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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:ba00/120
First address
2c19:dd:c25:c25d:dd:dd:dd:ba00
Last address
2c19:dd:c25:c25d:dd:dd:dd:baff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:ba00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
a.b.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:ba00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:ba00/1282c19:dd:c25:c25d:dd:dd:dd:ba00
22c19:dd:c25:c25d:dd:dd:dd:ba01/1282c19:dd:c25:c25d:dd:dd:dd:ba01
32c19:dd:c25:c25d:dd:dd:dd:ba02/1282c19:dd:c25:c25d:dd:dd:dd:ba02
42c19:dd:c25:c25d:dd:dd:dd:ba03/1282c19:dd:c25:c25d:dd:dd:dd:ba03
52c19:dd:c25:c25d:dd:dd:dd:ba04/1282c19:dd:c25:c25d:dd:dd:dd:ba04
62c19:dd:c25:c25d:dd:dd:dd:ba05/1282c19:dd:c25:c25d:dd:dd:dd:ba05
72c19:dd:c25:c25d:dd:dd:dd:ba06/1282c19:dd:c25:c25d:dd:dd:dd:ba06
82c19:dd:c25:c25d:dd:dd:dd:ba07/1282c19:dd:c25:c25d:dd:dd:dd:ba07
92c19:dd:c25:c25d:dd:dd:dd:ba08/1282c19:dd:c25:c25d:dd:dd:dd:ba08
102c19:dd:c25:c25d:dd:dd:dd:ba09/1282c19:dd:c25:c25d:dd:dd:dd:ba09
112c19:dd:c25:c25d:dd:dd:dd:ba0a/1282c19:dd:c25:c25d:dd:dd:dd:ba0a
122c19:dd:c25:c25d:dd:dd:dd:ba0b/1282c19:dd:c25:c25d:dd:dd:dd:ba0b
132c19:dd:c25:c25d:dd:dd:dd:ba0c/1282c19:dd:c25:c25d:dd:dd:dd:ba0c
142c19:dd:c25:c25d:dd:dd:dd:ba0d/1282c19:dd:c25:c25d:dd:dd:dd:ba0d
152c19:dd:c25:c25d:dd:dd:dd:ba0e/1282c19:dd:c25:c25d:dd:dd:dd:ba0e
162c19:dd:c25:c25d:dd:dd:dd:ba0f/1282c19:dd:c25:c25d:dd:dd:dd:ba0f
172c19:dd:c25:c25d:dd:dd:dd:ba10/1282c19:dd:c25:c25d:dd:dd:dd:ba10
182c19:dd:c25:c25d:dd:dd:dd:ba11/1282c19:dd:c25:c25d:dd:dd:dd:ba11
192c19:dd:c25:c25d:dd:dd:dd:ba12/1282c19:dd:c25:c25d:dd:dd:dd:ba12
202c19:dd:c25:c25d:dd:dd:dd:ba13/1282c19:dd:c25:c25d:dd:dd:dd:ba13
212c19:dd:c25:c25d:dd:dd:dd:ba14/1282c19:dd:c25:c25d:dd:dd:dd:ba14
222c19:dd:c25:c25d:dd:dd:dd:ba15/1282c19:dd:c25:c25d:dd:dd:dd:ba15
232c19:dd:c25:c25d:dd:dd:dd:ba16/1282c19:dd:c25:c25d:dd:dd:dd:ba16
242c19:dd:c25:c25d:dd:dd:dd:ba17/1282c19:dd:c25:c25d:dd:dd:dd:ba17
252c19:dd:c25:c25d:dd:dd:dd:ba18/1282c19:dd:c25:c25d:dd:dd:dd:ba18
262c19:dd:c25:c25d:dd:dd:dd:ba19/1282c19:dd:c25:c25d:dd:dd:dd:ba19
272c19:dd:c25:c25d:dd:dd:dd:ba1a/1282c19:dd:c25:c25d:dd:dd:dd:ba1a
