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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.

Prefix/118
Addresses1,024
/64 networksPart of one
Network
2c19:dd:c25:c25d:dd:dd:dd:fc00/118
First address
2c19:dd:c25:c25d:dd:dd:dd:fc00
Last address
2c19:dd:c25:c25d:dd:dd:dd:ffff
Addresses
1,024
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:fc00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
c.f.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
d.f.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
e.f.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
f.f.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
/118 is not on a 4-bit boundary, so it takes 4 /120 zones.
Split into smaller subnets/127
/119 (2)/120 (4)/121 (8)/122 (16)/124 (64)/127 (512)/128 (1,024)

2c19:dd:c25:c25d:dd:dd:dd:fc00/118 makes 512 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:fc00/1272c19:dd:c25:c25d:dd:dd:dd:fc01
22c19:dd:c25:c25d:dd:dd:dd:fc02/1272c19:dd:c25:c25d:dd:dd:dd:fc03
32c19:dd:c25:c25d:dd:dd:dd:fc04/1272c19:dd:c25:c25d:dd:dd:dd:fc05
42c19:dd:c25:c25d:dd:dd:dd:fc06/1272c19:dd:c25:c25d:dd:dd:dd:fc07
52c19:dd:c25:c25d:dd:dd:dd:fc08/1272c19:dd:c25:c25d:dd:dd:dd:fc09
62c19:dd:c25:c25d:dd:dd:dd:fc0a/1272c19:dd:c25:c25d:dd:dd:dd:fc0b
72c19:dd:c25:c25d:dd:dd:dd:fc0c/1272c19:dd:c25:c25d:dd:dd:dd:fc0d
82c19:dd:c25:c25d:dd:dd:dd:fc0e/1272c19:dd:c25:c25d:dd:dd:dd:fc0f
92c19:dd:c25:c25d:dd:dd:dd:fc10/1272c19:dd:c25:c25d:dd:dd:dd:fc11
102c19:dd:c25:c25d:dd:dd:dd:fc12/1272c19:dd:c25:c25d:dd:dd:dd:fc13
112c19:dd:c25:c25d:dd:dd:dd:fc14/1272c19:dd:c25:c25d:dd:dd:dd:fc15
122c19:dd:c25:c25d:dd:dd:dd:fc16/1272c19:dd:c25:c25d:dd:dd:dd:fc17
132c19:dd:c25:c25d:dd:dd:dd:fc18/1272c19:dd:c25:c25d:dd:dd:dd:fc19
142c19:dd:c25:c25d:dd:dd:dd:fc1a/1272c19:dd:c25:c25d:dd:dd:dd:fc1b
152c19:dd:c25:c25d:dd:dd:dd:fc1c/1272c19:dd:c25:c25d:dd:dd:dd:fc1d
162c19:dd:c25:c25d:dd:dd:dd:fc1e/1272c19:dd:c25:c25d:dd:dd:dd:fc1f
172c19:dd:c25:c25d:dd:dd:dd:fc20/1272c19:dd:c25:c25d:dd:dd:dd:fc21
182c19:dd:c25:c25d:dd:dd:dd:fc22/1272c19:dd:c25:c25d:dd:dd:dd:fc23
192c19:dd:c25:c25d:dd:dd:dd:fc24/1272c19:dd:c25:c25d:dd:dd:dd:fc25
202c19:dd:c25:c25d:dd:dd:dd:fc26/1272c19:dd:c25:c25d:dd:dd:dd:fc27
212c19:dd:c25:c25d:dd:dd:dd:fc28/1272c19:dd:c25:c25d:dd:dd:dd:fc29
