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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.

Network3.200.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
3.200.0.0
Broadcast address
3.203.255.255
First usable
3.200.0.1
Last usable
3.203.255.254
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 03C80000 · Integer 63438848 to 63700991
Reverse DNS zones
200.3.in-addr.arpa
201.3.in-addr.arpa
202.3.in-addr.arpa
203.3.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
Address00000011.11001000.00000000.000000003.200.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00000011.11001000.00000000.000000003.200.0.0
Broadcast00000011.11001011.11111111.111111113.203.255.255
Split into smaller subnets/26
/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)

3.200.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
13.200.0.0/263.200.0.1 to 3.200.0.623.200.0.6362
23.200.0.64/263.200.0.65 to 3.200.0.1263.200.0.12762
33.200.0.128/263.200.0.129 to 3.200.0.1903.200.0.19162
43.200.0.192/263.200.0.193 to 3.200.0.2543.200.0.25562
53.200.1.0/263.200.1.1 to 3.200.1.623.200.1.6362
63.200.1.64/263.200.1.65 to 3.200.1.1263.200.1.12762
73.200.1.128/263.200.1.129 to 3.200.1.1903.200.1.19162
83.200.1.192/263.200.1.193 to 3.200.1.2543.200.1.25562
93.200.2.0/263.200.2.1 to 3.200.2.623.200.2.6362
103.200.2.64/263.200.2.65 to 3.200.2.1263.200.2.12762
113.200.2.128/263.200.2.129 to 3.200.2.1903.200.2.19162
123.200.2.192/263.200.2.193 to 3.200.2.2543.200.2.25562
133.200.3.0/263.200.3.1 to 3.200.3.623.200.3.6362
143.200.3.64/263.200.3.65 to 3.200.3.1263.200.3.12762
153.200.3.128/263.200.3.129 to 3.200.3.1903.200.3.19162
163.200.3.192/263.200.3.193 to 3.200.3.2543.200.3.25562
173.200.4.0/263.200.4.1 to 3.200.4.623.200.4.6362
183.200.4.64/263.200.4.65 to 3.200.4.1263.200.4.12762
193.200.4.128/263.200.4.129 to 3.200.4.1903.200.4.19162
203.200.4.192/263.200.4.193 to 3.200.4.2543.200.4.25562
213.200.5.0/263.200.5.1 to 3.200.5.623.200.5.6362
223.200.5.64/263.200.5.65 to 3.200.5.1263.200.5.12762
233.200.5.128/263.200.5.129 to 3.200.5.1903.200.5.19162
243.200.5.192/263.200.5.193 to 3.200.5.2543.200.5.25562
253.200.6.0/263.200.6.1 to 3.200.6.623.200.6.6362
263.200.6.64/263.200.6.65 to 3.200.6.1263.200.6.12762
273.200.6.128/263.200.6.129 to 3.200.6.1903.200.6.19162
283.200.6.192/263.200.6.193 to 3.200.6.2543.200.6.25562
293.200.7.0/263.200.7.1 to 3.200.7.623.200.7.6362
303.200.7.64/263.200.7.65 to 3.200.7.1263.200.7.12762
313.200.7.128/263.200.7.129 to 3.200.7.1903.200.7.19162
323.200.7.192/263.200.7.193 to 3.200.7.2543.200.7.25562
333.200.8.0/263.200.8.1 to 3.200.8.623.200.8.6362
343.200.8.64/263.200.8.65 to 3.200.8.1263.200.8.12762
353.200.8.128/263.200.8.129 to 3.200.8.1903.200.8.19162
363.200.8.192/263.200.8.193 to 3.200.8.2543.200.8.25562
373.200.9.0/263.200.9.1 to 3.200.9.623.200.9.6362
383.200.9.64/263.200.9.65 to 3.200.9.1263.200.9.12762
393.200.9.128/263.200.9.129 to 3.200.9.1903.200.9.19162
403.200.9.192/263.200.9.193 to 3.200.9.2543.200.9.25562
413.200.10.0/263.200.10.1 to 3.200.10.623.200.10.6362
423.200.10.64/263.200.10.65 to 3.200.10.1263.200.10.12762
433.200.10.128/263.200.10.129 to 3.200.10.1903.200.10.19162
