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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:c25b:d00a:7e00/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:7e00
Last address
2c19:dd:d9:dd:c25:c25b:d00a:7eff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:7e00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.7.a.0.0.d.b.5.2.c.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:c25b:d00a:7e00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:7e00/1282c19:dd:d9:dd:c25:c25b:d00a:7e00
22c19:dd:d9:dd:c25:c25b:d00a:7e01/1282c19:dd:d9:dd:c25:c25b:d00a:7e01
32c19:dd:d9:dd:c25:c25b:d00a:7e02/1282c19:dd:d9:dd:c25:c25b:d00a:7e02
42c19:dd:d9:dd:c25:c25b:d00a:7e03/1282c19:dd:d9:dd:c25:c25b:d00a:7e03
52c19:dd:d9:dd:c25:c25b:d00a:7e04/1282c19:dd:d9:dd:c25:c25b:d00a:7e04
62c19:dd:d9:dd:c25:c25b:d00a:7e05/1282c19:dd:d9:dd:c25:c25b:d00a:7e05
72c19:dd:d9:dd:c25:c25b:d00a:7e06/1282c19:dd:d9:dd:c25:c25b:d00a:7e06
82c19:dd:d9:dd:c25:c25b:d00a:7e07/1282c19:dd:d9:dd:c25:c25b:d00a:7e07
92c19:dd:d9:dd:c25:c25b:d00a:7e08/1282c19:dd:d9:dd:c25:c25b:d00a:7e08
102c19:dd:d9:dd:c25:c25b:d00a:7e09/1282c19:dd:d9:dd:c25:c25b:d00a:7e09
112c19:dd:d9:dd:c25:c25b:d00a:7e0a/1282c19:dd:d9:dd:c25:c25b:d00a:7e0a
122c19:dd:d9:dd:c25:c25b:d00a:7e0b/1282c19:dd:d9:dd:c25:c25b:d00a:7e0b
132c19:dd:d9:dd:c25:c25b:d00a:7e0c/1282c19:dd:d9:dd:c25:c25b:d00a:7e0c
142c19:dd:d9:dd:c25:c25b:d00a:7e0d/1282c19:dd:d9:dd:c25:c25b:d00a:7e0d
152c19:dd:d9:dd:c25:c25b:d00a:7e0e/1282c19:dd:d9:dd:c25:c25b:d00a:7e0e
162c19:dd:d9:dd:c25:c25b:d00a:7e0f/1282c19:dd:d9:dd:c25:c25b:d00a:7e0f
172c19:dd:d9:dd:c25:c25b:d00a:7e10/1282c19:dd:d9:dd:c25:c25b:d00a:7e10
182c19:dd:d9:dd:c25:c25b:d00a:7e11/1282c19:dd:d9:dd:c25:c25b:d00a:7e11
192c19:dd:d9:dd:c25:c25b:d00a:7e12/1282c19:dd:d9:dd:c25:c25b:d00a:7e12
202c19:dd:d9:dd:c25:c25b:d00a:7e13/1282c19:dd:d9:dd:c25:c25b:d00a:7e13
212c19:dd:d9:dd:c25:c25b:d00a:7e14/1282c19:dd:d9:dd:c25:c25b:d00a:7e14
222c19:dd:d9:dd:c25:c25b:d00a:7e15/1282c19:dd:d9:dd:c25:c25b:d00a:7e15
232c19:dd:d9:dd:c25:c25b:d00a:7e16/1282c19:dd:d9:dd:c25:c25b:d00a:7e16
242c19:dd:d9:dd:c25:c25b:d00a:7e17/1282c19:dd:d9:dd:c25:c25b:d00a:7e17
252c19:dd:d9:dd:c25:c25b:d00a:7e18/1282c19:dd:d9:dd:c25:c25b:d00a:7e18
262c19:dd:d9:dd:c25:c25b:d00a:7e19/1282c19:dd:d9:dd:c25:c25b:d00a:7e19
272c19:dd:d9:dd:c25:c25b:d00a:7e1a/1282c19:dd:d9:dd:c25:c25b:d00a:7e1a
