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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:c25:c25d:dd:dd:dd:ca00/119
First address
2c19:dd:c25:c25d:dd:dd:dd:ca00
Last address
2c19:dd:c25:c25d:dd:dd:dd:cbff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:ca00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
a.c.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
b.c.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
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/128
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:c25:c25d:dd:dd:dd:ca00/119 makes 512 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:ca00/1282c19:dd:c25:c25d:dd:dd:dd:ca00
22c19:dd:c25:c25d:dd:dd:dd:ca01/1282c19:dd:c25:c25d:dd:dd:dd:ca01
32c19:dd:c25:c25d:dd:dd:dd:ca02/1282c19:dd:c25:c25d:dd:dd:dd:ca02
42c19:dd:c25:c25d:dd:dd:dd:ca03/1282c19:dd:c25:c25d:dd:dd:dd:ca03
52c19:dd:c25:c25d:dd:dd:dd:ca04/1282c19:dd:c25:c25d:dd:dd:dd:ca04
62c19:dd:c25:c25d:dd:dd:dd:ca05/1282c19:dd:c25:c25d:dd:dd:dd:ca05
72c19:dd:c25:c25d:dd:dd:dd:ca06/1282c19:dd:c25:c25d:dd:dd:dd:ca06
82c19:dd:c25:c25d:dd:dd:dd:ca07/1282c19:dd:c25:c25d:dd:dd:dd:ca07
92c19:dd:c25:c25d:dd:dd:dd:ca08/1282c19:dd:c25:c25d:dd:dd:dd:ca08
102c19:dd:c25:c25d:dd:dd:dd:ca09/1282c19:dd:c25:c25d:dd:dd:dd:ca09
112c19:dd:c25:c25d:dd:dd:dd:ca0a/1282c19:dd:c25:c25d:dd:dd:dd:ca0a
122c19:dd:c25:c25d:dd:dd:dd:ca0b/1282c19:dd:c25:c25d:dd:dd:dd:ca0b
132c19:dd:c25:c25d:dd:dd:dd:ca0c/1282c19:dd:c25:c25d:dd:dd:dd:ca0c
142c19:dd:c25:c25d:dd:dd:dd:ca0d/1282c19:dd:c25:c25d:dd:dd:dd:ca0d
152c19:dd:c25:c25d:dd:dd:dd:ca0e/1282c19:dd:c25:c25d:dd:dd:dd:ca0e
162c19:dd:c25:c25d:dd:dd:dd:ca0f/1282c19:dd:c25:c25d:dd:dd:dd:ca0f
172c19:dd:c25:c25d:dd:dd:dd:ca10/1282c19:dd:c25:c25d:dd:dd:dd:ca10
182c19:dd:c25:c25d:dd:dd:dd:ca11/1282c19:dd:c25:c25d:dd:dd:dd:ca11
192c19:dd:c25:c25d:dd:dd:dd:ca12/1282c19:dd:c25:c25d:dd:dd:dd:ca12
202c19:dd:c25:c25d:dd:dd:dd:ca13/1282c19:dd:c25:c25d:dd:dd:dd:ca13
212c19:dd:c25:c25d:dd:dd:dd:ca14/1282c19:dd:c25:c25d:dd:dd:dd:ca14
222c19:dd:c25:c25d:dd:dd:dd:ca15/1282c19:dd:c25:c25d:dd:dd:dd:ca15
232c19:dd:c25:c25d:dd:dd:dd:ca16/1282c19:dd:c25:c25d:dd:dd:dd:ca16
242c19:dd:c25:c25d:dd:dd:dd:ca17/1282c19:dd:c25:c25d:dd:dd:dd:ca17
