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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Prefix/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:b00/120
First address
2c19:dd:d9:dd:c25:c25:94de:b00
Last address
2c19:dd:d9:dd:c25:c25:94de:bff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:0b00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
b.0.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:94de:b00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:b00/1282c19:dd:d9:dd:c25:c25:94de:b00
22c19:dd:d9:dd:c25:c25:94de:b01/1282c19:dd:d9:dd:c25:c25:94de:b01
32c19:dd:d9:dd:c25:c25:94de:b02/1282c19:dd:d9:dd:c25:c25:94de:b02
42c19:dd:d9:dd:c25:c25:94de:b03/1282c19:dd:d9:dd:c25:c25:94de:b03
52c19:dd:d9:dd:c25:c25:94de:b04/1282c19:dd:d9:dd:c25:c25:94de:b04
62c19:dd:d9:dd:c25:c25:94de:b05/1282c19:dd:d9:dd:c25:c25:94de:b05
72c19:dd:d9:dd:c25:c25:94de:b06/1282c19:dd:d9:dd:c25:c25:94de:b06
82c19:dd:d9:dd:c25:c25:94de:b07/1282c19:dd:d9:dd:c25:c25:94de:b07
92c19:dd:d9:dd:c25:c25:94de:b08/1282c19:dd:d9:dd:c25:c25:94de:b08
102c19:dd:d9:dd:c25:c25:94de:b09/1282c19:dd:d9:dd:c25:c25:94de:b09
112c19:dd:d9:dd:c25:c25:94de:b0a/1282c19:dd:d9:dd:c25:c25:94de:b0a
122c19:dd:d9:dd:c25:c25:94de:b0b/1282c19:dd:d9:dd:c25:c25:94de:b0b
132c19:dd:d9:dd:c25:c25:94de:b0c/1282c19:dd:d9:dd:c25:c25:94de:b0c
142c19:dd:d9:dd:c25:c25:94de:b0d/1282c19:dd:d9:dd:c25:c25:94de:b0d
152c19:dd:d9:dd:c25:c25:94de:b0e/1282c19:dd:d9:dd:c25:c25:94de:b0e
162c19:dd:d9:dd:c25:c25:94de:b0f/1282c19:dd:d9:dd:c25:c25:94de:b0f
172c19:dd:d9:dd:c25:c25:94de:b10/1282c19:dd:d9:dd:c25:c25:94de:b10
182c19:dd:d9:dd:c25:c25:94de:b11/1282c19:dd:d9:dd:c25:c25:94de:b11
192c19:dd:d9:dd:c25:c25:94de:b12/1282c19:dd:d9:dd:c25:c25:94de:b12
202c19:dd:d9:dd:c25:c25:94de:b13/1282c19:dd:d9:dd:c25:c25:94de:b13
212c19:dd:d9:dd:c25:c25:94de:b14/1282c19:dd:d9:dd:c25:c25:94de:b14
222c19:dd:d9:dd:c25:c25:94de:b15/1282c19:dd:d9:dd:c25:c25:94de:b15
232c19:dd:d9:dd:c25:c25:94de:b16/1282c19:dd:d9:dd:c25:c25:94de:b16
242c19:dd:d9:dd:c25:c25:94de:b17/1282c19:dd:d9:dd:c25:c25:94de:b17
252c19:dd:d9:dd:c25:c25:94de:b18/1282c19:dd:d9:dd:c25:c25:94de:b18
262c19:dd:d9:dd:c25:c25:94de:b19/1282c19:dd:d9:dd:c25:c25:94de:b19
