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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:c25:c25:dd:dd:dd:ca00/119
First address
2c19:dd:c25:c25:dd:dd:dd:ca00
Last address
2c19:dd:c25:c25:dd:dd:dd:cbff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:0c25:00dd:00dd:00dd:ca00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
a.c.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
b.c.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:c25:c25:dd:dd:dd:ca00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:c25:c25:dd:dd:dd:ca00/1272c19:dd:c25:c25:dd:dd:dd:ca01
22c19:dd:c25:c25:dd:dd:dd:ca02/1272c19:dd:c25:c25:dd:dd:dd:ca03
32c19:dd:c25:c25:dd:dd:dd:ca04/1272c19:dd:c25:c25:dd:dd:dd:ca05
42c19:dd:c25:c25:dd:dd:dd:ca06/1272c19:dd:c25:c25:dd:dd:dd:ca07
52c19:dd:c25:c25:dd:dd:dd:ca08/1272c19:dd:c25:c25:dd:dd:dd:ca09
62c19:dd:c25:c25:dd:dd:dd:ca0a/1272c19:dd:c25:c25:dd:dd:dd:ca0b
72c19:dd:c25:c25:dd:dd:dd:ca0c/1272c19:dd:c25:c25:dd:dd:dd:ca0d
82c19:dd:c25:c25:dd:dd:dd:ca0e/1272c19:dd:c25:c25:dd:dd:dd:ca0f
92c19:dd:c25:c25:dd:dd:dd:ca10/1272c19:dd:c25:c25:dd:dd:dd:ca11
102c19:dd:c25:c25:dd:dd:dd:ca12/1272c19:dd:c25:c25:dd:dd:dd:ca13
112c19:dd:c25:c25:dd:dd:dd:ca14/1272c19:dd:c25:c25:dd:dd:dd:ca15
122c19:dd:c25:c25:dd:dd:dd:ca16/1272c19:dd:c25:c25:dd:dd:dd:ca17
132c19:dd:c25:c25:dd:dd:dd:ca18/1272c19:dd:c25:c25:dd:dd:dd:ca19
142c19:dd:c25:c25:dd:dd:dd:ca1a/1272c19:dd:c25:c25:dd:dd:dd:ca1b
152c19:dd:c25:c25:dd:dd:dd:ca1c/1272c19:dd:c25:c25:dd:dd:dd:ca1d
162c19:dd:c25:c25:dd:dd:dd:ca1e/1272c19:dd:c25:c25:dd:dd:dd:ca1f
172c19:dd:c25:c25:dd:dd:dd:ca20/1272c19:dd:c25:c25:dd:dd:dd:ca21
182c19:dd:c25:c25:dd:dd:dd:ca22/1272c19:dd:c25:c25:dd:dd:dd:ca23
192c19:dd:c25:c25:dd:dd:dd:ca24/1272c19:dd:c25:c25:dd:dd:dd:ca25
202c19:dd:c25:c25:dd:dd:dd:ca26/1272c19:dd:c25:c25:dd:dd:dd:ca27
212c19:dd:c25:c25:dd:dd:dd:ca28/1272c19:dd:c25:c25:dd:dd:dd:ca29
222c19:dd:c25:c25:dd:dd:dd:ca2a/1272c19:dd:c25:c25:dd:dd:dd:ca2b
232c19:dd:c25:c25:dd:dd:dd:ca2c/1272c19:dd:c25:c25:dd:dd:dd:ca2d
242c19:dd:c25:c25:dd:dd:dd:ca2e/1272c19:dd:c25:c25:dd:dd:dd:ca2f
252c19:dd:c25:c25:dd:dd:dd:ca30/1272c19:dd:c25:c25:dd:dd:dd:ca31
