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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:7c00/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:7c00
Last address
2c19:dd:d9:dd:c25:c25a:d00a:7cff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:7c00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
c.7.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:7c00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:7c00/1282c19:dd:d9:dd:c25:c25a:d00a:7c00
22c19:dd:d9:dd:c25:c25a:d00a:7c01/1282c19:dd:d9:dd:c25:c25a:d00a:7c01
32c19:dd:d9:dd:c25:c25a:d00a:7c02/1282c19:dd:d9:dd:c25:c25a:d00a:7c02
42c19:dd:d9:dd:c25:c25a:d00a:7c03/1282c19:dd:d9:dd:c25:c25a:d00a:7c03
52c19:dd:d9:dd:c25:c25a:d00a:7c04/1282c19:dd:d9:dd:c25:c25a:d00a:7c04
62c19:dd:d9:dd:c25:c25a:d00a:7c05/1282c19:dd:d9:dd:c25:c25a:d00a:7c05
72c19:dd:d9:dd:c25:c25a:d00a:7c06/1282c19:dd:d9:dd:c25:c25a:d00a:7c06
82c19:dd:d9:dd:c25:c25a:d00a:7c07/1282c19:dd:d9:dd:c25:c25a:d00a:7c07
92c19:dd:d9:dd:c25:c25a:d00a:7c08/1282c19:dd:d9:dd:c25:c25a:d00a:7c08
102c19:dd:d9:dd:c25:c25a:d00a:7c09/1282c19:dd:d9:dd:c25:c25a:d00a:7c09
112c19:dd:d9:dd:c25:c25a:d00a:7c0a/1282c19:dd:d9:dd:c25:c25a:d00a:7c0a
122c19:dd:d9:dd:c25:c25a:d00a:7c0b/1282c19:dd:d9:dd:c25:c25a:d00a:7c0b
132c19:dd:d9:dd:c25:c25a:d00a:7c0c/1282c19:dd:d9:dd:c25:c25a:d00a:7c0c
142c19:dd:d9:dd:c25:c25a:d00a:7c0d/1282c19:dd:d9:dd:c25:c25a:d00a:7c0d
152c19:dd:d9:dd:c25:c25a:d00a:7c0e/1282c19:dd:d9:dd:c25:c25a:d00a:7c0e
162c19:dd:d9:dd:c25:c25a:d00a:7c0f/1282c19:dd:d9:dd:c25:c25a:d00a:7c0f
172c19:dd:d9:dd:c25:c25a:d00a:7c10/1282c19:dd:d9:dd:c25:c25a:d00a:7c10
182c19:dd:d9:dd:c25:c25a:d00a:7c11/1282c19:dd:d9:dd:c25:c25a:d00a:7c11
192c19:dd:d9:dd:c25:c25a:d00a:7c12/1282c19:dd:d9:dd:c25:c25a:d00a:7c12
202c19:dd:d9:dd:c25:c25a:d00a:7c13/1282c19:dd:d9:dd:c25:c25a:d00a:7c13
212c19:dd:d9:dd:c25:c25a:d00a:7c14/1282c19:dd:d9:dd:c25:c25a:d00a:7c14
222c19:dd:d9:dd:c25:c25a:d00a:7c15/1282c19:dd:d9:dd:c25:c25a:d00a:7c15
232c19:dd:d9:dd:c25:c25a:d00a:7c16/1282c19:dd:d9:dd:c25:c25a:d00a:7c16
242c19:dd:d9:dd:c25:c25a:d00a:7c17/1282c19:dd:d9:dd:c25:c25a:d00a:7c17
252c19:dd:d9:dd:c25:c25a:d00a:7c18/1282c19:dd:d9:dd:c25:c25a:d00a:7c18
262c19:dd:d9:dd:c25:c25a:d00a:7c19/1282c19:dd:d9:dd:c25:c25a:d00a:7c19
272c19:dd:d9:dd:c25:c25a:d00a:7c1a/1282c19:dd:d9:dd:c25:c25a:d00a:7c1a
