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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:c25a:d00a:3b00/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:3b00
Last address
2c19:dd:d9:dd:c25:c25a:d00a:3bff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:3b00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
b.3.a.0.0.d.a.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:c25a:d00a:3b00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:3b00/1282c19:dd:d9:dd:c25:c25a:d00a:3b00
22c19:dd:d9:dd:c25:c25a:d00a:3b01/1282c19:dd:d9:dd:c25:c25a:d00a:3b01
32c19:dd:d9:dd:c25:c25a:d00a:3b02/1282c19:dd:d9:dd:c25:c25a:d00a:3b02
42c19:dd:d9:dd:c25:c25a:d00a:3b03/1282c19:dd:d9:dd:c25:c25a:d00a:3b03
52c19:dd:d9:dd:c25:c25a:d00a:3b04/1282c19:dd:d9:dd:c25:c25a:d00a:3b04
62c19:dd:d9:dd:c25:c25a:d00a:3b05/1282c19:dd:d9:dd:c25:c25a:d00a:3b05
72c19:dd:d9:dd:c25:c25a:d00a:3b06/1282c19:dd:d9:dd:c25:c25a:d00a:3b06
82c19:dd:d9:dd:c25:c25a:d00a:3b07/1282c19:dd:d9:dd:c25:c25a:d00a:3b07
92c19:dd:d9:dd:c25:c25a:d00a:3b08/1282c19:dd:d9:dd:c25:c25a:d00a:3b08
102c19:dd:d9:dd:c25:c25a:d00a:3b09/1282c19:dd:d9:dd:c25:c25a:d00a:3b09
112c19:dd:d9:dd:c25:c25a:d00a:3b0a/1282c19:dd:d9:dd:c25:c25a:d00a:3b0a
122c19:dd:d9:dd:c25:c25a:d00a:3b0b/1282c19:dd:d9:dd:c25:c25a:d00a:3b0b
132c19:dd:d9:dd:c25:c25a:d00a:3b0c/1282c19:dd:d9:dd:c25:c25a:d00a:3b0c
142c19:dd:d9:dd:c25:c25a:d00a:3b0d/1282c19:dd:d9:dd:c25:c25a:d00a:3b0d
152c19:dd:d9:dd:c25:c25a:d00a:3b0e/1282c19:dd:d9:dd:c25:c25a:d00a:3b0e
162c19:dd:d9:dd:c25:c25a:d00a:3b0f/1282c19:dd:d9:dd:c25:c25a:d00a:3b0f
172c19:dd:d9:dd:c25:c25a:d00a:3b10/1282c19:dd:d9:dd:c25:c25a:d00a:3b10
182c19:dd:d9:dd:c25:c25a:d00a:3b11/1282c19:dd:d9:dd:c25:c25a:d00a:3b11
192c19:dd:d9:dd:c25:c25a:d00a:3b12/1282c19:dd:d9:dd:c25:c25a:d00a:3b12
202c19:dd:d9:dd:c25:c25a:d00a:3b13/1282c19:dd:d9:dd:c25:c25a:d00a:3b13
212c19:dd:d9:dd:c25:c25a:d00a:3b14/1282c19:dd:d9:dd:c25:c25a:d00a:3b14
222c19:dd:d9:dd:c25:c25a:d00a:3b15/1282c19:dd:d9:dd:c25:c25a:d00a:3b15
232c19:dd:d9:dd:c25:c25a:d00a:3b16/1282c19:dd:d9:dd:c25:c25a:d00a:3b16
242c19:dd:d9:dd:c25:c25a:d00a:3b17/1282c19:dd:d9:dd:c25:c25a:d00a:3b17
252c19:dd:d9:dd:c25:c25a:d00a:3b18/1282c19:dd:d9:dd:c25:c25a:d00a:3b18
262c19:dd:d9:dd:c25:c25a:d00a:3b19/1282c19:dd:d9:dd:c25:c25a:d00a:3b19
272c19:dd:d9:dd:c25:c25a:d00a:3b1a/1282c19:dd:d9:dd:c25:c25a:d00a:3b1a
