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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:c25d:dd:dd:dd:cc00/119
First address
2c19:dd:c25:c25d:dd:dd:dd:cc00
Last address
2c19:dd:c25:c25d:dd:dd:dd:cdff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:cc00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
c.c.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.c.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
/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:c25d:dd:dd:dd:cc00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:cc00/1272c19:dd:c25:c25d:dd:dd:dd:cc01
22c19:dd:c25:c25d:dd:dd:dd:cc02/1272c19:dd:c25:c25d:dd:dd:dd:cc03
32c19:dd:c25:c25d:dd:dd:dd:cc04/1272c19:dd:c25:c25d:dd:dd:dd:cc05
42c19:dd:c25:c25d:dd:dd:dd:cc06/1272c19:dd:c25:c25d:dd:dd:dd:cc07
52c19:dd:c25:c25d:dd:dd:dd:cc08/1272c19:dd:c25:c25d:dd:dd:dd:cc09
62c19:dd:c25:c25d:dd:dd:dd:cc0a/1272c19:dd:c25:c25d:dd:dd:dd:cc0b
72c19:dd:c25:c25d:dd:dd:dd:cc0c/1272c19:dd:c25:c25d:dd:dd:dd:cc0d
82c19:dd:c25:c25d:dd:dd:dd:cc0e/1272c19:dd:c25:c25d:dd:dd:dd:cc0f
92c19:dd:c25:c25d:dd:dd:dd:cc10/1272c19:dd:c25:c25d:dd:dd:dd:cc11
102c19:dd:c25:c25d:dd:dd:dd:cc12/1272c19:dd:c25:c25d:dd:dd:dd:cc13
112c19:dd:c25:c25d:dd:dd:dd:cc14/1272c19:dd:c25:c25d:dd:dd:dd:cc15
122c19:dd:c25:c25d:dd:dd:dd:cc16/1272c19:dd:c25:c25d:dd:dd:dd:cc17
132c19:dd:c25:c25d:dd:dd:dd:cc18/1272c19:dd:c25:c25d:dd:dd:dd:cc19
142c19:dd:c25:c25d:dd:dd:dd:cc1a/1272c19:dd:c25:c25d:dd:dd:dd:cc1b
152c19:dd:c25:c25d:dd:dd:dd:cc1c/1272c19:dd:c25:c25d:dd:dd:dd:cc1d
162c19:dd:c25:c25d:dd:dd:dd:cc1e/1272c19:dd:c25:c25d:dd:dd:dd:cc1f
172c19:dd:c25:c25d:dd:dd:dd:cc20/1272c19:dd:c25:c25d:dd:dd:dd:cc21
182c19:dd:c25:c25d:dd:dd:dd:cc22/1272c19:dd:c25:c25d:dd:dd:dd:cc23
192c19:dd:c25:c25d:dd:dd:dd:cc24/1272c19:dd:c25:c25d:dd:dd:dd:cc25
202c19:dd:c25:c25d:dd:dd:dd:cc26/1272c19:dd:c25:c25d:dd:dd:dd:cc27
212c19:dd:c25:c25d:dd:dd:dd:cc28/1272c19:dd:c25:c25d:dd:dd:dd:cc29
222c19:dd:c25:c25d:dd:dd:dd:cc2a/1272c19:dd:c25:c25d:dd:dd:dd:cc2b
232c19:dd:c25:c25d:dd:dd:dd:cc2c/1272c19:dd:c25:c25d:dd:dd:dd:cc2d
242c19:dd:c25:c25d:dd:dd:dd:cc2e/1272c19:dd:c25:c25d:dd:dd:dd:cc2f
252c19:dd:c25:c25d:dd:dd:dd:cc30/1272c19:dd:c25:c25d:dd:dd:dd:cc31
