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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.

Network0.48.128.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
0.48.128.0
Broadcast address
0.48.255.255
First usable
0.48.128.1
Last usable
0.48.255.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
This network 0.0.0.0/8
Not routed; 0.0.0.0 means "any address" in settings
Old class
A (default /8)
As numbers
Hex 00308000 · Integer 3178496 to 3211263
Reverse DNS zones
128.48.0.in-addr.arpa
129.48.0.in-addr.arpa
130.48.0.in-addr.arpa
131.48.0.in-addr.arpa
132.48.0.in-addr.arpa
133.48.0.in-addr.arpa
134.48.0.in-addr.arpa
135.48.0.in-addr.arpa
136.48.0.in-addr.arpa
137.48.0.in-addr.arpa
138.48.0.in-addr.arpa
139.48.0.in-addr.arpa
140.48.0.in-addr.arpa
141.48.0.in-addr.arpa
142.48.0.in-addr.arpa
143.48.0.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00000000.00110000.10000000.000000000.48.128.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network00000000.00110000.10000000.000000000.48.128.0
Broadcast00000000.00110000.11111111.111111110.48.255.255
Split into smaller subnets/27

0.48.128.0/17 makes 1,024 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
10.48.128.0/270.48.128.1 to 0.48.128.300.48.128.3130
20.48.128.32/270.48.128.33 to 0.48.128.620.48.128.6330
30.48.128.64/270.48.128.65 to 0.48.128.940.48.128.9530
40.48.128.96/270.48.128.97 to 0.48.128.1260.48.128.12730
50.48.128.128/270.48.128.129 to 0.48.128.1580.48.128.15930
60.48.128.160/270.48.128.161 to 0.48.128.1900.48.128.19130
70.48.128.192/270.48.128.193 to 0.48.128.2220.48.128.22330
80.48.128.224/270.48.128.225 to 0.48.128.2540.48.128.25530
90.48.129.0/270.48.129.1 to 0.48.129.300.48.129.3130
100.48.129.32/270.48.129.33 to 0.48.129.620.48.129.6330
110.48.129.64/270.48.129.65 to 0.48.129.940.48.129.9530
120.48.129.96/270.48.129.97 to 0.48.129.1260.48.129.12730
130.48.129.128/270.48.129.129 to 0.48.129.1580.48.129.15930
140.48.129.160/270.48.129.161 to 0.48.129.1900.48.129.19130
150.48.129.192/270.48.129.193 to 0.48.129.2220.48.129.22330
160.48.129.224/270.48.129.225 to 0.48.129.2540.48.129.25530
170.48.130.0/270.48.130.1 to 0.48.130.300.48.130.3130
180.48.130.32/270.48.130.33 to 0.48.130.620.48.130.6330
190.48.130.64/270.48.130.65 to 0.48.130.940.48.130.9530
200.48.130.96/270.48.130.97 to 0.48.130.1260.48.130.12730
210.48.130.128/270.48.130.129 to 0.48.130.1580.48.130.15930
220.48.130.160/270.48.130.161 to 0.48.130.1900.48.130.19130
230.48.130.192/270.48.130.193 to 0.48.130.2220.48.130.22330
240.48.130.224/270.48.130.225 to 0.48.130.2540.48.130.25530
250.48.131.0/270.48.131.1 to 0.48.131.300.48.131.3130
260.48.131.32/270.48.131.33 to 0.48.131.620.48.131.6330