252c19:dd:c25:c25d:dd:dd:dd:ca18/1282c19:dd:c25:c25d:dd:dd:dd:ca18
262c19:dd:c25:c25d:dd:dd:dd:ca19/1282c19:dd:c25:c25d:dd:dd:dd:ca19
272c19:dd:c25:c25d:dd:dd:dd:ca1a/1282c19:dd:c25:c25d:dd:dd:dd:ca1a
282c19:dd:c25:c25d:dd:dd:dd:ca1b/1282c19:dd:c25:c25d:dd:dd:dd:ca1b
292c19:dd:c25:c25d:dd:dd:dd:ca1c/1282c19:dd:c25:c25d:dd:dd:dd:ca1c
302c19:dd:c25:c25d:dd:dd:dd:ca1d/1282c19:dd:c25:c25d:dd:dd:dd:ca1d
312c19:dd:c25:c25d:dd:dd:dd:ca1e/1282c19:dd:c25:c25d:dd:dd:dd:ca1e
322c19:dd:c25:c25d:dd:dd:dd:ca1f/1282c19:dd:c25:c25d:dd:dd:dd:ca1f
332c19:dd:c25:c25d:dd:dd:dd:ca20/1282c19:dd:c25:c25d:dd:dd:dd:ca20
342c19:dd:c25:c25d:dd:dd:dd:ca21/1282c19:dd:c25:c25d:dd:dd:dd:ca21
352c19:dd:c25:c25d:dd:dd:dd:ca22/1282c19:dd:c25:c25d:dd:dd:dd:ca22
362c19:dd:c25:c25d:dd:dd:dd:ca23/1282c19:dd:c25:c25d:dd:dd:dd:ca23
372c19:dd:c25:c25d:dd:dd:dd:ca24/1282c19:dd:c25:c25d:dd:dd:dd:ca24
382c19:dd:c25:c25d:dd:dd:dd:ca25/1282c19:dd:c25:c25d:dd:dd:dd:ca25
392c19:dd:c25:c25d:dd:dd:dd:ca26/1282c19:dd:c25:c25d:dd:dd:dd:ca26
402c19:dd:c25:c25d:dd:dd:dd:ca27/1282c19:dd:c25:c25d:dd:dd:dd:ca27
412c19:dd:c25:c25d:dd:dd:dd:ca28/1282c19:dd:c25:c25d:dd:dd:dd:ca28
422c19:dd:c25:c25d:dd:dd:dd:ca29/1282c19:dd:c25:c25d:dd:dd:dd:ca29
432c19:dd:c25:c25d:dd:dd:dd:ca2a/1282c19:dd:c25:c25d:dd:dd:dd:ca2a
442c19:dd:c25:c25d:dd:dd:dd:ca2b/1282c19:dd:c25:c25d:dd:dd:dd:ca2b
452c19:dd:c25:c25d:dd:dd:dd:ca2c/1282c19:dd:c25:c25d:dd:dd:dd:ca2c
462c19:dd:c25:c25d:dd:dd:dd:ca2d/1282c19:dd:c25:c25d:dd:dd:dd:ca2d
472c19:dd:c25:c25d:dd:dd:dd:ca2e/1282c19:dd:c25:c25d:dd:dd:dd:ca2e
482c19:dd:c25:c25d:dd:dd:dd:ca2f/1282c19:dd:c25:c25d:dd:dd:dd:ca2f
492c19:dd:c25:c25d:dd:dd:dd:ca30/1282c19:dd:c25:c25d:dd:dd:dd:ca30
502c19:dd:c25:c25d:dd:dd:dd:ca31/1282c19:dd:c25:c25d:dd:dd:dd:ca31
512c19:dd:c25:c25d:dd:dd:dd:ca32/1282c19:dd:c25:c25d:dd:dd:dd:ca32
522c19:dd:c25:c25d:dd:dd:dd:ca33/1282c19:dd:c25:c25d:dd:dd:dd:ca33
532c19:dd:c25:c25d:dd:dd:dd:ca34/1282c19:dd:c25:c25d:dd:dd:dd:ca34
542c19:dd:c25:c25d:dd:dd:dd:ca35/1282c19:dd:c25:c25d:dd:dd:dd:ca35
552c19:dd:c25:c25d:dd:dd:dd:ca36/1282c19:dd:c25:c25d:dd:dd:dd:ca36
562c19:dd:c25:c25d:dd:dd:dd:ca37/1282c19:dd:c25:c25d:dd:dd:dd:ca37
572c19:dd:c25:c25d:dd:dd:dd:ca38/1282c19:dd:c25:c25d:dd:dd:dd:ca38
582c19:dd:c25:c25d:dd:dd:dd:ca39/1282c19:dd:c25:c25d:dd:dd:dd:ca39