282c19:dd:d9:dd:c25:c25a:d00a:3b1b/1282c19:dd:d9:dd:c25:c25a:d00a:3b1b
292c19:dd:d9:dd:c25:c25a:d00a:3b1c/1282c19:dd:d9:dd:c25:c25a:d00a:3b1c
302c19:dd:d9:dd:c25:c25a:d00a:3b1d/1282c19:dd:d9:dd:c25:c25a:d00a:3b1d
312c19:dd:d9:dd:c25:c25a:d00a:3b1e/1282c19:dd:d9:dd:c25:c25a:d00a:3b1e
322c19:dd:d9:dd:c25:c25a:d00a:3b1f/1282c19:dd:d9:dd:c25:c25a:d00a:3b1f
332c19:dd:d9:dd:c25:c25a:d00a:3b20/1282c19:dd:d9:dd:c25:c25a:d00a:3b20
342c19:dd:d9:dd:c25:c25a:d00a:3b21/1282c19:dd:d9:dd:c25:c25a:d00a:3b21
352c19:dd:d9:dd:c25:c25a:d00a:3b22/1282c19:dd:d9:dd:c25:c25a:d00a:3b22
362c19:dd:d9:dd:c25:c25a:d00a:3b23/1282c19:dd:d9:dd:c25:c25a:d00a:3b23
372c19:dd:d9:dd:c25:c25a:d00a:3b24/1282c19:dd:d9:dd:c25:c25a:d00a:3b24
382c19:dd:d9:dd:c25:c25a:d00a:3b25/1282c19:dd:d9:dd:c25:c25a:d00a:3b25
392c19:dd:d9:dd:c25:c25a:d00a:3b26/1282c19:dd:d9:dd:c25:c25a:d00a:3b26
402c19:dd:d9:dd:c25:c25a:d00a:3b27/1282c19:dd:d9:dd:c25:c25a:d00a:3b27
412c19:dd:d9:dd:c25:c25a:d00a:3b28/1282c19:dd:d9:dd:c25:c25a:d00a:3b28
422c19:dd:d9:dd:c25:c25a:d00a:3b29/1282c19:dd:d9:dd:c25:c25a:d00a:3b29
432c19:dd:d9:dd:c25:c25a:d00a:3b2a/1282c19:dd:d9:dd:c25:c25a:d00a:3b2a
442c19:dd:d9:dd:c25:c25a:d00a:3b2b/1282c19:dd:d9:dd:c25:c25a:d00a:3b2b
452c19:dd:d9:dd:c25:c25a:d00a:3b2c/1282c19:dd:d9:dd:c25:c25a:d00a:3b2c
462c19:dd:d9:dd:c25:c25a:d00a:3b2d/1282c19:dd:d9:dd:c25:c25a:d00a:3b2d
472c19:dd:d9:dd:c25:c25a:d00a:3b2e/1282c19:dd:d9:dd:c25:c25a:d00a:3b2e
482c19:dd:d9:dd:c25:c25a:d00a:3b2f/1282c19:dd:d9:dd:c25:c25a:d00a:3b2f
492c19:dd:d9:dd:c25:c25a:d00a:3b30/1282c19:dd:d9:dd:c25:c25a:d00a:3b30
502c19:dd:d9:dd:c25:c25a:d00a:3b31/1282c19:dd:d9:dd:c25:c25a:d00a:3b31
512c19:dd:d9:dd:c25:c25a:d00a:3b32/1282c19:dd:d9:dd:c25:c25a:d00a:3b32
522c19:dd:d9:dd:c25:c25a:d00a:3b33/1282c19:dd:d9:dd:c25:c25a:d00a:3b33
532c19:dd:d9:dd:c25:c25a:d00a:3b34/1282c19:dd:d9:dd:c25:c25a:d00a:3b34
542c19:dd:d9:dd:c25:c25a:d00a:3b35/1282c19:dd:d9:dd:c25:c25a:d00a:3b35
552c19:dd:d9:dd:c25:c25a:d00a:3b36/1282c19:dd:d9:dd:c25:c25a:d00a:3b36
562c19:dd:d9:dd:c25:c25a:d00a:3b37/1282c19:dd:d9:dd:c25:c25a:d00a:3b37
572c19:dd:d9:dd:c25:c25a:d00a:3b38/1282c19:dd:d9:dd:c25:c25a:d00a:3b38
582c19:dd:d9:dd:c25:c25a:d00a:3b39/1282c19:dd:d9:dd:c25:c25a:d00a:3b39
592c19:dd:d9:dd:c25:c25a:d00a:3b3a/1282c19:dd:d9:dd:c25:c25a:d00a:3b3a
602c19:dd:d9:dd:c25:c25a:d00a:3b3b/1282c19:dd:d9:dd:c25:c25a:d00a:3b3b
