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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:c25:94de:ef00/120
First address
2c19:dd:d9:dd:c25:c25:94de:ef00
Last address
2c19:dd:d9:dd:c25:c25:94de:efff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:ef00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
f.e.e.d.4.9.5.2.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:c25:94de:ef00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:ef00/1282c19:dd:d9:dd:c25:c25:94de:ef00
22c19:dd:d9:dd:c25:c25:94de:ef01/1282c19:dd:d9:dd:c25:c25:94de:ef01
32c19:dd:d9:dd:c25:c25:94de:ef02/1282c19:dd:d9:dd:c25:c25:94de:ef02
42c19:dd:d9:dd:c25:c25:94de:ef03/1282c19:dd:d9:dd:c25:c25:94de:ef03
52c19:dd:d9:dd:c25:c25:94de:ef04/1282c19:dd:d9:dd:c25:c25:94de:ef04
62c19:dd:d9:dd:c25:c25:94de:ef05/1282c19:dd:d9:dd:c25:c25:94de:ef05
72c19:dd:d9:dd:c25:c25:94de:ef06/1282c19:dd:d9:dd:c25:c25:94de:ef06
82c19:dd:d9:dd:c25:c25:94de:ef07/1282c19:dd:d9:dd:c25:c25:94de:ef07
92c19:dd:d9:dd:c25:c25:94de:ef08/1282c19:dd:d9:dd:c25:c25:94de:ef08
102c19:dd:d9:dd:c25:c25:94de:ef09/1282c19:dd:d9:dd:c25:c25:94de:ef09
112c19:dd:d9:dd:c25:c25:94de:ef0a/1282c19:dd:d9:dd:c25:c25:94de:ef0a
122c19:dd:d9:dd:c25:c25:94de:ef0b/1282c19:dd:d9:dd:c25:c25:94de:ef0b
132c19:dd:d9:dd:c25:c25:94de:ef0c/1282c19:dd:d9:dd:c25:c25:94de:ef0c
142c19:dd:d9:dd:c25:c25:94de:ef0d/1282c19:dd:d9:dd:c25:c25:94de:ef0d
152c19:dd:d9:dd:c25:c25:94de:ef0e/1282c19:dd:d9:dd:c25:c25:94de:ef0e
162c19:dd:d9:dd:c25:c25:94de:ef0f/1282c19:dd:d9:dd:c25:c25:94de:ef0f
172c19:dd:d9:dd:c25:c25:94de:ef10/1282c19:dd:d9:dd:c25:c25:94de:ef10
182c19:dd:d9:dd:c25:c25:94de:ef11/1282c19:dd:d9:dd:c25:c25:94de:ef11
192c19:dd:d9:dd:c25:c25:94de:ef12/1282c19:dd:d9:dd:c25:c25:94de:ef12
202c19:dd:d9:dd:c25:c25:94de:ef13/1282c19:dd:d9:dd:c25:c25:94de:ef13
212c19:dd:d9:dd:c25:c25:94de:ef14/1282c19:dd:d9:dd:c25:c25:94de:ef14
222c19:dd:d9:dd:c25:c25:94de:ef15/1282c19:dd:d9:dd:c25:c25:94de:ef15
232c19:dd:d9:dd:c25:c25:94de:ef16/1282c19:dd:d9:dd:c25:c25:94de:ef16
242c19:dd:d9:dd:c25:c25:94de:ef17/1282c19:dd:d9:dd:c25:c25:94de:ef17
252c19:dd:d9:dd:c25:c25:94de:ef18/1282c19:dd:d9:dd:c25:c25:94de:ef18
262c19:dd:d9:dd:c25:c25:94de:ef19/1282c19:dd:d9:dd:c25:c25:94de:ef19
272c19:dd:d9:dd:c25:c25:94de:ef1a/1282c19:dd:d9:dd:c25:c25:94de:ef1a
