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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.

Network5.30.0.0/18
Usable hosts16,382
Subnet mask255.255.192.0
Addresses16,384
Network address
5.30.0.0
Broadcast address
5.30.63.255
First usable
5.30.0.1
Last usable
5.30.63.254
Usable hosts
16,382 (16,384 less the network and broadcast addresses)
Subnet mask
255.255.192.0
Wildcard mask
0.0.63.255 (Cisco ACLs, OSPF)
Prefix length
/18
Type
Public public
Old class
A (default /8)
As numbers
Hex 051E0000 · Integer 85852160 to 85868543
Reverse DNS zones
0.30.5.in-addr.arpa
1.30.5.in-addr.arpa
2.30.5.in-addr.arpa
3.30.5.in-addr.arpa
4.30.5.in-addr.arpa
5.30.5.in-addr.arpa
6.30.5.in-addr.arpa
7.30.5.in-addr.arpa
8.30.5.in-addr.arpa
9.30.5.in-addr.arpa
10.30.5.in-addr.arpa
11.30.5.in-addr.arpa
12.30.5.in-addr.arpa
13.30.5.in-addr.arpa
14.30.5.in-addr.arpa
15.30.5.in-addr.arpa
and 48 more
/18 is not on a 8-bit boundary, so it takes 64 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00000101.00011110.00000000.000000005.30.0.0
Subnet mask11111111.11111111.11000000.00000000255.255.192.0
Network00000101.00011110.00000000.000000005.30.0.0
Broadcast00000101.00011110.00111111.111111115.30.63.255
Split into smaller subnets/26

5.30.0.0/18 makes 256 subnets of /26.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
15.30.0.0/265.30.0.1 to 5.30.0.625.30.0.6362
25.30.0.64/265.30.0.65 to 5.30.0.1265.30.0.12762
35.30.0.128/265.30.0.129 to 5.30.0.1905.30.0.19162
45.30.0.192/265.30.0.193 to 5.30.0.2545.30.0.25562
55.30.1.0/265.30.1.1 to 5.30.1.625.30.1.6362
65.30.1.64/265.30.1.65 to 5.30.1.1265.30.1.12762
75.30.1.128/265.30.1.129 to 5.30.1.1905.30.1.19162
85.30.1.192/265.30.1.193 to 5.30.1.2545.30.1.25562
95.30.2.0/265.30.2.1 to 5.30.2.625.30.2.6362
105.30.2.64/265.30.2.65 to 5.30.2.1265.30.2.12762
115.30.2.128/265.30.2.129 to 5.30.2.1905.30.2.19162
125.30.2.192/265.30.2.193 to 5.30.2.2545.30.2.25562
135.30.3.0/265.30.3.1 to 5.30.3.625.30.3.6362
145.30.3.64/265.30.3.65 to 5.30.3.1265.30.3.12762
155.30.3.128/265.30.3.129 to 5.30.3.1905.30.3.19162
165.30.3.192/265.30.3.193 to 5.30.3.2545.30.3.25562
175.30.4.0/265.30.4.1 to 5.30.4.625.30.4.6362
185.30.4.64/265.30.4.65 to 5.30.4.1265.30.4.12762
195.30.4.128/265.30.4.129 to 5.30.4.1905.30.4.19162
205.30.4.192/265.30.4.193 to 5.30.4.2545.30.4.25562
215.30.5.0/265.30.5.1 to 5.30.5.625.30.5.6362
225.30.5.64/265.30.5.65 to 5.30.5.1265.30.5.12762
235.30.5.128/265.30.5.129 to 5.30.5.1905.30.5.19162
245.30.5.192/265.30.5.193 to 5.30.5.2545.30.5.25562