282c19:dd:d9:dd:c25:c25b:d00a:7e1b/1282c19:dd:d9:dd:c25:c25b:d00a:7e1b
292c19:dd:d9:dd:c25:c25b:d00a:7e1c/1282c19:dd:d9:dd:c25:c25b:d00a:7e1c
302c19:dd:d9:dd:c25:c25b:d00a:7e1d/1282c19:dd:d9:dd:c25:c25b:d00a:7e1d
312c19:dd:d9:dd:c25:c25b:d00a:7e1e/1282c19:dd:d9:dd:c25:c25b:d00a:7e1e
322c19:dd:d9:dd:c25:c25b:d00a:7e1f/1282c19:dd:d9:dd:c25:c25b:d00a:7e1f
332c19:dd:d9:dd:c25:c25b:d00a:7e20/1282c19:dd:d9:dd:c25:c25b:d00a:7e20
342c19:dd:d9:dd:c25:c25b:d00a:7e21/1282c19:dd:d9:dd:c25:c25b:d00a:7e21
352c19:dd:d9:dd:c25:c25b:d00a:7e22/1282c19:dd:d9:dd:c25:c25b:d00a:7e22
362c19:dd:d9:dd:c25:c25b:d00a:7e23/1282c19:dd:d9:dd:c25:c25b:d00a:7e23
372c19:dd:d9:dd:c25:c25b:d00a:7e24/1282c19:dd:d9:dd:c25:c25b:d00a:7e24
382c19:dd:d9:dd:c25:c25b:d00a:7e25/1282c19:dd:d9:dd:c25:c25b:d00a:7e25
392c19:dd:d9:dd:c25:c25b:d00a:7e26/1282c19:dd:d9:dd:c25:c25b:d00a:7e26
402c19:dd:d9:dd:c25:c25b:d00a:7e27/1282c19:dd:d9:dd:c25:c25b:d00a:7e27
412c19:dd:d9:dd:c25:c25b:d00a:7e28/1282c19:dd:d9:dd:c25:c25b:d00a:7e28
422c19:dd:d9:dd:c25:c25b:d00a:7e29/1282c19:dd:d9:dd:c25:c25b:d00a:7e29
432c19:dd:d9:dd:c25:c25b:d00a:7e2a/1282c19:dd:d9:dd:c25:c25b:d00a:7e2a
442c19:dd:d9:dd:c25:c25b:d00a:7e2b/1282c19:dd:d9:dd:c25:c25b:d00a:7e2b
452c19:dd:d9:dd:c25:c25b:d00a:7e2c/1282c19:dd:d9:dd:c25:c25b:d00a:7e2c
462c19:dd:d9:dd:c25:c25b:d00a:7e2d/1282c19:dd:d9:dd:c25:c25b:d00a:7e2d
472c19:dd:d9:dd:c25:c25b:d00a:7e2e/1282c19:dd:d9:dd:c25:c25b:d00a:7e2e
482c19:dd:d9:dd:c25:c25b:d00a:7e2f/1282c19:dd:d9:dd:c25:c25b:d00a:7e2f
492c19:dd:d9:dd:c25:c25b:d00a:7e30/1282c19:dd:d9:dd:c25:c25b:d00a:7e30
502c19:dd:d9:dd:c25:c25b:d00a:7e31/1282c19:dd:d9:dd:c25:c25b:d00a:7e31
512c19:dd:d9:dd:c25:c25b:d00a:7e32/1282c19:dd:d9:dd:c25:c25b:d00a:7e32
522c19:dd:d9:dd:c25:c25b:d00a:7e33/1282c19:dd:d9:dd:c25:c25b:d00a:7e33
532c19:dd:d9:dd:c25:c25b:d00a:7e34/1282c19:dd:d9:dd:c25:c25b:d00a:7e34
542c19:dd:d9:dd:c25:c25b:d00a:7e35/1282c19:dd:d9:dd:c25:c25b:d00a:7e35
552c19:dd:d9:dd:c25:c25b:d00a:7e36/1282c19:dd:d9:dd:c25:c25b:d00a:7e36
562c19:dd:d9:dd:c25:c25b:d00a:7e37/1282c19:dd:d9:dd:c25:c25b:d00a:7e37
572c19:dd:d9:dd:c25:c25b:d00a:7e38/1282c19:dd:d9:dd:c25:c25b:d00a:7e38
582c19:dd:d9:dd:c25:c25b:d00a:7e39/1282c19:dd:d9:dd:c25:c25b:d00a:7e39
592c19:dd:d9:dd:c25:c25b:d00a:7e3a/1282c19:dd:d9:dd:c25:c25b:d00a:7e3a
602c19:dd:d9:dd:c25:c25b:d00a:7e3b/1282c19:dd:d9:dd:c25:c25b:d00a:7e3b