443.200.10.192/263.200.10.193 to 3.200.10.2543.200.10.25562
453.200.11.0/263.200.11.1 to 3.200.11.623.200.11.6362
463.200.11.64/263.200.11.65 to 3.200.11.1263.200.11.12762
473.200.11.128/263.200.11.129 to 3.200.11.1903.200.11.19162
483.200.11.192/263.200.11.193 to 3.200.11.2543.200.11.25562
493.200.12.0/263.200.12.1 to 3.200.12.623.200.12.6362
503.200.12.64/263.200.12.65 to 3.200.12.1263.200.12.12762
513.200.12.128/263.200.12.129 to 3.200.12.1903.200.12.19162
523.200.12.192/263.200.12.193 to 3.200.12.2543.200.12.25562
533.200.13.0/263.200.13.1 to 3.200.13.623.200.13.6362
543.200.13.64/263.200.13.65 to 3.200.13.1263.200.13.12762
553.200.13.128/263.200.13.129 to 3.200.13.1903.200.13.19162
563.200.13.192/263.200.13.193 to 3.200.13.2543.200.13.25562
573.200.14.0/263.200.14.1 to 3.200.14.623.200.14.6362
583.200.14.64/263.200.14.65 to 3.200.14.1263.200.14.12762
593.200.14.128/263.200.14.129 to 3.200.14.1903.200.14.19162
603.200.14.192/263.200.14.193 to 3.200.14.2543.200.14.25562
613.200.15.0/263.200.15.1 to 3.200.15.623.200.15.6362
623.200.15.64/263.200.15.65 to 3.200.15.1263.200.15.12762
633.200.15.128/263.200.15.129 to 3.200.15.1903.200.15.19162
643.200.15.192/263.200.15.193 to 3.200.15.2543.200.15.25562
653.200.16.0/263.200.16.1 to 3.200.16.623.200.16.6362
663.200.16.64/263.200.16.65 to 3.200.16.1263.200.16.12762
673.200.16.128/263.200.16.129 to 3.200.16.1903.200.16.19162
683.200.16.192/263.200.16.193 to 3.200.16.2543.200.16.25562
693.200.17.0/263.200.17.1 to 3.200.17.623.200.17.6362
703.200.17.64/263.200.17.65 to 3.200.17.1263.200.17.12762
713.200.17.128/263.200.17.129 to 3.200.17.1903.200.17.19162
723.200.17.192/263.200.17.193 to 3.200.17.2543.200.17.25562
733.200.18.0/263.200.18.1 to 3.200.18.623.200.18.6362
743.200.18.64/263.200.18.65 to 3.200.18.1263.200.18.12762
753.200.18.128/263.200.18.129 to 3.200.18.1903.200.18.19162
763.200.18.192/263.200.18.193 to 3.200.18.2543.200.18.25562
773.200.19.0/263.200.19.1 to 3.200.19.623.200.19.6362
783.200.19.64/263.200.19.65 to 3.200.19.1263.200.19.12762
793.200.19.128/263.200.19.129 to 3.200.19.1903.200.19.19162
803.200.19.192/263.200.19.193 to 3.200.19.2543.200.19.25562
813.200.20.0/263.200.20.1 to 3.200.20.623.200.20.6362
823.200.20.64/263.200.20.65 to 3.200.20.1263.200.20.12762
833.200.20.128/263.200.20.129 to 3.200.20.1903.200.20.19162
843.200.20.192/263.200.20.193 to 3.200.20.2543.200.20.25562
853.200.21.0/263.200.21.1 to 3.200.21.623.200.21.6362
863.200.21.64/263.200.21.65 to 3.200.21.1263.200.21.12762
873.200.21.128/263.200.21.129 to 3.200.21.1903.200.21.19162
883.200.21.192/263.200.21.193 to 3.200.21.2543.200.21.25562
893.200.22.0/263.200.22.1 to 3.200.22.623.200.22.6362
903.200.22.64/263.200.22.65 to 3.200.22.1263.200.22.12762
913.200.22.128/263.200.22.129 to 3.200.22.1903.200.22.19162
923.200.22.192/263.200.22.193 to 3.200.22.2543.200.22.25562
933.200.23.0/263.200.23.1 to 3.200.23.623.200.23.6362
943.200.23.64/263.200.23.65 to 3.200.23.1263.200.23.12762
953.200.23.128/263.200.23.129 to 3.200.23.1903.200.23.19162
963.200.23.192/263.200.23.193 to 3.200.23.2543.200.23.25562
973.200.24.0/263.200.24.1 to 3.200.24.623.200.24.6362