262c19:dd:c25:c25:dd:dd:dd:ca32/1272c19:dd:c25:c25:dd:dd:dd:ca33
272c19:dd:c25:c25:dd:dd:dd:ca34/1272c19:dd:c25:c25:dd:dd:dd:ca35
282c19:dd:c25:c25:dd:dd:dd:ca36/1272c19:dd:c25:c25:dd:dd:dd:ca37
292c19:dd:c25:c25:dd:dd:dd:ca38/1272c19:dd:c25:c25:dd:dd:dd:ca39
302c19:dd:c25:c25:dd:dd:dd:ca3a/1272c19:dd:c25:c25:dd:dd:dd:ca3b
312c19:dd:c25:c25:dd:dd:dd:ca3c/1272c19:dd:c25:c25:dd:dd:dd:ca3d
322c19:dd:c25:c25:dd:dd:dd:ca3e/1272c19:dd:c25:c25:dd:dd:dd:ca3f
332c19:dd:c25:c25:dd:dd:dd:ca40/1272c19:dd:c25:c25:dd:dd:dd:ca41
342c19:dd:c25:c25:dd:dd:dd:ca42/1272c19:dd:c25:c25:dd:dd:dd:ca43
352c19:dd:c25:c25:dd:dd:dd:ca44/1272c19:dd:c25:c25:dd:dd:dd:ca45
362c19:dd:c25:c25:dd:dd:dd:ca46/1272c19:dd:c25:c25:dd:dd:dd:ca47
372c19:dd:c25:c25:dd:dd:dd:ca48/1272c19:dd:c25:c25:dd:dd:dd:ca49
382c19:dd:c25:c25:dd:dd:dd:ca4a/1272c19:dd:c25:c25:dd:dd:dd:ca4b
392c19:dd:c25:c25:dd:dd:dd:ca4c/1272c19:dd:c25:c25:dd:dd:dd:ca4d
402c19:dd:c25:c25:dd:dd:dd:ca4e/1272c19:dd:c25:c25:dd:dd:dd:ca4f
412c19:dd:c25:c25:dd:dd:dd:ca50/1272c19:dd:c25:c25:dd:dd:dd:ca51
422c19:dd:c25:c25:dd:dd:dd:ca52/1272c19:dd:c25:c25:dd:dd:dd:ca53
432c19:dd:c25:c25:dd:dd:dd:ca54/1272c19:dd:c25:c25:dd:dd:dd:ca55
442c19:dd:c25:c25:dd:dd:dd:ca56/1272c19:dd:c25:c25:dd:dd:dd:ca57
452c19:dd:c25:c25:dd:dd:dd:ca58/1272c19:dd:c25:c25:dd:dd:dd:ca59
462c19:dd:c25:c25:dd:dd:dd:ca5a/1272c19:dd:c25:c25:dd:dd:dd:ca5b
472c19:dd:c25:c25:dd:dd:dd:ca5c/1272c19:dd:c25:c25:dd:dd:dd:ca5d
482c19:dd:c25:c25:dd:dd:dd:ca5e/1272c19:dd:c25:c25:dd:dd:dd:ca5f
492c19:dd:c25:c25:dd:dd:dd:ca60/1272c19:dd:c25:c25:dd:dd:dd:ca61
502c19:dd:c25:c25:dd:dd:dd:ca62/1272c19:dd:c25:c25:dd:dd:dd:ca63
512c19:dd:c25:c25:dd:dd:dd:ca64/1272c19:dd:c25:c25:dd:dd:dd:ca65
522c19:dd:c25:c25:dd:dd:dd:ca66/1272c19:dd:c25:c25:dd:dd:dd:ca67
532c19:dd:c25:c25:dd:dd:dd:ca68/1272c19:dd:c25:c25:dd:dd:dd:ca69
542c19:dd:c25:c25:dd:dd:dd:ca6a/1272c19:dd:c25:c25:dd:dd:dd:ca6b
552c19:dd:c25:c25:dd:dd:dd:ca6c/1272c19:dd:c25:c25:dd:dd:dd:ca6d
562c19:dd:c25:c25:dd:dd:dd:ca6e/1272c19:dd:c25:c25:dd:dd:dd:ca6f
572c19:dd:c25:c25:dd:dd:dd:ca70/1272c19:dd:c25:c25:dd:dd:dd:ca71
582c19:dd:c25:c25:dd:dd:dd:ca72/1272c19:dd:c25:c25:dd:dd:dd:ca73
592c19:dd:c25:c25:dd:dd:dd:ca74/1272c19:dd:c25:c25:dd:dd:dd:ca75
