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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:1c00/120
First address
2c19:dd:d9:dd:c25:c25:94de:1c00
Last address
2c19:dd:d9:dd:c25:c25:94de:1cff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:1c00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
c.1.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:1c00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:1c00/1282c19:dd:d9:dd:c25:c25:94de:1c00
22c19:dd:d9:dd:c25:c25:94de:1c01/1282c19:dd:d9:dd:c25:c25:94de:1c01
32c19:dd:d9:dd:c25:c25:94de:1c02/1282c19:dd:d9:dd:c25:c25:94de:1c02
42c19:dd:d9:dd:c25:c25:94de:1c03/1282c19:dd:d9:dd:c25:c25:94de:1c03
52c19:dd:d9:dd:c25:c25:94de:1c04/1282c19:dd:d9:dd:c25:c25:94de:1c04
62c19:dd:d9:dd:c25:c25:94de:1c05/1282c19:dd:d9:dd:c25:c25:94de:1c05
72c19:dd:d9:dd:c25:c25:94de:1c06/1282c19:dd:d9:dd:c25:c25:94de:1c06
82c19:dd:d9:dd:c25:c25:94de:1c07/1282c19:dd:d9:dd:c25:c25:94de:1c07
92c19:dd:d9:dd:c25:c25:94de:1c08/1282c19:dd:d9:dd:c25:c25:94de:1c08
102c19:dd:d9:dd:c25:c25:94de:1c09/1282c19:dd:d9:dd:c25:c25:94de:1c09
112c19:dd:d9:dd:c25:c25:94de:1c0a/1282c19:dd:d9:dd:c25:c25:94de:1c0a
122c19:dd:d9:dd:c25:c25:94de:1c0b/1282c19:dd:d9:dd:c25:c25:94de:1c0b
132c19:dd:d9:dd:c25:c25:94de:1c0c/1282c19:dd:d9:dd:c25:c25:94de:1c0c
142c19:dd:d9:dd:c25:c25:94de:1c0d/1282c19:dd:d9:dd:c25:c25:94de:1c0d
152c19:dd:d9:dd:c25:c25:94de:1c0e/1282c19:dd:d9:dd:c25:c25:94de:1c0e
162c19:dd:d9:dd:c25:c25:94de:1c0f/1282c19:dd:d9:dd:c25:c25:94de:1c0f
172c19:dd:d9:dd:c25:c25:94de:1c10/1282c19:dd:d9:dd:c25:c25:94de:1c10
182c19:dd:d9:dd:c25:c25:94de:1c11/1282c19:dd:d9:dd:c25:c25:94de:1c11
192c19:dd:d9:dd:c25:c25:94de:1c12/1282c19:dd:d9:dd:c25:c25:94de:1c12
202c19:dd:d9:dd:c25:c25:94de:1c13/1282c19:dd:d9:dd:c25:c25:94de:1c13
212c19:dd:d9:dd:c25:c25:94de:1c14/1282c19:dd:d9:dd:c25:c25:94de:1c14
222c19:dd:d9:dd:c25:c25:94de:1c15/1282c19:dd:d9:dd:c25:c25:94de:1c15
232c19:dd:d9:dd:c25:c25:94de:1c16/1282c19:dd:d9:dd:c25:c25:94de:1c16
242c19:dd:d9:dd:c25:c25:94de:1c17/1282c19:dd:d9:dd:c25:c25:94de:1c17
252c19:dd:d9:dd:c25:c25:94de:1c18/1282c19:dd:d9:dd:c25:c25:94de:1c18
262c19:dd:d9:dd:c25:c25:94de:1c19/1282c19:dd:d9:dd:c25:c25:94de:1c19
272c19:dd:d9:dd:c25:c25:94de:1c1a/1282c19:dd:d9:dd:c25:c25:94de:1c1a