270.48.131.64/270.48.131.65 to 0.48.131.940.48.131.9530
280.48.131.96/270.48.131.97 to 0.48.131.1260.48.131.12730
290.48.131.128/270.48.131.129 to 0.48.131.1580.48.131.15930
300.48.131.160/270.48.131.161 to 0.48.131.1900.48.131.19130
310.48.131.192/270.48.131.193 to 0.48.131.2220.48.131.22330
320.48.131.224/270.48.131.225 to 0.48.131.2540.48.131.25530
330.48.132.0/270.48.132.1 to 0.48.132.300.48.132.3130
340.48.132.32/270.48.132.33 to 0.48.132.620.48.132.6330
350.48.132.64/270.48.132.65 to 0.48.132.940.48.132.9530
360.48.132.96/270.48.132.97 to 0.48.132.1260.48.132.12730
370.48.132.128/270.48.132.129 to 0.48.132.1580.48.132.15930
380.48.132.160/270.48.132.161 to 0.48.132.1900.48.132.19130
390.48.132.192/270.48.132.193 to 0.48.132.2220.48.132.22330
400.48.132.224/270.48.132.225 to 0.48.132.2540.48.132.25530
410.48.133.0/270.48.133.1 to 0.48.133.300.48.133.3130
420.48.133.32/270.48.133.33 to 0.48.133.620.48.133.6330
430.48.133.64/270.48.133.65 to 0.48.133.940.48.133.9530
440.48.133.96/270.48.133.97 to 0.48.133.1260.48.133.12730
450.48.133.128/270.48.133.129 to 0.48.133.1580.48.133.15930
460.48.133.160/270.48.133.161 to 0.48.133.1900.48.133.19130
470.48.133.192/270.48.133.193 to 0.48.133.2220.48.133.22330
480.48.133.224/270.48.133.225 to 0.48.133.2540.48.133.25530
490.48.134.0/270.48.134.1 to 0.48.134.300.48.134.3130
500.48.134.32/270.48.134.33 to 0.48.134.620.48.134.6330
510.48.134.64/270.48.134.65 to 0.48.134.940.48.134.9530
520.48.134.96/270.48.134.97 to 0.48.134.1260.48.134.12730
530.48.134.128/270.48.134.129 to 0.48.134.1580.48.134.15930
540.48.134.160/270.48.134.161 to 0.48.134.1900.48.134.19130
550.48.134.192/270.48.134.193 to 0.48.134.2220.48.134.22330
560.48.134.224/270.48.134.225 to 0.48.134.2540.48.134.25530
570.48.135.0/270.48.135.1 to 0.48.135.300.48.135.3130
580.48.135.32/270.48.135.33 to 0.48.135.620.48.135.6330
590.48.135.64/270.48.135.65 to 0.48.135.940.48.135.9530
600.48.135.96/270.48.135.97 to 0.48.135.1260.48.135.12730
610.48.135.128/270.48.135.129 to 0.48.135.1580.48.135.15930
620.48.135.160/270.48.135.161 to 0.48.135.1900.48.135.19130
630.48.135.192/270.48.135.193 to 0.48.135.2220.48.135.22330
640.48.135.224/270.48.135.225 to 0.48.135.2540.48.135.25530
650.48.136.0/270.48.136.1 to 0.48.136.300.48.136.3130
660.48.136.32/270.48.136.33 to 0.48.136.620.48.136.6330
670.48.136.64/270.48.136.65 to 0.48.136.940.48.136.9530
680.48.136.96/270.48.136.97 to 0.48.136.1260.48.136.12730
690.48.136.128/270.48.136.129 to 0.48.136.1580.48.136.15930
700.48.136.160/270.48.136.161 to 0.48.136.1900.48.136.19130
710.48.136.192/270.48.136.193 to 0.48.136.2220.48.136.22330
720.48.136.224/270.48.136.225 to 0.48.136.2540.48.136.25530
730.48.137.0/270.48.137.1 to 0.48.137.300.48.137.3130