602c19:dd:c25:c25:dd:dd:dd:ca76/1272c19:dd:c25:c25:dd:dd:dd:ca77
612c19:dd:c25:c25:dd:dd:dd:ca78/1272c19:dd:c25:c25:dd:dd:dd:ca79
622c19:dd:c25:c25:dd:dd:dd:ca7a/1272c19:dd:c25:c25:dd:dd:dd:ca7b
632c19:dd:c25:c25:dd:dd:dd:ca7c/1272c19:dd:c25:c25:dd:dd:dd:ca7d
642c19:dd:c25:c25:dd:dd:dd:ca7e/1272c19:dd:c25:c25:dd:dd:dd:ca7f
652c19:dd:c25:c25:dd:dd:dd:ca80/1272c19:dd:c25:c25:dd:dd:dd:ca81
662c19:dd:c25:c25:dd:dd:dd:ca82/1272c19:dd:c25:c25:dd:dd:dd:ca83
672c19:dd:c25:c25:dd:dd:dd:ca84/1272c19:dd:c25:c25:dd:dd:dd:ca85
682c19:dd:c25:c25:dd:dd:dd:ca86/1272c19:dd:c25:c25:dd:dd:dd:ca87
692c19:dd:c25:c25:dd:dd:dd:ca88/1272c19:dd:c25:c25:dd:dd:dd:ca89
702c19:dd:c25:c25:dd:dd:dd:ca8a/1272c19:dd:c25:c25:dd:dd:dd:ca8b
712c19:dd:c25:c25:dd:dd:dd:ca8c/1272c19:dd:c25:c25:dd:dd:dd:ca8d
722c19:dd:c25:c25:dd:dd:dd:ca8e/1272c19:dd:c25:c25:dd:dd:dd:ca8f
732c19:dd:c25:c25:dd:dd:dd:ca90/1272c19:dd:c25:c25:dd:dd:dd:ca91
742c19:dd:c25:c25:dd:dd:dd:ca92/1272c19:dd:c25:c25:dd:dd:dd:ca93
752c19:dd:c25:c25:dd:dd:dd:ca94/1272c19:dd:c25:c25:dd:dd:dd:ca95
762c19:dd:c25:c25:dd:dd:dd:ca96/1272c19:dd:c25:c25:dd:dd:dd:ca97
772c19:dd:c25:c25:dd:dd:dd:ca98/1272c19:dd:c25:c25:dd:dd:dd:ca99
782c19:dd:c25:c25:dd:dd:dd:ca9a/1272c19:dd:c25:c25:dd:dd:dd:ca9b
792c19:dd:c25:c25:dd:dd:dd:ca9c/1272c19:dd:c25:c25:dd:dd:dd:ca9d
802c19:dd:c25:c25:dd:dd:dd:ca9e/1272c19:dd:c25:c25:dd:dd:dd:ca9f
812c19:dd:c25:c25:dd:dd:dd:caa0/1272c19:dd:c25:c25:dd:dd:dd:caa1
822c19:dd:c25:c25:dd:dd:dd:caa2/1272c19:dd:c25:c25:dd:dd:dd:caa3
832c19:dd:c25:c25:dd:dd:dd:caa4/1272c19:dd:c25:c25:dd:dd:dd:caa5
842c19:dd:c25:c25:dd:dd:dd:caa6/1272c19:dd:c25:c25:dd:dd:dd:caa7
852c19:dd:c25:c25:dd:dd:dd:caa8/1272c19:dd:c25:c25:dd:dd:dd:caa9
862c19:dd:c25:c25:dd:dd:dd:caaa/1272c19:dd:c25:c25:dd:dd:dd:caab
872c19:dd:c25:c25:dd:dd:dd:caac/1272c19:dd:c25:c25:dd:dd:dd:caad
882c19:dd:c25:c25:dd:dd:dd:caae/1272c19:dd:c25:c25:dd:dd:dd:caaf
892c19:dd:c25:c25:dd:dd:dd:cab0/1272c19:dd:c25:c25:dd:dd:dd:cab1
902c19:dd:c25:c25:dd:dd:dd:cab2/1272c19:dd:c25:c25:dd:dd:dd:cab3
912c19:dd:c25:c25:dd:dd:dd:cab4/1272c19:dd:c25:c25:dd:dd:dd:cab5
922c19:dd:c25:c25:dd:dd:dd:cab6/1272c19:dd:c25:c25:dd:dd:dd:cab7
