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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:d9:dd:c25:c25:d915:fa00/120
First address
2c19:dd:d9:dd:c25:c25:d915:fa00
Last address
2c19:dd:d9:dd:c25:c25:d915:faff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:fa00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
a.f.5.1.9.d.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.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:d9:dd:c25:c25:d915:fa00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:fa00/1282c19:dd:d9:dd:c25:c25:d915:fa00
22c19:dd:d9:dd:c25:c25:d915:fa01/1282c19:dd:d9:dd:c25:c25:d915:fa01
32c19:dd:d9:dd:c25:c25:d915:fa02/1282c19:dd:d9:dd:c25:c25:d915:fa02
42c19:dd:d9:dd:c25:c25:d915:fa03/1282c19:dd:d9:dd:c25:c25:d915:fa03
52c19:dd:d9:dd:c25:c25:d915:fa04/1282c19:dd:d9:dd:c25:c25:d915:fa04
62c19:dd:d9:dd:c25:c25:d915:fa05/1282c19:dd:d9:dd:c25:c25:d915:fa05
72c19:dd:d9:dd:c25:c25:d915:fa06/1282c19:dd:d9:dd:c25:c25:d915:fa06
82c19:dd:d9:dd:c25:c25:d915:fa07/1282c19:dd:d9:dd:c25:c25:d915:fa07
92c19:dd:d9:dd:c25:c25:d915:fa08/1282c19:dd:d9:dd:c25:c25:d915:fa08
102c19:dd:d9:dd:c25:c25:d915:fa09/1282c19:dd:d9:dd:c25:c25:d915:fa09
112c19:dd:d9:dd:c25:c25:d915:fa0a/1282c19:dd:d9:dd:c25:c25:d915:fa0a
122c19:dd:d9:dd:c25:c25:d915:fa0b/1282c19:dd:d9:dd:c25:c25:d915:fa0b
132c19:dd:d9:dd:c25:c25:d915:fa0c/1282c19:dd:d9:dd:c25:c25:d915:fa0c
142c19:dd:d9:dd:c25:c25:d915:fa0d/1282c19:dd:d9:dd:c25:c25:d915:fa0d
152c19:dd:d9:dd:c25:c25:d915:fa0e/1282c19:dd:d9:dd:c25:c25:d915:fa0e
162c19:dd:d9:dd:c25:c25:d915:fa0f/1282c19:dd:d9:dd:c25:c25:d915:fa0f
172c19:dd:d9:dd:c25:c25:d915:fa10/1282c19:dd:d9:dd:c25:c25:d915:fa10
182c19:dd:d9:dd:c25:c25:d915:fa11/1282c19:dd:d9:dd:c25:c25:d915:fa11
192c19:dd:d9:dd:c25:c25:d915:fa12/1282c19:dd:d9:dd:c25:c25:d915:fa12
202c19:dd:d9:dd:c25:c25:d915:fa13/1282c19:dd:d9:dd:c25:c25:d915:fa13
212c19:dd:d9:dd:c25:c25:d915:fa14/1282c19:dd:d9:dd:c25:c25:d915:fa14
222c19:dd:d9:dd:c25:c25:d915:fa15/1282c19:dd:d9:dd:c25:c25:d915:fa15
232c19:dd:d9:dd:c25:c25:d915:fa16/1282c19:dd:d9:dd:c25:c25:d915:fa16
242c19:dd:d9:dd:c25:c25:d915:fa17/1282c19:dd:d9:dd:c25:c25:d915:fa17
252c19:dd:d9:dd:c25:c25:d915:fa18/1282c19:dd:d9:dd:c25:c25:d915:fa18
262c19:dd:d9:dd:c25:c25:d915:fa19/1282c19:dd:d9:dd:c25:c25:d915:fa19