282c19:dd:d9:dd:c25:c25:94de:1c1b/1282c19:dd:d9:dd:c25:c25:94de:1c1b
292c19:dd:d9:dd:c25:c25:94de:1c1c/1282c19:dd:d9:dd:c25:c25:94de:1c1c
302c19:dd:d9:dd:c25:c25:94de:1c1d/1282c19:dd:d9:dd:c25:c25:94de:1c1d
312c19:dd:d9:dd:c25:c25:94de:1c1e/1282c19:dd:d9:dd:c25:c25:94de:1c1e
322c19:dd:d9:dd:c25:c25:94de:1c1f/1282c19:dd:d9:dd:c25:c25:94de:1c1f
332c19:dd:d9:dd:c25:c25:94de:1c20/1282c19:dd:d9:dd:c25:c25:94de:1c20
342c19:dd:d9:dd:c25:c25:94de:1c21/1282c19:dd:d9:dd:c25:c25:94de:1c21
352c19:dd:d9:dd:c25:c25:94de:1c22/1282c19:dd:d9:dd:c25:c25:94de:1c22
362c19:dd:d9:dd:c25:c25:94de:1c23/1282c19:dd:d9:dd:c25:c25:94de:1c23
372c19:dd:d9:dd:c25:c25:94de:1c24/1282c19:dd:d9:dd:c25:c25:94de:1c24
382c19:dd:d9:dd:c25:c25:94de:1c25/1282c19:dd:d9:dd:c25:c25:94de:1c25
392c19:dd:d9:dd:c25:c25:94de:1c26/1282c19:dd:d9:dd:c25:c25:94de:1c26
402c19:dd:d9:dd:c25:c25:94de:1c27/1282c19:dd:d9:dd:c25:c25:94de:1c27
412c19:dd:d9:dd:c25:c25:94de:1c28/1282c19:dd:d9:dd:c25:c25:94de:1c28
422c19:dd:d9:dd:c25:c25:94de:1c29/1282c19:dd:d9:dd:c25:c25:94de:1c29
432c19:dd:d9:dd:c25:c25:94de:1c2a/1282c19:dd:d9:dd:c25:c25:94de:1c2a
442c19:dd:d9:dd:c25:c25:94de:1c2b/1282c19:dd:d9:dd:c25:c25:94de:1c2b
452c19:dd:d9:dd:c25:c25:94de:1c2c/1282c19:dd:d9:dd:c25:c25:94de:1c2c
462c19:dd:d9:dd:c25:c25:94de:1c2d/1282c19:dd:d9:dd:c25:c25:94de:1c2d
472c19:dd:d9:dd:c25:c25:94de:1c2e/1282c19:dd:d9:dd:c25:c25:94de:1c2e
482c19:dd:d9:dd:c25:c25:94de:1c2f/1282c19:dd:d9:dd:c25:c25:94de:1c2f
492c19:dd:d9:dd:c25:c25:94de:1c30/1282c19:dd:d9:dd:c25:c25:94de:1c30
502c19:dd:d9:dd:c25:c25:94de:1c31/1282c19:dd:d9:dd:c25:c25:94de:1c31
512c19:dd:d9:dd:c25:c25:94de:1c32/1282c19:dd:d9:dd:c25:c25:94de:1c32
522c19:dd:d9:dd:c25:c25:94de:1c33/1282c19:dd:d9:dd:c25:c25:94de:1c33
532c19:dd:d9:dd:c25:c25:94de:1c34/1282c19:dd:d9:dd:c25:c25:94de:1c34
542c19:dd:d9:dd:c25:c25:94de:1c35/1282c19:dd:d9:dd:c25:c25:94de:1c35
552c19:dd:d9:dd:c25:c25:94de:1c36/1282c19:dd:d9:dd:c25:c25:94de:1c36
562c19:dd:d9:dd:c25:c25:94de:1c37/1282c19:dd:d9:dd:c25:c25:94de:1c37
572c19:dd:d9:dd:c25:c25:94de:1c38/1282c19:dd:d9:dd:c25:c25:94de:1c38
582c19:dd:d9:dd:c25:c25:94de:1c39/1282c19:dd:d9:dd:c25:c25:94de:1c39
592c19:dd:d9:dd:c25:c25:94de:1c3a/1282c19:dd:d9:dd:c25:c25:94de:1c3a
602c19:dd:d9:dd:c25:c25:94de:1c3b/1282c19:dd:d9:dd:c25:c25:94de:1c3b
