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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:be00/120
First address
2c19:dd:c25:c25d:dd:dd:dd:be00
Last address
2c19:dd:c25:c25d:dd:dd:dd:beff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:be00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.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:be00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:be00/1282c19:dd:c25:c25d:dd:dd:dd:be00
22c19:dd:c25:c25d:dd:dd:dd:be01/1282c19:dd:c25:c25d:dd:dd:dd:be01
32c19:dd:c25:c25d:dd:dd:dd:be02/1282c19:dd:c25:c25d:dd:dd:dd:be02
42c19:dd:c25:c25d:dd:dd:dd:be03/1282c19:dd:c25:c25d:dd:dd:dd:be03
52c19:dd:c25:c25d:dd:dd:dd:be04/1282c19:dd:c25:c25d:dd:dd:dd:be04
62c19:dd:c25:c25d:dd:dd:dd:be05/1282c19:dd:c25:c25d:dd:dd:dd:be05
72c19:dd:c25:c25d:dd:dd:dd:be06/1282c19:dd:c25:c25d:dd:dd:dd:be06
82c19:dd:c25:c25d:dd:dd:dd:be07/1282c19:dd:c25:c25d:dd:dd:dd:be07
92c19:dd:c25:c25d:dd:dd:dd:be08/1282c19:dd:c25:c25d:dd:dd:dd:be08
102c19:dd:c25:c25d:dd:dd:dd:be09/1282c19:dd:c25:c25d:dd:dd:dd:be09
112c19:dd:c25:c25d:dd:dd:dd:be0a/1282c19:dd:c25:c25d:dd:dd:dd:be0a
122c19:dd:c25:c25d:dd:dd:dd:be0b/1282c19:dd:c25:c25d:dd:dd:dd:be0b
132c19:dd:c25:c25d:dd:dd:dd:be0c/1282c19:dd:c25:c25d:dd:dd:dd:be0c
142c19:dd:c25:c25d:dd:dd:dd:be0d/1282c19:dd:c25:c25d:dd:dd:dd:be0d
152c19:dd:c25:c25d:dd:dd:dd:be0e/1282c19:dd:c25:c25d:dd:dd:dd:be0e
162c19:dd:c25:c25d:dd:dd:dd:be0f/1282c19:dd:c25:c25d:dd:dd:dd:be0f
172c19:dd:c25:c25d:dd:dd:dd:be10/1282c19:dd:c25:c25d:dd:dd:dd:be10
182c19:dd:c25:c25d:dd:dd:dd:be11/1282c19:dd:c25:c25d:dd:dd:dd:be11
192c19:dd:c25:c25d:dd:dd:dd:be12/1282c19:dd:c25:c25d:dd:dd:dd:be12
202c19:dd:c25:c25d:dd:dd:dd:be13/1282c19:dd:c25:c25d:dd:dd:dd:be13
212c19:dd:c25:c25d:dd:dd:dd:be14/1282c19:dd:c25:c25d:dd:dd:dd:be14
222c19:dd:c25:c25d:dd:dd:dd:be15/1282c19:dd:c25:c25d:dd:dd:dd:be15
232c19:dd:c25:c25d:dd:dd:dd:be16/1282c19:dd:c25:c25d:dd:dd:dd:be16
242c19:dd:c25:c25d:dd:dd:dd:be17/1282c19:dd:c25:c25d:dd:dd:dd:be17
252c19:dd:c25:c25d:dd:dd:dd:be18/1282c19:dd:c25:c25d:dd:dd:dd:be18
262c19:dd:c25:c25d:dd:dd:dd:be19/1282c19:dd:c25:c25d:dd:dd:dd:be19
272c19:dd:c25:c25d:dd:dd:dd:be1a/1282c19:dd:c25:c25d:dd:dd:dd:be1a
