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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.

Network3.160.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
3.160.0.0
Broadcast address
3.167.255.255
First usable
3.160.0.1
Last usable
3.167.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 03A00000 · Integer 60817408 to 61341695
Reverse DNS zones
160.3.in-addr.arpa
161.3.in-addr.arpa
162.3.in-addr.arpa
163.3.in-addr.arpa
164.3.in-addr.arpa
165.3.in-addr.arpa
166.3.in-addr.arpa
167.3.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00000011.10100000.00000000.000000003.160.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network00000011.10100000.00000000.000000003.160.0.0
Broadcast00000011.10100111.11111111.111111113.167.255.255
Split into smaller subnets/25
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

3.160.0.0/13 makes 4,096 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
13.160.0.0/253.160.0.1 to 3.160.0.1263.160.0.127126
23.160.0.128/253.160.0.129 to 3.160.0.2543.160.0.255126
33.160.1.0/253.160.1.1 to 3.160.1.1263.160.1.127126
43.160.1.128/253.160.1.129 to 3.160.1.2543.160.1.255126
53.160.2.0/253.160.2.1 to 3.160.2.1263.160.2.127126
63.160.2.128/253.160.2.129 to 3.160.2.2543.160.2.255126
73.160.3.0/253.160.3.1 to 3.160.3.1263.160.3.127126
83.160.3.128/253.160.3.129 to 3.160.3.2543.160.3.255126
93.160.4.0/253.160.4.1 to 3.160.4.1263.160.4.127126
103.160.4.128/253.160.4.129 to 3.160.4.2543.160.4.255126
113.160.5.0/253.160.5.1 to 3.160.5.1263.160.5.127126
123.160.5.128/253.160.5.129 to 3.160.5.2543.160.5.255126
133.160.6.0/253.160.6.1 to 3.160.6.1263.160.6.127126
143.160.6.128/253.160.6.129 to 3.160.6.2543.160.6.255126
153.160.7.0/253.160.7.1 to 3.160.7.1263.160.7.127126
163.160.7.128/253.160.7.129 to 3.160.7.2543.160.7.255126
173.160.8.0/253.160.8.1 to 3.160.8.1263.160.8.127126
183.160.8.128/253.160.8.129 to 3.160.8.2543.160.8.255126
193.160.9.0/253.160.9.1 to 3.160.9.1263.160.9.127126
203.160.9.128/253.160.9.129 to 3.160.9.2543.160.9.255126
213.160.10.0/253.160.10.1 to 3.160.10.1263.160.10.127126
223.160.10.128/253.160.10.129 to 3.160.10.2543.160.10.255126
233.160.11.0/253.160.11.1 to 3.160.11.1263.160.11.127126
243.160.11.128/253.160.11.129 to 3.160.11.2543.160.11.255126
253.160.12.0/253.160.12.1 to 3.160.12.1263.160.12.127126
263.160.12.128/253.160.12.129 to 3.160.12.2543.160.12.255126
273.160.13.0/253.160.13.1 to 3.160.13.1263.160.13.127126
283.160.13.128/253.160.13.129 to 3.160.13.2543.160.13.255126
293.160.14.0/253.160.14.1 to 3.160.14.1263.160.14.127126
303.160.14.128/253.160.14.129 to 3.160.14.2543.160.14.255126
313.160.15.0/253.160.15.1 to 3.160.15.1263.160.15.127126
323.160.15.128/253.160.15.129 to 3.160.15.2543.160.15.255126
333.160.16.0/253.160.16.1 to 3.160.16.1263.160.16.127126
343.160.16.128/253.160.16.129 to 3.160.16.2543.160.16.255126
353.160.17.0/253.160.17.1 to 3.160.17.1263.160.17.127126
363.160.17.128/253.160.17.129 to 3.160.17.2543.160.17.255126
373.160.18.0/253.160.18.1 to 3.160.18.1263.160.18.127126
383.160.18.128/253.160.18.129 to 3.160.18.2543.160.18.255126
393.160.19.0/253.160.19.1 to 3.160.19.1263.160.19.127126
403.160.19.128/253.160.19.129 to 3.160.19.2543.160.19.255126
413.160.20.0/253.160.20.1 to 3.160.20.1263.160.20.127126