282c19:dd:c25:c25d:dd:dd:dd:ba1b/1282c19:dd:c25:c25d:dd:dd:dd:ba1b
292c19:dd:c25:c25d:dd:dd:dd:ba1c/1282c19:dd:c25:c25d:dd:dd:dd:ba1c
302c19:dd:c25:c25d:dd:dd:dd:ba1d/1282c19:dd:c25:c25d:dd:dd:dd:ba1d
312c19:dd:c25:c25d:dd:dd:dd:ba1e/1282c19:dd:c25:c25d:dd:dd:dd:ba1e
322c19:dd:c25:c25d:dd:dd:dd:ba1f/1282c19:dd:c25:c25d:dd:dd:dd:ba1f
332c19:dd:c25:c25d:dd:dd:dd:ba20/1282c19:dd:c25:c25d:dd:dd:dd:ba20
342c19:dd:c25:c25d:dd:dd:dd:ba21/1282c19:dd:c25:c25d:dd:dd:dd:ba21
352c19:dd:c25:c25d:dd:dd:dd:ba22/1282c19:dd:c25:c25d:dd:dd:dd:ba22
362c19:dd:c25:c25d:dd:dd:dd:ba23/1282c19:dd:c25:c25d:dd:dd:dd:ba23
372c19:dd:c25:c25d:dd:dd:dd:ba24/1282c19:dd:c25:c25d:dd:dd:dd:ba24
382c19:dd:c25:c25d:dd:dd:dd:ba25/1282c19:dd:c25:c25d:dd:dd:dd:ba25
392c19:dd:c25:c25d:dd:dd:dd:ba26/1282c19:dd:c25:c25d:dd:dd:dd:ba26
402c19:dd:c25:c25d:dd:dd:dd:ba27/1282c19:dd:c25:c25d:dd:dd:dd:ba27
412c19:dd:c25:c25d:dd:dd:dd:ba28/1282c19:dd:c25:c25d:dd:dd:dd:ba28
422c19:dd:c25:c25d:dd:dd:dd:ba29/1282c19:dd:c25:c25d:dd:dd:dd:ba29
432c19:dd:c25:c25d:dd:dd:dd:ba2a/1282c19:dd:c25:c25d:dd:dd:dd:ba2a
442c19:dd:c25:c25d:dd:dd:dd:ba2b/1282c19:dd:c25:c25d:dd:dd:dd:ba2b
452c19:dd:c25:c25d:dd:dd:dd:ba2c/1282c19:dd:c25:c25d:dd:dd:dd:ba2c
462c19:dd:c25:c25d:dd:dd:dd:ba2d/1282c19:dd:c25:c25d:dd:dd:dd:ba2d
472c19:dd:c25:c25d:dd:dd:dd:ba2e/1282c19:dd:c25:c25d:dd:dd:dd:ba2e
482c19:dd:c25:c25d:dd:dd:dd:ba2f/1282c19:dd:c25:c25d:dd:dd:dd:ba2f
492c19:dd:c25:c25d:dd:dd:dd:ba30/1282c19:dd:c25:c25d:dd:dd:dd:ba30
502c19:dd:c25:c25d:dd:dd:dd:ba31/1282c19:dd:c25:c25d:dd:dd:dd:ba31
512c19:dd:c25:c25d:dd:dd:dd:ba32/1282c19:dd:c25:c25d:dd:dd:dd:ba32
522c19:dd:c25:c25d:dd:dd:dd:ba33/1282c19:dd:c25:c25d:dd:dd:dd:ba33
532c19:dd:c25:c25d:dd:dd:dd:ba34/1282c19:dd:c25:c25d:dd:dd:dd:ba34
542c19:dd:c25:c25d:dd:dd:dd:ba35/1282c19:dd:c25:c25d:dd:dd:dd:ba35
552c19:dd:c25:c25d:dd:dd:dd:ba36/1282c19:dd:c25:c25d:dd:dd:dd:ba36
562c19:dd:c25:c25d:dd:dd:dd:ba37/1282c19:dd:c25:c25d:dd:dd:dd:ba37
572c19:dd:c25:c25d:dd:dd:dd:ba38/1282c19:dd:c25:c25d:dd:dd:dd:ba38
582c19:dd:c25:c25d:dd:dd:dd:ba39/1282c19:dd:c25:c25d:dd:dd:dd:ba39
592c19:dd:c25:c25d:dd:dd:dd:ba3a/1282c19:dd:c25:c25d:dd:dd:dd:ba3a
602c19:dd:c25:c25d:dd:dd:dd:ba3b/1282c19:dd:c25:c25d:dd:dd:dd:ba3b