282c19:dd:c25:c25d:dd:dd:dd:be1b/1282c19:dd:c25:c25d:dd:dd:dd:be1b
292c19:dd:c25:c25d:dd:dd:dd:be1c/1282c19:dd:c25:c25d:dd:dd:dd:be1c
302c19:dd:c25:c25d:dd:dd:dd:be1d/1282c19:dd:c25:c25d:dd:dd:dd:be1d
312c19:dd:c25:c25d:dd:dd:dd:be1e/1282c19:dd:c25:c25d:dd:dd:dd:be1e
322c19:dd:c25:c25d:dd:dd:dd:be1f/1282c19:dd:c25:c25d:dd:dd:dd:be1f
332c19:dd:c25:c25d:dd:dd:dd:be20/1282c19:dd:c25:c25d:dd:dd:dd:be20
342c19:dd:c25:c25d:dd:dd:dd:be21/1282c19:dd:c25:c25d:dd:dd:dd:be21
352c19:dd:c25:c25d:dd:dd:dd:be22/1282c19:dd:c25:c25d:dd:dd:dd:be22
362c19:dd:c25:c25d:dd:dd:dd:be23/1282c19:dd:c25:c25d:dd:dd:dd:be23
372c19:dd:c25:c25d:dd:dd:dd:be24/1282c19:dd:c25:c25d:dd:dd:dd:be24
382c19:dd:c25:c25d:dd:dd:dd:be25/1282c19:dd:c25:c25d:dd:dd:dd:be25
392c19:dd:c25:c25d:dd:dd:dd:be26/1282c19:dd:c25:c25d:dd:dd:dd:be26
402c19:dd:c25:c25d:dd:dd:dd:be27/1282c19:dd:c25:c25d:dd:dd:dd:be27
412c19:dd:c25:c25d:dd:dd:dd:be28/1282c19:dd:c25:c25d:dd:dd:dd:be28
422c19:dd:c25:c25d:dd:dd:dd:be29/1282c19:dd:c25:c25d:dd:dd:dd:be29
432c19:dd:c25:c25d:dd:dd:dd:be2a/1282c19:dd:c25:c25d:dd:dd:dd:be2a
442c19:dd:c25:c25d:dd:dd:dd:be2b/1282c19:dd:c25:c25d:dd:dd:dd:be2b
452c19:dd:c25:c25d:dd:dd:dd:be2c/1282c19:dd:c25:c25d:dd:dd:dd:be2c
462c19:dd:c25:c25d:dd:dd:dd:be2d/1282c19:dd:c25:c25d:dd:dd:dd:be2d
472c19:dd:c25:c25d:dd:dd:dd:be2e/1282c19:dd:c25:c25d:dd:dd:dd:be2e
482c19:dd:c25:c25d:dd:dd:dd:be2f/1282c19:dd:c25:c25d:dd:dd:dd:be2f
492c19:dd:c25:c25d:dd:dd:dd:be30/1282c19:dd:c25:c25d:dd:dd:dd:be30
502c19:dd:c25:c25d:dd:dd:dd:be31/1282c19:dd:c25:c25d:dd:dd:dd:be31
512c19:dd:c25:c25d:dd:dd:dd:be32/1282c19:dd:c25:c25d:dd:dd:dd:be32
522c19:dd:c25:c25d:dd:dd:dd:be33/1282c19:dd:c25:c25d:dd:dd:dd:be33
532c19:dd:c25:c25d:dd:dd:dd:be34/1282c19:dd:c25:c25d:dd:dd:dd:be34
542c19:dd:c25:c25d:dd:dd:dd:be35/1282c19:dd:c25:c25d:dd:dd:dd:be35
552c19:dd:c25:c25d:dd:dd:dd:be36/1282c19:dd:c25:c25d:dd:dd:dd:be36
562c19:dd:c25:c25d:dd:dd:dd:be37/1282c19:dd:c25:c25d:dd:dd:dd:be37
572c19:dd:c25:c25d:dd:dd:dd:be38/1282c19:dd:c25:c25d:dd:dd:dd:be38
582c19:dd:c25:c25d:dd:dd:dd:be39/1282c19:dd:c25:c25d:dd:dd:dd:be39
592c19:dd:c25:c25d:dd:dd:dd:be3a/1282c19:dd:c25:c25d:dd:dd:dd:be3a
602c19:dd:c25:c25d:dd:dd:dd:be3b/1282c19:dd:c25:c25d:dd:dd:dd:be3b