272c19:dd:d9:dd:c25:c25:94de:b1a/1282c19:dd:d9:dd:c25:c25:94de:b1a
282c19:dd:d9:dd:c25:c25:94de:b1b/1282c19:dd:d9:dd:c25:c25:94de:b1b
292c19:dd:d9:dd:c25:c25:94de:b1c/1282c19:dd:d9:dd:c25:c25:94de:b1c
302c19:dd:d9:dd:c25:c25:94de:b1d/1282c19:dd:d9:dd:c25:c25:94de:b1d
312c19:dd:d9:dd:c25:c25:94de:b1e/1282c19:dd:d9:dd:c25:c25:94de:b1e
322c19:dd:d9:dd:c25:c25:94de:b1f/1282c19:dd:d9:dd:c25:c25:94de:b1f
332c19:dd:d9:dd:c25:c25:94de:b20/1282c19:dd:d9:dd:c25:c25:94de:b20
342c19:dd:d9:dd:c25:c25:94de:b21/1282c19:dd:d9:dd:c25:c25:94de:b21
352c19:dd:d9:dd:c25:c25:94de:b22/1282c19:dd:d9:dd:c25:c25:94de:b22
362c19:dd:d9:dd:c25:c25:94de:b23/1282c19:dd:d9:dd:c25:c25:94de:b23
372c19:dd:d9:dd:c25:c25:94de:b24/1282c19:dd:d9:dd:c25:c25:94de:b24
382c19:dd:d9:dd:c25:c25:94de:b25/1282c19:dd:d9:dd:c25:c25:94de:b25
392c19:dd:d9:dd:c25:c25:94de:b26/1282c19:dd:d9:dd:c25:c25:94de:b26
402c19:dd:d9:dd:c25:c25:94de:b27/1282c19:dd:d9:dd:c25:c25:94de:b27
412c19:dd:d9:dd:c25:c25:94de:b28/1282c19:dd:d9:dd:c25:c25:94de:b28
422c19:dd:d9:dd:c25:c25:94de:b29/1282c19:dd:d9:dd:c25:c25:94de:b29
432c19:dd:d9:dd:c25:c25:94de:b2a/1282c19:dd:d9:dd:c25:c25:94de:b2a
442c19:dd:d9:dd:c25:c25:94de:b2b/1282c19:dd:d9:dd:c25:c25:94de:b2b
452c19:dd:d9:dd:c25:c25:94de:b2c/1282c19:dd:d9:dd:c25:c25:94de:b2c
462c19:dd:d9:dd:c25:c25:94de:b2d/1282c19:dd:d9:dd:c25:c25:94de:b2d
472c19:dd:d9:dd:c25:c25:94de:b2e/1282c19:dd:d9:dd:c25:c25:94de:b2e
482c19:dd:d9:dd:c25:c25:94de:b2f/1282c19:dd:d9:dd:c25:c25:94de:b2f
492c19:dd:d9:dd:c25:c25:94de:b30/1282c19:dd:d9:dd:c25:c25:94de:b30
502c19:dd:d9:dd:c25:c25:94de:b31/1282c19:dd:d9:dd:c25:c25:94de:b31
512c19:dd:d9:dd:c25:c25:94de:b32/1282c19:dd:d9:dd:c25:c25:94de:b32
522c19:dd:d9:dd:c25:c25:94de:b33/1282c19:dd:d9:dd:c25:c25:94de:b33
532c19:dd:d9:dd:c25:c25:94de:b34/1282c19:dd:d9:dd:c25:c25:94de:b34
542c19:dd:d9:dd:c25:c25:94de:b35/1282c19:dd:d9:dd:c25:c25:94de:b35
552c19:dd:d9:dd:c25:c25:94de:b36/1282c19:dd:d9:dd:c25:c25:94de:b36
562c19:dd:d9:dd:c25:c25:94de:b37/1282c19:dd:d9:dd:c25:c25:94de:b37
572c19:dd:d9:dd:c25:c25:94de:b38/1282c19:dd:d9:dd:c25:c25:94de:b38
582c19:dd:d9:dd:c25:c25:94de:b39/1282c19:dd:d9:dd:c25:c25:94de:b39
592c19:dd:d9:dd:c25:c25:94de:b3a/1282c19:dd:d9:dd:c25:c25:94de:b3a
602c19:dd:d9:dd:c25:c25:94de:b3b/1282c19:dd:d9:dd:c25:c25:94de:b3b