983.200.24.64/263.200.24.65 to 3.200.24.1263.200.24.12762
993.200.24.128/263.200.24.129 to 3.200.24.1903.200.24.19162
1003.200.24.192/263.200.24.193 to 3.200.24.2543.200.24.25562
1013.200.25.0/263.200.25.1 to 3.200.25.623.200.25.6362
1023.200.25.64/263.200.25.65 to 3.200.25.1263.200.25.12762
1033.200.25.128/263.200.25.129 to 3.200.25.1903.200.25.19162
1043.200.25.192/263.200.25.193 to 3.200.25.2543.200.25.25562
1053.200.26.0/263.200.26.1 to 3.200.26.623.200.26.6362
1063.200.26.64/263.200.26.65 to 3.200.26.1263.200.26.12762
1073.200.26.128/263.200.26.129 to 3.200.26.1903.200.26.19162
1083.200.26.192/263.200.26.193 to 3.200.26.2543.200.26.25562
1093.200.27.0/263.200.27.1 to 3.200.27.623.200.27.6362
1103.200.27.64/263.200.27.65 to 3.200.27.1263.200.27.12762
1113.200.27.128/263.200.27.129 to 3.200.27.1903.200.27.19162
1123.200.27.192/263.200.27.193 to 3.200.27.2543.200.27.25562
1133.200.28.0/263.200.28.1 to 3.200.28.623.200.28.6362
1143.200.28.64/263.200.28.65 to 3.200.28.1263.200.28.12762
1153.200.28.128/263.200.28.129 to 3.200.28.1903.200.28.19162
1163.200.28.192/263.200.28.193 to 3.200.28.2543.200.28.25562
1173.200.29.0/263.200.29.1 to 3.200.29.623.200.29.6362
1183.200.29.64/263.200.29.65 to 3.200.29.1263.200.29.12762
1193.200.29.128/263.200.29.129 to 3.200.29.1903.200.29.19162
1203.200.29.192/263.200.29.193 to 3.200.29.2543.200.29.25562
1213.200.30.0/263.200.30.1 to 3.200.30.623.200.30.6362
1223.200.30.64/263.200.30.65 to 3.200.30.1263.200.30.12762
1233.200.30.128/263.200.30.129 to 3.200.30.1903.200.30.19162
1243.200.30.192/263.200.30.193 to 3.200.30.2543.200.30.25562
1253.200.31.0/263.200.31.1 to 3.200.31.623.200.31.6362
1263.200.31.64/263.200.31.65 to 3.200.31.1263.200.31.12762
1273.200.31.128/263.200.31.129 to 3.200.31.1903.200.31.19162
1283.200.31.192/263.200.31.193 to 3.200.31.2543.200.31.25562
1293.200.32.0/263.200.32.1 to 3.200.32.623.200.32.6362
1303.200.32.64/263.200.32.65 to 3.200.32.1263.200.32.12762
1313.200.32.128/263.200.32.129 to 3.200.32.1903.200.32.19162
1323.200.32.192/263.200.32.193 to 3.200.32.2543.200.32.25562
1333.200.33.0/263.200.33.1 to 3.200.33.623.200.33.6362
1343.200.33.64/263.200.33.65 to 3.200.33.1263.200.33.12762
1353.200.33.128/263.200.33.129 to 3.200.33.1903.200.33.19162
1363.200.33.192/263.200.33.193 to 3.200.33.2543.200.33.25562
1373.200.34.0/263.200.34.1 to 3.200.34.623.200.34.6362
1383.200.34.64/263.200.34.65 to 3.200.34.1263.200.34.12762
1393.200.34.128/263.200.34.129 to 3.200.34.1903.200.34.19162
1403.200.34.192/263.200.34.193 to 3.200.34.2543.200.34.25562
1413.200.35.0/263.200.35.1 to 3.200.35.623.200.35.6362
1423.200.35.64/263.200.35.65 to 3.200.35.1263.200.35.12762
1433.200.35.128/263.200.35.129 to 3.200.35.1903.200.35.19162
1443.200.35.192/263.200.35.193 to 3.200.35.2543.200.35.25562
1453.200.36.0/263.200.36.1 to 3.200.36.623.200.36.6362
1463.200.36.64/263.200.36.65 to 3.200.36.1263.200.36.12762
1473.200.36.128/263.200.36.129 to 3.200.36.1903.200.36.19162
1483.200.36.192/263.200.36.193 to 3.200.36.2543.200.36.25562
1493.200.37.0/263.200.37.1 to 3.200.37.623.200.37.6362
1503.200.37.64/263.200.37.65 to 3.200.37.1263.200.37.12762