612c19:dd:d9:dd:c25:c25b:d00a:7e3c/1282c19:dd:d9:dd:c25:c25b:d00a:7e3c
622c19:dd:d9:dd:c25:c25b:d00a:7e3d/1282c19:dd:d9:dd:c25:c25b:d00a:7e3d
632c19:dd:d9:dd:c25:c25b:d00a:7e3e/1282c19:dd:d9:dd:c25:c25b:d00a:7e3e
642c19:dd:d9:dd:c25:c25b:d00a:7e3f/1282c19:dd:d9:dd:c25:c25b:d00a:7e3f
652c19:dd:d9:dd:c25:c25b:d00a:7e40/1282c19:dd:d9:dd:c25:c25b:d00a:7e40
662c19:dd:d9:dd:c25:c25b:d00a:7e41/1282c19:dd:d9:dd:c25:c25b:d00a:7e41
672c19:dd:d9:dd:c25:c25b:d00a:7e42/1282c19:dd:d9:dd:c25:c25b:d00a:7e42
682c19:dd:d9:dd:c25:c25b:d00a:7e43/1282c19:dd:d9:dd:c25:c25b:d00a:7e43
692c19:dd:d9:dd:c25:c25b:d00a:7e44/1282c19:dd:d9:dd:c25:c25b:d00a:7e44
702c19:dd:d9:dd:c25:c25b:d00a:7e45/1282c19:dd:d9:dd:c25:c25b:d00a:7e45
712c19:dd:d9:dd:c25:c25b:d00a:7e46/1282c19:dd:d9:dd:c25:c25b:d00a:7e46
722c19:dd:d9:dd:c25:c25b:d00a:7e47/1282c19:dd:d9:dd:c25:c25b:d00a:7e47
732c19:dd:d9:dd:c25:c25b:d00a:7e48/1282c19:dd:d9:dd:c25:c25b:d00a:7e48
742c19:dd:d9:dd:c25:c25b:d00a:7e49/1282c19:dd:d9:dd:c25:c25b:d00a:7e49
752c19:dd:d9:dd:c25:c25b:d00a:7e4a/1282c19:dd:d9:dd:c25:c25b:d00a:7e4a
762c19:dd:d9:dd:c25:c25b:d00a:7e4b/1282c19:dd:d9:dd:c25:c25b:d00a:7e4b
772c19:dd:d9:dd:c25:c25b:d00a:7e4c/1282c19:dd:d9:dd:c25:c25b:d00a:7e4c
782c19:dd:d9:dd:c25:c25b:d00a:7e4d/1282c19:dd:d9:dd:c25:c25b:d00a:7e4d
792c19:dd:d9:dd:c25:c25b:d00a:7e4e/1282c19:dd:d9:dd:c25:c25b:d00a:7e4e
802c19:dd:d9:dd:c25:c25b:d00a:7e4f/1282c19:dd:d9:dd:c25:c25b:d00a:7e4f
812c19:dd:d9:dd:c25:c25b:d00a:7e50/1282c19:dd:d9:dd:c25:c25b:d00a:7e50
822c19:dd:d9:dd:c25:c25b:d00a:7e51/1282c19:dd:d9:dd:c25:c25b:d00a:7e51
832c19:dd:d9:dd:c25:c25b:d00a:7e52/1282c19:dd:d9:dd:c25:c25b:d00a:7e52
842c19:dd:d9:dd:c25:c25b:d00a:7e53/1282c19:dd:d9:dd:c25:c25b:d00a:7e53
852c19:dd:d9:dd:c25:c25b:d00a:7e54/1282c19:dd:d9:dd:c25:c25b:d00a:7e54
862c19:dd:d9:dd:c25:c25b:d00a:7e55/1282c19:dd:d9:dd:c25:c25b:d00a:7e55
872c19:dd:d9:dd:c25:c25b:d00a:7e56/1282c19:dd:d9:dd:c25:c25b:d00a:7e56
882c19:dd:d9:dd:c25:c25b:d00a:7e57/1282c19:dd:d9:dd:c25:c25b:d00a:7e57
892c19:dd:d9:dd:c25:c25b:d00a:7e58/1282c19:dd:d9:dd:c25:c25b:d00a:7e58
902c19:dd:d9:dd:c25:c25b:d00a:7e59/1282c19:dd:d9:dd:c25:c25b:d00a:7e59
912c19:dd:d9:dd:c25:c25b:d00a:7e5a/1282c19:dd:d9:dd:c25:c25b:d00a:7e5a
922c19:dd:d9:dd:c25:c25b:d00a:7e5b/1282c19:dd:d9:dd:c25:c25b:d00a:7e5b
932c19:dd:d9:dd:c25:c25b:d00a:7e5c/1282c19:dd:d9:dd:c25:c25b:d00a:7e5c