222c19:dd:c25:c25d:dd:dd:dd:fc2a/1272c19:dd:c25:c25d:dd:dd:dd:fc2b
232c19:dd:c25:c25d:dd:dd:dd:fc2c/1272c19:dd:c25:c25d:dd:dd:dd:fc2d
242c19:dd:c25:c25d:dd:dd:dd:fc2e/1272c19:dd:c25:c25d:dd:dd:dd:fc2f
252c19:dd:c25:c25d:dd:dd:dd:fc30/1272c19:dd:c25:c25d:dd:dd:dd:fc31
262c19:dd:c25:c25d:dd:dd:dd:fc32/1272c19:dd:c25:c25d:dd:dd:dd:fc33
272c19:dd:c25:c25d:dd:dd:dd:fc34/1272c19:dd:c25:c25d:dd:dd:dd:fc35
282c19:dd:c25:c25d:dd:dd:dd:fc36/1272c19:dd:c25:c25d:dd:dd:dd:fc37
292c19:dd:c25:c25d:dd:dd:dd:fc38/1272c19:dd:c25:c25d:dd:dd:dd:fc39
302c19:dd:c25:c25d:dd:dd:dd:fc3a/1272c19:dd:c25:c25d:dd:dd:dd:fc3b
312c19:dd:c25:c25d:dd:dd:dd:fc3c/1272c19:dd:c25:c25d:dd:dd:dd:fc3d
322c19:dd:c25:c25d:dd:dd:dd:fc3e/1272c19:dd:c25:c25d:dd:dd:dd:fc3f
332c19:dd:c25:c25d:dd:dd:dd:fc40/1272c19:dd:c25:c25d:dd:dd:dd:fc41
342c19:dd:c25:c25d:dd:dd:dd:fc42/1272c19:dd:c25:c25d:dd:dd:dd:fc43
352c19:dd:c25:c25d:dd:dd:dd:fc44/1272c19:dd:c25:c25d:dd:dd:dd:fc45
362c19:dd:c25:c25d:dd:dd:dd:fc46/1272c19:dd:c25:c25d:dd:dd:dd:fc47
372c19:dd:c25:c25d:dd:dd:dd:fc48/1272c19:dd:c25:c25d:dd:dd:dd:fc49
382c19:dd:c25:c25d:dd:dd:dd:fc4a/1272c19:dd:c25:c25d:dd:dd:dd:fc4b
392c19:dd:c25:c25d:dd:dd:dd:fc4c/1272c19:dd:c25:c25d:dd:dd:dd:fc4d
402c19:dd:c25:c25d:dd:dd:dd:fc4e/1272c19:dd:c25:c25d:dd:dd:dd:fc4f
412c19:dd:c25:c25d:dd:dd:dd:fc50/1272c19:dd:c25:c25d:dd:dd:dd:fc51
422c19:dd:c25:c25d:dd:dd:dd:fc52/1272c19:dd:c25:c25d:dd:dd:dd:fc53
432c19:dd:c25:c25d:dd:dd:dd:fc54/1272c19:dd:c25:c25d:dd:dd:dd:fc55
442c19:dd:c25:c25d:dd:dd:dd:fc56/1272c19:dd:c25:c25d:dd:dd:dd:fc57
452c19:dd:c25:c25d:dd:dd:dd:fc58/1272c19:dd:c25:c25d:dd:dd:dd:fc59
462c19:dd:c25:c25d:dd:dd:dd:fc5a/1272c19:dd:c25:c25d:dd:dd:dd:fc5b
472c19:dd:c25:c25d:dd:dd:dd:fc5c/1272c19:dd:c25:c25d:dd:dd:dd:fc5d
482c19:dd:c25:c25d:dd:dd:dd:fc5e/1272c19:dd:c25:c25d:dd:dd:dd:fc5f
492c19:dd:c25:c25d:dd:dd:dd:fc60/1272c19:dd:c25:c25d:dd:dd:dd:fc61
502c19:dd:c25:c25d:dd:dd:dd:fc62/1272c19:dd:c25:c25d:dd:dd:dd:fc63
512c19:dd:c25:c25d:dd:dd:dd:fc64/1272c19:dd:c25:c25d:dd:dd:dd:fc65
522c19:dd:c25:c25d:dd:dd:dd:fc66/1272c19:dd:c25:c25d:dd:dd:dd:fc67
532c19:dd:c25:c25d:dd:dd:dd:fc68/1272c19:dd:c25:c25d:dd:dd:dd:fc69
542c19:dd:c25:c25d:dd:dd:dd:fc6a/1272c19:dd:c25:c25d:dd:dd:dd:fc6b
552c19:dd:c25:c25d:dd:dd:dd:fc6c/1272c19:dd:c25:c25d:dd:dd:dd:fc6d