932c19:dd:c25:c25:dd:dd:dd:cab8/1272c19:dd:c25:c25:dd:dd:dd:cab9
942c19:dd:c25:c25:dd:dd:dd:caba/1272c19:dd:c25:c25:dd:dd:dd:cabb
952c19:dd:c25:c25:dd:dd:dd:cabc/1272c19:dd:c25:c25:dd:dd:dd:cabd
962c19:dd:c25:c25:dd:dd:dd:cabe/1272c19:dd:c25:c25:dd:dd:dd:cabf
972c19:dd:c25:c25:dd:dd:dd:cac0/1272c19:dd:c25:c25:dd:dd:dd:cac1
982c19:dd:c25:c25:dd:dd:dd:cac2/1272c19:dd:c25:c25:dd:dd:dd:cac3
992c19:dd:c25:c25:dd:dd:dd:cac4/1272c19:dd:c25:c25:dd:dd:dd:cac5
1002c19:dd:c25:c25:dd:dd:dd:cac6/1272c19:dd:c25:c25:dd:dd:dd:cac7
1012c19:dd:c25:c25:dd:dd:dd:cac8/1272c19:dd:c25:c25:dd:dd:dd:cac9
1022c19:dd:c25:c25:dd:dd:dd:caca/1272c19:dd:c25:c25:dd:dd:dd:cacb
1032c19:dd:c25:c25:dd:dd:dd:cacc/1272c19:dd:c25:c25:dd:dd:dd:cacd
1042c19:dd:c25:c25:dd:dd:dd:cace/1272c19:dd:c25:c25:dd:dd:dd:cacf
1052c19:dd:c25:c25:dd:dd:dd:cad0/1272c19:dd:c25:c25:dd:dd:dd:cad1
1062c19:dd:c25:c25:dd:dd:dd:cad2/1272c19:dd:c25:c25:dd:dd:dd:cad3
1072c19:dd:c25:c25:dd:dd:dd:cad4/1272c19:dd:c25:c25:dd:dd:dd:cad5
1082c19:dd:c25:c25:dd:dd:dd:cad6/1272c19:dd:c25:c25:dd:dd:dd:cad7
1092c19:dd:c25:c25:dd:dd:dd:cad8/1272c19:dd:c25:c25:dd:dd:dd:cad9
1102c19:dd:c25:c25:dd:dd:dd:cada/1272c19:dd:c25:c25:dd:dd:dd:cadb
1112c19:dd:c25:c25:dd:dd:dd:cadc/1272c19:dd:c25:c25:dd:dd:dd:cadd
1122c19:dd:c25:c25:dd:dd:dd:cade/1272c19:dd:c25:c25:dd:dd:dd:cadf
1132c19:dd:c25:c25:dd:dd:dd:cae0/1272c19:dd:c25:c25:dd:dd:dd:cae1
1142c19:dd:c25:c25:dd:dd:dd:cae2/1272c19:dd:c25:c25:dd:dd:dd:cae3
1152c19:dd:c25:c25:dd:dd:dd:cae4/1272c19:dd:c25:c25:dd:dd:dd:cae5
1162c19:dd:c25:c25:dd:dd:dd:cae6/1272c19:dd:c25:c25:dd:dd:dd:cae7
1172c19:dd:c25:c25:dd:dd:dd:cae8/1272c19:dd:c25:c25:dd:dd:dd:cae9
1182c19:dd:c25:c25:dd:dd:dd:caea/1272c19:dd:c25:c25:dd:dd:dd:caeb
1192c19:dd:c25:c25:dd:dd:dd:caec/1272c19:dd:c25:c25:dd:dd:dd:caed
1202c19:dd:c25:c25:dd:dd:dd:caee/1272c19:dd:c25:c25:dd:dd:dd:caef
1212c19:dd:c25:c25:dd:dd:dd:caf0/1272c19:dd:c25:c25:dd:dd:dd:caf1
1222c19:dd:c25:c25:dd:dd:dd:caf2/1272c19:dd:c25:c25:dd:dd:dd:caf3
1232c19:dd:c25:c25:dd:dd:dd:caf4/1272c19:dd:c25:c25:dd:dd:dd:caf5
1242c19:dd:c25:c25:dd:dd:dd:caf6/1272c19:dd:c25:c25:dd:dd:dd:caf7
1252c19:dd:c25:c25:dd:dd:dd:caf8/1272c19:dd:c25:c25:dd:dd:dd:caf9