255.30.6.0/265.30.6.1 to 5.30.6.625.30.6.6362
265.30.6.64/265.30.6.65 to 5.30.6.1265.30.6.12762
275.30.6.128/265.30.6.129 to 5.30.6.1905.30.6.19162
285.30.6.192/265.30.6.193 to 5.30.6.2545.30.6.25562
295.30.7.0/265.30.7.1 to 5.30.7.625.30.7.6362
305.30.7.64/265.30.7.65 to 5.30.7.1265.30.7.12762
315.30.7.128/265.30.7.129 to 5.30.7.1905.30.7.19162
325.30.7.192/265.30.7.193 to 5.30.7.2545.30.7.25562
335.30.8.0/265.30.8.1 to 5.30.8.625.30.8.6362
345.30.8.64/265.30.8.65 to 5.30.8.1265.30.8.12762
355.30.8.128/265.30.8.129 to 5.30.8.1905.30.8.19162
365.30.8.192/265.30.8.193 to 5.30.8.2545.30.8.25562
375.30.9.0/265.30.9.1 to 5.30.9.625.30.9.6362
385.30.9.64/265.30.9.65 to 5.30.9.1265.30.9.12762
395.30.9.128/265.30.9.129 to 5.30.9.1905.30.9.19162
405.30.9.192/265.30.9.193 to 5.30.9.2545.30.9.25562
415.30.10.0/265.30.10.1 to 5.30.10.625.30.10.6362
425.30.10.64/265.30.10.65 to 5.30.10.1265.30.10.12762
435.30.10.128/265.30.10.129 to 5.30.10.1905.30.10.19162
445.30.10.192/265.30.10.193 to 5.30.10.2545.30.10.25562
455.30.11.0/265.30.11.1 to 5.30.11.625.30.11.6362
465.30.11.64/265.30.11.65 to 5.30.11.1265.30.11.12762
475.30.11.128/265.30.11.129 to 5.30.11.1905.30.11.19162
485.30.11.192/265.30.11.193 to 5.30.11.2545.30.11.25562
495.30.12.0/265.30.12.1 to 5.30.12.625.30.12.6362
505.30.12.64/265.30.12.65 to 5.30.12.1265.30.12.12762
515.30.12.128/265.30.12.129 to 5.30.12.1905.30.12.19162
525.30.12.192/265.30.12.193 to 5.30.12.2545.30.12.25562
535.30.13.0/265.30.13.1 to 5.30.13.625.30.13.6362
545.30.13.64/265.30.13.65 to 5.30.13.1265.30.13.12762
555.30.13.128/265.30.13.129 to 5.30.13.1905.30.13.19162
565.30.13.192/265.30.13.193 to 5.30.13.2545.30.13.25562
575.30.14.0/265.30.14.1 to 5.30.14.625.30.14.6362
585.30.14.64/265.30.14.65 to 5.30.14.1265.30.14.12762
595.30.14.128/265.30.14.129 to 5.30.14.1905.30.14.19162
605.30.14.192/265.30.14.193 to 5.30.14.2545.30.14.25562
615.30.15.0/265.30.15.1 to 5.30.15.625.30.15.6362
625.30.15.64/265.30.15.65 to 5.30.15.1265.30.15.12762
635.30.15.128/265.30.15.129 to 5.30.15.1905.30.15.19162
645.30.15.192/265.30.15.193 to 5.30.15.2545.30.15.25562
655.30.16.0/265.30.16.1 to 5.30.16.625.30.16.6362
665.30.16.64/265.30.16.65 to 5.30.16.1265.30.16.12762
675.30.16.128/265.30.16.129 to 5.30.16.1905.30.16.19162
685.30.16.192/265.30.16.193 to 5.30.16.2545.30.16.25562
695.30.17.0/265.30.17.1 to 5.30.17.625.30.17.6362
705.30.17.64/265.30.17.65 to 5.30.17.1265.30.17.12762
715.30.17.128/265.30.17.129 to 5.30.17.1905.30.17.19162
725.30.17.192/265.30.17.193 to 5.30.17.2545.30.17.25562