612c19:dd:d9:dd:c25:c25:94de:1c3c/1282c19:dd:d9:dd:c25:c25:94de:1c3c
622c19:dd:d9:dd:c25:c25:94de:1c3d/1282c19:dd:d9:dd:c25:c25:94de:1c3d
632c19:dd:d9:dd:c25:c25:94de:1c3e/1282c19:dd:d9:dd:c25:c25:94de:1c3e
642c19:dd:d9:dd:c25:c25:94de:1c3f/1282c19:dd:d9:dd:c25:c25:94de:1c3f
652c19:dd:d9:dd:c25:c25:94de:1c40/1282c19:dd:d9:dd:c25:c25:94de:1c40
662c19:dd:d9:dd:c25:c25:94de:1c41/1282c19:dd:d9:dd:c25:c25:94de:1c41
672c19:dd:d9:dd:c25:c25:94de:1c42/1282c19:dd:d9:dd:c25:c25:94de:1c42
682c19:dd:d9:dd:c25:c25:94de:1c43/1282c19:dd:d9:dd:c25:c25:94de:1c43
692c19:dd:d9:dd:c25:c25:94de:1c44/1282c19:dd:d9:dd:c25:c25:94de:1c44
702c19:dd:d9:dd:c25:c25:94de:1c45/1282c19:dd:d9:dd:c25:c25:94de:1c45
712c19:dd:d9:dd:c25:c25:94de:1c46/1282c19:dd:d9:dd:c25:c25:94de:1c46
722c19:dd:d9:dd:c25:c25:94de:1c47/1282c19:dd:d9:dd:c25:c25:94de:1c47
732c19:dd:d9:dd:c25:c25:94de:1c48/1282c19:dd:d9:dd:c25:c25:94de:1c48
742c19:dd:d9:dd:c25:c25:94de:1c49/1282c19:dd:d9:dd:c25:c25:94de:1c49
752c19:dd:d9:dd:c25:c25:94de:1c4a/1282c19:dd:d9:dd:c25:c25:94de:1c4a
762c19:dd:d9:dd:c25:c25:94de:1c4b/1282c19:dd:d9:dd:c25:c25:94de:1c4b
772c19:dd:d9:dd:c25:c25:94de:1c4c/1282c19:dd:d9:dd:c25:c25:94de:1c4c
782c19:dd:d9:dd:c25:c25:94de:1c4d/1282c19:dd:d9:dd:c25:c25:94de:1c4d
792c19:dd:d9:dd:c25:c25:94de:1c4e/1282c19:dd:d9:dd:c25:c25:94de:1c4e
802c19:dd:d9:dd:c25:c25:94de:1c4f/1282c19:dd:d9:dd:c25:c25:94de:1c4f
812c19:dd:d9:dd:c25:c25:94de:1c50/1282c19:dd:d9:dd:c25:c25:94de:1c50
822c19:dd:d9:dd:c25:c25:94de:1c51/1282c19:dd:d9:dd:c25:c25:94de:1c51
832c19:dd:d9:dd:c25:c25:94de:1c52/1282c19:dd:d9:dd:c25:c25:94de:1c52
842c19:dd:d9:dd:c25:c25:94de:1c53/1282c19:dd:d9:dd:c25:c25:94de:1c53
852c19:dd:d9:dd:c25:c25:94de:1c54/1282c19:dd:d9:dd:c25:c25:94de:1c54
862c19:dd:d9:dd:c25:c25:94de:1c55/1282c19:dd:d9:dd:c25:c25:94de:1c55
872c19:dd:d9:dd:c25:c25:94de:1c56/1282c19:dd:d9:dd:c25:c25:94de:1c56
882c19:dd:d9:dd:c25:c25:94de:1c57/1282c19:dd:d9:dd:c25:c25:94de:1c57
892c19:dd:d9:dd:c25:c25:94de:1c58/1282c19:dd:d9:dd:c25:c25:94de:1c58
902c19:dd:d9:dd:c25:c25:94de:1c59/1282c19:dd:d9:dd:c25:c25:94de:1c59
912c19:dd:d9:dd:c25:c25:94de:1c5a/1282c19:dd:d9:dd:c25:c25:94de:1c5a
922c19:dd:d9:dd:c25:c25:94de:1c5b/1282c19:dd:d9:dd:c25:c25:94de:1c5b
932c19:dd:d9:dd:c25:c25:94de:1c5c/1282c19:dd:d9:dd:c25:c25:94de:1c5c
942c19:dd:d9:dd:c25:c25:94de:1c5d/1282c19:dd:d9:dd:c25:c25:94de:1c5d