1262c19:dd:c25:c25:dd:dd:dd:cafa/1272c19:dd:c25:c25:dd:dd:dd:cafb
1272c19:dd:c25:c25:dd:dd:dd:cafc/1272c19:dd:c25:c25:dd:dd:dd:cafd
1282c19:dd:c25:c25:dd:dd:dd:cafe/1272c19:dd:c25:c25:dd:dd:dd:caff
1292c19:dd:c25:c25:dd:dd:dd:cb00/1272c19:dd:c25:c25:dd:dd:dd:cb01
1302c19:dd:c25:c25:dd:dd:dd:cb02/1272c19:dd:c25:c25:dd:dd:dd:cb03
1312c19:dd:c25:c25:dd:dd:dd:cb04/1272c19:dd:c25:c25:dd:dd:dd:cb05
1322c19:dd:c25:c25:dd:dd:dd:cb06/1272c19:dd:c25:c25:dd:dd:dd:cb07
1332c19:dd:c25:c25:dd:dd:dd:cb08/1272c19:dd:c25:c25:dd:dd:dd:cb09
1342c19:dd:c25:c25:dd:dd:dd:cb0a/1272c19:dd:c25:c25:dd:dd:dd:cb0b
1352c19:dd:c25:c25:dd:dd:dd:cb0c/1272c19:dd:c25:c25:dd:dd:dd:cb0d
1362c19:dd:c25:c25:dd:dd:dd:cb0e/1272c19:dd:c25:c25:dd:dd:dd:cb0f
1372c19:dd:c25:c25:dd:dd:dd:cb10/1272c19:dd:c25:c25:dd:dd:dd:cb11
1382c19:dd:c25:c25:dd:dd:dd:cb12/1272c19:dd:c25:c25:dd:dd:dd:cb13
1392c19:dd:c25:c25:dd:dd:dd:cb14/1272c19:dd:c25:c25:dd:dd:dd:cb15
1402c19:dd:c25:c25:dd:dd:dd:cb16/1272c19:dd:c25:c25:dd:dd:dd:cb17
1412c19:dd:c25:c25:dd:dd:dd:cb18/1272c19:dd:c25:c25:dd:dd:dd:cb19
1422c19:dd:c25:c25:dd:dd:dd:cb1a/1272c19:dd:c25:c25:dd:dd:dd:cb1b
1432c19:dd:c25:c25:dd:dd:dd:cb1c/1272c19:dd:c25:c25:dd:dd:dd:cb1d
1442c19:dd:c25:c25:dd:dd:dd:cb1e/1272c19:dd:c25:c25:dd:dd:dd:cb1f
1452c19:dd:c25:c25:dd:dd:dd:cb20/1272c19:dd:c25:c25:dd:dd:dd:cb21
1462c19:dd:c25:c25:dd:dd:dd:cb22/1272c19:dd:c25:c25:dd:dd:dd:cb23
1472c19:dd:c25:c25:dd:dd:dd:cb24/1272c19:dd:c25:c25:dd:dd:dd:cb25
1482c19:dd:c25:c25:dd:dd:dd:cb26/1272c19:dd:c25:c25:dd:dd:dd:cb27
1492c19:dd:c25:c25:dd:dd:dd:cb28/1272c19:dd:c25:c25:dd:dd:dd:cb29
1502c19:dd:c25:c25:dd:dd:dd:cb2a/1272c19:dd:c25:c25:dd:dd:dd:cb2b
1512c19:dd:c25:c25:dd:dd:dd:cb2c/1272c19:dd:c25:c25:dd:dd:dd:cb2d
1522c19:dd:c25:c25:dd:dd:dd:cb2e/1272c19:dd:c25:c25:dd:dd:dd:cb2f
1532c19:dd:c25:c25:dd:dd:dd:cb30/1272c19:dd:c25:c25:dd:dd:dd:cb31
1542c19:dd:c25:c25:dd:dd:dd:cb32/1272c19:dd:c25:c25:dd:dd:dd:cb33
1552c19:dd:c25:c25:dd:dd:dd:cb34/1272c19:dd:c25:c25:dd:dd:dd:cb35
1562c19:dd:c25:c25:dd:dd:dd:cb36/1272c19:dd:c25:c25:dd:dd:dd:cb37
1572c19:dd:c25:c25:dd:dd:dd:cb38/1272c19:dd:c25:c25:dd:dd:dd:cb39
1582c19:dd:c25:c25:dd:dd:dd:cb3a/1272c19:dd:c25:c25:dd:dd:dd:cb3b