612c19:dd:d9:dd:c25:c25a:d00a:3b3c/1282c19:dd:d9:dd:c25:c25a:d00a:3b3c
622c19:dd:d9:dd:c25:c25a:d00a:3b3d/1282c19:dd:d9:dd:c25:c25a:d00a:3b3d
632c19:dd:d9:dd:c25:c25a:d00a:3b3e/1282c19:dd:d9:dd:c25:c25a:d00a:3b3e
642c19:dd:d9:dd:c25:c25a:d00a:3b3f/1282c19:dd:d9:dd:c25:c25a:d00a:3b3f
652c19:dd:d9:dd:c25:c25a:d00a:3b40/1282c19:dd:d9:dd:c25:c25a:d00a:3b40
662c19:dd:d9:dd:c25:c25a:d00a:3b41/1282c19:dd:d9:dd:c25:c25a:d00a:3b41
672c19:dd:d9:dd:c25:c25a:d00a:3b42/1282c19:dd:d9:dd:c25:c25a:d00a:3b42
682c19:dd:d9:dd:c25:c25a:d00a:3b43/1282c19:dd:d9:dd:c25:c25a:d00a:3b43
692c19:dd:d9:dd:c25:c25a:d00a:3b44/1282c19:dd:d9:dd:c25:c25a:d00a:3b44
702c19:dd:d9:dd:c25:c25a:d00a:3b45/1282c19:dd:d9:dd:c25:c25a:d00a:3b45
712c19:dd:d9:dd:c25:c25a:d00a:3b46/1282c19:dd:d9:dd:c25:c25a:d00a:3b46
722c19:dd:d9:dd:c25:c25a:d00a:3b47/1282c19:dd:d9:dd:c25:c25a:d00a:3b47
732c19:dd:d9:dd:c25:c25a:d00a:3b48/1282c19:dd:d9:dd:c25:c25a:d00a:3b48
742c19:dd:d9:dd:c25:c25a:d00a:3b49/1282c19:dd:d9:dd:c25:c25a:d00a:3b49
752c19:dd:d9:dd:c25:c25a:d00a:3b4a/1282c19:dd:d9:dd:c25:c25a:d00a:3b4a
762c19:dd:d9:dd:c25:c25a:d00a:3b4b/1282c19:dd:d9:dd:c25:c25a:d00a:3b4b
772c19:dd:d9:dd:c25:c25a:d00a:3b4c/1282c19:dd:d9:dd:c25:c25a:d00a:3b4c
782c19:dd:d9:dd:c25:c25a:d00a:3b4d/1282c19:dd:d9:dd:c25:c25a:d00a:3b4d
792c19:dd:d9:dd:c25:c25a:d00a:3b4e/1282c19:dd:d9:dd:c25:c25a:d00a:3b4e
802c19:dd:d9:dd:c25:c25a:d00a:3b4f/1282c19:dd:d9:dd:c25:c25a:d00a:3b4f
812c19:dd:d9:dd:c25:c25a:d00a:3b50/1282c19:dd:d9:dd:c25:c25a:d00a:3b50
822c19:dd:d9:dd:c25:c25a:d00a:3b51/1282c19:dd:d9:dd:c25:c25a:d00a:3b51
832c19:dd:d9:dd:c25:c25a:d00a:3b52/1282c19:dd:d9:dd:c25:c25a:d00a:3b52
842c19:dd:d9:dd:c25:c25a:d00a:3b53/1282c19:dd:d9:dd:c25:c25a:d00a:3b53
852c19:dd:d9:dd:c25:c25a:d00a:3b54/1282c19:dd:d9:dd:c25:c25a:d00a:3b54
862c19:dd:d9:dd:c25:c25a:d00a:3b55/1282c19:dd:d9:dd:c25:c25a:d00a:3b55
872c19:dd:d9:dd:c25:c25a:d00a:3b56/1282c19:dd:d9:dd:c25:c25a:d00a:3b56
882c19:dd:d9:dd:c25:c25a:d00a:3b57/1282c19:dd:d9:dd:c25:c25a:d00a:3b57
892c19:dd:d9:dd:c25:c25a:d00a:3b58/1282c19:dd:d9:dd:c25:c25a:d00a:3b58
902c19:dd:d9:dd:c25:c25a:d00a:3b59/1282c19:dd:d9:dd:c25:c25a:d00a:3b59
912c19:dd:d9:dd:c25:c25a:d00a:3b5a/1282c19:dd:d9:dd:c25:c25a:d00a:3b5a
922c19:dd:d9:dd:c25:c25a:d00a:3b5b/1282c19:dd:d9:dd:c25:c25a:d00a:3b5b
932c19:dd:d9:dd:c25:c25a:d00a:3b5c/1282c19:dd:d9:dd:c25:c25a:d00a:3b5c