612c19:dd:c25:c25d:dd:dd:dd:ba3c/1282c19:dd:c25:c25d:dd:dd:dd:ba3c
622c19:dd:c25:c25d:dd:dd:dd:ba3d/1282c19:dd:c25:c25d:dd:dd:dd:ba3d
632c19:dd:c25:c25d:dd:dd:dd:ba3e/1282c19:dd:c25:c25d:dd:dd:dd:ba3e
642c19:dd:c25:c25d:dd:dd:dd:ba3f/1282c19:dd:c25:c25d:dd:dd:dd:ba3f
652c19:dd:c25:c25d:dd:dd:dd:ba40/1282c19:dd:c25:c25d:dd:dd:dd:ba40
662c19:dd:c25:c25d:dd:dd:dd:ba41/1282c19:dd:c25:c25d:dd:dd:dd:ba41
672c19:dd:c25:c25d:dd:dd:dd:ba42/1282c19:dd:c25:c25d:dd:dd:dd:ba42
682c19:dd:c25:c25d:dd:dd:dd:ba43/1282c19:dd:c25:c25d:dd:dd:dd:ba43
692c19:dd:c25:c25d:dd:dd:dd:ba44/1282c19:dd:c25:c25d:dd:dd:dd:ba44
702c19:dd:c25:c25d:dd:dd:dd:ba45/1282c19:dd:c25:c25d:dd:dd:dd:ba45
712c19:dd:c25:c25d:dd:dd:dd:ba46/1282c19:dd:c25:c25d:dd:dd:dd:ba46
722c19:dd:c25:c25d:dd:dd:dd:ba47/1282c19:dd:c25:c25d:dd:dd:dd:ba47
732c19:dd:c25:c25d:dd:dd:dd:ba48/1282c19:dd:c25:c25d:dd:dd:dd:ba48
742c19:dd:c25:c25d:dd:dd:dd:ba49/1282c19:dd:c25:c25d:dd:dd:dd:ba49
752c19:dd:c25:c25d:dd:dd:dd:ba4a/1282c19:dd:c25:c25d:dd:dd:dd:ba4a
762c19:dd:c25:c25d:dd:dd:dd:ba4b/1282c19:dd:c25:c25d:dd:dd:dd:ba4b
772c19:dd:c25:c25d:dd:dd:dd:ba4c/1282c19:dd:c25:c25d:dd:dd:dd:ba4c
782c19:dd:c25:c25d:dd:dd:dd:ba4d/1282c19:dd:c25:c25d:dd:dd:dd:ba4d
792c19:dd:c25:c25d:dd:dd:dd:ba4e/1282c19:dd:c25:c25d:dd:dd:dd:ba4e
802c19:dd:c25:c25d:dd:dd:dd:ba4f/1282c19:dd:c25:c25d:dd:dd:dd:ba4f
812c19:dd:c25:c25d:dd:dd:dd:ba50/1282c19:dd:c25:c25d:dd:dd:dd:ba50
822c19:dd:c25:c25d:dd:dd:dd:ba51/1282c19:dd:c25:c25d:dd:dd:dd:ba51
832c19:dd:c25:c25d:dd:dd:dd:ba52/1282c19:dd:c25:c25d:dd:dd:dd:ba52
842c19:dd:c25:c25d:dd:dd:dd:ba53/1282c19:dd:c25:c25d:dd:dd:dd:ba53
852c19:dd:c25:c25d:dd:dd:dd:ba54/1282c19:dd:c25:c25d:dd:dd:dd:ba54
862c19:dd:c25:c25d:dd:dd:dd:ba55/1282c19:dd:c25:c25d:dd:dd:dd:ba55
872c19:dd:c25:c25d:dd:dd:dd:ba56/1282c19:dd:c25:c25d:dd:dd:dd:ba56
882c19:dd:c25:c25d:dd:dd:dd:ba57/1282c19:dd:c25:c25d:dd:dd:dd:ba57
892c19:dd:c25:c25d:dd:dd:dd:ba58/1282c19:dd:c25:c25d:dd:dd:dd:ba58
902c19:dd:c25:c25d:dd:dd:dd:ba59/1282c19:dd:c25:c25d:dd:dd:dd:ba59
912c19:dd:c25:c25d:dd:dd:dd:ba5a/1282c19:dd:c25:c25d:dd:dd:dd:ba5a
922c19:dd:c25:c25d:dd:dd:dd:ba5b/1282c19:dd:c25:c25d:dd:dd:dd:ba5b
932c19:dd:c25:c25d:dd:dd:dd:ba5c/1282c19:dd:c25:c25d:dd:dd:dd:ba5c