262c19:dd:c25:c25d:dd:dd:dd:cc32/1272c19:dd:c25:c25d:dd:dd:dd:cc33
272c19:dd:c25:c25d:dd:dd:dd:cc34/1272c19:dd:c25:c25d:dd:dd:dd:cc35
282c19:dd:c25:c25d:dd:dd:dd:cc36/1272c19:dd:c25:c25d:dd:dd:dd:cc37
292c19:dd:c25:c25d:dd:dd:dd:cc38/1272c19:dd:c25:c25d:dd:dd:dd:cc39
302c19:dd:c25:c25d:dd:dd:dd:cc3a/1272c19:dd:c25:c25d:dd:dd:dd:cc3b
312c19:dd:c25:c25d:dd:dd:dd:cc3c/1272c19:dd:c25:c25d:dd:dd:dd:cc3d
322c19:dd:c25:c25d:dd:dd:dd:cc3e/1272c19:dd:c25:c25d:dd:dd:dd:cc3f
332c19:dd:c25:c25d:dd:dd:dd:cc40/1272c19:dd:c25:c25d:dd:dd:dd:cc41
342c19:dd:c25:c25d:dd:dd:dd:cc42/1272c19:dd:c25:c25d:dd:dd:dd:cc43
352c19:dd:c25:c25d:dd:dd:dd:cc44/1272c19:dd:c25:c25d:dd:dd:dd:cc45
362c19:dd:c25:c25d:dd:dd:dd:cc46/1272c19:dd:c25:c25d:dd:dd:dd:cc47
372c19:dd:c25:c25d:dd:dd:dd:cc48/1272c19:dd:c25:c25d:dd:dd:dd:cc49
382c19:dd:c25:c25d:dd:dd:dd:cc4a/1272c19:dd:c25:c25d:dd:dd:dd:cc4b
392c19:dd:c25:c25d:dd:dd:dd:cc4c/1272c19:dd:c25:c25d:dd:dd:dd:cc4d
402c19:dd:c25:c25d:dd:dd:dd:cc4e/1272c19:dd:c25:c25d:dd:dd:dd:cc4f
412c19:dd:c25:c25d:dd:dd:dd:cc50/1272c19:dd:c25:c25d:dd:dd:dd:cc51
422c19:dd:c25:c25d:dd:dd:dd:cc52/1272c19:dd:c25:c25d:dd:dd:dd:cc53
432c19:dd:c25:c25d:dd:dd:dd:cc54/1272c19:dd:c25:c25d:dd:dd:dd:cc55
442c19:dd:c25:c25d:dd:dd:dd:cc56/1272c19:dd:c25:c25d:dd:dd:dd:cc57
452c19:dd:c25:c25d:dd:dd:dd:cc58/1272c19:dd:c25:c25d:dd:dd:dd:cc59
462c19:dd:c25:c25d:dd:dd:dd:cc5a/1272c19:dd:c25:c25d:dd:dd:dd:cc5b
472c19:dd:c25:c25d:dd:dd:dd:cc5c/1272c19:dd:c25:c25d:dd:dd:dd:cc5d
482c19:dd:c25:c25d:dd:dd:dd:cc5e/1272c19:dd:c25:c25d:dd:dd:dd:cc5f
492c19:dd:c25:c25d:dd:dd:dd:cc60/1272c19:dd:c25:c25d:dd:dd:dd:cc61
502c19:dd:c25:c25d:dd:dd:dd:cc62/1272c19:dd:c25:c25d:dd:dd:dd:cc63
512c19:dd:c25:c25d:dd:dd:dd:cc64/1272c19:dd:c25:c25d:dd:dd:dd:cc65
522c19:dd:c25:c25d:dd:dd:dd:cc66/1272c19:dd:c25:c25d:dd:dd:dd:cc67
532c19:dd:c25:c25d:dd:dd:dd:cc68/1272c19:dd:c25:c25d:dd:dd:dd:cc69
542c19:dd:c25:c25d:dd:dd:dd:cc6a/1272c19:dd:c25:c25d:dd:dd:dd:cc6b
552c19:dd:c25:c25d:dd:dd:dd:cc6c/1272c19:dd:c25:c25d:dd:dd:dd:cc6d
562c19:dd:c25:c25d:dd:dd:dd:cc6e/1272c19:dd:c25:c25d:dd:dd:dd:cc6f
572c19:dd:c25:c25d:dd:dd:dd:cc70/1272c19:dd:c25:c25d:dd:dd:dd:cc71
582c19:dd:c25:c25d:dd:dd:dd:cc72/1272c19:dd:c25:c25d:dd:dd:dd:cc73
592c19:dd:c25:c25d:dd:dd:dd:cc74/1272c19:dd:c25:c25d:dd:dd:dd:cc75