1513.200.37.128/263.200.37.129 to 3.200.37.1903.200.37.19162
1523.200.37.192/263.200.37.193 to 3.200.37.2543.200.37.25562
1533.200.38.0/263.200.38.1 to 3.200.38.623.200.38.6362
1543.200.38.64/263.200.38.65 to 3.200.38.1263.200.38.12762
1553.200.38.128/263.200.38.129 to 3.200.38.1903.200.38.19162
1563.200.38.192/263.200.38.193 to 3.200.38.2543.200.38.25562
1573.200.39.0/263.200.39.1 to 3.200.39.623.200.39.6362
1583.200.39.64/263.200.39.65 to 3.200.39.1263.200.39.12762
1593.200.39.128/263.200.39.129 to 3.200.39.1903.200.39.19162
1603.200.39.192/263.200.39.193 to 3.200.39.2543.200.39.25562
1613.200.40.0/263.200.40.1 to 3.200.40.623.200.40.6362
1623.200.40.64/263.200.40.65 to 3.200.40.1263.200.40.12762
1633.200.40.128/263.200.40.129 to 3.200.40.1903.200.40.19162
1643.200.40.192/263.200.40.193 to 3.200.40.2543.200.40.25562
1653.200.41.0/263.200.41.1 to 3.200.41.623.200.41.6362
1663.200.41.64/263.200.41.65 to 3.200.41.1263.200.41.12762
1673.200.41.128/263.200.41.129 to 3.200.41.1903.200.41.19162
1683.200.41.192/263.200.41.193 to 3.200.41.2543.200.41.25562
1693.200.42.0/263.200.42.1 to 3.200.42.623.200.42.6362
1703.200.42.64/263.200.42.65 to 3.200.42.1263.200.42.12762
1713.200.42.128/263.200.42.129 to 3.200.42.1903.200.42.19162
1723.200.42.192/263.200.42.193 to 3.200.42.2543.200.42.25562
1733.200.43.0/263.200.43.1 to 3.200.43.623.200.43.6362
1743.200.43.64/263.200.43.65 to 3.200.43.1263.200.43.12762
1753.200.43.128/263.200.43.129 to 3.200.43.1903.200.43.19162
1763.200.43.192/263.200.43.193 to 3.200.43.2543.200.43.25562
1773.200.44.0/263.200.44.1 to 3.200.44.623.200.44.6362
1783.200.44.64/263.200.44.65 to 3.200.44.1263.200.44.12762
1793.200.44.128/263.200.44.129 to 3.200.44.1903.200.44.19162
1803.200.44.192/263.200.44.193 to 3.200.44.2543.200.44.25562
1813.200.45.0/263.200.45.1 to 3.200.45.623.200.45.6362
1823.200.45.64/263.200.45.65 to 3.200.45.1263.200.45.12762
1833.200.45.128/263.200.45.129 to 3.200.45.1903.200.45.19162
1843.200.45.192/263.200.45.193 to 3.200.45.2543.200.45.25562
1853.200.46.0/263.200.46.1 to 3.200.46.623.200.46.6362
1863.200.46.64/263.200.46.65 to 3.200.46.1263.200.46.12762
1873.200.46.128/263.200.46.129 to 3.200.46.1903.200.46.19162
1883.200.46.192/263.200.46.193 to 3.200.46.2543.200.46.25562
1893.200.47.0/263.200.47.1 to 3.200.47.623.200.47.6362
1903.200.47.64/263.200.47.65 to 3.200.47.1263.200.47.12762
1913.200.47.128/263.200.47.129 to 3.200.47.1903.200.47.19162
1923.200.47.192/263.200.47.193 to 3.200.47.2543.200.47.25562
1933.200.48.0/263.200.48.1 to 3.200.48.623.200.48.6362
1943.200.48.64/263.200.48.65 to 3.200.48.1263.200.48.12762
1953.200.48.128/263.200.48.129 to 3.200.48.1903.200.48.19162
1963.200.48.192/263.200.48.193 to 3.200.48.2543.200.48.25562
1973.200.49.0/263.200.49.1 to 3.200.49.623.200.49.6362
1983.200.49.64/263.200.49.65 to 3.200.49.1263.200.49.12762
1993.200.49.128/263.200.49.129 to 3.200.49.1903.200.49.19162
2003.200.49.192/263.200.49.193 to 3.200.49.2543.200.49.25562
2013.200.50.0/263.200.50.1 to 3.200.50.623.200.50.6362
2023.200.50.64/263.200.50.65 to 3.200.50.1263.200.50.12762
2033.200.50.128/263.200.50.129 to 3.200.50.1903.200.50.19162
2043.200.50.192/263.200.50.193 to 3.200.50.2543.200.50.25562