562c19:dd:c25:c25d:dd:dd:dd:fc6e/1272c19:dd:c25:c25d:dd:dd:dd:fc6f
572c19:dd:c25:c25d:dd:dd:dd:fc70/1272c19:dd:c25:c25d:dd:dd:dd:fc71
582c19:dd:c25:c25d:dd:dd:dd:fc72/1272c19:dd:c25:c25d:dd:dd:dd:fc73
592c19:dd:c25:c25d:dd:dd:dd:fc74/1272c19:dd:c25:c25d:dd:dd:dd:fc75
602c19:dd:c25:c25d:dd:dd:dd:fc76/1272c19:dd:c25:c25d:dd:dd:dd:fc77
612c19:dd:c25:c25d:dd:dd:dd:fc78/1272c19:dd:c25:c25d:dd:dd:dd:fc79
622c19:dd:c25:c25d:dd:dd:dd:fc7a/1272c19:dd:c25:c25d:dd:dd:dd:fc7b
632c19:dd:c25:c25d:dd:dd:dd:fc7c/1272c19:dd:c25:c25d:dd:dd:dd:fc7d
642c19:dd:c25:c25d:dd:dd:dd:fc7e/1272c19:dd:c25:c25d:dd:dd:dd:fc7f
652c19:dd:c25:c25d:dd:dd:dd:fc80/1272c19:dd:c25:c25d:dd:dd:dd:fc81
662c19:dd:c25:c25d:dd:dd:dd:fc82/1272c19:dd:c25:c25d:dd:dd:dd:fc83
672c19:dd:c25:c25d:dd:dd:dd:fc84/1272c19:dd:c25:c25d:dd:dd:dd:fc85
682c19:dd:c25:c25d:dd:dd:dd:fc86/1272c19:dd:c25:c25d:dd:dd:dd:fc87
692c19:dd:c25:c25d:dd:dd:dd:fc88/1272c19:dd:c25:c25d:dd:dd:dd:fc89
702c19:dd:c25:c25d:dd:dd:dd:fc8a/1272c19:dd:c25:c25d:dd:dd:dd:fc8b
712c19:dd:c25:c25d:dd:dd:dd:fc8c/1272c19:dd:c25:c25d:dd:dd:dd:fc8d
722c19:dd:c25:c25d:dd:dd:dd:fc8e/1272c19:dd:c25:c25d:dd:dd:dd:fc8f
732c19:dd:c25:c25d:dd:dd:dd:fc90/1272c19:dd:c25:c25d:dd:dd:dd:fc91
742c19:dd:c25:c25d:dd:dd:dd:fc92/1272c19:dd:c25:c25d:dd:dd:dd:fc93
752c19:dd:c25:c25d:dd:dd:dd:fc94/1272c19:dd:c25:c25d:dd:dd:dd:fc95
762c19:dd:c25:c25d:dd:dd:dd:fc96/1272c19:dd:c25:c25d:dd:dd:dd:fc97
772c19:dd:c25:c25d:dd:dd:dd:fc98/1272c19:dd:c25:c25d:dd:dd:dd:fc99
782c19:dd:c25:c25d:dd:dd:dd:fc9a/1272c19:dd:c25:c25d:dd:dd:dd:fc9b
792c19:dd:c25:c25d:dd:dd:dd:fc9c/1272c19:dd:c25:c25d:dd:dd:dd:fc9d
802c19:dd:c25:c25d:dd:dd:dd:fc9e/1272c19:dd:c25:c25d:dd:dd:dd:fc9f
812c19:dd:c25:c25d:dd:dd:dd:fca0/1272c19:dd:c25:c25d:dd:dd:dd:fca1
822c19:dd:c25:c25d:dd:dd:dd:fca2/1272c19:dd:c25:c25d:dd:dd:dd:fca3
832c19:dd:c25:c25d:dd:dd:dd:fca4/1272c19:dd:c25:c25d:dd:dd:dd:fca5
842c19:dd:c25:c25d:dd:dd:dd:fca6/1272c19:dd:c25:c25d:dd:dd:dd:fca7
852c19:dd:c25:c25d:dd:dd:dd:fca8/1272c19:dd:c25:c25d:dd:dd:dd:fca9
862c19:dd:c25:c25d:dd:dd:dd:fcaa/1272c19:dd:c25:c25d:dd:dd:dd:fcab
872c19:dd:c25:c25d:dd:dd:dd:fcac/1272c19:dd:c25:c25d:dd:dd:dd:fcad
882c19:dd:c25:c25d:dd:dd:dd:fcae/1272c19:dd:c25:c25d:dd:dd:dd:fcaf
892c19:dd:c25:c25d:dd:dd:dd:fcb0/1272c19:dd:c25:c25d:dd:dd:dd:fcb1