952c19:dd:d9:dd:c25:c25:94de:1c5e/1282c19:dd:d9:dd:c25:c25:94de:1c5e
962c19:dd:d9:dd:c25:c25:94de:1c5f/1282c19:dd:d9:dd:c25:c25:94de:1c5f
972c19:dd:d9:dd:c25:c25:94de:1c60/1282c19:dd:d9:dd:c25:c25:94de:1c60
982c19:dd:d9:dd:c25:c25:94de:1c61/1282c19:dd:d9:dd:c25:c25:94de:1c61
992c19:dd:d9:dd:c25:c25:94de:1c62/1282c19:dd:d9:dd:c25:c25:94de:1c62
1002c19:dd:d9:dd:c25:c25:94de:1c63/1282c19:dd:d9:dd:c25:c25:94de:1c63
1012c19:dd:d9:dd:c25:c25:94de:1c64/1282c19:dd:d9:dd:c25:c25:94de:1c64
1022c19:dd:d9:dd:c25:c25:94de:1c65/1282c19:dd:d9:dd:c25:c25:94de:1c65
1032c19:dd:d9:dd:c25:c25:94de:1c66/1282c19:dd:d9:dd:c25:c25:94de:1c66
1042c19:dd:d9:dd:c25:c25:94de:1c67/1282c19:dd:d9:dd:c25:c25:94de:1c67
1052c19:dd:d9:dd:c25:c25:94de:1c68/1282c19:dd:d9:dd:c25:c25:94de:1c68
1062c19:dd:d9:dd:c25:c25:94de:1c69/1282c19:dd:d9:dd:c25:c25:94de:1c69
1072c19:dd:d9:dd:c25:c25:94de:1c6a/1282c19:dd:d9:dd:c25:c25:94de:1c6a
1082c19:dd:d9:dd:c25:c25:94de:1c6b/1282c19:dd:d9:dd:c25:c25:94de:1c6b
1092c19:dd:d9:dd:c25:c25:94de:1c6c/1282c19:dd:d9:dd:c25:c25:94de:1c6c
1102c19:dd:d9:dd:c25:c25:94de:1c6d/1282c19:dd:d9:dd:c25:c25:94de:1c6d
1112c19:dd:d9:dd:c25:c25:94de:1c6e/1282c19:dd:d9:dd:c25:c25:94de:1c6e
1122c19:dd:d9:dd:c25:c25:94de:1c6f/1282c19:dd:d9:dd:c25:c25:94de:1c6f
1132c19:dd:d9:dd:c25:c25:94de:1c70/1282c19:dd:d9:dd:c25:c25:94de:1c70
1142c19:dd:d9:dd:c25:c25:94de:1c71/1282c19:dd:d9:dd:c25:c25:94de:1c71
1152c19:dd:d9:dd:c25:c25:94de:1c72/1282c19:dd:d9:dd:c25:c25:94de:1c72
1162c19:dd:d9:dd:c25:c25:94de:1c73/1282c19:dd:d9:dd:c25:c25:94de:1c73
1172c19:dd:d9:dd:c25:c25:94de:1c74/1282c19:dd:d9:dd:c25:c25:94de:1c74
1182c19:dd:d9:dd:c25:c25:94de:1c75/1282c19:dd:d9:dd:c25:c25:94de:1c75
1192c19:dd:d9:dd:c25:c25:94de:1c76/1282c19:dd:d9:dd:c25:c25:94de:1c76
1202c19:dd:d9:dd:c25:c25:94de:1c77/1282c19:dd:d9:dd:c25:c25:94de:1c77
1212c19:dd:d9:dd:c25:c25:94de:1c78/1282c19:dd:d9:dd:c25:c25:94de:1c78
1222c19:dd:d9:dd:c25:c25:94de:1c79/1282c19:dd:d9:dd:c25:c25:94de:1c79
1232c19:dd:d9:dd:c25:c25:94de:1c7a/1282c19:dd:d9:dd:c25:c25:94de:1c7a
1242c19:dd:d9:dd:c25:c25:94de:1c7b/1282c19:dd:d9:dd:c25:c25:94de:1c7b
1252c19:dd:d9:dd:c25:c25:94de:1c7c/1282c19:dd:d9:dd:c25:c25:94de:1c7c
1262c19:dd:d9:dd:c25:c25:94de:1c7d/1282c19:dd:d9:dd:c25:c25:94de:1c7d