592c19:dd:c25:c25d:dd:dd:dd:ca3a/1282c19:dd:c25:c25d:dd:dd:dd:ca3a
602c19:dd:c25:c25d:dd:dd:dd:ca3b/1282c19:dd:c25:c25d:dd:dd:dd:ca3b
612c19:dd:c25:c25d:dd:dd:dd:ca3c/1282c19:dd:c25:c25d:dd:dd:dd:ca3c
622c19:dd:c25:c25d:dd:dd:dd:ca3d/1282c19:dd:c25:c25d:dd:dd:dd:ca3d
632c19:dd:c25:c25d:dd:dd:dd:ca3e/1282c19:dd:c25:c25d:dd:dd:dd:ca3e
642c19:dd:c25:c25d:dd:dd:dd:ca3f/1282c19:dd:c25:c25d:dd:dd:dd:ca3f
652c19:dd:c25:c25d:dd:dd:dd:ca40/1282c19:dd:c25:c25d:dd:dd:dd:ca40
662c19:dd:c25:c25d:dd:dd:dd:ca41/1282c19:dd:c25:c25d:dd:dd:dd:ca41
672c19:dd:c25:c25d:dd:dd:dd:ca42/1282c19:dd:c25:c25d:dd:dd:dd:ca42
682c19:dd:c25:c25d:dd:dd:dd:ca43/1282c19:dd:c25:c25d:dd:dd:dd:ca43
692c19:dd:c25:c25d:dd:dd:dd:ca44/1282c19:dd:c25:c25d:dd:dd:dd:ca44
702c19:dd:c25:c25d:dd:dd:dd:ca45/1282c19:dd:c25:c25d:dd:dd:dd:ca45
712c19:dd:c25:c25d:dd:dd:dd:ca46/1282c19:dd:c25:c25d:dd:dd:dd:ca46
722c19:dd:c25:c25d:dd:dd:dd:ca47/1282c19:dd:c25:c25d:dd:dd:dd:ca47
732c19:dd:c25:c25d:dd:dd:dd:ca48/1282c19:dd:c25:c25d:dd:dd:dd:ca48
742c19:dd:c25:c25d:dd:dd:dd:ca49/1282c19:dd:c25:c25d:dd:dd:dd:ca49
752c19:dd:c25:c25d:dd:dd:dd:ca4a/1282c19:dd:c25:c25d:dd:dd:dd:ca4a
762c19:dd:c25:c25d:dd:dd:dd:ca4b/1282c19:dd:c25:c25d:dd:dd:dd:ca4b
772c19:dd:c25:c25d:dd:dd:dd:ca4c/1282c19:dd:c25:c25d:dd:dd:dd:ca4c
782c19:dd:c25:c25d:dd:dd:dd:ca4d/1282c19:dd:c25:c25d:dd:dd:dd:ca4d
792c19:dd:c25:c25d:dd:dd:dd:ca4e/1282c19:dd:c25:c25d:dd:dd:dd:ca4e
802c19:dd:c25:c25d:dd:dd:dd:ca4f/1282c19:dd:c25:c25d:dd:dd:dd:ca4f
812c19:dd:c25:c25d:dd:dd:dd:ca50/1282c19:dd:c25:c25d:dd:dd:dd:ca50
822c19:dd:c25:c25d:dd:dd:dd:ca51/1282c19:dd:c25:c25d:dd:dd:dd:ca51
832c19:dd:c25:c25d:dd:dd:dd:ca52/1282c19:dd:c25:c25d:dd:dd:dd:ca52
842c19:dd:c25:c25d:dd:dd:dd:ca53/1282c19:dd:c25:c25d:dd:dd:dd:ca53
852c19:dd:c25:c25d:dd:dd:dd:ca54/1282c19:dd:c25:c25d:dd:dd:dd:ca54
862c19:dd:c25:c25d:dd:dd:dd:ca55/1282c19:dd:c25:c25d:dd:dd:dd:ca55
872c19:dd:c25:c25d:dd:dd:dd:ca56/1282c19:dd:c25:c25d:dd:dd:dd:ca56
882c19:dd:c25:c25d:dd:dd:dd:ca57/1282c19:dd:c25:c25d:dd:dd:dd:ca57
892c19:dd:c25:c25d:dd:dd:dd:ca58/1282c19:dd:c25:c25d:dd:dd:dd:ca58
902c19:dd:c25:c25d:dd:dd:dd:ca59/1282c19:dd:c25:c25d:dd:dd:dd:ca59
912c19:dd:c25:c25d:dd:dd:dd:ca5a/1282c19:dd:c25:c25d:dd:dd:dd:ca5a