602c19:dd:c25:c25d:dd:dd:dd:cc76/1272c19:dd:c25:c25d:dd:dd:dd:cc77
612c19:dd:c25:c25d:dd:dd:dd:cc78/1272c19:dd:c25:c25d:dd:dd:dd:cc79
622c19:dd:c25:c25d:dd:dd:dd:cc7a/1272c19:dd:c25:c25d:dd:dd:dd:cc7b
632c19:dd:c25:c25d:dd:dd:dd:cc7c/1272c19:dd:c25:c25d:dd:dd:dd:cc7d
642c19:dd:c25:c25d:dd:dd:dd:cc7e/1272c19:dd:c25:c25d:dd:dd:dd:cc7f
652c19:dd:c25:c25d:dd:dd:dd:cc80/1272c19:dd:c25:c25d:dd:dd:dd:cc81
662c19:dd:c25:c25d:dd:dd:dd:cc82/1272c19:dd:c25:c25d:dd:dd:dd:cc83
672c19:dd:c25:c25d:dd:dd:dd:cc84/1272c19:dd:c25:c25d:dd:dd:dd:cc85
682c19:dd:c25:c25d:dd:dd:dd:cc86/1272c19:dd:c25:c25d:dd:dd:dd:cc87
692c19:dd:c25:c25d:dd:dd:dd:cc88/1272c19:dd:c25:c25d:dd:dd:dd:cc89
702c19:dd:c25:c25d:dd:dd:dd:cc8a/1272c19:dd:c25:c25d:dd:dd:dd:cc8b
712c19:dd:c25:c25d:dd:dd:dd:cc8c/1272c19:dd:c25:c25d:dd:dd:dd:cc8d
722c19:dd:c25:c25d:dd:dd:dd:cc8e/1272c19:dd:c25:c25d:dd:dd:dd:cc8f
732c19:dd:c25:c25d:dd:dd:dd:cc90/1272c19:dd:c25:c25d:dd:dd:dd:cc91
742c19:dd:c25:c25d:dd:dd:dd:cc92/1272c19:dd:c25:c25d:dd:dd:dd:cc93
752c19:dd:c25:c25d:dd:dd:dd:cc94/1272c19:dd:c25:c25d:dd:dd:dd:cc95
762c19:dd:c25:c25d:dd:dd:dd:cc96/1272c19:dd:c25:c25d:dd:dd:dd:cc97
772c19:dd:c25:c25d:dd:dd:dd:cc98/1272c19:dd:c25:c25d:dd:dd:dd:cc99
782c19:dd:c25:c25d:dd:dd:dd:cc9a/1272c19:dd:c25:c25d:dd:dd:dd:cc9b
792c19:dd:c25:c25d:dd:dd:dd:cc9c/1272c19:dd:c25:c25d:dd:dd:dd:cc9d
802c19:dd:c25:c25d:dd:dd:dd:cc9e/1272c19:dd:c25:c25d:dd:dd:dd:cc9f
812c19:dd:c25:c25d:dd:dd:dd:cca0/1272c19:dd:c25:c25d:dd:dd:dd:cca1
822c19:dd:c25:c25d:dd:dd:dd:cca2/1272c19:dd:c25:c25d:dd:dd:dd:cca3
832c19:dd:c25:c25d:dd:dd:dd:cca4/1272c19:dd:c25:c25d:dd:dd:dd:cca5
842c19:dd:c25:c25d:dd:dd:dd:cca6/1272c19:dd:c25:c25d:dd:dd:dd:cca7
852c19:dd:c25:c25d:dd:dd:dd:cca8/1272c19:dd:c25:c25d:dd:dd:dd:cca9
862c19:dd:c25:c25d:dd:dd:dd:ccaa/1272c19:dd:c25:c25d:dd:dd:dd:ccab
872c19:dd:c25:c25d:dd:dd:dd:ccac/1272c19:dd:c25:c25d:dd:dd:dd:ccad
882c19:dd:c25:c25d:dd:dd:dd:ccae/1272c19:dd:c25:c25d:dd:dd:dd:ccaf
892c19:dd:c25:c25d:dd:dd:dd:ccb0/1272c19:dd:c25:c25d:dd:dd:dd:ccb1
902c19:dd:c25:c25d:dd:dd:dd:ccb2/1272c19:dd:c25:c25d:dd:dd:dd:ccb3
912c19:dd:c25:c25d:dd:dd:dd:ccb4/1272c19:dd:c25:c25d:dd:dd:dd:ccb5
922c19:dd:c25:c25d:dd:dd:dd:ccb6/1272c19:dd:c25:c25d:dd:dd:dd:ccb7