1272c19:dd:d9:dd:c25:c25:94de:1c7e/1282c19:dd:d9:dd:c25:c25:94de:1c7e
1282c19:dd:d9:dd:c25:c25:94de:1c7f/1282c19:dd:d9:dd:c25:c25:94de:1c7f
1292c19:dd:d9:dd:c25:c25:94de:1c80/1282c19:dd:d9:dd:c25:c25:94de:1c80
1302c19:dd:d9:dd:c25:c25:94de:1c81/1282c19:dd:d9:dd:c25:c25:94de:1c81
1312c19:dd:d9:dd:c25:c25:94de:1c82/1282c19:dd:d9:dd:c25:c25:94de:1c82
1322c19:dd:d9:dd:c25:c25:94de:1c83/1282c19:dd:d9:dd:c25:c25:94de:1c83
1332c19:dd:d9:dd:c25:c25:94de:1c84/1282c19:dd:d9:dd:c25:c25:94de:1c84
1342c19:dd:d9:dd:c25:c25:94de:1c85/1282c19:dd:d9:dd:c25:c25:94de:1c85
1352c19:dd:d9:dd:c25:c25:94de:1c86/1282c19:dd:d9:dd:c25:c25:94de:1c86
1362c19:dd:d9:dd:c25:c25:94de:1c87/1282c19:dd:d9:dd:c25:c25:94de:1c87
1372c19:dd:d9:dd:c25:c25:94de:1c88/1282c19:dd:d9:dd:c25:c25:94de:1c88
1382c19:dd:d9:dd:c25:c25:94de:1c89/1282c19:dd:d9:dd:c25:c25:94de:1c89
1392c19:dd:d9:dd:c25:c25:94de:1c8a/1282c19:dd:d9:dd:c25:c25:94de:1c8a
1402c19:dd:d9:dd:c25:c25:94de:1c8b/1282c19:dd:d9:dd:c25:c25:94de:1c8b
1412c19:dd:d9:dd:c25:c25:94de:1c8c/1282c19:dd:d9:dd:c25:c25:94de:1c8c
1422c19:dd:d9:dd:c25:c25:94de:1c8d/1282c19:dd:d9:dd:c25:c25:94de:1c8d
1432c19:dd:d9:dd:c25:c25:94de:1c8e/1282c19:dd:d9:dd:c25:c25:94de:1c8e
1442c19:dd:d9:dd:c25:c25:94de:1c8f/1282c19:dd:d9:dd:c25:c25:94de:1c8f
1452c19:dd:d9:dd:c25:c25:94de:1c90/1282c19:dd:d9:dd:c25:c25:94de:1c90
1462c19:dd:d9:dd:c25:c25:94de:1c91/1282c19:dd:d9:dd:c25:c25:94de:1c91
1472c19:dd:d9:dd:c25:c25:94de:1c92/1282c19:dd:d9:dd:c25:c25:94de:1c92
1482c19:dd:d9:dd:c25:c25:94de:1c93/1282c19:dd:d9:dd:c25:c25:94de:1c93
1492c19:dd:d9:dd:c25:c25:94de:1c94/1282c19:dd:d9:dd:c25:c25:94de:1c94
1502c19:dd:d9:dd:c25:c25:94de:1c95/1282c19:dd:d9:dd:c25:c25:94de:1c95
1512c19:dd:d9:dd:c25:c25:94de:1c96/1282c19:dd:d9:dd:c25:c25:94de:1c96
1522c19:dd:d9:dd:c25:c25:94de:1c97/1282c19:dd:d9:dd:c25:c25:94de:1c97
1532c19:dd:d9:dd:c25:c25:94de:1c98/1282c19:dd:d9:dd:c25:c25:94de:1c98
1542c19:dd:d9:dd:c25:c25:94de:1c99/1282c19:dd:d9:dd:c25:c25:94de:1c99
1552c19:dd:d9:dd:c25:c25:94de:1c9a/1282c19:dd:d9:dd:c25:c25:94de:1c9a
1562c19:dd:d9:dd:c25:c25:94de:1c9b/1282c19:dd:d9:dd:c25:c25:94de:1c9b
1572c19:dd:d9:dd:c25:c25:94de:1c9c/1282c19:dd:d9:dd:c25:c25:94de:1c9c
1582c19:dd:d9:dd:c25:c25:94de:1c9d/1282c19:dd:d9:dd:c25:c25:94de:1c9d
1592c19:dd:d9:dd:c25:c25:94de:1c9e/1282c19:dd:d9:dd:c25:c25:94de:1c9e