1592c19:dd:c25:c25:dd:dd:dd:cb3c/1272c19:dd:c25:c25:dd:dd:dd:cb3d
1602c19:dd:c25:c25:dd:dd:dd:cb3e/1272c19:dd:c25:c25:dd:dd:dd:cb3f
1612c19:dd:c25:c25:dd:dd:dd:cb40/1272c19:dd:c25:c25:dd:dd:dd:cb41
1622c19:dd:c25:c25:dd:dd:dd:cb42/1272c19:dd:c25:c25:dd:dd:dd:cb43
1632c19:dd:c25:c25:dd:dd:dd:cb44/1272c19:dd:c25:c25:dd:dd:dd:cb45
1642c19:dd:c25:c25:dd:dd:dd:cb46/1272c19:dd:c25:c25:dd:dd:dd:cb47
1652c19:dd:c25:c25:dd:dd:dd:cb48/1272c19:dd:c25:c25:dd:dd:dd:cb49
1662c19:dd:c25:c25:dd:dd:dd:cb4a/1272c19:dd:c25:c25:dd:dd:dd:cb4b
1672c19:dd:c25:c25:dd:dd:dd:cb4c/1272c19:dd:c25:c25:dd:dd:dd:cb4d
1682c19:dd:c25:c25:dd:dd:dd:cb4e/1272c19:dd:c25:c25:dd:dd:dd:cb4f
1692c19:dd:c25:c25:dd:dd:dd:cb50/1272c19:dd:c25:c25:dd:dd:dd:cb51
1702c19:dd:c25:c25:dd:dd:dd:cb52/1272c19:dd:c25:c25:dd:dd:dd:cb53
1712c19:dd:c25:c25:dd:dd:dd:cb54/1272c19:dd:c25:c25:dd:dd:dd:cb55
1722c19:dd:c25:c25:dd:dd:dd:cb56/1272c19:dd:c25:c25:dd:dd:dd:cb57
1732c19:dd:c25:c25:dd:dd:dd:cb58/1272c19:dd:c25:c25:dd:dd:dd:cb59
1742c19:dd:c25:c25:dd:dd:dd:cb5a/1272c19:dd:c25:c25:dd:dd:dd:cb5b
1752c19:dd:c25:c25:dd:dd:dd:cb5c/1272c19:dd:c25:c25:dd:dd:dd:cb5d
1762c19:dd:c25:c25:dd:dd:dd:cb5e/1272c19:dd:c25:c25:dd:dd:dd:cb5f
1772c19:dd:c25:c25:dd:dd:dd:cb60/1272c19:dd:c25:c25:dd:dd:dd:cb61
1782c19:dd:c25:c25:dd:dd:dd:cb62/1272c19:dd:c25:c25:dd:dd:dd:cb63
1792c19:dd:c25:c25:dd:dd:dd:cb64/1272c19:dd:c25:c25:dd:dd:dd:cb65
1802c19:dd:c25:c25:dd:dd:dd:cb66/1272c19:dd:c25:c25:dd:dd:dd:cb67
1812c19:dd:c25:c25:dd:dd:dd:cb68/1272c19:dd:c25:c25:dd:dd:dd:cb69
1822c19:dd:c25:c25:dd:dd:dd:cb6a/1272c19:dd:c25:c25:dd:dd:dd:cb6b
1832c19:dd:c25:c25:dd:dd:dd:cb6c/1272c19:dd:c25:c25:dd:dd:dd:cb6d
1842c19:dd:c25:c25:dd:dd:dd:cb6e/1272c19:dd:c25:c25:dd:dd:dd:cb6f
1852c19:dd:c25:c25:dd:dd:dd:cb70/1272c19:dd:c25:c25:dd:dd:dd:cb71
1862c19:dd:c25:c25:dd:dd:dd:cb72/1272c19:dd:c25:c25:dd:dd:dd:cb73
1872c19:dd:c25:c25:dd:dd:dd:cb74/1272c19:dd:c25:c25:dd:dd:dd:cb75
1882c19:dd:c25:c25:dd:dd:dd:cb76/1272c19:dd:c25:c25:dd:dd:dd:cb77
1892c19:dd:c25:c25:dd:dd:dd:cb78/1272c19:dd:c25:c25:dd:dd:dd:cb79
1902c19:dd:c25:c25:dd:dd:dd:cb7a/1272c19:dd:c25:c25:dd:dd:dd:cb7b
1912c19:dd:c25:c25:dd:dd:dd:cb7c/1272c19:dd:c25:c25:dd:dd:dd:cb7d