942c19:dd:d9:dd:c25:c25b:d00a:7e5d/1282c19:dd:d9:dd:c25:c25b:d00a:7e5d
952c19:dd:d9:dd:c25:c25b:d00a:7e5e/1282c19:dd:d9:dd:c25:c25b:d00a:7e5e
962c19:dd:d9:dd:c25:c25b:d00a:7e5f/1282c19:dd:d9:dd:c25:c25b:d00a:7e5f
972c19:dd:d9:dd:c25:c25b:d00a:7e60/1282c19:dd:d9:dd:c25:c25b:d00a:7e60
982c19:dd:d9:dd:c25:c25b:d00a:7e61/1282c19:dd:d9:dd:c25:c25b:d00a:7e61
992c19:dd:d9:dd:c25:c25b:d00a:7e62/1282c19:dd:d9:dd:c25:c25b:d00a:7e62
1002c19:dd:d9:dd:c25:c25b:d00a:7e63/1282c19:dd:d9:dd:c25:c25b:d00a:7e63
1012c19:dd:d9:dd:c25:c25b:d00a:7e64/1282c19:dd:d9:dd:c25:c25b:d00a:7e64
1022c19:dd:d9:dd:c25:c25b:d00a:7e65/1282c19:dd:d9:dd:c25:c25b:d00a:7e65
1032c19:dd:d9:dd:c25:c25b:d00a:7e66/1282c19:dd:d9:dd:c25:c25b:d00a:7e66
1042c19:dd:d9:dd:c25:c25b:d00a:7e67/1282c19:dd:d9:dd:c25:c25b:d00a:7e67
1052c19:dd:d9:dd:c25:c25b:d00a:7e68/1282c19:dd:d9:dd:c25:c25b:d00a:7e68
1062c19:dd:d9:dd:c25:c25b:d00a:7e69/1282c19:dd:d9:dd:c25:c25b:d00a:7e69
1072c19:dd:d9:dd:c25:c25b:d00a:7e6a/1282c19:dd:d9:dd:c25:c25b:d00a:7e6a
1082c19:dd:d9:dd:c25:c25b:d00a:7e6b/1282c19:dd:d9:dd:c25:c25b:d00a:7e6b
1092c19:dd:d9:dd:c25:c25b:d00a:7e6c/1282c19:dd:d9:dd:c25:c25b:d00a:7e6c
1102c19:dd:d9:dd:c25:c25b:d00a:7e6d/1282c19:dd:d9:dd:c25:c25b:d00a:7e6d
1112c19:dd:d9:dd:c25:c25b:d00a:7e6e/1282c19:dd:d9:dd:c25:c25b:d00a:7e6e
1122c19:dd:d9:dd:c25:c25b:d00a:7e6f/1282c19:dd:d9:dd:c25:c25b:d00a:7e6f
1132c19:dd:d9:dd:c25:c25b:d00a:7e70/1282c19:dd:d9:dd:c25:c25b:d00a:7e70
1142c19:dd:d9:dd:c25:c25b:d00a:7e71/1282c19:dd:d9:dd:c25:c25b:d00a:7e71
1152c19:dd:d9:dd:c25:c25b:d00a:7e72/1282c19:dd:d9:dd:c25:c25b:d00a:7e72
1162c19:dd:d9:dd:c25:c25b:d00a:7e73/1282c19:dd:d9:dd:c25:c25b:d00a:7e73
1172c19:dd:d9:dd:c25:c25b:d00a:7e74/1282c19:dd:d9:dd:c25:c25b:d00a:7e74
1182c19:dd:d9:dd:c25:c25b:d00a:7e75/1282c19:dd:d9:dd:c25:c25b:d00a:7e75
1192c19:dd:d9:dd:c25:c25b:d00a:7e76/1282c19:dd:d9:dd:c25:c25b:d00a:7e76
1202c19:dd:d9:dd:c25:c25b:d00a:7e77/1282c19:dd:d9:dd:c25:c25b:d00a:7e77
1212c19:dd:d9:dd:c25:c25b:d00a:7e78/1282c19:dd:d9:dd:c25:c25b:d00a:7e78
1222c19:dd:d9:dd:c25:c25b:d00a:7e79/1282c19:dd:d9:dd:c25:c25b:d00a:7e79
1232c19:dd:d9:dd:c25:c25b:d00a:7e7a/1282c19:dd:d9:dd:c25:c25b:d00a:7e7a
1242c19:dd:d9:dd:c25:c25b:d00a:7e7b/1282c19:dd:d9:dd:c25:c25b:d00a:7e7b
1252c19:dd:d9:dd:c25:c25b:d00a:7e7c/1282c19:dd:d9:dd:c25:c25b:d00a:7e7c
1262c19:dd:d9:dd:c25:c25b:d00a:7e7d/1282c19:dd:d9:dd:c25:c25b:d00a:7e7d
