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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/120
Addresses256
/64 networksPart of one
Network
2c19:dd:c25:c25d:dd:dd:dd:ae00/120
First address
2c19:dd:c25:c25d:dd:dd:dd:ae00
Last address
2c19:dd:c25:c25d:dd:dd:dd:aeff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:ae00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.a.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
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:c25:c25d:dd:dd:dd:ae00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:ae00/1282c19:dd:c25:c25d:dd:dd:dd:ae00
22c19:dd:c25:c25d:dd:dd:dd:ae01/1282c19:dd:c25:c25d:dd:dd:dd:ae01
32c19:dd:c25:c25d:dd:dd:dd:ae02/1282c19:dd:c25:c25d:dd:dd:dd:ae02
42c19:dd:c25:c25d:dd:dd:dd:ae03/1282c19:dd:c25:c25d:dd:dd:dd:ae03
52c19:dd:c25:c25d:dd:dd:dd:ae04/1282c19:dd:c25:c25d:dd:dd:dd:ae04
62c19:dd:c25:c25d:dd:dd:dd:ae05/1282c19:dd:c25:c25d:dd:dd:dd:ae05
72c19:dd:c25:c25d:dd:dd:dd:ae06/1282c19:dd:c25:c25d:dd:dd:dd:ae06
82c19:dd:c25:c25d:dd:dd:dd:ae07/1282c19:dd:c25:c25d:dd:dd:dd:ae07
92c19:dd:c25:c25d:dd:dd:dd:ae08/1282c19:dd:c25:c25d:dd:dd:dd:ae08
102c19:dd:c25:c25d:dd:dd:dd:ae09/1282c19:dd:c25:c25d:dd:dd:dd:ae09
112c19:dd:c25:c25d:dd:dd:dd:ae0a/1282c19:dd:c25:c25d:dd:dd:dd:ae0a
122c19:dd:c25:c25d:dd:dd:dd:ae0b/1282c19:dd:c25:c25d:dd:dd:dd:ae0b
132c19:dd:c25:c25d:dd:dd:dd:ae0c/1282c19:dd:c25:c25d:dd:dd:dd:ae0c
142c19:dd:c25:c25d:dd:dd:dd:ae0d/1282c19:dd:c25:c25d:dd:dd:dd:ae0d
152c19:dd:c25:c25d:dd:dd:dd:ae0e/1282c19:dd:c25:c25d:dd:dd:dd:ae0e
162c19:dd:c25:c25d:dd:dd:dd:ae0f/1282c19:dd:c25:c25d:dd:dd:dd:ae0f
172c19:dd:c25:c25d:dd:dd:dd:ae10/1282c19:dd:c25:c25d:dd:dd:dd:ae10
182c19:dd:c25:c25d:dd:dd:dd:ae11/1282c19:dd:c25:c25d:dd:dd:dd:ae11
192c19:dd:c25:c25d:dd:dd:dd:ae12/1282c19:dd:c25:c25d:dd:dd:dd:ae12
202c19:dd:c25:c25d:dd:dd:dd:ae13/1282c19:dd:c25:c25d:dd:dd:dd:ae13
212c19:dd:c25:c25d:dd:dd:dd:ae14/1282c19:dd:c25:c25d:dd:dd:dd:ae14
222c19:dd:c25:c25d:dd:dd:dd:ae15/1282c19:dd:c25:c25d:dd:dd:dd:ae15
232c19:dd:c25:c25d:dd:dd:dd:ae16/1282c19:dd:c25:c25d:dd:dd:dd:ae16
242c19:dd:c25:c25d:dd:dd:dd:ae17/1282c19:dd:c25:c25d:dd:dd:dd:ae17
252c19:dd:c25:c25d:dd:dd:dd:ae18/1282c19:dd:c25:c25d:dd:dd:dd:ae18
