.43.63.25516,382
17492.43.64.0/1892.43.64.1 to 92.43.127.25492.43.127.25516,382
17592.43.128.0/1892.43.128.1 to 92.43.191.25492.43.191.25516,382
17692.43.192.0/1892.43.192.1 to 92.43.255.25492.43.255.25516,382
17792.44.0.0/1892.44.0.1 to 92.44.63.25492.44.63.25516,382
17892.44.64.0/1892.44.64.1 to 92.44.127.25492.44.127.25516,382
17992.44.128.0/1892.44.128.1 to 92.44.191.25492.44.191.25516,382
18092.44.192.0/1892.44.192.1 to 92.44.255.25492.44.255.25516,382
18192.45.0.0/1892.45.0.1 to 92.45.63.25492.45.63.25516,382
18292.45.64.0/1892.45.64.1 to 92.45.127.25492.45.127.25516,382
18392.45.128.0/1892.45.128.1 to 92.45.191.25492.45.191.25516,382
18492.45.192.0/1892.45.192.1 to 92.45.255.25492.45.255.25516,382
18592.46.0.0/1892.46.0.1 to 92.46.63.25492.46.63.25516,382
18692.46.64.0/1892.46.64.1 to 92.46.127.25492.46.127.25516,382
18792.46.128.0/1892.46.128.1 to 92.46.191.25492.46.191.25516,382
18892.46.192.0/1892.46.192.1 to 92.46.255.25492.46.255.25516,382
18992.47.0.0/1892.47.0.1 to 92.47.63.25492.47.63.25516,382
19092.47.64.0/1892.47.64.1 to 92.47.127.25492.47.127.25516,382
19192.47.128.0/1892.47.128.1 to 92.47.191.25492.47.191.25516,382
19292.47.192.0/1892.47.192.1 to 92.47.255.25492.47.255.25516,382
19392.48.0.0/1892.48.0.1 to 92.48.63.25492.48.63.25516,382
19492.48.64.0/1892.48.64.1 to 92.48.127.25492.48.127.25516,382
19592.48.128.0/1892.48.128.1 to 92.48.191.25492.48.191.25516,382
19692.48.192.0/1892.48.192.1 to 92.48.255.25492.48.255.25516,382
19792.49.0.0/1892.49.0.1 to 92.49.63.25492.49.63.25516,382
19892.49.64.0/1892.49.64.1 to 92.49.127.25492.49.127.25516,382
19992.49.128.0/1892.49.128.1 to 92.49.191.25492.49.191.25516,382
20092.49.192.0/1892.49.192.1 to 92.49.255.25492.49.255.25516,382
20192.50.0.0/1892.50.0.1 to 92.50.63.25492.50.63.25516,382
20292.50.64.0/1892.50.64.1 to 92.50.127.25492.50.127.25516,382
20392.50.128.0/1892.50.128.1 to 92.50.191.25492.50.191.25516,382
20492.50.192.0/1892.50.192.1 to 92.50.255.25492.50.255.25516,382
20592.51.0.0/1892.51.0.1 to 92.51.63.25492.51.63.25516,382
20692.51.64.0/1892.51.64.1 to 92.51.127.25492.51.127.25516,382
20792.51.128.0/1892.51.128.1 to 92.51.191.25492.51.191.25516,382
20892.51.192.0/1892.51.192.1 to 92.51.255.25492.51.255.25516,382
20992.52.0.0/1892.52.0.1 to 92.52.63.25492.52.63.25516,382
21092.52.64.0/1892.52.64.1 to 92.52.127.25492.52.127.25516,382
21192.52.128.0/1892.52.128.1 to 92.52.191.25492.52.191.25516,382
21292.52.192.0/1892.52.192.1 to 92.52.255.25492.52.255.25516,382
21392.53.0.0/1892.53.0.1 to 92.53.63.25492.53.63.25516,382
21492.53.64.0/1892.53.64.1 to 92.53.127.25492.53.127.25516,382
21592.53.128.0/1892.53.128.1 to 92.53.191.25492.53.191.25516,382