282c19:dd:d9:dd:c25:c25:94de:ef1b/1282c19:dd:d9:dd:c25:c25:94de:ef1b
292c19:dd:d9:dd:c25:c25:94de:ef1c/1282c19:dd:d9:dd:c25:c25:94de:ef1c
302c19:dd:d9:dd:c25:c25:94de:ef1d/1282c19:dd:d9:dd:c25:c25:94de:ef1d
312c19:dd:d9:dd:c25:c25:94de:ef1e/1282c19:dd:d9:dd:c25:c25:94de:ef1e
322c19:dd:d9:dd:c25:c25:94de:ef1f/1282c19:dd:d9:dd:c25:c25:94de:ef1f
332c19:dd:d9:dd:c25:c25:94de:ef20/1282c19:dd:d9:dd:c25:c25:94de:ef20
342c19:dd:d9:dd:c25:c25:94de:ef21/1282c19:dd:d9:dd:c25:c25:94de:ef21
352c19:dd:d9:dd:c25:c25:94de:ef22/1282c19:dd:d9:dd:c25:c25:94de:ef22
362c19:dd:d9:dd:c25:c25:94de:ef23/1282c19:dd:d9:dd:c25:c25:94de:ef23
372c19:dd:d9:dd:c25:c25:94de:ef24/1282c19:dd:d9:dd:c25:c25:94de:ef24
382c19:dd:d9:dd:c25:c25:94de:ef25/1282c19:dd:d9:dd:c25:c25:94de:ef25
392c19:dd:d9:dd:c25:c25:94de:ef26/1282c19:dd:d9:dd:c25:c25:94de:ef26
402c19:dd:d9:dd:c25:c25:94de:ef27/1282c19:dd:d9:dd:c25:c25:94de:ef27
412c19:dd:d9:dd:c25:c25:94de:ef28/1282c19:dd:d9:dd:c25:c25:94de:ef28
422c19:dd:d9:dd:c25:c25:94de:ef29/1282c19:dd:d9:dd:c25:c25:94de:ef29
432c19:dd:d9:dd:c25:c25:94de:ef2a/1282c19:dd:d9:dd:c25:c25:94de:ef2a
442c19:dd:d9:dd:c25:c25:94de:ef2b/1282c19:dd:d9:dd:c25:c25:94de:ef2b
452c19:dd:d9:dd:c25:c25:94de:ef2c/1282c19:dd:d9:dd:c25:c25:94de:ef2c
462c19:dd:d9:dd:c25:c25:94de:ef2d/1282c19:dd:d9:dd:c25:c25:94de:ef2d
472c19:dd:d9:dd:c25:c25:94de:ef2e/1282c19:dd:d9:dd:c25:c25:94de:ef2e
482c19:dd:d9:dd:c25:c25:94de:ef2f/1282c19:dd:d9:dd:c25:c25:94de:ef2f
492c19:dd:d9:dd:c25:c25:94de:ef30/1282c19:dd:d9:dd:c25:c25:94de:ef30
502c19:dd:d9:dd:c25:c25:94de:ef31/1282c19:dd:d9:dd:c25:c25:94de:ef31
512c19:dd:d9:dd:c25:c25:94de:ef32/1282c19:dd:d9:dd:c25:c25:94de:ef32
522c19:dd:d9:dd:c25:c25:94de:ef33/1282c19:dd:d9:dd:c25:c25:94de:ef33
532c19:dd:d9:dd:c25:c25:94de:ef34/1282c19:dd:d9:dd:c25:c25:94de:ef34
542c19:dd:d9:dd:c25:c25:94de:ef35/1282c19:dd:d9:dd:c25:c25:94de:ef35
552c19:dd:d9:dd:c25:c25:94de:ef36/1282c19:dd:d9:dd:c25:c25:94de:ef36
562c19:dd:d9:dd:c25:c25:94de:ef37/1282c19:dd:d9:dd:c25:c25:94de:ef37
572c19:dd:d9:dd:c25:c25:94de:ef38/1282c19:dd:d9:dd:c25:c25:94de:ef38
582c19:dd:d9:dd:c25:c25:94de:ef39/1282c19:dd:d9:dd:c25:c25:94de:ef39
592c19:dd:d9:dd:c25:c25:94de:ef3a/1282c19:dd:d9:dd:c25:c25:94de:ef3a
602c19:dd:d9:dd:c25:c25:94de:ef3b/1282c19:dd:d9:dd:c25:c25:94de:ef3b