272c19:dd:d9:dd:c25:c25:d915:fa1a/1282c19:dd:d9:dd:c25:c25:d915:fa1a
282c19:dd:d9:dd:c25:c25:d915:fa1b/1282c19:dd:d9:dd:c25:c25:d915:fa1b
292c19:dd:d9:dd:c25:c25:d915:fa1c/1282c19:dd:d9:dd:c25:c25:d915:fa1c
302c19:dd:d9:dd:c25:c25:d915:fa1d/1282c19:dd:d9:dd:c25:c25:d915:fa1d
312c19:dd:d9:dd:c25:c25:d915:fa1e/1282c19:dd:d9:dd:c25:c25:d915:fa1e
322c19:dd:d9:dd:c25:c25:d915:fa1f/1282c19:dd:d9:dd:c25:c25:d915:fa1f
332c19:dd:d9:dd:c25:c25:d915:fa20/1282c19:dd:d9:dd:c25:c25:d915:fa20
342c19:dd:d9:dd:c25:c25:d915:fa21/1282c19:dd:d9:dd:c25:c25:d915:fa21
352c19:dd:d9:dd:c25:c25:d915:fa22/1282c19:dd:d9:dd:c25:c25:d915:fa22
362c19:dd:d9:dd:c25:c25:d915:fa23/1282c19:dd:d9:dd:c25:c25:d915:fa23
372c19:dd:d9:dd:c25:c25:d915:fa24/1282c19:dd:d9:dd:c25:c25:d915:fa24
382c19:dd:d9:dd:c25:c25:d915:fa25/1282c19:dd:d9:dd:c25:c25:d915:fa25
392c19:dd:d9:dd:c25:c25:d915:fa26/1282c19:dd:d9:dd:c25:c25:d915:fa26
402c19:dd:d9:dd:c25:c25:d915:fa27/1282c19:dd:d9:dd:c25:c25:d915:fa27
412c19:dd:d9:dd:c25:c25:d915:fa28/1282c19:dd:d9:dd:c25:c25:d915:fa28
422c19:dd:d9:dd:c25:c25:d915:fa29/1282c19:dd:d9:dd:c25:c25:d915:fa29
432c19:dd:d9:dd:c25:c25:d915:fa2a/1282c19:dd:d9:dd:c25:c25:d915:fa2a
442c19:dd:d9:dd:c25:c25:d915:fa2b/1282c19:dd:d9:dd:c25:c25:d915:fa2b
452c19:dd:d9:dd:c25:c25:d915:fa2c/1282c19:dd:d9:dd:c25:c25:d915:fa2c
462c19:dd:d9:dd:c25:c25:d915:fa2d/1282c19:dd:d9:dd:c25:c25:d915:fa2d
472c19:dd:d9:dd:c25:c25:d915:fa2e/1282c19:dd:d9:dd:c25:c25:d915:fa2e
482c19:dd:d9:dd:c25:c25:d915:fa2f/1282c19:dd:d9:dd:c25:c25:d915:fa2f
492c19:dd:d9:dd:c25:c25:d915:fa30/1282c19:dd:d9:dd:c25:c25:d915:fa30
502c19:dd:d9:dd:c25:c25:d915:fa31/1282c19:dd:d9:dd:c25:c25:d915:fa31
512c19:dd:d9:dd:c25:c25:d915:fa32/1282c19:dd:d9:dd:c25:c25:d915:fa32
522c19:dd:d9:dd:c25:c25:d915:fa33/1282c19:dd:d9:dd:c25:c25:d915:fa33
532c19:dd:d9:dd:c25:c25:d915:fa34/1282c19:dd:d9:dd:c25:c25:d915:fa34
542c19:dd:d9:dd:c25:c25:d915:fa35/1282c19:dd:d9:dd:c25:c25:d915:fa35
552c19:dd:d9:dd:c25:c25:d915:fa36/1282c19:dd:d9:dd:c25:c25:d915:fa36
562c19:dd:d9:dd:c25:c25:d915:fa37/1282c19:dd:d9:dd:c25:c25:d915:fa37
572c19:dd:d9:dd:c25:c25:d915:fa38/1282c19:dd:d9:dd:c25:c25:d915:fa38
582c19:dd:d9:dd:c25:c25:d915:fa39/1282c19:dd:d9:dd:c25:c25:d915:fa39
592c19:dd:d9:dd:c25:c25:d915:fa3a/1282c19:dd:d9:dd:c25:c25:d915:fa3a