282c19:dd:d9:dd:c25:c25a:d00a:7c1b/1282c19:dd:d9:dd:c25:c25a:d00a:7c1b
292c19:dd:d9:dd:c25:c25a:d00a:7c1c/1282c19:dd:d9:dd:c25:c25a:d00a:7c1c
302c19:dd:d9:dd:c25:c25a:d00a:7c1d/1282c19:dd:d9:dd:c25:c25a:d00a:7c1d
312c19:dd:d9:dd:c25:c25a:d00a:7c1e/1282c19:dd:d9:dd:c25:c25a:d00a:7c1e
322c19:dd:d9:dd:c25:c25a:d00a:7c1f/1282c19:dd:d9:dd:c25:c25a:d00a:7c1f
332c19:dd:d9:dd:c25:c25a:d00a:7c20/1282c19:dd:d9:dd:c25:c25a:d00a:7c20
342c19:dd:d9:dd:c25:c25a:d00a:7c21/1282c19:dd:d9:dd:c25:c25a:d00a:7c21
352c19:dd:d9:dd:c25:c25a:d00a:7c22/1282c19:dd:d9:dd:c25:c25a:d00a:7c22
362c19:dd:d9:dd:c25:c25a:d00a:7c23/1282c19:dd:d9:dd:c25:c25a:d00a:7c23
372c19:dd:d9:dd:c25:c25a:d00a:7c24/1282c19:dd:d9:dd:c25:c25a:d00a:7c24
382c19:dd:d9:dd:c25:c25a:d00a:7c25/1282c19:dd:d9:dd:c25:c25a:d00a:7c25
392c19:dd:d9:dd:c25:c25a:d00a:7c26/1282c19:dd:d9:dd:c25:c25a:d00a:7c26
402c19:dd:d9:dd:c25:c25a:d00a:7c27/1282c19:dd:d9:dd:c25:c25a:d00a:7c27
412c19:dd:d9:dd:c25:c25a:d00a:7c28/1282c19:dd:d9:dd:c25:c25a:d00a:7c28
422c19:dd:d9:dd:c25:c25a:d00a:7c29/1282c19:dd:d9:dd:c25:c25a:d00a:7c29
432c19:dd:d9:dd:c25:c25a:d00a:7c2a/1282c19:dd:d9:dd:c25:c25a:d00a:7c2a
442c19:dd:d9:dd:c25:c25a:d00a:7c2b/1282c19:dd:d9:dd:c25:c25a:d00a:7c2b
452c19:dd:d9:dd:c25:c25a:d00a:7c2c/1282c19:dd:d9:dd:c25:c25a:d00a:7c2c
462c19:dd:d9:dd:c25:c25a:d00a:7c2d/1282c19:dd:d9:dd:c25:c25a:d00a:7c2d
472c19:dd:d9:dd:c25:c25a:d00a:7c2e/1282c19:dd:d9:dd:c25:c25a:d00a:7c2e
482c19:dd:d9:dd:c25:c25a:d00a:7c2f/1282c19:dd:d9:dd:c25:c25a:d00a:7c2f
492c19:dd:d9:dd:c25:c25a:d00a:7c30/1282c19:dd:d9:dd:c25:c25a:d00a:7c30
502c19:dd:d9:dd:c25:c25a:d00a:7c31/1282c19:dd:d9:dd:c25:c25a:d00a:7c31
512c19:dd:d9:dd:c25:c25a:d00a:7c32/1282c19:dd:d9:dd:c25:c25a:d00a:7c32
522c19:dd:d9:dd:c25:c25a:d00a:7c33/1282c19:dd:d9:dd:c25:c25a:d00a:7c33
532c19:dd:d9:dd:c25:c25a:d00a:7c34/1282c19:dd:d9:dd:c25:c25a:d00a:7c34
542c19:dd:d9:dd:c25:c25a:d00a:7c35/1282c19:dd:d9:dd:c25:c25a:d00a:7c35
552c19:dd:d9:dd:c25:c25a:d00a:7c36/1282c19:dd:d9:dd:c25:c25a:d00a:7c36
562c19:dd:d9:dd:c25:c25a:d00a:7c37/1282c19:dd:d9:dd:c25:c25a:d00a:7c37
572c19:dd:d9:dd:c25:c25a:d00a:7c38/1282c19:dd:d9:dd:c25:c25a:d00a:7c38
582c19:dd:d9:dd:c25:c25a:d00a:7c39/1282c19:dd:d9:dd:c25:c25a:d00a:7c39
592c19:dd:d9:dd:c25:c25a:d00a:7c3a/1282c19:dd:d9:dd:c25:c25a:d00a:7c3a
602c19:dd:d9:dd:c25:c25a:d00a:7c3b/1282c19:dd:d9:dd:c25:c25a:d00a:7c3b