902c19:dd:c25:c25d:dd:dd:dd:fcb2/1272c19:dd:c25:c25d:dd:dd:dd:fcb3
912c19:dd:c25:c25d:dd:dd:dd:fcb4/1272c19:dd:c25:c25d:dd:dd:dd:fcb5
922c19:dd:c25:c25d:dd:dd:dd:fcb6/1272c19:dd:c25:c25d:dd:dd:dd:fcb7
932c19:dd:c25:c25d:dd:dd:dd:fcb8/1272c19:dd:c25:c25d:dd:dd:dd:fcb9
942c19:dd:c25:c25d:dd:dd:dd:fcba/1272c19:dd:c25:c25d:dd:dd:dd:fcbb
952c19:dd:c25:c25d:dd:dd:dd:fcbc/1272c19:dd:c25:c25d:dd:dd:dd:fcbd
962c19:dd:c25:c25d:dd:dd:dd:fcbe/1272c19:dd:c25:c25d:dd:dd:dd:fcbf
972c19:dd:c25:c25d:dd:dd:dd:fcc0/1272c19:dd:c25:c25d:dd:dd:dd:fcc1
982c19:dd:c25:c25d:dd:dd:dd:fcc2/1272c19:dd:c25:c25d:dd:dd:dd:fcc3
992c19:dd:c25:c25d:dd:dd:dd:fcc4/1272c19:dd:c25:c25d:dd:dd:dd:fcc5
1002c19:dd:c25:c25d:dd:dd:dd:fcc6/1272c19:dd:c25:c25d:dd:dd:dd:fcc7
1012c19:dd:c25:c25d:dd:dd:dd:fcc8/1272c19:dd:c25:c25d:dd:dd:dd:fcc9
1022c19:dd:c25:c25d:dd:dd:dd:fcca/1272c19:dd:c25:c25d:dd:dd:dd:fccb
1032c19:dd:c25:c25d:dd:dd:dd:fccc/1272c19:dd:c25:c25d:dd:dd:dd:fccd
1042c19:dd:c25:c25d:dd:dd:dd:fcce/1272c19:dd:c25:c25d:dd:dd:dd:fccf
1052c19:dd:c25:c25d:dd:dd:dd:fcd0/1272c19:dd:c25:c25d:dd:dd:dd:fcd1
1062c19:dd:c25:c25d:dd:dd:dd:fcd2/1272c19:dd:c25:c25d:dd:dd:dd:fcd3
1072c19:dd:c25:c25d:dd:dd:dd:fcd4/1272c19:dd:c25:c25d:dd:dd:dd:fcd5
1082c19:dd:c25:c25d:dd:dd:dd:fcd6/1272c19:dd:c25:c25d:dd:dd:dd:fcd7
1092c19:dd:c25:c25d:dd:dd:dd:fcd8/1272c19:dd:c25:c25d:dd:dd:dd:fcd9
1102c19:dd:c25:c25d:dd:dd:dd:fcda/1272c19:dd:c25:c25d:dd:dd:dd:fcdb
1112c19:dd:c25:c25d:dd:dd:dd:fcdc/1272c19:dd:c25:c25d:dd:dd:dd:fcdd
1122c19:dd:c25:c25d:dd:dd:dd:fcde/1272c19:dd:c25:c25d:dd:dd:dd:fcdf
1132c19:dd:c25:c25d:dd:dd:dd:fce0/1272c19:dd:c25:c25d:dd:dd:dd:fce1
1142c19:dd:c25:c25d:dd:dd:dd:fce2/1272c19:dd:c25:c25d:dd:dd:dd:fce3
1152c19:dd:c25:c25d:dd:dd:dd:fce4/1272c19:dd:c25:c25d:dd:dd:dd:fce5
1162c19:dd:c25:c25d:dd:dd:dd:fce6/1272c19:dd:c25:c25d:dd:dd:dd:fce7
1172c19:dd:c25:c25d:dd:dd:dd:fce8/1272c19:dd:c25:c25d:dd:dd:dd:fce9
1182c19:dd:c25:c25d:dd:dd:dd:fcea/1272c19:dd:c25:c25d:dd:dd:dd:fceb
1192c19:dd:c25:c25d:dd:dd:dd:fcec/1272c19:dd:c25:c25d:dd:dd:dd:fced
1202c19:dd:c25:c25d:dd:dd:dd:fcee/1272c19:dd:c25:c25d:dd:dd:dd:fcef
1212c19:dd:c25:c25d:dd:dd:dd:fcf0/1272c19:dd:c25:c25d:dd:dd:dd:fcf1
1222c19:dd:c25:c25d:dd:dd:dd:fcf2/1272c19:dd:c25:c25d:dd:dd:dd:fcf3
1232c19:dd:c25:c25d:dd:dd:dd:fcf4/1272c19:dd:c25:c25d:dd:dd:dd:fcf5