612c19:dd:d9:dd:c25:c25:94de:ef3c/1282c19:dd:d9:dd:c25:c25:94de:ef3c
622c19:dd:d9:dd:c25:c25:94de:ef3d/1282c19:dd:d9:dd:c25:c25:94de:ef3d
632c19:dd:d9:dd:c25:c25:94de:ef3e/1282c19:dd:d9:dd:c25:c25:94de:ef3e
642c19:dd:d9:dd:c25:c25:94de:ef3f/1282c19:dd:d9:dd:c25:c25:94de:ef3f
652c19:dd:d9:dd:c25:c25:94de:ef40/1282c19:dd:d9:dd:c25:c25:94de:ef40
662c19:dd:d9:dd:c25:c25:94de:ef41/1282c19:dd:d9:dd:c25:c25:94de:ef41
672c19:dd:d9:dd:c25:c25:94de:ef42/1282c19:dd:d9:dd:c25:c25:94de:ef42
682c19:dd:d9:dd:c25:c25:94de:ef43/1282c19:dd:d9:dd:c25:c25:94de:ef43
692c19:dd:d9:dd:c25:c25:94de:ef44/1282c19:dd:d9:dd:c25:c25:94de:ef44
702c19:dd:d9:dd:c25:c25:94de:ef45/1282c19:dd:d9:dd:c25:c25:94de:ef45
712c19:dd:d9:dd:c25:c25:94de:ef46/1282c19:dd:d9:dd:c25:c25:94de:ef46
722c19:dd:d9:dd:c25:c25:94de:ef47/1282c19:dd:d9:dd:c25:c25:94de:ef47
732c19:dd:d9:dd:c25:c25:94de:ef48/1282c19:dd:d9:dd:c25:c25:94de:ef48
742c19:dd:d9:dd:c25:c25:94de:ef49/1282c19:dd:d9:dd:c25:c25:94de:ef49
752c19:dd:d9:dd:c25:c25:94de:ef4a/1282c19:dd:d9:dd:c25:c25:94de:ef4a
762c19:dd:d9:dd:c25:c25:94de:ef4b/1282c19:dd:d9:dd:c25:c25:94de:ef4b
772c19:dd:d9:dd:c25:c25:94de:ef4c/1282c19:dd:d9:dd:c25:c25:94de:ef4c
782c19:dd:d9:dd:c25:c25:94de:ef4d/1282c19:dd:d9:dd:c25:c25:94de:ef4d
792c19:dd:d9:dd:c25:c25:94de:ef4e/1282c19:dd:d9:dd:c25:c25:94de:ef4e
802c19:dd:d9:dd:c25:c25:94de:ef4f/1282c19:dd:d9:dd:c25:c25:94de:ef4f
812c19:dd:d9:dd:c25:c25:94de:ef50/1282c19:dd:d9:dd:c25:c25:94de:ef50
822c19:dd:d9:dd:c25:c25:94de:ef51/1282c19:dd:d9:dd:c25:c25:94de:ef51
832c19:dd:d9:dd:c25:c25:94de:ef52/1282c19:dd:d9:dd:c25:c25:94de:ef52
842c19:dd:d9:dd:c25:c25:94de:ef53/1282c19:dd:d9:dd:c25:c25:94de:ef53
852c19:dd:d9:dd:c25:c25:94de:ef54/1282c19:dd:d9:dd:c25:c25:94de:ef54
862c19:dd:d9:dd:c25:c25:94de:ef55/1282c19:dd:d9:dd:c25:c25:94de:ef55
872c19:dd:d9:dd:c25:c25:94de:ef56/1282c19:dd:d9:dd:c25:c25:94de:ef56
882c19:dd:d9:dd:c25:c25:94de:ef57/1282c19:dd:d9:dd:c25:c25:94de:ef57
892c19:dd:d9:dd:c25:c25:94de:ef58/1282c19:dd:d9:dd:c25:c25:94de:ef58
902c19:dd:d9:dd:c25:c25:94de:ef59/1282c19:dd:d9:dd:c25:c25:94de:ef59
912c19:dd:d9:dd:c25:c25:94de:ef5a/1282c19:dd:d9:dd:c25:c25:94de:ef5a
922c19:dd:d9:dd:c25:c25:94de:ef5b/1282c19:dd:d9:dd:c25:c25:94de:ef5b
932c19:dd:d9:dd:c25:c25:94de:ef5c/1282c19:dd:d9:dd:c25:c25:94de:ef5c