612c19:dd:d9:dd:c25:c25a:d00a:7c3c/1282c19:dd:d9:dd:c25:c25a:d00a:7c3c
622c19:dd:d9:dd:c25:c25a:d00a:7c3d/1282c19:dd:d9:dd:c25:c25a:d00a:7c3d
632c19:dd:d9:dd:c25:c25a:d00a:7c3e/1282c19:dd:d9:dd:c25:c25a:d00a:7c3e
642c19:dd:d9:dd:c25:c25a:d00a:7c3f/1282c19:dd:d9:dd:c25:c25a:d00a:7c3f
652c19:dd:d9:dd:c25:c25a:d00a:7c40/1282c19:dd:d9:dd:c25:c25a:d00a:7c40
662c19:dd:d9:dd:c25:c25a:d00a:7c41/1282c19:dd:d9:dd:c25:c25a:d00a:7c41
672c19:dd:d9:dd:c25:c25a:d00a:7c42/1282c19:dd:d9:dd:c25:c25a:d00a:7c42
682c19:dd:d9:dd:c25:c25a:d00a:7c43/1282c19:dd:d9:dd:c25:c25a:d00a:7c43
692c19:dd:d9:dd:c25:c25a:d00a:7c44/1282c19:dd:d9:dd:c25:c25a:d00a:7c44
702c19:dd:d9:dd:c25:c25a:d00a:7c45/1282c19:dd:d9:dd:c25:c25a:d00a:7c45
712c19:dd:d9:dd:c25:c25a:d00a:7c46/1282c19:dd:d9:dd:c25:c25a:d00a:7c46
722c19:dd:d9:dd:c25:c25a:d00a:7c47/1282c19:dd:d9:dd:c25:c25a:d00a:7c47
732c19:dd:d9:dd:c25:c25a:d00a:7c48/1282c19:dd:d9:dd:c25:c25a:d00a:7c48
742c19:dd:d9:dd:c25:c25a:d00a:7c49/1282c19:dd:d9:dd:c25:c25a:d00a:7c49
752c19:dd:d9:dd:c25:c25a:d00a:7c4a/1282c19:dd:d9:dd:c25:c25a:d00a:7c4a
762c19:dd:d9:dd:c25:c25a:d00a:7c4b/1282c19:dd:d9:dd:c25:c25a:d00a:7c4b
772c19:dd:d9:dd:c25:c25a:d00a:7c4c/1282c19:dd:d9:dd:c25:c25a:d00a:7c4c
782c19:dd:d9:dd:c25:c25a:d00a:7c4d/1282c19:dd:d9:dd:c25:c25a:d00a:7c4d
792c19:dd:d9:dd:c25:c25a:d00a:7c4e/1282c19:dd:d9:dd:c25:c25a:d00a:7c4e
802c19:dd:d9:dd:c25:c25a:d00a:7c4f/1282c19:dd:d9:dd:c25:c25a:d00a:7c4f
812c19:dd:d9:dd:c25:c25a:d00a:7c50/1282c19:dd:d9:dd:c25:c25a:d00a:7c50
822c19:dd:d9:dd:c25:c25a:d00a:7c51/1282c19:dd:d9:dd:c25:c25a:d00a:7c51
832c19:dd:d9:dd:c25:c25a:d00a:7c52/1282c19:dd:d9:dd:c25:c25a:d00a:7c52
842c19:dd:d9:dd:c25:c25a:d00a:7c53/1282c19:dd:d9:dd:c25:c25a:d00a:7c53
852c19:dd:d9:dd:c25:c25a:d00a:7c54/1282c19:dd:d9:dd:c25:c25a:d00a:7c54
862c19:dd:d9:dd:c25:c25a:d00a:7c55/1282c19:dd:d9:dd:c25:c25a:d00a:7c55
872c19:dd:d9:dd:c25:c25a:d00a:7c56/1282c19:dd:d9:dd:c25:c25a:d00a:7c56
882c19:dd:d9:dd:c25:c25a:d00a:7c57/1282c19:dd:d9:dd:c25:c25a:d00a:7c57
892c19:dd:d9:dd:c25:c25a:d00a:7c58/1282c19:dd:d9:dd:c25:c25a:d00a:7c58
902c19:dd:d9:dd:c25:c25a:d00a:7c59/1282c19:dd:d9:dd:c25:c25a:d00a:7c59
912c19:dd:d9:dd:c25:c25a:d00a:7c5a/1282c19:dd:d9:dd:c25:c25a:d00a:7c5a
922c19:dd:d9:dd:c25:c25a:d00a:7c5b/1282c19:dd:d9:dd:c25:c25a:d00a:7c5b
932c19:dd:d9:dd:c25:c25a:d00a:7c5c/1282c19:dd:d9:dd:c25:c25a:d00a:7c5c
942c19:dd:d9:dd:c25:c25a:d00a:7c5d/1282c19:dd:d9:dd:c25:c25a:d00a:7c5d