612c19:dd:d9:dd:c25:c25:94de:b3c/1282c19:dd:d9:dd:c25:c25:94de:b3c
622c19:dd:d9:dd:c25:c25:94de:b3d/1282c19:dd:d9:dd:c25:c25:94de:b3d
632c19:dd:d9:dd:c25:c25:94de:b3e/1282c19:dd:d9:dd:c25:c25:94de:b3e
642c19:dd:d9:dd:c25:c25:94de:b3f/1282c19:dd:d9:dd:c25:c25:94de:b3f
652c19:dd:d9:dd:c25:c25:94de:b40/1282c19:dd:d9:dd:c25:c25:94de:b40
662c19:dd:d9:dd:c25:c25:94de:b41/1282c19:dd:d9:dd:c25:c25:94de:b41
672c19:dd:d9:dd:c25:c25:94de:b42/1282c19:dd:d9:dd:c25:c25:94de:b42
682c19:dd:d9:dd:c25:c25:94de:b43/1282c19:dd:d9:dd:c25:c25:94de:b43
692c19:dd:d9:dd:c25:c25:94de:b44/1282c19:dd:d9:dd:c25:c25:94de:b44
702c19:dd:d9:dd:c25:c25:94de:b45/1282c19:dd:d9:dd:c25:c25:94de:b45
712c19:dd:d9:dd:c25:c25:94de:b46/1282c19:dd:d9:dd:c25:c25:94de:b46
722c19:dd:d9:dd:c25:c25:94de:b47/1282c19:dd:d9:dd:c25:c25:94de:b47
732c19:dd:d9:dd:c25:c25:94de:b48/1282c19:dd:d9:dd:c25:c25:94de:b48
742c19:dd:d9:dd:c25:c25:94de:b49/1282c19:dd:d9:dd:c25:c25:94de:b49
752c19:dd:d9:dd:c25:c25:94de:b4a/1282c19:dd:d9:dd:c25:c25:94de:b4a
762c19:dd:d9:dd:c25:c25:94de:b4b/1282c19:dd:d9:dd:c25:c25:94de:b4b
772c19:dd:d9:dd:c25:c25:94de:b4c/1282c19:dd:d9:dd:c25:c25:94de:b4c
782c19:dd:d9:dd:c25:c25:94de:b4d/1282c19:dd:d9:dd:c25:c25:94de:b4d
792c19:dd:d9:dd:c25:c25:94de:b4e/1282c19:dd:d9:dd:c25:c25:94de:b4e
802c19:dd:d9:dd:c25:c25:94de:b4f/1282c19:dd:d9:dd:c25:c25:94de:b4f
812c19:dd:d9:dd:c25:c25:94de:b50/1282c19:dd:d9:dd:c25:c25:94de:b50
822c19:dd:d9:dd:c25:c25:94de:b51/1282c19:dd:d9:dd:c25:c25:94de:b51
832c19:dd:d9:dd:c25:c25:94de:b52/1282c19:dd:d9:dd:c25:c25:94de:b52
842c19:dd:d9:dd:c25:c25:94de:b53/1282c19:dd:d9:dd:c25:c25:94de:b53
852c19:dd:d9:dd:c25:c25:94de:b54/1282c19:dd:d9:dd:c25:c25:94de:b54
862c19:dd:d9:dd:c25:c25:94de:b55/1282c19:dd:d9:dd:c25:c25:94de:b55
872c19:dd:d9:dd:c25:c25:94de:b56/1282c19:dd:d9:dd:c25:c25:94de:b56
882c19:dd:d9:dd:c25:c25:94de:b57/1282c19:dd:d9:dd:c25:c25:94de:b57
892c19:dd:d9:dd:c25:c25:94de:b58/1282c19:dd:d9:dd:c25:c25:94de:b58
902c19:dd:d9:dd:c25:c25:94de:b59/1282c19:dd:d9:dd:c25:c25:94de:b59
912c19:dd:d9:dd:c25:c25:94de:b5a/1282c19:dd:d9:dd:c25:c25:94de:b5a
922c19:dd:d9:dd:c25:c25:94de:b5b/1282c19:dd:d9:dd:c25:c25:94de:b5b
932c19:dd:d9:dd:c25:c25:94de:b5c/1282c19:dd:d9:dd:c25:c25:94de:b5c