942c19:dd:d9:dd:c25:c25:94de:ef5d/1282c19:dd:d9:dd:c25:c25:94de:ef5d
952c19:dd:d9:dd:c25:c25:94de:ef5e/1282c19:dd:d9:dd:c25:c25:94de:ef5e
962c19:dd:d9:dd:c25:c25:94de:ef5f/1282c19:dd:d9:dd:c25:c25:94de:ef5f
972c19:dd:d9:dd:c25:c25:94de:ef60/1282c19:dd:d9:dd:c25:c25:94de:ef60
982c19:dd:d9:dd:c25:c25:94de:ef61/1282c19:dd:d9:dd:c25:c25:94de:ef61
992c19:dd:d9:dd:c25:c25:94de:ef62/1282c19:dd:d9:dd:c25:c25:94de:ef62
1002c19:dd:d9:dd:c25:c25:94de:ef63/1282c19:dd:d9:dd:c25:c25:94de:ef63
1012c19:dd:d9:dd:c25:c25:94de:ef64/1282c19:dd:d9:dd:c25:c25:94de:ef64
1022c19:dd:d9:dd:c25:c25:94de:ef65/1282c19:dd:d9:dd:c25:c25:94de:ef65
1032c19:dd:d9:dd:c25:c25:94de:ef66/1282c19:dd:d9:dd:c25:c25:94de:ef66
1042c19:dd:d9:dd:c25:c25:94de:ef67/1282c19:dd:d9:dd:c25:c25:94de:ef67
1052c19:dd:d9:dd:c25:c25:94de:ef68/1282c19:dd:d9:dd:c25:c25:94de:ef68
1062c19:dd:d9:dd:c25:c25:94de:ef69/1282c19:dd:d9:dd:c25:c25:94de:ef69
1072c19:dd:d9:dd:c25:c25:94de:ef6a/1282c19:dd:d9:dd:c25:c25:94de:ef6a
1082c19:dd:d9:dd:c25:c25:94de:ef6b/1282c19:dd:d9:dd:c25:c25:94de:ef6b
1092c19:dd:d9:dd:c25:c25:94de:ef6c/1282c19:dd:d9:dd:c25:c25:94de:ef6c
1102c19:dd:d9:dd:c25:c25:94de:ef6d/1282c19:dd:d9:dd:c25:c25:94de:ef6d
1112c19:dd:d9:dd:c25:c25:94de:ef6e/1282c19:dd:d9:dd:c25:c25:94de:ef6e
1122c19:dd:d9:dd:c25:c25:94de:ef6f/1282c19:dd:d9:dd:c25:c25:94de:ef6f
1132c19:dd:d9:dd:c25:c25:94de:ef70/1282c19:dd:d9:dd:c25:c25:94de:ef70
1142c19:dd:d9:dd:c25:c25:94de:ef71/1282c19:dd:d9:dd:c25:c25:94de:ef71
1152c19:dd:d9:dd:c25:c25:94de:ef72/1282c19:dd:d9:dd:c25:c25:94de:ef72
1162c19:dd:d9:dd:c25:c25:94de:ef73/1282c19:dd:d9:dd:c25:c25:94de:ef73
1172c19:dd:d9:dd:c25:c25:94de:ef74/1282c19:dd:d9:dd:c25:c25:94de:ef74
1182c19:dd:d9:dd:c25:c25:94de:ef75/1282c19:dd:d9:dd:c25:c25:94de:ef75
1192c19:dd:d9:dd:c25:c25:94de:ef76/1282c19:dd:d9:dd:c25:c25:94de:ef76
1202c19:dd:d9:dd:c25:c25:94de:ef77/1282c19:dd:d9:dd:c25:c25:94de:ef77
1212c19:dd:d9:dd:c25:c25:94de:ef78/1282c19:dd:d9:dd:c25:c25:94de:ef78
1222c19:dd:d9:dd:c25:c25:94de:ef79/1282c19:dd:d9:dd:c25:c25:94de:ef79
1232c19:dd:d9:dd:c25:c25:94de:ef7a/1282c19:dd:d9:dd:c25:c25:94de:ef7a
1242c19:dd:d9:dd:c25:c25:94de:ef7b/1282c19:dd:d9:dd:c25:c25:94de:ef7b
1252c19:dd:d9:dd:c25:c25:94de:ef7c/1282c19:dd:d9:dd:c25:c25:94de:ef7c
1262c19:dd:d9:dd:c25:c25:94de:ef7d/1282c19:dd:d9:dd:c25:c25:94de:ef7d