922c19:dd:c25:c25d:dd:dd:dd:ca5b/1282c19:dd:c25:c25d:dd:dd:dd:ca5b
932c19:dd:c25:c25d:dd:dd:dd:ca5c/1282c19:dd:c25:c25d:dd:dd:dd:ca5c
942c19:dd:c25:c25d:dd:dd:dd:ca5d/1282c19:dd:c25:c25d:dd:dd:dd:ca5d
952c19:dd:c25:c25d:dd:dd:dd:ca5e/1282c19:dd:c25:c25d:dd:dd:dd:ca5e
962c19:dd:c25:c25d:dd:dd:dd:ca5f/1282c19:dd:c25:c25d:dd:dd:dd:ca5f
972c19:dd:c25:c25d:dd:dd:dd:ca60/1282c19:dd:c25:c25d:dd:dd:dd:ca60
982c19:dd:c25:c25d:dd:dd:dd:ca61/1282c19:dd:c25:c25d:dd:dd:dd:ca61
992c19:dd:c25:c25d:dd:dd:dd:ca62/1282c19:dd:c25:c25d:dd:dd:dd:ca62
1002c19:dd:c25:c25d:dd:dd:dd:ca63/1282c19:dd:c25:c25d:dd:dd:dd:ca63
1012c19:dd:c25:c25d:dd:dd:dd:ca64/1282c19:dd:c25:c25d:dd:dd:dd:ca64
1022c19:dd:c25:c25d:dd:dd:dd:ca65/1282c19:dd:c25:c25d:dd:dd:dd:ca65
1032c19:dd:c25:c25d:dd:dd:dd:ca66/1282c19:dd:c25:c25d:dd:dd:dd:ca66
1042c19:dd:c25:c25d:dd:dd:dd:ca67/1282c19:dd:c25:c25d:dd:dd:dd:ca67
1052c19:dd:c25:c25d:dd:dd:dd:ca68/1282c19:dd:c25:c25d:dd:dd:dd:ca68
1062c19:dd:c25:c25d:dd:dd:dd:ca69/1282c19:dd:c25:c25d:dd:dd:dd:ca69
1072c19:dd:c25:c25d:dd:dd:dd:ca6a/1282c19:dd:c25:c25d:dd:dd:dd:ca6a
1082c19:dd:c25:c25d:dd:dd:dd:ca6b/1282c19:dd:c25:c25d:dd:dd:dd:ca6b
1092c19:dd:c25:c25d:dd:dd:dd:ca6c/1282c19:dd:c25:c25d:dd:dd:dd:ca6c
1102c19:dd:c25:c25d:dd:dd:dd:ca6d/1282c19:dd:c25:c25d:dd:dd:dd:ca6d
1112c19:dd:c25:c25d:dd:dd:dd:ca6e/1282c19:dd:c25:c25d:dd:dd:dd:ca6e
1122c19:dd:c25:c25d:dd:dd:dd:ca6f/1282c19:dd:c25:c25d:dd:dd:dd:ca6f
1132c19:dd:c25:c25d:dd:dd:dd:ca70/1282c19:dd:c25:c25d:dd:dd:dd:ca70
1142c19:dd:c25:c25d:dd:dd:dd:ca71/1282c19:dd:c25:c25d:dd:dd:dd:ca71
1152c19:dd:c25:c25d:dd:dd:dd:ca72/1282c19:dd:c25:c25d:dd:dd:dd:ca72
1162c19:dd:c25:c25d:dd:dd:dd:ca73/1282c19:dd:c25:c25d:dd:dd:dd:ca73
1172c19:dd:c25:c25d:dd:dd:dd:ca74/1282c19:dd:c25:c25d:dd:dd:dd:ca74
1182c19:dd:c25:c25d:dd:dd:dd:ca75/1282c19:dd:c25:c25d:dd:dd:dd:ca75
1192c19:dd:c25:c25d:dd:dd:dd:ca76/1282c19:dd:c25:c25d:dd:dd:dd:ca76
1202c19:dd:c25:c25d:dd:dd:dd:ca77/1282c19:dd:c25:c25d:dd:dd:dd:ca77
1212c19:dd:c25:c25d:dd:dd:dd:ca78/1282c19:dd:c25:c25d:dd:dd:dd:ca78
1222c19:dd:c25:c25d:dd:dd:dd:ca79/1282c19:dd:c25:c25d:dd:dd:dd:ca79
1232c19:dd:c25:c25d:dd:dd:dd:ca7a/1282c19:dd:c25:c25d:dd:dd:dd:ca7a
1242c19:dd:c25:c25d:dd:dd:dd:ca7b/1282c19:dd:c25:c25d:dd:dd:dd:ca7b
1252c19:dd:c25:c25d:dd:dd:dd:ca7c/1282c19:dd:c25:c25d:dd:dd:dd:ca7c
