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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:d915:8a00/120
First address
2c19:dd:d9:dd:c25:c25:d915:8a00
Last address
2c19:dd:d9:dd:c25:c25:d915:8aff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:8a00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
a.8.5.1.9.d.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:d915:8a00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:8a00/1282c19:dd:d9:dd:c25:c25:d915:8a00
22c19:dd:d9:dd:c25:c25:d915:8a01/1282c19:dd:d9:dd:c25:c25:d915:8a01
32c19:dd:d9:dd:c25:c25:d915:8a02/1282c19:dd:d9:dd:c25:c25:d915:8a02
42c19:dd:d9:dd:c25:c25:d915:8a03/1282c19:dd:d9:dd:c25:c25:d915:8a03
52c19:dd:d9:dd:c25:c25:d915:8a04/1282c19:dd:d9:dd:c25:c25:d915:8a04
62c19:dd:d9:dd:c25:c25:d915:8a05/1282c19:dd:d9:dd:c25:c25:d915:8a05
72c19:dd:d9:dd:c25:c25:d915:8a06/1282c19:dd:d9:dd:c25:c25:d915:8a06
82c19:dd:d9:dd:c25:c25:d915:8a07/1282c19:dd:d9:dd:c25:c25:d915:8a07
92c19:dd:d9:dd:c25:c25:d915:8a08/1282c19:dd:d9:dd:c25:c25:d915:8a08
102c19:dd:d9:dd:c25:c25:d915:8a09/1282c19:dd:d9:dd:c25:c25:d915:8a09
112c19:dd:d9:dd:c25:c25:d915:8a0a/1282c19:dd:d9:dd:c25:c25:d915:8a0a
122c19:dd:d9:dd:c25:c25:d915:8a0b/1282c19:dd:d9:dd:c25:c25:d915:8a0b
132c19:dd:d9:dd:c25:c25:d915:8a0c/1282c19:dd:d9:dd:c25:c25:d915:8a0c
142c19:dd:d9:dd:c25:c25:d915:8a0d/1282c19:dd:d9:dd:c25:c25:d915:8a0d
152c19:dd:d9:dd:c25:c25:d915:8a0e/1282c19:dd:d9:dd:c25:c25:d915:8a0e
162c19:dd:d9:dd:c25:c25:d915:8a0f/1282c19:dd:d9:dd:c25:c25:d915:8a0f
172c19:dd:d9:dd:c25:c25:d915:8a10/1282c19:dd:d9:dd:c25:c25:d915:8a10
182c19:dd:d9:dd:c25:c25:d915:8a11/1282c19:dd:d9:dd:c25:c25:d915:8a11
192c19:dd:d9:dd:c25:c25:d915:8a12/1282c19:dd:d9:dd:c25:c25:d915:8a12
202c19:dd:d9:dd:c25:c25:d915:8a13/1282c19:dd:d9:dd:c25:c25:d915:8a13
212c19:dd:d9:dd:c25:c25:d915:8a14/1282c19:dd:d9:dd:c25:c25:d915:8a14
222c19:dd:d9:dd:c25:c25:d915:8a15/1282c19:dd:d9:dd:c25:c25:d915:8a15
232c19:dd:d9:dd:c25:c25:d915:8a16/1282c19:dd:d9:dd:c25:c25:d915:8a16
242c19:dd:d9:dd:c25:c25:d915:8a17/1282c19:dd:d9:dd:c25:c25:d915:8a17
252c19:dd:d9:dd:c25:c25:d915:8a18/1282c19:dd:d9:dd:c25:c25:d915:8a18
262c19:dd:d9:dd:c25:c25:d915:8a19/1282c19:dd:d9:dd:c25:c25:d915:8a19
272c19:dd:d9:dd:c25:c25:d915:8a1a/1282c19:dd:d9:dd:c25:c25:d915:8a1a
