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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:cc00/119
First address
2c19:dd:c25:c25d:dd:dd:dd:cc00
Last address
2c19:dd:c25:c25d:dd:dd:dd:cdff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:cc00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
c.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
d.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:cc00/119 makes 512 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:cc00/1282c19:dd:c25:c25d:dd:dd:dd:cc00
22c19:dd:c25:c25d:dd:dd:dd:cc01/1282c19:dd:c25:c25d:dd:dd:dd:cc01
32c19:dd:c25:c25d:dd:dd:dd:cc02/1282c19:dd:c25:c25d:dd:dd:dd:cc02
42c19:dd:c25:c25d:dd:dd:dd:cc03/1282c19:dd:c25:c25d:dd:dd:dd:cc03
52c19:dd:c25:c25d:dd:dd:dd:cc04/1282c19:dd:c25:c25d:dd:dd:dd:cc04
62c19:dd:c25:c25d:dd:dd:dd:cc05/1282c19:dd:c25:c25d:dd:dd:dd:cc05
72c19:dd:c25:c25d:dd:dd:dd:cc06/1282c19:dd:c25:c25d:dd:dd:dd:cc06
82c19:dd:c25:c25d:dd:dd:dd:cc07/1282c19:dd:c25:c25d:dd:dd:dd:cc07
92c19:dd:c25:c25d:dd:dd:dd:cc08/1282c19:dd:c25:c25d:dd:dd:dd:cc08
102c19:dd:c25:c25d:dd:dd:dd:cc09/1282c19:dd:c25:c25d:dd:dd:dd:cc09
112c19:dd:c25:c25d:dd:dd:dd:cc0a/1282c19:dd:c25:c25d:dd:dd:dd:cc0a
122c19:dd:c25:c25d:dd:dd:dd:cc0b/1282c19:dd:c25:c25d:dd:dd:dd:cc0b
132c19:dd:c25:c25d:dd:dd:dd:cc0c/1282c19:dd:c25:c25d:dd:dd:dd:cc0c
142c19:dd:c25:c25d:dd:dd:dd:cc0d/1282c19:dd:c25:c25d:dd:dd:dd:cc0d
152c19:dd:c25:c25d:dd:dd:dd:cc0e/1282c19:dd:c25:c25d:dd:dd:dd:cc0e
162c19:dd:c25:c25d:dd:dd:dd:cc0f/1282c19:dd:c25:c25d:dd:dd:dd:cc0f
172c19:dd:c25:c25d:dd:dd:dd:cc10/1282c19:dd:c25:c25d:dd:dd:dd:cc10
182c19:dd:c25:c25d:dd:dd:dd:cc11/1282c19:dd:c25:c25d:dd:dd:dd:cc11
192c19:dd:c25:c25d:dd:dd:dd:cc12/1282c19:dd:c25:c25d:dd:dd:dd:cc12
202c19:dd:c25:c25d:dd:dd:dd:cc13/1282c19:dd:c25:c25d:dd:dd:dd:cc13
212c19:dd:c25:c25d:dd:dd:dd:cc14/1282c19:dd:c25:c25d:dd:dd:dd:cc14
222c19:dd:c25:c25d:dd:dd:dd:cc15/1282c19:dd:c25:c25d:dd:dd:dd:cc15
232c19:dd:c25:c25d:dd:dd:dd:cc16/1282c19:dd:c25:c25d:dd:dd:dd:cc16
242c19:dd:c25:c25d:dd:dd:dd:cc17/1282c19:dd:c25:c25d:dd:dd:dd:cc17
252c19:dd:c25:c25d:dd:dd:dd:cc18/1282c19:dd:c25:c25d:dd:dd:dd:cc18
262c19:dd:c25:c25d:dd:dd:dd:cc19/1282c19:dd:c25:c25d:dd:dd:dd:cc19