1262c19:dd:c25:c25d:dd:dd:dd:ca7d/1282c19:dd:c25:c25d:dd:dd:dd:ca7d
1272c19:dd:c25:c25d:dd:dd:dd:ca7e/1282c19:dd:c25:c25d:dd:dd:dd:ca7e
1282c19:dd:c25:c25d:dd:dd:dd:ca7f/1282c19:dd:c25:c25d:dd:dd:dd:ca7f
1292c19:dd:c25:c25d:dd:dd:dd:ca80/1282c19:dd:c25:c25d:dd:dd:dd:ca80
1302c19:dd:c25:c25d:dd:dd:dd:ca81/1282c19:dd:c25:c25d:dd:dd:dd:ca81
1312c19:dd:c25:c25d:dd:dd:dd:ca82/1282c19:dd:c25:c25d:dd:dd:dd:ca82
1322c19:dd:c25:c25d:dd:dd:dd:ca83/1282c19:dd:c25:c25d:dd:dd:dd:ca83
1332c19:dd:c25:c25d:dd:dd:dd:ca84/1282c19:dd:c25:c25d:dd:dd:dd:ca84
1342c19:dd:c25:c25d:dd:dd:dd:ca85/1282c19:dd:c25:c25d:dd:dd:dd:ca85
1352c19:dd:c25:c25d:dd:dd:dd:ca86/1282c19:dd:c25:c25d:dd:dd:dd:ca86
1362c19:dd:c25:c25d:dd:dd:dd:ca87/1282c19:dd:c25:c25d:dd:dd:dd:ca87
1372c19:dd:c25:c25d:dd:dd:dd:ca88/1282c19:dd:c25:c25d:dd:dd:dd:ca88
1382c19:dd:c25:c25d:dd:dd:dd:ca89/1282c19:dd:c25:c25d:dd:dd:dd:ca89
1392c19:dd:c25:c25d:dd:dd:dd:ca8a/1282c19:dd:c25:c25d:dd:dd:dd:ca8a
1402c19:dd:c25:c25d:dd:dd:dd:ca8b/1282c19:dd:c25:c25d:dd:dd:dd:ca8b
1412c19:dd:c25:c25d:dd:dd:dd:ca8c/1282c19:dd:c25:c25d:dd:dd:dd:ca8c
1422c19:dd:c25:c25d:dd:dd:dd:ca8d/1282c19:dd:c25:c25d:dd:dd:dd:ca8d
1432c19:dd:c25:c25d:dd:dd:dd:ca8e/1282c19:dd:c25:c25d:dd:dd:dd:ca8e
1442c19:dd:c25:c25d:dd:dd:dd:ca8f/1282c19:dd:c25:c25d:dd:dd:dd:ca8f
1452c19:dd:c25:c25d:dd:dd:dd:ca90/1282c19:dd:c25:c25d:dd:dd:dd:ca90
1462c19:dd:c25:c25d:dd:dd:dd:ca91/1282c19:dd:c25:c25d:dd:dd:dd:ca91
1472c19:dd:c25:c25d:dd:dd:dd:ca92/1282c19:dd:c25:c25d:dd:dd:dd:ca92
1482c19:dd:c25:c25d:dd:dd:dd:ca93/1282c19:dd:c25:c25d:dd:dd:dd:ca93
1492c19:dd:c25:c25d:dd:dd:dd:ca94/1282c19:dd:c25:c25d:dd:dd:dd:ca94
1502c19:dd:c25:c25d:dd:dd:dd:ca95/1282c19:dd:c25:c25d:dd:dd:dd:ca95
1512c19:dd:c25:c25d:dd:dd:dd:ca96/1282c19:dd:c25:c25d:dd:dd:dd:ca96
1522c19:dd:c25:c25d:dd:dd:dd:ca97/1282c19:dd:c25:c25d:dd:dd:dd:ca97
1532c19:dd:c25:c25d:dd:dd:dd:ca98/1282c19:dd:c25:c25d:dd:dd:dd:ca98
1542c19:dd:c25:c25d:dd:dd:dd:ca99/1282c19:dd:c25:c25d:dd:dd:dd:ca99
1552c19:dd:c25:c25d:dd:dd:dd:ca9a/1282c19:dd:c25:c25d:dd:dd:dd:ca9a
1562c19:dd:c25:c25d:dd:dd:dd:ca9b/1282c19:dd:c25:c25d:dd:dd:dd:ca9b
1572c19:dd:c25:c25d:dd:dd:dd:ca9c/1282c19:dd:c25:c25d:dd:dd:dd:ca9c
1582c19:dd:c25:c25d:dd:dd:dd:ca9d/1282c19:dd:c25:c25d:dd:dd:dd:ca9d