952c19:dd:d9:dd:c25:c25a:d00a:7c5e/1282c19:dd:d9:dd:c25:c25a:d00a:7c5e
962c19:dd:d9:dd:c25:c25a:d00a:7c5f/1282c19:dd:d9:dd:c25:c25a:d00a:7c5f
972c19:dd:d9:dd:c25:c25a:d00a:7c60/1282c19:dd:d9:dd:c25:c25a:d00a:7c60
982c19:dd:d9:dd:c25:c25a:d00a:7c61/1282c19:dd:d9:dd:c25:c25a:d00a:7c61
992c19:dd:d9:dd:c25:c25a:d00a:7c62/1282c19:dd:d9:dd:c25:c25a:d00a:7c62
1002c19:dd:d9:dd:c25:c25a:d00a:7c63/1282c19:dd:d9:dd:c25:c25a:d00a:7c63
1012c19:dd:d9:dd:c25:c25a:d00a:7c64/1282c19:dd:d9:dd:c25:c25a:d00a:7c64
1022c19:dd:d9:dd:c25:c25a:d00a:7c65/1282c19:dd:d9:dd:c25:c25a:d00a:7c65
1032c19:dd:d9:dd:c25:c25a:d00a:7c66/1282c19:dd:d9:dd:c25:c25a:d00a:7c66
1042c19:dd:d9:dd:c25:c25a:d00a:7c67/1282c19:dd:d9:dd:c25:c25a:d00a:7c67
1052c19:dd:d9:dd:c25:c25a:d00a:7c68/1282c19:dd:d9:dd:c25:c25a:d00a:7c68
1062c19:dd:d9:dd:c25:c25a:d00a:7c69/1282c19:dd:d9:dd:c25:c25a:d00a:7c69
1072c19:dd:d9:dd:c25:c25a:d00a:7c6a/1282c19:dd:d9:dd:c25:c25a:d00a:7c6a
1082c19:dd:d9:dd:c25:c25a:d00a:7c6b/1282c19:dd:d9:dd:c25:c25a:d00a:7c6b
1092c19:dd:d9:dd:c25:c25a:d00a:7c6c/1282c19:dd:d9:dd:c25:c25a:d00a:7c6c
1102c19:dd:d9:dd:c25:c25a:d00a:7c6d/1282c19:dd:d9:dd:c25:c25a:d00a:7c6d
1112c19:dd:d9:dd:c25:c25a:d00a:7c6e/1282c19:dd:d9:dd:c25:c25a:d00a:7c6e
1122c19:dd:d9:dd:c25:c25a:d00a:7c6f/1282c19:dd:d9:dd:c25:c25a:d00a:7c6f
1132c19:dd:d9:dd:c25:c25a:d00a:7c70/1282c19:dd:d9:dd:c25:c25a:d00a:7c70
1142c19:dd:d9:dd:c25:c25a:d00a:7c71/1282c19:dd:d9:dd:c25:c25a:d00a:7c71
1152c19:dd:d9:dd:c25:c25a:d00a:7c72/1282c19:dd:d9:dd:c25:c25a:d00a:7c72
1162c19:dd:d9:dd:c25:c25a:d00a:7c73/1282c19:dd:d9:dd:c25:c25a:d00a:7c73
1172c19:dd:d9:dd:c25:c25a:d00a:7c74/1282c19:dd:d9:dd:c25:c25a:d00a:7c74
1182c19:dd:d9:dd:c25:c25a:d00a:7c75/1282c19:dd:d9:dd:c25:c25a:d00a:7c75
1192c19:dd:d9:dd:c25:c25a:d00a:7c76/1282c19:dd:d9:dd:c25:c25a:d00a:7c76
1202c19:dd:d9:dd:c25:c25a:d00a:7c77/1282c19:dd:d9:dd:c25:c25a:d00a:7c77
1212c19:dd:d9:dd:c25:c25a:d00a:7c78/1282c19:dd:d9:dd:c25:c25a:d00a:7c78
1222c19:dd:d9:dd:c25:c25a:d00a:7c79/1282c19:dd:d9:dd:c25:c25a:d00a:7c79
1232c19:dd:d9:dd:c25:c25a:d00a:7c7a/1282c19:dd:d9:dd:c25:c25a:d00a:7c7a
1242c19:dd:d9:dd:c25:c25a:d00a:7c7b/1282c19:dd:d9:dd:c25:c25a:d00a:7c7b
1252c19:dd:d9:dd:c25:c25a:d00a:7c7c/1282c19:dd:d9:dd:c25:c25a:d00a:7c7c
1262c19:dd:d9:dd:c25:c25a:d00a:7c7d/1282c19:dd:d9:dd:c25:c25a:d00a:7c7d