602c19:dd:d9:dd:c25:c25:d915:fa3b/1282c19:dd:d9:dd:c25:c25:d915:fa3b
612c19:dd:d9:dd:c25:c25:d915:fa3c/1282c19:dd:d9:dd:c25:c25:d915:fa3c
622c19:dd:d9:dd:c25:c25:d915:fa3d/1282c19:dd:d9:dd:c25:c25:d915:fa3d
632c19:dd:d9:dd:c25:c25:d915:fa3e/1282c19:dd:d9:dd:c25:c25:d915:fa3e
642c19:dd:d9:dd:c25:c25:d915:fa3f/1282c19:dd:d9:dd:c25:c25:d915:fa3f
652c19:dd:d9:dd:c25:c25:d915:fa40/1282c19:dd:d9:dd:c25:c25:d915:fa40
662c19:dd:d9:dd:c25:c25:d915:fa41/1282c19:dd:d9:dd:c25:c25:d915:fa41
672c19:dd:d9:dd:c25:c25:d915:fa42/1282c19:dd:d9:dd:c25:c25:d915:fa42
682c19:dd:d9:dd:c25:c25:d915:fa43/1282c19:dd:d9:dd:c25:c25:d915:fa43
692c19:dd:d9:dd:c25:c25:d915:fa44/1282c19:dd:d9:dd:c25:c25:d915:fa44
702c19:dd:d9:dd:c25:c25:d915:fa45/1282c19:dd:d9:dd:c25:c25:d915:fa45
712c19:dd:d9:dd:c25:c25:d915:fa46/1282c19:dd:d9:dd:c25:c25:d915:fa46
722c19:dd:d9:dd:c25:c25:d915:fa47/1282c19:dd:d9:dd:c25:c25:d915:fa47
732c19:dd:d9:dd:c25:c25:d915:fa48/1282c19:dd:d9:dd:c25:c25:d915:fa48
742c19:dd:d9:dd:c25:c25:d915:fa49/1282c19:dd:d9:dd:c25:c25:d915:fa49
752c19:dd:d9:dd:c25:c25:d915:fa4a/1282c19:dd:d9:dd:c25:c25:d915:fa4a
762c19:dd:d9:dd:c25:c25:d915:fa4b/1282c19:dd:d9:dd:c25:c25:d915:fa4b
772c19:dd:d9:dd:c25:c25:d915:fa4c/1282c19:dd:d9:dd:c25:c25:d915:fa4c
782c19:dd:d9:dd:c25:c25:d915:fa4d/1282c19:dd:d9:dd:c25:c25:d915:fa4d
792c19:dd:d9:dd:c25:c25:d915:fa4e/1282c19:dd:d9:dd:c25:c25:d915:fa4e
802c19:dd:d9:dd:c25:c25:d915:fa4f/1282c19:dd:d9:dd:c25:c25:d915:fa4f
812c19:dd:d9:dd:c25:c25:d915:fa50/1282c19:dd:d9:dd:c25:c25:d915:fa50
822c19:dd:d9:dd:c25:c25:d915:fa51/1282c19:dd:d9:dd:c25:c25:d915:fa51
832c19:dd:d9:dd:c25:c25:d915:fa52/1282c19:dd:d9:dd:c25:c25:d915:fa52
842c19:dd:d9:dd:c25:c25:d915:fa53/1282c19:dd:d9:dd:c25:c25:d915:fa53
852c19:dd:d9:dd:c25:c25:d915:fa54/1282c19:dd:d9:dd:c25:c25:d915:fa54
862c19:dd:d9:dd:c25:c25:d915:fa55/1282c19:dd:d9:dd:c25:c25:d915:fa55
872c19:dd:d9:dd:c25:c25:d915:fa56/1282c19:dd:d9:dd:c25:c25:d915:fa56
882c19:dd:d9:dd:c25:c25:d915:fa57/1282c19:dd:d9:dd:c25:c25:d915:fa57
892c19:dd:d9:dd:c25:c25:d915:fa58/1282c19:dd:d9:dd:c25:c25:d915:fa58
902c19:dd:d9:dd:c25:c25:d915:fa59/1282c19:dd:d9:dd:c25:c25:d915:fa59
912c19:dd:d9:dd:c25:c25:d915:fa5a/1282c19:dd:d9:dd:c25:c25:d915:fa5a
922c19:dd:d9:dd:c25:c25:d915:fa5b/1282c19:dd:d9:dd:c25:c25:d915:fa5b
932c19:dd:d9:dd:c25:c25:d915:fa5c/1282c19:dd:d9:dd:c25:c25:d915:fa5c