2053.200.51.0/263.200.51.1 to 3.200.51.623.200.51.6362
2063.200.51.64/263.200.51.65 to 3.200.51.1263.200.51.12762
2073.200.51.128/263.200.51.129 to 3.200.51.1903.200.51.19162
2083.200.51.192/263.200.51.193 to 3.200.51.2543.200.51.25562
2093.200.52.0/263.200.52.1 to 3.200.52.623.200.52.6362
2103.200.52.64/263.200.52.65 to 3.200.52.1263.200.52.12762
2113.200.52.128/263.200.52.129 to 3.200.52.1903.200.52.19162
2123.200.52.192/263.200.52.193 to 3.200.52.2543.200.52.25562
2133.200.53.0/263.200.53.1 to 3.200.53.623.200.53.6362
2143.200.53.64/263.200.53.65 to 3.200.53.1263.200.53.12762
2153.200.53.128/263.200.53.129 to 3.200.53.1903.200.53.19162
2163.200.53.192/263.200.53.193 to 3.200.53.2543.200.53.25562
2173.200.54.0/263.200.54.1 to 3.200.54.623.200.54.6362
2183.200.54.64/263.200.54.65 to 3.200.54.1263.200.54.12762
2193.200.54.128/263.200.54.129 to 3.200.54.1903.200.54.19162
2203.200.54.192/263.200.54.193 to 3.200.54.2543.200.54.25562
2213.200.55.0/263.200.55.1 to 3.200.55.623.200.55.6362
2223.200.55.64/263.200.55.65 to 3.200.55.1263.200.55.12762
2233.200.55.128/263.200.55.129 to 3.200.55.1903.200.55.19162
2243.200.55.192/263.200.55.193 to 3.200.55.2543.200.55.25562
2253.200.56.0/263.200.56.1 to 3.200.56.623.200.56.6362
2263.200.56.64/263.200.56.65 to 3.200.56.1263.200.56.12762
2273.200.56.128/263.200.56.129 to 3.200.56.1903.200.56.19162
2283.200.56.192/263.200.56.193 to 3.200.56.2543.200.56.25562
2293.200.57.0/263.200.57.1 to 3.200.57.623.200.57.6362
2303.200.57.64/263.200.57.65 to 3.200.57.1263.200.57.12762
2313.200.57.128/263.200.57.129 to 3.200.57.1903.200.57.19162
2323.200.57.192/263.200.57.193 to 3.200.57.2543.200.57.25562
2333.200.58.0/263.200.58.1 to 3.200.58.623.200.58.6362
2343.200.58.64/263.200.58.65 to 3.200.58.1263.200.58.12762
2353.200.58.128/263.200.58.129 to 3.200.58.1903.200.58.19162
2363.200.58.192/263.200.58.193 to 3.200.58.2543.200.58.25562
2373.200.59.0/263.200.59.1 to 3.200.59.623.200.59.6362
2383.200.59.64/263.200.59.65 to 3.200.59.1263.200.59.12762
2393.200.59.128/263.200.59.129 to 3.200.59.1903.200.59.19162
2403.200.59.192/263.200.59.193 to 3.200.59.2543.200.59.25562
2413.200.60.0/263.200.60.1 to 3.200.60.623.200.60.6362
2423.200.60.64/263.200.60.65 to 3.200.60.1263.200.60.12762
2433.200.60.128/263.200.60.129 to 3.200.60.1903.200.60.19162
2443.200.60.192/263.200.60.193 to 3.200.60.2543.200.60.25562
2453.200.61.0/263.200.61.1 to 3.200.61.623.200.61.6362
2463.200.61.64/263.200.61.65 to 3.200.61.1263.200.61.12762
2473.200.61.128/263.200.61.129 to 3.200.61.1903.200.61.19162
2483.200.61.192/263.200.61.193 to 3.200.61.2543.200.61.25562
2493.200.62.0/263.200.62.1 to 3.200.62.623.200.62.6362
2503.200.62.64/263.200.62.65 to 3.200.62.1263.200.62.12762
2513.200.62.128/263.200.62.129 to 3.200.62.1903.200.62.19162
2523.200.62.192/263.200.62.193 to 3.200.62.2543.200.62.25562
2533.200.63.0/263.200.63.1 to 3.200.63.623.200.63.6362
2543.200.63.64/263.200.63.65 to 3.200.63.1263.200.63.12762
2553.200.63.128/263.200.63.129 to 3.200.63.1903.200.63.19162
2563.200.63.192/263.200.63.193 to 3.200.63.2543.200.63.25562

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.