735.30.18.0/265.30.18.1 to 5.30.18.625.30.18.6362
745.30.18.64/265.30.18.65 to 5.30.18.1265.30.18.12762
755.30.18.128/265.30.18.129 to 5.30.18.1905.30.18.19162
765.30.18.192/265.30.18.193 to 5.30.18.2545.30.18.25562
775.30.19.0/265.30.19.1 to 5.30.19.625.30.19.6362
785.30.19.64/265.30.19.65 to 5.30.19.1265.30.19.12762
795.30.19.128/265.30.19.129 to 5.30.19.1905.30.19.19162
805.30.19.192/265.30.19.193 to 5.30.19.2545.30.19.25562
815.30.20.0/265.30.20.1 to 5.30.20.625.30.20.6362
825.30.20.64/265.30.20.65 to 5.30.20.1265.30.20.12762
835.30.20.128/265.30.20.129 to 5.30.20.1905.30.20.19162
845.30.20.192/265.30.20.193 to 5.30.20.2545.30.20.25562
855.30.21.0/265.30.21.1 to 5.30.21.625.30.21.6362
865.30.21.64/265.30.21.65 to 5.30.21.1265.30.21.12762
875.30.21.128/265.30.21.129 to 5.30.21.1905.30.21.19162
885.30.21.192/265.30.21.193 to 5.30.21.2545.30.21.25562
895.30.22.0/265.30.22.1 to 5.30.22.625.30.22.6362
905.30.22.64/265.30.22.65 to 5.30.22.1265.30.22.12762
915.30.22.128/265.30.22.129 to 5.30.22.1905.30.22.19162
925.30.22.192/265.30.22.193 to 5.30.22.2545.30.22.25562
935.30.23.0/265.30.23.1 to 5.30.23.625.30.23.6362
945.30.23.64/265.30.23.65 to 5.30.23.1265.30.23.12762
955.30.23.128/265.30.23.129 to 5.30.23.1905.30.23.19162
965.30.23.192/265.30.23.193 to 5.30.23.2545.30.23.25562
975.30.24.0/265.30.24.1 to 5.30.24.625.30.24.6362
985.30.24.64/265.30.24.65 to 5.30.24.1265.30.24.12762
995.30.24.128/265.30.24.129 to 5.30.24.1905.30.24.19162
1005.30.24.192/265.30.24.193 to 5.30.24.2545.30.24.25562
1015.30.25.0/265.30.25.1 to 5.30.25.625.30.25.6362
1025.30.25.64/265.30.25.65 to 5.30.25.1265.30.25.12762
1035.30.25.128/265.30.25.129 to 5.30.25.1905.30.25.19162
1045.30.25.192/265.30.25.193 to 5.30.25.2545.30.25.25562
1055.30.26.0/265.30.26.1 to 5.30.26.625.30.26.6362
1065.30.26.64/265.30.26.65 to 5.30.26.1265.30.26.12762
1075.30.26.128/265.30.26.129 to 5.30.26.1905.30.26.19162
1085.30.26.192/265.30.26.193 to 5.30.26.2545.30.26.25562
1095.30.27.0/265.30.27.1 to 5.30.27.625.30.27.6362
1105.30.27.64/265.30.27.65 to 5.30.27.1265.30.27.12762
1115.30.27.128/265.30.27.129 to 5.30.27.1905.30.27.19162
1125.30.27.192/265.30.27.193 to 5.30.27.2545.30.27.25562
1135.30.28.0/265.30.28.1 to 5.30.28.625.30.28.6362
1145.30.28.64/265.30.28.65 to 5.30.28.1265.30.28.12762
1155.30.28.128/265.30.28.129 to 5.30.28.1905.30.28.19162
1165.30.28.192/265.30.28.193 to 5.30.28.2545.30.28.25562
1175.30.29.0/265.30.29.1 to 5.30.29.625.30.29.6362
1185.30.29.64/265.30.29.65 to 5.30.29.1265.30.29.12762
1195.30.29.128/265.30.29.129 to 5.30.29.1905.30.29.19162