1272c19:dd:d9:dd:c25:c25a:d00a:7c7e/1282c19:dd:d9:dd:c25:c25a:d00a:7c7e
1282c19:dd:d9:dd:c25:c25a:d00a:7c7f/1282c19:dd:d9:dd:c25:c25a:d00a:7c7f
1292c19:dd:d9:dd:c25:c25a:d00a:7c80/1282c19:dd:d9:dd:c25:c25a:d00a:7c80
1302c19:dd:d9:dd:c25:c25a:d00a:7c81/1282c19:dd:d9:dd:c25:c25a:d00a:7c81
1312c19:dd:d9:dd:c25:c25a:d00a:7c82/1282c19:dd:d9:dd:c25:c25a:d00a:7c82
1322c19:dd:d9:dd:c25:c25a:d00a:7c83/1282c19:dd:d9:dd:c25:c25a:d00a:7c83
1332c19:dd:d9:dd:c25:c25a:d00a:7c84/1282c19:dd:d9:dd:c25:c25a:d00a:7c84
1342c19:dd:d9:dd:c25:c25a:d00a:7c85/1282c19:dd:d9:dd:c25:c25a:d00a:7c85
1352c19:dd:d9:dd:c25:c25a:d00a:7c86/1282c19:dd:d9:dd:c25:c25a:d00a:7c86
1362c19:dd:d9:dd:c25:c25a:d00a:7c87/1282c19:dd:d9:dd:c25:c25a:d00a:7c87
1372c19:dd:d9:dd:c25:c25a:d00a:7c88/1282c19:dd:d9:dd:c25:c25a:d00a:7c88
1382c19:dd:d9:dd:c25:c25a:d00a:7c89/1282c19:dd:d9:dd:c25:c25a:d00a:7c89
1392c19:dd:d9:dd:c25:c25a:d00a:7c8a/1282c19:dd:d9:dd:c25:c25a:d00a:7c8a
1402c19:dd:d9:dd:c25:c25a:d00a:7c8b/1282c19:dd:d9:dd:c25:c25a:d00a:7c8b
1412c19:dd:d9:dd:c25:c25a:d00a:7c8c/1282c19:dd:d9:dd:c25:c25a:d00a:7c8c
1422c19:dd:d9:dd:c25:c25a:d00a:7c8d/1282c19:dd:d9:dd:c25:c25a:d00a:7c8d
1432c19:dd:d9:dd:c25:c25a:d00a:7c8e/1282c19:dd:d9:dd:c25:c25a:d00a:7c8e
1442c19:dd:d9:dd:c25:c25a:d00a:7c8f/1282c19:dd:d9:dd:c25:c25a:d00a:7c8f
1452c19:dd:d9:dd:c25:c25a:d00a:7c90/1282c19:dd:d9:dd:c25:c25a:d00a:7c90
1462c19:dd:d9:dd:c25:c25a:d00a:7c91/1282c19:dd:d9:dd:c25:c25a:d00a:7c91
1472c19:dd:d9:dd:c25:c25a:d00a:7c92/1282c19:dd:d9:dd:c25:c25a:d00a:7c92
1482c19:dd:d9:dd:c25:c25a:d00a:7c93/1282c19:dd:d9:dd:c25:c25a:d00a:7c93
1492c19:dd:d9:dd:c25:c25a:d00a:7c94/1282c19:dd:d9:dd:c25:c25a:d00a:7c94
1502c19:dd:d9:dd:c25:c25a:d00a:7c95/1282c19:dd:d9:dd:c25:c25a:d00a:7c95
1512c19:dd:d9:dd:c25:c25a:d00a:7c96/1282c19:dd:d9:dd:c25:c25a:d00a:7c96
1522c19:dd:d9:dd:c25:c25a:d00a:7c97/1282c19:dd:d9:dd:c25:c25a:d00a:7c97
1532c19:dd:d9:dd:c25:c25a:d00a:7c98/1282c19:dd:d9:dd:c25:c25a:d00a:7c98
1542c19:dd:d9:dd:c25:c25a:d00a:7c99/1282c19:dd:d9:dd:c25:c25a:d00a:7c99
1552c19:dd:d9:dd:c25:c25a:d00a:7c9a/1282c19:dd:d9:dd:c25:c25a:d00a:7c9a
1562c19:dd:d9:dd:c25:c25a:d00a:7c9b/1282c19:dd:d9:dd:c25:c25a:d00a:7c9b
1572c19:dd:d9:dd:c25:c25a:d00a:7c9c/1282c19:dd:d9:dd:c25:c25a:d00a:7c9c
1582c19:dd:d9:dd:c25:c25a:d00a:7c9d/1282c19:dd:d9:dd:c25:c25a:d00a:7c9d
1592c19:dd:d9:dd:c25:c25a:d00a:7c9e/1282c19:dd:d9:dd:c25:c25a:d00a:7c9e
