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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:3c00/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:3c00
Last address
2c19:dd:d9:dd:c25:c25a:d00a:3cff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:3c00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
c.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:3c00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:3c00/1282c19:dd:d9:dd:c25:c25a:d00a:3c00
22c19:dd:d9:dd:c25:c25a:d00a:3c01/1282c19:dd:d9:dd:c25:c25a:d00a:3c01
32c19:dd:d9:dd:c25:c25a:d00a:3c02/1282c19:dd:d9:dd:c25:c25a:d00a:3c02
42c19:dd:d9:dd:c25:c25a:d00a:3c03/1282c19:dd:d9:dd:c25:c25a:d00a:3c03
52c19:dd:d9:dd:c25:c25a:d00a:3c04/1282c19:dd:d9:dd:c25:c25a:d00a:3c04
62c19:dd:d9:dd:c25:c25a:d00a:3c05/1282c19:dd:d9:dd:c25:c25a:d00a:3c05
72c19:dd:d9:dd:c25:c25a:d00a:3c06/1282c19:dd:d9:dd:c25:c25a:d00a:3c06
82c19:dd:d9:dd:c25:c25a:d00a:3c07/1282c19:dd:d9:dd:c25:c25a:d00a:3c07
92c19:dd:d9:dd:c25:c25a:d00a:3c08/1282c19:dd:d9:dd:c25:c25a:d00a:3c08
102c19:dd:d9:dd:c25:c25a:d00a:3c09/1282c19:dd:d9:dd:c25:c25a:d00a:3c09
112c19:dd:d9:dd:c25:c25a:d00a:3c0a/1282c19:dd:d9:dd:c25:c25a:d00a:3c0a
122c19:dd:d9:dd:c25:c25a:d00a:3c0b/1282c19:dd:d9:dd:c25:c25a:d00a:3c0b
132c19:dd:d9:dd:c25:c25a:d00a:3c0c/1282c19:dd:d9:dd:c25:c25a:d00a:3c0c
142c19:dd:d9:dd:c25:c25a:d00a:3c0d/1282c19:dd:d9:dd:c25:c25a:d00a:3c0d
152c19:dd:d9:dd:c25:c25a:d00a:3c0e/1282c19:dd:d9:dd:c25:c25a:d00a:3c0e
162c19:dd:d9:dd:c25:c25a:d00a:3c0f/1282c19:dd:d9:dd:c25:c25a:d00a:3c0f
172c19:dd:d9:dd:c25:c25a:d00a:3c10/1282c19:dd:d9:dd:c25:c25a:d00a:3c10
182c19:dd:d9:dd:c25:c25a:d00a:3c11/1282c19:dd:d9:dd:c25:c25a:d00a:3c11
192c19:dd:d9:dd:c25:c25a:d00a:3c12/1282c19:dd:d9:dd:c25:c25a:d00a:3c12
202c19:dd:d9:dd:c25:c25a:d00a:3c13/1282c19:dd:d9:dd:c25:c25a:d00a:3c13
212c19:dd:d9:dd:c25:c25a:d00a:3c14/1282c19:dd:d9:dd:c25:c25a:d00a:3c14
222c19:dd:d9:dd:c25:c25a:d00a:3c15/1282c19:dd:d9:dd:c25:c25a:d00a:3c15
232c19:dd:d9:dd:c25:c25a:d00a:3c16/1282c19:dd:d9:dd:c25:c25a:d00a:3c16
242c19:dd:d9:dd:c25:c25a:d00a:3c17/1282c19:dd:d9:dd:c25:c25a:d00a:3c17
252c19:dd:d9:dd:c25:c25a:d00a:3c18/1282c19:dd:d9:dd:c25:c25a:d00a:3c18
262c19:dd:d9:dd:c25:c25a:d00a:3c19/1282c19:dd:d9:dd:c25:c25a:d00a:3c19
272c19:dd:d9:dd:c25:c25a:d00a:3c1a/1282c19:dd:d9:dd:c25:c25a:d00a:3c1a