1205.30.29.192/265.30.29.193 to 5.30.29.2545.30.29.25562
1215.30.30.0/265.30.30.1 to 5.30.30.625.30.30.6362
1225.30.30.64/265.30.30.65 to 5.30.30.1265.30.30.12762
1235.30.30.128/265.30.30.129 to 5.30.30.1905.30.30.19162
1245.30.30.192/265.30.30.193 to 5.30.30.2545.30.30.25562
1255.30.31.0/265.30.31.1 to 5.30.31.625.30.31.6362
1265.30.31.64/265.30.31.65 to 5.30.31.1265.30.31.12762
1275.30.31.128/265.30.31.129 to 5.30.31.1905.30.31.19162
1285.30.31.192/265.30.31.193 to 5.30.31.2545.30.31.25562
1295.30.32.0/265.30.32.1 to 5.30.32.625.30.32.6362
1305.30.32.64/265.30.32.65 to 5.30.32.1265.30.32.12762
1315.30.32.128/265.30.32.129 to 5.30.32.1905.30.32.19162
1325.30.32.192/265.30.32.193 to 5.30.32.2545.30.32.25562
1335.30.33.0/265.30.33.1 to 5.30.33.625.30.33.6362
1345.30.33.64/265.30.33.65 to 5.30.33.1265.30.33.12762
1355.30.33.128/265.30.33.129 to 5.30.33.1905.30.33.19162
1365.30.33.192/265.30.33.193 to 5.30.33.2545.30.33.25562
1375.30.34.0/265.30.34.1 to 5.30.34.625.30.34.6362
1385.30.34.64/265.30.34.65 to 5.30.34.1265.30.34.12762
1395.30.34.128/265.30.34.129 to 5.30.34.1905.30.34.19162
1405.30.34.192/265.30.34.193 to 5.30.34.2545.30.34.25562
1415.30.35.0/265.30.35.1 to 5.30.35.625.30.35.6362
1425.30.35.64/265.30.35.65 to 5.30.35.1265.30.35.12762
1435.30.35.128/265.30.35.129 to 5.30.35.1905.30.35.19162
1445.30.35.192/265.30.35.193 to 5.30.35.2545.30.35.25562
1455.30.36.0/265.30.36.1 to 5.30.36.625.30.36.6362
1465.30.36.64/265.30.36.65 to 5.30.36.1265.30.36.12762
1475.30.36.128/265.30.36.129 to 5.30.36.1905.30.36.19162
1485.30.36.192/265.30.36.193 to 5.30.36.2545.30.36.25562
1495.30.37.0/265.30.37.1 to 5.30.37.625.30.37.6362
1505.30.37.64/265.30.37.65 to 5.30.37.1265.30.37.12762
1515.30.37.128/265.30.37.129 to 5.30.37.1905.30.37.19162
1525.30.37.192/265.30.37.193 to 5.30.37.2545.30.37.25562
1535.30.38.0/265.30.38.1 to 5.30.38.625.30.38.6362
1545.30.38.64/265.30.38.65 to 5.30.38.1265.30.38.12762
1555.30.38.128/265.30.38.129 to 5.30.38.1905.30.38.19162
1565.30.38.192/265.30.38.193 to 5.30.38.2545.30.38.25562
1575.30.39.0/265.30.39.1 to 5.30.39.625.30.39.6362
1585.30.39.64/265.30.39.65 to 5.30.39.1265.30.39.12762
1595.30.39.128/265.30.39.129 to 5.30.39.1905.30.39.19162
1605.30.39.192/265.30.39.193 to 5.30.39.2545.30.39.25562
1615.30.40.0/265.30.40.1 to 5.30.40.625.30.40.6362
1625.30.40.64/265.30.40.65 to 5.30.40.1265.30.40.12762
1635.30.40.128/265.30.40.129 to 5.30.40.1905.30.40.19162
1645.30.40.192/265.30.40.193 to 5.30.40.2545.30.40.25562
1655.30.41.0/265.30.41.1 to 5.30.41.625.30.41.6362