1592c19:dd:c25:c25d:dd:dd:dd:ca9e/1282c19:dd:c25:c25d:dd:dd:dd:ca9e
1602c19:dd:c25:c25d:dd:dd:dd:ca9f/1282c19:dd:c25:c25d:dd:dd:dd:ca9f
1612c19:dd:c25:c25d:dd:dd:dd:caa0/1282c19:dd:c25:c25d:dd:dd:dd:caa0
1622c19:dd:c25:c25d:dd:dd:dd:caa1/1282c19:dd:c25:c25d:dd:dd:dd:caa1
1632c19:dd:c25:c25d:dd:dd:dd:caa2/1282c19:dd:c25:c25d:dd:dd:dd:caa2
1642c19:dd:c25:c25d:dd:dd:dd:caa3/1282c19:dd:c25:c25d:dd:dd:dd:caa3
1652c19:dd:c25:c25d:dd:dd:dd:caa4/1282c19:dd:c25:c25d:dd:dd:dd:caa4
1662c19:dd:c25:c25d:dd:dd:dd:caa5/1282c19:dd:c25:c25d:dd:dd:dd:caa5
1672c19:dd:c25:c25d:dd:dd:dd:caa6/1282c19:dd:c25:c25d:dd:dd:dd:caa6
1682c19:dd:c25:c25d:dd:dd:dd:caa7/1282c19:dd:c25:c25d:dd:dd:dd:caa7
1692c19:dd:c25:c25d:dd:dd:dd:caa8/1282c19:dd:c25:c25d:dd:dd:dd:caa8
1702c19:dd:c25:c25d:dd:dd:dd:caa9/1282c19:dd:c25:c25d:dd:dd:dd:caa9
1712c19:dd:c25:c25d:dd:dd:dd:caaa/1282c19:dd:c25:c25d:dd:dd:dd:caaa
1722c19:dd:c25:c25d:dd:dd:dd:caab/1282c19:dd:c25:c25d:dd:dd:dd:caab
1732c19:dd:c25:c25d:dd:dd:dd:caac/1282c19:dd:c25:c25d:dd:dd:dd:caac
1742c19:dd:c25:c25d:dd:dd:dd:caad/1282c19:dd:c25:c25d:dd:dd:dd:caad
1752c19:dd:c25:c25d:dd:dd:dd:caae/1282c19:dd:c25:c25d:dd:dd:dd:caae
1762c19:dd:c25:c25d:dd:dd:dd:caaf/1282c19:dd:c25:c25d:dd:dd:dd:caaf
1772c19:dd:c25:c25d:dd:dd:dd:cab0/1282c19:dd:c25:c25d:dd:dd:dd:cab0
1782c19:dd:c25:c25d:dd:dd:dd:cab1/1282c19:dd:c25:c25d:dd:dd:dd:cab1
1792c19:dd:c25:c25d:dd:dd:dd:cab2/1282c19:dd:c25:c25d:dd:dd:dd:cab2
1802c19:dd:c25:c25d:dd:dd:dd:cab3/1282c19:dd:c25:c25d:dd:dd:dd:cab3
1812c19:dd:c25:c25d:dd:dd:dd:cab4/1282c19:dd:c25:c25d:dd:dd:dd:cab4
1822c19:dd:c25:c25d:dd:dd:dd:cab5/1282c19:dd:c25:c25d:dd:dd:dd:cab5
1832c19:dd:c25:c25d:dd:dd:dd:cab6/1282c19:dd:c25:c25d:dd:dd:dd:cab6
1842c19:dd:c25:c25d:dd:dd:dd:cab7/1282c19:dd:c25:c25d:dd:dd:dd:cab7
1852c19:dd:c25:c25d:dd:dd:dd:cab8/1282c19:dd:c25:c25d:dd:dd:dd:cab8
1862c19:dd:c25:c25d:dd:dd:dd:cab9/1282c19:dd:c25:c25d:dd:dd:dd:cab9
1872c19:dd:c25:c25d:dd:dd:dd:caba/1282c19:dd:c25:c25d:dd:dd:dd:caba
1882c19:dd:c25:c25d:dd:dd:dd:cabb/1282c19:dd:c25:c25d:dd:dd:dd:cabb
1892c19:dd:c25:c25d:dd:dd:dd:cabc/1282c19:dd:c25:c25d:dd:dd:dd:cabc
1902c19:dd:c25:c25d:dd:dd:dd:cabd/1282c19:dd:c25:c25d:dd:dd:dd:cabd
1912c19:dd:c25:c25d:dd:dd:dd:cabe/1282c19:dd:c25:c25d:dd:dd:dd:cabe