932c19:dd:c25:c25d:dd:dd:dd:ccb8/1272c19:dd:c25:c25d:dd:dd:dd:ccb9
942c19:dd:c25:c25d:dd:dd:dd:ccba/1272c19:dd:c25:c25d:dd:dd:dd:ccbb
952c19:dd:c25:c25d:dd:dd:dd:ccbc/1272c19:dd:c25:c25d:dd:dd:dd:ccbd
962c19:dd:c25:c25d:dd:dd:dd:ccbe/1272c19:dd:c25:c25d:dd:dd:dd:ccbf
972c19:dd:c25:c25d:dd:dd:dd:ccc0/1272c19:dd:c25:c25d:dd:dd:dd:ccc1
982c19:dd:c25:c25d:dd:dd:dd:ccc2/1272c19:dd:c25:c25d:dd:dd:dd:ccc3
992c19:dd:c25:c25d:dd:dd:dd:ccc4/1272c19:dd:c25:c25d:dd:dd:dd:ccc5
1002c19:dd:c25:c25d:dd:dd:dd:ccc6/1272c19:dd:c25:c25d:dd:dd:dd:ccc7
1012c19:dd:c25:c25d:dd:dd:dd:ccc8/1272c19:dd:c25:c25d:dd:dd:dd:ccc9
1022c19:dd:c25:c25d:dd:dd:dd:ccca/1272c19:dd:c25:c25d:dd:dd:dd:cccb
1032c19:dd:c25:c25d:dd:dd:dd:cccc/1272c19:dd:c25:c25d:dd:dd:dd:cccd
1042c19:dd:c25:c25d:dd:dd:dd:ccce/1272c19:dd:c25:c25d:dd:dd:dd:cccf
1052c19:dd:c25:c25d:dd:dd:dd:ccd0/1272c19:dd:c25:c25d:dd:dd:dd:ccd1
1062c19:dd:c25:c25d:dd:dd:dd:ccd2/1272c19:dd:c25:c25d:dd:dd:dd:ccd3
1072c19:dd:c25:c25d:dd:dd:dd:ccd4/1272c19:dd:c25:c25d:dd:dd:dd:ccd5
1082c19:dd:c25:c25d:dd:dd:dd:ccd6/1272c19:dd:c25:c25d:dd:dd:dd:ccd7
1092c19:dd:c25:c25d:dd:dd:dd:ccd8/1272c19:dd:c25:c25d:dd:dd:dd:ccd9
1102c19:dd:c25:c25d:dd:dd:dd:ccda/1272c19:dd:c25:c25d:dd:dd:dd:ccdb
1112c19:dd:c25:c25d:dd:dd:dd:ccdc/1272c19:dd:c25:c25d:dd:dd:dd:ccdd
1122c19:dd:c25:c25d:dd:dd:dd:ccde/1272c19:dd:c25:c25d:dd:dd:dd:ccdf
1132c19:dd:c25:c25d:dd:dd:dd:cce0/1272c19:dd:c25:c25d:dd:dd:dd:cce1
1142c19:dd:c25:c25d:dd:dd:dd:cce2/1272c19:dd:c25:c25d:dd:dd:dd:cce3
1152c19:dd:c25:c25d:dd:dd:dd:cce4/1272c19:dd:c25:c25d:dd:dd:dd:cce5
1162c19:dd:c25:c25d:dd:dd:dd:cce6/1272c19:dd:c25:c25d:dd:dd:dd:cce7
1172c19:dd:c25:c25d:dd:dd:dd:cce8/1272c19:dd:c25:c25d:dd:dd:dd:cce9
1182c19:dd:c25:c25d:dd:dd:dd:ccea/1272c19:dd:c25:c25d:dd:dd:dd:cceb
1192c19:dd:c25:c25d:dd:dd:dd:ccec/1272c19:dd:c25:c25d:dd:dd:dd:cced
1202c19:dd:c25:c25d:dd:dd:dd:ccee/1272c19:dd:c25:c25d:dd:dd:dd:ccef
1212c19:dd:c25:c25d:dd:dd:dd:ccf0/1272c19:dd:c25:c25d:dd:dd:dd:ccf1
1222c19:dd:c25:c25d:dd:dd:dd:ccf2/1272c19:dd:c25:c25d:dd:dd:dd:ccf3
1232c19:dd:c25:c25d:dd:dd:dd:ccf4/1272c19:dd:c25:c25d:dd:dd:dd:ccf5
1242c19:dd:c25:c25d:dd:dd:dd:ccf6/1272c19:dd:c25:c25d:dd:dd:dd:ccf7
1252c19:dd:c25:c25d:dd:dd:dd:ccf8/1272c19:dd:c25:c25d:dd:dd:dd:ccf9