1602c19:dd:d9:dd:c25:c25a:d00a:7c9f/1282c19:dd:d9:dd:c25:c25a:d00a:7c9f
1612c19:dd:d9:dd:c25:c25a:d00a:7ca0/1282c19:dd:d9:dd:c25:c25a:d00a:7ca0
1622c19:dd:d9:dd:c25:c25a:d00a:7ca1/1282c19:dd:d9:dd:c25:c25a:d00a:7ca1
1632c19:dd:d9:dd:c25:c25a:d00a:7ca2/1282c19:dd:d9:dd:c25:c25a:d00a:7ca2
1642c19:dd:d9:dd:c25:c25a:d00a:7ca3/1282c19:dd:d9:dd:c25:c25a:d00a:7ca3
1652c19:dd:d9:dd:c25:c25a:d00a:7ca4/1282c19:dd:d9:dd:c25:c25a:d00a:7ca4
1662c19:dd:d9:dd:c25:c25a:d00a:7ca5/1282c19:dd:d9:dd:c25:c25a:d00a:7ca5
1672c19:dd:d9:dd:c25:c25a:d00a:7ca6/1282c19:dd:d9:dd:c25:c25a:d00a:7ca6
1682c19:dd:d9:dd:c25:c25a:d00a:7ca7/1282c19:dd:d9:dd:c25:c25a:d00a:7ca7
1692c19:dd:d9:dd:c25:c25a:d00a:7ca8/1282c19:dd:d9:dd:c25:c25a:d00a:7ca8
1702c19:dd:d9:dd:c25:c25a:d00a:7ca9/1282c19:dd:d9:dd:c25:c25a:d00a:7ca9
1712c19:dd:d9:dd:c25:c25a:d00a:7caa/1282c19:dd:d9:dd:c25:c25a:d00a:7caa
1722c19:dd:d9:dd:c25:c25a:d00a:7cab/1282c19:dd:d9:dd:c25:c25a:d00a:7cab
1732c19:dd:d9:dd:c25:c25a:d00a:7cac/1282c19:dd:d9:dd:c25:c25a:d00a:7cac
1742c19:dd:d9:dd:c25:c25a:d00a:7cad/1282c19:dd:d9:dd:c25:c25a:d00a:7cad
1752c19:dd:d9:dd:c25:c25a:d00a:7cae/1282c19:dd:d9:dd:c25:c25a:d00a:7cae
1762c19:dd:d9:dd:c25:c25a:d00a:7caf/1282c19:dd:d9:dd:c25:c25a:d00a:7caf
1772c19:dd:d9:dd:c25:c25a:d00a:7cb0/1282c19:dd:d9:dd:c25:c25a:d00a:7cb0
1782c19:dd:d9:dd:c25:c25a:d00a:7cb1/1282c19:dd:d9:dd:c25:c25a:d00a:7cb1
1792c19:dd:d9:dd:c25:c25a:d00a:7cb2/1282c19:dd:d9:dd:c25:c25a:d00a:7cb2
1802c19:dd:d9:dd:c25:c25a:d00a:7cb3/1282c19:dd:d9:dd:c25:c25a:d00a:7cb3
1812c19:dd:d9:dd:c25:c25a:d00a:7cb4/1282c19:dd:d9:dd:c25:c25a:d00a:7cb4
1822c19:dd:d9:dd:c25:c25a:d00a:7cb5/1282c19:dd:d9:dd:c25:c25a:d00a:7cb5
1832c19:dd:d9:dd:c25:c25a:d00a:7cb6/1282c19:dd:d9:dd:c25:c25a:d00a:7cb6
1842c19:dd:d9:dd:c25:c25a:d00a:7cb7/1282c19:dd:d9:dd:c25:c25a:d00a:7cb7
1852c19:dd:d9:dd:c25:c25a:d00a:7cb8/1282c19:dd:d9:dd:c25:c25a:d00a:7cb8
1862c19:dd:d9:dd:c25:c25a:d00a:7cb9/1282c19:dd:d9:dd:c25:c25a:d00a:7cb9
1872c19:dd:d9:dd:c25:c25a:d00a:7cba/1282c19:dd:d9:dd:c25:c25a:d00a:7cba
1882c19:dd:d9:dd:c25:c25a:d00a:7cbb/1282c19:dd:d9:dd:c25:c25a:d00a:7cbb
1892c19:dd:d9:dd:c25:c25a:d00a:7cbc/1282c19:dd:d9:dd:c25:c25a:d00a:7cbc
1902c19:dd:d9:dd:c25:c25a:d00a:7cbd/1282c19:dd:d9:dd:c25:c25a:d00a:7cbd
1912c19:dd:d9:dd:c25:c25a:d00a:7cbe/1282c19:dd:d9:dd:c25:c25a:d00a:7cbe
1922c19:dd:d9:dd:c25:c25a:d00a:7cbf/1282c19:dd:d9:dd:c25:c25a:d00a:7cbf