262c19:dd:c25:c25d:dd:dd:dd:ae19/1282c19:dd:c25:c25d:dd:dd:dd:ae19
272c19:dd:c25:c25d:dd:dd:dd:ae1a/1282c19:dd:c25:c25d:dd:dd:dd:ae1a
282c19:dd:c25:c25d:dd:dd:dd:ae1b/1282c19:dd:c25:c25d:dd:dd:dd:ae1b
292c19:dd:c25:c25d:dd:dd:dd:ae1c/1282c19:dd:c25:c25d:dd:dd:dd:ae1c
302c19:dd:c25:c25d:dd:dd:dd:ae1d/1282c19:dd:c25:c25d:dd:dd:dd:ae1d
312c19:dd:c25:c25d:dd:dd:dd:ae1e/1282c19:dd:c25:c25d:dd:dd:dd:ae1e
322c19:dd:c25:c25d:dd:dd:dd:ae1f/1282c19:dd:c25:c25d:dd:dd:dd:ae1f
332c19:dd:c25:c25d:dd:dd:dd:ae20/1282c19:dd:c25:c25d:dd:dd:dd:ae20
342c19:dd:c25:c25d:dd:dd:dd:ae21/1282c19:dd:c25:c25d:dd:dd:dd:ae21
352c19:dd:c25:c25d:dd:dd:dd:ae22/1282c19:dd:c25:c25d:dd:dd:dd:ae22
362c19:dd:c25:c25d:dd:dd:dd:ae23/1282c19:dd:c25:c25d:dd:dd:dd:ae23
372c19:dd:c25:c25d:dd:dd:dd:ae24/1282c19:dd:c25:c25d:dd:dd:dd:ae24
382c19:dd:c25:c25d:dd:dd:dd:ae25/1282c19:dd:c25:c25d:dd:dd:dd:ae25
392c19:dd:c25:c25d:dd:dd:dd:ae26/1282c19:dd:c25:c25d:dd:dd:dd:ae26
402c19:dd:c25:c25d:dd:dd:dd:ae27/1282c19:dd:c25:c25d:dd:dd:dd:ae27
412c19:dd:c25:c25d:dd:dd:dd:ae28/1282c19:dd:c25:c25d:dd:dd:dd:ae28
422c19:dd:c25:c25d:dd:dd:dd:ae29/1282c19:dd:c25:c25d:dd:dd:dd:ae29
432c19:dd:c25:c25d:dd:dd:dd:ae2a/1282c19:dd:c25:c25d:dd:dd:dd:ae2a
442c19:dd:c25:c25d:dd:dd:dd:ae2b/1282c19:dd:c25:c25d:dd:dd:dd:ae2b
452c19:dd:c25:c25d:dd:dd:dd:ae2c/1282c19:dd:c25:c25d:dd:dd:dd:ae2c
462c19:dd:c25:c25d:dd:dd:dd:ae2d/1282c19:dd:c25:c25d:dd:dd:dd:ae2d
472c19:dd:c25:c25d:dd:dd:dd:ae2e/1282c19:dd:c25:c25d:dd:dd:dd:ae2e
482c19:dd:c25:c25d:dd:dd:dd:ae2f/1282c19:dd:c25:c25d:dd:dd:dd:ae2f
492c19:dd:c25:c25d:dd:dd:dd:ae30/1282c19:dd:c25:c25d:dd:dd:dd:ae30
502c19:dd:c25:c25d:dd:dd:dd:ae31/1282c19:dd:c25:c25d:dd:dd:dd:ae31
512c19:dd:c25:c25d:dd:dd:dd:ae32/1282c19:dd:c25:c25d:dd:dd:dd:ae32
522c19:dd:c25:c25d:dd:dd:dd:ae33/1282c19:dd:c25:c25d:dd:dd:dd:ae33
532c19:dd:c25:c25d:dd:dd:dd:ae34/1282c19:dd:c25:c25d:dd:dd:dd:ae34
542c19:dd:c25:c25d:dd:dd:dd:ae35/1282c19:dd:c25:c25d:dd:dd:dd:ae35
552c19:dd:c25:c25d:dd:dd:dd:ae36/1282c19:dd:c25:c25d:dd:dd:dd:ae36
562c19:dd:c25:c25d:dd:dd:dd:ae37/1282c19:dd:c25:c25d:dd:dd:dd:ae37
572c19:dd:c25:c25d:dd:dd:dd:ae38/1282c19:dd:c25:c25d:dd:dd:dd:ae38
582c19:dd:c25:c25d:dd:dd:dd:ae39/1282c19:dd:c25:c25d:dd:dd:dd:ae39
592c19:dd:c25:c25d:dd:dd:dd:ae3a/1282c19:dd:c25:c25d:dd:dd:dd:ae3a