282c19:dd:d9:dd:c25:c25:d915:8a1b/1282c19:dd:d9:dd:c25:c25:d915:8a1b
292c19:dd:d9:dd:c25:c25:d915:8a1c/1282c19:dd:d9:dd:c25:c25:d915:8a1c
302c19:dd:d9:dd:c25:c25:d915:8a1d/1282c19:dd:d9:dd:c25:c25:d915:8a1d
312c19:dd:d9:dd:c25:c25:d915:8a1e/1282c19:dd:d9:dd:c25:c25:d915:8a1e
322c19:dd:d9:dd:c25:c25:d915:8a1f/1282c19:dd:d9:dd:c25:c25:d915:8a1f
332c19:dd:d9:dd:c25:c25:d915:8a20/1282c19:dd:d9:dd:c25:c25:d915:8a20
342c19:dd:d9:dd:c25:c25:d915:8a21/1282c19:dd:d9:dd:c25:c25:d915:8a21
352c19:dd:d9:dd:c25:c25:d915:8a22/1282c19:dd:d9:dd:c25:c25:d915:8a22
362c19:dd:d9:dd:c25:c25:d915:8a23/1282c19:dd:d9:dd:c25:c25:d915:8a23
372c19:dd:d9:dd:c25:c25:d915:8a24/1282c19:dd:d9:dd:c25:c25:d915:8a24
382c19:dd:d9:dd:c25:c25:d915:8a25/1282c19:dd:d9:dd:c25:c25:d915:8a25
392c19:dd:d9:dd:c25:c25:d915:8a26/1282c19:dd:d9:dd:c25:c25:d915:8a26
402c19:dd:d9:dd:c25:c25:d915:8a27/1282c19:dd:d9:dd:c25:c25:d915:8a27
412c19:dd:d9:dd:c25:c25:d915:8a28/1282c19:dd:d9:dd:c25:c25:d915:8a28
422c19:dd:d9:dd:c25:c25:d915:8a29/1282c19:dd:d9:dd:c25:c25:d915:8a29
432c19:dd:d9:dd:c25:c25:d915:8a2a/1282c19:dd:d9:dd:c25:c25:d915:8a2a
442c19:dd:d9:dd:c25:c25:d915:8a2b/1282c19:dd:d9:dd:c25:c25:d915:8a2b
452c19:dd:d9:dd:c25:c25:d915:8a2c/1282c19:dd:d9:dd:c25:c25:d915:8a2c
462c19:dd:d9:dd:c25:c25:d915:8a2d/1282c19:dd:d9:dd:c25:c25:d915:8a2d
472c19:dd:d9:dd:c25:c25:d915:8a2e/1282c19:dd:d9:dd:c25:c25:d915:8a2e
482c19:dd:d9:dd:c25:c25:d915:8a2f/1282c19:dd:d9:dd:c25:c25:d915:8a2f
492c19:dd:d9:dd:c25:c25:d915:8a30/1282c19:dd:d9:dd:c25:c25:d915:8a30
502c19:dd:d9:dd:c25:c25:d915:8a31/1282c19:dd:d9:dd:c25:c25:d915:8a31
512c19:dd:d9:dd:c25:c25:d915:8a32/1282c19:dd:d9:dd:c25:c25:d915:8a32
522c19:dd:d9:dd:c25:c25:d915:8a33/1282c19:dd:d9:dd:c25:c25:d915:8a33
532c19:dd:d9:dd:c25:c25:d915:8a34/1282c19:dd:d9:dd:c25:c25:d915:8a34
542c19:dd:d9:dd:c25:c25:d915:8a35/1282c19:dd:d9:dd:c25:c25:d915:8a35
552c19:dd:d9:dd:c25:c25:d915:8a36/1282c19:dd:d9:dd:c25:c25:d915:8a36
562c19:dd:d9:dd:c25:c25:d915:8a37/1282c19:dd:d9:dd:c25:c25:d915:8a37
572c19:dd:d9:dd:c25:c25:d915:8a38/1282c19:dd:d9:dd:c25:c25:d915:8a38
582c19:dd:d9:dd:c25:c25:d915:8a39/1282c19:dd:d9:dd:c25:c25:d915:8a39
592c19:dd:d9:dd:c25:c25:d915:8a3a/1282c19:dd:d9:dd:c25:c25:d915:8a3a
602c19:dd:d9:dd:c25:c25:d915:8a3b/1282c19:dd:d9:dd:c25:c25:d915:8a3b