1932c19:dd:d9:dd:c25:c25a:d00a:7cc0/1282c19:dd:d9:dd:c25:c25a:d00a:7cc0
1942c19:dd:d9:dd:c25:c25a:d00a:7cc1/1282c19:dd:d9:dd:c25:c25a:d00a:7cc1
1952c19:dd:d9:dd:c25:c25a:d00a:7cc2/1282c19:dd:d9:dd:c25:c25a:d00a:7cc2
1962c19:dd:d9:dd:c25:c25a:d00a:7cc3/1282c19:dd:d9:dd:c25:c25a:d00a:7cc3
1972c19:dd:d9:dd:c25:c25a:d00a:7cc4/1282c19:dd:d9:dd:c25:c25a:d00a:7cc4
1982c19:dd:d9:dd:c25:c25a:d00a:7cc5/1282c19:dd:d9:dd:c25:c25a:d00a:7cc5
1992c19:dd:d9:dd:c25:c25a:d00a:7cc6/1282c19:dd:d9:dd:c25:c25a:d00a:7cc6
2002c19:dd:d9:dd:c25:c25a:d00a:7cc7/1282c19:dd:d9:dd:c25:c25a:d00a:7cc7
2012c19:dd:d9:dd:c25:c25a:d00a:7cc8/1282c19:dd:d9:dd:c25:c25a:d00a:7cc8
2022c19:dd:d9:dd:c25:c25a:d00a:7cc9/1282c19:dd:d9:dd:c25:c25a:d00a:7cc9
2032c19:dd:d9:dd:c25:c25a:d00a:7cca/1282c19:dd:d9:dd:c25:c25a:d00a:7cca
2042c19:dd:d9:dd:c25:c25a:d00a:7ccb/1282c19:dd:d9:dd:c25:c25a:d00a:7ccb
2052c19:dd:d9:dd:c25:c25a:d00a:7ccc/1282c19:dd:d9:dd:c25:c25a:d00a:7ccc
2062c19:dd:d9:dd:c25:c25a:d00a:7ccd/1282c19:dd:d9:dd:c25:c25a:d00a:7ccd
2072c19:dd:d9:dd:c25:c25a:d00a:7cce/1282c19:dd:d9:dd:c25:c25a:d00a:7cce
2082c19:dd:d9:dd:c25:c25a:d00a:7ccf/1282c19:dd:d9:dd:c25:c25a:d00a:7ccf
2092c19:dd:d9:dd:c25:c25a:d00a:7cd0/1282c19:dd:d9:dd:c25:c25a:d00a:7cd0
2102c19:dd:d9:dd:c25:c25a:d00a:7cd1/1282c19:dd:d9:dd:c25:c25a:d00a:7cd1
2112c19:dd:d9:dd:c25:c25a:d00a:7cd2/1282c19:dd:d9:dd:c25:c25a:d00a:7cd2
2122c19:dd:d9:dd:c25:c25a:d00a:7cd3/1282c19:dd:d9:dd:c25:c25a:d00a:7cd3
2132c19:dd:d9:dd:c25:c25a:d00a:7cd4/1282c19:dd:d9:dd:c25:c25a:d00a:7cd4
2142c19:dd:d9:dd:c25:c25a:d00a:7cd5/1282c19:dd:d9:dd:c25:c25a:d00a:7cd5
2152c19:dd:d9:dd:c25:c25a:d00a:7cd6/1282c19:dd:d9:dd:c25:c25a:d00a:7cd6
2162c19:dd:d9:dd:c25:c25a:d00a:7cd7/1282c19:dd:d9:dd:c25:c25a:d00a:7cd7
2172c19:dd:d9:dd:c25:c25a:d00a:7cd8/1282c19:dd:d9:dd:c25:c25a:d00a:7cd8
2182c19:dd:d9:dd:c25:c25a:d00a:7cd9/1282c19:dd:d9:dd:c25:c25a:d00a:7cd9
2192c19:dd:d9:dd:c25:c25a:d00a:7cda/1282c19:dd:d9:dd:c25:c25a:d00a:7cda
2202c19:dd:d9:dd:c25:c25a:d00a:7cdb/1282c19:dd:d9:dd:c25:c25a:d00a:7cdb
2212c19:dd:d9:dd:c25:c25a:d00a:7cdc/1282c19:dd:d9:dd:c25:c25a:d00a:7cdc
2222c19:dd:d9:dd:c25:c25a:d00a:7cdd/1282c19:dd:d9:dd:c25:c25a:d00a:7cdd
2232c19:dd:d9:dd:c25:c25a:d00a:7cde/1282c19:dd:d9:dd:c25:c25a:d00a:7cde
2242c19:dd:d9:dd:c25:c25a:d00a:7cdf/1282c19:dd:d9:dd:c25:c25a:d00a:7cdf