1665.30.41.64/265.30.41.65 to 5.30.41.1265.30.41.12762
1675.30.41.128/265.30.41.129 to 5.30.41.1905.30.41.19162
1685.30.41.192/265.30.41.193 to 5.30.41.2545.30.41.25562
1695.30.42.0/265.30.42.1 to 5.30.42.625.30.42.6362
1705.30.42.64/265.30.42.65 to 5.30.42.1265.30.42.12762
1715.30.42.128/265.30.42.129 to 5.30.42.1905.30.42.19162
1725.30.42.192/265.30.42.193 to 5.30.42.2545.30.42.25562
1735.30.43.0/265.30.43.1 to 5.30.43.625.30.43.6362
1745.30.43.64/265.30.43.65 to 5.30.43.1265.30.43.12762
1755.30.43.128/265.30.43.129 to 5.30.43.1905.30.43.19162
1765.30.43.192/265.30.43.193 to 5.30.43.2545.30.43.25562
1775.30.44.0/265.30.44.1 to 5.30.44.625.30.44.6362
1785.30.44.64/265.30.44.65 to 5.30.44.1265.30.44.12762
1795.30.44.128/265.30.44.129 to 5.30.44.1905.30.44.19162
1805.30.44.192/265.30.44.193 to 5.30.44.2545.30.44.25562
1815.30.45.0/265.30.45.1 to 5.30.45.625.30.45.6362
1825.30.45.64/265.30.45.65 to 5.30.45.1265.30.45.12762
1835.30.45.128/265.30.45.129 to 5.30.45.1905.30.45.19162
1845.30.45.192/265.30.45.193 to 5.30.45.2545.30.45.25562
1855.30.46.0/265.30.46.1 to 5.30.46.625.30.46.6362
1865.30.46.64/265.30.46.65 to 5.30.46.1265.30.46.12762
1875.30.46.128/265.30.46.129 to 5.30.46.1905.30.46.19162
1885.30.46.192/265.30.46.193 to 5.30.46.2545.30.46.25562
1895.30.47.0/265.30.47.1 to 5.30.47.625.30.47.6362
1905.30.47.64/265.30.47.65 to 5.30.47.1265.30.47.12762
1915.30.47.128/265.30.47.129 to 5.30.47.1905.30.47.19162
1925.30.47.192/265.30.47.193 to 5.30.47.2545.30.47.25562
1935.30.48.0/265.30.48.1 to 5.30.48.625.30.48.6362
1945.30.48.64/265.30.48.65 to 5.30.48.1265.30.48.12762
1955.30.48.128/265.30.48.129 to 5.30.48.1905.30.48.19162
1965.30.48.192/265.30.48.193 to 5.30.48.2545.30.48.25562
1975.30.49.0/265.30.49.1 to 5.30.49.625.30.49.6362
1985.30.49.64/265.30.49.65 to 5.30.49.1265.30.49.12762
1995.30.49.128/265.30.49.129 to 5.30.49.1905.30.49.19162
2005.30.49.192/265.30.49.193 to 5.30.49.2545.30.49.25562
2015.30.50.0/265.30.50.1 to 5.30.50.625.30.50.6362
2025.30.50.64/265.30.50.65 to 5.30.50.1265.30.50.12762
2035.30.50.128/265.30.50.129 to 5.30.50.1905.30.50.19162
2045.30.50.192/265.30.50.193 to 5.30.50.2545.30.50.25562
2055.30.51.0/265.30.51.1 to 5.30.51.625.30.51.6362
2065.30.51.64/265.30.51.65 to 5.30.51.1265.30.51.12762
2075.30.51.128/265.30.51.129 to 5.30.51.1905.30.51.19162
2085.30.51.192/265.30.51.193 to 5.30.51.2545.30.51.25562
2095.30.52.0/265.30.52.1 to 5.30.52.625.30.52.6362
2105.30.52.64/265.30.52.65 to 5.30.52.1265.30.52.12762
2115.30.52.128/265.30.52.129 to 5.30.52.1905.30.52.19162