942c19:dd:d9:dd:c25:c25a:d00a:3b5d/1282c19:dd:d9:dd:c25:c25a:d00a:3b5d
952c19:dd:d9:dd:c25:c25a:d00a:3b5e/1282c19:dd:d9:dd:c25:c25a:d00a:3b5e
962c19:dd:d9:dd:c25:c25a:d00a:3b5f/1282c19:dd:d9:dd:c25:c25a:d00a:3b5f
972c19:dd:d9:dd:c25:c25a:d00a:3b60/1282c19:dd:d9:dd:c25:c25a:d00a:3b60
982c19:dd:d9:dd:c25:c25a:d00a:3b61/1282c19:dd:d9:dd:c25:c25a:d00a:3b61
992c19:dd:d9:dd:c25:c25a:d00a:3b62/1282c19:dd:d9:dd:c25:c25a:d00a:3b62
1002c19:dd:d9:dd:c25:c25a:d00a:3b63/1282c19:dd:d9:dd:c25:c25a:d00a:3b63
1012c19:dd:d9:dd:c25:c25a:d00a:3b64/1282c19:dd:d9:dd:c25:c25a:d00a:3b64
1022c19:dd:d9:dd:c25:c25a:d00a:3b65/1282c19:dd:d9:dd:c25:c25a:d00a:3b65
1032c19:dd:d9:dd:c25:c25a:d00a:3b66/1282c19:dd:d9:dd:c25:c25a:d00a:3b66
1042c19:dd:d9:dd:c25:c25a:d00a:3b67/1282c19:dd:d9:dd:c25:c25a:d00a:3b67
1052c19:dd:d9:dd:c25:c25a:d00a:3b68/1282c19:dd:d9:dd:c25:c25a:d00a:3b68
1062c19:dd:d9:dd:c25:c25a:d00a:3b69/1282c19:dd:d9:dd:c25:c25a:d00a:3b69
1072c19:dd:d9:dd:c25:c25a:d00a:3b6a/1282c19:dd:d9:dd:c25:c25a:d00a:3b6a
1082c19:dd:d9:dd:c25:c25a:d00a:3b6b/1282c19:dd:d9:dd:c25:c25a:d00a:3b6b
1092c19:dd:d9:dd:c25:c25a:d00a:3b6c/1282c19:dd:d9:dd:c25:c25a:d00a:3b6c
1102c19:dd:d9:dd:c25:c25a:d00a:3b6d/1282c19:dd:d9:dd:c25:c25a:d00a:3b6d
1112c19:dd:d9:dd:c25:c25a:d00a:3b6e/1282c19:dd:d9:dd:c25:c25a:d00a:3b6e
1122c19:dd:d9:dd:c25:c25a:d00a:3b6f/1282c19:dd:d9:dd:c25:c25a:d00a:3b6f
1132c19:dd:d9:dd:c25:c25a:d00a:3b70/1282c19:dd:d9:dd:c25:c25a:d00a:3b70
1142c19:dd:d9:dd:c25:c25a:d00a:3b71/1282c19:dd:d9:dd:c25:c25a:d00a:3b71
1152c19:dd:d9:dd:c25:c25a:d00a:3b72/1282c19:dd:d9:dd:c25:c25a:d00a:3b72
1162c19:dd:d9:dd:c25:c25a:d00a:3b73/1282c19:dd:d9:dd:c25:c25a:d00a:3b73
1172c19:dd:d9:dd:c25:c25a:d00a:3b74/1282c19:dd:d9:dd:c25:c25a:d00a:3b74
1182c19:dd:d9:dd:c25:c25a:d00a:3b75/1282c19:dd:d9:dd:c25:c25a:d00a:3b75
1192c19:dd:d9:dd:c25:c25a:d00a:3b76/1282c19:dd:d9:dd:c25:c25a:d00a:3b76
1202c19:dd:d9:dd:c25:c25a:d00a:3b77/1282c19:dd:d9:dd:c25:c25a:d00a:3b77
1212c19:dd:d9:dd:c25:c25a:d00a:3b78/1282c19:dd:d9:dd:c25:c25a:d00a:3b78
1222c19:dd:d9:dd:c25:c25a:d00a:3b79/1282c19:dd:d9:dd:c25:c25a:d00a:3b79
1232c19:dd:d9:dd:c25:c25a:d00a:3b7a/1282c19:dd:d9:dd:c25:c25a:d00a:3b7a
1242c19:dd:d9:dd:c25:c25a:d00a:3b7b/1282c19:dd:d9:dd:c25:c25a:d00a:3b7b
1252c19:dd:d9:dd:c25:c25a:d00a:3b7c/1282c19:dd:d9:dd:c25:c25a:d00a:3b7c
1262c19:dd:d9:dd:c25:c25a:d00a:3b7d/1282c19:dd:d9:dd:c25:c25a:d00a:3b7d