21692.53.192.0/1892.53.192.1 to 92.53.255.25492.53.255.25516,382
21792.54.0.0/1892.54.0.1 to 92.54.63.25492.54.63.25516,382
21892.54.64.0/1892.54.64.1 to 92.54.127.25492.54.127.25516,382
21992.54.128.0/1892.54.128.1 to 92.54.191.25492.54.191.25516,382
22092.54.192.0/1892.54.192.1 to 92.54.255.25492.54.255.25516,382
22192.55.0.0/1892.55.0.1 to 92.55.63.25492.55.63.25516,382
22292.55.64.0/1892.55.64.1 to 92.55.127.25492.55.127.25516,382
22392.55.128.0/1892.55.128.1 to 92.55.191.25492.55.191.25516,382
22492.55.192.0/1892.55.192.1 to 92.55.255.25492.55.255.25516,382
22592.56.0.0/1892.56.0.1 to 92.56.63.25492.56.63.25516,382
22692.56.64.0/1892.56.64.1 to 92.56.127.25492.56.127.25516,382
22792.56.128.0/1892.56.128.1 to 92.56.191.25492.56.191.25516,382
22892.56.192.0/1892.56.192.1 to 92.56.255.25492.56.255.25516,382
22992.57.0.0/1892.57.0.1 to 92.57.63.25492.57.63.25516,382
23092.57.64.0/1892.57.64.1 to 92.57.127.25492.57.127.25516,382
23192.57.128.0/1892.57.128.1 to 92.57.191.25492.57.191.25516,382
23292.57.192.0/1892.57.192.1 to 92.57.255.25492.57.255.25516,382
23392.58.0.0/1892.58.0.1 to 92.58.63.25492.58.63.25516,382
23492.58.64.0/1892.58.64.1 to 92.58.127.25492.58.127.25516,382
23592.58.128.0/1892.58.128.1 to 92.58.191.25492.58.191.25516,382
23692.58.192.0/1892.58.192.1 to 92.58.255.25492.58.255.25516,382
23792.59.0.0/1892.59.0.1 to 92.59.63.25492.59.63.25516,382
23892.59.64.0/1892.59.64.1 to 92.59.127.25492.59.127.25516,382
23992.59.128.0/1892.59.128.1 to 92.59.191.25492.59.191.25516,382
24092.59.192.0/1892.59.192.1 to 92.59.255.25492.59.255.25516,382
24192.60.0.0/1892.60.0.1 to 92.60.63.25492.60.63.25516,382
24292.60.64.0/1892.60.64.1 to 92.60.127.25492.60.127.25516,382
24392.60.128.0/1892.60.128.1 to 92.60.191.25492.60.191.25516,382
24492.60.192.0/1892.60.192.1 to 92.60.255.25492.60.255.25516,382
24592.61.0.0/1892.61.0.1 to 92.61.63.25492.61.63.25516,382
24692.61.64.0/1892.61.64.1 to 92.61.127.25492.61.127.25516,382
24792.61.128.0/1892.61.128.1 to 92.61.191.25492.61.191.25516,382
24892.61.192.0/1892.61.192.1 to 92.61.255.25492.61.255.25516,382
24992.62.0.0/1892.62.0.1 to 92.62.63.25492.62.63.25516,382
25092.62.64.0/1892.62.64.1 to 92.62.127.25492.62.127.25516,382
25192.62.128.0/1892.62.128.1 to 92.62.191.25492.62.191.25516,382
25292.62.192.0/1892.62.192.1 to 92.62.255.25492.62.255.25516,382
25392.63.0.0/1892.63.0.1 to 92.63.63.25492.63.63.25516,382
25492.63.64.0/1892.63.64.1 to 92.63.127.25492.63.127.25516,382
25592.63.128.0/1892.63.128.1 to 92.63.191.25492.63.191.25516,382
25692.63.192.0/1892.63.192.1 to 92.63.255.25492.63.255.25516,382

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.