612c19:dd:c25:c25d:dd:dd:dd:be3c/1282c19:dd:c25:c25d:dd:dd:dd:be3c
622c19:dd:c25:c25d:dd:dd:dd:be3d/1282c19:dd:c25:c25d:dd:dd:dd:be3d
632c19:dd:c25:c25d:dd:dd:dd:be3e/1282c19:dd:c25:c25d:dd:dd:dd:be3e
642c19:dd:c25:c25d:dd:dd:dd:be3f/1282c19:dd:c25:c25d:dd:dd:dd:be3f
652c19:dd:c25:c25d:dd:dd:dd:be40/1282c19:dd:c25:c25d:dd:dd:dd:be40
662c19:dd:c25:c25d:dd:dd:dd:be41/1282c19:dd:c25:c25d:dd:dd:dd:be41
672c19:dd:c25:c25d:dd:dd:dd:be42/1282c19:dd:c25:c25d:dd:dd:dd:be42
682c19:dd:c25:c25d:dd:dd:dd:be43/1282c19:dd:c25:c25d:dd:dd:dd:be43
692c19:dd:c25:c25d:dd:dd:dd:be44/1282c19:dd:c25:c25d:dd:dd:dd:be44
702c19:dd:c25:c25d:dd:dd:dd:be45/1282c19:dd:c25:c25d:dd:dd:dd:be45
712c19:dd:c25:c25d:dd:dd:dd:be46/1282c19:dd:c25:c25d:dd:dd:dd:be46
722c19:dd:c25:c25d:dd:dd:dd:be47/1282c19:dd:c25:c25d:dd:dd:dd:be47
732c19:dd:c25:c25d:dd:dd:dd:be48/1282c19:dd:c25:c25d:dd:dd:dd:be48
742c19:dd:c25:c25d:dd:dd:dd:be49/1282c19:dd:c25:c25d:dd:dd:dd:be49
752c19:dd:c25:c25d:dd:dd:dd:be4a/1282c19:dd:c25:c25d:dd:dd:dd:be4a
762c19:dd:c25:c25d:dd:dd:dd:be4b/1282c19:dd:c25:c25d:dd:dd:dd:be4b
772c19:dd:c25:c25d:dd:dd:dd:be4c/1282c19:dd:c25:c25d:dd:dd:dd:be4c
782c19:dd:c25:c25d:dd:dd:dd:be4d/1282c19:dd:c25:c25d:dd:dd:dd:be4d
792c19:dd:c25:c25d:dd:dd:dd:be4e/1282c19:dd:c25:c25d:dd:dd:dd:be4e
802c19:dd:c25:c25d:dd:dd:dd:be4f/1282c19:dd:c25:c25d:dd:dd:dd:be4f
812c19:dd:c25:c25d:dd:dd:dd:be50/1282c19:dd:c25:c25d:dd:dd:dd:be50
822c19:dd:c25:c25d:dd:dd:dd:be51/1282c19:dd:c25:c25d:dd:dd:dd:be51
832c19:dd:c25:c25d:dd:dd:dd:be52/1282c19:dd:c25:c25d:dd:dd:dd:be52
842c19:dd:c25:c25d:dd:dd:dd:be53/1282c19:dd:c25:c25d:dd:dd:dd:be53
852c19:dd:c25:c25d:dd:dd:dd:be54/1282c19:dd:c25:c25d:dd:dd:dd:be54
862c19:dd:c25:c25d:dd:dd:dd:be55/1282c19:dd:c25:c25d:dd:dd:dd:be55
872c19:dd:c25:c25d:dd:dd:dd:be56/1282c19:dd:c25:c25d:dd:dd:dd:be56
882c19:dd:c25:c25d:dd:dd:dd:be57/1282c19:dd:c25:c25d:dd:dd:dd:be57
892c19:dd:c25:c25d:dd:dd:dd:be58/1282c19:dd:c25:c25d:dd:dd:dd:be58
902c19:dd:c25:c25d:dd:dd:dd:be59/1282c19:dd:c25:c25d:dd:dd:dd:be59
912c19:dd:c25:c25d:dd:dd:dd:be5a/1282c19:dd:c25:c25d:dd:dd:dd:be5a
922c19:dd:c25:c25d:dd:dd:dd:be5b/1282c19:dd:c25:c25d:dd:dd:dd:be5b
932c19:dd:c25:c25d:dd:dd:dd:be5c/1282c19:dd:c25:c25d:dd:dd:dd:be5c
942c19:dd:c25:c25d:dd:dd:dd:be5d/1282c19:dd:c25:c25d:dd:dd:dd:be5d