282c19:dd:d9:dd:c25:c25a:d00a:3c1b/1282c19:dd:d9:dd:c25:c25a:d00a:3c1b
292c19:dd:d9:dd:c25:c25a:d00a:3c1c/1282c19:dd:d9:dd:c25:c25a:d00a:3c1c
302c19:dd:d9:dd:c25:c25a:d00a:3c1d/1282c19:dd:d9:dd:c25:c25a:d00a:3c1d
312c19:dd:d9:dd:c25:c25a:d00a:3c1e/1282c19:dd:d9:dd:c25:c25a:d00a:3c1e
322c19:dd:d9:dd:c25:c25a:d00a:3c1f/1282c19:dd:d9:dd:c25:c25a:d00a:3c1f
332c19:dd:d9:dd:c25:c25a:d00a:3c20/1282c19:dd:d9:dd:c25:c25a:d00a:3c20
342c19:dd:d9:dd:c25:c25a:d00a:3c21/1282c19:dd:d9:dd:c25:c25a:d00a:3c21
352c19:dd:d9:dd:c25:c25a:d00a:3c22/1282c19:dd:d9:dd:c25:c25a:d00a:3c22
362c19:dd:d9:dd:c25:c25a:d00a:3c23/1282c19:dd:d9:dd:c25:c25a:d00a:3c23
372c19:dd:d9:dd:c25:c25a:d00a:3c24/1282c19:dd:d9:dd:c25:c25a:d00a:3c24
382c19:dd:d9:dd:c25:c25a:d00a:3c25/1282c19:dd:d9:dd:c25:c25a:d00a:3c25
392c19:dd:d9:dd:c25:c25a:d00a:3c26/1282c19:dd:d9:dd:c25:c25a:d00a:3c26
402c19:dd:d9:dd:c25:c25a:d00a:3c27/1282c19:dd:d9:dd:c25:c25a:d00a:3c27
412c19:dd:d9:dd:c25:c25a:d00a:3c28/1282c19:dd:d9:dd:c25:c25a:d00a:3c28
422c19:dd:d9:dd:c25:c25a:d00a:3c29/1282c19:dd:d9:dd:c25:c25a:d00a:3c29
432c19:dd:d9:dd:c25:c25a:d00a:3c2a/1282c19:dd:d9:dd:c25:c25a:d00a:3c2a
442c19:dd:d9:dd:c25:c25a:d00a:3c2b/1282c19:dd:d9:dd:c25:c25a:d00a:3c2b
452c19:dd:d9:dd:c25:c25a:d00a:3c2c/1282c19:dd:d9:dd:c25:c25a:d00a:3c2c
462c19:dd:d9:dd:c25:c25a:d00a:3c2d/1282c19:dd:d9:dd:c25:c25a:d00a:3c2d
472c19:dd:d9:dd:c25:c25a:d00a:3c2e/1282c19:dd:d9:dd:c25:c25a:d00a:3c2e
482c19:dd:d9:dd:c25:c25a:d00a:3c2f/1282c19:dd:d9:dd:c25:c25a:d00a:3c2f
492c19:dd:d9:dd:c25:c25a:d00a:3c30/1282c19:dd:d9:dd:c25:c25a:d00a:3c30
502c19:dd:d9:dd:c25:c25a:d00a:3c31/1282c19:dd:d9:dd:c25:c25a:d00a:3c31
512c19:dd:d9:dd:c25:c25a:d00a:3c32/1282c19:dd:d9:dd:c25:c25a:d00a:3c32
522c19:dd:d9:dd:c25:c25a:d00a:3c33/1282c19:dd:d9:dd:c25:c25a:d00a:3c33
532c19:dd:d9:dd:c25:c25a:d00a:3c34/1282c19:dd:d9:dd:c25:c25a:d00a:3c34
542c19:dd:d9:dd:c25:c25a:d00a:3c35/1282c19:dd:d9:dd:c25:c25a:d00a:3c35
552c19:dd:d9:dd:c25:c25a:d00a:3c36/1282c19:dd:d9:dd:c25:c25a:d00a:3c36
562c19:dd:d9:dd:c25:c25a:d00a:3c37/1282c19:dd:d9:dd:c25:c25a:d00a:3c37
572c19:dd:d9:dd:c25:c25a:d00a:3c38/1282c19:dd:d9:dd:c25:c25a:d00a:3c38
582c19:dd:d9:dd:c25:c25a:d00a:3c39/1282c19:dd:d9:dd:c25:c25a:d00a:3c39
592c19:dd:d9:dd:c25:c25a:d00a:3c3a/1282c19:dd:d9:dd:c25:c25a:d00a:3c3a
602c19:dd:d9:dd:c25:c25a:d00a:3c3b/1282c19:dd:d9:dd:c25:c25a:d00a:3c3b