602c19:dd:c25:c25d:dd:dd:dd:ae3b/1282c19:dd:c25:c25d:dd:dd:dd:ae3b
612c19:dd:c25:c25d:dd:dd:dd:ae3c/1282c19:dd:c25:c25d:dd:dd:dd:ae3c
622c19:dd:c25:c25d:dd:dd:dd:ae3d/1282c19:dd:c25:c25d:dd:dd:dd:ae3d
632c19:dd:c25:c25d:dd:dd:dd:ae3e/1282c19:dd:c25:c25d:dd:dd:dd:ae3e
642c19:dd:c25:c25d:dd:dd:dd:ae3f/1282c19:dd:c25:c25d:dd:dd:dd:ae3f
652c19:dd:c25:c25d:dd:dd:dd:ae40/1282c19:dd:c25:c25d:dd:dd:dd:ae40
662c19:dd:c25:c25d:dd:dd:dd:ae41/1282c19:dd:c25:c25d:dd:dd:dd:ae41
672c19:dd:c25:c25d:dd:dd:dd:ae42/1282c19:dd:c25:c25d:dd:dd:dd:ae42
682c19:dd:c25:c25d:dd:dd:dd:ae43/1282c19:dd:c25:c25d:dd:dd:dd:ae43
692c19:dd:c25:c25d:dd:dd:dd:ae44/1282c19:dd:c25:c25d:dd:dd:dd:ae44
702c19:dd:c25:c25d:dd:dd:dd:ae45/1282c19:dd:c25:c25d:dd:dd:dd:ae45
712c19:dd:c25:c25d:dd:dd:dd:ae46/1282c19:dd:c25:c25d:dd:dd:dd:ae46
722c19:dd:c25:c25d:dd:dd:dd:ae47/1282c19:dd:c25:c25d:dd:dd:dd:ae47
732c19:dd:c25:c25d:dd:dd:dd:ae48/1282c19:dd:c25:c25d:dd:dd:dd:ae48
742c19:dd:c25:c25d:dd:dd:dd:ae49/1282c19:dd:c25:c25d:dd:dd:dd:ae49
752c19:dd:c25:c25d:dd:dd:dd:ae4a/1282c19:dd:c25:c25d:dd:dd:dd:ae4a
762c19:dd:c25:c25d:dd:dd:dd:ae4b/1282c19:dd:c25:c25d:dd:dd:dd:ae4b
772c19:dd:c25:c25d:dd:dd:dd:ae4c/1282c19:dd:c25:c25d:dd:dd:dd:ae4c
782c19:dd:c25:c25d:dd:dd:dd:ae4d/1282c19:dd:c25:c25d:dd:dd:dd:ae4d
792c19:dd:c25:c25d:dd:dd:dd:ae4e/1282c19:dd:c25:c25d:dd:dd:dd:ae4e
802c19:dd:c25:c25d:dd:dd:dd:ae4f/1282c19:dd:c25:c25d:dd:dd:dd:ae4f
812c19:dd:c25:c25d:dd:dd:dd:ae50/1282c19:dd:c25:c25d:dd:dd:dd:ae50
822c19:dd:c25:c25d:dd:dd:dd:ae51/1282c19:dd:c25:c25d:dd:dd:dd:ae51
832c19:dd:c25:c25d:dd:dd:dd:ae52/1282c19:dd:c25:c25d:dd:dd:dd:ae52
842c19:dd:c25:c25d:dd:dd:dd:ae53/1282c19:dd:c25:c25d:dd:dd:dd:ae53
852c19:dd:c25:c25d:dd:dd:dd:ae54/1282c19:dd:c25:c25d:dd:dd:dd:ae54
862c19:dd:c25:c25d:dd:dd:dd:ae55/1282c19:dd:c25:c25d:dd:dd:dd:ae55
872c19:dd:c25:c25d:dd:dd:dd:ae56/1282c19:dd:c25:c25d:dd:dd:dd:ae56
882c19:dd:c25:c25d:dd:dd:dd:ae57/1282c19:dd:c25:c25d:dd:dd:dd:ae57
892c19:dd:c25:c25d:dd:dd:dd:ae58/1282c19:dd:c25:c25d:dd:dd:dd:ae58
902c19:dd:c25:c25d:dd:dd:dd:ae59/1282c19:dd:c25:c25d:dd:dd:dd:ae59
912c19:dd:c25:c25d:dd:dd:dd:ae5a/1282c19:dd:c25:c25d:dd:dd:dd:ae5a
922c19:dd:c25:c25d:dd:dd:dd:ae5b/1282c19:dd:c25:c25d:dd:dd:dd:ae5b