952c19:dd:c25:c25d:dd:dd:dd:be5e/1282c19:dd:c25:c25d:dd:dd:dd:be5e
962c19:dd:c25:c25d:dd:dd:dd:be5f/1282c19:dd:c25:c25d:dd:dd:dd:be5f
972c19:dd:c25:c25d:dd:dd:dd:be60/1282c19:dd:c25:c25d:dd:dd:dd:be60
982c19:dd:c25:c25d:dd:dd:dd:be61/1282c19:dd:c25:c25d:dd:dd:dd:be61
992c19:dd:c25:c25d:dd:dd:dd:be62/1282c19:dd:c25:c25d:dd:dd:dd:be62
1002c19:dd:c25:c25d:dd:dd:dd:be63/1282c19:dd:c25:c25d:dd:dd:dd:be63
1012c19:dd:c25:c25d:dd:dd:dd:be64/1282c19:dd:c25:c25d:dd:dd:dd:be64
1022c19:dd:c25:c25d:dd:dd:dd:be65/1282c19:dd:c25:c25d:dd:dd:dd:be65
1032c19:dd:c25:c25d:dd:dd:dd:be66/1282c19:dd:c25:c25d:dd:dd:dd:be66
1042c19:dd:c25:c25d:dd:dd:dd:be67/1282c19:dd:c25:c25d:dd:dd:dd:be67
1052c19:dd:c25:c25d:dd:dd:dd:be68/1282c19:dd:c25:c25d:dd:dd:dd:be68
1062c19:dd:c25:c25d:dd:dd:dd:be69/1282c19:dd:c25:c25d:dd:dd:dd:be69
1072c19:dd:c25:c25d:dd:dd:dd:be6a/1282c19:dd:c25:c25d:dd:dd:dd:be6a
1082c19:dd:c25:c25d:dd:dd:dd:be6b/1282c19:dd:c25:c25d:dd:dd:dd:be6b
1092c19:dd:c25:c25d:dd:dd:dd:be6c/1282c19:dd:c25:c25d:dd:dd:dd:be6c
1102c19:dd:c25:c25d:dd:dd:dd:be6d/1282c19:dd:c25:c25d:dd:dd:dd:be6d
1112c19:dd:c25:c25d:dd:dd:dd:be6e/1282c19:dd:c25:c25d:dd:dd:dd:be6e
1122c19:dd:c25:c25d:dd:dd:dd:be6f/1282c19:dd:c25:c25d:dd:dd:dd:be6f
1132c19:dd:c25:c25d:dd:dd:dd:be70/1282c19:dd:c25:c25d:dd:dd:dd:be70
1142c19:dd:c25:c25d:dd:dd:dd:be71/1282c19:dd:c25:c25d:dd:dd:dd:be71
1152c19:dd:c25:c25d:dd:dd:dd:be72/1282c19:dd:c25:c25d:dd:dd:dd:be72
1162c19:dd:c25:c25d:dd:dd:dd:be73/1282c19:dd:c25:c25d:dd:dd:dd:be73
1172c19:dd:c25:c25d:dd:dd:dd:be74/1282c19:dd:c25:c25d:dd:dd:dd:be74
1182c19:dd:c25:c25d:dd:dd:dd:be75/1282c19:dd:c25:c25d:dd:dd:dd:be75
1192c19:dd:c25:c25d:dd:dd:dd:be76/1282c19:dd:c25:c25d:dd:dd:dd:be76
1202c19:dd:c25:c25d:dd:dd:dd:be77/1282c19:dd:c25:c25d:dd:dd:dd:be77
1212c19:dd:c25:c25d:dd:dd:dd:be78/1282c19:dd:c25:c25d:dd:dd:dd:be78
1222c19:dd:c25:c25d:dd:dd:dd:be79/1282c19:dd:c25:c25d:dd:dd:dd:be79
1232c19:dd:c25:c25d:dd:dd:dd:be7a/1282c19:dd:c25:c25d:dd:dd:dd:be7a
1242c19:dd:c25:c25d:dd:dd:dd:be7b/1282c19:dd:c25:c25d:dd:dd:dd:be7b
1252c19:dd:c25:c25d:dd:dd:dd:be7c/1282c19:dd:c25:c25d:dd:dd:dd:be7c
1262c19:dd:c25:c25d:dd:dd:dd:be7d/1282c19:dd:c25:c25d:dd:dd:dd:be7d