2252c19:dd:d9:dd:c25:c25a:d00a:7ce0/1282c19:dd:d9:dd:c25:c25a:d00a:7ce0
2262c19:dd:d9:dd:c25:c25a:d00a:7ce1/1282c19:dd:d9:dd:c25:c25a:d00a:7ce1
2272c19:dd:d9:dd:c25:c25a:d00a:7ce2/1282c19:dd:d9:dd:c25:c25a:d00a:7ce2
2282c19:dd:d9:dd:c25:c25a:d00a:7ce3/1282c19:dd:d9:dd:c25:c25a:d00a:7ce3
2292c19:dd:d9:dd:c25:c25a:d00a:7ce4/1282c19:dd:d9:dd:c25:c25a:d00a:7ce4
2302c19:dd:d9:dd:c25:c25a:d00a:7ce5/1282c19:dd:d9:dd:c25:c25a:d00a:7ce5
2312c19:dd:d9:dd:c25:c25a:d00a:7ce6/1282c19:dd:d9:dd:c25:c25a:d00a:7ce6
2322c19:dd:d9:dd:c25:c25a:d00a:7ce7/1282c19:dd:d9:dd:c25:c25a:d00a:7ce7
2332c19:dd:d9:dd:c25:c25a:d00a:7ce8/1282c19:dd:d9:dd:c25:c25a:d00a:7ce8
2342c19:dd:d9:dd:c25:c25a:d00a:7ce9/1282c19:dd:d9:dd:c25:c25a:d00a:7ce9
2352c19:dd:d9:dd:c25:c25a:d00a:7cea/1282c19:dd:d9:dd:c25:c25a:d00a:7cea
2362c19:dd:d9:dd:c25:c25a:d00a:7ceb/1282c19:dd:d9:dd:c25:c25a:d00a:7ceb
2372c19:dd:d9:dd:c25:c25a:d00a:7cec/1282c19:dd:d9:dd:c25:c25a:d00a:7cec
2382c19:dd:d9:dd:c25:c25a:d00a:7ced/1282c19:dd:d9:dd:c25:c25a:d00a:7ced
2392c19:dd:d9:dd:c25:c25a:d00a:7cee/1282c19:dd:d9:dd:c25:c25a:d00a:7cee
2402c19:dd:d9:dd:c25:c25a:d00a:7cef/1282c19:dd:d9:dd:c25:c25a:d00a:7cef
2412c19:dd:d9:dd:c25:c25a:d00a:7cf0/1282c19:dd:d9:dd:c25:c25a:d00a:7cf0
2422c19:dd:d9:dd:c25:c25a:d00a:7cf1/1282c19:dd:d9:dd:c25:c25a:d00a:7cf1
2432c19:dd:d9:dd:c25:c25a:d00a:7cf2/1282c19:dd:d9:dd:c25:c25a:d00a:7cf2
2442c19:dd:d9:dd:c25:c25a:d00a:7cf3/1282c19:dd:d9:dd:c25:c25a:d00a:7cf3
2452c19:dd:d9:dd:c25:c25a:d00a:7cf4/1282c19:dd:d9:dd:c25:c25a:d00a:7cf4
2462c19:dd:d9:dd:c25:c25a:d00a:7cf5/1282c19:dd:d9:dd:c25:c25a:d00a:7cf5
2472c19:dd:d9:dd:c25:c25a:d00a:7cf6/1282c19:dd:d9:dd:c25:c25a:d00a:7cf6
2482c19:dd:d9:dd:c25:c25a:d00a:7cf7/1282c19:dd:d9:dd:c25:c25a:d00a:7cf7
2492c19:dd:d9:dd:c25:c25a:d00a:7cf8/1282c19:dd:d9:dd:c25:c25a:d00a:7cf8
2502c19:dd:d9:dd:c25:c25a:d00a:7cf9/1282c19:dd:d9:dd:c25:c25a:d00a:7cf9
2512c19:dd:d9:dd:c25:c25a:d00a:7cfa/1282c19:dd:d9:dd:c25:c25a:d00a:7cfa
2522c19:dd:d9:dd:c25:c25a:d00a:7cfb/1282c19:dd:d9:dd:c25:c25a:d00a:7cfb
2532c19:dd:d9:dd:c25:c25a:d00a:7cfc/1282c19:dd:d9:dd:c25:c25a:d00a:7cfc
2542c19:dd:d9:dd:c25:c25a:d00a:7cfd/1282c19:dd:d9:dd:c25:c25a:d00a:7cfd
2552c19:dd:d9:dd:c25:c25a:d00a:7cfe/1282c19:dd:d9:dd:c25:c25a:d00a:7cfe
2562c19:dd:d9:dd:c25:c25a:d00a:7cff/1282c19:dd:d9:dd:c25:c25a:d00a:7cff

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.