272c19:dd:c25:c25d:dd:dd:dd:cc1a/1282c19:dd:c25:c25d:dd:dd:dd:cc1a
282c19:dd:c25:c25d:dd:dd:dd:cc1b/1282c19:dd:c25:c25d:dd:dd:dd:cc1b
292c19:dd:c25:c25d:dd:dd:dd:cc1c/1282c19:dd:c25:c25d:dd:dd:dd:cc1c
302c19:dd:c25:c25d:dd:dd:dd:cc1d/1282c19:dd:c25:c25d:dd:dd:dd:cc1d
312c19:dd:c25:c25d:dd:dd:dd:cc1e/1282c19:dd:c25:c25d:dd:dd:dd:cc1e
322c19:dd:c25:c25d:dd:dd:dd:cc1f/1282c19:dd:c25:c25d:dd:dd:dd:cc1f
332c19:dd:c25:c25d:dd:dd:dd:cc20/1282c19:dd:c25:c25d:dd:dd:dd:cc20
342c19:dd:c25:c25d:dd:dd:dd:cc21/1282c19:dd:c25:c25d:dd:dd:dd:cc21
352c19:dd:c25:c25d:dd:dd:dd:cc22/1282c19:dd:c25:c25d:dd:dd:dd:cc22
362c19:dd:c25:c25d:dd:dd:dd:cc23/1282c19:dd:c25:c25d:dd:dd:dd:cc23
372c19:dd:c25:c25d:dd:dd:dd:cc24/1282c19:dd:c25:c25d:dd:dd:dd:cc24
382c19:dd:c25:c25d:dd:dd:dd:cc25/1282c19:dd:c25:c25d:dd:dd:dd:cc25
392c19:dd:c25:c25d:dd:dd:dd:cc26/1282c19:dd:c25:c25d:dd:dd:dd:cc26
402c19:dd:c25:c25d:dd:dd:dd:cc27/1282c19:dd:c25:c25d:dd:dd:dd:cc27
412c19:dd:c25:c25d:dd:dd:dd:cc28/1282c19:dd:c25:c25d:dd:dd:dd:cc28
422c19:dd:c25:c25d:dd:dd:dd:cc29/1282c19:dd:c25:c25d:dd:dd:dd:cc29
432c19:dd:c25:c25d:dd:dd:dd:cc2a/1282c19:dd:c25:c25d:dd:dd:dd:cc2a
442c19:dd:c25:c25d:dd:dd:dd:cc2b/1282c19:dd:c25:c25d:dd:dd:dd:cc2b
452c19:dd:c25:c25d:dd:dd:dd:cc2c/1282c19:dd:c25:c25d:dd:dd:dd:cc2c
462c19:dd:c25:c25d:dd:dd:dd:cc2d/1282c19:dd:c25:c25d:dd:dd:dd:cc2d
472c19:dd:c25:c25d:dd:dd:dd:cc2e/1282c19:dd:c25:c25d:dd:dd:dd:cc2e
482c19:dd:c25:c25d:dd:dd:dd:cc2f/1282c19:dd:c25:c25d:dd:dd:dd:cc2f
492c19:dd:c25:c25d:dd:dd:dd:cc30/1282c19:dd:c25:c25d:dd:dd:dd:cc30
502c19:dd:c25:c25d:dd:dd:dd:cc31/1282c19:dd:c25:c25d:dd:dd:dd:cc31
512c19:dd:c25:c25d:dd:dd:dd:cc32/1282c19:dd:c25:c25d:dd:dd:dd:cc32
522c19:dd:c25:c25d:dd:dd:dd:cc33/1282c19:dd:c25:c25d:dd:dd:dd:cc33
532c19:dd:c25:c25d:dd:dd:dd:cc34/1282c19:dd:c25:c25d:dd:dd:dd:cc34
542c19:dd:c25:c25d:dd:dd:dd:cc35/1282c19:dd:c25:c25d:dd:dd:dd:cc35
552c19:dd:c25:c25d:dd:dd:dd:cc36/1282c19:dd:c25:c25d:dd:dd:dd:cc36
562c19:dd:c25:c25d:dd:dd:dd:cc37/1282c19:dd:c25:c25d:dd:dd:dd:cc37
572c19:dd:c25:c25d:dd:dd:dd:cc38/1282c19:dd:c25:c25d:dd:dd:dd:cc38
582c19:dd:c25:c25d:dd:dd:dd:cc39/1282c19:dd:c25:c25d:dd:dd:dd:cc39
592c19:dd:c25:c25d:dd:dd:dd:cc3a/1282c19:dd:c25:c25d:dd:dd:dd:cc3a
602c19:dd:c25:c25d:dd:dd:dd:cc3b/1282c19:dd:c25:c25d:dd:dd:dd:cc3b