942c19:dd:d9:dd:c25:c25:d915:fa5d/1282c19:dd:d9:dd:c25:c25:d915:fa5d
952c19:dd:d9:dd:c25:c25:d915:fa5e/1282c19:dd:d9:dd:c25:c25:d915:fa5e
962c19:dd:d9:dd:c25:c25:d915:fa5f/1282c19:dd:d9:dd:c25:c25:d915:fa5f
972c19:dd:d9:dd:c25:c25:d915:fa60/1282c19:dd:d9:dd:c25:c25:d915:fa60
982c19:dd:d9:dd:c25:c25:d915:fa61/1282c19:dd:d9:dd:c25:c25:d915:fa61
992c19:dd:d9:dd:c25:c25:d915:fa62/1282c19:dd:d9:dd:c25:c25:d915:fa62
1002c19:dd:d9:dd:c25:c25:d915:fa63/1282c19:dd:d9:dd:c25:c25:d915:fa63
1012c19:dd:d9:dd:c25:c25:d915:fa64/1282c19:dd:d9:dd:c25:c25:d915:fa64
1022c19:dd:d9:dd:c25:c25:d915:fa65/1282c19:dd:d9:dd:c25:c25:d915:fa65
1032c19:dd:d9:dd:c25:c25:d915:fa66/1282c19:dd:d9:dd:c25:c25:d915:fa66
1042c19:dd:d9:dd:c25:c25:d915:fa67/1282c19:dd:d9:dd:c25:c25:d915:fa67
1052c19:dd:d9:dd:c25:c25:d915:fa68/1282c19:dd:d9:dd:c25:c25:d915:fa68
1062c19:dd:d9:dd:c25:c25:d915:fa69/1282c19:dd:d9:dd:c25:c25:d915:fa69
1072c19:dd:d9:dd:c25:c25:d915:fa6a/1282c19:dd:d9:dd:c25:c25:d915:fa6a
1082c19:dd:d9:dd:c25:c25:d915:fa6b/1282c19:dd:d9:dd:c25:c25:d915:fa6b
1092c19:dd:d9:dd:c25:c25:d915:fa6c/1282c19:dd:d9:dd:c25:c25:d915:fa6c
1102c19:dd:d9:dd:c25:c25:d915:fa6d/1282c19:dd:d9:dd:c25:c25:d915:fa6d
1112c19:dd:d9:dd:c25:c25:d915:fa6e/1282c19:dd:d9:dd:c25:c25:d915:fa6e
1122c19:dd:d9:dd:c25:c25:d915:fa6f/1282c19:dd:d9:dd:c25:c25:d915:fa6f
1132c19:dd:d9:dd:c25:c25:d915:fa70/1282c19:dd:d9:dd:c25:c25:d915:fa70
1142c19:dd:d9:dd:c25:c25:d915:fa71/1282c19:dd:d9:dd:c25:c25:d915:fa71
1152c19:dd:d9:dd:c25:c25:d915:fa72/1282c19:dd:d9:dd:c25:c25:d915:fa72
1162c19:dd:d9:dd:c25:c25:d915:fa73/1282c19:dd:d9:dd:c25:c25:d915:fa73
1172c19:dd:d9:dd:c25:c25:d915:fa74/1282c19:dd:d9:dd:c25:c25:d915:fa74
1182c19:dd:d9:dd:c25:c25:d915:fa75/1282c19:dd:d9:dd:c25:c25:d915:fa75
1192c19:dd:d9:dd:c25:c25:d915:fa76/1282c19:dd:d9:dd:c25:c25:d915:fa76
1202c19:dd:d9:dd:c25:c25:d915:fa77/1282c19:dd:d9:dd:c25:c25:d915:fa77
1212c19:dd:d9:dd:c25:c25:d915:fa78/1282c19:dd:d9:dd:c25:c25:d915:fa78
1222c19:dd:d9:dd:c25:c25:d915:fa79/1282c19:dd:d9:dd:c25:c25:d915:fa79
1232c19:dd:d9:dd:c25:c25:d915:fa7a/1282c19:dd:d9:dd:c25:c25:d915:fa7a
1242c19:dd:d9:dd:c25:c25:d915:fa7b/1282c19:dd:d9:dd:c25:c25:d915:fa7b
1252c19:dd:d9:dd:c25:c25:d915:fa7c/1282c19:dd:d9:dd:c25:c25:d915:fa7c
1262c19:dd:d9:dd:c25:c25:d915:fa7d/1282c19:dd:d9:dd:c25:c25:d915:fa7d