612c19:dd:d9:dd:c25:c25a:d00a:3c3c/1282c19:dd:d9:dd:c25:c25a:d00a:3c3c
622c19:dd:d9:dd:c25:c25a:d00a:3c3d/1282c19:dd:d9:dd:c25:c25a:d00a:3c3d
632c19:dd:d9:dd:c25:c25a:d00a:3c3e/1282c19:dd:d9:dd:c25:c25a:d00a:3c3e
642c19:dd:d9:dd:c25:c25a:d00a:3c3f/1282c19:dd:d9:dd:c25:c25a:d00a:3c3f
652c19:dd:d9:dd:c25:c25a:d00a:3c40/1282c19:dd:d9:dd:c25:c25a:d00a:3c40
662c19:dd:d9:dd:c25:c25a:d00a:3c41/1282c19:dd:d9:dd:c25:c25a:d00a:3c41
672c19:dd:d9:dd:c25:c25a:d00a:3c42/1282c19:dd:d9:dd:c25:c25a:d00a:3c42
682c19:dd:d9:dd:c25:c25a:d00a:3c43/1282c19:dd:d9:dd:c25:c25a:d00a:3c43
692c19:dd:d9:dd:c25:c25a:d00a:3c44/1282c19:dd:d9:dd:c25:c25a:d00a:3c44
702c19:dd:d9:dd:c25:c25a:d00a:3c45/1282c19:dd:d9:dd:c25:c25a:d00a:3c45
712c19:dd:d9:dd:c25:c25a:d00a:3c46/1282c19:dd:d9:dd:c25:c25a:d00a:3c46
722c19:dd:d9:dd:c25:c25a:d00a:3c47/1282c19:dd:d9:dd:c25:c25a:d00a:3c47
732c19:dd:d9:dd:c25:c25a:d00a:3c48/1282c19:dd:d9:dd:c25:c25a:d00a:3c48
742c19:dd:d9:dd:c25:c25a:d00a:3c49/1282c19:dd:d9:dd:c25:c25a:d00a:3c49
752c19:dd:d9:dd:c25:c25a:d00a:3c4a/1282c19:dd:d9:dd:c25:c25a:d00a:3c4a
762c19:dd:d9:dd:c25:c25a:d00a:3c4b/1282c19:dd:d9:dd:c25:c25a:d00a:3c4b
772c19:dd:d9:dd:c25:c25a:d00a:3c4c/1282c19:dd:d9:dd:c25:c25a:d00a:3c4c
782c19:dd:d9:dd:c25:c25a:d00a:3c4d/1282c19:dd:d9:dd:c25:c25a:d00a:3c4d
792c19:dd:d9:dd:c25:c25a:d00a:3c4e/1282c19:dd:d9:dd:c25:c25a:d00a:3c4e
802c19:dd:d9:dd:c25:c25a:d00a:3c4f/1282c19:dd:d9:dd:c25:c25a:d00a:3c4f
812c19:dd:d9:dd:c25:c25a:d00a:3c50/1282c19:dd:d9:dd:c25:c25a:d00a:3c50
822c19:dd:d9:dd:c25:c25a:d00a:3c51/1282c19:dd:d9:dd:c25:c25a:d00a:3c51
832c19:dd:d9:dd:c25:c25a:d00a:3c52/1282c19:dd:d9:dd:c25:c25a:d00a:3c52
842c19:dd:d9:dd:c25:c25a:d00a:3c53/1282c19:dd:d9:dd:c25:c25a:d00a:3c53
852c19:dd:d9:dd:c25:c25a:d00a:3c54/1282c19:dd:d9:dd:c25:c25a:d00a:3c54
862c19:dd:d9:dd:c25:c25a:d00a:3c55/1282c19:dd:d9:dd:c25:c25a:d00a:3c55
872c19:dd:d9:dd:c25:c25a:d00a:3c56/1282c19:dd:d9:dd:c25:c25a:d00a:3c56
882c19:dd:d9:dd:c25:c25a:d00a:3c57/1282c19:dd:d9:dd:c25:c25a:d00a:3c57
892c19:dd:d9:dd:c25:c25a:d00a:3c58/1282c19:dd:d9:dd:c25:c25a:d00a:3c58
902c19:dd:d9:dd:c25:c25a:d00a:3c59/1282c19:dd:d9:dd:c25:c25a:d00a:3c59
912c19:dd:d9:dd:c25:c25a:d00a:3c5a/1282c19:dd:d9:dd:c25:c25a:d00a:3c5a
922c19:dd:d9:dd:c25:c25a:d00a:3c5b/1282c19:dd:d9:dd:c25:c25a:d00a:3c5b
932c19:dd:d9:dd:c25:c25a:d00a:3c5c/1282c19:dd:d9:dd:c25:c25a:d00a:3c5c
942c19:dd:d9:dd:c25:c25a:d00a:3c5d/1282c19:dd:d9:dd:c25:c25a:d00a:3c5d