612c19:dd:c25:c25d:dd:dd:dd:cc3c/1282c19:dd:c25:c25d:dd:dd:dd:cc3c
622c19:dd:c25:c25d:dd:dd:dd:cc3d/1282c19:dd:c25:c25d:dd:dd:dd:cc3d
632c19:dd:c25:c25d:dd:dd:dd:cc3e/1282c19:dd:c25:c25d:dd:dd:dd:cc3e
642c19:dd:c25:c25d:dd:dd:dd:cc3f/1282c19:dd:c25:c25d:dd:dd:dd:cc3f
652c19:dd:c25:c25d:dd:dd:dd:cc40/1282c19:dd:c25:c25d:dd:dd:dd:cc40
662c19:dd:c25:c25d:dd:dd:dd:cc41/1282c19:dd:c25:c25d:dd:dd:dd:cc41
672c19:dd:c25:c25d:dd:dd:dd:cc42/1282c19:dd:c25:c25d:dd:dd:dd:cc42
682c19:dd:c25:c25d:dd:dd:dd:cc43/1282c19:dd:c25:c25d:dd:dd:dd:cc43
692c19:dd:c25:c25d:dd:dd:dd:cc44/1282c19:dd:c25:c25d:dd:dd:dd:cc44
702c19:dd:c25:c25d:dd:dd:dd:cc45/1282c19:dd:c25:c25d:dd:dd:dd:cc45
712c19:dd:c25:c25d:dd:dd:dd:cc46/1282c19:dd:c25:c25d:dd:dd:dd:cc46
722c19:dd:c25:c25d:dd:dd:dd:cc47/1282c19:dd:c25:c25d:dd:dd:dd:cc47
732c19:dd:c25:c25d:dd:dd:dd:cc48/1282c19:dd:c25:c25d:dd:dd:dd:cc48
742c19:dd:c25:c25d:dd:dd:dd:cc49/1282c19:dd:c25:c25d:dd:dd:dd:cc49
752c19:dd:c25:c25d:dd:dd:dd:cc4a/1282c19:dd:c25:c25d:dd:dd:dd:cc4a
762c19:dd:c25:c25d:dd:dd:dd:cc4b/1282c19:dd:c25:c25d:dd:dd:dd:cc4b
772c19:dd:c25:c25d:dd:dd:dd:cc4c/1282c19:dd:c25:c25d:dd:dd:dd:cc4c
782c19:dd:c25:c25d:dd:dd:dd:cc4d/1282c19:dd:c25:c25d:dd:dd:dd:cc4d
792c19:dd:c25:c25d:dd:dd:dd:cc4e/1282c19:dd:c25:c25d:dd:dd:dd:cc4e
802c19:dd:c25:c25d:dd:dd:dd:cc4f/1282c19:dd:c25:c25d:dd:dd:dd:cc4f
812c19:dd:c25:c25d:dd:dd:dd:cc50/1282c19:dd:c25:c25d:dd:dd:dd:cc50
822c19:dd:c25:c25d:dd:dd:dd:cc51/1282c19:dd:c25:c25d:dd:dd:dd:cc51
832c19:dd:c25:c25d:dd:dd:dd:cc52/1282c19:dd:c25:c25d:dd:dd:dd:cc52
842c19:dd:c25:c25d:dd:dd:dd:cc53/1282c19:dd:c25:c25d:dd:dd:dd:cc53
852c19:dd:c25:c25d:dd:dd:dd:cc54/1282c19:dd:c25:c25d:dd:dd:dd:cc54
862c19:dd:c25:c25d:dd:dd:dd:cc55/1282c19:dd:c25:c25d:dd:dd:dd:cc55
872c19:dd:c25:c25d:dd:dd:dd:cc56/1282c19:dd:c25:c25d:dd:dd:dd:cc56
882c19:dd:c25:c25d:dd:dd:dd:cc57/1282c19:dd:c25:c25d:dd:dd:dd:cc57
892c19:dd:c25:c25d:dd:dd:dd:cc58/1282c19:dd:c25:c25d:dd:dd:dd:cc58
902c19:dd:c25:c25d:dd:dd:dd:cc59/1282c19:dd:c25:c25d:dd:dd:dd:cc59
912c19:dd:c25:c25d:dd:dd:dd:cc5a/1282c19:dd:c25:c25d:dd:dd:dd:cc5a
922c19:dd:c25:c25d:dd:dd:dd:cc5b/1282c19:dd:c25:c25d:dd:dd:dd:cc5b
932c19:dd:c25:c25d:dd:dd:dd:cc5c/1282c19:dd:c25:c25d:dd:dd:dd:cc5c