1272c19:dd:d9:dd:c25:c25:d915:fa7e/1282c19:dd:d9:dd:c25:c25:d915:fa7e
1282c19:dd:d9:dd:c25:c25:d915:fa7f/1282c19:dd:d9:dd:c25:c25:d915:fa7f
1292c19:dd:d9:dd:c25:c25:d915:fa80/1282c19:dd:d9:dd:c25:c25:d915:fa80
1302c19:dd:d9:dd:c25:c25:d915:fa81/1282c19:dd:d9:dd:c25:c25:d915:fa81
1312c19:dd:d9:dd:c25:c25:d915:fa82/1282c19:dd:d9:dd:c25:c25:d915:fa82
1322c19:dd:d9:dd:c25:c25:d915:fa83/1282c19:dd:d9:dd:c25:c25:d915:fa83
1332c19:dd:d9:dd:c25:c25:d915:fa84/1282c19:dd:d9:dd:c25:c25:d915:fa84
1342c19:dd:d9:dd:c25:c25:d915:fa85/1282c19:dd:d9:dd:c25:c25:d915:fa85
1352c19:dd:d9:dd:c25:c25:d915:fa86/1282c19:dd:d9:dd:c25:c25:d915:fa86
1362c19:dd:d9:dd:c25:c25:d915:fa87/1282c19:dd:d9:dd:c25:c25:d915:fa87
1372c19:dd:d9:dd:c25:c25:d915:fa88/1282c19:dd:d9:dd:c25:c25:d915:fa88
1382c19:dd:d9:dd:c25:c25:d915:fa89/1282c19:dd:d9:dd:c25:c25:d915:fa89
1392c19:dd:d9:dd:c25:c25:d915:fa8a/1282c19:dd:d9:dd:c25:c25:d915:fa8a
1402c19:dd:d9:dd:c25:c25:d915:fa8b/1282c19:dd:d9:dd:c25:c25:d915:fa8b
1412c19:dd:d9:dd:c25:c25:d915:fa8c/1282c19:dd:d9:dd:c25:c25:d915:fa8c
1422c19:dd:d9:dd:c25:c25:d915:fa8d/1282c19:dd:d9:dd:c25:c25:d915:fa8d
1432c19:dd:d9:dd:c25:c25:d915:fa8e/1282c19:dd:d9:dd:c25:c25:d915:fa8e
1442c19:dd:d9:dd:c25:c25:d915:fa8f/1282c19:dd:d9:dd:c25:c25:d915:fa8f
1452c19:dd:d9:dd:c25:c25:d915:fa90/1282c19:dd:d9:dd:c25:c25:d915:fa90
1462c19:dd:d9:dd:c25:c25:d915:fa91/1282c19:dd:d9:dd:c25:c25:d915:fa91
1472c19:dd:d9:dd:c25:c25:d915:fa92/1282c19:dd:d9:dd:c25:c25:d915:fa92
1482c19:dd:d9:dd:c25:c25:d915:fa93/1282c19:dd:d9:dd:c25:c25:d915:fa93
1492c19:dd:d9:dd:c25:c25:d915:fa94/1282c19:dd:d9:dd:c25:c25:d915:fa94
1502c19:dd:d9:dd:c25:c25:d915:fa95/1282c19:dd:d9:dd:c25:c25:d915:fa95
1512c19:dd:d9:dd:c25:c25:d915:fa96/1282c19:dd:d9:dd:c25:c25:d915:fa96
1522c19:dd:d9:dd:c25:c25:d915:fa97/1282c19:dd:d9:dd:c25:c25:d915:fa97
1532c19:dd:d9:dd:c25:c25:d915:fa98/1282c19:dd:d9:dd:c25:c25:d915:fa98
1542c19:dd:d9:dd:c25:c25:d915:fa99/1282c19:dd:d9:dd:c25:c25:d915:fa99
1552c19:dd:d9:dd:c25:c25:d915:fa9a/1282c19:dd:d9:dd:c25:c25:d915:fa9a
1562c19:dd:d9:dd:c25:c25:d915:fa9b/1282c19:dd:d9:dd:c25:c25:d915:fa9b
1572c19:dd:d9:dd:c25:c25:d915:fa9c/1282c19:dd:d9:dd:c25:c25:d915:fa9c
1582c19:dd:d9:dd:c25:c25:d915:fa9d/1282c19:dd:d9:dd:c25:c25:d915:fa9d