932c19:dd:c25:c25d:dd:dd:dd:ae5c/1282c19:dd:c25:c25d:dd:dd:dd:ae5c
942c19:dd:c25:c25d:dd:dd:dd:ae5d/1282c19:dd:c25:c25d:dd:dd:dd:ae5d
952c19:dd:c25:c25d:dd:dd:dd:ae5e/1282c19:dd:c25:c25d:dd:dd:dd:ae5e
962c19:dd:c25:c25d:dd:dd:dd:ae5f/1282c19:dd:c25:c25d:dd:dd:dd:ae5f
972c19:dd:c25:c25d:dd:dd:dd:ae60/1282c19:dd:c25:c25d:dd:dd:dd:ae60
982c19:dd:c25:c25d:dd:dd:dd:ae61/1282c19:dd:c25:c25d:dd:dd:dd:ae61
992c19:dd:c25:c25d:dd:dd:dd:ae62/1282c19:dd:c25:c25d:dd:dd:dd:ae62
1002c19:dd:c25:c25d:dd:dd:dd:ae63/1282c19:dd:c25:c25d:dd:dd:dd:ae63
1012c19:dd:c25:c25d:dd:dd:dd:ae64/1282c19:dd:c25:c25d:dd:dd:dd:ae64
1022c19:dd:c25:c25d:dd:dd:dd:ae65/1282c19:dd:c25:c25d:dd:dd:dd:ae65
1032c19:dd:c25:c25d:dd:dd:dd:ae66/1282c19:dd:c25:c25d:dd:dd:dd:ae66
1042c19:dd:c25:c25d:dd:dd:dd:ae67/1282c19:dd:c25:c25d:dd:dd:dd:ae67
1052c19:dd:c25:c25d:dd:dd:dd:ae68/1282c19:dd:c25:c25d:dd:dd:dd:ae68
1062c19:dd:c25:c25d:dd:dd:dd:ae69/1282c19:dd:c25:c25d:dd:dd:dd:ae69
1072c19:dd:c25:c25d:dd:dd:dd:ae6a/1282c19:dd:c25:c25d:dd:dd:dd:ae6a
1082c19:dd:c25:c25d:dd:dd:dd:ae6b/1282c19:dd:c25:c25d:dd:dd:dd:ae6b
1092c19:dd:c25:c25d:dd:dd:dd:ae6c/1282c19:dd:c25:c25d:dd:dd:dd:ae6c
1102c19:dd:c25:c25d:dd:dd:dd:ae6d/1282c19:dd:c25:c25d:dd:dd:dd:ae6d
1112c19:dd:c25:c25d:dd:dd:dd:ae6e/1282c19:dd:c25:c25d:dd:dd:dd:ae6e
1122c19:dd:c25:c25d:dd:dd:dd:ae6f/1282c19:dd:c25:c25d:dd:dd:dd:ae6f
1132c19:dd:c25:c25d:dd:dd:dd:ae70/1282c19:dd:c25:c25d:dd:dd:dd:ae70
1142c19:dd:c25:c25d:dd:dd:dd:ae71/1282c19:dd:c25:c25d:dd:dd:dd:ae71
1152c19:dd:c25:c25d:dd:dd:dd:ae72/1282c19:dd:c25:c25d:dd:dd:dd:ae72
1162c19:dd:c25:c25d:dd:dd:dd:ae73/1282c19:dd:c25:c25d:dd:dd:dd:ae73
1172c19:dd:c25:c25d:dd:dd:dd:ae74/1282c19:dd:c25:c25d:dd:dd:dd:ae74
1182c19:dd:c25:c25d:dd:dd:dd:ae75/1282c19:dd:c25:c25d:dd:dd:dd:ae75
1192c19:dd:c25:c25d:dd:dd:dd:ae76/1282c19:dd:c25:c25d:dd:dd:dd:ae76
1202c19:dd:c25:c25d:dd:dd:dd:ae77/1282c19:dd:c25:c25d:dd:dd:dd:ae77
1212c19:dd:c25:c25d:dd:dd:dd:ae78/1282c19:dd:c25:c25d:dd:dd:dd:ae78
1222c19:dd:c25:c25d:dd:dd:dd:ae79/1282c19:dd:c25:c25d:dd:dd:dd:ae79
1232c19:dd:c25:c25d:dd:dd:dd:ae7a/1282c19:dd:c25:c25d:dd:dd:dd:ae7a
1242c19:dd:c25:c25d:dd:dd:dd:ae7b/1282c19:dd:c25:c25d:dd:dd:dd:ae7b
1252c19:dd:c25:c25d:dd:dd:dd:ae7c/1282c19:dd:c25:c25d:dd:dd:dd:ae7c