942c19:dd:c25:c25d:dd:dd:dd:ba5d/1282c19:dd:c25:c25d:dd:dd:dd:ba5d
952c19:dd:c25:c25d:dd:dd:dd:ba5e/1282c19:dd:c25:c25d:dd:dd:dd:ba5e
962c19:dd:c25:c25d:dd:dd:dd:ba5f/1282c19:dd:c25:c25d:dd:dd:dd:ba5f
972c19:dd:c25:c25d:dd:dd:dd:ba60/1282c19:dd:c25:c25d:dd:dd:dd:ba60
982c19:dd:c25:c25d:dd:dd:dd:ba61/1282c19:dd:c25:c25d:dd:dd:dd:ba61
992c19:dd:c25:c25d:dd:dd:dd:ba62/1282c19:dd:c25:c25d:dd:dd:dd:ba62
1002c19:dd:c25:c25d:dd:dd:dd:ba63/1282c19:dd:c25:c25d:dd:dd:dd:ba63
1012c19:dd:c25:c25d:dd:dd:dd:ba64/1282c19:dd:c25:c25d:dd:dd:dd:ba64
1022c19:dd:c25:c25d:dd:dd:dd:ba65/1282c19:dd:c25:c25d:dd:dd:dd:ba65
1032c19:dd:c25:c25d:dd:dd:dd:ba66/1282c19:dd:c25:c25d:dd:dd:dd:ba66
1042c19:dd:c25:c25d:dd:dd:dd:ba67/1282c19:dd:c25:c25d:dd:dd:dd:ba67
1052c19:dd:c25:c25d:dd:dd:dd:ba68/1282c19:dd:c25:c25d:dd:dd:dd:ba68
1062c19:dd:c25:c25d:dd:dd:dd:ba69/1282c19:dd:c25:c25d:dd:dd:dd:ba69
1072c19:dd:c25:c25d:dd:dd:dd:ba6a/1282c19:dd:c25:c25d:dd:dd:dd:ba6a
1082c19:dd:c25:c25d:dd:dd:dd:ba6b/1282c19:dd:c25:c25d:dd:dd:dd:ba6b
1092c19:dd:c25:c25d:dd:dd:dd:ba6c/1282c19:dd:c25:c25d:dd:dd:dd:ba6c
1102c19:dd:c25:c25d:dd:dd:dd:ba6d/1282c19:dd:c25:c25d:dd:dd:dd:ba6d
1112c19:dd:c25:c25d:dd:dd:dd:ba6e/1282c19:dd:c25:c25d:dd:dd:dd:ba6e
1122c19:dd:c25:c25d:dd:dd:dd:ba6f/1282c19:dd:c25:c25d:dd:dd:dd:ba6f
1132c19:dd:c25:c25d:dd:dd:dd:ba70/1282c19:dd:c25:c25d:dd:dd:dd:ba70
1142c19:dd:c25:c25d:dd:dd:dd:ba71/1282c19:dd:c25:c25d:dd:dd:dd:ba71
1152c19:dd:c25:c25d:dd:dd:dd:ba72/1282c19:dd:c25:c25d:dd:dd:dd:ba72
1162c19:dd:c25:c25d:dd:dd:dd:ba73/1282c19:dd:c25:c25d:dd:dd:dd:ba73
1172c19:dd:c25:c25d:dd:dd:dd:ba74/1282c19:dd:c25:c25d:dd:dd:dd:ba74
1182c19:dd:c25:c25d:dd:dd:dd:ba75/1282c19:dd:c25:c25d:dd:dd:dd:ba75
1192c19:dd:c25:c25d:dd:dd:dd:ba76/1282c19:dd:c25:c25d:dd:dd:dd:ba76
1202c19:dd:c25:c25d:dd:dd:dd:ba77/1282c19:dd:c25:c25d:dd:dd:dd:ba77
1212c19:dd:c25:c25d:dd:dd:dd:ba78/1282c19:dd:c25:c25d:dd:dd:dd:ba78
1222c19:dd:c25:c25d:dd:dd:dd:ba79/1282c19:dd:c25:c25d:dd:dd:dd:ba79
1232c19:dd:c25:c25d:dd:dd:dd:ba7a/1282c19:dd:c25:c25d:dd:dd:dd:ba7a
1242c19:dd:c25:c25d:dd:dd:dd:ba7b/1282c19:dd:c25:c25d:dd:dd:dd:ba7b
1252c19:dd:c25:c25d:dd:dd:dd:ba7c/1282c19:dd:c25:c25d:dd:dd:dd:ba7c
1262c19:dd:c25:c25d:dd:dd:dd:ba7d/1282c19:dd:c25:c25d:dd:dd:dd:ba7d