1272c19:dd:d9:dd:c25:c25a:d00a:3b7e/1282c19:dd:d9:dd:c25:c25a:d00a:3b7e
1282c19:dd:d9:dd:c25:c25a:d00a:3b7f/1282c19:dd:d9:dd:c25:c25a:d00a:3b7f
1292c19:dd:d9:dd:c25:c25a:d00a:3b80/1282c19:dd:d9:dd:c25:c25a:d00a:3b80
1302c19:dd:d9:dd:c25:c25a:d00a:3b81/1282c19:dd:d9:dd:c25:c25a:d00a:3b81
1312c19:dd:d9:dd:c25:c25a:d00a:3b82/1282c19:dd:d9:dd:c25:c25a:d00a:3b82
1322c19:dd:d9:dd:c25:c25a:d00a:3b83/1282c19:dd:d9:dd:c25:c25a:d00a:3b83
1332c19:dd:d9:dd:c25:c25a:d00a:3b84/1282c19:dd:d9:dd:c25:c25a:d00a:3b84
1342c19:dd:d9:dd:c25:c25a:d00a:3b85/1282c19:dd:d9:dd:c25:c25a:d00a:3b85
1352c19:dd:d9:dd:c25:c25a:d00a:3b86/1282c19:dd:d9:dd:c25:c25a:d00a:3b86
1362c19:dd:d9:dd:c25:c25a:d00a:3b87/1282c19:dd:d9:dd:c25:c25a:d00a:3b87
1372c19:dd:d9:dd:c25:c25a:d00a:3b88/1282c19:dd:d9:dd:c25:c25a:d00a:3b88
1382c19:dd:d9:dd:c25:c25a:d00a:3b89/1282c19:dd:d9:dd:c25:c25a:d00a:3b89
1392c19:dd:d9:dd:c25:c25a:d00a:3b8a/1282c19:dd:d9:dd:c25:c25a:d00a:3b8a
1402c19:dd:d9:dd:c25:c25a:d00a:3b8b/1282c19:dd:d9:dd:c25:c25a:d00a:3b8b
1412c19:dd:d9:dd:c25:c25a:d00a:3b8c/1282c19:dd:d9:dd:c25:c25a:d00a:3b8c
1422c19:dd:d9:dd:c25:c25a:d00a:3b8d/1282c19:dd:d9:dd:c25:c25a:d00a:3b8d
1432c19:dd:d9:dd:c25:c25a:d00a:3b8e/1282c19:dd:d9:dd:c25:c25a:d00a:3b8e
1442c19:dd:d9:dd:c25:c25a:d00a:3b8f/1282c19:dd:d9:dd:c25:c25a:d00a:3b8f
1452c19:dd:d9:dd:c25:c25a:d00a:3b90/1282c19:dd:d9:dd:c25:c25a:d00a:3b90
1462c19:dd:d9:dd:c25:c25a:d00a:3b91/1282c19:dd:d9:dd:c25:c25a:d00a:3b91
1472c19:dd:d9:dd:c25:c25a:d00a:3b92/1282c19:dd:d9:dd:c25:c25a:d00a:3b92
1482c19:dd:d9:dd:c25:c25a:d00a:3b93/1282c19:dd:d9:dd:c25:c25a:d00a:3b93
1492c19:dd:d9:dd:c25:c25a:d00a:3b94/1282c19:dd:d9:dd:c25:c25a:d00a:3b94
1502c19:dd:d9:dd:c25:c25a:d00a:3b95/1282c19:dd:d9:dd:c25:c25a:d00a:3b95
1512c19:dd:d9:dd:c25:c25a:d00a:3b96/1282c19:dd:d9:dd:c25:c25a:d00a:3b96
1522c19:dd:d9:dd:c25:c25a:d00a:3b97/1282c19:dd:d9:dd:c25:c25a:d00a:3b97
1532c19:dd:d9:dd:c25:c25a:d00a:3b98/1282c19:dd:d9:dd:c25:c25a:d00a:3b98
1542c19:dd:d9:dd:c25:c25a:d00a:3b99/1282c19:dd:d9:dd:c25:c25a:d00a:3b99
1552c19:dd:d9:dd:c25:c25a:d00a:3b9a/1282c19:dd:d9:dd:c25:c25a:d00a:3b9a
1562c19:dd:d9:dd:c25:c25a:d00a:3b9b/1282c19:dd:d9:dd:c25:c25a:d00a:3b9b
1572c19:dd:d9:dd:c25:c25a:d00a:3b9c/1282c19:dd:d9:dd:c25:c25a:d00a:3b9c
1582c19:dd:d9:dd:c25:c25a:d00a:3b9d/1282c19:dd:d9:dd:c25:c25a:d00a:3b9d
1592c19:dd:d9:dd:c25:c25a:d00a:3b9e/1282c19:dd:d9:dd:c25:c25a:d00a:3b9e