740.48.137.32/270.48.137.33 to 0.48.137.620.48.137.6330
750.48.137.64/270.48.137.65 to 0.48.137.940.48.137.9530
760.48.137.96/270.48.137.97 to 0.48.137.1260.48.137.12730
770.48.137.128/270.48.137.129 to 0.48.137.1580.48.137.15930
780.48.137.160/270.48.137.161 to 0.48.137.1900.48.137.19130
790.48.137.192/270.48.137.193 to 0.48.137.2220.48.137.22330
800.48.137.224/270.48.137.225 to 0.48.137.2540.48.137.25530
810.48.138.0/270.48.138.1 to 0.48.138.300.48.138.3130
820.48.138.32/270.48.138.33 to 0.48.138.620.48.138.6330
830.48.138.64/270.48.138.65 to 0.48.138.940.48.138.9530
840.48.138.96/270.48.138.97 to 0.48.138.1260.48.138.12730
850.48.138.128/270.48.138.129 to 0.48.138.1580.48.138.15930
860.48.138.160/270.48.138.161 to 0.48.138.1900.48.138.19130
870.48.138.192/270.48.138.193 to 0.48.138.2220.48.138.22330
880.48.138.224/270.48.138.225 to 0.48.138.2540.48.138.25530
890.48.139.0/270.48.139.1 to 0.48.139.300.48.139.3130
900.48.139.32/270.48.139.33 to 0.48.139.620.48.139.6330
910.48.139.64/270.48.139.65 to 0.48.139.940.48.139.9530
920.48.139.96/270.48.139.97 to 0.48.139.1260.48.139.12730
930.48.139.128/270.48.139.129 to 0.48.139.1580.48.139.15930
940.48.139.160/270.48.139.161 to 0.48.139.1900.48.139.19130
950.48.139.192/270.48.139.193 to 0.48.139.2220.48.139.22330
960.48.139.224/270.48.139.225 to 0.48.139.2540.48.139.25530
970.48.140.0/270.48.140.1 to 0.48.140.300.48.140.3130
980.48.140.32/270.48.140.33 to 0.48.140.620.48.140.6330
990.48.140.64/270.48.140.65 to 0.48.140.940.48.140.9530
1000.48.140.96/270.48.140.97 to 0.48.140.1260.48.140.12730
1010.48.140.128/270.48.140.129 to 0.48.140.1580.48.140.15930
1020.48.140.160/270.48.140.161 to 0.48.140.1900.48.140.19130
1030.48.140.192/270.48.140.193 to 0.48.140.2220.48.140.22330
1040.48.140.224/270.48.140.225 to 0.48.140.2540.48.140.25530
1050.48.141.0/270.48.141.1 to 0.48.141.300.48.141.3130
1060.48.141.32/270.48.141.33 to 0.48.141.620.48.141.6330
1070.48.141.64/270.48.141.65 to 0.48.141.940.48.141.9530
1080.48.141.96/270.48.141.97 to 0.48.141.1260.48.141.12730
1090.48.141.128/270.48.141.129 to 0.48.141.1580.48.141.15930
1100.48.141.160/270.48.141.161 to 0.48.141.1900.48.141.19130
1110.48.141.192/270.48.141.193 to 0.48.141.2220.48.141.22330
1120.48.141.224/270.48.141.225 to 0.48.141.2540.48.141.25530
1130.48.142.0/270.48.142.1 to 0.48.142.300.48.142.3130
1140.48.142.32/270.48.142.33 to 0.48.142.620.48.142.6330
1150.48.142.64/270.48.142.65 to 0.48.142.940.48.142.9530
1160.48.142.96/270.48.142.97 to 0.48.142.1260.48.142.12730
1170.48.142.128/270.48.142.129 to 0.48.142.1580.48.142.15930
1180.48.142.160/270.48.142.161 to 0.48.142.1900.48.142.19130
1190.48.142.192/270.48.142.193 to 0.48.142.2220.48.142.22330