1242c19:dd:c25:c25d:dd:dd:dd:fcf6/1272c19:dd:c25:c25d:dd:dd:dd:fcf7
1252c19:dd:c25:c25d:dd:dd:dd:fcf8/1272c19:dd:c25:c25d:dd:dd:dd:fcf9
1262c19:dd:c25:c25d:dd:dd:dd:fcfa/1272c19:dd:c25:c25d:dd:dd:dd:fcfb
1272c19:dd:c25:c25d:dd:dd:dd:fcfc/1272c19:dd:c25:c25d:dd:dd:dd:fcfd
1282c19:dd:c25:c25d:dd:dd:dd:fcfe/1272c19:dd:c25:c25d:dd:dd:dd:fcff
1292c19:dd:c25:c25d:dd:dd:dd:fd00/1272c19:dd:c25:c25d:dd:dd:dd:fd01
1302c19:dd:c25:c25d:dd:dd:dd:fd02/1272c19:dd:c25:c25d:dd:dd:dd:fd03
1312c19:dd:c25:c25d:dd:dd:dd:fd04/1272c19:dd:c25:c25d:dd:dd:dd:fd05
1322c19:dd:c25:c25d:dd:dd:dd:fd06/1272c19:dd:c25:c25d:dd:dd:dd:fd07
1332c19:dd:c25:c25d:dd:dd:dd:fd08/1272c19:dd:c25:c25d:dd:dd:dd:fd09
1342c19:dd:c25:c25d:dd:dd:dd:fd0a/1272c19:dd:c25:c25d:dd:dd:dd:fd0b
1352c19:dd:c25:c25d:dd:dd:dd:fd0c/1272c19:dd:c25:c25d:dd:dd:dd:fd0d
1362c19:dd:c25:c25d:dd:dd:dd:fd0e/1272c19:dd:c25:c25d:dd:dd:dd:fd0f
1372c19:dd:c25:c25d:dd:dd:dd:fd10/1272c19:dd:c25:c25d:dd:dd:dd:fd11
1382c19:dd:c25:c25d:dd:dd:dd:fd12/1272c19:dd:c25:c25d:dd:dd:dd:fd13
1392c19:dd:c25:c25d:dd:dd:dd:fd14/1272c19:dd:c25:c25d:dd:dd:dd:fd15
1402c19:dd:c25:c25d:dd:dd:dd:fd16/1272c19:dd:c25:c25d:dd:dd:dd:fd17
1412c19:dd:c25:c25d:dd:dd:dd:fd18/1272c19:dd:c25:c25d:dd:dd:dd:fd19
1422c19:dd:c25:c25d:dd:dd:dd:fd1a/1272c19:dd:c25:c25d:dd:dd:dd:fd1b
1432c19:dd:c25:c25d:dd:dd:dd:fd1c/1272c19:dd:c25:c25d:dd:dd:dd:fd1d
1442c19:dd:c25:c25d:dd:dd:dd:fd1e/1272c19:dd:c25:c25d:dd:dd:dd:fd1f
1452c19:dd:c25:c25d:dd:dd:dd:fd20/1272c19:dd:c25:c25d:dd:dd:dd:fd21
1462c19:dd:c25:c25d:dd:dd:dd:fd22/1272c19:dd:c25:c25d:dd:dd:dd:fd23
1472c19:dd:c25:c25d:dd:dd:dd:fd24/1272c19:dd:c25:c25d:dd:dd:dd:fd25
1482c19:dd:c25:c25d:dd:dd:dd:fd26/1272c19:dd:c25:c25d:dd:dd:dd:fd27
1492c19:dd:c25:c25d:dd:dd:dd:fd28/1272c19:dd:c25:c25d:dd:dd:dd:fd29
1502c19:dd:c25:c25d:dd:dd:dd:fd2a/1272c19:dd:c25:c25d:dd:dd:dd:fd2b
1512c19:dd:c25:c25d:dd:dd:dd:fd2c/1272c19:dd:c25:c25d:dd:dd:dd:fd2d
1522c19:dd:c25:c25d:dd:dd:dd:fd2e/1272c19:dd:c25:c25d:dd:dd:dd:fd2f
1532c19:dd:c25:c25d:dd:dd:dd:fd30/1272c19:dd:c25:c25d:dd:dd:dd:fd31
1542c19:dd:c25:c25d:dd:dd:dd:fd32/1272c19:dd:c25:c25d:dd:dd:dd:fd33
1552c19:dd:c25:c25d:dd:dd:dd:fd34/1272c19:dd:c25:c25d:dd:dd:dd:fd35
1562c19:dd:c25:c25d:dd:dd:dd:fd36/1272c19:dd:c25:c25d:dd:dd:dd:fd37