942c19:dd:d9:dd:c25:c25:94de:b5d/1282c19:dd:d9:dd:c25:c25:94de:b5d
952c19:dd:d9:dd:c25:c25:94de:b5e/1282c19:dd:d9:dd:c25:c25:94de:b5e
962c19:dd:d9:dd:c25:c25:94de:b5f/1282c19:dd:d9:dd:c25:c25:94de:b5f
972c19:dd:d9:dd:c25:c25:94de:b60/1282c19:dd:d9:dd:c25:c25:94de:b60
982c19:dd:d9:dd:c25:c25:94de:b61/1282c19:dd:d9:dd:c25:c25:94de:b61
992c19:dd:d9:dd:c25:c25:94de:b62/1282c19:dd:d9:dd:c25:c25:94de:b62
1002c19:dd:d9:dd:c25:c25:94de:b63/1282c19:dd:d9:dd:c25:c25:94de:b63
1012c19:dd:d9:dd:c25:c25:94de:b64/1282c19:dd:d9:dd:c25:c25:94de:b64
1022c19:dd:d9:dd:c25:c25:94de:b65/1282c19:dd:d9:dd:c25:c25:94de:b65
1032c19:dd:d9:dd:c25:c25:94de:b66/1282c19:dd:d9:dd:c25:c25:94de:b66
1042c19:dd:d9:dd:c25:c25:94de:b67/1282c19:dd:d9:dd:c25:c25:94de:b67
1052c19:dd:d9:dd:c25:c25:94de:b68/1282c19:dd:d9:dd:c25:c25:94de:b68
1062c19:dd:d9:dd:c25:c25:94de:b69/1282c19:dd:d9:dd:c25:c25:94de:b69
1072c19:dd:d9:dd:c25:c25:94de:b6a/1282c19:dd:d9:dd:c25:c25:94de:b6a
1082c19:dd:d9:dd:c25:c25:94de:b6b/1282c19:dd:d9:dd:c25:c25:94de:b6b
1092c19:dd:d9:dd:c25:c25:94de:b6c/1282c19:dd:d9:dd:c25:c25:94de:b6c
1102c19:dd:d9:dd:c25:c25:94de:b6d/1282c19:dd:d9:dd:c25:c25:94de:b6d
1112c19:dd:d9:dd:c25:c25:94de:b6e/1282c19:dd:d9:dd:c25:c25:94de:b6e
1122c19:dd:d9:dd:c25:c25:94de:b6f/1282c19:dd:d9:dd:c25:c25:94de:b6f
1132c19:dd:d9:dd:c25:c25:94de:b70/1282c19:dd:d9:dd:c25:c25:94de:b70
1142c19:dd:d9:dd:c25:c25:94de:b71/1282c19:dd:d9:dd:c25:c25:94de:b71
1152c19:dd:d9:dd:c25:c25:94de:b72/1282c19:dd:d9:dd:c25:c25:94de:b72
1162c19:dd:d9:dd:c25:c25:94de:b73/1282c19:dd:d9:dd:c25:c25:94de:b73
1172c19:dd:d9:dd:c25:c25:94de:b74/1282c19:dd:d9:dd:c25:c25:94de:b74
1182c19:dd:d9:dd:c25:c25:94de:b75/1282c19:dd:d9:dd:c25:c25:94de:b75
1192c19:dd:d9:dd:c25:c25:94de:b76/1282c19:dd:d9:dd:c25:c25:94de:b76
1202c19:dd:d9:dd:c25:c25:94de:b77/1282c19:dd:d9:dd:c25:c25:94de:b77
1212c19:dd:d9:dd:c25:c25:94de:b78/1282c19:dd:d9:dd:c25:c25:94de:b78
1222c19:dd:d9:dd:c25:c25:94de:b79/1282c19:dd:d9:dd:c25:c25:94de:b79
1232c19:dd:d9:dd:c25:c25:94de:b7a/1282c19:dd:d9:dd:c25:c25:94de:b7a
1242c19:dd:d9:dd:c25:c25:94de:b7b/1282c19:dd:d9:dd:c25:c25:94de:b7b
1252c19:dd:d9:dd:c25:c25:94de:b7c/1282c19:dd:d9:dd:c25:c25:94de:b7c
1262c19:dd:d9:dd:c25:c25:94de:b7d/1282c19:dd:d9:dd:c25:c25:94de:b7d