1200.48.142.224/270.48.142.225 to 0.48.142.2540.48.142.25530
1210.48.143.0/270.48.143.1 to 0.48.143.300.48.143.3130
1220.48.143.32/270.48.143.33 to 0.48.143.620.48.143.6330
1230.48.143.64/270.48.143.65 to 0.48.143.940.48.143.9530
1240.48.143.96/270.48.143.97 to 0.48.143.1260.48.143.12730
1250.48.143.128/270.48.143.129 to 0.48.143.1580.48.143.15930
1260.48.143.160/270.48.143.161 to 0.48.143.1900.48.143.19130
1270.48.143.192/270.48.143.193 to 0.48.143.2220.48.143.22330
1280.48.143.224/270.48.143.225 to 0.48.143.2540.48.143.25530
1290.48.144.0/270.48.144.1 to 0.48.144.300.48.144.3130
1300.48.144.32/270.48.144.33 to 0.48.144.620.48.144.6330
1310.48.144.64/270.48.144.65 to 0.48.144.940.48.144.9530
1320.48.144.96/270.48.144.97 to 0.48.144.1260.48.144.12730
1330.48.144.128/270.48.144.129 to 0.48.144.1580.48.144.15930
1340.48.144.160/270.48.144.161 to 0.48.144.1900.48.144.19130
1350.48.144.192/270.48.144.193 to 0.48.144.2220.48.144.22330
1360.48.144.224/270.48.144.225 to 0.48.144.2540.48.144.25530
1370.48.145.0/270.48.145.1 to 0.48.145.300.48.145.3130
1380.48.145.32/270.48.145.33 to 0.48.145.620.48.145.6330
1390.48.145.64/270.48.145.65 to 0.48.145.940.48.145.9530
1400.48.145.96/270.48.145.97 to 0.48.145.1260.48.145.12730
1410.48.145.128/270.48.145.129 to 0.48.145.1580.48.145.15930
1420.48.145.160/270.48.145.161 to 0.48.145.1900.48.145.19130
1430.48.145.192/270.48.145.193 to 0.48.145.2220.48.145.22330
1440.48.145.224/270.48.145.225 to 0.48.145.2540.48.145.25530
1450.48.146.0/270.48.146.1 to 0.48.146.300.48.146.3130
1460.48.146.32/270.48.146.33 to 0.48.146.620.48.146.6330
1470.48.146.64/270.48.146.65 to 0.48.146.940.48.146.9530
1480.48.146.96/270.48.146.97 to 0.48.146.1260.48.146.12730
1490.48.146.128/270.48.146.129 to 0.48.146.1580.48.146.15930
1500.48.146.160/270.48.146.161 to 0.48.146.1900.48.146.19130
1510.48.146.192/270.48.146.193 to 0.48.146.2220.48.146.22330
1520.48.146.224/270.48.146.225 to 0.48.146.2540.48.146.25530
1530.48.147.0/270.48.147.1 to 0.48.147.300.48.147.3130
1540.48.147.32/270.48.147.33 to 0.48.147.620.48.147.6330
1550.48.147.64/270.48.147.65 to 0.48.147.940.48.147.9530
1560.48.147.96/270.48.147.97 to 0.48.147.1260.48.147.12730
1570.48.147.128/270.48.147.129 to 0.48.147.1580.48.147.15930
1580.48.147.160/270.48.147.161 to 0.48.147.1900.48.147.19130
1590.48.147.192/270.48.147.193 to 0.48.147.2220.48.147.22330
1600.48.147.224/270.48.147.225 to 0.48.147.2540.48.147.25530
1610.48.148.0/270.48.148.1 to 0.48.148.300.48.148.3130
1620.48.148.32/270.48.148.33 to 0.48.148.620.48.148.6330
1630.48.148.64/270.48.148.65 to 0.48.148.940.48.148.9530
1640.48.148.96/270.48.148.97 to 0.48.148.1260.48.148.12730
1650.48.148.128/270.48.148.129 to 0.48.148.1580.48.148.15930