1272c19:dd:c25:c25d:dd:dd:dd:be7e/1282c19:dd:c25:c25d:dd:dd:dd:be7e
1282c19:dd:c25:c25d:dd:dd:dd:be7f/1282c19:dd:c25:c25d:dd:dd:dd:be7f
1292c19:dd:c25:c25d:dd:dd:dd:be80/1282c19:dd:c25:c25d:dd:dd:dd:be80
1302c19:dd:c25:c25d:dd:dd:dd:be81/1282c19:dd:c25:c25d:dd:dd:dd:be81
1312c19:dd:c25:c25d:dd:dd:dd:be82/1282c19:dd:c25:c25d:dd:dd:dd:be82
1322c19:dd:c25:c25d:dd:dd:dd:be83/1282c19:dd:c25:c25d:dd:dd:dd:be83
1332c19:dd:c25:c25d:dd:dd:dd:be84/1282c19:dd:c25:c25d:dd:dd:dd:be84
1342c19:dd:c25:c25d:dd:dd:dd:be85/1282c19:dd:c25:c25d:dd:dd:dd:be85
1352c19:dd:c25:c25d:dd:dd:dd:be86/1282c19:dd:c25:c25d:dd:dd:dd:be86
1362c19:dd:c25:c25d:dd:dd:dd:be87/1282c19:dd:c25:c25d:dd:dd:dd:be87
1372c19:dd:c25:c25d:dd:dd:dd:be88/1282c19:dd:c25:c25d:dd:dd:dd:be88
1382c19:dd:c25:c25d:dd:dd:dd:be89/1282c19:dd:c25:c25d:dd:dd:dd:be89
1392c19:dd:c25:c25d:dd:dd:dd:be8a/1282c19:dd:c25:c25d:dd:dd:dd:be8a
1402c19:dd:c25:c25d:dd:dd:dd:be8b/1282c19:dd:c25:c25d:dd:dd:dd:be8b
1412c19:dd:c25:c25d:dd:dd:dd:be8c/1282c19:dd:c25:c25d:dd:dd:dd:be8c
1422c19:dd:c25:c25d:dd:dd:dd:be8d/1282c19:dd:c25:c25d:dd:dd:dd:be8d
1432c19:dd:c25:c25d:dd:dd:dd:be8e/1282c19:dd:c25:c25d:dd:dd:dd:be8e
1442c19:dd:c25:c25d:dd:dd:dd:be8f/1282c19:dd:c25:c25d:dd:dd:dd:be8f
1452c19:dd:c25:c25d:dd:dd:dd:be90/1282c19:dd:c25:c25d:dd:dd:dd:be90
1462c19:dd:c25:c25d:dd:dd:dd:be91/1282c19:dd:c25:c25d:dd:dd:dd:be91
1472c19:dd:c25:c25d:dd:dd:dd:be92/1282c19:dd:c25:c25d:dd:dd:dd:be92
1482c19:dd:c25:c25d:dd:dd:dd:be93/1282c19:dd:c25:c25d:dd:dd:dd:be93
1492c19:dd:c25:c25d:dd:dd:dd:be94/1282c19:dd:c25:c25d:dd:dd:dd:be94
1502c19:dd:c25:c25d:dd:dd:dd:be95/1282c19:dd:c25:c25d:dd:dd:dd:be95
1512c19:dd:c25:c25d:dd:dd:dd:be96/1282c19:dd:c25:c25d:dd:dd:dd:be96
1522c19:dd:c25:c25d:dd:dd:dd:be97/1282c19:dd:c25:c25d:dd:dd:dd:be97
1532c19:dd:c25:c25d:dd:dd:dd:be98/1282c19:dd:c25:c25d:dd:dd:dd:be98
1542c19:dd:c25:c25d:dd:dd:dd:be99/1282c19:dd:c25:c25d:dd:dd:dd:be99
1552c19:dd:c25:c25d:dd:dd:dd:be9a/1282c19:dd:c25:c25d:dd:dd:dd:be9a
1562c19:dd:c25:c25d:dd:dd:dd:be9b/1282c19:dd:c25:c25d:dd:dd:dd:be9b
1572c19:dd:c25:c25d:dd:dd:dd:be9c/1282c19:dd:c25:c25d:dd:dd:dd:be9c
1582c19:dd:c25:c25d:dd:dd:dd:be9d/1282c19:dd:c25:c25d:dd:dd:dd:be9d
1592c19:dd:c25:c25d:dd:dd:dd:be9e/1282c19:dd:c25:c25d:dd:dd:dd:be9e