942c19:dd:c25:c25d:dd:dd:dd:cc5d/1282c19:dd:c25:c25d:dd:dd:dd:cc5d
952c19:dd:c25:c25d:dd:dd:dd:cc5e/1282c19:dd:c25:c25d:dd:dd:dd:cc5e
962c19:dd:c25:c25d:dd:dd:dd:cc5f/1282c19:dd:c25:c25d:dd:dd:dd:cc5f
972c19:dd:c25:c25d:dd:dd:dd:cc60/1282c19:dd:c25:c25d:dd:dd:dd:cc60
982c19:dd:c25:c25d:dd:dd:dd:cc61/1282c19:dd:c25:c25d:dd:dd:dd:cc61
992c19:dd:c25:c25d:dd:dd:dd:cc62/1282c19:dd:c25:c25d:dd:dd:dd:cc62
1002c19:dd:c25:c25d:dd:dd:dd:cc63/1282c19:dd:c25:c25d:dd:dd:dd:cc63
1012c19:dd:c25:c25d:dd:dd:dd:cc64/1282c19:dd:c25:c25d:dd:dd:dd:cc64
1022c19:dd:c25:c25d:dd:dd:dd:cc65/1282c19:dd:c25:c25d:dd:dd:dd:cc65
1032c19:dd:c25:c25d:dd:dd:dd:cc66/1282c19:dd:c25:c25d:dd:dd:dd:cc66
1042c19:dd:c25:c25d:dd:dd:dd:cc67/1282c19:dd:c25:c25d:dd:dd:dd:cc67
1052c19:dd:c25:c25d:dd:dd:dd:cc68/1282c19:dd:c25:c25d:dd:dd:dd:cc68
1062c19:dd:c25:c25d:dd:dd:dd:cc69/1282c19:dd:c25:c25d:dd:dd:dd:cc69
1072c19:dd:c25:c25d:dd:dd:dd:cc6a/1282c19:dd:c25:c25d:dd:dd:dd:cc6a
1082c19:dd:c25:c25d:dd:dd:dd:cc6b/1282c19:dd:c25:c25d:dd:dd:dd:cc6b
1092c19:dd:c25:c25d:dd:dd:dd:cc6c/1282c19:dd:c25:c25d:dd:dd:dd:cc6c
1102c19:dd:c25:c25d:dd:dd:dd:cc6d/1282c19:dd:c25:c25d:dd:dd:dd:cc6d
1112c19:dd:c25:c25d:dd:dd:dd:cc6e/1282c19:dd:c25:c25d:dd:dd:dd:cc6e
1122c19:dd:c25:c25d:dd:dd:dd:cc6f/1282c19:dd:c25:c25d:dd:dd:dd:cc6f
1132c19:dd:c25:c25d:dd:dd:dd:cc70/1282c19:dd:c25:c25d:dd:dd:dd:cc70
1142c19:dd:c25:c25d:dd:dd:dd:cc71/1282c19:dd:c25:c25d:dd:dd:dd:cc71
1152c19:dd:c25:c25d:dd:dd:dd:cc72/1282c19:dd:c25:c25d:dd:dd:dd:cc72
1162c19:dd:c25:c25d:dd:dd:dd:cc73/1282c19:dd:c25:c25d:dd:dd:dd:cc73
1172c19:dd:c25:c25d:dd:dd:dd:cc74/1282c19:dd:c25:c25d:dd:dd:dd:cc74
1182c19:dd:c25:c25d:dd:dd:dd:cc75/1282c19:dd:c25:c25d:dd:dd:dd:cc75
1192c19:dd:c25:c25d:dd:dd:dd:cc76/1282c19:dd:c25:c25d:dd:dd:dd:cc76
1202c19:dd:c25:c25d:dd:dd:dd:cc77/1282c19:dd:c25:c25d:dd:dd:dd:cc77
1212c19:dd:c25:c25d:dd:dd:dd:cc78/1282c19:dd:c25:c25d:dd:dd:dd:cc78
1222c19:dd:c25:c25d:dd:dd:dd:cc79/1282c19:dd:c25:c25d:dd:dd:dd:cc79
1232c19:dd:c25:c25d:dd:dd:dd:cc7a/1282c19:dd:c25:c25d:dd:dd:dd:cc7a
1242c19:dd:c25:c25d:dd:dd:dd:cc7b/1282c19:dd:c25:c25d:dd:dd:dd:cc7b
1252c19:dd:c25:c25d:dd:dd:dd:cc7c/1282c19:dd:c25:c25d:dd:dd:dd:cc7c
1262c19:dd:c25:c25d:dd:dd:dd:cc7d/1282c19:dd:c25:c25d:dd:dd:dd:cc7d