952c19:dd:d9:dd:c25:c25a:d00a:3c5e/1282c19:dd:d9:dd:c25:c25a:d00a:3c5e
962c19:dd:d9:dd:c25:c25a:d00a:3c5f/1282c19:dd:d9:dd:c25:c25a:d00a:3c5f
972c19:dd:d9:dd:c25:c25a:d00a:3c60/1282c19:dd:d9:dd:c25:c25a:d00a:3c60
982c19:dd:d9:dd:c25:c25a:d00a:3c61/1282c19:dd:d9:dd:c25:c25a:d00a:3c61
992c19:dd:d9:dd:c25:c25a:d00a:3c62/1282c19:dd:d9:dd:c25:c25a:d00a:3c62
1002c19:dd:d9:dd:c25:c25a:d00a:3c63/1282c19:dd:d9:dd:c25:c25a:d00a:3c63
1012c19:dd:d9:dd:c25:c25a:d00a:3c64/1282c19:dd:d9:dd:c25:c25a:d00a:3c64
1022c19:dd:d9:dd:c25:c25a:d00a:3c65/1282c19:dd:d9:dd:c25:c25a:d00a:3c65
1032c19:dd:d9:dd:c25:c25a:d00a:3c66/1282c19:dd:d9:dd:c25:c25a:d00a:3c66
1042c19:dd:d9:dd:c25:c25a:d00a:3c67/1282c19:dd:d9:dd:c25:c25a:d00a:3c67
1052c19:dd:d9:dd:c25:c25a:d00a:3c68/1282c19:dd:d9:dd:c25:c25a:d00a:3c68
1062c19:dd:d9:dd:c25:c25a:d00a:3c69/1282c19:dd:d9:dd:c25:c25a:d00a:3c69
1072c19:dd:d9:dd:c25:c25a:d00a:3c6a/1282c19:dd:d9:dd:c25:c25a:d00a:3c6a
1082c19:dd:d9:dd:c25:c25a:d00a:3c6b/1282c19:dd:d9:dd:c25:c25a:d00a:3c6b
1092c19:dd:d9:dd:c25:c25a:d00a:3c6c/1282c19:dd:d9:dd:c25:c25a:d00a:3c6c
1102c19:dd:d9:dd:c25:c25a:d00a:3c6d/1282c19:dd:d9:dd:c25:c25a:d00a:3c6d
1112c19:dd:d9:dd:c25:c25a:d00a:3c6e/1282c19:dd:d9:dd:c25:c25a:d00a:3c6e
1122c19:dd:d9:dd:c25:c25a:d00a:3c6f/1282c19:dd:d9:dd:c25:c25a:d00a:3c6f
1132c19:dd:d9:dd:c25:c25a:d00a:3c70/1282c19:dd:d9:dd:c25:c25a:d00a:3c70
1142c19:dd:d9:dd:c25:c25a:d00a:3c71/1282c19:dd:d9:dd:c25:c25a:d00a:3c71
1152c19:dd:d9:dd:c25:c25a:d00a:3c72/1282c19:dd:d9:dd:c25:c25a:d00a:3c72
1162c19:dd:d9:dd:c25:c25a:d00a:3c73/1282c19:dd:d9:dd:c25:c25a:d00a:3c73
1172c19:dd:d9:dd:c25:c25a:d00a:3c74/1282c19:dd:d9:dd:c25:c25a:d00a:3c74
1182c19:dd:d9:dd:c25:c25a:d00a:3c75/1282c19:dd:d9:dd:c25:c25a:d00a:3c75
1192c19:dd:d9:dd:c25:c25a:d00a:3c76/1282c19:dd:d9:dd:c25:c25a:d00a:3c76
1202c19:dd:d9:dd:c25:c25a:d00a:3c77/1282c19:dd:d9:dd:c25:c25a:d00a:3c77
1212c19:dd:d9:dd:c25:c25a:d00a:3c78/1282c19:dd:d9:dd:c25:c25a:d00a:3c78
1222c19:dd:d9:dd:c25:c25a:d00a:3c79/1282c19:dd:d9:dd:c25:c25a:d00a:3c79
1232c19:dd:d9:dd:c25:c25a:d00a:3c7a/1282c19:dd:d9:dd:c25:c25a:d00a:3c7a
1242c19:dd:d9:dd:c25:c25a:d00a:3c7b/1282c19:dd:d9:dd:c25:c25a:d00a:3c7b
1252c19:dd:d9:dd:c25:c25a:d00a:3c7c/1282c19:dd:d9:dd:c25:c25a:d00a:3c7c
1262c19:dd:d9:dd:c25:c25a:d00a:3c7d/1282c19:dd:d9:dd:c25:c25a:d00a:3c7d