1262c19:dd:c25:c25d:dd:dd:dd:ae7d/1282c19:dd:c25:c25d:dd:dd:dd:ae7d
1272c19:dd:c25:c25d:dd:dd:dd:ae7e/1282c19:dd:c25:c25d:dd:dd:dd:ae7e
1282c19:dd:c25:c25d:dd:dd:dd:ae7f/1282c19:dd:c25:c25d:dd:dd:dd:ae7f
1292c19:dd:c25:c25d:dd:dd:dd:ae80/1282c19:dd:c25:c25d:dd:dd:dd:ae80
1302c19:dd:c25:c25d:dd:dd:dd:ae81/1282c19:dd:c25:c25d:dd:dd:dd:ae81
1312c19:dd:c25:c25d:dd:dd:dd:ae82/1282c19:dd:c25:c25d:dd:dd:dd:ae82
1322c19:dd:c25:c25d:dd:dd:dd:ae83/1282c19:dd:c25:c25d:dd:dd:dd:ae83
1332c19:dd:c25:c25d:dd:dd:dd:ae84/1282c19:dd:c25:c25d:dd:dd:dd:ae84
1342c19:dd:c25:c25d:dd:dd:dd:ae85/1282c19:dd:c25:c25d:dd:dd:dd:ae85
1352c19:dd:c25:c25d:dd:dd:dd:ae86/1282c19:dd:c25:c25d:dd:dd:dd:ae86
1362c19:dd:c25:c25d:dd:dd:dd:ae87/1282c19:dd:c25:c25d:dd:dd:dd:ae87
1372c19:dd:c25:c25d:dd:dd:dd:ae88/1282c19:dd:c25:c25d:dd:dd:dd:ae88
1382c19:dd:c25:c25d:dd:dd:dd:ae89/1282c19:dd:c25:c25d:dd:dd:dd:ae89
1392c19:dd:c25:c25d:dd:dd:dd:ae8a/1282c19:dd:c25:c25d:dd:dd:dd:ae8a
1402c19:dd:c25:c25d:dd:dd:dd:ae8b/1282c19:dd:c25:c25d:dd:dd:dd:ae8b
1412c19:dd:c25:c25d:dd:dd:dd:ae8c/1282c19:dd:c25:c25d:dd:dd:dd:ae8c
1422c19:dd:c25:c25d:dd:dd:dd:ae8d/1282c19:dd:c25:c25d:dd:dd:dd:ae8d
1432c19:dd:c25:c25d:dd:dd:dd:ae8e/1282c19:dd:c25:c25d:dd:dd:dd:ae8e
1442c19:dd:c25:c25d:dd:dd:dd:ae8f/1282c19:dd:c25:c25d:dd:dd:dd:ae8f
1452c19:dd:c25:c25d:dd:dd:dd:ae90/1282c19:dd:c25:c25d:dd:dd:dd:ae90
1462c19:dd:c25:c25d:dd:dd:dd:ae91/1282c19:dd:c25:c25d:dd:dd:dd:ae91
1472c19:dd:c25:c25d:dd:dd:dd:ae92/1282c19:dd:c25:c25d:dd:dd:dd:ae92
1482c19:dd:c25:c25d:dd:dd:dd:ae93/1282c19:dd:c25:c25d:dd:dd:dd:ae93
1492c19:dd:c25:c25d:dd:dd:dd:ae94/1282c19:dd:c25:c25d:dd:dd:dd:ae94
1502c19:dd:c25:c25d:dd:dd:dd:ae95/1282c19:dd:c25:c25d:dd:dd:dd:ae95
1512c19:dd:c25:c25d:dd:dd:dd:ae96/1282c19:dd:c25:c25d:dd:dd:dd:ae96
1522c19:dd:c25:c25d:dd:dd:dd:ae97/1282c19:dd:c25:c25d:dd:dd:dd:ae97
1532c19:dd:c25:c25d:dd:dd:dd:ae98/1282c19:dd:c25:c25d:dd:dd:dd:ae98
1542c19:dd:c25:c25d:dd:dd:dd:ae99/1282c19:dd:c25:c25d:dd:dd:dd:ae99
1552c19:dd:c25:c25d:dd:dd:dd:ae9a/1282c19:dd:c25:c25d:dd:dd:dd:ae9a
1562c19:dd:c25:c25d:dd:dd:dd:ae9b/1282c19:dd:c25:c25d:dd:dd:dd:ae9b
1572c19:dd:c25:c25d:dd:dd:dd:ae9c/1282c19:dd:c25:c25d:dd:dd:dd:ae9c
1582c19:dd:c25:c25d:dd:dd:dd:ae9d/1282c19:dd:c25:c25d:dd:dd:dd:ae9d