1602c19:dd:d9:dd:c25:c25a:d00a:3b9f/1282c19:dd:d9:dd:c25:c25a:d00a:3b9f
1612c19:dd:d9:dd:c25:c25a:d00a:3ba0/1282c19:dd:d9:dd:c25:c25a:d00a:3ba0
1622c19:dd:d9:dd:c25:c25a:d00a:3ba1/1282c19:dd:d9:dd:c25:c25a:d00a:3ba1
1632c19:dd:d9:dd:c25:c25a:d00a:3ba2/1282c19:dd:d9:dd:c25:c25a:d00a:3ba2
1642c19:dd:d9:dd:c25:c25a:d00a:3ba3/1282c19:dd:d9:dd:c25:c25a:d00a:3ba3
1652c19:dd:d9:dd:c25:c25a:d00a:3ba4/1282c19:dd:d9:dd:c25:c25a:d00a:3ba4
1662c19:dd:d9:dd:c25:c25a:d00a:3ba5/1282c19:dd:d9:dd:c25:c25a:d00a:3ba5
1672c19:dd:d9:dd:c25:c25a:d00a:3ba6/1282c19:dd:d9:dd:c25:c25a:d00a:3ba6
1682c19:dd:d9:dd:c25:c25a:d00a:3ba7/1282c19:dd:d9:dd:c25:c25a:d00a:3ba7
1692c19:dd:d9:dd:c25:c25a:d00a:3ba8/1282c19:dd:d9:dd:c25:c25a:d00a:3ba8
1702c19:dd:d9:dd:c25:c25a:d00a:3ba9/1282c19:dd:d9:dd:c25:c25a:d00a:3ba9
1712c19:dd:d9:dd:c25:c25a:d00a:3baa/1282c19:dd:d9:dd:c25:c25a:d00a:3baa
1722c19:dd:d9:dd:c25:c25a:d00a:3bab/1282c19:dd:d9:dd:c25:c25a:d00a:3bab
1732c19:dd:d9:dd:c25:c25a:d00a:3bac/1282c19:dd:d9:dd:c25:c25a:d00a:3bac
1742c19:dd:d9:dd:c25:c25a:d00a:3bad/1282c19:dd:d9:dd:c25:c25a:d00a:3bad
1752c19:dd:d9:dd:c25:c25a:d00a:3bae/1282c19:dd:d9:dd:c25:c25a:d00a:3bae
1762c19:dd:d9:dd:c25:c25a:d00a:3baf/1282c19:dd:d9:dd:c25:c25a:d00a:3baf
1772c19:dd:d9:dd:c25:c25a:d00a:3bb0/1282c19:dd:d9:dd:c25:c25a:d00a:3bb0
1782c19:dd:d9:dd:c25:c25a:d00a:3bb1/1282c19:dd:d9:dd:c25:c25a:d00a:3bb1
1792c19:dd:d9:dd:c25:c25a:d00a:3bb2/1282c19:dd:d9:dd:c25:c25a:d00a:3bb2
1802c19:dd:d9:dd:c25:c25a:d00a:3bb3/1282c19:dd:d9:dd:c25:c25a:d00a:3bb3
1812c19:dd:d9:dd:c25:c25a:d00a:3bb4/1282c19:dd:d9:dd:c25:c25a:d00a:3bb4
1822c19:dd:d9:dd:c25:c25a:d00a:3bb5/1282c19:dd:d9:dd:c25:c25a:d00a:3bb5
1832c19:dd:d9:dd:c25:c25a:d00a:3bb6/1282c19:dd:d9:dd:c25:c25a:d00a:3bb6
1842c19:dd:d9:dd:c25:c25a:d00a:3bb7/1282c19:dd:d9:dd:c25:c25a:d00a:3bb7
1852c19:dd:d9:dd:c25:c25a:d00a:3bb8/1282c19:dd:d9:dd:c25:c25a:d00a:3bb8
1862c19:dd:d9:dd:c25:c25a:d00a:3bb9/1282c19:dd:d9:dd:c25:c25a:d00a:3bb9
1872c19:dd:d9:dd:c25:c25a:d00a:3bba/1282c19:dd:d9:dd:c25:c25a:d00a:3bba
1882c19:dd:d9:dd:c25:c25a:d00a:3bbb/1282c19:dd:d9:dd:c25:c25a:d00a:3bbb
1892c19:dd:d9:dd:c25:c25a:d00a:3bbc/1282c19:dd:d9:dd:c25:c25a:d00a:3bbc
1902c19:dd:d9:dd:c25:c25a:d00a:3bbd/1282c19:dd:d9:dd:c25:c25a:d00a:3bbd
1912c19:dd:d9:dd:c25:c25a:d00a:3bbe/1282c19:dd:d9:dd:c25:c25a:d00a:3bbe