1272c19:dd:d9:dd:c25:c25a:d00a:3c7e/1282c19:dd:d9:dd:c25:c25a:d00a:3c7e
1282c19:dd:d9:dd:c25:c25a:d00a:3c7f/1282c19:dd:d9:dd:c25:c25a:d00a:3c7f
1292c19:dd:d9:dd:c25:c25a:d00a:3c80/1282c19:dd:d9:dd:c25:c25a:d00a:3c80
1302c19:dd:d9:dd:c25:c25a:d00a:3c81/1282c19:dd:d9:dd:c25:c25a:d00a:3c81
1312c19:dd:d9:dd:c25:c25a:d00a:3c82/1282c19:dd:d9:dd:c25:c25a:d00a:3c82
1322c19:dd:d9:dd:c25:c25a:d00a:3c83/1282c19:dd:d9:dd:c25:c25a:d00a:3c83
1332c19:dd:d9:dd:c25:c25a:d00a:3c84/1282c19:dd:d9:dd:c25:c25a:d00a:3c84
1342c19:dd:d9:dd:c25:c25a:d00a:3c85/1282c19:dd:d9:dd:c25:c25a:d00a:3c85
1352c19:dd:d9:dd:c25:c25a:d00a:3c86/1282c19:dd:d9:dd:c25:c25a:d00a:3c86
1362c19:dd:d9:dd:c25:c25a:d00a:3c87/1282c19:dd:d9:dd:c25:c25a:d00a:3c87
1372c19:dd:d9:dd:c25:c25a:d00a:3c88/1282c19:dd:d9:dd:c25:c25a:d00a:3c88
1382c19:dd:d9:dd:c25:c25a:d00a:3c89/1282c19:dd:d9:dd:c25:c25a:d00a:3c89
1392c19:dd:d9:dd:c25:c25a:d00a:3c8a/1282c19:dd:d9:dd:c25:c25a:d00a:3c8a
1402c19:dd:d9:dd:c25:c25a:d00a:3c8b/1282c19:dd:d9:dd:c25:c25a:d00a:3c8b
1412c19:dd:d9:dd:c25:c25a:d00a:3c8c/1282c19:dd:d9:dd:c25:c25a:d00a:3c8c
1422c19:dd:d9:dd:c25:c25a:d00a:3c8d/1282c19:dd:d9:dd:c25:c25a:d00a:3c8d
1432c19:dd:d9:dd:c25:c25a:d00a:3c8e/1282c19:dd:d9:dd:c25:c25a:d00a:3c8e
1442c19:dd:d9:dd:c25:c25a:d00a:3c8f/1282c19:dd:d9:dd:c25:c25a:d00a:3c8f
1452c19:dd:d9:dd:c25:c25a:d00a:3c90/1282c19:dd:d9:dd:c25:c25a:d00a:3c90
1462c19:dd:d9:dd:c25:c25a:d00a:3c91/1282c19:dd:d9:dd:c25:c25a:d00a:3c91
1472c19:dd:d9:dd:c25:c25a:d00a:3c92/1282c19:dd:d9:dd:c25:c25a:d00a:3c92
1482c19:dd:d9:dd:c25:c25a:d00a:3c93/1282c19:dd:d9:dd:c25:c25a:d00a:3c93
1492c19:dd:d9:dd:c25:c25a:d00a:3c94/1282c19:dd:d9:dd:c25:c25a:d00a:3c94
1502c19:dd:d9:dd:c25:c25a:d00a:3c95/1282c19:dd:d9:dd:c25:c25a:d00a:3c95
1512c19:dd:d9:dd:c25:c25a:d00a:3c96/1282c19:dd:d9:dd:c25:c25a:d00a:3c96
1522c19:dd:d9:dd:c25:c25a:d00a:3c97/1282c19:dd:d9:dd:c25:c25a:d00a:3c97
1532c19:dd:d9:dd:c25:c25a:d00a:3c98/1282c19:dd:d9:dd:c25:c25a:d00a:3c98
1542c19:dd:d9:dd:c25:c25a:d00a:3c99/1282c19:dd:d9:dd:c25:c25a:d00a:3c99
1552c19:dd:d9:dd:c25:c25a:d00a:3c9a/1282c19:dd:d9:dd:c25:c25a:d00a:3c9a
1562c19:dd:d9:dd:c25:c25a:d00a:3c9b/1282c19:dd:d9:dd:c25:c25a:d00a:3c9b
1572c19:dd:d9:dd:c25:c25a:d00a:3c9c/1282c19:dd:d9:dd:c25:c25a:d00a:3c9c
1582c19:dd:d9:dd:c25:c25a:d00a:3c9d/1282c19:dd:d9:dd:c25:c25a:d00a:3c9d
1592c19:dd:d9:dd:c25:c25a:d00a:3c9e/1282c19:dd:d9:dd:c25:c25a:d00a:3c9e