1660.48.148.160/270.48.148.161 to 0.48.148.1900.48.148.19130
1670.48.148.192/270.48.148.193 to 0.48.148.2220.48.148.22330
1680.48.148.224/270.48.148.225 to 0.48.148.2540.48.148.25530
1690.48.149.0/270.48.149.1 to 0.48.149.300.48.149.3130
1700.48.149.32/270.48.149.33 to 0.48.149.620.48.149.6330
1710.48.149.64/270.48.149.65 to 0.48.149.940.48.149.9530
1720.48.149.96/270.48.149.97 to 0.48.149.1260.48.149.12730
1730.48.149.128/270.48.149.129 to 0.48.149.1580.48.149.15930
1740.48.149.160/270.48.149.161 to 0.48.149.1900.48.149.19130
1750.48.149.192/270.48.149.193 to 0.48.149.2220.48.149.22330
1760.48.149.224/270.48.149.225 to 0.48.149.2540.48.149.25530
1770.48.150.0/270.48.150.1 to 0.48.150.300.48.150.3130
1780.48.150.32/270.48.150.33 to 0.48.150.620.48.150.6330
1790.48.150.64/270.48.150.65 to 0.48.150.940.48.150.9530
1800.48.150.96/270.48.150.97 to 0.48.150.1260.48.150.12730
1810.48.150.128/270.48.150.129 to 0.48.150.1580.48.150.15930
1820.48.150.160/270.48.150.161 to 0.48.150.1900.48.150.19130
1830.48.150.192/270.48.150.193 to 0.48.150.2220.48.150.22330
1840.48.150.224/270.48.150.225 to 0.48.150.2540.48.150.25530
1850.48.151.0/270.48.151.1 to 0.48.151.300.48.151.3130
1860.48.151.32/270.48.151.33 to 0.48.151.620.48.151.6330
1870.48.151.64/270.48.151.65 to 0.48.151.940.48.151.9530
1880.48.151.96/270.48.151.97 to 0.48.151.1260.48.151.12730
1890.48.151.128/270.48.151.129 to 0.48.151.1580.48.151.15930
1900.48.151.160/270.48.151.161 to 0.48.151.1900.48.151.19130
1910.48.151.192/270.48.151.193 to 0.48.151.2220.48.151.22330
1920.48.151.224/270.48.151.225 to 0.48.151.2540.48.151.25530
1930.48.152.0/270.48.152.1 to 0.48.152.300.48.152.3130
1940.48.152.32/270.48.152.33 to 0.48.152.620.48.152.6330
1950.48.152.64/270.48.152.65 to 0.48.152.940.48.152.9530
1960.48.152.96/270.48.152.97 to 0.48.152.1260.48.152.12730
1970.48.152.128/270.48.152.129 to 0.48.152.1580.48.152.15930
1980.48.152.160/270.48.152.161 to 0.48.152.1900.48.152.19130
1990.48.152.192/270.48.152.193 to 0.48.152.2220.48.152.22330
2000.48.152.224/270.48.152.225 to 0.48.152.2540.48.152.25530
2010.48.153.0/270.48.153.1 to 0.48.153.300.48.153.3130
2020.48.153.32/270.48.153.33 to 0.48.153.620.48.153.6330
2030.48.153.64/270.48.153.65 to 0.48.153.940.48.153.9530
2040.48.153.96/270.48.153.97 to 0.48.153.1260.48.153.12730
2050.48.153.128/270.48.153.129 to 0.48.153.1580.48.153.15930
2060.48.153.160/270.48.153.161 to 0.48.153.1900.48.153.19130
2070.48.153.192/270.48.153.193 to 0.48.153.2220.48.153.22330
2080.48.153.224/270.48.153.225 to 0.48.153.2540.48.153.25530
2090.48.154.0/270.48.154.1 to 0.48.154.300.48.154.3130
2100.48.154.32/270.48.154.33 to 0.48.154.620.48.154.6330
2110.48.154.64/270.48.154.65 to 0.48.154.940.48.154.9530