1272c19:dd:d9:dd:c25:c25:94de:ef7e/1282c19:dd:d9:dd:c25:c25:94de:ef7e
1282c19:dd:d9:dd:c25:c25:94de:ef7f/1282c19:dd:d9:dd:c25:c25:94de:ef7f
1292c19:dd:d9:dd:c25:c25:94de:ef80/1282c19:dd:d9:dd:c25:c25:94de:ef80
1302c19:dd:d9:dd:c25:c25:94de:ef81/1282c19:dd:d9:dd:c25:c25:94de:ef81
1312c19:dd:d9:dd:c25:c25:94de:ef82/1282c19:dd:d9:dd:c25:c25:94de:ef82
1322c19:dd:d9:dd:c25:c25:94de:ef83/1282c19:dd:d9:dd:c25:c25:94de:ef83
1332c19:dd:d9:dd:c25:c25:94de:ef84/1282c19:dd:d9:dd:c25:c25:94de:ef84
1342c19:dd:d9:dd:c25:c25:94de:ef85/1282c19:dd:d9:dd:c25:c25:94de:ef85
1352c19:dd:d9:dd:c25:c25:94de:ef86/1282c19:dd:d9:dd:c25:c25:94de:ef86
1362c19:dd:d9:dd:c25:c25:94de:ef87/1282c19:dd:d9:dd:c25:c25:94de:ef87
1372c19:dd:d9:dd:c25:c25:94de:ef88/1282c19:dd:d9:dd:c25:c25:94de:ef88
1382c19:dd:d9:dd:c25:c25:94de:ef89/1282c19:dd:d9:dd:c25:c25:94de:ef89
1392c19:dd:d9:dd:c25:c25:94de:ef8a/1282c19:dd:d9:dd:c25:c25:94de:ef8a
1402c19:dd:d9:dd:c25:c25:94de:ef8b/1282c19:dd:d9:dd:c25:c25:94de:ef8b
1412c19:dd:d9:dd:c25:c25:94de:ef8c/1282c19:dd:d9:dd:c25:c25:94de:ef8c
1422c19:dd:d9:dd:c25:c25:94de:ef8d/1282c19:dd:d9:dd:c25:c25:94de:ef8d
1432c19:dd:d9:dd:c25:c25:94de:ef8e/1282c19:dd:d9:dd:c25:c25:94de:ef8e
1442c19:dd:d9:dd:c25:c25:94de:ef8f/1282c19:dd:d9:dd:c25:c25:94de:ef8f
1452c19:dd:d9:dd:c25:c25:94de:ef90/1282c19:dd:d9:dd:c25:c25:94de:ef90
1462c19:dd:d9:dd:c25:c25:94de:ef91/1282c19:dd:d9:dd:c25:c25:94de:ef91
1472c19:dd:d9:dd:c25:c25:94de:ef92/1282c19:dd:d9:dd:c25:c25:94de:ef92
1482c19:dd:d9:dd:c25:c25:94de:ef93/1282c19:dd:d9:dd:c25:c25:94de:ef93
1492c19:dd:d9:dd:c25:c25:94de:ef94/1282c19:dd:d9:dd:c25:c25:94de:ef94
1502c19:dd:d9:dd:c25:c25:94de:ef95/1282c19:dd:d9:dd:c25:c25:94de:ef95
1512c19:dd:d9:dd:c25:c25:94de:ef96/1282c19:dd:d9:dd:c25:c25:94de:ef96
1522c19:dd:d9:dd:c25:c25:94de:ef97/1282c19:dd:d9:dd:c25:c25:94de:ef97
1532c19:dd:d9:dd:c25:c25:94de:ef98/1282c19:dd:d9:dd:c25:c25:94de:ef98
1542c19:dd:d9:dd:c25:c25:94de:ef99/1282c19:dd:d9:dd:c25:c25:94de:ef99
1552c19:dd:d9:dd:c25:c25:94de:ef9a/1282c19:dd:d9:dd:c25:c25:94de:ef9a
1562c19:dd:d9:dd:c25:c25:94de:ef9b/1282c19:dd:d9:dd:c25:c25:94de:ef9b
1572c19:dd:d9:dd:c25:c25:94de:ef9c/1282c19:dd:d9:dd:c25:c25:94de:ef9c
1582c19:dd:d9:dd:c25:c25:94de:ef9d/1282c19:dd:d9:dd:c25:c25:94de:ef9d
1592c19:dd:d9:dd:c25:c25:94de:ef9e/1282c19:dd:d9:dd:c25:c25:94de:ef9e