423.160.20.128/253.160.20.129 to 3.160.20.2543.160.20.255126
433.160.21.0/253.160.21.1 to 3.160.21.1263.160.21.127126
443.160.21.128/253.160.21.129 to 3.160.21.2543.160.21.255126
453.160.22.0/253.160.22.1 to 3.160.22.1263.160.22.127126
463.160.22.128/253.160.22.129 to 3.160.22.2543.160.22.255126
473.160.23.0/253.160.23.1 to 3.160.23.1263.160.23.127126
483.160.23.128/253.160.23.129 to 3.160.23.2543.160.23.255126
493.160.24.0/253.160.24.1 to 3.160.24.1263.160.24.127126
503.160.24.128/253.160.24.129 to 3.160.24.2543.160.24.255126
513.160.25.0/253.160.25.1 to 3.160.25.1263.160.25.127126
523.160.25.128/253.160.25.129 to 3.160.25.2543.160.25.255126
533.160.26.0/253.160.26.1 to 3.160.26.1263.160.26.127126
543.160.26.128/253.160.26.129 to 3.160.26.2543.160.26.255126
553.160.27.0/253.160.27.1 to 3.160.27.1263.160.27.127126
563.160.27.128/253.160.27.129 to 3.160.27.2543.160.27.255126
573.160.28.0/253.160.28.1 to 3.160.28.1263.160.28.127126
583.160.28.128/253.160.28.129 to 3.160.28.2543.160.28.255126
593.160.29.0/253.160.29.1 to 3.160.29.1263.160.29.127126
603.160.29.128/253.160.29.129 to 3.160.29.2543.160.29.255126
613.160.30.0/253.160.30.1 to 3.160.30.1263.160.30.127126
623.160.30.128/253.160.30.129 to 3.160.30.2543.160.30.255126
633.160.31.0/253.160.31.1 to 3.160.31.1263.160.31.127126
643.160.31.128/253.160.31.129 to 3.160.31.2543.160.31.255126
653.160.32.0/253.160.32.1 to 3.160.32.1263.160.32.127126
663.160.32.128/253.160.32.129 to 3.160.32.2543.160.32.255126
673.160.33.0/253.160.33.1 to 3.160.33.1263.160.33.127126
683.160.33.128/253.160.33.129 to 3.160.33.2543.160.33.255126
693.160.34.0/253.160.34.1 to 3.160.34.1263.160.34.127126
703.160.34.128/253.160.34.129 to 3.160.34.2543.160.34.255126
713.160.35.0/253.160.35.1 to 3.160.35.1263.160.35.127126
723.160.35.128/253.160.35.129 to 3.160.35.2543.160.35.255126
733.160.36.0/253.160.36.1 to 3.160.36.1263.160.36.127126
743.160.36.128/253.160.36.129 to 3.160.36.2543.160.36.255126
753.160.37.0/253.160.37.1 to 3.160.37.1263.160.37.127126
763.160.37.128/253.160.37.129 to 3.160.37.2543.160.37.255126
773.160.38.0/253.160.38.1 to 3.160.38.1263.160.38.127126
783.160.38.128/253.160.38.129 to 3.160.38.2543.160.38.255126
793.160.39.0/253.160.39.1 to 3.160.39.1263.160.39.127126
803.160.39.128/253.160.39.129 to 3.160.39.2543.160.39.255126
813.160.40.0/253.160.40.1 to 3.160.40.1263.160.40.127126
823.160.40.128/253.160.40.129 to 3.160.40.2543.160.40.255126
833.160.41.0/253.160.41.1 to 3.160.41.1263.160.41.127126
843.160.41.128/253.160.41.129 to 3.160.41.2543.160.41.255126
853.160.42.0/253.160.42.1 to 3.160.42.1263.160.42.127126
863.160.42.128/253.160.42.129 to 3.160.42.2543.160.42.255126
873.160.43.0/253.160.43.1 to 3.160.43.1263.160.43.127126
883.160.43.128/253.160.43.129 to 3.160.43.2543.160.43.255126
893.160.44.0/253.160.44.1 to 3.160.44.1263.160.44.127126
903.160.44.128/253.160.44.129 to 3.160.44.2543.160.44.255126
913.160.45.0/253.160.45.1 to 3.160.45.1263.160.45.127126
923.160.45.128/253.160.45.129 to 3.160.45.2543.160.45.255126
933.160.46.0/253.160.46.1 to 3.160.46.1263.160.46.127126
943.160.46.128/253.160.46.129 to 3.160.46.2543.160.46.255126
953.160.47.0/253.160.47.1 to 3.160.47.1263.160.47.127126
963.160.47.128/253.160.47.129 to 3.160.47.2543.160.47.255126
973.160.48.0/253.160.48.1 to 3.160.48.1263.160.48.127126