1592c19:dd:c25:c25d:dd:dd:dd:ae9e/1282c19:dd:c25:c25d:dd:dd:dd:ae9e
1602c19:dd:c25:c25d:dd:dd:dd:ae9f/1282c19:dd:c25:c25d:dd:dd:dd:ae9f
1612c19:dd:c25:c25d:dd:dd:dd:aea0/1282c19:dd:c25:c25d:dd:dd:dd:aea0
1622c19:dd:c25:c25d:dd:dd:dd:aea1/1282c19:dd:c25:c25d:dd:dd:dd:aea1
1632c19:dd:c25:c25d:dd:dd:dd:aea2/1282c19:dd:c25:c25d:dd:dd:dd:aea2
1642c19:dd:c25:c25d:dd:dd:dd:aea3/1282c19:dd:c25:c25d:dd:dd:dd:aea3
1652c19:dd:c25:c25d:dd:dd:dd:aea4/1282c19:dd:c25:c25d:dd:dd:dd:aea4
1662c19:dd:c25:c25d:dd:dd:dd:aea5/1282c19:dd:c25:c25d:dd:dd:dd:aea5
1672c19:dd:c25:c25d:dd:dd:dd:aea6/1282c19:dd:c25:c25d:dd:dd:dd:aea6
1682c19:dd:c25:c25d:dd:dd:dd:aea7/1282c19:dd:c25:c25d:dd:dd:dd:aea7
1692c19:dd:c25:c25d:dd:dd:dd:aea8/1282c19:dd:c25:c25d:dd:dd:dd:aea8
1702c19:dd:c25:c25d:dd:dd:dd:aea9/1282c19:dd:c25:c25d:dd:dd:dd:aea9
1712c19:dd:c25:c25d:dd:dd:dd:aeaa/1282c19:dd:c25:c25d:dd:dd:dd:aeaa
1722c19:dd:c25:c25d:dd:dd:dd:aeab/1282c19:dd:c25:c25d:dd:dd:dd:aeab
1732c19:dd:c25:c25d:dd:dd:dd:aeac/1282c19:dd:c25:c25d:dd:dd:dd:aeac
1742c19:dd:c25:c25d:dd:dd:dd:aead/1282c19:dd:c25:c25d:dd:dd:dd:aead
1752c19:dd:c25:c25d:dd:dd:dd:aeae/1282c19:dd:c25:c25d:dd:dd:dd:aeae
1762c19:dd:c25:c25d:dd:dd:dd:aeaf/1282c19:dd:c25:c25d:dd:dd:dd:aeaf
1772c19:dd:c25:c25d:dd:dd:dd:aeb0/1282c19:dd:c25:c25d:dd:dd:dd:aeb0
1782c19:dd:c25:c25d:dd:dd:dd:aeb1/1282c19:dd:c25:c25d:dd:dd:dd:aeb1
1792c19:dd:c25:c25d:dd:dd:dd:aeb2/1282c19:dd:c25:c25d:dd:dd:dd:aeb2
1802c19:dd:c25:c25d:dd:dd:dd:aeb3/1282c19:dd:c25:c25d:dd:dd:dd:aeb3
1812c19:dd:c25:c25d:dd:dd:dd:aeb4/1282c19:dd:c25:c25d:dd:dd:dd:aeb4
1822c19:dd:c25:c25d:dd:dd:dd:aeb5/1282c19:dd:c25:c25d:dd:dd:dd:aeb5
1832c19:dd:c25:c25d:dd:dd:dd:aeb6/1282c19:dd:c25:c25d:dd:dd:dd:aeb6
1842c19:dd:c25:c25d:dd:dd:dd:aeb7/1282c19:dd:c25:c25d:dd:dd:dd:aeb7
1852c19:dd:c25:c25d:dd:dd:dd:aeb8/1282c19:dd:c25:c25d:dd:dd:dd:aeb8
1862c19:dd:c25:c25d:dd:dd:dd:aeb9/1282c19:dd:c25:c25d:dd:dd:dd:aeb9
1872c19:dd:c25:c25d:dd:dd:dd:aeba/1282c19:dd:c25:c25d:dd:dd:dd:aeba
1882c19:dd:c25:c25d:dd:dd:dd:aebb/1282c19:dd:c25:c25d:dd:dd:dd:aebb
1892c19:dd:c25:c25d:dd:dd:dd:aebc/1282c19:dd:c25:c25d:dd:dd:dd:aebc
1902c19:dd:c25:c25d:dd:dd:dd:aebd/1282c19:dd:c25:c25d:dd:dd:dd:aebd
1912c19:dd:c25:c25d:dd:dd:dd:aebe/1282c19:dd:c25:c25d:dd:dd:dd:aebe