1602c19:dd:d9:dd:c25:c25:94de:ef9f/1282c19:dd:d9:dd:c25:c25:94de:ef9f
1612c19:dd:d9:dd:c25:c25:94de:efa0/1282c19:dd:d9:dd:c25:c25:94de:efa0
1622c19:dd:d9:dd:c25:c25:94de:efa1/1282c19:dd:d9:dd:c25:c25:94de:efa1
1632c19:dd:d9:dd:c25:c25:94de:efa2/1282c19:dd:d9:dd:c25:c25:94de:efa2
1642c19:dd:d9:dd:c25:c25:94de:efa3/1282c19:dd:d9:dd:c25:c25:94de:efa3
1652c19:dd:d9:dd:c25:c25:94de:efa4/1282c19:dd:d9:dd:c25:c25:94de:efa4
1662c19:dd:d9:dd:c25:c25:94de:efa5/1282c19:dd:d9:dd:c25:c25:94de:efa5
1672c19:dd:d9:dd:c25:c25:94de:efa6/1282c19:dd:d9:dd:c25:c25:94de:efa6
1682c19:dd:d9:dd:c25:c25:94de:efa7/1282c19:dd:d9:dd:c25:c25:94de:efa7
1692c19:dd:d9:dd:c25:c25:94de:efa8/1282c19:dd:d9:dd:c25:c25:94de:efa8
1702c19:dd:d9:dd:c25:c25:94de:efa9/1282c19:dd:d9:dd:c25:c25:94de:efa9
1712c19:dd:d9:dd:c25:c25:94de:efaa/1282c19:dd:d9:dd:c25:c25:94de:efaa
1722c19:dd:d9:dd:c25:c25:94de:efab/1282c19:dd:d9:dd:c25:c25:94de:efab
1732c19:dd:d9:dd:c25:c25:94de:efac/1282c19:dd:d9:dd:c25:c25:94de:efac
1742c19:dd:d9:dd:c25:c25:94de:efad/1282c19:dd:d9:dd:c25:c25:94de:efad
1752c19:dd:d9:dd:c25:c25:94de:efae/1282c19:dd:d9:dd:c25:c25:94de:efae
1762c19:dd:d9:dd:c25:c25:94de:efaf/1282c19:dd:d9:dd:c25:c25:94de:efaf
1772c19:dd:d9:dd:c25:c25:94de:efb0/1282c19:dd:d9:dd:c25:c25:94de:efb0
1782c19:dd:d9:dd:c25:c25:94de:efb1/1282c19:dd:d9:dd:c25:c25:94de:efb1
1792c19:dd:d9:dd:c25:c25:94de:efb2/1282c19:dd:d9:dd:c25:c25:94de:efb2
1802c19:dd:d9:dd:c25:c25:94de:efb3/1282c19:dd:d9:dd:c25:c25:94de:efb3
1812c19:dd:d9:dd:c25:c25:94de:efb4/1282c19:dd:d9:dd:c25:c25:94de:efb4
1822c19:dd:d9:dd:c25:c25:94de:efb5/1282c19:dd:d9:dd:c25:c25:94de:efb5
1832c19:dd:d9:dd:c25:c25:94de:efb6/1282c19:dd:d9:dd:c25:c25:94de:efb6
1842c19:dd:d9:dd:c25:c25:94de:efb7/1282c19:dd:d9:dd:c25:c25:94de:efb7
1852c19:dd:d9:dd:c25:c25:94de:efb8/1282c19:dd:d9:dd:c25:c25:94de:efb8
1862c19:dd:d9:dd:c25:c25:94de:efb9/1282c19:dd:d9:dd:c25:c25:94de:efb9
1872c19:dd:d9:dd:c25:c25:94de:efba/1282c19:dd:d9:dd:c25:c25:94de:efba
1882c19:dd:d9:dd:c25:c25:94de:efbb/1282c19:dd:d9:dd:c25:c25:94de:efbb
1892c19:dd:d9:dd:c25:c25:94de:efbc/1282c19:dd:d9:dd:c25:c25:94de:efbc
1902c19:dd:d9:dd:c25:c25:94de:efbd/1282c19:dd:d9:dd:c25:c25:94de:efbd
1912c19:dd:d9:dd:c25:c25:94de:efbe/1282c19:dd:d9:dd:c25:c25:94de:efbe