2120.48.154.96/270.48.154.97 to 0.48.154.1260.48.154.12730
2130.48.154.128/270.48.154.129 to 0.48.154.1580.48.154.15930
2140.48.154.160/270.48.154.161 to 0.48.154.1900.48.154.19130
2150.48.154.192/270.48.154.193 to 0.48.154.2220.48.154.22330
2160.48.154.224/270.48.154.225 to 0.48.154.2540.48.154.25530
2170.48.155.0/270.48.155.1 to 0.48.155.300.48.155.3130
2180.48.155.32/270.48.155.33 to 0.48.155.620.48.155.6330
2190.48.155.64/270.48.155.65 to 0.48.155.940.48.155.9530
2200.48.155.96/270.48.155.97 to 0.48.155.1260.48.155.12730
2210.48.155.128/270.48.155.129 to 0.48.155.1580.48.155.15930
2220.48.155.160/270.48.155.161 to 0.48.155.1900.48.155.19130
2230.48.155.192/270.48.155.193 to 0.48.155.2220.48.155.22330
2240.48.155.224/270.48.155.225 to 0.48.155.2540.48.155.25530
2250.48.156.0/270.48.156.1 to 0.48.156.300.48.156.3130
2260.48.156.32/270.48.156.33 to 0.48.156.620.48.156.6330
2270.48.156.64/270.48.156.65 to 0.48.156.940.48.156.9530
2280.48.156.96/270.48.156.97 to 0.48.156.1260.48.156.12730
2290.48.156.128/270.48.156.129 to 0.48.156.1580.48.156.15930
2300.48.156.160/270.48.156.161 to 0.48.156.1900.48.156.19130
2310.48.156.192/270.48.156.193 to 0.48.156.2220.48.156.22330
2320.48.156.224/270.48.156.225 to 0.48.156.2540.48.156.25530
2330.48.157.0/270.48.157.1 to 0.48.157.300.48.157.3130
2340.48.157.32/270.48.157.33 to 0.48.157.620.48.157.6330
2350.48.157.64/270.48.157.65 to 0.48.157.940.48.157.9530
2360.48.157.96/270.48.157.97 to 0.48.157.1260.48.157.12730
2370.48.157.128/270.48.157.129 to 0.48.157.1580.48.157.15930
2380.48.157.160/270.48.157.161 to 0.48.157.1900.48.157.19130
2390.48.157.192/270.48.157.193 to 0.48.157.2220.48.157.22330
2400.48.157.224/270.48.157.225 to 0.48.157.2540.48.157.25530
2410.48.158.0/270.48.158.1 to 0.48.158.300.48.158.3130
2420.48.158.32/270.48.158.33 to 0.48.158.620.48.158.6330
2430.48.158.64/270.48.158.65 to 0.48.158.940.48.158.9530
2440.48.158.96/270.48.158.97 to 0.48.158.1260.48.158.12730
2450.48.158.128/270.48.158.129 to 0.48.158.1580.48.158.15930
2460.48.158.160/270.48.158.161 to 0.48.158.1900.48.158.19130
2470.48.158.192/270.48.158.193 to 0.48.158.2220.48.158.22330
2480.48.158.224/270.48.158.225 to 0.48.158.2540.48.158.25530
2490.48.159.0/270.48.159.1 to 0.48.159.300.48.159.3130
2500.48.159.32/270.48.159.33 to 0.48.159.620.48.159.6330
2510.48.159.64/270.48.159.65 to 0.48.159.940.48.159.9530
2520.48.159.96/270.48.159.97 to 0.48.159.1260.48.159.12730
2530.48.159.128/270.48.159.129 to 0.48.159.1580.48.159.15930
2540.48.159.160/270.48.159.161 to 0.48.159.1900.48.159.19130
2550.48.159.192/270.48.159.193 to 0.48.159.2220.48.159.22330
2560.48.159.224/270.48.159.225 to 0.48.159.2540.48.159.25530

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