1272c19:dd:c25:c25d:dd:dd:dd:ba7e/1282c19:dd:c25:c25d:dd:dd:dd:ba7e
1282c19:dd:c25:c25d:dd:dd:dd:ba7f/1282c19:dd:c25:c25d:dd:dd:dd:ba7f
1292c19:dd:c25:c25d:dd:dd:dd:ba80/1282c19:dd:c25:c25d:dd:dd:dd:ba80
1302c19:dd:c25:c25d:dd:dd:dd:ba81/1282c19:dd:c25:c25d:dd:dd:dd:ba81
1312c19:dd:c25:c25d:dd:dd:dd:ba82/1282c19:dd:c25:c25d:dd:dd:dd:ba82
1322c19:dd:c25:c25d:dd:dd:dd:ba83/1282c19:dd:c25:c25d:dd:dd:dd:ba83
1332c19:dd:c25:c25d:dd:dd:dd:ba84/1282c19:dd:c25:c25d:dd:dd:dd:ba84
1342c19:dd:c25:c25d:dd:dd:dd:ba85/1282c19:dd:c25:c25d:dd:dd:dd:ba85
1352c19:dd:c25:c25d:dd:dd:dd:ba86/1282c19:dd:c25:c25d:dd:dd:dd:ba86
1362c19:dd:c25:c25d:dd:dd:dd:ba87/1282c19:dd:c25:c25d:dd:dd:dd:ba87
1372c19:dd:c25:c25d:dd:dd:dd:ba88/1282c19:dd:c25:c25d:dd:dd:dd:ba88
1382c19:dd:c25:c25d:dd:dd:dd:ba89/1282c19:dd:c25:c25d:dd:dd:dd:ba89
1392c19:dd:c25:c25d:dd:dd:dd:ba8a/1282c19:dd:c25:c25d:dd:dd:dd:ba8a
1402c19:dd:c25:c25d:dd:dd:dd:ba8b/1282c19:dd:c25:c25d:dd:dd:dd:ba8b
1412c19:dd:c25:c25d:dd:dd:dd:ba8c/1282c19:dd:c25:c25d:dd:dd:dd:ba8c
1422c19:dd:c25:c25d:dd:dd:dd:ba8d/1282c19:dd:c25:c25d:dd:dd:dd:ba8d
1432c19:dd:c25:c25d:dd:dd:dd:ba8e/1282c19:dd:c25:c25d:dd:dd:dd:ba8e
1442c19:dd:c25:c25d:dd:dd:dd:ba8f/1282c19:dd:c25:c25d:dd:dd:dd:ba8f
1452c19:dd:c25:c25d:dd:dd:dd:ba90/1282c19:dd:c25:c25d:dd:dd:dd:ba90
1462c19:dd:c25:c25d:dd:dd:dd:ba91/1282c19:dd:c25:c25d:dd:dd:dd:ba91
1472c19:dd:c25:c25d:dd:dd:dd:ba92/1282c19:dd:c25:c25d:dd:dd:dd:ba92
1482c19:dd:c25:c25d:dd:dd:dd:ba93/1282c19:dd:c25:c25d:dd:dd:dd:ba93
1492c19:dd:c25:c25d:dd:dd:dd:ba94/1282c19:dd:c25:c25d:dd:dd:dd:ba94
1502c19:dd:c25:c25d:dd:dd:dd:ba95/1282c19:dd:c25:c25d:dd:dd:dd:ba95
1512c19:dd:c25:c25d:dd:dd:dd:ba96/1282c19:dd:c25:c25d:dd:dd:dd:ba96
1522c19:dd:c25:c25d:dd:dd:dd:ba97/1282c19:dd:c25:c25d:dd:dd:dd:ba97
1532c19:dd:c25:c25d:dd:dd:dd:ba98/1282c19:dd:c25:c25d:dd:dd:dd:ba98
1542c19:dd:c25:c25d:dd:dd:dd:ba99/1282c19:dd:c25:c25d:dd:dd:dd:ba99
1552c19:dd:c25:c25d:dd:dd:dd:ba9a/1282c19:dd:c25:c25d:dd:dd:dd:ba9a
1562c19:dd:c25:c25d:dd:dd:dd:ba9b/1282c19:dd:c25:c25d:dd:dd:dd:ba9b
1572c19:dd:c25:c25d:dd:dd:dd:ba9c/1282c19:dd:c25:c25d:dd:dd:dd:ba9c
1582c19:dd:c25:c25d:dd:dd:dd:ba9d/1282c19:dd:c25:c25d:dd:dd:dd:ba9d
1592c19:dd:c25:c25d:dd:dd:dd:ba9e/1282c19:dd:c25:c25d:dd:dd:dd:ba9e