1602c19:dd:c25:c25d:dd:dd:dd:be9f/1282c19:dd:c25:c25d:dd:dd:dd:be9f
1612c19:dd:c25:c25d:dd:dd:dd:bea0/1282c19:dd:c25:c25d:dd:dd:dd:bea0
1622c19:dd:c25:c25d:dd:dd:dd:bea1/1282c19:dd:c25:c25d:dd:dd:dd:bea1
1632c19:dd:c25:c25d:dd:dd:dd:bea2/1282c19:dd:c25:c25d:dd:dd:dd:bea2
1642c19:dd:c25:c25d:dd:dd:dd:bea3/1282c19:dd:c25:c25d:dd:dd:dd:bea3
1652c19:dd:c25:c25d:dd:dd:dd:bea4/1282c19:dd:c25:c25d:dd:dd:dd:bea4
1662c19:dd:c25:c25d:dd:dd:dd:bea5/1282c19:dd:c25:c25d:dd:dd:dd:bea5
1672c19:dd:c25:c25d:dd:dd:dd:bea6/1282c19:dd:c25:c25d:dd:dd:dd:bea6
1682c19:dd:c25:c25d:dd:dd:dd:bea7/1282c19:dd:c25:c25d:dd:dd:dd:bea7
1692c19:dd:c25:c25d:dd:dd:dd:bea8/1282c19:dd:c25:c25d:dd:dd:dd:bea8
1702c19:dd:c25:c25d:dd:dd:dd:bea9/1282c19:dd:c25:c25d:dd:dd:dd:bea9
1712c19:dd:c25:c25d:dd:dd:dd:beaa/1282c19:dd:c25:c25d:dd:dd:dd:beaa
1722c19:dd:c25:c25d:dd:dd:dd:beab/1282c19:dd:c25:c25d:dd:dd:dd:beab
1732c19:dd:c25:c25d:dd:dd:dd:beac/1282c19:dd:c25:c25d:dd:dd:dd:beac
1742c19:dd:c25:c25d:dd:dd:dd:bead/1282c19:dd:c25:c25d:dd:dd:dd:bead
1752c19:dd:c25:c25d:dd:dd:dd:beae/1282c19:dd:c25:c25d:dd:dd:dd:beae
1762c19:dd:c25:c25d:dd:dd:dd:beaf/1282c19:dd:c25:c25d:dd:dd:dd:beaf
1772c19:dd:c25:c25d:dd:dd:dd:beb0/1282c19:dd:c25:c25d:dd:dd:dd:beb0
1782c19:dd:c25:c25d:dd:dd:dd:beb1/1282c19:dd:c25:c25d:dd:dd:dd:beb1
1792c19:dd:c25:c25d:dd:dd:dd:beb2/1282c19:dd:c25:c25d:dd:dd:dd:beb2
1802c19:dd:c25:c25d:dd:dd:dd:beb3/1282c19:dd:c25:c25d:dd:dd:dd:beb3
1812c19:dd:c25:c25d:dd:dd:dd:beb4/1282c19:dd:c25:c25d:dd:dd:dd:beb4
1822c19:dd:c25:c25d:dd:dd:dd:beb5/1282c19:dd:c25:c25d:dd:dd:dd:beb5
1832c19:dd:c25:c25d:dd:dd:dd:beb6/1282c19:dd:c25:c25d:dd:dd:dd:beb6
1842c19:dd:c25:c25d:dd:dd:dd:beb7/1282c19:dd:c25:c25d:dd:dd:dd:beb7
1852c19:dd:c25:c25d:dd:dd:dd:beb8/1282c19:dd:c25:c25d:dd:dd:dd:beb8
1862c19:dd:c25:c25d:dd:dd:dd:beb9/1282c19:dd:c25:c25d:dd:dd:dd:beb9
1872c19:dd:c25:c25d:dd:dd:dd:beba/1282c19:dd:c25:c25d:dd:dd:dd:beba
1882c19:dd:c25:c25d:dd:dd:dd:bebb/1282c19:dd:c25:c25d:dd:dd:dd:bebb
1892c19:dd:c25:c25d:dd:dd:dd:bebc/1282c19:dd:c25:c25d:dd:dd:dd:bebc
1902c19:dd:c25:c25d:dd:dd:dd:bebd/1282c19:dd:c25:c25d:dd:dd:dd:bebd
1912c19:dd:c25:c25d:dd:dd:dd:bebe/1282c19:dd:c25:c25d:dd:dd:dd:bebe
1922c19:dd:c25:c25d:dd:dd:dd:bebf/1282c19:dd:c25:c25d:dd:dd:dd:bebf