1922c19:dd:d9:dd:c25:c25:94de:efbf/1282c19:dd:d9:dd:c25:c25:94de:efbf
1932c19:dd:d9:dd:c25:c25:94de:efc0/1282c19:dd:d9:dd:c25:c25:94de:efc0
1942c19:dd:d9:dd:c25:c25:94de:efc1/1282c19:dd:d9:dd:c25:c25:94de:efc1
1952c19:dd:d9:dd:c25:c25:94de:efc2/1282c19:dd:d9:dd:c25:c25:94de:efc2
1962c19:dd:d9:dd:c25:c25:94de:efc3/1282c19:dd:d9:dd:c25:c25:94de:efc3
1972c19:dd:d9:dd:c25:c25:94de:efc4/1282c19:dd:d9:dd:c25:c25:94de:efc4
1982c19:dd:d9:dd:c25:c25:94de:efc5/1282c19:dd:d9:dd:c25:c25:94de:efc5
1992c19:dd:d9:dd:c25:c25:94de:efc6/1282c19:dd:d9:dd:c25:c25:94de:efc6
2002c19:dd:d9:dd:c25:c25:94de:efc7/1282c19:dd:d9:dd:c25:c25:94de:efc7
2012c19:dd:d9:dd:c25:c25:94de:efc8/1282c19:dd:d9:dd:c25:c25:94de:efc8
2022c19:dd:d9:dd:c25:c25:94de:efc9/1282c19:dd:d9:dd:c25:c25:94de:efc9
2032c19:dd:d9:dd:c25:c25:94de:efca/1282c19:dd:d9:dd:c25:c25:94de:efca
2042c19:dd:d9:dd:c25:c25:94de:efcb/1282c19:dd:d9:dd:c25:c25:94de:efcb
2052c19:dd:d9:dd:c25:c25:94de:efcc/1282c19:dd:d9:dd:c25:c25:94de:efcc
2062c19:dd:d9:dd:c25:c25:94de:efcd/1282c19:dd:d9:dd:c25:c25:94de:efcd
2072c19:dd:d9:dd:c25:c25:94de:efce/1282c19:dd:d9:dd:c25:c25:94de:efce
2082c19:dd:d9:dd:c25:c25:94de:efcf/1282c19:dd:d9:dd:c25:c25:94de:efcf
2092c19:dd:d9:dd:c25:c25:94de:efd0/1282c19:dd:d9:dd:c25:c25:94de:efd0
2102c19:dd:d9:dd:c25:c25:94de:efd1/1282c19:dd:d9:dd:c25:c25:94de:efd1
2112c19:dd:d9:dd:c25:c25:94de:efd2/1282c19:dd:d9:dd:c25:c25:94de:efd2
2122c19:dd:d9:dd:c25:c25:94de:efd3/1282c19:dd:d9:dd:c25:c25:94de:efd3
2132c19:dd:d9:dd:c25:c25:94de:efd4/1282c19:dd:d9:dd:c25:c25:94de:efd4
2142c19:dd:d9:dd:c25:c25:94de:efd5/1282c19:dd:d9:dd:c25:c25:94de:efd5
2152c19:dd:d9:dd:c25:c25:94de:efd6/1282c19:dd:d9:dd:c25:c25:94de:efd6
2162c19:dd:d9:dd:c25:c25:94de:efd7/1282c19:dd:d9:dd:c25:c25:94de:efd7
2172c19:dd:d9:dd:c25:c25:94de:efd8/1282c19:dd:d9:dd:c25:c25:94de:efd8
2182c19:dd:d9:dd:c25:c25:94de:efd9/1282c19:dd:d9:dd:c25:c25:94de:efd9
2192c19:dd:d9:dd:c25:c25:94de:efda/1282c19:dd:d9:dd:c25:c25:94de:efda
2202c19:dd:d9:dd:c25:c25:94de:efdb/1282c19:dd:d9:dd:c25:c25:94de:efdb
2212c19:dd:d9:dd:c25:c25:94de:efdc/1282c19:dd:d9:dd:c25:c25:94de:efdc
2222c19:dd:d9:dd:c25:c25:94de:efdd/1282c19:dd:d9:dd:c25:c25:94de:efdd
2232c19:dd:d9:dd:c25:c25:94de:efde/1282c19:dd:d9:dd:c25:c25:94de:efde
2242c19:dd:d9:dd:c25:c25:94de:efdf/1282c19:dd:d9:dd:c25:c25:94de:efdf