1272c19:dd:c25:c25d:dd:dd:dd:cc7e/1282c19:dd:c25:c25d:dd:dd:dd:cc7e
1282c19:dd:c25:c25d:dd:dd:dd:cc7f/1282c19:dd:c25:c25d:dd:dd:dd:cc7f
1292c19:dd:c25:c25d:dd:dd:dd:cc80/1282c19:dd:c25:c25d:dd:dd:dd:cc80
1302c19:dd:c25:c25d:dd:dd:dd:cc81/1282c19:dd:c25:c25d:dd:dd:dd:cc81
1312c19:dd:c25:c25d:dd:dd:dd:cc82/1282c19:dd:c25:c25d:dd:dd:dd:cc82
1322c19:dd:c25:c25d:dd:dd:dd:cc83/1282c19:dd:c25:c25d:dd:dd:dd:cc83
1332c19:dd:c25:c25d:dd:dd:dd:cc84/1282c19:dd:c25:c25d:dd:dd:dd:cc84
1342c19:dd:c25:c25d:dd:dd:dd:cc85/1282c19:dd:c25:c25d:dd:dd:dd:cc85
1352c19:dd:c25:c25d:dd:dd:dd:cc86/1282c19:dd:c25:c25d:dd:dd:dd:cc86
1362c19:dd:c25:c25d:dd:dd:dd:cc87/1282c19:dd:c25:c25d:dd:dd:dd:cc87
1372c19:dd:c25:c25d:dd:dd:dd:cc88/1282c19:dd:c25:c25d:dd:dd:dd:cc88
1382c19:dd:c25:c25d:dd:dd:dd:cc89/1282c19:dd:c25:c25d:dd:dd:dd:cc89
1392c19:dd:c25:c25d:dd:dd:dd:cc8a/1282c19:dd:c25:c25d:dd:dd:dd:cc8a
1402c19:dd:c25:c25d:dd:dd:dd:cc8b/1282c19:dd:c25:c25d:dd:dd:dd:cc8b
1412c19:dd:c25:c25d:dd:dd:dd:cc8c/1282c19:dd:c25:c25d:dd:dd:dd:cc8c
1422c19:dd:c25:c25d:dd:dd:dd:cc8d/1282c19:dd:c25:c25d:dd:dd:dd:cc8d
1432c19:dd:c25:c25d:dd:dd:dd:cc8e/1282c19:dd:c25:c25d:dd:dd:dd:cc8e
1442c19:dd:c25:c25d:dd:dd:dd:cc8f/1282c19:dd:c25:c25d:dd:dd:dd:cc8f
1452c19:dd:c25:c25d:dd:dd:dd:cc90/1282c19:dd:c25:c25d:dd:dd:dd:cc90
1462c19:dd:c25:c25d:dd:dd:dd:cc91/1282c19:dd:c25:c25d:dd:dd:dd:cc91
1472c19:dd:c25:c25d:dd:dd:dd:cc92/1282c19:dd:c25:c25d:dd:dd:dd:cc92
1482c19:dd:c25:c25d:dd:dd:dd:cc93/1282c19:dd:c25:c25d:dd:dd:dd:cc93
1492c19:dd:c25:c25d:dd:dd:dd:cc94/1282c19:dd:c25:c25d:dd:dd:dd:cc94
1502c19:dd:c25:c25d:dd:dd:dd:cc95/1282c19:dd:c25:c25d:dd:dd:dd:cc95
1512c19:dd:c25:c25d:dd:dd:dd:cc96/1282c19:dd:c25:c25d:dd:dd:dd:cc96
1522c19:dd:c25:c25d:dd:dd:dd:cc97/1282c19:dd:c25:c25d:dd:dd:dd:cc97
1532c19:dd:c25:c25d:dd:dd:dd:cc98/1282c19:dd:c25:c25d:dd:dd:dd:cc98
1542c19:dd:c25:c25d:dd:dd:dd:cc99/1282c19:dd:c25:c25d:dd:dd:dd:cc99
1552c19:dd:c25:c25d:dd:dd:dd:cc9a/1282c19:dd:c25:c25d:dd:dd:dd:cc9a
1562c19:dd:c25:c25d:dd:dd:dd:cc9b/1282c19:dd:c25:c25d:dd:dd:dd:cc9b
1572c19:dd:c25:c25d:dd:dd:dd:cc9c/1282c19:dd:c25:c25d:dd:dd:dd:cc9c
1582c19:dd:c25:c25d:dd:dd:dd:cc9d/1282c19:dd:c25:c25d:dd:dd:dd:cc9d