1602c19:dd:d9:dd:c25:c25:94de:1c9f/1282c19:dd:d9:dd:c25:c25:94de:1c9f
1612c19:dd:d9:dd:c25:c25:94de:1ca0/1282c19:dd:d9:dd:c25:c25:94de:1ca0
1622c19:dd:d9:dd:c25:c25:94de:1ca1/1282c19:dd:d9:dd:c25:c25:94de:1ca1
1632c19:dd:d9:dd:c25:c25:94de:1ca2/1282c19:dd:d9:dd:c25:c25:94de:1ca2
1642c19:dd:d9:dd:c25:c25:94de:1ca3/1282c19:dd:d9:dd:c25:c25:94de:1ca3
1652c19:dd:d9:dd:c25:c25:94de:1ca4/1282c19:dd:d9:dd:c25:c25:94de:1ca4
1662c19:dd:d9:dd:c25:c25:94de:1ca5/1282c19:dd:d9:dd:c25:c25:94de:1ca5
1672c19:dd:d9:dd:c25:c25:94de:1ca6/1282c19:dd:d9:dd:c25:c25:94de:1ca6
1682c19:dd:d9:dd:c25:c25:94de:1ca7/1282c19:dd:d9:dd:c25:c25:94de:1ca7
1692c19:dd:d9:dd:c25:c25:94de:1ca8/1282c19:dd:d9:dd:c25:c25:94de:1ca8
1702c19:dd:d9:dd:c25:c25:94de:1ca9/1282c19:dd:d9:dd:c25:c25:94de:1ca9
1712c19:dd:d9:dd:c25:c25:94de:1caa/1282c19:dd:d9:dd:c25:c25:94de:1caa
1722c19:dd:d9:dd:c25:c25:94de:1cab/1282c19:dd:d9:dd:c25:c25:94de:1cab
1732c19:dd:d9:dd:c25:c25:94de:1cac/1282c19:dd:d9:dd:c25:c25:94de:1cac
1742c19:dd:d9:dd:c25:c25:94de:1cad/1282c19:dd:d9:dd:c25:c25:94de:1cad
1752c19:dd:d9:dd:c25:c25:94de:1cae/1282c19:dd:d9:dd:c25:c25:94de:1cae
1762c19:dd:d9:dd:c25:c25:94de:1caf/1282c19:dd:d9:dd:c25:c25:94de:1caf
1772c19:dd:d9:dd:c25:c25:94de:1cb0/1282c19:dd:d9:dd:c25:c25:94de:1cb0
1782c19:dd:d9:dd:c25:c25:94de:1cb1/1282c19:dd:d9:dd:c25:c25:94de:1cb1
1792c19:dd:d9:dd:c25:c25:94de:1cb2/1282c19:dd:d9:dd:c25:c25:94de:1cb2
1802c19:dd:d9:dd:c25:c25:94de:1cb3/1282c19:dd:d9:dd:c25:c25:94de:1cb3
1812c19:dd:d9:dd:c25:c25:94de:1cb4/1282c19:dd:d9:dd:c25:c25:94de:1cb4
1822c19:dd:d9:dd:c25:c25:94de:1cb5/1282c19:dd:d9:dd:c25:c25:94de:1cb5
1832c19:dd:d9:dd:c25:c25:94de:1cb6/1282c19:dd:d9:dd:c25:c25:94de:1cb6
1842c19:dd:d9:dd:c25:c25:94de:1cb7/1282c19:dd:d9:dd:c25:c25:94de:1cb7
1852c19:dd:d9:dd:c25:c25:94de:1cb8/1282c19:dd:d9:dd:c25:c25:94de:1cb8
1862c19:dd:d9:dd:c25:c25:94de:1cb9/1282c19:dd:d9:dd:c25:c25:94de:1cb9
1872c19:dd:d9:dd:c25:c25:94de:1cba/1282c19:dd:d9:dd:c25:c25:94de:1cba
1882c19:dd:d9:dd:c25:c25:94de:1cbb/1282c19:dd:d9:dd:c25:c25:94de:1cbb
1892c19:dd:d9:dd:c25:c25:94de:1cbc/1282c19:dd:d9:dd:c25:c25:94de:1cbc
1902c19:dd:d9:dd:c25:c25:94de:1cbd/1282c19:dd:d9:dd:c25:c25:94de:1cbd
1912c19:dd:d9:dd:c25:c25:94de:1cbe/1282c19:dd:d9:dd:c25:c25:94de:1cbe
1922c19:dd:d9:dd:c25:c25:94de:1cbf/1282c19:dd:d9:dd:c25:c25:94de:1cbf