612c19:dd:d9:dd:c25:c25:d915:8a3c/1282c19:dd:d9:dd:c25:c25:d915:8a3c
622c19:dd:d9:dd:c25:c25:d915:8a3d/1282c19:dd:d9:dd:c25:c25:d915:8a3d
632c19:dd:d9:dd:c25:c25:d915:8a3e/1282c19:dd:d9:dd:c25:c25:d915:8a3e
642c19:dd:d9:dd:c25:c25:d915:8a3f/1282c19:dd:d9:dd:c25:c25:d915:8a3f
652c19:dd:d9:dd:c25:c25:d915:8a40/1282c19:dd:d9:dd:c25:c25:d915:8a40
662c19:dd:d9:dd:c25:c25:d915:8a41/1282c19:dd:d9:dd:c25:c25:d915:8a41
672c19:dd:d9:dd:c25:c25:d915:8a42/1282c19:dd:d9:dd:c25:c25:d915:8a42
682c19:dd:d9:dd:c25:c25:d915:8a43/1282c19:dd:d9:dd:c25:c25:d915:8a43
692c19:dd:d9:dd:c25:c25:d915:8a44/1282c19:dd:d9:dd:c25:c25:d915:8a44
702c19:dd:d9:dd:c25:c25:d915:8a45/1282c19:dd:d9:dd:c25:c25:d915:8a45
712c19:dd:d9:dd:c25:c25:d915:8a46/1282c19:dd:d9:dd:c25:c25:d915:8a46
722c19:dd:d9:dd:c25:c25:d915:8a47/1282c19:dd:d9:dd:c25:c25:d915:8a47
732c19:dd:d9:dd:c25:c25:d915:8a48/1282c19:dd:d9:dd:c25:c25:d915:8a48
742c19:dd:d9:dd:c25:c25:d915:8a49/1282c19:dd:d9:dd:c25:c25:d915:8a49
752c19:dd:d9:dd:c25:c25:d915:8a4a/1282c19:dd:d9:dd:c25:c25:d915:8a4a
762c19:dd:d9:dd:c25:c25:d915:8a4b/1282c19:dd:d9:dd:c25:c25:d915:8a4b
772c19:dd:d9:dd:c25:c25:d915:8a4c/1282c19:dd:d9:dd:c25:c25:d915:8a4c
782c19:dd:d9:dd:c25:c25:d915:8a4d/1282c19:dd:d9:dd:c25:c25:d915:8a4d
792c19:dd:d9:dd:c25:c25:d915:8a4e/1282c19:dd:d9:dd:c25:c25:d915:8a4e
802c19:dd:d9:dd:c25:c25:d915:8a4f/1282c19:dd:d9:dd:c25:c25:d915:8a4f
812c19:dd:d9:dd:c25:c25:d915:8a50/1282c19:dd:d9:dd:c25:c25:d915:8a50
822c19:dd:d9:dd:c25:c25:d915:8a51/1282c19:dd:d9:dd:c25:c25:d915:8a51
832c19:dd:d9:dd:c25:c25:d915:8a52/1282c19:dd:d9:dd:c25:c25:d915:8a52
842c19:dd:d9:dd:c25:c25:d915:8a53/1282c19:dd:d9:dd:c25:c25:d915:8a53
852c19:dd:d9:dd:c25:c25:d915:8a54/1282c19:dd:d9:dd:c25:c25:d915:8a54
862c19:dd:d9:dd:c25:c25:d915:8a55/1282c19:dd:d9:dd:c25:c25:d915:8a55
872c19:dd:d9:dd:c25:c25:d915:8a56/1282c19:dd:d9:dd:c25:c25:d915:8a56
882c19:dd:d9:dd:c25:c25:d915:8a57/1282c19:dd:d9:dd:c25:c25:d915:8a57
892c19:dd:d9:dd:c25:c25:d915:8a58/1282c19:dd:d9:dd:c25:c25:d915:8a58
902c19:dd:d9:dd:c25:c25:d915:8a59/1282c19:dd:d9:dd:c25:c25:d915:8a59
912c19:dd:d9:dd:c25:c25:d915:8a5a/1282c19:dd:d9:dd:c25:c25:d915:8a5a
922c19:dd:d9:dd:c25:c25:d915:8a5b/1282c19:dd:d9:dd:c25:c25:d915:8a5b
932c19:dd:d9:dd:c25:c25:d915:8a5c/1282c19:dd:d9:dd:c25:c25:d915:8a5c