1572c19:dd:c25:c25d:dd:dd:dd:fd38/1272c19:dd:c25:c25d:dd:dd:dd:fd39
1582c19:dd:c25:c25d:dd:dd:dd:fd3a/1272c19:dd:c25:c25d:dd:dd:dd:fd3b
1592c19:dd:c25:c25d:dd:dd:dd:fd3c/1272c19:dd:c25:c25d:dd:dd:dd:fd3d
1602c19:dd:c25:c25d:dd:dd:dd:fd3e/1272c19:dd:c25:c25d:dd:dd:dd:fd3f
1612c19:dd:c25:c25d:dd:dd:dd:fd40/1272c19:dd:c25:c25d:dd:dd:dd:fd41
1622c19:dd:c25:c25d:dd:dd:dd:fd42/1272c19:dd:c25:c25d:dd:dd:dd:fd43
1632c19:dd:c25:c25d:dd:dd:dd:fd44/1272c19:dd:c25:c25d:dd:dd:dd:fd45
1642c19:dd:c25:c25d:dd:dd:dd:fd46/1272c19:dd:c25:c25d:dd:dd:dd:fd47
1652c19:dd:c25:c25d:dd:dd:dd:fd48/1272c19:dd:c25:c25d:dd:dd:dd:fd49
1662c19:dd:c25:c25d:dd:dd:dd:fd4a/1272c19:dd:c25:c25d:dd:dd:dd:fd4b
1672c19:dd:c25:c25d:dd:dd:dd:fd4c/1272c19:dd:c25:c25d:dd:dd:dd:fd4d
1682c19:dd:c25:c25d:dd:dd:dd:fd4e/1272c19:dd:c25:c25d:dd:dd:dd:fd4f
1692c19:dd:c25:c25d:dd:dd:dd:fd50/1272c19:dd:c25:c25d:dd:dd:dd:fd51
1702c19:dd:c25:c25d:dd:dd:dd:fd52/1272c19:dd:c25:c25d:dd:dd:dd:fd53
1712c19:dd:c25:c25d:dd:dd:dd:fd54/1272c19:dd:c25:c25d:dd:dd:dd:fd55
1722c19:dd:c25:c25d:dd:dd:dd:fd56/1272c19:dd:c25:c25d:dd:dd:dd:fd57
1732c19:dd:c25:c25d:dd:dd:dd:fd58/1272c19:dd:c25:c25d:dd:dd:dd:fd59
1742c19:dd:c25:c25d:dd:dd:dd:fd5a/1272c19:dd:c25:c25d:dd:dd:dd:fd5b
1752c19:dd:c25:c25d:dd:dd:dd:fd5c/1272c19:dd:c25:c25d:dd:dd:dd:fd5d
1762c19:dd:c25:c25d:dd:dd:dd:fd5e/1272c19:dd:c25:c25d:dd:dd:dd:fd5f
1772c19:dd:c25:c25d:dd:dd:dd:fd60/1272c19:dd:c25:c25d:dd:dd:dd:fd61
1782c19:dd:c25:c25d:dd:dd:dd:fd62/1272c19:dd:c25:c25d:dd:dd:dd:fd63
1792c19:dd:c25:c25d:dd:dd:dd:fd64/1272c19:dd:c25:c25d:dd:dd:dd:fd65
1802c19:dd:c25:c25d:dd:dd:dd:fd66/1272c19:dd:c25:c25d:dd:dd:dd:fd67
1812c19:dd:c25:c25d:dd:dd:dd:fd68/1272c19:dd:c25:c25d:dd:dd:dd:fd69
1822c19:dd:c25:c25d:dd:dd:dd:fd6a/1272c19:dd:c25:c25d:dd:dd:dd:fd6b
1832c19:dd:c25:c25d:dd:dd:dd:fd6c/1272c19:dd:c25:c25d:dd:dd:dd:fd6d
1842c19:dd:c25:c25d:dd:dd:dd:fd6e/1272c19:dd:c25:c25d:dd:dd:dd:fd6f
1852c19:dd:c25:c25d:dd:dd:dd:fd70/1272c19:dd:c25:c25d:dd:dd:dd:fd71
1862c19:dd:c25:c25d:dd:dd:dd:fd72/1272c19:dd:c25:c25d:dd:dd:dd:fd73
1872c19:dd:c25:c25d:dd:dd:dd:fd74/1272c19:dd:c25:c25d:dd:dd:dd:fd75
1882c19:dd:c25:c25d:dd:dd:dd:fd76/1272c19:dd:c25:c25d:dd:dd:dd:fd77
1892c19:dd:c25:c25d:dd:dd:dd:fd78/1272c19:dd:c25:c25d:dd:dd:dd:fd79
1902c19:dd:c25:c25d:dd:dd:dd:fd7a/1272c19:dd:c25:c25d:dd:dd:dd:fd7b