1602c19:dd:c25:c25d:dd:dd:dd:ba9f/1282c19:dd:c25:c25d:dd:dd:dd:ba9f
1612c19:dd:c25:c25d:dd:dd:dd:baa0/1282c19:dd:c25:c25d:dd:dd:dd:baa0
1622c19:dd:c25:c25d:dd:dd:dd:baa1/1282c19:dd:c25:c25d:dd:dd:dd:baa1
1632c19:dd:c25:c25d:dd:dd:dd:baa2/1282c19:dd:c25:c25d:dd:dd:dd:baa2
1642c19:dd:c25:c25d:dd:dd:dd:baa3/1282c19:dd:c25:c25d:dd:dd:dd:baa3
1652c19:dd:c25:c25d:dd:dd:dd:baa4/1282c19:dd:c25:c25d:dd:dd:dd:baa4
1662c19:dd:c25:c25d:dd:dd:dd:baa5/1282c19:dd:c25:c25d:dd:dd:dd:baa5
1672c19:dd:c25:c25d:dd:dd:dd:baa6/1282c19:dd:c25:c25d:dd:dd:dd:baa6
1682c19:dd:c25:c25d:dd:dd:dd:baa7/1282c19:dd:c25:c25d:dd:dd:dd:baa7
1692c19:dd:c25:c25d:dd:dd:dd:baa8/1282c19:dd:c25:c25d:dd:dd:dd:baa8
1702c19:dd:c25:c25d:dd:dd:dd:baa9/1282c19:dd:c25:c25d:dd:dd:dd:baa9
1712c19:dd:c25:c25d:dd:dd:dd:baaa/1282c19:dd:c25:c25d:dd:dd:dd:baaa
1722c19:dd:c25:c25d:dd:dd:dd:baab/1282c19:dd:c25:c25d:dd:dd:dd:baab
1732c19:dd:c25:c25d:dd:dd:dd:baac/1282c19:dd:c25:c25d:dd:dd:dd:baac
1742c19:dd:c25:c25d:dd:dd:dd:baad/1282c19:dd:c25:c25d:dd:dd:dd:baad
1752c19:dd:c25:c25d:dd:dd:dd:baae/1282c19:dd:c25:c25d:dd:dd:dd:baae
1762c19:dd:c25:c25d:dd:dd:dd:baaf/1282c19:dd:c25:c25d:dd:dd:dd:baaf
1772c19:dd:c25:c25d:dd:dd:dd:bab0/1282c19:dd:c25:c25d:dd:dd:dd:bab0
1782c19:dd:c25:c25d:dd:dd:dd:bab1/1282c19:dd:c25:c25d:dd:dd:dd:bab1
1792c19:dd:c25:c25d:dd:dd:dd:bab2/1282c19:dd:c25:c25d:dd:dd:dd:bab2
1802c19:dd:c25:c25d:dd:dd:dd:bab3/1282c19:dd:c25:c25d:dd:dd:dd:bab3
1812c19:dd:c25:c25d:dd:dd:dd:bab4/1282c19:dd:c25:c25d:dd:dd:dd:bab4
1822c19:dd:c25:c25d:dd:dd:dd:bab5/1282c19:dd:c25:c25d:dd:dd:dd:bab5
1832c19:dd:c25:c25d:dd:dd:dd:bab6/1282c19:dd:c25:c25d:dd:dd:dd:bab6
1842c19:dd:c25:c25d:dd:dd:dd:bab7/1282c19:dd:c25:c25d:dd:dd:dd:bab7
1852c19:dd:c25:c25d:dd:dd:dd:bab8/1282c19:dd:c25:c25d:dd:dd:dd:bab8
1862c19:dd:c25:c25d:dd:dd:dd:bab9/1282c19:dd:c25:c25d:dd:dd:dd:bab9
1872c19:dd:c25:c25d:dd:dd:dd:baba/1282c19:dd:c25:c25d:dd:dd:dd:baba
1882c19:dd:c25:c25d:dd:dd:dd:babb/1282c19:dd:c25:c25d:dd:dd:dd:babb
1892c19:dd:c25:c25d:dd:dd:dd:babc/1282c19:dd:c25:c25d:dd:dd:dd:babc
1902c19:dd:c25:c25d:dd:dd:dd:babd/1282c19:dd:c25:c25d:dd:dd:dd:babd
1912c19:dd:c25:c25d:dd:dd:dd:babe/1282c19:dd:c25:c25d:dd:dd:dd:babe
1922c19:dd:c25:c25d:dd:dd:dd:babf/1282c19:dd:c25:c25d:dd:dd:dd:babf