1932c19:dd:d9:dd:c25:c25:94de:1cc0/1282c19:dd:d9:dd:c25:c25:94de:1cc0
1942c19:dd:d9:dd:c25:c25:94de:1cc1/1282c19:dd:d9:dd:c25:c25:94de:1cc1
1952c19:dd:d9:dd:c25:c25:94de:1cc2/1282c19:dd:d9:dd:c25:c25:94de:1cc2
1962c19:dd:d9:dd:c25:c25:94de:1cc3/1282c19:dd:d9:dd:c25:c25:94de:1cc3
1972c19:dd:d9:dd:c25:c25:94de:1cc4/1282c19:dd:d9:dd:c25:c25:94de:1cc4
1982c19:dd:d9:dd:c25:c25:94de:1cc5/1282c19:dd:d9:dd:c25:c25:94de:1cc5
1992c19:dd:d9:dd:c25:c25:94de:1cc6/1282c19:dd:d9:dd:c25:c25:94de:1cc6
2002c19:dd:d9:dd:c25:c25:94de:1cc7/1282c19:dd:d9:dd:c25:c25:94de:1cc7
2012c19:dd:d9:dd:c25:c25:94de:1cc8/1282c19:dd:d9:dd:c25:c25:94de:1cc8
2022c19:dd:d9:dd:c25:c25:94de:1cc9/1282c19:dd:d9:dd:c25:c25:94de:1cc9
2032c19:dd:d9:dd:c25:c25:94de:1cca/1282c19:dd:d9:dd:c25:c25:94de:1cca
2042c19:dd:d9:dd:c25:c25:94de:1ccb/1282c19:dd:d9:dd:c25:c25:94de:1ccb
2052c19:dd:d9:dd:c25:c25:94de:1ccc/1282c19:dd:d9:dd:c25:c25:94de:1ccc
2062c19:dd:d9:dd:c25:c25:94de:1ccd/1282c19:dd:d9:dd:c25:c25:94de:1ccd
2072c19:dd:d9:dd:c25:c25:94de:1cce/1282c19:dd:d9:dd:c25:c25:94de:1cce
2082c19:dd:d9:dd:c25:c25:94de:1ccf/1282c19:dd:d9:dd:c25:c25:94de:1ccf
2092c19:dd:d9:dd:c25:c25:94de:1cd0/1282c19:dd:d9:dd:c25:c25:94de:1cd0
2102c19:dd:d9:dd:c25:c25:94de:1cd1/1282c19:dd:d9:dd:c25:c25:94de:1cd1
2112c19:dd:d9:dd:c25:c25:94de:1cd2/1282c19:dd:d9:dd:c25:c25:94de:1cd2
2122c19:dd:d9:dd:c25:c25:94de:1cd3/1282c19:dd:d9:dd:c25:c25:94de:1cd3
2132c19:dd:d9:dd:c25:c25:94de:1cd4/1282c19:dd:d9:dd:c25:c25:94de:1cd4
2142c19:dd:d9:dd:c25:c25:94de:1cd5/1282c19:dd:d9:dd:c25:c25:94de:1cd5
2152c19:dd:d9:dd:c25:c25:94de:1cd6/1282c19:dd:d9:dd:c25:c25:94de:1cd6
2162c19:dd:d9:dd:c25:c25:94de:1cd7/1282c19:dd:d9:dd:c25:c25:94de:1cd7
2172c19:dd:d9:dd:c25:c25:94de:1cd8/1282c19:dd:d9:dd:c25:c25:94de:1cd8
2182c19:dd:d9:dd:c25:c25:94de:1cd9/1282c19:dd:d9:dd:c25:c25:94de:1cd9
2192c19:dd:d9:dd:c25:c25:94de:1cda/1282c19:dd:d9:dd:c25:c25:94de:1cda
2202c19:dd:d9:dd:c25:c25:94de:1cdb/1282c19:dd:d9:dd:c25:c25:94de:1cdb
2212c19:dd:d9:dd:c25:c25:94de:1cdc/1282c19:dd:d9:dd:c25:c25:94de:1cdc
2222c19:dd:d9:dd:c25:c25:94de:1cdd/1282c19:dd:d9:dd:c25:c25:94de:1cdd
2232c19:dd:d9:dd:c25:c25:94de:1cde/1282c19:dd:d9:dd:c25:c25:94de:1cde
2242c19:dd:d9:dd:c25:c25:94de:1cdf/1282c19:dd:d9:dd:c25:c25:94de:1cdf