1272c19:dd:d9:dd:c25:c25b:d00a:7e7e/1282c19:dd:d9:dd:c25:c25b:d00a:7e7e
1282c19:dd:d9:dd:c25:c25b:d00a:7e7f/1282c19:dd:d9:dd:c25:c25b:d00a:7e7f
1292c19:dd:d9:dd:c25:c25b:d00a:7e80/1282c19:dd:d9:dd:c25:c25b:d00a:7e80
1302c19:dd:d9:dd:c25:c25b:d00a:7e81/1282c19:dd:d9:dd:c25:c25b:d00a:7e81
1312c19:dd:d9:dd:c25:c25b:d00a:7e82/1282c19:dd:d9:dd:c25:c25b:d00a:7e82
1322c19:dd:d9:dd:c25:c25b:d00a:7e83/1282c19:dd:d9:dd:c25:c25b:d00a:7e83
1332c19:dd:d9:dd:c25:c25b:d00a:7e84/1282c19:dd:d9:dd:c25:c25b:d00a:7e84
1342c19:dd:d9:dd:c25:c25b:d00a:7e85/1282c19:dd:d9:dd:c25:c25b:d00a:7e85
1352c19:dd:d9:dd:c25:c25b:d00a:7e86/1282c19:dd:d9:dd:c25:c25b:d00a:7e86
1362c19:dd:d9:dd:c25:c25b:d00a:7e87/1282c19:dd:d9:dd:c25:c25b:d00a:7e87
1372c19:dd:d9:dd:c25:c25b:d00a:7e88/1282c19:dd:d9:dd:c25:c25b:d00a:7e88
1382c19:dd:d9:dd:c25:c25b:d00a:7e89/1282c19:dd:d9:dd:c25:c25b:d00a:7e89
1392c19:dd:d9:dd:c25:c25b:d00a:7e8a/1282c19:dd:d9:dd:c25:c25b:d00a:7e8a
1402c19:dd:d9:dd:c25:c25b:d00a:7e8b/1282c19:dd:d9:dd:c25:c25b:d00a:7e8b
1412c19:dd:d9:dd:c25:c25b:d00a:7e8c/1282c19:dd:d9:dd:c25:c25b:d00a:7e8c
1422c19:dd:d9:dd:c25:c25b:d00a:7e8d/1282c19:dd:d9:dd:c25:c25b:d00a:7e8d
1432c19:dd:d9:dd:c25:c25b:d00a:7e8e/1282c19:dd:d9:dd:c25:c25b:d00a:7e8e
1442c19:dd:d9:dd:c25:c25b:d00a:7e8f/1282c19:dd:d9:dd:c25:c25b:d00a:7e8f
1452c19:dd:d9:dd:c25:c25b:d00a:7e90/1282c19:dd:d9:dd:c25:c25b:d00a:7e90
1462c19:dd:d9:dd:c25:c25b:d00a:7e91/1282c19:dd:d9:dd:c25:c25b:d00a:7e91
1472c19:dd:d9:dd:c25:c25b:d00a:7e92/1282c19:dd:d9:dd:c25:c25b:d00a:7e92
1482c19:dd:d9:dd:c25:c25b:d00a:7e93/1282c19:dd:d9:dd:c25:c25b:d00a:7e93
1492c19:dd:d9:dd:c25:c25b:d00a:7e94/1282c19:dd:d9:dd:c25:c25b:d00a:7e94
1502c19:dd:d9:dd:c25:c25b:d00a:7e95/1282c19:dd:d9:dd:c25:c25b:d00a:7e95
1512c19:dd:d9:dd:c25:c25b:d00a:7e96/1282c19:dd:d9:dd:c25:c25b:d00a:7e96
1522c19:dd:d9:dd:c25:c25b:d00a:7e97/1282c19:dd:d9:dd:c25:c25b:d00a:7e97
1532c19:dd:d9:dd:c25:c25b:d00a:7e98/1282c19:dd:d9:dd:c25:c25b:d00a:7e98
1542c19:dd:d9:dd:c25:c25b:d00a:7e99/1282c19:dd:d9:dd:c25:c25b:d00a:7e99
1552c19:dd:d9:dd:c25:c25b:d00a:7e9a/1282c19:dd:d9:dd:c25:c25b:d00a:7e9a
1562c19:dd:d9:dd:c25:c25b:d00a:7e9b/1282c19:dd:d9:dd:c25:c25b:d00a:7e9b
1572c19:dd:d9:dd:c25:c25b:d00a:7e9c/1282c19:dd:d9:dd:c25:c25b:d00a:7e9c
1582c19:dd:d9:dd:c25:c25b:d00a:7e9d/1282c19:dd:d9:dd:c25:c25b:d00a:7e9d
1592c19:dd:d9:dd:c25:c25b:d00a:7e9e/1282c19:dd:d9:dd:c25:c25b:d00a:7e9e