1272c19:dd:d9:dd:c25:c25:94de:b7e/1282c19:dd:d9:dd:c25:c25:94de:b7e
1282c19:dd:d9:dd:c25:c25:94de:b7f/1282c19:dd:d9:dd:c25:c25:94de:b7f
1292c19:dd:d9:dd:c25:c25:94de:b80/1282c19:dd:d9:dd:c25:c25:94de:b80
1302c19:dd:d9:dd:c25:c25:94de:b81/1282c19:dd:d9:dd:c25:c25:94de:b81
1312c19:dd:d9:dd:c25:c25:94de:b82/1282c19:dd:d9:dd:c25:c25:94de:b82
1322c19:dd:d9:dd:c25:c25:94de:b83/1282c19:dd:d9:dd:c25:c25:94de:b83
1332c19:dd:d9:dd:c25:c25:94de:b84/1282c19:dd:d9:dd:c25:c25:94de:b84
1342c19:dd:d9:dd:c25:c25:94de:b85/1282c19:dd:d9:dd:c25:c25:94de:b85
1352c19:dd:d9:dd:c25:c25:94de:b86/1282c19:dd:d9:dd:c25:c25:94de:b86
1362c19:dd:d9:dd:c25:c25:94de:b87/1282c19:dd:d9:dd:c25:c25:94de:b87
1372c19:dd:d9:dd:c25:c25:94de:b88/1282c19:dd:d9:dd:c25:c25:94de:b88
1382c19:dd:d9:dd:c25:c25:94de:b89/1282c19:dd:d9:dd:c25:c25:94de:b89
1392c19:dd:d9:dd:c25:c25:94de:b8a/1282c19:dd:d9:dd:c25:c25:94de:b8a
1402c19:dd:d9:dd:c25:c25:94de:b8b/1282c19:dd:d9:dd:c25:c25:94de:b8b
1412c19:dd:d9:dd:c25:c25:94de:b8c/1282c19:dd:d9:dd:c25:c25:94de:b8c
1422c19:dd:d9:dd:c25:c25:94de:b8d/1282c19:dd:d9:dd:c25:c25:94de:b8d
1432c19:dd:d9:dd:c25:c25:94de:b8e/1282c19:dd:d9:dd:c25:c25:94de:b8e
1442c19:dd:d9:dd:c25:c25:94de:b8f/1282c19:dd:d9:dd:c25:c25:94de:b8f
1452c19:dd:d9:dd:c25:c25:94de:b90/1282c19:dd:d9:dd:c25:c25:94de:b90
1462c19:dd:d9:dd:c25:c25:94de:b91/1282c19:dd:d9:dd:c25:c25:94de:b91
1472c19:dd:d9:dd:c25:c25:94de:b92/1282c19:dd:d9:dd:c25:c25:94de:b92
1482c19:dd:d9:dd:c25:c25:94de:b93/1282c19:dd:d9:dd:c25:c25:94de:b93
1492c19:dd:d9:dd:c25:c25:94de:b94/1282c19:dd:d9:dd:c25:c25:94de:b94
1502c19:dd:d9:dd:c25:c25:94de:b95/1282c19:dd:d9:dd:c25:c25:94de:b95
1512c19:dd:d9:dd:c25:c25:94de:b96/1282c19:dd:d9:dd:c25:c25:94de:b96
1522c19:dd:d9:dd:c25:c25:94de:b97/1282c19:dd:d9:dd:c25:c25:94de:b97
1532c19:dd:d9:dd:c25:c25:94de:b98/1282c19:dd:d9:dd:c25:c25:94de:b98
1542c19:dd:d9:dd:c25:c25:94de:b99/1282c19:dd:d9:dd:c25:c25:94de:b99
1552c19:dd:d9:dd:c25:c25:94de:b9a/1282c19:dd:d9:dd:c25:c25:94de:b9a
1562c19:dd:d9:dd:c25:c25:94de:b9b/1282c19:dd:d9:dd:c25:c25:94de:b9b
1572c19:dd:d9:dd:c25:c25:94de:b9c/1282c19:dd:d9:dd:c25:c25:94de:b9c
1582c19:dd:d9:dd:c25:c25:94de:b9d/1282c19:dd:d9:dd:c25:c25:94de:b9d
1592c19:dd:d9:dd:c25:c25:94de:b9e/1282c19:dd:d9:dd:c25:c25:94de:b9e