1922c19:dd:c25:c25:dd:dd:dd:cb7e/1272c19:dd:c25:c25:dd:dd:dd:cb7f
1932c19:dd:c25:c25:dd:dd:dd:cb80/1272c19:dd:c25:c25:dd:dd:dd:cb81
1942c19:dd:c25:c25:dd:dd:dd:cb82/1272c19:dd:c25:c25:dd:dd:dd:cb83
1952c19:dd:c25:c25:dd:dd:dd:cb84/1272c19:dd:c25:c25:dd:dd:dd:cb85
1962c19:dd:c25:c25:dd:dd:dd:cb86/1272c19:dd:c25:c25:dd:dd:dd:cb87
1972c19:dd:c25:c25:dd:dd:dd:cb88/1272c19:dd:c25:c25:dd:dd:dd:cb89
1982c19:dd:c25:c25:dd:dd:dd:cb8a/1272c19:dd:c25:c25:dd:dd:dd:cb8b
1992c19:dd:c25:c25:dd:dd:dd:cb8c/1272c19:dd:c25:c25:dd:dd:dd:cb8d
2002c19:dd:c25:c25:dd:dd:dd:cb8e/1272c19:dd:c25:c25:dd:dd:dd:cb8f
2012c19:dd:c25:c25:dd:dd:dd:cb90/1272c19:dd:c25:c25:dd:dd:dd:cb91
2022c19:dd:c25:c25:dd:dd:dd:cb92/1272c19:dd:c25:c25:dd:dd:dd:cb93
2032c19:dd:c25:c25:dd:dd:dd:cb94/1272c19:dd:c25:c25:dd:dd:dd:cb95
2042c19:dd:c25:c25:dd:dd:dd:cb96/1272c19:dd:c25:c25:dd:dd:dd:cb97
2052c19:dd:c25:c25:dd:dd:dd:cb98/1272c19:dd:c25:c25:dd:dd:dd:cb99
2062c19:dd:c25:c25:dd:dd:dd:cb9a/1272c19:dd:c25:c25:dd:dd:dd:cb9b
2072c19:dd:c25:c25:dd:dd:dd:cb9c/1272c19:dd:c25:c25:dd:dd:dd:cb9d
2082c19:dd:c25:c25:dd:dd:dd:cb9e/1272c19:dd:c25:c25:dd:dd:dd:cb9f
2092c19:dd:c25:c25:dd:dd:dd:cba0/1272c19:dd:c25:c25:dd:dd:dd:cba1
2102c19:dd:c25:c25:dd:dd:dd:cba2/1272c19:dd:c25:c25:dd:dd:dd:cba3
2112c19:dd:c25:c25:dd:dd:dd:cba4/1272c19:dd:c25:c25:dd:dd:dd:cba5
2122c19:dd:c25:c25:dd:dd:dd:cba6/1272c19:dd:c25:c25:dd:dd:dd:cba7
2132c19:dd:c25:c25:dd:dd:dd:cba8/1272c19:dd:c25:c25:dd:dd:dd:cba9
2142c19:dd:c25:c25:dd:dd:dd:cbaa/1272c19:dd:c25:c25:dd:dd:dd:cbab
2152c19:dd:c25:c25:dd:dd:dd:cbac/1272c19:dd:c25:c25:dd:dd:dd:cbad
2162c19:dd:c25:c25:dd:dd:dd:cbae/1272c19:dd:c25:c25:dd:dd:dd:cbaf
2172c19:dd:c25:c25:dd:dd:dd:cbb0/1272c19:dd:c25:c25:dd:dd:dd:cbb1
2182c19:dd:c25:c25:dd:dd:dd:cbb2/1272c19:dd:c25:c25:dd:dd:dd:cbb3
2192c19:dd:c25:c25:dd:dd:dd:cbb4/1272c19:dd:c25:c25:dd:dd:dd:cbb5
2202c19:dd:c25:c25:dd:dd:dd:cbb6/1272c19:dd:c25:c25:dd:dd:dd:cbb7
2212c19:dd:c25:c25:dd:dd:dd:cbb8/1272c19:dd:c25:c25:dd:dd:dd:cbb9
2222c19:dd:c25:c25:dd:dd:dd:cbba/1272c19:dd:c25:c25:dd:dd:dd:cbbb
2232c19:dd:c25:c25:dd:dd:dd:cbbc/1272c19:dd:c25:c25:dd:dd:dd:cbbd
2242c19:dd:c25:c25:dd:dd:dd:cbbe/1272c19:dd:c25:c25:dd:dd:dd:cbbf