942c19:dd:d9:dd:c25:c25:d915:8a5d/1282c19:dd:d9:dd:c25:c25:d915:8a5d
952c19:dd:d9:dd:c25:c25:d915:8a5e/1282c19:dd:d9:dd:c25:c25:d915:8a5e
962c19:dd:d9:dd:c25:c25:d915:8a5f/1282c19:dd:d9:dd:c25:c25:d915:8a5f
972c19:dd:d9:dd:c25:c25:d915:8a60/1282c19:dd:d9:dd:c25:c25:d915:8a60
982c19:dd:d9:dd:c25:c25:d915:8a61/1282c19:dd:d9:dd:c25:c25:d915:8a61
992c19:dd:d9:dd:c25:c25:d915:8a62/1282c19:dd:d9:dd:c25:c25:d915:8a62
1002c19:dd:d9:dd:c25:c25:d915:8a63/1282c19:dd:d9:dd:c25:c25:d915:8a63
1012c19:dd:d9:dd:c25:c25:d915:8a64/1282c19:dd:d9:dd:c25:c25:d915:8a64
1022c19:dd:d9:dd:c25:c25:d915:8a65/1282c19:dd:d9:dd:c25:c25:d915:8a65
1032c19:dd:d9:dd:c25:c25:d915:8a66/1282c19:dd:d9:dd:c25:c25:d915:8a66
1042c19:dd:d9:dd:c25:c25:d915:8a67/1282c19:dd:d9:dd:c25:c25:d915:8a67
1052c19:dd:d9:dd:c25:c25:d915:8a68/1282c19:dd:d9:dd:c25:c25:d915:8a68
1062c19:dd:d9:dd:c25:c25:d915:8a69/1282c19:dd:d9:dd:c25:c25:d915:8a69
1072c19:dd:d9:dd:c25:c25:d915:8a6a/1282c19:dd:d9:dd:c25:c25:d915:8a6a
1082c19:dd:d9:dd:c25:c25:d915:8a6b/1282c19:dd:d9:dd:c25:c25:d915:8a6b
1092c19:dd:d9:dd:c25:c25:d915:8a6c/1282c19:dd:d9:dd:c25:c25:d915:8a6c
1102c19:dd:d9:dd:c25:c25:d915:8a6d/1282c19:dd:d9:dd:c25:c25:d915:8a6d
1112c19:dd:d9:dd:c25:c25:d915:8a6e/1282c19:dd:d9:dd:c25:c25:d915:8a6e
1122c19:dd:d9:dd:c25:c25:d915:8a6f/1282c19:dd:d9:dd:c25:c25:d915:8a6f
1132c19:dd:d9:dd:c25:c25:d915:8a70/1282c19:dd:d9:dd:c25:c25:d915:8a70
1142c19:dd:d9:dd:c25:c25:d915:8a71/1282c19:dd:d9:dd:c25:c25:d915:8a71
1152c19:dd:d9:dd:c25:c25:d915:8a72/1282c19:dd:d9:dd:c25:c25:d915:8a72
1162c19:dd:d9:dd:c25:c25:d915:8a73/1282c19:dd:d9:dd:c25:c25:d915:8a73
1172c19:dd:d9:dd:c25:c25:d915:8a74/1282c19:dd:d9:dd:c25:c25:d915:8a74
1182c19:dd:d9:dd:c25:c25:d915:8a75/1282c19:dd:d9:dd:c25:c25:d915:8a75
1192c19:dd:d9:dd:c25:c25:d915:8a76/1282c19:dd:d9:dd:c25:c25:d915:8a76
1202c19:dd:d9:dd:c25:c25:d915:8a77/1282c19:dd:d9:dd:c25:c25:d915:8a77
1212c19:dd:d9:dd:c25:c25:d915:8a78/1282c19:dd:d9:dd:c25:c25:d915:8a78
1222c19:dd:d9:dd:c25:c25:d915:8a79/1282c19:dd:d9:dd:c25:c25:d915:8a79
1232c19:dd:d9:dd:c25:c25:d915:8a7a/1282c19:dd:d9:dd:c25:c25:d915:8a7a
1242c19:dd:d9:dd:c25:c25:d915:8a7b/1282c19:dd:d9:dd:c25:c25:d915:8a7b
1252c19:dd:d9:dd:c25:c25:d915:8a7c/1282c19:dd:d9:dd:c25:c25:d915:8a7c
1262c19:dd:d9:dd:c25:c25:d915:8a7d/1282c19:dd:d9:dd:c25:c25:d915:8a7d