1262c19:dd:c25:c25d:dd:dd:dd:ccfa/1272c19:dd:c25:c25d:dd:dd:dd:ccfb
1272c19:dd:c25:c25d:dd:dd:dd:ccfc/1272c19:dd:c25:c25d:dd:dd:dd:ccfd
1282c19:dd:c25:c25d:dd:dd:dd:ccfe/1272c19:dd:c25:c25d:dd:dd:dd:ccff
1292c19:dd:c25:c25d:dd:dd:dd:cd00/1272c19:dd:c25:c25d:dd:dd:dd:cd01
1302c19:dd:c25:c25d:dd:dd:dd:cd02/1272c19:dd:c25:c25d:dd:dd:dd:cd03
1312c19:dd:c25:c25d:dd:dd:dd:cd04/1272c19:dd:c25:c25d:dd:dd:dd:cd05
1322c19:dd:c25:c25d:dd:dd:dd:cd06/1272c19:dd:c25:c25d:dd:dd:dd:cd07
1332c19:dd:c25:c25d:dd:dd:dd:cd08/1272c19:dd:c25:c25d:dd:dd:dd:cd09
1342c19:dd:c25:c25d:dd:dd:dd:cd0a/1272c19:dd:c25:c25d:dd:dd:dd:cd0b
1352c19:dd:c25:c25d:dd:dd:dd:cd0c/1272c19:dd:c25:c25d:dd:dd:dd:cd0d
1362c19:dd:c25:c25d:dd:dd:dd:cd0e/1272c19:dd:c25:c25d:dd:dd:dd:cd0f
1372c19:dd:c25:c25d:dd:dd:dd:cd10/1272c19:dd:c25:c25d:dd:dd:dd:cd11
1382c19:dd:c25:c25d:dd:dd:dd:cd12/1272c19:dd:c25:c25d:dd:dd:dd:cd13
1392c19:dd:c25:c25d:dd:dd:dd:cd14/1272c19:dd:c25:c25d:dd:dd:dd:cd15
1402c19:dd:c25:c25d:dd:dd:dd:cd16/1272c19:dd:c25:c25d:dd:dd:dd:cd17
1412c19:dd:c25:c25d:dd:dd:dd:cd18/1272c19:dd:c25:c25d:dd:dd:dd:cd19
1422c19:dd:c25:c25d:dd:dd:dd:cd1a/1272c19:dd:c25:c25d:dd:dd:dd:cd1b
1432c19:dd:c25:c25d:dd:dd:dd:cd1c/1272c19:dd:c25:c25d:dd:dd:dd:cd1d
1442c19:dd:c25:c25d:dd:dd:dd:cd1e/1272c19:dd:c25:c25d:dd:dd:dd:cd1f
1452c19:dd:c25:c25d:dd:dd:dd:cd20/1272c19:dd:c25:c25d:dd:dd:dd:cd21
1462c19:dd:c25:c25d:dd:dd:dd:cd22/1272c19:dd:c25:c25d:dd:dd:dd:cd23
1472c19:dd:c25:c25d:dd:dd:dd:cd24/1272c19:dd:c25:c25d:dd:dd:dd:cd25
1482c19:dd:c25:c25d:dd:dd:dd:cd26/1272c19:dd:c25:c25d:dd:dd:dd:cd27
1492c19:dd:c25:c25d:dd:dd:dd:cd28/1272c19:dd:c25:c25d:dd:dd:dd:cd29
1502c19:dd:c25:c25d:dd:dd:dd:cd2a/1272c19:dd:c25:c25d:dd:dd:dd:cd2b
1512c19:dd:c25:c25d:dd:dd:dd:cd2c/1272c19:dd:c25:c25d:dd:dd:dd:cd2d
1522c19:dd:c25:c25d:dd:dd:dd:cd2e/1272c19:dd:c25:c25d:dd:dd:dd:cd2f
1532c19:dd:c25:c25d:dd:dd:dd:cd30/1272c19:dd:c25:c25d:dd:dd:dd:cd31
1542c19:dd:c25:c25d:dd:dd:dd:cd32/1272c19:dd:c25:c25d:dd:dd:dd:cd33
1552c19:dd:c25:c25d:dd:dd:dd:cd34/1272c19:dd:c25:c25d:dd:dd:dd:cd35
1562c19:dd:c25:c25d:dd:dd:dd:cd36/1272c19:dd:c25:c25d:dd:dd:dd:cd37
1572c19:dd:c25:c25d:dd:dd:dd:cd38/1272c19:dd:c25:c25d:dd:dd:dd:cd39
1582c19:dd:c25:c25d:dd:dd:dd:cd3a/1272c19:dd:c25:c25d:dd:dd:dd:cd3b