2252c19:dd:d9:dd:c25:c25:94de:1ce0/1282c19:dd:d9:dd:c25:c25:94de:1ce0
2262c19:dd:d9:dd:c25:c25:94de:1ce1/1282c19:dd:d9:dd:c25:c25:94de:1ce1
2272c19:dd:d9:dd:c25:c25:94de:1ce2/1282c19:dd:d9:dd:c25:c25:94de:1ce2
2282c19:dd:d9:dd:c25:c25:94de:1ce3/1282c19:dd:d9:dd:c25:c25:94de:1ce3
2292c19:dd:d9:dd:c25:c25:94de:1ce4/1282c19:dd:d9:dd:c25:c25:94de:1ce4
2302c19:dd:d9:dd:c25:c25:94de:1ce5/1282c19:dd:d9:dd:c25:c25:94de:1ce5
2312c19:dd:d9:dd:c25:c25:94de:1ce6/1282c19:dd:d9:dd:c25:c25:94de:1ce6
2322c19:dd:d9:dd:c25:c25:94de:1ce7/1282c19:dd:d9:dd:c25:c25:94de:1ce7
2332c19:dd:d9:dd:c25:c25:94de:1ce8/1282c19:dd:d9:dd:c25:c25:94de:1ce8
2342c19:dd:d9:dd:c25:c25:94de:1ce9/1282c19:dd:d9:dd:c25:c25:94de:1ce9
2352c19:dd:d9:dd:c25:c25:94de:1cea/1282c19:dd:d9:dd:c25:c25:94de:1cea
2362c19:dd:d9:dd:c25:c25:94de:1ceb/1282c19:dd:d9:dd:c25:c25:94de:1ceb
2372c19:dd:d9:dd:c25:c25:94de:1cec/1282c19:dd:d9:dd:c25:c25:94de:1cec
2382c19:dd:d9:dd:c25:c25:94de:1ced/1282c19:dd:d9:dd:c25:c25:94de:1ced
2392c19:dd:d9:dd:c25:c25:94de:1cee/1282c19:dd:d9:dd:c25:c25:94de:1cee
2402c19:dd:d9:dd:c25:c25:94de:1cef/1282c19:dd:d9:dd:c25:c25:94de:1cef
2412c19:dd:d9:dd:c25:c25:94de:1cf0/1282c19:dd:d9:dd:c25:c25:94de:1cf0
2422c19:dd:d9:dd:c25:c25:94de:1cf1/1282c19:dd:d9:dd:c25:c25:94de:1cf1
2432c19:dd:d9:dd:c25:c25:94de:1cf2/1282c19:dd:d9:dd:c25:c25:94de:1cf2
2442c19:dd:d9:dd:c25:c25:94de:1cf3/1282c19:dd:d9:dd:c25:c25:94de:1cf3
2452c19:dd:d9:dd:c25:c25:94de:1cf4/1282c19:dd:d9:dd:c25:c25:94de:1cf4
2462c19:dd:d9:dd:c25:c25:94de:1cf5/1282c19:dd:d9:dd:c25:c25:94de:1cf5
2472c19:dd:d9:dd:c25:c25:94de:1cf6/1282c19:dd:d9:dd:c25:c25:94de:1cf6
2482c19:dd:d9:dd:c25:c25:94de:1cf7/1282c19:dd:d9:dd:c25:c25:94de:1cf7
2492c19:dd:d9:dd:c25:c25:94de:1cf8/1282c19:dd:d9:dd:c25:c25:94de:1cf8
2502c19:dd:d9:dd:c25:c25:94de:1cf9/1282c19:dd:d9:dd:c25:c25:94de:1cf9
2512c19:dd:d9:dd:c25:c25:94de:1cfa/1282c19:dd:d9:dd:c25:c25:94de:1cfa
2522c19:dd:d9:dd:c25:c25:94de:1cfb/1282c19:dd:d9:dd:c25:c25:94de:1cfb
2532c19:dd:d9:dd:c25:c25:94de:1cfc/1282c19:dd:d9:dd:c25:c25:94de:1cfc
2542c19:dd:d9:dd:c25:c25:94de:1cfd/1282c19:dd:d9:dd:c25:c25:94de:1cfd
2552c19:dd:d9:dd:c25:c25:94de:1cfe/1282c19:dd:d9:dd:c25:c25:94de:1cfe
2562c19:dd:d9:dd:c25:c25:94de:1cff/1282c19:dd:d9:dd:c25:c25:94de:1cff

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.