1932c19:dd:c25:c25d:dd:dd:dd:bac0/1282c19:dd:c25:c25d:dd:dd:dd:bac0
1942c19:dd:c25:c25d:dd:dd:dd:bac1/1282c19:dd:c25:c25d:dd:dd:dd:bac1
1952c19:dd:c25:c25d:dd:dd:dd:bac2/1282c19:dd:c25:c25d:dd:dd:dd:bac2
1962c19:dd:c25:c25d:dd:dd:dd:bac3/1282c19:dd:c25:c25d:dd:dd:dd:bac3
1972c19:dd:c25:c25d:dd:dd:dd:bac4/1282c19:dd:c25:c25d:dd:dd:dd:bac4
1982c19:dd:c25:c25d:dd:dd:dd:bac5/1282c19:dd:c25:c25d:dd:dd:dd:bac5
1992c19:dd:c25:c25d:dd:dd:dd:bac6/1282c19:dd:c25:c25d:dd:dd:dd:bac6
2002c19:dd:c25:c25d:dd:dd:dd:bac7/1282c19:dd:c25:c25d:dd:dd:dd:bac7
2012c19:dd:c25:c25d:dd:dd:dd:bac8/1282c19:dd:c25:c25d:dd:dd:dd:bac8
2022c19:dd:c25:c25d:dd:dd:dd:bac9/1282c19:dd:c25:c25d:dd:dd:dd:bac9
2032c19:dd:c25:c25d:dd:dd:dd:baca/1282c19:dd:c25:c25d:dd:dd:dd:baca
2042c19:dd:c25:c25d:dd:dd:dd:bacb/1282c19:dd:c25:c25d:dd:dd:dd:bacb
2052c19:dd:c25:c25d:dd:dd:dd:bacc/1282c19:dd:c25:c25d:dd:dd:dd:bacc
2062c19:dd:c25:c25d:dd:dd:dd:bacd/1282c19:dd:c25:c25d:dd:dd:dd:bacd
2072c19:dd:c25:c25d:dd:dd:dd:bace/1282c19:dd:c25:c25d:dd:dd:dd:bace
2082c19:dd:c25:c25d:dd:dd:dd:bacf/1282c19:dd:c25:c25d:dd:dd:dd:bacf
2092c19:dd:c25:c25d:dd:dd:dd:bad0/1282c19:dd:c25:c25d:dd:dd:dd:bad0
2102c19:dd:c25:c25d:dd:dd:dd:bad1/1282c19:dd:c25:c25d:dd:dd:dd:bad1
2112c19:dd:c25:c25d:dd:dd:dd:bad2/1282c19:dd:c25:c25d:dd:dd:dd:bad2
2122c19:dd:c25:c25d:dd:dd:dd:bad3/1282c19:dd:c25:c25d:dd:dd:dd:bad3
2132c19:dd:c25:c25d:dd:dd:dd:bad4/1282c19:dd:c25:c25d:dd:dd:dd:bad4
2142c19:dd:c25:c25d:dd:dd:dd:bad5/1282c19:dd:c25:c25d:dd:dd:dd:bad5
2152c19:dd:c25:c25d:dd:dd:dd:bad6/1282c19:dd:c25:c25d:dd:dd:dd:bad6
2162c19:dd:c25:c25d:dd:dd:dd:bad7/1282c19:dd:c25:c25d:dd:dd:dd:bad7
2172c19:dd:c25:c25d:dd:dd:dd:bad8/1282c19:dd:c25:c25d:dd:dd:dd:bad8
2182c19:dd:c25:c25d:dd:dd:dd:bad9/1282c19:dd:c25:c25d:dd:dd:dd:bad9
2192c19:dd:c25:c25d:dd:dd:dd:bada/1282c19:dd:c25:c25d:dd:dd:dd:bada
2202c19:dd:c25:c25d:dd:dd:dd:badb/1282c19:dd:c25:c25d:dd:dd:dd:badb
2212c19:dd:c25:c25d:dd:dd:dd:badc/1282c19:dd:c25:c25d:dd:dd:dd:badc
2222c19:dd:c25:c25d:dd:dd:dd:badd/1282c19:dd:c25:c25d:dd:dd:dd:badd
2232c19:dd:c25:c25d:dd:dd:dd:bade/1282c19:dd:c25:c25d:dd:dd:dd:bade
2242c19:dd:c25:c25d:dd:dd:dd:badf/1282c19:dd:c25:c25d:dd:dd:dd:badf