1592c19:dd:c25:c25d:dd:dd:dd:cd3c/1272c19:dd:c25:c25d:dd:dd:dd:cd3d
1602c19:dd:c25:c25d:dd:dd:dd:cd3e/1272c19:dd:c25:c25d:dd:dd:dd:cd3f
1612c19:dd:c25:c25d:dd:dd:dd:cd40/1272c19:dd:c25:c25d:dd:dd:dd:cd41
1622c19:dd:c25:c25d:dd:dd:dd:cd42/1272c19:dd:c25:c25d:dd:dd:dd:cd43
1632c19:dd:c25:c25d:dd:dd:dd:cd44/1272c19:dd:c25:c25d:dd:dd:dd:cd45
1642c19:dd:c25:c25d:dd:dd:dd:cd46/1272c19:dd:c25:c25d:dd:dd:dd:cd47
1652c19:dd:c25:c25d:dd:dd:dd:cd48/1272c19:dd:c25:c25d:dd:dd:dd:cd49
1662c19:dd:c25:c25d:dd:dd:dd:cd4a/1272c19:dd:c25:c25d:dd:dd:dd:cd4b
1672c19:dd:c25:c25d:dd:dd:dd:cd4c/1272c19:dd:c25:c25d:dd:dd:dd:cd4d
1682c19:dd:c25:c25d:dd:dd:dd:cd4e/1272c19:dd:c25:c25d:dd:dd:dd:cd4f
1692c19:dd:c25:c25d:dd:dd:dd:cd50/1272c19:dd:c25:c25d:dd:dd:dd:cd51
1702c19:dd:c25:c25d:dd:dd:dd:cd52/1272c19:dd:c25:c25d:dd:dd:dd:cd53
1712c19:dd:c25:c25d:dd:dd:dd:cd54/1272c19:dd:c25:c25d:dd:dd:dd:cd55
1722c19:dd:c25:c25d:dd:dd:dd:cd56/1272c19:dd:c25:c25d:dd:dd:dd:cd57
1732c19:dd:c25:c25d:dd:dd:dd:cd58/1272c19:dd:c25:c25d:dd:dd:dd:cd59
1742c19:dd:c25:c25d:dd:dd:dd:cd5a/1272c19:dd:c25:c25d:dd:dd:dd:cd5b
1752c19:dd:c25:c25d:dd:dd:dd:cd5c/1272c19:dd:c25:c25d:dd:dd:dd:cd5d
1762c19:dd:c25:c25d:dd:dd:dd:cd5e/1272c19:dd:c25:c25d:dd:dd:dd:cd5f
1772c19:dd:c25:c25d:dd:dd:dd:cd60/1272c19:dd:c25:c25d:dd:dd:dd:cd61
1782c19:dd:c25:c25d:dd:dd:dd:cd62/1272c19:dd:c25:c25d:dd:dd:dd:cd63
1792c19:dd:c25:c25d:dd:dd:dd:cd64/1272c19:dd:c25:c25d:dd:dd:dd:cd65
1802c19:dd:c25:c25d:dd:dd:dd:cd66/1272c19:dd:c25:c25d:dd:dd:dd:cd67
1812c19:dd:c25:c25d:dd:dd:dd:cd68/1272c19:dd:c25:c25d:dd:dd:dd:cd69
1822c19:dd:c25:c25d:dd:dd:dd:cd6a/1272c19:dd:c25:c25d:dd:dd:dd:cd6b
1832c19:dd:c25:c25d:dd:dd:dd:cd6c/1272c19:dd:c25:c25d:dd:dd:dd:cd6d
1842c19:dd:c25:c25d:dd:dd:dd:cd6e/1272c19:dd:c25:c25d:dd:dd:dd:cd6f
1852c19:dd:c25:c25d:dd:dd:dd:cd70/1272c19:dd:c25:c25d:dd:dd:dd:cd71
1862c19:dd:c25:c25d:dd:dd:dd:cd72/1272c19:dd:c25:c25d:dd:dd:dd:cd73
1872c19:dd:c25:c25d:dd:dd:dd:cd74/1272c19:dd:c25:c25d:dd:dd:dd:cd75
1882c19:dd:c25:c25d:dd:dd:dd:cd76/1272c19:dd:c25:c25d:dd:dd:dd:cd77
1892c19:dd:c25:c25d:dd:dd:dd:cd78/1272c19:dd:c25:c25d:dd:dd:dd:cd79
1902c19:dd:c25:c25d:dd:dd:dd:cd7a/1272c19:dd:c25:c25d:dd:dd:dd:cd7b
1912c19:dd:c25:c25d:dd:dd:dd:cd7c/1272c19:dd:c25:c25d:dd:dd:dd:cd7d