1602c19:dd:d9:dd:c25:c25a:d00a:3c9f/1282c19:dd:d9:dd:c25:c25a:d00a:3c9f
1612c19:dd:d9:dd:c25:c25a:d00a:3ca0/1282c19:dd:d9:dd:c25:c25a:d00a:3ca0
1622c19:dd:d9:dd:c25:c25a:d00a:3ca1/1282c19:dd:d9:dd:c25:c25a:d00a:3ca1
1632c19:dd:d9:dd:c25:c25a:d00a:3ca2/1282c19:dd:d9:dd:c25:c25a:d00a:3ca2
1642c19:dd:d9:dd:c25:c25a:d00a:3ca3/1282c19:dd:d9:dd:c25:c25a:d00a:3ca3
1652c19:dd:d9:dd:c25:c25a:d00a:3ca4/1282c19:dd:d9:dd:c25:c25a:d00a:3ca4
1662c19:dd:d9:dd:c25:c25a:d00a:3ca5/1282c19:dd:d9:dd:c25:c25a:d00a:3ca5
1672c19:dd:d9:dd:c25:c25a:d00a:3ca6/1282c19:dd:d9:dd:c25:c25a:d00a:3ca6
1682c19:dd:d9:dd:c25:c25a:d00a:3ca7/1282c19:dd:d9:dd:c25:c25a:d00a:3ca7
1692c19:dd:d9:dd:c25:c25a:d00a:3ca8/1282c19:dd:d9:dd:c25:c25a:d00a:3ca8
1702c19:dd:d9:dd:c25:c25a:d00a:3ca9/1282c19:dd:d9:dd:c25:c25a:d00a:3ca9
1712c19:dd:d9:dd:c25:c25a:d00a:3caa/1282c19:dd:d9:dd:c25:c25a:d00a:3caa
1722c19:dd:d9:dd:c25:c25a:d00a:3cab/1282c19:dd:d9:dd:c25:c25a:d00a:3cab
1732c19:dd:d9:dd:c25:c25a:d00a:3cac/1282c19:dd:d9:dd:c25:c25a:d00a:3cac
1742c19:dd:d9:dd:c25:c25a:d00a:3cad/1282c19:dd:d9:dd:c25:c25a:d00a:3cad
1752c19:dd:d9:dd:c25:c25a:d00a:3cae/1282c19:dd:d9:dd:c25:c25a:d00a:3cae
1762c19:dd:d9:dd:c25:c25a:d00a:3caf/1282c19:dd:d9:dd:c25:c25a:d00a:3caf
1772c19:dd:d9:dd:c25:c25a:d00a:3cb0/1282c19:dd:d9:dd:c25:c25a:d00a:3cb0
1782c19:dd:d9:dd:c25:c25a:d00a:3cb1/1282c19:dd:d9:dd:c25:c25a:d00a:3cb1
1792c19:dd:d9:dd:c25:c25a:d00a:3cb2/1282c19:dd:d9:dd:c25:c25a:d00a:3cb2
1802c19:dd:d9:dd:c25:c25a:d00a:3cb3/1282c19:dd:d9:dd:c25:c25a:d00a:3cb3
1812c19:dd:d9:dd:c25:c25a:d00a:3cb4/1282c19:dd:d9:dd:c25:c25a:d00a:3cb4
1822c19:dd:d9:dd:c25:c25a:d00a:3cb5/1282c19:dd:d9:dd:c25:c25a:d00a:3cb5
1832c19:dd:d9:dd:c25:c25a:d00a:3cb6/1282c19:dd:d9:dd:c25:c25a:d00a:3cb6
1842c19:dd:d9:dd:c25:c25a:d00a:3cb7/1282c19:dd:d9:dd:c25:c25a:d00a:3cb7
1852c19:dd:d9:dd:c25:c25a:d00a:3cb8/1282c19:dd:d9:dd:c25:c25a:d00a:3cb8
1862c19:dd:d9:dd:c25:c25a:d00a:3cb9/1282c19:dd:d9:dd:c25:c25a:d00a:3cb9
1872c19:dd:d9:dd:c25:c25a:d00a:3cba/1282c19:dd:d9:dd:c25:c25a:d00a:3cba
1882c19:dd:d9:dd:c25:c25a:d00a:3cbb/1282c19:dd:d9:dd:c25:c25a:d00a:3cbb
1892c19:dd:d9:dd:c25:c25a:d00a:3cbc/1282c19:dd:d9:dd:c25:c25a:d00a:3cbc
1902c19:dd:d9:dd:c25:c25a:d00a:3cbd/1282c19:dd:d9:dd:c25:c25a:d00a:3cbd
1912c19:dd:d9:dd:c25:c25a:d00a:3cbe/1282c19:dd:d9:dd:c25:c25a:d00a:3cbe
1922c19:dd:d9:dd:c25:c25a:d00a:3cbf/1282c19:dd:d9:dd:c25:c25a:d00a:3cbf