1592c19:dd:d9:dd:c25:c25:d915:fa9e/1282c19:dd:d9:dd:c25:c25:d915:fa9e
1602c19:dd:d9:dd:c25:c25:d915:fa9f/1282c19:dd:d9:dd:c25:c25:d915:fa9f
1612c19:dd:d9:dd:c25:c25:d915:faa0/1282c19:dd:d9:dd:c25:c25:d915:faa0
1622c19:dd:d9:dd:c25:c25:d915:faa1/1282c19:dd:d9:dd:c25:c25:d915:faa1
1632c19:dd:d9:dd:c25:c25:d915:faa2/1282c19:dd:d9:dd:c25:c25:d915:faa2
1642c19:dd:d9:dd:c25:c25:d915:faa3/1282c19:dd:d9:dd:c25:c25:d915:faa3
1652c19:dd:d9:dd:c25:c25:d915:faa4/1282c19:dd:d9:dd:c25:c25:d915:faa4
1662c19:dd:d9:dd:c25:c25:d915:faa5/1282c19:dd:d9:dd:c25:c25:d915:faa5
1672c19:dd:d9:dd:c25:c25:d915:faa6/1282c19:dd:d9:dd:c25:c25:d915:faa6
1682c19:dd:d9:dd:c25:c25:d915:faa7/1282c19:dd:d9:dd:c25:c25:d915:faa7
1692c19:dd:d9:dd:c25:c25:d915:faa8/1282c19:dd:d9:dd:c25:c25:d915:faa8
1702c19:dd:d9:dd:c25:c25:d915:faa9/1282c19:dd:d9:dd:c25:c25:d915:faa9
1712c19:dd:d9:dd:c25:c25:d915:faaa/1282c19:dd:d9:dd:c25:c25:d915:faaa
1722c19:dd:d9:dd:c25:c25:d915:faab/1282c19:dd:d9:dd:c25:c25:d915:faab
1732c19:dd:d9:dd:c25:c25:d915:faac/1282c19:dd:d9:dd:c25:c25:d915:faac
1742c19:dd:d9:dd:c25:c25:d915:faad/1282c19:dd:d9:dd:c25:c25:d915:faad
1752c19:dd:d9:dd:c25:c25:d915:faae/1282c19:dd:d9:dd:c25:c25:d915:faae
1762c19:dd:d9:dd:c25:c25:d915:faaf/1282c19:dd:d9:dd:c25:c25:d915:faaf
1772c19:dd:d9:dd:c25:c25:d915:fab0/1282c19:dd:d9:dd:c25:c25:d915:fab0
1782c19:dd:d9:dd:c25:c25:d915:fab1/1282c19:dd:d9:dd:c25:c25:d915:fab1
1792c19:dd:d9:dd:c25:c25:d915:fab2/1282c19:dd:d9:dd:c25:c25:d915:fab2
1802c19:dd:d9:dd:c25:c25:d915:fab3/1282c19:dd:d9:dd:c25:c25:d915:fab3
1812c19:dd:d9:dd:c25:c25:d915:fab4/1282c19:dd:d9:dd:c25:c25:d915:fab4
1822c19:dd:d9:dd:c25:c25:d915:fab5/1282c19:dd:d9:dd:c25:c25:d915:fab5
1832c19:dd:d9:dd:c25:c25:d915:fab6/1282c19:dd:d9:dd:c25:c25:d915:fab6
1842c19:dd:d9:dd:c25:c25:d915:fab7/1282c19:dd:d9:dd:c25:c25:d915:fab7
1852c19:dd:d9:dd:c25:c25:d915:fab8/1282c19:dd:d9:dd:c25:c25:d915:fab8
1862c19:dd:d9:dd:c25:c25:d915:fab9/1282c19:dd:d9:dd:c25:c25:d915:fab9
1872c19:dd:d9:dd:c25:c25:d915:faba/1282c19:dd:d9:dd:c25:c25:d915:faba
1882c19:dd:d9:dd:c25:c25:d915:fabb/1282c19:dd:d9:dd:c25:c25:d915:fabb
1892c19:dd:d9:dd:c25:c25:d915:fabc/1282c19:dd:d9:dd:c25:c25:d915:fabc
1902c19:dd:d9:dd:c25:c25:d915:fabd/1282c19:dd:d9:dd:c25:c25:d915:fabd
1912c19:dd:d9:dd:c25:c25:d915:fabe/1282c19:dd:d9:dd:c25:c25:d915:fabe