1602c19:dd:d9:dd:c25:c25:94de:b9f/1282c19:dd:d9:dd:c25:c25:94de:b9f
1612c19:dd:d9:dd:c25:c25:94de:ba0/1282c19:dd:d9:dd:c25:c25:94de:ba0
1622c19:dd:d9:dd:c25:c25:94de:ba1/1282c19:dd:d9:dd:c25:c25:94de:ba1
1632c19:dd:d9:dd:c25:c25:94de:ba2/1282c19:dd:d9:dd:c25:c25:94de:ba2
1642c19:dd:d9:dd:c25:c25:94de:ba3/1282c19:dd:d9:dd:c25:c25:94de:ba3
1652c19:dd:d9:dd:c25:c25:94de:ba4/1282c19:dd:d9:dd:c25:c25:94de:ba4
1662c19:dd:d9:dd:c25:c25:94de:ba5/1282c19:dd:d9:dd:c25:c25:94de:ba5
1672c19:dd:d9:dd:c25:c25:94de:ba6/1282c19:dd:d9:dd:c25:c25:94de:ba6
1682c19:dd:d9:dd:c25:c25:94de:ba7/1282c19:dd:d9:dd:c25:c25:94de:ba7
1692c19:dd:d9:dd:c25:c25:94de:ba8/1282c19:dd:d9:dd:c25:c25:94de:ba8
1702c19:dd:d9:dd:c25:c25:94de:ba9/1282c19:dd:d9:dd:c25:c25:94de:ba9
1712c19:dd:d9:dd:c25:c25:94de:baa/1282c19:dd:d9:dd:c25:c25:94de:baa
1722c19:dd:d9:dd:c25:c25:94de:bab/1282c19:dd:d9:dd:c25:c25:94de:bab
1732c19:dd:d9:dd:c25:c25:94de:bac/1282c19:dd:d9:dd:c25:c25:94de:bac
1742c19:dd:d9:dd:c25:c25:94de:bad/1282c19:dd:d9:dd:c25:c25:94de:bad
1752c19:dd:d9:dd:c25:c25:94de:bae/1282c19:dd:d9:dd:c25:c25:94de:bae
1762c19:dd:d9:dd:c25:c25:94de:baf/1282c19:dd:d9:dd:c25:c25:94de:baf
1772c19:dd:d9:dd:c25:c25:94de:bb0/1282c19:dd:d9:dd:c25:c25:94de:bb0
1782c19:dd:d9:dd:c25:c25:94de:bb1/1282c19:dd:d9:dd:c25:c25:94de:bb1
1792c19:dd:d9:dd:c25:c25:94de:bb2/1282c19:dd:d9:dd:c25:c25:94de:bb2
1802c19:dd:d9:dd:c25:c25:94de:bb3/1282c19:dd:d9:dd:c25:c25:94de:bb3
1812c19:dd:d9:dd:c25:c25:94de:bb4/1282c19:dd:d9:dd:c25:c25:94de:bb4
1822c19:dd:d9:dd:c25:c25:94de:bb5/1282c19:dd:d9:dd:c25:c25:94de:bb5
1832c19:dd:d9:dd:c25:c25:94de:bb6/1282c19:dd:d9:dd:c25:c25:94de:bb6
1842c19:dd:d9:dd:c25:c25:94de:bb7/1282c19:dd:d9:dd:c25:c25:94de:bb7
1852c19:dd:d9:dd:c25:c25:94de:bb8/1282c19:dd:d9:dd:c25:c25:94de:bb8
1862c19:dd:d9:dd:c25:c25:94de:bb9/1282c19:dd:d9:dd:c25:c25:94de:bb9
1872c19:dd:d9:dd:c25:c25:94de:bba/1282c19:dd:d9:dd:c25:c25:94de:bba
1882c19:dd:d9:dd:c25:c25:94de:bbb/1282c19:dd:d9:dd:c25:c25:94de:bbb
1892c19:dd:d9:dd:c25:c25:94de:bbc/1282c19:dd:d9:dd:c25:c25:94de:bbc
1902c19:dd:d9:dd:c25:c25:94de:bbd/1282c19:dd:d9:dd:c25:c25:94de:bbd
1912c19:dd:d9:dd:c25:c25:94de:bbe/1282c19:dd:d9:dd:c25:c25:94de:bbe