2252c19:dd:d9:dd:c25:c25:94de:efe0/1282c19:dd:d9:dd:c25:c25:94de:efe0
2262c19:dd:d9:dd:c25:c25:94de:efe1/1282c19:dd:d9:dd:c25:c25:94de:efe1
2272c19:dd:d9:dd:c25:c25:94de:efe2/1282c19:dd:d9:dd:c25:c25:94de:efe2
2282c19:dd:d9:dd:c25:c25:94de:efe3/1282c19:dd:d9:dd:c25:c25:94de:efe3
2292c19:dd:d9:dd:c25:c25:94de:efe4/1282c19:dd:d9:dd:c25:c25:94de:efe4
2302c19:dd:d9:dd:c25:c25:94de:efe5/1282c19:dd:d9:dd:c25:c25:94de:efe5
2312c19:dd:d9:dd:c25:c25:94de:efe6/1282c19:dd:d9:dd:c25:c25:94de:efe6
2322c19:dd:d9:dd:c25:c25:94de:efe7/1282c19:dd:d9:dd:c25:c25:94de:efe7
2332c19:dd:d9:dd:c25:c25:94de:efe8/1282c19:dd:d9:dd:c25:c25:94de:efe8
2342c19:dd:d9:dd:c25:c25:94de:efe9/1282c19:dd:d9:dd:c25:c25:94de:efe9
2352c19:dd:d9:dd:c25:c25:94de:efea/1282c19:dd:d9:dd:c25:c25:94de:efea
2362c19:dd:d9:dd:c25:c25:94de:efeb/1282c19:dd:d9:dd:c25:c25:94de:efeb
2372c19:dd:d9:dd:c25:c25:94de:efec/1282c19:dd:d9:dd:c25:c25:94de:efec
2382c19:dd:d9:dd:c25:c25:94de:efed/1282c19:dd:d9:dd:c25:c25:94de:efed
2392c19:dd:d9:dd:c25:c25:94de:efee/1282c19:dd:d9:dd:c25:c25:94de:efee
2402c19:dd:d9:dd:c25:c25:94de:efef/1282c19:dd:d9:dd:c25:c25:94de:efef
2412c19:dd:d9:dd:c25:c25:94de:eff0/1282c19:dd:d9:dd:c25:c25:94de:eff0
2422c19:dd:d9:dd:c25:c25:94de:eff1/1282c19:dd:d9:dd:c25:c25:94de:eff1
2432c19:dd:d9:dd:c25:c25:94de:eff2/1282c19:dd:d9:dd:c25:c25:94de:eff2
2442c19:dd:d9:dd:c25:c25:94de:eff3/1282c19:dd:d9:dd:c25:c25:94de:eff3
2452c19:dd:d9:dd:c25:c25:94de:eff4/1282c19:dd:d9:dd:c25:c25:94de:eff4
2462c19:dd:d9:dd:c25:c25:94de:eff5/1282c19:dd:d9:dd:c25:c25:94de:eff5
2472c19:dd:d9:dd:c25:c25:94de:eff6/1282c19:dd:d9:dd:c25:c25:94de:eff6
2482c19:dd:d9:dd:c25:c25:94de:eff7/1282c19:dd:d9:dd:c25:c25:94de:eff7
2492c19:dd:d9:dd:c25:c25:94de:eff8/1282c19:dd:d9:dd:c25:c25:94de:eff8
2502c19:dd:d9:dd:c25:c25:94de:eff9/1282c19:dd:d9:dd:c25:c25:94de:eff9
2512c19:dd:d9:dd:c25:c25:94de:effa/1282c19:dd:d9:dd:c25:c25:94de:effa
2522c19:dd:d9:dd:c25:c25:94de:effb/1282c19:dd:d9:dd:c25:c25:94de:effb
2532c19:dd:d9:dd:c25:c25:94de:effc/1282c19:dd:d9:dd:c25:c25:94de:effc
2542c19:dd:d9:dd:c25:c25:94de:effd/1282c19:dd:d9:dd:c25:c25:94de:effd
2552c19:dd:d9:dd:c25:c25:94de:effe/1282c19:dd:d9:dd:c25:c25:94de:effe
2562c19:dd:d9:dd:c25:c25:94de:efff/1282c19:dd:d9:dd:c25:c25:94de:efff

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.