1922c19:dd:d9:dd:c25:c25:d915:fabf/1282c19:dd:d9:dd:c25:c25:d915:fabf
1932c19:dd:d9:dd:c25:c25:d915:fac0/1282c19:dd:d9:dd:c25:c25:d915:fac0
1942c19:dd:d9:dd:c25:c25:d915:fac1/1282c19:dd:d9:dd:c25:c25:d915:fac1
1952c19:dd:d9:dd:c25:c25:d915:fac2/1282c19:dd:d9:dd:c25:c25:d915:fac2
1962c19:dd:d9:dd:c25:c25:d915:fac3/1282c19:dd:d9:dd:c25:c25:d915:fac3
1972c19:dd:d9:dd:c25:c25:d915:fac4/1282c19:dd:d9:dd:c25:c25:d915:fac4
1982c19:dd:d9:dd:c25:c25:d915:fac5/1282c19:dd:d9:dd:c25:c25:d915:fac5
1992c19:dd:d9:dd:c25:c25:d915:fac6/1282c19:dd:d9:dd:c25:c25:d915:fac6
2002c19:dd:d9:dd:c25:c25:d915:fac7/1282c19:dd:d9:dd:c25:c25:d915:fac7
2012c19:dd:d9:dd:c25:c25:d915:fac8/1282c19:dd:d9:dd:c25:c25:d915:fac8
2022c19:dd:d9:dd:c25:c25:d915:fac9/1282c19:dd:d9:dd:c25:c25:d915:fac9
2032c19:dd:d9:dd:c25:c25:d915:faca/1282c19:dd:d9:dd:c25:c25:d915:faca
2042c19:dd:d9:dd:c25:c25:d915:facb/1282c19:dd:d9:dd:c25:c25:d915:facb
2052c19:dd:d9:dd:c25:c25:d915:facc/1282c19:dd:d9:dd:c25:c25:d915:facc
2062c19:dd:d9:dd:c25:c25:d915:facd/1282c19:dd:d9:dd:c25:c25:d915:facd
2072c19:dd:d9:dd:c25:c25:d915:face/1282c19:dd:d9:dd:c25:c25:d915:face
2082c19:dd:d9:dd:c25:c25:d915:facf/1282c19:dd:d9:dd:c25:c25:d915:facf
2092c19:dd:d9:dd:c25:c25:d915:fad0/1282c19:dd:d9:dd:c25:c25:d915:fad0
2102c19:dd:d9:dd:c25:c25:d915:fad1/1282c19:dd:d9:dd:c25:c25:d915:fad1
2112c19:dd:d9:dd:c25:c25:d915:fad2/1282c19:dd:d9:dd:c25:c25:d915:fad2
2122c19:dd:d9:dd:c25:c25:d915:fad3/1282c19:dd:d9:dd:c25:c25:d915:fad3
2132c19:dd:d9:dd:c25:c25:d915:fad4/1282c19:dd:d9:dd:c25:c25:d915:fad4
2142c19:dd:d9:dd:c25:c25:d915:fad5/1282c19:dd:d9:dd:c25:c25:d915:fad5
2152c19:dd:d9:dd:c25:c25:d915:fad6/1282c19:dd:d9:dd:c25:c25:d915:fad6
2162c19:dd:d9:dd:c25:c25:d915:fad7/1282c19:dd:d9:dd:c25:c25:d915:fad7
2172c19:dd:d9:dd:c25:c25:d915:fad8/1282c19:dd:d9:dd:c25:c25:d915:fad8
2182c19:dd:d9:dd:c25:c25:d915:fad9/1282c19:dd:d9:dd:c25:c25:d915:fad9
2192c19:dd:d9:dd:c25:c25:d915:fada/1282c19:dd:d9:dd:c25:c25:d915:fada
2202c19:dd:d9:dd:c25:c25:d915:fadb/1282c19:dd:d9:dd:c25:c25:d915:fadb
2212c19:dd:d9:dd:c25:c25:d915:fadc/1282c19:dd:d9:dd:c25:c25:d915:fadc
2222c19:dd:d9:dd:c25:c25:d915:fadd/1282c19:dd:d9:dd:c25:c25:d915:fadd
2232c19:dd:d9:dd:c25:c25:d915:fade/1282c19:dd:d9:dd:c25:c25:d915:fade
2242c19:dd:d9:dd:c25:c25:d915:fadf/1282c19:dd:d9:dd:c25:c25:d915:fadf