983.160.48.128/253.160.48.129 to 3.160.48.2543.160.48.255126
993.160.49.0/253.160.49.1 to 3.160.49.1263.160.49.127126
1003.160.49.128/253.160.49.129 to 3.160.49.2543.160.49.255126
1013.160.50.0/253.160.50.1 to 3.160.50.1263.160.50.127126
1023.160.50.128/253.160.50.129 to 3.160.50.2543.160.50.255126
1033.160.51.0/253.160.51.1 to 3.160.51.1263.160.51.127126
1043.160.51.128/253.160.51.129 to 3.160.51.2543.160.51.255126
1053.160.52.0/253.160.52.1 to 3.160.52.1263.160.52.127126
1063.160.52.128/253.160.52.129 to 3.160.52.2543.160.52.255126
1073.160.53.0/253.160.53.1 to 3.160.53.1263.160.53.127126
1083.160.53.128/253.160.53.129 to 3.160.53.2543.160.53.255126
1093.160.54.0/253.160.54.1 to 3.160.54.1263.160.54.127126
1103.160.54.128/253.160.54.129 to 3.160.54.2543.160.54.255126
1113.160.55.0/253.160.55.1 to 3.160.55.1263.160.55.127126
1123.160.55.128/253.160.55.129 to 3.160.55.2543.160.55.255126
1133.160.56.0/253.160.56.1 to 3.160.56.1263.160.56.127126
1143.160.56.128/253.160.56.129 to 3.160.56.2543.160.56.255126
1153.160.57.0/253.160.57.1 to 3.160.57.1263.160.57.127126
1163.160.57.128/253.160.57.129 to 3.160.57.2543.160.57.255126
1173.160.58.0/253.160.58.1 to 3.160.58.1263.160.58.127126
1183.160.58.128/253.160.58.129 to 3.160.58.2543.160.58.255126
1193.160.59.0/253.160.59.1 to 3.160.59.1263.160.59.127126
1203.160.59.128/253.160.59.129 to 3.160.59.2543.160.59.255126
1213.160.60.0/253.160.60.1 to 3.160.60.1263.160.60.127126
1223.160.60.128/253.160.60.129 to 3.160.60.2543.160.60.255126
1233.160.61.0/253.160.61.1 to 3.160.61.1263.160.61.127126
1243.160.61.128/253.160.61.129 to 3.160.61.2543.160.61.255126
1253.160.62.0/253.160.62.1 to 3.160.62.1263.160.62.127126
1263.160.62.128/253.160.62.129 to 3.160.62.2543.160.62.255126
1273.160.63.0/253.160.63.1 to 3.160.63.1263.160.63.127126
1283.160.63.128/253.160.63.129 to 3.160.63.2543.160.63.255126
1293.160.64.0/253.160.64.1 to 3.160.64.1263.160.64.127126
1303.160.64.128/253.160.64.129 to 3.160.64.2543.160.64.255126
1313.160.65.0/253.160.65.1 to 3.160.65.1263.160.65.127126
1323.160.65.128/253.160.65.129 to 3.160.65.2543.160.65.255126
1333.160.66.0/253.160.66.1 to 3.160.66.1263.160.66.127126
1343.160.66.128/253.160.66.129 to 3.160.66.2543.160.66.255126
1353.160.67.0/253.160.67.1 to 3.160.67.1263.160.67.127126
1363.160.67.128/253.160.67.129 to 3.160.67.2543.160.67.255126
1373.160.68.0/253.160.68.1 to 3.160.68.1263.160.68.127126
1383.160.68.128/253.160.68.129 to 3.160.68.2543.160.68.255126
1393.160.69.0/253.160.69.1 to 3.160.69.1263.160.69.127126
1403.160.69.128/253.160.69.129 to 3.160.69.2543.160.69.255126
1413.160.70.0/253.160.70.1 to 3.160.70.1263.160.70.127126
1423.160.70.128/253.160.70.129 to 3.160.70.2543.160.70.255126
1433.160.71.0/253.160.71.1 to 3.160.71.1263.160.71.127126
1443.160.71.128/253.160.71.129 to 3.160.71.2543.160.71.255126
1453.160.72.0/253.160.72.1 to 3.160.72.1263.160.72.127126
1463.160.72.128/253.160.72.129 to 3.160.72.2543.160.72.255126
1473.160.73.0/253.160.73.1 to 3.160.73.1263.160.73.127126
1483.160.73.128/253.160.73.129 to 3.160.73.2543.160.73.255126
1493.160.74.0/253.160.74.1 to 3.160.74.1263.160.74.127126
1503.160.74.128/253.160.74.129 to 3.160.74.2543.160.74.255126
1513.160.75.0/253.160.75.1 to 3.160.75.1263.160.75.127126