1922c19:dd:c25:c25d:dd:dd:dd:cabf/1282c19:dd:c25:c25d:dd:dd:dd:cabf
1932c19:dd:c25:c25d:dd:dd:dd:cac0/1282c19:dd:c25:c25d:dd:dd:dd:cac0
1942c19:dd:c25:c25d:dd:dd:dd:cac1/1282c19:dd:c25:c25d:dd:dd:dd:cac1
1952c19:dd:c25:c25d:dd:dd:dd:cac2/1282c19:dd:c25:c25d:dd:dd:dd:cac2
1962c19:dd:c25:c25d:dd:dd:dd:cac3/1282c19:dd:c25:c25d:dd:dd:dd:cac3
1972c19:dd:c25:c25d:dd:dd:dd:cac4/1282c19:dd:c25:c25d:dd:dd:dd:cac4
1982c19:dd:c25:c25d:dd:dd:dd:cac5/1282c19:dd:c25:c25d:dd:dd:dd:cac5
1992c19:dd:c25:c25d:dd:dd:dd:cac6/1282c19:dd:c25:c25d:dd:dd:dd:cac6
2002c19:dd:c25:c25d:dd:dd:dd:cac7/1282c19:dd:c25:c25d:dd:dd:dd:cac7
2012c19:dd:c25:c25d:dd:dd:dd:cac8/1282c19:dd:c25:c25d:dd:dd:dd:cac8
2022c19:dd:c25:c25d:dd:dd:dd:cac9/1282c19:dd:c25:c25d:dd:dd:dd:cac9
2032c19:dd:c25:c25d:dd:dd:dd:caca/1282c19:dd:c25:c25d:dd:dd:dd:caca
2042c19:dd:c25:c25d:dd:dd:dd:cacb/1282c19:dd:c25:c25d:dd:dd:dd:cacb
2052c19:dd:c25:c25d:dd:dd:dd:cacc/1282c19:dd:c25:c25d:dd:dd:dd:cacc
2062c19:dd:c25:c25d:dd:dd:dd:cacd/1282c19:dd:c25:c25d:dd:dd:dd:cacd
2072c19:dd:c25:c25d:dd:dd:dd:cace/1282c19:dd:c25:c25d:dd:dd:dd:cace
2082c19:dd:c25:c25d:dd:dd:dd:cacf/1282c19:dd:c25:c25d:dd:dd:dd:cacf
2092c19:dd:c25:c25d:dd:dd:dd:cad0/1282c19:dd:c25:c25d:dd:dd:dd:cad0
2102c19:dd:c25:c25d:dd:dd:dd:cad1/1282c19:dd:c25:c25d:dd:dd:dd:cad1
2112c19:dd:c25:c25d:dd:dd:dd:cad2/1282c19:dd:c25:c25d:dd:dd:dd:cad2
2122c19:dd:c25:c25d:dd:dd:dd:cad3/1282c19:dd:c25:c25d:dd:dd:dd:cad3
2132c19:dd:c25:c25d:dd:dd:dd:cad4/1282c19:dd:c25:c25d:dd:dd:dd:cad4
2142c19:dd:c25:c25d:dd:dd:dd:cad5/1282c19:dd:c25:c25d:dd:dd:dd:cad5
2152c19:dd:c25:c25d:dd:dd:dd:cad6/1282c19:dd:c25:c25d:dd:dd:dd:cad6
2162c19:dd:c25:c25d:dd:dd:dd:cad7/1282c19:dd:c25:c25d:dd:dd:dd:cad7
2172c19:dd:c25:c25d:dd:dd:dd:cad8/1282c19:dd:c25:c25d:dd:dd:dd:cad8
2182c19:dd:c25:c25d:dd:dd:dd:cad9/1282c19:dd:c25:c25d:dd:dd:dd:cad9
2192c19:dd:c25:c25d:dd:dd:dd:cada/1282c19:dd:c25:c25d:dd:dd:dd:cada
2202c19:dd:c25:c25d:dd:dd:dd:cadb/1282c19:dd:c25:c25d:dd:dd:dd:cadb
2212c19:dd:c25:c25d:dd:dd:dd:cadc/1282c19:dd:c25:c25d:dd:dd:dd:cadc
2222c19:dd:c25:c25d:dd:dd:dd:cadd/1282c19:dd:c25:c25d:dd:dd:dd:cadd
2232c19:dd:c25:c25d:dd:dd:dd:cade/1282c19:dd:c25:c25d:dd:dd:dd:cade
2242c19:dd:c25:c25d:dd:dd:dd:cadf/1282c19:dd:c25:c25d:dd:dd:dd:cadf