1272c19:dd:d9:dd:c25:c25:d915:8a7e/1282c19:dd:d9:dd:c25:c25:d915:8a7e
1282c19:dd:d9:dd:c25:c25:d915:8a7f/1282c19:dd:d9:dd:c25:c25:d915:8a7f
1292c19:dd:d9:dd:c25:c25:d915:8a80/1282c19:dd:d9:dd:c25:c25:d915:8a80
1302c19:dd:d9:dd:c25:c25:d915:8a81/1282c19:dd:d9:dd:c25:c25:d915:8a81
1312c19:dd:d9:dd:c25:c25:d915:8a82/1282c19:dd:d9:dd:c25:c25:d915:8a82
1322c19:dd:d9:dd:c25:c25:d915:8a83/1282c19:dd:d9:dd:c25:c25:d915:8a83
1332c19:dd:d9:dd:c25:c25:d915:8a84/1282c19:dd:d9:dd:c25:c25:d915:8a84
1342c19:dd:d9:dd:c25:c25:d915:8a85/1282c19:dd:d9:dd:c25:c25:d915:8a85
1352c19:dd:d9:dd:c25:c25:d915:8a86/1282c19:dd:d9:dd:c25:c25:d915:8a86
1362c19:dd:d9:dd:c25:c25:d915:8a87/1282c19:dd:d9:dd:c25:c25:d915:8a87
1372c19:dd:d9:dd:c25:c25:d915:8a88/1282c19:dd:d9:dd:c25:c25:d915:8a88
1382c19:dd:d9:dd:c25:c25:d915:8a89/1282c19:dd:d9:dd:c25:c25:d915:8a89
1392c19:dd:d9:dd:c25:c25:d915:8a8a/1282c19:dd:d9:dd:c25:c25:d915:8a8a
1402c19:dd:d9:dd:c25:c25:d915:8a8b/1282c19:dd:d9:dd:c25:c25:d915:8a8b
1412c19:dd:d9:dd:c25:c25:d915:8a8c/1282c19:dd:d9:dd:c25:c25:d915:8a8c
1422c19:dd:d9:dd:c25:c25:d915:8a8d/1282c19:dd:d9:dd:c25:c25:d915:8a8d
1432c19:dd:d9:dd:c25:c25:d915:8a8e/1282c19:dd:d9:dd:c25:c25:d915:8a8e
1442c19:dd:d9:dd:c25:c25:d915:8a8f/1282c19:dd:d9:dd:c25:c25:d915:8a8f
1452c19:dd:d9:dd:c25:c25:d915:8a90/1282c19:dd:d9:dd:c25:c25:d915:8a90
1462c19:dd:d9:dd:c25:c25:d915:8a91/1282c19:dd:d9:dd:c25:c25:d915:8a91
1472c19:dd:d9:dd:c25:c25:d915:8a92/1282c19:dd:d9:dd:c25:c25:d915:8a92
1482c19:dd:d9:dd:c25:c25:d915:8a93/1282c19:dd:d9:dd:c25:c25:d915:8a93
1492c19:dd:d9:dd:c25:c25:d915:8a94/1282c19:dd:d9:dd:c25:c25:d915:8a94
1502c19:dd:d9:dd:c25:c25:d915:8a95/1282c19:dd:d9:dd:c25:c25:d915:8a95
1512c19:dd:d9:dd:c25:c25:d915:8a96/1282c19:dd:d9:dd:c25:c25:d915:8a96
1522c19:dd:d9:dd:c25:c25:d915:8a97/1282c19:dd:d9:dd:c25:c25:d915:8a97
1532c19:dd:d9:dd:c25:c25:d915:8a98/1282c19:dd:d9:dd:c25:c25:d915:8a98
1542c19:dd:d9:dd:c25:c25:d915:8a99/1282c19:dd:d9:dd:c25:c25:d915:8a99
1552c19:dd:d9:dd:c25:c25:d915:8a9a/1282c19:dd:d9:dd:c25:c25:d915:8a9a
1562c19:dd:d9:dd:c25:c25:d915:8a9b/1282c19:dd:d9:dd:c25:c25:d915:8a9b
1572c19:dd:d9:dd:c25:c25:d915:8a9c/1282c19:dd:d9:dd:c25:c25:d915:8a9c
1582c19:dd:d9:dd:c25:c25:d915:8a9d/1282c19:dd:d9:dd:c25:c25:d915:8a9d
1592c19:dd:d9:dd:c25:c25:d915:8a9e/1282c19:dd:d9:dd:c25:c25:d915:8a9e