2252c19:dd:c25:c25d:dd:dd:dd:bae0/1282c19:dd:c25:c25d:dd:dd:dd:bae0
2262c19:dd:c25:c25d:dd:dd:dd:bae1/1282c19:dd:c25:c25d:dd:dd:dd:bae1
2272c19:dd:c25:c25d:dd:dd:dd:bae2/1282c19:dd:c25:c25d:dd:dd:dd:bae2
2282c19:dd:c25:c25d:dd:dd:dd:bae3/1282c19:dd:c25:c25d:dd:dd:dd:bae3
2292c19:dd:c25:c25d:dd:dd:dd:bae4/1282c19:dd:c25:c25d:dd:dd:dd:bae4
2302c19:dd:c25:c25d:dd:dd:dd:bae5/1282c19:dd:c25:c25d:dd:dd:dd:bae5
2312c19:dd:c25:c25d:dd:dd:dd:bae6/1282c19:dd:c25:c25d:dd:dd:dd:bae6
2322c19:dd:c25:c25d:dd:dd:dd:bae7/1282c19:dd:c25:c25d:dd:dd:dd:bae7
2332c19:dd:c25:c25d:dd:dd:dd:bae8/1282c19:dd:c25:c25d:dd:dd:dd:bae8
2342c19:dd:c25:c25d:dd:dd:dd:bae9/1282c19:dd:c25:c25d:dd:dd:dd:bae9
2352c19:dd:c25:c25d:dd:dd:dd:baea/1282c19:dd:c25:c25d:dd:dd:dd:baea
2362c19:dd:c25:c25d:dd:dd:dd:baeb/1282c19:dd:c25:c25d:dd:dd:dd:baeb
2372c19:dd:c25:c25d:dd:dd:dd:baec/1282c19:dd:c25:c25d:dd:dd:dd:baec
2382c19:dd:c25:c25d:dd:dd:dd:baed/1282c19:dd:c25:c25d:dd:dd:dd:baed
2392c19:dd:c25:c25d:dd:dd:dd:baee/1282c19:dd:c25:c25d:dd:dd:dd:baee
2402c19:dd:c25:c25d:dd:dd:dd:baef/1282c19:dd:c25:c25d:dd:dd:dd:baef
2412c19:dd:c25:c25d:dd:dd:dd:baf0/1282c19:dd:c25:c25d:dd:dd:dd:baf0
2422c19:dd:c25:c25d:dd:dd:dd:baf1/1282c19:dd:c25:c25d:dd:dd:dd:baf1
2432c19:dd:c25:c25d:dd:dd:dd:baf2/1282c19:dd:c25:c25d:dd:dd:dd:baf2
2442c19:dd:c25:c25d:dd:dd:dd:baf3/1282c19:dd:c25:c25d:dd:dd:dd:baf3
2452c19:dd:c25:c25d:dd:dd:dd:baf4/1282c19:dd:c25:c25d:dd:dd:dd:baf4
2462c19:dd:c25:c25d:dd:dd:dd:baf5/1282c19:dd:c25:c25d:dd:dd:dd:baf5
2472c19:dd:c25:c25d:dd:dd:dd:baf6/1282c19:dd:c25:c25d:dd:dd:dd:baf6
2482c19:dd:c25:c25d:dd:dd:dd:baf7/1282c19:dd:c25:c25d:dd:dd:dd:baf7
2492c19:dd:c25:c25d:dd:dd:dd:baf8/1282c19:dd:c25:c25d:dd:dd:dd:baf8
2502c19:dd:c25:c25d:dd:dd:dd:baf9/1282c19:dd:c25:c25d:dd:dd:dd:baf9
2512c19:dd:c25:c25d:dd:dd:dd:bafa/1282c19:dd:c25:c25d:dd:dd:dd:bafa
2522c19:dd:c25:c25d:dd:dd:dd:bafb/1282c19:dd:c25:c25d:dd:dd:dd:bafb
2532c19:dd:c25:c25d:dd:dd:dd:bafc/1282c19:dd:c25:c25d:dd:dd:dd:bafc
2542c19:dd:c25:c25d:dd:dd:dd:bafd/1282c19:dd:c25:c25d:dd:dd:dd:bafd
2552c19:dd:c25:c25d:dd:dd:dd:bafe/1282c19:dd:c25:c25d:dd:dd:dd:bafe
2562c19:dd:c25:c25d:dd:dd:dd:baff/1282c19:dd:c25:c25d:dd:dd:dd:baff

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.