1922c19:dd:c25:c25d:dd:dd:dd:aebf/1282c19:dd:c25:c25d:dd:dd:dd:aebf
1932c19:dd:c25:c25d:dd:dd:dd:aec0/1282c19:dd:c25:c25d:dd:dd:dd:aec0
1942c19:dd:c25:c25d:dd:dd:dd:aec1/1282c19:dd:c25:c25d:dd:dd:dd:aec1
1952c19:dd:c25:c25d:dd:dd:dd:aec2/1282c19:dd:c25:c25d:dd:dd:dd:aec2
1962c19:dd:c25:c25d:dd:dd:dd:aec3/1282c19:dd:c25:c25d:dd:dd:dd:aec3
1972c19:dd:c25:c25d:dd:dd:dd:aec4/1282c19:dd:c25:c25d:dd:dd:dd:aec4
1982c19:dd:c25:c25d:dd:dd:dd:aec5/1282c19:dd:c25:c25d:dd:dd:dd:aec5
1992c19:dd:c25:c25d:dd:dd:dd:aec6/1282c19:dd:c25:c25d:dd:dd:dd:aec6
2002c19:dd:c25:c25d:dd:dd:dd:aec7/1282c19:dd:c25:c25d:dd:dd:dd:aec7
2012c19:dd:c25:c25d:dd:dd:dd:aec8/1282c19:dd:c25:c25d:dd:dd:dd:aec8
2022c19:dd:c25:c25d:dd:dd:dd:aec9/1282c19:dd:c25:c25d:dd:dd:dd:aec9
2032c19:dd:c25:c25d:dd:dd:dd:aeca/1282c19:dd:c25:c25d:dd:dd:dd:aeca
2042c19:dd:c25:c25d:dd:dd:dd:aecb/1282c19:dd:c25:c25d:dd:dd:dd:aecb
2052c19:dd:c25:c25d:dd:dd:dd:aecc/1282c19:dd:c25:c25d:dd:dd:dd:aecc
2062c19:dd:c25:c25d:dd:dd:dd:aecd/1282c19:dd:c25:c25d:dd:dd:dd:aecd
2072c19:dd:c25:c25d:dd:dd:dd:aece/1282c19:dd:c25:c25d:dd:dd:dd:aece
2082c19:dd:c25:c25d:dd:dd:dd:aecf/1282c19:dd:c25:c25d:dd:dd:dd:aecf
2092c19:dd:c25:c25d:dd:dd:dd:aed0/1282c19:dd:c25:c25d:dd:dd:dd:aed0
2102c19:dd:c25:c25d:dd:dd:dd:aed1/1282c19:dd:c25:c25d:dd:dd:dd:aed1
2112c19:dd:c25:c25d:dd:dd:dd:aed2/1282c19:dd:c25:c25d:dd:dd:dd:aed2
2122c19:dd:c25:c25d:dd:dd:dd:aed3/1282c19:dd:c25:c25d:dd:dd:dd:aed3
2132c19:dd:c25:c25d:dd:dd:dd:aed4/1282c19:dd:c25:c25d:dd:dd:dd:aed4
2142c19:dd:c25:c25d:dd:dd:dd:aed5/1282c19:dd:c25:c25d:dd:dd:dd:aed5
2152c19:dd:c25:c25d:dd:dd:dd:aed6/1282c19:dd:c25:c25d:dd:dd:dd:aed6
2162c19:dd:c25:c25d:dd:dd:dd:aed7/1282c19:dd:c25:c25d:dd:dd:dd:aed7
2172c19:dd:c25:c25d:dd:dd:dd:aed8/1282c19:dd:c25:c25d:dd:dd:dd:aed8
2182c19:dd:c25:c25d:dd:dd:dd:aed9/1282c19:dd:c25:c25d:dd:dd:dd:aed9
2192c19:dd:c25:c25d:dd:dd:dd:aeda/1282c19:dd:c25:c25d:dd:dd:dd:aeda
2202c19:dd:c25:c25d:dd:dd:dd:aedb/1282c19:dd:c25:c25d:dd:dd:dd:aedb
2212c19:dd:c25:c25d:dd:dd:dd:aedc/1282c19:dd:c25:c25d:dd:dd:dd:aedc
2222c19:dd:c25:c25d:dd:dd:dd:aedd/1282c19:dd:c25:c25d:dd:dd:dd:aedd
2232c19:dd:c25:c25d:dd:dd:dd:aede/1282c19:dd:c25:c25d:dd:dd:dd:aede
2242c19:dd:c25:c25d:dd:dd:dd:aedf/1282c19:dd:c25:c25d:dd:dd:dd:aedf