2252c19:dd:c25:c25:dd:dd:dd:cbc0/1272c19:dd:c25:c25:dd:dd:dd:cbc1
2262c19:dd:c25:c25:dd:dd:dd:cbc2/1272c19:dd:c25:c25:dd:dd:dd:cbc3
2272c19:dd:c25:c25:dd:dd:dd:cbc4/1272c19:dd:c25:c25:dd:dd:dd:cbc5
2282c19:dd:c25:c25:dd:dd:dd:cbc6/1272c19:dd:c25:c25:dd:dd:dd:cbc7
2292c19:dd:c25:c25:dd:dd:dd:cbc8/1272c19:dd:c25:c25:dd:dd:dd:cbc9
2302c19:dd:c25:c25:dd:dd:dd:cbca/1272c19:dd:c25:c25:dd:dd:dd:cbcb
2312c19:dd:c25:c25:dd:dd:dd:cbcc/1272c19:dd:c25:c25:dd:dd:dd:cbcd
2322c19:dd:c25:c25:dd:dd:dd:cbce/1272c19:dd:c25:c25:dd:dd:dd:cbcf
2332c19:dd:c25:c25:dd:dd:dd:cbd0/1272c19:dd:c25:c25:dd:dd:dd:cbd1
2342c19:dd:c25:c25:dd:dd:dd:cbd2/1272c19:dd:c25:c25:dd:dd:dd:cbd3
2352c19:dd:c25:c25:dd:dd:dd:cbd4/1272c19:dd:c25:c25:dd:dd:dd:cbd5
2362c19:dd:c25:c25:dd:dd:dd:cbd6/1272c19:dd:c25:c25:dd:dd:dd:cbd7
2372c19:dd:c25:c25:dd:dd:dd:cbd8/1272c19:dd:c25:c25:dd:dd:dd:cbd9
2382c19:dd:c25:c25:dd:dd:dd:cbda/1272c19:dd:c25:c25:dd:dd:dd:cbdb
2392c19:dd:c25:c25:dd:dd:dd:cbdc/1272c19:dd:c25:c25:dd:dd:dd:cbdd
2402c19:dd:c25:c25:dd:dd:dd:cbde/1272c19:dd:c25:c25:dd:dd:dd:cbdf
2412c19:dd:c25:c25:dd:dd:dd:cbe0/1272c19:dd:c25:c25:dd:dd:dd:cbe1
2422c19:dd:c25:c25:dd:dd:dd:cbe2/1272c19:dd:c25:c25:dd:dd:dd:cbe3
2432c19:dd:c25:c25:dd:dd:dd:cbe4/1272c19:dd:c25:c25:dd:dd:dd:cbe5
2442c19:dd:c25:c25:dd:dd:dd:cbe6/1272c19:dd:c25:c25:dd:dd:dd:cbe7
2452c19:dd:c25:c25:dd:dd:dd:cbe8/1272c19:dd:c25:c25:dd:dd:dd:cbe9
2462c19:dd:c25:c25:dd:dd:dd:cbea/1272c19:dd:c25:c25:dd:dd:dd:cbeb
2472c19:dd:c25:c25:dd:dd:dd:cbec/1272c19:dd:c25:c25:dd:dd:dd:cbed
2482c19:dd:c25:c25:dd:dd:dd:cbee/1272c19:dd:c25:c25:dd:dd:dd:cbef
2492c19:dd:c25:c25:dd:dd:dd:cbf0/1272c19:dd:c25:c25:dd:dd:dd:cbf1
2502c19:dd:c25:c25:dd:dd:dd:cbf2/1272c19:dd:c25:c25:dd:dd:dd:cbf3
2512c19:dd:c25:c25:dd:dd:dd:cbf4/1272c19:dd:c25:c25:dd:dd:dd:cbf5
2522c19:dd:c25:c25:dd:dd:dd:cbf6/1272c19:dd:c25:c25:dd:dd:dd:cbf7
2532c19:dd:c25:c25:dd:dd:dd:cbf8/1272c19:dd:c25:c25:dd:dd:dd:cbf9
2542c19:dd:c25:c25:dd:dd:dd:cbfa/1272c19:dd:c25:c25:dd:dd:dd:cbfb
2552c19:dd:c25:c25:dd:dd:dd:cbfc/1272c19:dd:c25:c25:dd:dd:dd:cbfd
2562c19:dd:c25:c25:dd:dd:dd:cbfe/1272c19:dd:c25:c25:dd:dd:dd:cbff

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.