1523.160.75.128/253.160.75.129 to 3.160.75.2543.160.75.255126
1533.160.76.0/253.160.76.1 to 3.160.76.1263.160.76.127126
1543.160.76.128/253.160.76.129 to 3.160.76.2543.160.76.255126
1553.160.77.0/253.160.77.1 to 3.160.77.1263.160.77.127126
1563.160.77.128/253.160.77.129 to 3.160.77.2543.160.77.255126
1573.160.78.0/253.160.78.1 to 3.160.78.1263.160.78.127126
1583.160.78.128/253.160.78.129 to 3.160.78.2543.160.78.255126
1593.160.79.0/253.160.79.1 to 3.160.79.1263.160.79.127126
1603.160.79.128/253.160.79.129 to 3.160.79.2543.160.79.255126
1613.160.80.0/253.160.80.1 to 3.160.80.1263.160.80.127126
1623.160.80.128/253.160.80.129 to 3.160.80.2543.160.80.255126
1633.160.81.0/253.160.81.1 to 3.160.81.1263.160.81.127126
1643.160.81.128/253.160.81.129 to 3.160.81.2543.160.81.255126
1653.160.82.0/253.160.82.1 to 3.160.82.1263.160.82.127126
1663.160.82.128/253.160.82.129 to 3.160.82.2543.160.82.255126
1673.160.83.0/253.160.83.1 to 3.160.83.1263.160.83.127126
1683.160.83.128/253.160.83.129 to 3.160.83.2543.160.83.255126
1693.160.84.0/253.160.84.1 to 3.160.84.1263.160.84.127126
1703.160.84.128/253.160.84.129 to 3.160.84.2543.160.84.255126
1713.160.85.0/253.160.85.1 to 3.160.85.1263.160.85.127126
1723.160.85.128/253.160.85.129 to 3.160.85.2543.160.85.255126
1733.160.86.0/253.160.86.1 to 3.160.86.1263.160.86.127126
1743.160.86.128/253.160.86.129 to 3.160.86.2543.160.86.255126
1753.160.87.0/253.160.87.1 to 3.160.87.1263.160.87.127126
1763.160.87.128/253.160.87.129 to 3.160.87.2543.160.87.255126
1773.160.88.0/253.160.88.1 to 3.160.88.1263.160.88.127126
1783.160.88.128/253.160.88.129 to 3.160.88.2543.160.88.255126
1793.160.89.0/253.160.89.1 to 3.160.89.1263.160.89.127126
1803.160.89.128/253.160.89.129 to 3.160.89.2543.160.89.255126
1813.160.90.0/253.160.90.1 to 3.160.90.1263.160.90.127126
1823.160.90.128/253.160.90.129 to 3.160.90.2543.160.90.255126
1833.160.91.0/253.160.91.1 to 3.160.91.1263.160.91.127126
1843.160.91.128/253.160.91.129 to 3.160.91.2543.160.91.255126
1853.160.92.0/253.160.92.1 to 3.160.92.1263.160.92.127126
1863.160.92.128/253.160.92.129 to 3.160.92.2543.160.92.255126
1873.160.93.0/253.160.93.1 to 3.160.93.1263.160.93.127126
1883.160.93.128/253.160.93.129 to 3.160.93.2543.160.93.255126
1893.160.94.0/253.160.94.1 to 3.160.94.1263.160.94.127126
1903.160.94.128/253.160.94.129 to 3.160.94.2543.160.94.255126
1913.160.95.0/253.160.95.1 to 3.160.95.1263.160.95.127126
1923.160.95.128/253.160.95.129 to 3.160.95.2543.160.95.255126
1933.160.96.0/253.160.96.1 to 3.160.96.1263.160.96.127126
1943.160.96.128/253.160.96.129 to 3.160.96.2543.160.96.255126
1953.160.97.0/253.160.97.1 to 3.160.97.1263.160.97.127126
1963.160.97.128/253.160.97.129 to 3.160.97.2543.160.97.255126
1973.160.98.0/253.160.98.1 to 3.160.98.1263.160.98.127126
1983.160.98.128/253.160.98.129 to 3.160.98.2543.160.98.255126
1993.160.99.0/253.160.99.1 to 3.160.99.1263.160.99.127126
2003.160.99.128/253.160.99.129 to 3.160.99.2543.160.99.255126
2013.160.100.0/253.160.100.1 to 3.160.100.1263.160.100.127126
2023.160.100.128/253.160.100.129 to 3.160.100.2543.160.100.255126
2033.160.101.0/253.160.101.1 to 3.160.101.1263.160.101.127126
2043.160.101.128/253.160.101.129 to 3.160.101.2543.160.101.255126
2053.160.102.0/253.160.102.1 to 3.160.102.1263.160.102.127126
2063.160.102.128/253.160.102.129 to 3.160.102.2543.160.102.255126