1592c19:dd:c25:c25d:dd:dd:dd:cc9e/1282c19:dd:c25:c25d:dd:dd:dd:cc9e
1602c19:dd:c25:c25d:dd:dd:dd:cc9f/1282c19:dd:c25:c25d:dd:dd:dd:cc9f
1612c19:dd:c25:c25d:dd:dd:dd:cca0/1282c19:dd:c25:c25d:dd:dd:dd:cca0
1622c19:dd:c25:c25d:dd:dd:dd:cca1/1282c19:dd:c25:c25d:dd:dd:dd:cca1
1632c19:dd:c25:c25d:dd:dd:dd:cca2/1282c19:dd:c25:c25d:dd:dd:dd:cca2
1642c19:dd:c25:c25d:dd:dd:dd:cca3/1282c19:dd:c25:c25d:dd:dd:dd:cca3
1652c19:dd:c25:c25d:dd:dd:dd:cca4/1282c19:dd:c25:c25d:dd:dd:dd:cca4
1662c19:dd:c25:c25d:dd:dd:dd:cca5/1282c19:dd:c25:c25d:dd:dd:dd:cca5
1672c19:dd:c25:c25d:dd:dd:dd:cca6/1282c19:dd:c25:c25d:dd:dd:dd:cca6
1682c19:dd:c25:c25d:dd:dd:dd:cca7/1282c19:dd:c25:c25d:dd:dd:dd:cca7
1692c19:dd:c25:c25d:dd:dd:dd:cca8/1282c19:dd:c25:c25d:dd:dd:dd:cca8
1702c19:dd:c25:c25d:dd:dd:dd:cca9/1282c19:dd:c25:c25d:dd:dd:dd:cca9
1712c19:dd:c25:c25d:dd:dd:dd:ccaa/1282c19:dd:c25:c25d:dd:dd:dd:ccaa
1722c19:dd:c25:c25d:dd:dd:dd:ccab/1282c19:dd:c25:c25d:dd:dd:dd:ccab
1732c19:dd:c25:c25d:dd:dd:dd:ccac/1282c19:dd:c25:c25d:dd:dd:dd:ccac
1742c19:dd:c25:c25d:dd:dd:dd:ccad/1282c19:dd:c25:c25d:dd:dd:dd:ccad
1752c19:dd:c25:c25d:dd:dd:dd:ccae/1282c19:dd:c25:c25d:dd:dd:dd:ccae
1762c19:dd:c25:c25d:dd:dd:dd:ccaf/1282c19:dd:c25:c25d:dd:dd:dd:ccaf
1772c19:dd:c25:c25d:dd:dd:dd:ccb0/1282c19:dd:c25:c25d:dd:dd:dd:ccb0
1782c19:dd:c25:c25d:dd:dd:dd:ccb1/1282c19:dd:c25:c25d:dd:dd:dd:ccb1
1792c19:dd:c25:c25d:dd:dd:dd:ccb2/1282c19:dd:c25:c25d:dd:dd:dd:ccb2
1802c19:dd:c25:c25d:dd:dd:dd:ccb3/1282c19:dd:c25:c25d:dd:dd:dd:ccb3
1812c19:dd:c25:c25d:dd:dd:dd:ccb4/1282c19:dd:c25:c25d:dd:dd:dd:ccb4
1822c19:dd:c25:c25d:dd:dd:dd:ccb5/1282c19:dd:c25:c25d:dd:dd:dd:ccb5
1832c19:dd:c25:c25d:dd:dd:dd:ccb6/1282c19:dd:c25:c25d:dd:dd:dd:ccb6
1842c19:dd:c25:c25d:dd:dd:dd:ccb7/1282c19:dd:c25:c25d:dd:dd:dd:ccb7
1852c19:dd:c25:c25d:dd:dd:dd:ccb8/1282c19:dd:c25:c25d:dd:dd:dd:ccb8
1862c19:dd:c25:c25d:dd:dd:dd:ccb9/1282c19:dd:c25:c25d:dd:dd:dd:ccb9
1872c19:dd:c25:c25d:dd:dd:dd:ccba/1282c19:dd:c25:c25d:dd:dd:dd:ccba
1882c19:dd:c25:c25d:dd:dd:dd:ccbb/1282c19:dd:c25:c25d:dd:dd:dd:ccbb
1892c19:dd:c25:c25d:dd:dd:dd:ccbc/1282c19:dd:c25:c25d:dd:dd:dd:ccbc
1902c19:dd:c25:c25d:dd:dd:dd:ccbd/1282c19:dd:c25:c25d:dd:dd:dd:ccbd
1912c19:dd:c25:c25d:dd:dd:dd:ccbe/1282c19:dd:c25:c25d:dd:dd:dd:ccbe