1912c19:dd:c25:c25d:dd:dd:dd:fd7c/1272c19:dd:c25:c25d:dd:dd:dd:fd7d
1922c19:dd:c25:c25d:dd:dd:dd:fd7e/1272c19:dd:c25:c25d:dd:dd:dd:fd7f
1932c19:dd:c25:c25d:dd:dd:dd:fd80/1272c19:dd:c25:c25d:dd:dd:dd:fd81
1942c19:dd:c25:c25d:dd:dd:dd:fd82/1272c19:dd:c25:c25d:dd:dd:dd:fd83
1952c19:dd:c25:c25d:dd:dd:dd:fd84/1272c19:dd:c25:c25d:dd:dd:dd:fd85
1962c19:dd:c25:c25d:dd:dd:dd:fd86/1272c19:dd:c25:c25d:dd:dd:dd:fd87
1972c19:dd:c25:c25d:dd:dd:dd:fd88/1272c19:dd:c25:c25d:dd:dd:dd:fd89
1982c19:dd:c25:c25d:dd:dd:dd:fd8a/1272c19:dd:c25:c25d:dd:dd:dd:fd8b
1992c19:dd:c25:c25d:dd:dd:dd:fd8c/1272c19:dd:c25:c25d:dd:dd:dd:fd8d
2002c19:dd:c25:c25d:dd:dd:dd:fd8e/1272c19:dd:c25:c25d:dd:dd:dd:fd8f
2012c19:dd:c25:c25d:dd:dd:dd:fd90/1272c19:dd:c25:c25d:dd:dd:dd:fd91
2022c19:dd:c25:c25d:dd:dd:dd:fd92/1272c19:dd:c25:c25d:dd:dd:dd:fd93
2032c19:dd:c25:c25d:dd:dd:dd:fd94/1272c19:dd:c25:c25d:dd:dd:dd:fd95
2042c19:dd:c25:c25d:dd:dd:dd:fd96/1272c19:dd:c25:c25d:dd:dd:dd:fd97
2052c19:dd:c25:c25d:dd:dd:dd:fd98/1272c19:dd:c25:c25d:dd:dd:dd:fd99
2062c19:dd:c25:c25d:dd:dd:dd:fd9a/1272c19:dd:c25:c25d:dd:dd:dd:fd9b
2072c19:dd:c25:c25d:dd:dd:dd:fd9c/1272c19:dd:c25:c25d:dd:dd:dd:fd9d
2082c19:dd:c25:c25d:dd:dd:dd:fd9e/1272c19:dd:c25:c25d:dd:dd:dd:fd9f
2092c19:dd:c25:c25d:dd:dd:dd:fda0/1272c19:dd:c25:c25d:dd:dd:dd:fda1
2102c19:dd:c25:c25d:dd:dd:dd:fda2/1272c19:dd:c25:c25d:dd:dd:dd:fda3
2112c19:dd:c25:c25d:dd:dd:dd:fda4/1272c19:dd:c25:c25d:dd:dd:dd:fda5
2122c19:dd:c25:c25d:dd:dd:dd:fda6/1272c19:dd:c25:c25d:dd:dd:dd:fda7
2132c19:dd:c25:c25d:dd:dd:dd:fda8/1272c19:dd:c25:c25d:dd:dd:dd:fda9
2142c19:dd:c25:c25d:dd:dd:dd:fdaa/1272c19:dd:c25:c25d:dd:dd:dd:fdab
2152c19:dd:c25:c25d:dd:dd:dd:fdac/1272c19:dd:c25:c25d:dd:dd:dd:fdad
2162c19:dd:c25:c25d:dd:dd:dd:fdae/1272c19:dd:c25:c25d:dd:dd:dd:fdaf
2172c19:dd:c25:c25d:dd:dd:dd:fdb0/1272c19:dd:c25:c25d:dd:dd:dd:fdb1
2182c19:dd:c25:c25d:dd:dd:dd:fdb2/1272c19:dd:c25:c25d:dd:dd:dd:fdb3
2192c19:dd:c25:c25d:dd:dd:dd:fdb4/1272c19:dd:c25:c25d:dd:dd:dd:fdb5
2202c19:dd:c25:c25d:dd:dd:dd:fdb6/1272c19:dd:c25:c25d:dd:dd:dd:fdb7
2212c19:dd:c25:c25d:dd:dd:dd:fdb8/1272c19:dd:c25:c25d:dd:dd:dd:fdb9
2222c19:dd:c25:c25d:dd:dd:dd:fdba/1272c19:dd:c25:c25d:dd:dd:dd:fdbb
2232c19:dd:c25:c25d:dd:dd:dd:fdbc/1272c19:dd:c25:c25d:dd:dd:dd:fdbd