1602c19:dd:d9:dd:c25:c25:d915:8a9f/1282c19:dd:d9:dd:c25:c25:d915:8a9f
1612c19:dd:d9:dd:c25:c25:d915:8aa0/1282c19:dd:d9:dd:c25:c25:d915:8aa0
1622c19:dd:d9:dd:c25:c25:d915:8aa1/1282c19:dd:d9:dd:c25:c25:d915:8aa1
1632c19:dd:d9:dd:c25:c25:d915:8aa2/1282c19:dd:d9:dd:c25:c25:d915:8aa2
1642c19:dd:d9:dd:c25:c25:d915:8aa3/1282c19:dd:d9:dd:c25:c25:d915:8aa3
1652c19:dd:d9:dd:c25:c25:d915:8aa4/1282c19:dd:d9:dd:c25:c25:d915:8aa4
1662c19:dd:d9:dd:c25:c25:d915:8aa5/1282c19:dd:d9:dd:c25:c25:d915:8aa5
1672c19:dd:d9:dd:c25:c25:d915:8aa6/1282c19:dd:d9:dd:c25:c25:d915:8aa6
1682c19:dd:d9:dd:c25:c25:d915:8aa7/1282c19:dd:d9:dd:c25:c25:d915:8aa7
1692c19:dd:d9:dd:c25:c25:d915:8aa8/1282c19:dd:d9:dd:c25:c25:d915:8aa8
1702c19:dd:d9:dd:c25:c25:d915:8aa9/1282c19:dd:d9:dd:c25:c25:d915:8aa9
1712c19:dd:d9:dd:c25:c25:d915:8aaa/1282c19:dd:d9:dd:c25:c25:d915:8aaa
1722c19:dd:d9:dd:c25:c25:d915:8aab/1282c19:dd:d9:dd:c25:c25:d915:8aab
1732c19:dd:d9:dd:c25:c25:d915:8aac/1282c19:dd:d9:dd:c25:c25:d915:8aac
1742c19:dd:d9:dd:c25:c25:d915:8aad/1282c19:dd:d9:dd:c25:c25:d915:8aad
1752c19:dd:d9:dd:c25:c25:d915:8aae/1282c19:dd:d9:dd:c25:c25:d915:8aae
1762c19:dd:d9:dd:c25:c25:d915:8aaf/1282c19:dd:d9:dd:c25:c25:d915:8aaf
1772c19:dd:d9:dd:c25:c25:d915:8ab0/1282c19:dd:d9:dd:c25:c25:d915:8ab0
1782c19:dd:d9:dd:c25:c25:d915:8ab1/1282c19:dd:d9:dd:c25:c25:d915:8ab1
1792c19:dd:d9:dd:c25:c25:d915:8ab2/1282c19:dd:d9:dd:c25:c25:d915:8ab2
1802c19:dd:d9:dd:c25:c25:d915:8ab3/1282c19:dd:d9:dd:c25:c25:d915:8ab3
1812c19:dd:d9:dd:c25:c25:d915:8ab4/1282c19:dd:d9:dd:c25:c25:d915:8ab4
1822c19:dd:d9:dd:c25:c25:d915:8ab5/1282c19:dd:d9:dd:c25:c25:d915:8ab5
1832c19:dd:d9:dd:c25:c25:d915:8ab6/1282c19:dd:d9:dd:c25:c25:d915:8ab6
1842c19:dd:d9:dd:c25:c25:d915:8ab7/1282c19:dd:d9:dd:c25:c25:d915:8ab7
1852c19:dd:d9:dd:c25:c25:d915:8ab8/1282c19:dd:d9:dd:c25:c25:d915:8ab8
1862c19:dd:d9:dd:c25:c25:d915:8ab9/1282c19:dd:d9:dd:c25:c25:d915:8ab9
1872c19:dd:d9:dd:c25:c25:d915:8aba/1282c19:dd:d9:dd:c25:c25:d915:8aba
1882c19:dd:d9:dd:c25:c25:d915:8abb/1282c19:dd:d9:dd:c25:c25:d915:8abb
1892c19:dd:d9:dd:c25:c25:d915:8abc/1282c19:dd:d9:dd:c25:c25:d915:8abc
1902c19:dd:d9:dd:c25:c25:d915:8abd/1282c19:dd:d9:dd:c25:c25:d915:8abd
1912c19:dd:d9:dd:c25:c25:d915:8abe/1282c19:dd:d9:dd:c25:c25:d915:8abe