1922c19:dd:c25:c25d:dd:dd:dd:ccbf/1282c19:dd:c25:c25d:dd:dd:dd:ccbf
1932c19:dd:c25:c25d:dd:dd:dd:ccc0/1282c19:dd:c25:c25d:dd:dd:dd:ccc0
1942c19:dd:c25:c25d:dd:dd:dd:ccc1/1282c19:dd:c25:c25d:dd:dd:dd:ccc1
1952c19:dd:c25:c25d:dd:dd:dd:ccc2/1282c19:dd:c25:c25d:dd:dd:dd:ccc2
1962c19:dd:c25:c25d:dd:dd:dd:ccc3/1282c19:dd:c25:c25d:dd:dd:dd:ccc3
1972c19:dd:c25:c25d:dd:dd:dd:ccc4/1282c19:dd:c25:c25d:dd:dd:dd:ccc4
1982c19:dd:c25:c25d:dd:dd:dd:ccc5/1282c19:dd:c25:c25d:dd:dd:dd:ccc5
1992c19:dd:c25:c25d:dd:dd:dd:ccc6/1282c19:dd:c25:c25d:dd:dd:dd:ccc6
2002c19:dd:c25:c25d:dd:dd:dd:ccc7/1282c19:dd:c25:c25d:dd:dd:dd:ccc7
2012c19:dd:c25:c25d:dd:dd:dd:ccc8/1282c19:dd:c25:c25d:dd:dd:dd:ccc8
2022c19:dd:c25:c25d:dd:dd:dd:ccc9/1282c19:dd:c25:c25d:dd:dd:dd:ccc9
2032c19:dd:c25:c25d:dd:dd:dd:ccca/1282c19:dd:c25:c25d:dd:dd:dd:ccca
2042c19:dd:c25:c25d:dd:dd:dd:cccb/1282c19:dd:c25:c25d:dd:dd:dd:cccb
2052c19:dd:c25:c25d:dd:dd:dd:cccc/1282c19:dd:c25:c25d:dd:dd:dd:cccc
2062c19:dd:c25:c25d:dd:dd:dd:cccd/1282c19:dd:c25:c25d:dd:dd:dd:cccd
2072c19:dd:c25:c25d:dd:dd:dd:ccce/1282c19:dd:c25:c25d:dd:dd:dd:ccce
2082c19:dd:c25:c25d:dd:dd:dd:cccf/1282c19:dd:c25:c25d:dd:dd:dd:cccf
2092c19:dd:c25:c25d:dd:dd:dd:ccd0/1282c19:dd:c25:c25d:dd:dd:dd:ccd0
2102c19:dd:c25:c25d:dd:dd:dd:ccd1/1282c19:dd:c25:c25d:dd:dd:dd:ccd1
2112c19:dd:c25:c25d:dd:dd:dd:ccd2/1282c19:dd:c25:c25d:dd:dd:dd:ccd2
2122c19:dd:c25:c25d:dd:dd:dd:ccd3/1282c19:dd:c25:c25d:dd:dd:dd:ccd3
2132c19:dd:c25:c25d:dd:dd:dd:ccd4/1282c19:dd:c25:c25d:dd:dd:dd:ccd4
2142c19:dd:c25:c25d:dd:dd:dd:ccd5/1282c19:dd:c25:c25d:dd:dd:dd:ccd5
2152c19:dd:c25:c25d:dd:dd:dd:ccd6/1282c19:dd:c25:c25d:dd:dd:dd:ccd6
2162c19:dd:c25:c25d:dd:dd:dd:ccd7/1282c19:dd:c25:c25d:dd:dd:dd:ccd7
2172c19:dd:c25:c25d:dd:dd:dd:ccd8/1282c19:dd:c25:c25d:dd:dd:dd:ccd8
2182c19:dd:c25:c25d:dd:dd:dd:ccd9/1282c19:dd:c25:c25d:dd:dd:dd:ccd9
2192c19:dd:c25:c25d:dd:dd:dd:ccda/1282c19:dd:c25:c25d:dd:dd:dd:ccda
2202c19:dd:c25:c25d:dd:dd:dd:ccdb/1282c19:dd:c25:c25d:dd:dd:dd:ccdb
2212c19:dd:c25:c25d:dd:dd:dd:ccdc/1282c19:dd:c25:c25d:dd:dd:dd:ccdc
2222c19:dd:c25:c25d:dd:dd:dd:ccdd/1282c19:dd:c25:c25d:dd:dd:dd:ccdd
2232c19:dd:c25:c25d:dd:dd:dd:ccde/1282c19:dd:c25:c25d:dd:dd:dd:ccde
2242c19:dd:c25:c25d:dd:dd:dd:ccdf/1282c19:dd:c25:c25d:dd:dd:dd:ccdf