2073.160.103.0/253.160.103.1 to 3.160.103.1263.160.103.127126
2083.160.103.128/253.160.103.129 to 3.160.103.2543.160.103.255126
2093.160.104.0/253.160.104.1 to 3.160.104.1263.160.104.127126
2103.160.104.128/253.160.104.129 to 3.160.104.2543.160.104.255126
2113.160.105.0/253.160.105.1 to 3.160.105.1263.160.105.127126
2123.160.105.128/253.160.105.129 to 3.160.105.2543.160.105.255126
2133.160.106.0/253.160.106.1 to 3.160.106.1263.160.106.127126
2143.160.106.128/253.160.106.129 to 3.160.106.2543.160.106.255126
2153.160.107.0/253.160.107.1 to 3.160.107.1263.160.107.127126
2163.160.107.128/253.160.107.129 to 3.160.107.2543.160.107.255126
2173.160.108.0/253.160.108.1 to 3.160.108.1263.160.108.127126
2183.160.108.128/253.160.108.129 to 3.160.108.2543.160.108.255126
2193.160.109.0/253.160.109.1 to 3.160.109.1263.160.109.127126
2203.160.109.128/253.160.109.129 to 3.160.109.2543.160.109.255126
2213.160.110.0/253.160.110.1 to 3.160.110.1263.160.110.127126
2223.160.110.128/253.160.110.129 to 3.160.110.2543.160.110.255126
2233.160.111.0/253.160.111.1 to 3.160.111.1263.160.111.127126
2243.160.111.128/253.160.111.129 to 3.160.111.2543.160.111.255126
2253.160.112.0/253.160.112.1 to 3.160.112.1263.160.112.127126
2263.160.112.128/253.160.112.129 to 3.160.112.2543.160.112.255126
2273.160.113.0/253.160.113.1 to 3.160.113.1263.160.113.127126
2283.160.113.128/253.160.113.129 to 3.160.113.2543.160.113.255126
2293.160.114.0/253.160.114.1 to 3.160.114.1263.160.114.127126
2303.160.114.128/253.160.114.129 to 3.160.114.2543.160.114.255126
2313.160.115.0/253.160.115.1 to 3.160.115.1263.160.115.127126
2323.160.115.128/253.160.115.129 to 3.160.115.2543.160.115.255126
2333.160.116.0/253.160.116.1 to 3.160.116.1263.160.116.127126
2343.160.116.128/253.160.116.129 to 3.160.116.2543.160.116.255126
2353.160.117.0/253.160.117.1 to 3.160.117.1263.160.117.127126
2363.160.117.128/253.160.117.129 to 3.160.117.2543.160.117.255126
2373.160.118.0/253.160.118.1 to 3.160.118.1263.160.118.127126
2383.160.118.128/253.160.118.129 to 3.160.118.2543.160.118.255126
2393.160.119.0/253.160.119.1 to 3.160.119.1263.160.119.127126
2403.160.119.128/253.160.119.129 to 3.160.119.2543.160.119.255126
2413.160.120.0/253.160.120.1 to 3.160.120.1263.160.120.127126
2423.160.120.128/253.160.120.129 to 3.160.120.2543.160.120.255126
2433.160.121.0/253.160.121.1 to 3.160.121.1263.160.121.127126
2443.160.121.128/253.160.121.129 to 3.160.121.2543.160.121.255126
2453.160.122.0/253.160.122.1 to 3.160.122.1263.160.122.127126
2463.160.122.128/253.160.122.129 to 3.160.122.2543.160.122.255126
2473.160.123.0/253.160.123.1 to 3.160.123.1263.160.123.127126
2483.160.123.128/253.160.123.129 to 3.160.123.2543.160.123.255126
2493.160.124.0/253.160.124.1 to 3.160.124.1263.160.124.127126
2503.160.124.128/253.160.124.129 to 3.160.124.2543.160.124.255126
2513.160.125.0/253.160.125.1 to 3.160.125.1263.160.125.127126
2523.160.125.128/253.160.125.129 to 3.160.125.2543.160.125.255126
2533.160.126.0/253.160.126.1 to 3.160.126.1263.160.126.127126
2543.160.126.128/253.160.126.129 to 3.160.126.2543.160.126.255126
2553.160.127.0/253.160.127.1 to 3.160.127.1263.160.127.127126
2563.160.127.128/253.160.127.129 to 3.160.127.2543.160.127.255126

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.