1922c19:dd:d9:dd:c25:c25a:d00a:3bbf/1282c19:dd:d9:dd:c25:c25a:d00a:3bbf
1932c19:dd:d9:dd:c25:c25a:d00a:3bc0/1282c19:dd:d9:dd:c25:c25a:d00a:3bc0
1942c19:dd:d9:dd:c25:c25a:d00a:3bc1/1282c19:dd:d9:dd:c25:c25a:d00a:3bc1
1952c19:dd:d9:dd:c25:c25a:d00a:3bc2/1282c19:dd:d9:dd:c25:c25a:d00a:3bc2
1962c19:dd:d9:dd:c25:c25a:d00a:3bc3/1282c19:dd:d9:dd:c25:c25a:d00a:3bc3
1972c19:dd:d9:dd:c25:c25a:d00a:3bc4/1282c19:dd:d9:dd:c25:c25a:d00a:3bc4
1982c19:dd:d9:dd:c25:c25a:d00a:3bc5/1282c19:dd:d9:dd:c25:c25a:d00a:3bc5
1992c19:dd:d9:dd:c25:c25a:d00a:3bc6/1282c19:dd:d9:dd:c25:c25a:d00a:3bc6
2002c19:dd:d9:dd:c25:c25a:d00a:3bc7/1282c19:dd:d9:dd:c25:c25a:d00a:3bc7
2012c19:dd:d9:dd:c25:c25a:d00a:3bc8/1282c19:dd:d9:dd:c25:c25a:d00a:3bc8
2022c19:dd:d9:dd:c25:c25a:d00a:3bc9/1282c19:dd:d9:dd:c25:c25a:d00a:3bc9
2032c19:dd:d9:dd:c25:c25a:d00a:3bca/1282c19:dd:d9:dd:c25:c25a:d00a:3bca
2042c19:dd:d9:dd:c25:c25a:d00a:3bcb/1282c19:dd:d9:dd:c25:c25a:d00a:3bcb
2052c19:dd:d9:dd:c25:c25a:d00a:3bcc/1282c19:dd:d9:dd:c25:c25a:d00a:3bcc
2062c19:dd:d9:dd:c25:c25a:d00a:3bcd/1282c19:dd:d9:dd:c25:c25a:d00a:3bcd
2072c19:dd:d9:dd:c25:c25a:d00a:3bce/1282c19:dd:d9:dd:c25:c25a:d00a:3bce
2082c19:dd:d9:dd:c25:c25a:d00a:3bcf/1282c19:dd:d9:dd:c25:c25a:d00a:3bcf
2092c19:dd:d9:dd:c25:c25a:d00a:3bd0/1282c19:dd:d9:dd:c25:c25a:d00a:3bd0
2102c19:dd:d9:dd:c25:c25a:d00a:3bd1/1282c19:dd:d9:dd:c25:c25a:d00a:3bd1
2112c19:dd:d9:dd:c25:c25a:d00a:3bd2/1282c19:dd:d9:dd:c25:c25a:d00a:3bd2
2122c19:dd:d9:dd:c25:c25a:d00a:3bd3/1282c19:dd:d9:dd:c25:c25a:d00a:3bd3
2132c19:dd:d9:dd:c25:c25a:d00a:3bd4/1282c19:dd:d9:dd:c25:c25a:d00a:3bd4
2142c19:dd:d9:dd:c25:c25a:d00a:3bd5/1282c19:dd:d9:dd:c25:c25a:d00a:3bd5
2152c19:dd:d9:dd:c25:c25a:d00a:3bd6/1282c19:dd:d9:dd:c25:c25a:d00a:3bd6
2162c19:dd:d9:dd:c25:c25a:d00a:3bd7/1282c19:dd:d9:dd:c25:c25a:d00a:3bd7
2172c19:dd:d9:dd:c25:c25a:d00a:3bd8/1282c19:dd:d9:dd:c25:c25a:d00a:3bd8
2182c19:dd:d9:dd:c25:c25a:d00a:3bd9/1282c19:dd:d9:dd:c25:c25a:d00a:3bd9
2192c19:dd:d9:dd:c25:c25a:d00a:3bda/1282c19:dd:d9:dd:c25:c25a:d00a:3bda
2202c19:dd:d9:dd:c25:c25a:d00a:3bdb/1282c19:dd:d9:dd:c25:c25a:d00a:3bdb
2212c19:dd:d9:dd:c25:c25a:d00a:3bdc/1282c19:dd:d9:dd:c25:c25a:d00a:3bdc
2222c19:dd:d9:dd:c25:c25a:d00a:3bdd/1282c19:dd:d9:dd:c25:c25a:d00a:3bdd
2232c19:dd:d9:dd:c25:c25a:d00a:3bde/1282c19:dd:d9:dd:c25:c25a:d00a:3bde
2242c19:dd:d9:dd:c25:c25a:d00a:3bdf/1282c19:dd:d9:dd:c25:c25a:d00a:3bdf