1922c19:dd:d9:dd:c25:c25:d915:8abf/1282c19:dd:d9:dd:c25:c25:d915:8abf
1932c19:dd:d9:dd:c25:c25:d915:8ac0/1282c19:dd:d9:dd:c25:c25:d915:8ac0
1942c19:dd:d9:dd:c25:c25:d915:8ac1/1282c19:dd:d9:dd:c25:c25:d915:8ac1
1952c19:dd:d9:dd:c25:c25:d915:8ac2/1282c19:dd:d9:dd:c25:c25:d915:8ac2
1962c19:dd:d9:dd:c25:c25:d915:8ac3/1282c19:dd:d9:dd:c25:c25:d915:8ac3
1972c19:dd:d9:dd:c25:c25:d915:8ac4/1282c19:dd:d9:dd:c25:c25:d915:8ac4
1982c19:dd:d9:dd:c25:c25:d915:8ac5/1282c19:dd:d9:dd:c25:c25:d915:8ac5
1992c19:dd:d9:dd:c25:c25:d915:8ac6/1282c19:dd:d9:dd:c25:c25:d915:8ac6
2002c19:dd:d9:dd:c25:c25:d915:8ac7/1282c19:dd:d9:dd:c25:c25:d915:8ac7
2012c19:dd:d9:dd:c25:c25:d915:8ac8/1282c19:dd:d9:dd:c25:c25:d915:8ac8
2022c19:dd:d9:dd:c25:c25:d915:8ac9/1282c19:dd:d9:dd:c25:c25:d915:8ac9
2032c19:dd:d9:dd:c25:c25:d915:8aca/1282c19:dd:d9:dd:c25:c25:d915:8aca
2042c19:dd:d9:dd:c25:c25:d915:8acb/1282c19:dd:d9:dd:c25:c25:d915:8acb
2052c19:dd:d9:dd:c25:c25:d915:8acc/1282c19:dd:d9:dd:c25:c25:d915:8acc
2062c19:dd:d9:dd:c25:c25:d915:8acd/1282c19:dd:d9:dd:c25:c25:d915:8acd
2072c19:dd:d9:dd:c25:c25:d915:8ace/1282c19:dd:d9:dd:c25:c25:d915:8ace
2082c19:dd:d9:dd:c25:c25:d915:8acf/1282c19:dd:d9:dd:c25:c25:d915:8acf
2092c19:dd:d9:dd:c25:c25:d915:8ad0/1282c19:dd:d9:dd:c25:c25:d915:8ad0
2102c19:dd:d9:dd:c25:c25:d915:8ad1/1282c19:dd:d9:dd:c25:c25:d915:8ad1
2112c19:dd:d9:dd:c25:c25:d915:8ad2/1282c19:dd:d9:dd:c25:c25:d915:8ad2
2122c19:dd:d9:dd:c25:c25:d915:8ad3/1282c19:dd:d9:dd:c25:c25:d915:8ad3
2132c19:dd:d9:dd:c25:c25:d915:8ad4/1282c19:dd:d9:dd:c25:c25:d915:8ad4
2142c19:dd:d9:dd:c25:c25:d915:8ad5/1282c19:dd:d9:dd:c25:c25:d915:8ad5
2152c19:dd:d9:dd:c25:c25:d915:8ad6/1282c19:dd:d9:dd:c25:c25:d915:8ad6
2162c19:dd:d9:dd:c25:c25:d915:8ad7/1282c19:dd:d9:dd:c25:c25:d915:8ad7
2172c19:dd:d9:dd:c25:c25:d915:8ad8/1282c19:dd:d9:dd:c25:c25:d915:8ad8
2182c19:dd:d9:dd:c25:c25:d915:8ad9/1282c19:dd:d9:dd:c25:c25:d915:8ad9
2192c19:dd:d9:dd:c25:c25:d915:8ada/1282c19:dd:d9:dd:c25:c25:d915:8ada
2202c19:dd:d9:dd:c25:c25:d915:8adb/1282c19:dd:d9:dd:c25:c25:d915:8adb
2212c19:dd:d9:dd:c25:c25:d915:8adc/1282c19:dd:d9:dd:c25:c25:d915:8adc
2222c19:dd:d9:dd:c25:c25:d915:8add/1282c19:dd:d9:dd:c25:c25:d915:8add
2232c19:dd:d9:dd:c25:c25:d915:8ade/1282c19:dd:d9:dd:c25:c25:d915:8ade
2242c19:dd:d9:dd:c25:c25:d915:8adf/1282c19:dd:d9:dd:c25:c25:d915:8adf