2252c19:dd:d9:dd:c25:c25:d915:fae0/1282c19:dd:d9:dd:c25:c25:d915:fae0
2262c19:dd:d9:dd:c25:c25:d915:fae1/1282c19:dd:d9:dd:c25:c25:d915:fae1
2272c19:dd:d9:dd:c25:c25:d915:fae2/1282c19:dd:d9:dd:c25:c25:d915:fae2
2282c19:dd:d9:dd:c25:c25:d915:fae3/1282c19:dd:d9:dd:c25:c25:d915:fae3
2292c19:dd:d9:dd:c25:c25:d915:fae4/1282c19:dd:d9:dd:c25:c25:d915:fae4
2302c19:dd:d9:dd:c25:c25:d915:fae5/1282c19:dd:d9:dd:c25:c25:d915:fae5
2312c19:dd:d9:dd:c25:c25:d915:fae6/1282c19:dd:d9:dd:c25:c25:d915:fae6
2322c19:dd:d9:dd:c25:c25:d915:fae7/1282c19:dd:d9:dd:c25:c25:d915:fae7
2332c19:dd:d9:dd:c25:c25:d915:fae8/1282c19:dd:d9:dd:c25:c25:d915:fae8
2342c19:dd:d9:dd:c25:c25:d915:fae9/1282c19:dd:d9:dd:c25:c25:d915:fae9
2352c19:dd:d9:dd:c25:c25:d915:faea/1282c19:dd:d9:dd:c25:c25:d915:faea
2362c19:dd:d9:dd:c25:c25:d915:faeb/1282c19:dd:d9:dd:c25:c25:d915:faeb
2372c19:dd:d9:dd:c25:c25:d915:faec/1282c19:dd:d9:dd:c25:c25:d915:faec
2382c19:dd:d9:dd:c25:c25:d915:faed/1282c19:dd:d9:dd:c25:c25:d915:faed
2392c19:dd:d9:dd:c25:c25:d915:faee/1282c19:dd:d9:dd:c25:c25:d915:faee
2402c19:dd:d9:dd:c25:c25:d915:faef/1282c19:dd:d9:dd:c25:c25:d915:faef
2412c19:dd:d9:dd:c25:c25:d915:faf0/1282c19:dd:d9:dd:c25:c25:d915:faf0
2422c19:dd:d9:dd:c25:c25:d915:faf1/1282c19:dd:d9:dd:c25:c25:d915:faf1
2432c19:dd:d9:dd:c25:c25:d915:faf2/1282c19:dd:d9:dd:c25:c25:d915:faf2
2442c19:dd:d9:dd:c25:c25:d915:faf3/1282c19:dd:d9:dd:c25:c25:d915:faf3
2452c19:dd:d9:dd:c25:c25:d915:faf4/1282c19:dd:d9:dd:c25:c25:d915:faf4
2462c19:dd:d9:dd:c25:c25:d915:faf5/1282c19:dd:d9:dd:c25:c25:d915:faf5
2472c19:dd:d9:dd:c25:c25:d915:faf6/1282c19:dd:d9:dd:c25:c25:d915:faf6
2482c19:dd:d9:dd:c25:c25:d915:faf7/1282c19:dd:d9:dd:c25:c25:d915:faf7
2492c19:dd:d9:dd:c25:c25:d915:faf8/1282c19:dd:d9:dd:c25:c25:d915:faf8
2502c19:dd:d9:dd:c25:c25:d915:faf9/1282c19:dd:d9:dd:c25:c25:d915:faf9
2512c19:dd:d9:dd:c25:c25:d915:fafa/1282c19:dd:d9:dd:c25:c25:d915:fafa
2522c19:dd:d9:dd:c25:c25:d915:fafb/1282c19:dd:d9:dd:c25:c25:d915:fafb
2532c19:dd:d9:dd:c25:c25:d915:fafc/1282c19:dd:d9:dd:c25:c25:d915:fafc
2542c19:dd:d9:dd:c25:c25:d915:fafd/1282c19:dd:d9:dd:c25:c25:d915:fafd
2552c19:dd:d9:dd:c25:c25:d915:fafe/1282c19:dd:d9:dd:c25:c25:d915:fafe
2562c19:dd:d9:dd:c25:c25:d915:faff/1282c19:dd:d9:dd:c25:c25:d915:faff

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.