2252c19:dd:d9:dd:c25:c25a:d00a:3be0/1282c19:dd:d9:dd:c25:c25a:d00a:3be0
2262c19:dd:d9:dd:c25:c25a:d00a:3be1/1282c19:dd:d9:dd:c25:c25a:d00a:3be1
2272c19:dd:d9:dd:c25:c25a:d00a:3be2/1282c19:dd:d9:dd:c25:c25a:d00a:3be2
2282c19:dd:d9:dd:c25:c25a:d00a:3be3/1282c19:dd:d9:dd:c25:c25a:d00a:3be3
2292c19:dd:d9:dd:c25:c25a:d00a:3be4/1282c19:dd:d9:dd:c25:c25a:d00a:3be4
2302c19:dd:d9:dd:c25:c25a:d00a:3be5/1282c19:dd:d9:dd:c25:c25a:d00a:3be5
2312c19:dd:d9:dd:c25:c25a:d00a:3be6/1282c19:dd:d9:dd:c25:c25a:d00a:3be6
2322c19:dd:d9:dd:c25:c25a:d00a:3be7/1282c19:dd:d9:dd:c25:c25a:d00a:3be7
2332c19:dd:d9:dd:c25:c25a:d00a:3be8/1282c19:dd:d9:dd:c25:c25a:d00a:3be8
2342c19:dd:d9:dd:c25:c25a:d00a:3be9/1282c19:dd:d9:dd:c25:c25a:d00a:3be9
2352c19:dd:d9:dd:c25:c25a:d00a:3bea/1282c19:dd:d9:dd:c25:c25a:d00a:3bea
2362c19:dd:d9:dd:c25:c25a:d00a:3beb/1282c19:dd:d9:dd:c25:c25a:d00a:3beb
2372c19:dd:d9:dd:c25:c25a:d00a:3bec/1282c19:dd:d9:dd:c25:c25a:d00a:3bec
2382c19:dd:d9:dd:c25:c25a:d00a:3bed/1282c19:dd:d9:dd:c25:c25a:d00a:3bed
2392c19:dd:d9:dd:c25:c25a:d00a:3bee/1282c19:dd:d9:dd:c25:c25a:d00a:3bee
2402c19:dd:d9:dd:c25:c25a:d00a:3bef/1282c19:dd:d9:dd:c25:c25a:d00a:3bef
2412c19:dd:d9:dd:c25:c25a:d00a:3bf0/1282c19:dd:d9:dd:c25:c25a:d00a:3bf0
2422c19:dd:d9:dd:c25:c25a:d00a:3bf1/1282c19:dd:d9:dd:c25:c25a:d00a:3bf1
2432c19:dd:d9:dd:c25:c25a:d00a:3bf2/1282c19:dd:d9:dd:c25:c25a:d00a:3bf2
2442c19:dd:d9:dd:c25:c25a:d00a:3bf3/1282c19:dd:d9:dd:c25:c25a:d00a:3bf3
2452c19:dd:d9:dd:c25:c25a:d00a:3bf4/1282c19:dd:d9:dd:c25:c25a:d00a:3bf4
2462c19:dd:d9:dd:c25:c25a:d00a:3bf5/1282c19:dd:d9:dd:c25:c25a:d00a:3bf5
2472c19:dd:d9:dd:c25:c25a:d00a:3bf6/1282c19:dd:d9:dd:c25:c25a:d00a:3bf6
2482c19:dd:d9:dd:c25:c25a:d00a:3bf7/1282c19:dd:d9:dd:c25:c25a:d00a:3bf7
2492c19:dd:d9:dd:c25:c25a:d00a:3bf8/1282c19:dd:d9:dd:c25:c25a:d00a:3bf8
2502c19:dd:d9:dd:c25:c25a:d00a:3bf9/1282c19:dd:d9:dd:c25:c25a:d00a:3bf9
2512c19:dd:d9:dd:c25:c25a:d00a:3bfa/1282c19:dd:d9:dd:c25:c25a:d00a:3bfa
2522c19:dd:d9:dd:c25:c25a:d00a:3bfb/1282c19:dd:d9:dd:c25:c25a:d00a:3bfb
2532c19:dd:d9:dd:c25:c25a:d00a:3bfc/1282c19:dd:d9:dd:c25:c25a:d00a:3bfc
2542c19:dd:d9:dd:c25:c25a:d00a:3bfd/1282c19:dd:d9:dd:c25:c25a:d00a:3bfd
2552c19:dd:d9:dd:c25:c25a:d00a:3bfe/1282c19:dd:d9:dd:c25:c25a:d00a:3bfe
2562c19:dd:d9:dd:c25:c25a:d00a:3bff/1282c19:dd:d9:dd:c25:c25a:d00a:3bff

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.