1602c19:dd:d9:dd:c25:c25b:d00a:7e9f/1282c19:dd:d9:dd:c25:c25b:d00a:7e9f
1612c19:dd:d9:dd:c25:c25b:d00a:7ea0/1282c19:dd:d9:dd:c25:c25b:d00a:7ea0
1622c19:dd:d9:dd:c25:c25b:d00a:7ea1/1282c19:dd:d9:dd:c25:c25b:d00a:7ea1
1632c19:dd:d9:dd:c25:c25b:d00a:7ea2/1282c19:dd:d9:dd:c25:c25b:d00a:7ea2
1642c19:dd:d9:dd:c25:c25b:d00a:7ea3/1282c19:dd:d9:dd:c25:c25b:d00a:7ea3
1652c19:dd:d9:dd:c25:c25b:d00a:7ea4/1282c19:dd:d9:dd:c25:c25b:d00a:7ea4
1662c19:dd:d9:dd:c25:c25b:d00a:7ea5/1282c19:dd:d9:dd:c25:c25b:d00a:7ea5
1672c19:dd:d9:dd:c25:c25b:d00a:7ea6/1282c19:dd:d9:dd:c25:c25b:d00a:7ea6
1682c19:dd:d9:dd:c25:c25b:d00a:7ea7/1282c19:dd:d9:dd:c25:c25b:d00a:7ea7
1692c19:dd:d9:dd:c25:c25b:d00a:7ea8/1282c19:dd:d9:dd:c25:c25b:d00a:7ea8
1702c19:dd:d9:dd:c25:c25b:d00a:7ea9/1282c19:dd:d9:dd:c25:c25b:d00a:7ea9
1712c19:dd:d9:dd:c25:c25b:d00a:7eaa/1282c19:dd:d9:dd:c25:c25b:d00a:7eaa
1722c19:dd:d9:dd:c25:c25b:d00a:7eab/1282c19:dd:d9:dd:c25:c25b:d00a:7eab
1732c19:dd:d9:dd:c25:c25b:d00a:7eac/1282c19:dd:d9:dd:c25:c25b:d00a:7eac
1742c19:dd:d9:dd:c25:c25b:d00a:7ead/1282c19:dd:d9:dd:c25:c25b:d00a:7ead
1752c19:dd:d9:dd:c25:c25b:d00a:7eae/1282c19:dd:d9:dd:c25:c25b:d00a:7eae
1762c19:dd:d9:dd:c25:c25b:d00a:7eaf/1282c19:dd:d9:dd:c25:c25b:d00a:7eaf
1772c19:dd:d9:dd:c25:c25b:d00a:7eb0/1282c19:dd:d9:dd:c25:c25b:d00a:7eb0
1782c19:dd:d9:dd:c25:c25b:d00a:7eb1/1282c19:dd:d9:dd:c25:c25b:d00a:7eb1
1792c19:dd:d9:dd:c25:c25b:d00a:7eb2/1282c19:dd:d9:dd:c25:c25b:d00a:7eb2
1802c19:dd:d9:dd:c25:c25b:d00a:7eb3/1282c19:dd:d9:dd:c25:c25b:d00a:7eb3
1812c19:dd:d9:dd:c25:c25b:d00a:7eb4/1282c19:dd:d9:dd:c25:c25b:d00a:7eb4
1822c19:dd:d9:dd:c25:c25b:d00a:7eb5/1282c19:dd:d9:dd:c25:c25b:d00a:7eb5
1832c19:dd:d9:dd:c25:c25b:d00a:7eb6/1282c19:dd:d9:dd:c25:c25b:d00a:7eb6
1842c19:dd:d9:dd:c25:c25b:d00a:7eb7/1282c19:dd:d9:dd:c25:c25b:d00a:7eb7
1852c19:dd:d9:dd:c25:c25b:d00a:7eb8/1282c19:dd:d9:dd:c25:c25b:d00a:7eb8
1862c19:dd:d9:dd:c25:c25b:d00a:7eb9/1282c19:dd:d9:dd:c25:c25b:d00a:7eb9
1872c19:dd:d9:dd:c25:c25b:d00a:7eba/1282c19:dd:d9:dd:c25:c25b:d00a:7eba
1882c19:dd:d9:dd:c25:c25b:d00a:7ebb/1282c19:dd:d9:dd:c25:c25b:d00a:7ebb
1892c19:dd:d9:dd:c25:c25b:d00a:7ebc/1282c19:dd:d9:dd:c25:c25b:d00a:7ebc
1902c19:dd:d9:dd:c25:c25b:d00a:7ebd/1282c19:dd:d9:dd:c25:c25b:d00a:7ebd
1912c19:dd:d9:dd:c25:c25b:d00a:7ebe/1282c19:dd:d9:dd:c25:c25b:d00a:7ebe