2252c19:dd:d9:dd:c25:c25:d915:8ae0/1282c19:dd:d9:dd:c25:c25:d915:8ae0
2262c19:dd:d9:dd:c25:c25:d915:8ae1/1282c19:dd:d9:dd:c25:c25:d915:8ae1
2272c19:dd:d9:dd:c25:c25:d915:8ae2/1282c19:dd:d9:dd:c25:c25:d915:8ae2
2282c19:dd:d9:dd:c25:c25:d915:8ae3/1282c19:dd:d9:dd:c25:c25:d915:8ae3
2292c19:dd:d9:dd:c25:c25:d915:8ae4/1282c19:dd:d9:dd:c25:c25:d915:8ae4
2302c19:dd:d9:dd:c25:c25:d915:8ae5/1282c19:dd:d9:dd:c25:c25:d915:8ae5
2312c19:dd:d9:dd:c25:c25:d915:8ae6/1282c19:dd:d9:dd:c25:c25:d915:8ae6
2322c19:dd:d9:dd:c25:c25:d915:8ae7/1282c19:dd:d9:dd:c25:c25:d915:8ae7
2332c19:dd:d9:dd:c25:c25:d915:8ae8/1282c19:dd:d9:dd:c25:c25:d915:8ae8
2342c19:dd:d9:dd:c25:c25:d915:8ae9/1282c19:dd:d9:dd:c25:c25:d915:8ae9
2352c19:dd:d9:dd:c25:c25:d915:8aea/1282c19:dd:d9:dd:c25:c25:d915:8aea
2362c19:dd:d9:dd:c25:c25:d915:8aeb/1282c19:dd:d9:dd:c25:c25:d915:8aeb
2372c19:dd:d9:dd:c25:c25:d915:8aec/1282c19:dd:d9:dd:c25:c25:d915:8aec
2382c19:dd:d9:dd:c25:c25:d915:8aed/1282c19:dd:d9:dd:c25:c25:d915:8aed
2392c19:dd:d9:dd:c25:c25:d915:8aee/1282c19:dd:d9:dd:c25:c25:d915:8aee
2402c19:dd:d9:dd:c25:c25:d915:8aef/1282c19:dd:d9:dd:c25:c25:d915:8aef
2412c19:dd:d9:dd:c25:c25:d915:8af0/1282c19:dd:d9:dd:c25:c25:d915:8af0
2422c19:dd:d9:dd:c25:c25:d915:8af1/1282c19:dd:d9:dd:c25:c25:d915:8af1
2432c19:dd:d9:dd:c25:c25:d915:8af2/1282c19:dd:d9:dd:c25:c25:d915:8af2
2442c19:dd:d9:dd:c25:c25:d915:8af3/1282c19:dd:d9:dd:c25:c25:d915:8af3
2452c19:dd:d9:dd:c25:c25:d915:8af4/1282c19:dd:d9:dd:c25:c25:d915:8af4
2462c19:dd:d9:dd:c25:c25:d915:8af5/1282c19:dd:d9:dd:c25:c25:d915:8af5
2472c19:dd:d9:dd:c25:c25:d915:8af6/1282c19:dd:d9:dd:c25:c25:d915:8af6
2482c19:dd:d9:dd:c25:c25:d915:8af7/1282c19:dd:d9:dd:c25:c25:d915:8af7
2492c19:dd:d9:dd:c25:c25:d915:8af8/1282c19:dd:d9:dd:c25:c25:d915:8af8
2502c19:dd:d9:dd:c25:c25:d915:8af9/1282c19:dd:d9:dd:c25:c25:d915:8af9
2512c19:dd:d9:dd:c25:c25:d915:8afa/1282c19:dd:d9:dd:c25:c25:d915:8afa
2522c19:dd:d9:dd:c25:c25:d915:8afb/1282c19:dd:d9:dd:c25:c25:d915:8afb
2532c19:dd:d9:dd:c25:c25:d915:8afc/1282c19:dd:d9:dd:c25:c25:d915:8afc
2542c19:dd:d9:dd:c25:c25:d915:8afd/1282c19:dd:d9:dd:c25:c25:d915:8afd
2552c19:dd:d9:dd:c25:c25:d915:8afe/1282c19:dd:d9:dd:c25:c25:d915:8afe
2562c19:dd:d9:dd:c25:c25:d915:8aff/1282c19:dd:d9:dd:c25:c25:d915:8aff

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.