2242c19:dd:c25:c25d:dd:dd:dd:fdbe/1272c19:dd:c25:c25d:dd:dd:dd:fdbf
2252c19:dd:c25:c25d:dd:dd:dd:fdc0/1272c19:dd:c25:c25d:dd:dd:dd:fdc1
2262c19:dd:c25:c25d:dd:dd:dd:fdc2/1272c19:dd:c25:c25d:dd:dd:dd:fdc3
2272c19:dd:c25:c25d:dd:dd:dd:fdc4/1272c19:dd:c25:c25d:dd:dd:dd:fdc5
2282c19:dd:c25:c25d:dd:dd:dd:fdc6/1272c19:dd:c25:c25d:dd:dd:dd:fdc7
2292c19:dd:c25:c25d:dd:dd:dd:fdc8/1272c19:dd:c25:c25d:dd:dd:dd:fdc9
2302c19:dd:c25:c25d:dd:dd:dd:fdca/1272c19:dd:c25:c25d:dd:dd:dd:fdcb
2312c19:dd:c25:c25d:dd:dd:dd:fdcc/1272c19:dd:c25:c25d:dd:dd:dd:fdcd
2322c19:dd:c25:c25d:dd:dd:dd:fdce/1272c19:dd:c25:c25d:dd:dd:dd:fdcf
2332c19:dd:c25:c25d:dd:dd:dd:fdd0/1272c19:dd:c25:c25d:dd:dd:dd:fdd1
2342c19:dd:c25:c25d:dd:dd:dd:fdd2/1272c19:dd:c25:c25d:dd:dd:dd:fdd3
2352c19:dd:c25:c25d:dd:dd:dd:fdd4/1272c19:dd:c25:c25d:dd:dd:dd:fdd5
2362c19:dd:c25:c25d:dd:dd:dd:fdd6/1272c19:dd:c25:c25d:dd:dd:dd:fdd7
2372c19:dd:c25:c25d:dd:dd:dd:fdd8/1272c19:dd:c25:c25d:dd:dd:dd:fdd9
2382c19:dd:c25:c25d:dd:dd:dd:fdda/1272c19:dd:c25:c25d:dd:dd:dd:fddb
2392c19:dd:c25:c25d:dd:dd:dd:fddc/1272c19:dd:c25:c25d:dd:dd:dd:fddd
2402c19:dd:c25:c25d:dd:dd:dd:fdde/1272c19:dd:c25:c25d:dd:dd:dd:fddf
2412c19:dd:c25:c25d:dd:dd:dd:fde0/1272c19:dd:c25:c25d:dd:dd:dd:fde1
2422c19:dd:c25:c25d:dd:dd:dd:fde2/1272c19:dd:c25:c25d:dd:dd:dd:fde3
2432c19:dd:c25:c25d:dd:dd:dd:fde4/1272c19:dd:c25:c25d:dd:dd:dd:fde5
2442c19:dd:c25:c25d:dd:dd:dd:fde6/1272c19:dd:c25:c25d:dd:dd:dd:fde7
2452c19:dd:c25:c25d:dd:dd:dd:fde8/1272c19:dd:c25:c25d:dd:dd:dd:fde9
2462c19:dd:c25:c25d:dd:dd:dd:fdea/1272c19:dd:c25:c25d:dd:dd:dd:fdeb
2472c19:dd:c25:c25d:dd:dd:dd:fdec/1272c19:dd:c25:c25d:dd:dd:dd:fded
2482c19:dd:c25:c25d:dd:dd:dd:fdee/1272c19:dd:c25:c25d:dd:dd:dd:fdef
2492c19:dd:c25:c25d:dd:dd:dd:fdf0/1272c19:dd:c25:c25d:dd:dd:dd:fdf1
2502c19:dd:c25:c25d:dd:dd:dd:fdf2/1272c19:dd:c25:c25d:dd:dd:dd:fdf3
2512c19:dd:c25:c25d:dd:dd:dd:fdf4/1272c19:dd:c25:c25d:dd:dd:dd:fdf5
2522c19:dd:c25:c25d:dd:dd:dd:fdf6/1272c19:dd:c25:c25d:dd:dd:dd:fdf7
2532c19:dd:c25:c25d:dd:dd:dd:fdf8/1272c19:dd:c25:c25d:dd:dd:dd:fdf9
2542c19:dd:c25:c25d:dd:dd:dd:fdfa/1272c19:dd:c25:c25d:dd:dd:dd:fdfb
2552c19:dd:c25:c25d:dd:dd:dd:fdfc/1272c19:dd:c25:c25d:dd:dd:dd:fdfd
2562c19:dd:c25:c25d:dd:dd:dd:fdfe/1272c19:dd:c25:c25d:dd:dd:dd:fdff

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.