1922c19:dd:c25:c25d:dd:dd:dd:cd7e/1272c19:dd:c25:c25d:dd:dd:dd:cd7f
1932c19:dd:c25:c25d:dd:dd:dd:cd80/1272c19:dd:c25:c25d:dd:dd:dd:cd81
1942c19:dd:c25:c25d:dd:dd:dd:cd82/1272c19:dd:c25:c25d:dd:dd:dd:cd83
1952c19:dd:c25:c25d:dd:dd:dd:cd84/1272c19:dd:c25:c25d:dd:dd:dd:cd85
1962c19:dd:c25:c25d:dd:dd:dd:cd86/1272c19:dd:c25:c25d:dd:dd:dd:cd87
1972c19:dd:c25:c25d:dd:dd:dd:cd88/1272c19:dd:c25:c25d:dd:dd:dd:cd89
1982c19:dd:c25:c25d:dd:dd:dd:cd8a/1272c19:dd:c25:c25d:dd:dd:dd:cd8b
1992c19:dd:c25:c25d:dd:dd:dd:cd8c/1272c19:dd:c25:c25d:dd:dd:dd:cd8d
2002c19:dd:c25:c25d:dd:dd:dd:cd8e/1272c19:dd:c25:c25d:dd:dd:dd:cd8f
2012c19:dd:c25:c25d:dd:dd:dd:cd90/1272c19:dd:c25:c25d:dd:dd:dd:cd91
2022c19:dd:c25:c25d:dd:dd:dd:cd92/1272c19:dd:c25:c25d:dd:dd:dd:cd93
2032c19:dd:c25:c25d:dd:dd:dd:cd94/1272c19:dd:c25:c25d:dd:dd:dd:cd95
2042c19:dd:c25:c25d:dd:dd:dd:cd96/1272c19:dd:c25:c25d:dd:dd:dd:cd97
2052c19:dd:c25:c25d:dd:dd:dd:cd98/1272c19:dd:c25:c25d:dd:dd:dd:cd99
2062c19:dd:c25:c25d:dd:dd:dd:cd9a/1272c19:dd:c25:c25d:dd:dd:dd:cd9b
2072c19:dd:c25:c25d:dd:dd:dd:cd9c/1272c19:dd:c25:c25d:dd:dd:dd:cd9d
2082c19:dd:c25:c25d:dd:dd:dd:cd9e/1272c19:dd:c25:c25d:dd:dd:dd:cd9f
2092c19:dd:c25:c25d:dd:dd:dd:cda0/1272c19:dd:c25:c25d:dd:dd:dd:cda1
2102c19:dd:c25:c25d:dd:dd:dd:cda2/1272c19:dd:c25:c25d:dd:dd:dd:cda3
2112c19:dd:c25:c25d:dd:dd:dd:cda4/1272c19:dd:c25:c25d:dd:dd:dd:cda5
2122c19:dd:c25:c25d:dd:dd:dd:cda6/1272c19:dd:c25:c25d:dd:dd:dd:cda7
2132c19:dd:c25:c25d:dd:dd:dd:cda8/1272c19:dd:c25:c25d:dd:dd:dd:cda9
2142c19:dd:c25:c25d:dd:dd:dd:cdaa/1272c19:dd:c25:c25d:dd:dd:dd:cdab
2152c19:dd:c25:c25d:dd:dd:dd:cdac/1272c19:dd:c25:c25d:dd:dd:dd:cdad
2162c19:dd:c25:c25d:dd:dd:dd:cdae/1272c19:dd:c25:c25d:dd:dd:dd:cdaf
2172c19:dd:c25:c25d:dd:dd:dd:cdb0/1272c19:dd:c25:c25d:dd:dd:dd:cdb1
2182c19:dd:c25:c25d:dd:dd:dd:cdb2/1272c19:dd:c25:c25d:dd:dd:dd:cdb3
2192c19:dd:c25:c25d:dd:dd:dd:cdb4/1272c19:dd:c25:c25d:dd:dd:dd:cdb5
2202c19:dd:c25:c25d:dd:dd:dd:cdb6/1272c19:dd:c25:c25d:dd:dd:dd:cdb7
2212c19:dd:c25:c25d:dd:dd:dd:cdb8/1272c19:dd:c25:c25d:dd:dd:dd:cdb9
2222c19:dd:c25:c25d:dd:dd:dd:cdba/1272c19:dd:c25:c25d:dd:dd:dd:cdbb
2232c19:dd:c25:c25d:dd:dd:dd:cdbc/1272c19:dd:c25:c25d:dd:dd:dd:cdbd
2242c19:dd:c25:c25d:dd:dd:dd:cdbe/1272c19:dd:c25:c25d:dd:dd:dd:cdbf