2252c19:dd:c25:c25d:dd:dd:dd:aee0/1282c19:dd:c25:c25d:dd:dd:dd:aee0
2262c19:dd:c25:c25d:dd:dd:dd:aee1/1282c19:dd:c25:c25d:dd:dd:dd:aee1
2272c19:dd:c25:c25d:dd:dd:dd:aee2/1282c19:dd:c25:c25d:dd:dd:dd:aee2
2282c19:dd:c25:c25d:dd:dd:dd:aee3/1282c19:dd:c25:c25d:dd:dd:dd:aee3
2292c19:dd:c25:c25d:dd:dd:dd:aee4/1282c19:dd:c25:c25d:dd:dd:dd:aee4
2302c19:dd:c25:c25d:dd:dd:dd:aee5/1282c19:dd:c25:c25d:dd:dd:dd:aee5
2312c19:dd:c25:c25d:dd:dd:dd:aee6/1282c19:dd:c25:c25d:dd:dd:dd:aee6
2322c19:dd:c25:c25d:dd:dd:dd:aee7/1282c19:dd:c25:c25d:dd:dd:dd:aee7
2332c19:dd:c25:c25d:dd:dd:dd:aee8/1282c19:dd:c25:c25d:dd:dd:dd:aee8
2342c19:dd:c25:c25d:dd:dd:dd:aee9/1282c19:dd:c25:c25d:dd:dd:dd:aee9
2352c19:dd:c25:c25d:dd:dd:dd:aeea/1282c19:dd:c25:c25d:dd:dd:dd:aeea
2362c19:dd:c25:c25d:dd:dd:dd:aeeb/1282c19:dd:c25:c25d:dd:dd:dd:aeeb
2372c19:dd:c25:c25d:dd:dd:dd:aeec/1282c19:dd:c25:c25d:dd:dd:dd:aeec
2382c19:dd:c25:c25d:dd:dd:dd:aeed/1282c19:dd:c25:c25d:dd:dd:dd:aeed
2392c19:dd:c25:c25d:dd:dd:dd:aeee/1282c19:dd:c25:c25d:dd:dd:dd:aeee
2402c19:dd:c25:c25d:dd:dd:dd:aeef/1282c19:dd:c25:c25d:dd:dd:dd:aeef
2412c19:dd:c25:c25d:dd:dd:dd:aef0/1282c19:dd:c25:c25d:dd:dd:dd:aef0
2422c19:dd:c25:c25d:dd:dd:dd:aef1/1282c19:dd:c25:c25d:dd:dd:dd:aef1
2432c19:dd:c25:c25d:dd:dd:dd:aef2/1282c19:dd:c25:c25d:dd:dd:dd:aef2
2442c19:dd:c25:c25d:dd:dd:dd:aef3/1282c19:dd:c25:c25d:dd:dd:dd:aef3
2452c19:dd:c25:c25d:dd:dd:dd:aef4/1282c19:dd:c25:c25d:dd:dd:dd:aef4
2462c19:dd:c25:c25d:dd:dd:dd:aef5/1282c19:dd:c25:c25d:dd:dd:dd:aef5
2472c19:dd:c25:c25d:dd:dd:dd:aef6/1282c19:dd:c25:c25d:dd:dd:dd:aef6
2482c19:dd:c25:c25d:dd:dd:dd:aef7/1282c19:dd:c25:c25d:dd:dd:dd:aef7
2492c19:dd:c25:c25d:dd:dd:dd:aef8/1282c19:dd:c25:c25d:dd:dd:dd:aef8
2502c19:dd:c25:c25d:dd:dd:dd:aef9/1282c19:dd:c25:c25d:dd:dd:dd:aef9
2512c19:dd:c25:c25d:dd:dd:dd:aefa/1282c19:dd:c25:c25d:dd:dd:dd:aefa
2522c19:dd:c25:c25d:dd:dd:dd:aefb/1282c19:dd:c25:c25d:dd:dd:dd:aefb
2532c19:dd:c25:c25d:dd:dd:dd:aefc/1282c19:dd:c25:c25d:dd:dd:dd:aefc
2542c19:dd:c25:c25d:dd:dd:dd:aefd/1282c19:dd:c25:c25d:dd:dd:dd:aefd
2552c19:dd:c25:c25d:dd:dd:dd:aefe/1282c19:dd:c25:c25d:dd:dd:dd:aefe
2562c19:dd:c25:c25d:dd:dd:dd:aeff/1282c19:dd:c25:c25d:dd:dd:dd:aeff

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.