1922c19:dd:d9:dd:c25:c25:94de:bbf/1282c19:dd:d9:dd:c25:c25:94de:bbf
1932c19:dd:d9:dd:c25:c25:94de:bc0/1282c19:dd:d9:dd:c25:c25:94de:bc0
1942c19:dd:d9:dd:c25:c25:94de:bc1/1282c19:dd:d9:dd:c25:c25:94de:bc1
1952c19:dd:d9:dd:c25:c25:94de:bc2/1282c19:dd:d9:dd:c25:c25:94de:bc2
1962c19:dd:d9:dd:c25:c25:94de:bc3/1282c19:dd:d9:dd:c25:c25:94de:bc3
1972c19:dd:d9:dd:c25:c25:94de:bc4/1282c19:dd:d9:dd:c25:c25:94de:bc4
1982c19:dd:d9:dd:c25:c25:94de:bc5/1282c19:dd:d9:dd:c25:c25:94de:bc5
1992c19:dd:d9:dd:c25:c25:94de:bc6/1282c19:dd:d9:dd:c25:c25:94de:bc6
2002c19:dd:d9:dd:c25:c25:94de:bc7/1282c19:dd:d9:dd:c25:c25:94de:bc7
2012c19:dd:d9:dd:c25:c25:94de:bc8/1282c19:dd:d9:dd:c25:c25:94de:bc8
2022c19:dd:d9:dd:c25:c25:94de:bc9/1282c19:dd:d9:dd:c25:c25:94de:bc9
2032c19:dd:d9:dd:c25:c25:94de:bca/1282c19:dd:d9:dd:c25:c25:94de:bca
2042c19:dd:d9:dd:c25:c25:94de:bcb/1282c19:dd:d9:dd:c25:c25:94de:bcb
2052c19:dd:d9:dd:c25:c25:94de:bcc/1282c19:dd:d9:dd:c25:c25:94de:bcc
2062c19:dd:d9:dd:c25:c25:94de:bcd/1282c19:dd:d9:dd:c25:c25:94de:bcd
2072c19:dd:d9:dd:c25:c25:94de:bce/1282c19:dd:d9:dd:c25:c25:94de:bce
2082c19:dd:d9:dd:c25:c25:94de:bcf/1282c19:dd:d9:dd:c25:c25:94de:bcf
2092c19:dd:d9:dd:c25:c25:94de:bd0/1282c19:dd:d9:dd:c25:c25:94de:bd0
2102c19:dd:d9:dd:c25:c25:94de:bd1/1282c19:dd:d9:dd:c25:c25:94de:bd1
2112c19:dd:d9:dd:c25:c25:94de:bd2/1282c19:dd:d9:dd:c25:c25:94de:bd2
2122c19:dd:d9:dd:c25:c25:94de:bd3/1282c19:dd:d9:dd:c25:c25:94de:bd3
2132c19:dd:d9:dd:c25:c25:94de:bd4/1282c19:dd:d9:dd:c25:c25:94de:bd4
2142c19:dd:d9:dd:c25:c25:94de:bd5/1282c19:dd:d9:dd:c25:c25:94de:bd5
2152c19:dd:d9:dd:c25:c25:94de:bd6/1282c19:dd:d9:dd:c25:c25:94de:bd6
2162c19:dd:d9:dd:c25:c25:94de:bd7/1282c19:dd:d9:dd:c25:c25:94de:bd7
2172c19:dd:d9:dd:c25:c25:94de:bd8/1282c19:dd:d9:dd:c25:c25:94de:bd8
2182c19:dd:d9:dd:c25:c25:94de:bd9/1282c19:dd:d9:dd:c25:c25:94de:bd9
2192c19:dd:d9:dd:c25:c25:94de:bda/1282c19:dd:d9:dd:c25:c25:94de:bda
2202c19:dd:d9:dd:c25:c25:94de:bdb/1282c19:dd:d9:dd:c25:c25:94de:bdb
2212c19:dd:d9:dd:c25:c25:94de:bdc/1282c19:dd:d9:dd:c25:c25:94de:bdc
2222c19:dd:d9:dd:c25:c25:94de:bdd/1282c19:dd:d9:dd:c25:c25:94de:bdd
2232c19:dd:d9:dd:c25:c25:94de:bde/1282c19:dd:d9:dd:c25:c25:94de:bde
2242c19:dd:d9:dd:c25:c25:94de:bdf/1282c19:dd:d9:dd:c25:c25:94de:bdf