1932c19:dd:d9:dd:c25:c25a:d00a:3cc0/1282c19:dd:d9:dd:c25:c25a:d00a:3cc0
1942c19:dd:d9:dd:c25:c25a:d00a:3cc1/1282c19:dd:d9:dd:c25:c25a:d00a:3cc1
1952c19:dd:d9:dd:c25:c25a:d00a:3cc2/1282c19:dd:d9:dd:c25:c25a:d00a:3cc2
1962c19:dd:d9:dd:c25:c25a:d00a:3cc3/1282c19:dd:d9:dd:c25:c25a:d00a:3cc3
1972c19:dd:d9:dd:c25:c25a:d00a:3cc4/1282c19:dd:d9:dd:c25:c25a:d00a:3cc4
1982c19:dd:d9:dd:c25:c25a:d00a:3cc5/1282c19:dd:d9:dd:c25:c25a:d00a:3cc5
1992c19:dd:d9:dd:c25:c25a:d00a:3cc6/1282c19:dd:d9:dd:c25:c25a:d00a:3cc6
2002c19:dd:d9:dd:c25:c25a:d00a:3cc7/1282c19:dd:d9:dd:c25:c25a:d00a:3cc7
2012c19:dd:d9:dd:c25:c25a:d00a:3cc8/1282c19:dd:d9:dd:c25:c25a:d00a:3cc8
2022c19:dd:d9:dd:c25:c25a:d00a:3cc9/1282c19:dd:d9:dd:c25:c25a:d00a:3cc9
2032c19:dd:d9:dd:c25:c25a:d00a:3cca/1282c19:dd:d9:dd:c25:c25a:d00a:3cca
2042c19:dd:d9:dd:c25:c25a:d00a:3ccb/1282c19:dd:d9:dd:c25:c25a:d00a:3ccb
2052c19:dd:d9:dd:c25:c25a:d00a:3ccc/1282c19:dd:d9:dd:c25:c25a:d00a:3ccc
2062c19:dd:d9:dd:c25:c25a:d00a:3ccd/1282c19:dd:d9:dd:c25:c25a:d00a:3ccd
2072c19:dd:d9:dd:c25:c25a:d00a:3cce/1282c19:dd:d9:dd:c25:c25a:d00a:3cce
2082c19:dd:d9:dd:c25:c25a:d00a:3ccf/1282c19:dd:d9:dd:c25:c25a:d00a:3ccf
2092c19:dd:d9:dd:c25:c25a:d00a:3cd0/1282c19:dd:d9:dd:c25:c25a:d00a:3cd0
2102c19:dd:d9:dd:c25:c25a:d00a:3cd1/1282c19:dd:d9:dd:c25:c25a:d00a:3cd1
2112c19:dd:d9:dd:c25:c25a:d00a:3cd2/1282c19:dd:d9:dd:c25:c25a:d00a:3cd2
2122c19:dd:d9:dd:c25:c25a:d00a:3cd3/1282c19:dd:d9:dd:c25:c25a:d00a:3cd3
2132c19:dd:d9:dd:c25:c25a:d00a:3cd4/1282c19:dd:d9:dd:c25:c25a:d00a:3cd4
2142c19:dd:d9:dd:c25:c25a:d00a:3cd5/1282c19:dd:d9:dd:c25:c25a:d00a:3cd5
2152c19:dd:d9:dd:c25:c25a:d00a:3cd6/1282c19:dd:d9:dd:c25:c25a:d00a:3cd6
2162c19:dd:d9:dd:c25:c25a:d00a:3cd7/1282c19:dd:d9:dd:c25:c25a:d00a:3cd7
2172c19:dd:d9:dd:c25:c25a:d00a:3cd8/1282c19:dd:d9:dd:c25:c25a:d00a:3cd8
2182c19:dd:d9:dd:c25:c25a:d00a:3cd9/1282c19:dd:d9:dd:c25:c25a:d00a:3cd9
2192c19:dd:d9:dd:c25:c25a:d00a:3cda/1282c19:dd:d9:dd:c25:c25a:d00a:3cda
2202c19:dd:d9:dd:c25:c25a:d00a:3cdb/1282c19:dd:d9:dd:c25:c25a:d00a:3cdb
2212c19:dd:d9:dd:c25:c25a:d00a:3cdc/1282c19:dd:d9:dd:c25:c25a:d00a:3cdc
2222c19:dd:d9:dd:c25:c25a:d00a:3cdd/1282c19:dd:d9:dd:c25:c25a:d00a:3cdd
2232c19:dd:d9:dd:c25:c25a:d00a:3cde/1282c19:dd:d9:dd:c25:c25a:d00a:3cde
2242c19:dd:d9:dd:c25:c25a:d00a:3cdf/1282c19:dd:d9:dd:c25:c25a:d00a:3cdf