1922c19:dd:d9:dd:c25:c25b:d00a:7ebf/1282c19:dd:d9:dd:c25:c25b:d00a:7ebf
1932c19:dd:d9:dd:c25:c25b:d00a:7ec0/1282c19:dd:d9:dd:c25:c25b:d00a:7ec0
1942c19:dd:d9:dd:c25:c25b:d00a:7ec1/1282c19:dd:d9:dd:c25:c25b:d00a:7ec1
1952c19:dd:d9:dd:c25:c25b:d00a:7ec2/1282c19:dd:d9:dd:c25:c25b:d00a:7ec2
1962c19:dd:d9:dd:c25:c25b:d00a:7ec3/1282c19:dd:d9:dd:c25:c25b:d00a:7ec3
1972c19:dd:d9:dd:c25:c25b:d00a:7ec4/1282c19:dd:d9:dd:c25:c25b:d00a:7ec4
1982c19:dd:d9:dd:c25:c25b:d00a:7ec5/1282c19:dd:d9:dd:c25:c25b:d00a:7ec5
1992c19:dd:d9:dd:c25:c25b:d00a:7ec6/1282c19:dd:d9:dd:c25:c25b:d00a:7ec6
2002c19:dd:d9:dd:c25:c25b:d00a:7ec7/1282c19:dd:d9:dd:c25:c25b:d00a:7ec7
2012c19:dd:d9:dd:c25:c25b:d00a:7ec8/1282c19:dd:d9:dd:c25:c25b:d00a:7ec8
2022c19:dd:d9:dd:c25:c25b:d00a:7ec9/1282c19:dd:d9:dd:c25:c25b:d00a:7ec9
2032c19:dd:d9:dd:c25:c25b:d00a:7eca/1282c19:dd:d9:dd:c25:c25b:d00a:7eca
2042c19:dd:d9:dd:c25:c25b:d00a:7ecb/1282c19:dd:d9:dd:c25:c25b:d00a:7ecb
2052c19:dd:d9:dd:c25:c25b:d00a:7ecc/1282c19:dd:d9:dd:c25:c25b:d00a:7ecc
2062c19:dd:d9:dd:c25:c25b:d00a:7ecd/1282c19:dd:d9:dd:c25:c25b:d00a:7ecd
2072c19:dd:d9:dd:c25:c25b:d00a:7ece/1282c19:dd:d9:dd:c25:c25b:d00a:7ece
2082c19:dd:d9:dd:c25:c25b:d00a:7ecf/1282c19:dd:d9:dd:c25:c25b:d00a:7ecf
2092c19:dd:d9:dd:c25:c25b:d00a:7ed0/1282c19:dd:d9:dd:c25:c25b:d00a:7ed0
2102c19:dd:d9:dd:c25:c25b:d00a:7ed1/1282c19:dd:d9:dd:c25:c25b:d00a:7ed1
2112c19:dd:d9:dd:c25:c25b:d00a:7ed2/1282c19:dd:d9:dd:c25:c25b:d00a:7ed2
2122c19:dd:d9:dd:c25:c25b:d00a:7ed3/1282c19:dd:d9:dd:c25:c25b:d00a:7ed3
2132c19:dd:d9:dd:c25:c25b:d00a:7ed4/1282c19:dd:d9:dd:c25:c25b:d00a:7ed4
2142c19:dd:d9:dd:c25:c25b:d00a:7ed5/1282c19:dd:d9:dd:c25:c25b:d00a:7ed5
2152c19:dd:d9:dd:c25:c25b:d00a:7ed6/1282c19:dd:d9:dd:c25:c25b:d00a:7ed6
2162c19:dd:d9:dd:c25:c25b:d00a:7ed7/1282c19:dd:d9:dd:c25:c25b:d00a:7ed7
2172c19:dd:d9:dd:c25:c25b:d00a:7ed8/1282c19:dd:d9:dd:c25:c25b:d00a:7ed8
2182c19:dd:d9:dd:c25:c25b:d00a:7ed9/1282c19:dd:d9:dd:c25:c25b:d00a:7ed9
2192c19:dd:d9:dd:c25:c25b:d00a:7eda/1282c19:dd:d9:dd:c25:c25b:d00a:7eda
2202c19:dd:d9:dd:c25:c25b:d00a:7edb/1282c19:dd:d9:dd:c25:c25b:d00a:7edb
2212c19:dd:d9:dd:c25:c25b:d00a:7edc/1282c19:dd:d9:dd:c25:c25b:d00a:7edc
2222c19:dd:d9:dd:c25:c25b:d00a:7edd/1282c19:dd:d9:dd:c25:c25b:d00a:7edd
2232c19:dd:d9:dd:c25:c25b:d00a:7ede/1282c19:dd:d9:dd:c25:c25b:d00a:7ede
2242c19:dd:d9:dd:c25:c25b:d00a:7edf/1282c19:dd:d9:dd:c25:c25b:d00a:7edf