2252c19:dd:d9:dd:c25:c25:94de:be0/1282c19:dd:d9:dd:c25:c25:94de:be0
2262c19:dd:d9:dd:c25:c25:94de:be1/1282c19:dd:d9:dd:c25:c25:94de:be1
2272c19:dd:d9:dd:c25:c25:94de:be2/1282c19:dd:d9:dd:c25:c25:94de:be2
2282c19:dd:d9:dd:c25:c25:94de:be3/1282c19:dd:d9:dd:c25:c25:94de:be3
2292c19:dd:d9:dd:c25:c25:94de:be4/1282c19:dd:d9:dd:c25:c25:94de:be4
2302c19:dd:d9:dd:c25:c25:94de:be5/1282c19:dd:d9:dd:c25:c25:94de:be5
2312c19:dd:d9:dd:c25:c25:94de:be6/1282c19:dd:d9:dd:c25:c25:94de:be6
2322c19:dd:d9:dd:c25:c25:94de:be7/1282c19:dd:d9:dd:c25:c25:94de:be7
2332c19:dd:d9:dd:c25:c25:94de:be8/1282c19:dd:d9:dd:c25:c25:94de:be8
2342c19:dd:d9:dd:c25:c25:94de:be9/1282c19:dd:d9:dd:c25:c25:94de:be9
2352c19:dd:d9:dd:c25:c25:94de:bea/1282c19:dd:d9:dd:c25:c25:94de:bea
2362c19:dd:d9:dd:c25:c25:94de:beb/1282c19:dd:d9:dd:c25:c25:94de:beb
2372c19:dd:d9:dd:c25:c25:94de:bec/1282c19:dd:d9:dd:c25:c25:94de:bec
2382c19:dd:d9:dd:c25:c25:94de:bed/1282c19:dd:d9:dd:c25:c25:94de:bed
2392c19:dd:d9:dd:c25:c25:94de:bee/1282c19:dd:d9:dd:c25:c25:94de:bee
2402c19:dd:d9:dd:c25:c25:94de:bef/1282c19:dd:d9:dd:c25:c25:94de:bef
2412c19:dd:d9:dd:c25:c25:94de:bf0/1282c19:dd:d9:dd:c25:c25:94de:bf0
2422c19:dd:d9:dd:c25:c25:94de:bf1/1282c19:dd:d9:dd:c25:c25:94de:bf1
2432c19:dd:d9:dd:c25:c25:94de:bf2/1282c19:dd:d9:dd:c25:c25:94de:bf2
2442c19:dd:d9:dd:c25:c25:94de:bf3/1282c19:dd:d9:dd:c25:c25:94de:bf3
2452c19:dd:d9:dd:c25:c25:94de:bf4/1282c19:dd:d9:dd:c25:c25:94de:bf4
2462c19:dd:d9:dd:c25:c25:94de:bf5/1282c19:dd:d9:dd:c25:c25:94de:bf5
2472c19:dd:d9:dd:c25:c25:94de:bf6/1282c19:dd:d9:dd:c25:c25:94de:bf6
2482c19:dd:d9:dd:c25:c25:94de:bf7/1282c19:dd:d9:dd:c25:c25:94de:bf7
2492c19:dd:d9:dd:c25:c25:94de:bf8/1282c19:dd:d9:dd:c25:c25:94de:bf8
2502c19:dd:d9:dd:c25:c25:94de:bf9/1282c19:dd:d9:dd:c25:c25:94de:bf9
2512c19:dd:d9:dd:c25:c25:94de:bfa/1282c19:dd:d9:dd:c25:c25:94de:bfa
2522c19:dd:d9:dd:c25:c25:94de:bfb/1282c19:dd:d9:dd:c25:c25:94de:bfb
2532c19:dd:d9:dd:c25:c25:94de:bfc/1282c19:dd:d9:dd:c25:c25:94de:bfc
2542c19:dd:d9:dd:c25:c25:94de:bfd/1282c19:dd:d9:dd:c25:c25:94de:bfd
2552c19:dd:d9:dd:c25:c25:94de:bfe/1282c19:dd:d9:dd:c25:c25:94de:bfe
2562c19:dd:d9:dd:c25:c25:94de:bff/1282c19:dd:d9:dd:c25:c25:94de:bff

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.