1932c19:dd:c25:c25d:dd:dd:dd:bec0/1282c19:dd:c25:c25d:dd:dd:dd:bec0
1942c19:dd:c25:c25d:dd:dd:dd:bec1/1282c19:dd:c25:c25d:dd:dd:dd:bec1
1952c19:dd:c25:c25d:dd:dd:dd:bec2/1282c19:dd:c25:c25d:dd:dd:dd:bec2
1962c19:dd:c25:c25d:dd:dd:dd:bec3/1282c19:dd:c25:c25d:dd:dd:dd:bec3
1972c19:dd:c25:c25d:dd:dd:dd:bec4/1282c19:dd:c25:c25d:dd:dd:dd:bec4
1982c19:dd:c25:c25d:dd:dd:dd:bec5/1282c19:dd:c25:c25d:dd:dd:dd:bec5
1992c19:dd:c25:c25d:dd:dd:dd:bec6/1282c19:dd:c25:c25d:dd:dd:dd:bec6
2002c19:dd:c25:c25d:dd:dd:dd:bec7/1282c19:dd:c25:c25d:dd:dd:dd:bec7
2012c19:dd:c25:c25d:dd:dd:dd:bec8/1282c19:dd:c25:c25d:dd:dd:dd:bec8
2022c19:dd:c25:c25d:dd:dd:dd:bec9/1282c19:dd:c25:c25d:dd:dd:dd:bec9
2032c19:dd:c25:c25d:dd:dd:dd:beca/1282c19:dd:c25:c25d:dd:dd:dd:beca
2042c19:dd:c25:c25d:dd:dd:dd:becb/1282c19:dd:c25:c25d:dd:dd:dd:becb
2052c19:dd:c25:c25d:dd:dd:dd:becc/1282c19:dd:c25:c25d:dd:dd:dd:becc
2062c19:dd:c25:c25d:dd:dd:dd:becd/1282c19:dd:c25:c25d:dd:dd:dd:becd
2072c19:dd:c25:c25d:dd:dd:dd:bece/1282c19:dd:c25:c25d:dd:dd:dd:bece
2082c19:dd:c25:c25d:dd:dd:dd:becf/1282c19:dd:c25:c25d:dd:dd:dd:becf
2092c19:dd:c25:c25d:dd:dd:dd:bed0/1282c19:dd:c25:c25d:dd:dd:dd:bed0
2102c19:dd:c25:c25d:dd:dd:dd:bed1/1282c19:dd:c25:c25d:dd:dd:dd:bed1
2112c19:dd:c25:c25d:dd:dd:dd:bed2/1282c19:dd:c25:c25d:dd:dd:dd:bed2
2122c19:dd:c25:c25d:dd:dd:dd:bed3/1282c19:dd:c25:c25d:dd:dd:dd:bed3
2132c19:dd:c25:c25d:dd:dd:dd:bed4/1282c19:dd:c25:c25d:dd:dd:dd:bed4
2142c19:dd:c25:c25d:dd:dd:dd:bed5/1282c19:dd:c25:c25d:dd:dd:dd:bed5
2152c19:dd:c25:c25d:dd:dd:dd:bed6/1282c19:dd:c25:c25d:dd:dd:dd:bed6
2162c19:dd:c25:c25d:dd:dd:dd:bed7/1282c19:dd:c25:c25d:dd:dd:dd:bed7
2172c19:dd:c25:c25d:dd:dd:dd:bed8/1282c19:dd:c25:c25d:dd:dd:dd:bed8
2182c19:dd:c25:c25d:dd:dd:dd:bed9/1282c19:dd:c25:c25d:dd:dd:dd:bed9
2192c19:dd:c25:c25d:dd:dd:dd:beda/1282c19:dd:c25:c25d:dd:dd:dd:beda
2202c19:dd:c25:c25d:dd:dd:dd:bedb/1282c19:dd:c25:c25d:dd:dd:dd:bedb
2212c19:dd:c25:c25d:dd:dd:dd:bedc/1282c19:dd:c25:c25d:dd:dd:dd:bedc
2222c19:dd:c25:c25d:dd:dd:dd:bedd/1282c19:dd:c25:c25d:dd:dd:dd:bedd
2232c19:dd:c25:c25d:dd:dd:dd:bede/1282c19:dd:c25:c25d:dd:dd:dd:bede
2242c19:dd:c25:c25d:dd:dd:dd:bedf/1282c19:dd:c25:c25d:dd:dd:dd:bedf