2252c19:dd:c25:c25d:dd:dd:dd:cdc0/1272c19:dd:c25:c25d:dd:dd:dd:cdc1
2262c19:dd:c25:c25d:dd:dd:dd:cdc2/1272c19:dd:c25:c25d:dd:dd:dd:cdc3
2272c19:dd:c25:c25d:dd:dd:dd:cdc4/1272c19:dd:c25:c25d:dd:dd:dd:cdc5
2282c19:dd:c25:c25d:dd:dd:dd:cdc6/1272c19:dd:c25:c25d:dd:dd:dd:cdc7
2292c19:dd:c25:c25d:dd:dd:dd:cdc8/1272c19:dd:c25:c25d:dd:dd:dd:cdc9
2302c19:dd:c25:c25d:dd:dd:dd:cdca/1272c19:dd:c25:c25d:dd:dd:dd:cdcb
2312c19:dd:c25:c25d:dd:dd:dd:cdcc/1272c19:dd:c25:c25d:dd:dd:dd:cdcd
2322c19:dd:c25:c25d:dd:dd:dd:cdce/1272c19:dd:c25:c25d:dd:dd:dd:cdcf
2332c19:dd:c25:c25d:dd:dd:dd:cdd0/1272c19:dd:c25:c25d:dd:dd:dd:cdd1
2342c19:dd:c25:c25d:dd:dd:dd:cdd2/1272c19:dd:c25:c25d:dd:dd:dd:cdd3
2352c19:dd:c25:c25d:dd:dd:dd:cdd4/1272c19:dd:c25:c25d:dd:dd:dd:cdd5
2362c19:dd:c25:c25d:dd:dd:dd:cdd6/1272c19:dd:c25:c25d:dd:dd:dd:cdd7
2372c19:dd:c25:c25d:dd:dd:dd:cdd8/1272c19:dd:c25:c25d:dd:dd:dd:cdd9
2382c19:dd:c25:c25d:dd:dd:dd:cdda/1272c19:dd:c25:c25d:dd:dd:dd:cddb
2392c19:dd:c25:c25d:dd:dd:dd:cddc/1272c19:dd:c25:c25d:dd:dd:dd:cddd
2402c19:dd:c25:c25d:dd:dd:dd:cdde/1272c19:dd:c25:c25d:dd:dd:dd:cddf
2412c19:dd:c25:c25d:dd:dd:dd:cde0/1272c19:dd:c25:c25d:dd:dd:dd:cde1
2422c19:dd:c25:c25d:dd:dd:dd:cde2/1272c19:dd:c25:c25d:dd:dd:dd:cde3
2432c19:dd:c25:c25d:dd:dd:dd:cde4/1272c19:dd:c25:c25d:dd:dd:dd:cde5
2442c19:dd:c25:c25d:dd:dd:dd:cde6/1272c19:dd:c25:c25d:dd:dd:dd:cde7
2452c19:dd:c25:c25d:dd:dd:dd:cde8/1272c19:dd:c25:c25d:dd:dd:dd:cde9
2462c19:dd:c25:c25d:dd:dd:dd:cdea/1272c19:dd:c25:c25d:dd:dd:dd:cdeb
2472c19:dd:c25:c25d:dd:dd:dd:cdec/1272c19:dd:c25:c25d:dd:dd:dd:cded
2482c19:dd:c25:c25d:dd:dd:dd:cdee/1272c19:dd:c25:c25d:dd:dd:dd:cdef
2492c19:dd:c25:c25d:dd:dd:dd:cdf0/1272c19:dd:c25:c25d:dd:dd:dd:cdf1
2502c19:dd:c25:c25d:dd:dd:dd:cdf2/1272c19:dd:c25:c25d:dd:dd:dd:cdf3
2512c19:dd:c25:c25d:dd:dd:dd:cdf4/1272c19:dd:c25:c25d:dd:dd:dd:cdf5
2522c19:dd:c25:c25d:dd:dd:dd:cdf6/1272c19:dd:c25:c25d:dd:dd:dd:cdf7
2532c19:dd:c25:c25d:dd:dd:dd:cdf8/1272c19:dd:c25:c25d:dd:dd:dd:cdf9
2542c19:dd:c25:c25d:dd:dd:dd:cdfa/1272c19:dd:c25:c25d:dd:dd:dd:cdfb
2552c19:dd:c25:c25d:dd:dd:dd:cdfc/1272c19:dd:c25:c25d:dd:dd:dd:cdfd
2562c19:dd:c25:c25d:dd:dd:dd:cdfe/1272c19:dd:c25:c25d:dd:dd:dd:cdff

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.