2252c19:dd:d9:dd:c25:c25a:d00a:3ce0/1282c19:dd:d9:dd:c25:c25a:d00a:3ce0
2262c19:dd:d9:dd:c25:c25a:d00a:3ce1/1282c19:dd:d9:dd:c25:c25a:d00a:3ce1
2272c19:dd:d9:dd:c25:c25a:d00a:3ce2/1282c19:dd:d9:dd:c25:c25a:d00a:3ce2
2282c19:dd:d9:dd:c25:c25a:d00a:3ce3/1282c19:dd:d9:dd:c25:c25a:d00a:3ce3
2292c19:dd:d9:dd:c25:c25a:d00a:3ce4/1282c19:dd:d9:dd:c25:c25a:d00a:3ce4
2302c19:dd:d9:dd:c25:c25a:d00a:3ce5/1282c19:dd:d9:dd:c25:c25a:d00a:3ce5
2312c19:dd:d9:dd:c25:c25a:d00a:3ce6/1282c19:dd:d9:dd:c25:c25a:d00a:3ce6
2322c19:dd:d9:dd:c25:c25a:d00a:3ce7/1282c19:dd:d9:dd:c25:c25a:d00a:3ce7
2332c19:dd:d9:dd:c25:c25a:d00a:3ce8/1282c19:dd:d9:dd:c25:c25a:d00a:3ce8
2342c19:dd:d9:dd:c25:c25a:d00a:3ce9/1282c19:dd:d9:dd:c25:c25a:d00a:3ce9
2352c19:dd:d9:dd:c25:c25a:d00a:3cea/1282c19:dd:d9:dd:c25:c25a:d00a:3cea
2362c19:dd:d9:dd:c25:c25a:d00a:3ceb/1282c19:dd:d9:dd:c25:c25a:d00a:3ceb
2372c19:dd:d9:dd:c25:c25a:d00a:3cec/1282c19:dd:d9:dd:c25:c25a:d00a:3cec
2382c19:dd:d9:dd:c25:c25a:d00a:3ced/1282c19:dd:d9:dd:c25:c25a:d00a:3ced
2392c19:dd:d9:dd:c25:c25a:d00a:3cee/1282c19:dd:d9:dd:c25:c25a:d00a:3cee
2402c19:dd:d9:dd:c25:c25a:d00a:3cef/1282c19:dd:d9:dd:c25:c25a:d00a:3cef
2412c19:dd:d9:dd:c25:c25a:d00a:3cf0/1282c19:dd:d9:dd:c25:c25a:d00a:3cf0
2422c19:dd:d9:dd:c25:c25a:d00a:3cf1/1282c19:dd:d9:dd:c25:c25a:d00a:3cf1
2432c19:dd:d9:dd:c25:c25a:d00a:3cf2/1282c19:dd:d9:dd:c25:c25a:d00a:3cf2
2442c19:dd:d9:dd:c25:c25a:d00a:3cf3/1282c19:dd:d9:dd:c25:c25a:d00a:3cf3
2452c19:dd:d9:dd:c25:c25a:d00a:3cf4/1282c19:dd:d9:dd:c25:c25a:d00a:3cf4
2462c19:dd:d9:dd:c25:c25a:d00a:3cf5/1282c19:dd:d9:dd:c25:c25a:d00a:3cf5
2472c19:dd:d9:dd:c25:c25a:d00a:3cf6/1282c19:dd:d9:dd:c25:c25a:d00a:3cf6
2482c19:dd:d9:dd:c25:c25a:d00a:3cf7/1282c19:dd:d9:dd:c25:c25a:d00a:3cf7
2492c19:dd:d9:dd:c25:c25a:d00a:3cf8/1282c19:dd:d9:dd:c25:c25a:d00a:3cf8
2502c19:dd:d9:dd:c25:c25a:d00a:3cf9/1282c19:dd:d9:dd:c25:c25a:d00a:3cf9
2512c19:dd:d9:dd:c25:c25a:d00a:3cfa/1282c19:dd:d9:dd:c25:c25a:d00a:3cfa
2522c19:dd:d9:dd:c25:c25a:d00a:3cfb/1282c19:dd:d9:dd:c25:c25a:d00a:3cfb
2532c19:dd:d9:dd:c25:c25a:d00a:3cfc/1282c19:dd:d9:dd:c25:c25a:d00a:3cfc
2542c19:dd:d9:dd:c25:c25a:d00a:3cfd/1282c19:dd:d9:dd:c25:c25a:d00a:3cfd
2552c19:dd:d9:dd:c25:c25a:d00a:3cfe/1282c19:dd:d9:dd:c25:c25a:d00a:3cfe
2562c19:dd:d9:dd:c25:c25a:d00a:3cff/1282c19:dd:d9:dd:c25:c25a:d00a:3cff

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.