2252c19:dd:c25:c25d:dd:dd:dd:bee0/1282c19:dd:c25:c25d:dd:dd:dd:bee0
2262c19:dd:c25:c25d:dd:dd:dd:bee1/1282c19:dd:c25:c25d:dd:dd:dd:bee1
2272c19:dd:c25:c25d:dd:dd:dd:bee2/1282c19:dd:c25:c25d:dd:dd:dd:bee2
2282c19:dd:c25:c25d:dd:dd:dd:bee3/1282c19:dd:c25:c25d:dd:dd:dd:bee3
2292c19:dd:c25:c25d:dd:dd:dd:bee4/1282c19:dd:c25:c25d:dd:dd:dd:bee4
2302c19:dd:c25:c25d:dd:dd:dd:bee5/1282c19:dd:c25:c25d:dd:dd:dd:bee5
2312c19:dd:c25:c25d:dd:dd:dd:bee6/1282c19:dd:c25:c25d:dd:dd:dd:bee6
2322c19:dd:c25:c25d:dd:dd:dd:bee7/1282c19:dd:c25:c25d:dd:dd:dd:bee7
2332c19:dd:c25:c25d:dd:dd:dd:bee8/1282c19:dd:c25:c25d:dd:dd:dd:bee8
2342c19:dd:c25:c25d:dd:dd:dd:bee9/1282c19:dd:c25:c25d:dd:dd:dd:bee9
2352c19:dd:c25:c25d:dd:dd:dd:beea/1282c19:dd:c25:c25d:dd:dd:dd:beea
2362c19:dd:c25:c25d:dd:dd:dd:beeb/1282c19:dd:c25:c25d:dd:dd:dd:beeb
2372c19:dd:c25:c25d:dd:dd:dd:beec/1282c19:dd:c25:c25d:dd:dd:dd:beec
2382c19:dd:c25:c25d:dd:dd:dd:beed/1282c19:dd:c25:c25d:dd:dd:dd:beed
2392c19:dd:c25:c25d:dd:dd:dd:beee/1282c19:dd:c25:c25d:dd:dd:dd:beee
2402c19:dd:c25:c25d:dd:dd:dd:beef/1282c19:dd:c25:c25d:dd:dd:dd:beef
2412c19:dd:c25:c25d:dd:dd:dd:bef0/1282c19:dd:c25:c25d:dd:dd:dd:bef0
2422c19:dd:c25:c25d:dd:dd:dd:bef1/1282c19:dd:c25:c25d:dd:dd:dd:bef1
2432c19:dd:c25:c25d:dd:dd:dd:bef2/1282c19:dd:c25:c25d:dd:dd:dd:bef2
2442c19:dd:c25:c25d:dd:dd:dd:bef3/1282c19:dd:c25:c25d:dd:dd:dd:bef3
2452c19:dd:c25:c25d:dd:dd:dd:bef4/1282c19:dd:c25:c25d:dd:dd:dd:bef4
2462c19:dd:c25:c25d:dd:dd:dd:bef5/1282c19:dd:c25:c25d:dd:dd:dd:bef5
2472c19:dd:c25:c25d:dd:dd:dd:bef6/1282c19:dd:c25:c25d:dd:dd:dd:bef6
2482c19:dd:c25:c25d:dd:dd:dd:bef7/1282c19:dd:c25:c25d:dd:dd:dd:bef7
2492c19:dd:c25:c25d:dd:dd:dd:bef8/1282c19:dd:c25:c25d:dd:dd:dd:bef8
2502c19:dd:c25:c25d:dd:dd:dd:bef9/1282c19:dd:c25:c25d:dd:dd:dd:bef9
2512c19:dd:c25:c25d:dd:dd:dd:befa/1282c19:dd:c25:c25d:dd:dd:dd:befa
2522c19:dd:c25:c25d:dd:dd:dd:befb/1282c19:dd:c25:c25d:dd:dd:dd:befb
2532c19:dd:c25:c25d:dd:dd:dd:befc/1282c19:dd:c25:c25d:dd:dd:dd:befc
2542c19:dd:c25:c25d:dd:dd:dd:befd/1282c19:dd:c25:c25d:dd:dd:dd:befd
2552c19:dd:c25:c25d:dd:dd:dd:befe/1282c19:dd:c25:c25d:dd:dd:dd:befe
2562c19:dd:c25:c25d:dd:dd:dd:beff/1282c19:dd:c25:c25d:dd:dd:dd:beff

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.