2252c19:dd:d9:dd:c25:c25b:d00a:7ee0/1282c19:dd:d9:dd:c25:c25b:d00a:7ee0
2262c19:dd:d9:dd:c25:c25b:d00a:7ee1/1282c19:dd:d9:dd:c25:c25b:d00a:7ee1
2272c19:dd:d9:dd:c25:c25b:d00a:7ee2/1282c19:dd:d9:dd:c25:c25b:d00a:7ee2
2282c19:dd:d9:dd:c25:c25b:d00a:7ee3/1282c19:dd:d9:dd:c25:c25b:d00a:7ee3
2292c19:dd:d9:dd:c25:c25b:d00a:7ee4/1282c19:dd:d9:dd:c25:c25b:d00a:7ee4
2302c19:dd:d9:dd:c25:c25b:d00a:7ee5/1282c19:dd:d9:dd:c25:c25b:d00a:7ee5
2312c19:dd:d9:dd:c25:c25b:d00a:7ee6/1282c19:dd:d9:dd:c25:c25b:d00a:7ee6
2322c19:dd:d9:dd:c25:c25b:d00a:7ee7/1282c19:dd:d9:dd:c25:c25b:d00a:7ee7
2332c19:dd:d9:dd:c25:c25b:d00a:7ee8/1282c19:dd:d9:dd:c25:c25b:d00a:7ee8
2342c19:dd:d9:dd:c25:c25b:d00a:7ee9/1282c19:dd:d9:dd:c25:c25b:d00a:7ee9
2352c19:dd:d9:dd:c25:c25b:d00a:7eea/1282c19:dd:d9:dd:c25:c25b:d00a:7eea
2362c19:dd:d9:dd:c25:c25b:d00a:7eeb/1282c19:dd:d9:dd:c25:c25b:d00a:7eeb
2372c19:dd:d9:dd:c25:c25b:d00a:7eec/1282c19:dd:d9:dd:c25:c25b:d00a:7eec
2382c19:dd:d9:dd:c25:c25b:d00a:7eed/1282c19:dd:d9:dd:c25:c25b:d00a:7eed
2392c19:dd:d9:dd:c25:c25b:d00a:7eee/1282c19:dd:d9:dd:c25:c25b:d00a:7eee
2402c19:dd:d9:dd:c25:c25b:d00a:7eef/1282c19:dd:d9:dd:c25:c25b:d00a:7eef
2412c19:dd:d9:dd:c25:c25b:d00a:7ef0/1282c19:dd:d9:dd:c25:c25b:d00a:7ef0
2422c19:dd:d9:dd:c25:c25b:d00a:7ef1/1282c19:dd:d9:dd:c25:c25b:d00a:7ef1
2432c19:dd:d9:dd:c25:c25b:d00a:7ef2/1282c19:dd:d9:dd:c25:c25b:d00a:7ef2
2442c19:dd:d9:dd:c25:c25b:d00a:7ef3/1282c19:dd:d9:dd:c25:c25b:d00a:7ef3
2452c19:dd:d9:dd:c25:c25b:d00a:7ef4/1282c19:dd:d9:dd:c25:c25b:d00a:7ef4
2462c19:dd:d9:dd:c25:c25b:d00a:7ef5/1282c19:dd:d9:dd:c25:c25b:d00a:7ef5
2472c19:dd:d9:dd:c25:c25b:d00a:7ef6/1282c19:dd:d9:dd:c25:c25b:d00a:7ef6
2482c19:dd:d9:dd:c25:c25b:d00a:7ef7/1282c19:dd:d9:dd:c25:c25b:d00a:7ef7
2492c19:dd:d9:dd:c25:c25b:d00a:7ef8/1282c19:dd:d9:dd:c25:c25b:d00a:7ef8
2502c19:dd:d9:dd:c25:c25b:d00a:7ef9/1282c19:dd:d9:dd:c25:c25b:d00a:7ef9
2512c19:dd:d9:dd:c25:c25b:d00a:7efa/1282c19:dd:d9:dd:c25:c25b:d00a:7efa
2522c19:dd:d9:dd:c25:c25b:d00a:7efb/1282c19:dd:d9:dd:c25:c25b:d00a:7efb
2532c19:dd:d9:dd:c25:c25b:d00a:7efc/1282c19:dd:d9:dd:c25:c25b:d00a:7efc
2542c19:dd:d9:dd:c25:c25b:d00a:7efd/1282c19:dd:d9:dd:c25:c25b:d00a:7efd
2552c19:dd:d9:dd:c25:c25b:d00a:7efe/1282c19:dd:d9:dd:c25:c25b:d00a:7efe
2562c19:dd:d9:dd:c25:c25b:d00a:7eff/1282c19:dd:d9:dd:c25:c25b:d00a:7eff

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.