2125.30.52.192/265.30.52.193 to 5.30.52.2545.30.52.25562
2135.30.53.0/265.30.53.1 to 5.30.53.625.30.53.6362
2145.30.53.64/265.30.53.65 to 5.30.53.1265.30.53.12762
2155.30.53.128/265.30.53.129 to 5.30.53.1905.30.53.19162
2165.30.53.192/265.30.53.193 to 5.30.53.2545.30.53.25562
2175.30.54.0/265.30.54.1 to 5.30.54.625.30.54.6362
2185.30.54.64/265.30.54.65 to 5.30.54.1265.30.54.12762
2195.30.54.128/265.30.54.129 to 5.30.54.1905.30.54.19162
2205.30.54.192/265.30.54.193 to 5.30.54.2545.30.54.25562
2215.30.55.0/265.30.55.1 to 5.30.55.625.30.55.6362
2225.30.55.64/265.30.55.65 to 5.30.55.1265.30.55.12762
2235.30.55.128/265.30.55.129 to 5.30.55.1905.30.55.19162
2245.30.55.192/265.30.55.193 to 5.30.55.2545.30.55.25562
2255.30.56.0/265.30.56.1 to 5.30.56.625.30.56.6362
2265.30.56.64/265.30.56.65 to 5.30.56.1265.30.56.12762
2275.30.56.128/265.30.56.129 to 5.30.56.1905.30.56.19162
2285.30.56.192/265.30.56.193 to 5.30.56.2545.30.56.25562
2295.30.57.0/265.30.57.1 to 5.30.57.625.30.57.6362
2305.30.57.64/265.30.57.65 to 5.30.57.1265.30.57.12762
2315.30.57.128/265.30.57.129 to 5.30.57.1905.30.57.19162
2325.30.57.192/265.30.57.193 to 5.30.57.2545.30.57.25562
2335.30.58.0/265.30.58.1 to 5.30.58.625.30.58.6362
2345.30.58.64/265.30.58.65 to 5.30.58.1265.30.58.12762
2355.30.58.128/265.30.58.129 to 5.30.58.1905.30.58.19162
2365.30.58.192/265.30.58.193 to 5.30.58.2545.30.58.25562
2375.30.59.0/265.30.59.1 to 5.30.59.625.30.59.6362
2385.30.59.64/265.30.59.65 to 5.30.59.1265.30.59.12762
2395.30.59.128/265.30.59.129 to 5.30.59.1905.30.59.19162
2405.30.59.192/265.30.59.193 to 5.30.59.2545.30.59.25562
2415.30.60.0/265.30.60.1 to 5.30.60.625.30.60.6362
2425.30.60.64/265.30.60.65 to 5.30.60.1265.30.60.12762
2435.30.60.128/265.30.60.129 to 5.30.60.1905.30.60.19162
2445.30.60.192/265.30.60.193 to 5.30.60.2545.30.60.25562
2455.30.61.0/265.30.61.1 to 5.30.61.625.30.61.6362
2465.30.61.64/265.30.61.65 to 5.30.61.1265.30.61.12762
2475.30.61.128/265.30.61.129 to 5.30.61.1905.30.61.19162
2485.30.61.192/265.30.61.193 to 5.30.61.2545.30.61.25562
2495.30.62.0/265.30.62.1 to 5.30.62.625.30.62.6362
2505.30.62.64/265.30.62.65 to 5.30.62.1265.30.62.12762
2515.30.62.128/265.30.62.129 to 5.30.62.1905.30.62.19162
2525.30.62.192/265.30.62.193 to 5.30.62.2545.30.62.25562
2535.30.63.0/265.30.63.1 to 5.30.63.625.30.63.6362
2545.30.63.64/265.30.63.65 to 5.30.63.1265.30.63.12762
2555.30.63.128/265.30.63.129 to 5.30.63.1905.30.63.19162
2565.30.63.192/265.30.63.193 to 5.30.63.2545.30.63.25562

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