2252c19:dd:c25:c25d:dd:dd:dd:cae0/1282c19:dd:c25:c25d:dd:dd:dd:cae0
2262c19:dd:c25:c25d:dd:dd:dd:cae1/1282c19:dd:c25:c25d:dd:dd:dd:cae1
2272c19:dd:c25:c25d:dd:dd:dd:cae2/1282c19:dd:c25:c25d:dd:dd:dd:cae2
2282c19:dd:c25:c25d:dd:dd:dd:cae3/1282c19:dd:c25:c25d:dd:dd:dd:cae3
2292c19:dd:c25:c25d:dd:dd:dd:cae4/1282c19:dd:c25:c25d:dd:dd:dd:cae4
2302c19:dd:c25:c25d:dd:dd:dd:cae5/1282c19:dd:c25:c25d:dd:dd:dd:cae5
2312c19:dd:c25:c25d:dd:dd:dd:cae6/1282c19:dd:c25:c25d:dd:dd:dd:cae6
2322c19:dd:c25:c25d:dd:dd:dd:cae7/1282c19:dd:c25:c25d:dd:dd:dd:cae7
2332c19:dd:c25:c25d:dd:dd:dd:cae8/1282c19:dd:c25:c25d:dd:dd:dd:cae8
2342c19:dd:c25:c25d:dd:dd:dd:cae9/1282c19:dd:c25:c25d:dd:dd:dd:cae9
2352c19:dd:c25:c25d:dd:dd:dd:caea/1282c19:dd:c25:c25d:dd:dd:dd:caea
2362c19:dd:c25:c25d:dd:dd:dd:caeb/1282c19:dd:c25:c25d:dd:dd:dd:caeb
2372c19:dd:c25:c25d:dd:dd:dd:caec/1282c19:dd:c25:c25d:dd:dd:dd:caec
2382c19:dd:c25:c25d:dd:dd:dd:caed/1282c19:dd:c25:c25d:dd:dd:dd:caed
2392c19:dd:c25:c25d:dd:dd:dd:caee/1282c19:dd:c25:c25d:dd:dd:dd:caee
2402c19:dd:c25:c25d:dd:dd:dd:caef/1282c19:dd:c25:c25d:dd:dd:dd:caef
2412c19:dd:c25:c25d:dd:dd:dd:caf0/1282c19:dd:c25:c25d:dd:dd:dd:caf0
2422c19:dd:c25:c25d:dd:dd:dd:caf1/1282c19:dd:c25:c25d:dd:dd:dd:caf1
2432c19:dd:c25:c25d:dd:dd:dd:caf2/1282c19:dd:c25:c25d:dd:dd:dd:caf2
2442c19:dd:c25:c25d:dd:dd:dd:caf3/1282c19:dd:c25:c25d:dd:dd:dd:caf3
2452c19:dd:c25:c25d:dd:dd:dd:caf4/1282c19:dd:c25:c25d:dd:dd:dd:caf4
2462c19:dd:c25:c25d:dd:dd:dd:caf5/1282c19:dd:c25:c25d:dd:dd:dd:caf5
2472c19:dd:c25:c25d:dd:dd:dd:caf6/1282c19:dd:c25:c25d:dd:dd:dd:caf6
2482c19:dd:c25:c25d:dd:dd:dd:caf7/1282c19:dd:c25:c25d:dd:dd:dd:caf7
2492c19:dd:c25:c25d:dd:dd:dd:caf8/1282c19:dd:c25:c25d:dd:dd:dd:caf8
2502c19:dd:c25:c25d:dd:dd:dd:caf9/1282c19:dd:c25:c25d:dd:dd:dd:caf9
2512c19:dd:c25:c25d:dd:dd:dd:cafa/1282c19:dd:c25:c25d:dd:dd:dd:cafa
2522c19:dd:c25:c25d:dd:dd:dd:cafb/1282c19:dd:c25:c25d:dd:dd:dd:cafb
2532c19:dd:c25:c25d:dd:dd:dd:cafc/1282c19:dd:c25:c25d:dd:dd:dd:cafc
2542c19:dd:c25:c25d:dd:dd:dd:cafd/1282c19:dd:c25:c25d:dd:dd:dd:cafd
2552c19:dd:c25:c25d:dd:dd:dd:cafe/1282c19:dd:c25:c25d:dd:dd:dd:cafe
2562c19:dd:c25:c25d:dd:dd:dd:caff/1282c19:dd:c25:c25d:dd:dd:dd:caff

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.