2252c19:dd:c25:c25d:dd:dd:dd:cce0/1282c19:dd:c25:c25d:dd:dd:dd:cce0
2262c19:dd:c25:c25d:dd:dd:dd:cce1/1282c19:dd:c25:c25d:dd:dd:dd:cce1
2272c19:dd:c25:c25d:dd:dd:dd:cce2/1282c19:dd:c25:c25d:dd:dd:dd:cce2
2282c19:dd:c25:c25d:dd:dd:dd:cce3/1282c19:dd:c25:c25d:dd:dd:dd:cce3
2292c19:dd:c25:c25d:dd:dd:dd:cce4/1282c19:dd:c25:c25d:dd:dd:dd:cce4
2302c19:dd:c25:c25d:dd:dd:dd:cce5/1282c19:dd:c25:c25d:dd:dd:dd:cce5
2312c19:dd:c25:c25d:dd:dd:dd:cce6/1282c19:dd:c25:c25d:dd:dd:dd:cce6
2322c19:dd:c25:c25d:dd:dd:dd:cce7/1282c19:dd:c25:c25d:dd:dd:dd:cce7
2332c19:dd:c25:c25d:dd:dd:dd:cce8/1282c19:dd:c25:c25d:dd:dd:dd:cce8
2342c19:dd:c25:c25d:dd:dd:dd:cce9/1282c19:dd:c25:c25d:dd:dd:dd:cce9
2352c19:dd:c25:c25d:dd:dd:dd:ccea/1282c19:dd:c25:c25d:dd:dd:dd:ccea
2362c19:dd:c25:c25d:dd:dd:dd:cceb/1282c19:dd:c25:c25d:dd:dd:dd:cceb
2372c19:dd:c25:c25d:dd:dd:dd:ccec/1282c19:dd:c25:c25d:dd:dd:dd:ccec
2382c19:dd:c25:c25d:dd:dd:dd:cced/1282c19:dd:c25:c25d:dd:dd:dd:cced
2392c19:dd:c25:c25d:dd:dd:dd:ccee/1282c19:dd:c25:c25d:dd:dd:dd:ccee
2402c19:dd:c25:c25d:dd:dd:dd:ccef/1282c19:dd:c25:c25d:dd:dd:dd:ccef
2412c19:dd:c25:c25d:dd:dd:dd:ccf0/1282c19:dd:c25:c25d:dd:dd:dd:ccf0
2422c19:dd:c25:c25d:dd:dd:dd:ccf1/1282c19:dd:c25:c25d:dd:dd:dd:ccf1
2432c19:dd:c25:c25d:dd:dd:dd:ccf2/1282c19:dd:c25:c25d:dd:dd:dd:ccf2
2442c19:dd:c25:c25d:dd:dd:dd:ccf3/1282c19:dd:c25:c25d:dd:dd:dd:ccf3
2452c19:dd:c25:c25d:dd:dd:dd:ccf4/1282c19:dd:c25:c25d:dd:dd:dd:ccf4
2462c19:dd:c25:c25d:dd:dd:dd:ccf5/1282c19:dd:c25:c25d:dd:dd:dd:ccf5
2472c19:dd:c25:c25d:dd:dd:dd:ccf6/1282c19:dd:c25:c25d:dd:dd:dd:ccf6
2482c19:dd:c25:c25d:dd:dd:dd:ccf7/1282c19:dd:c25:c25d:dd:dd:dd:ccf7
2492c19:dd:c25:c25d:dd:dd:dd:ccf8/1282c19:dd:c25:c25d:dd:dd:dd:ccf8
2502c19:dd:c25:c25d:dd:dd:dd:ccf9/1282c19:dd:c25:c25d:dd:dd:dd:ccf9
2512c19:dd:c25:c25d:dd:dd:dd:ccfa/1282c19:dd:c25:c25d:dd:dd:dd:ccfa
2522c19:dd:c25:c25d:dd:dd:dd:ccfb/1282c19:dd:c25:c25d:dd:dd:dd:ccfb
2532c19:dd:c25:c25d:dd:dd:dd:ccfc/1282c19:dd:c25:c25d:dd:dd:dd:ccfc
2542c19:dd:c25:c25d:dd:dd:dd:ccfd/1282c19:dd:c25:c25d:dd:dd:dd:ccfd
2552c19:dd:c25:c25d:dd:dd:dd:ccfe/1282c19:dd:c25:c25d:dd:dd:dd:ccfe
2562c19:dd:c25:c25d:dd:dd:dd:ccff/1282c19:dd:c25:c25d:dd:dd:dd:ccff

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.