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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:ec00:c25:c25e:dd:dd:db00/120
First address
2c19:dd:ec00:c25:c25e:dd:dd:db00
Last address
2c19:dd:ec00:c25:c25e:dd:dd:dbff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:ec00:0c25:c25e:00dd:00dd:db00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
b.d.d.d.0.0.d.d.0.0.e.5.2.c.5.2.c.0.0.0.c.e.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:ec00:c25:c25e:dd:dd:db00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:ec00:c25:c25e:dd:dd:db00/1282c19:dd:ec00:c25:c25e:dd:dd:db00
22c19:dd:ec00:c25:c25e:dd:dd:db01/1282c19:dd:ec00:c25:c25e:dd:dd:db01
32c19:dd:ec00:c25:c25e:dd:dd:db02/1282c19:dd:ec00:c25:c25e:dd:dd:db02
42c19:dd:ec00:c25:c25e:dd:dd:db03/1282c19:dd:ec00:c25:c25e:dd:dd:db03
52c19:dd:ec00:c25:c25e:dd:dd:db04/1282c19:dd:ec00:c25:c25e:dd:dd:db04
62c19:dd:ec00:c25:c25e:dd:dd:db05/1282c19:dd:ec00:c25:c25e:dd:dd:db05
72c19:dd:ec00:c25:c25e:dd:dd:db06/1282c19:dd:ec00:c25:c25e:dd:dd:db06
82c19:dd:ec00:c25:c25e:dd:dd:db07/1282c19:dd:ec00:c25:c25e:dd:dd:db07
92c19:dd:ec00:c25:c25e:dd:dd:db08/1282c19:dd:ec00:c25:c25e:dd:dd:db08
102c19:dd:ec00:c25:c25e:dd:dd:db09/1282c19:dd:ec00:c25:c25e:dd:dd:db09
112c19:dd:ec00:c25:c25e:dd:dd:db0a/1282c19:dd:ec00:c25:c25e:dd:dd:db0a
122c19:dd:ec00:c25:c25e:dd:dd:db0b/1282c19:dd:ec00:c25:c25e:dd:dd:db0b
132c19:dd:ec00:c25:c25e:dd:dd:db0c/1282c19:dd:ec00:c25:c25e:dd:dd:db0c
142c19:dd:ec00:c25:c25e:dd:dd:db0d/1282c19:dd:ec00:c25:c25e:dd:dd:db0d
152c19:dd:ec00:c25:c25e:dd:dd:db0e/1282c19:dd:ec00:c25:c25e:dd:dd:db0e
162c19:dd:ec00:c25:c25e:dd:dd:db0f/1282c19:dd:ec00:c25:c25e:dd:dd:db0f
172c19:dd:ec00:c25:c25e:dd:dd:db10/1282c19:dd:ec00:c25:c25e:dd:dd:db10
182c19:dd:ec00:c25:c25e:dd:dd:db11/1282c19:dd:ec00:c25:c25e:dd:dd:db11
192c19:dd:ec00:c25:c25e:dd:dd:db12/1282c19:dd:ec00:c25:c25e:dd:dd:db12
202c19:dd:ec00:c25:c25e:dd:dd:db13/1282c19:dd:ec00:c25:c25e:dd:dd:db13
212c19:dd:ec00:c25:c25e:dd:dd:db14/1282c19:dd:ec00:c25:c25e:dd:dd:db14
222c19:dd:ec00:c25:c25e:dd:dd:db15/1282c19:dd:ec00:c25:c25e:dd:dd:db15
232c19:dd:ec00:c25:c25e:dd:dd:db16/1282c19:dd:ec00:c25:c25e:dd:dd:db16
242c19:dd:ec00:c25:c25e:dd:dd:db17/1282c19:dd:ec00:c25:c25e:dd:dd:db17
252c19:dd:ec00:c25:c25e:dd:dd:db18/1282c19:dd:ec00:c25:c25e:dd:dd:db18
262c19:dd:ec00:c25:c25e:dd:dd:db19/1282c19:dd:ec00:c25:c25e:dd:dd:db19
272c19:dd:ec00:c25:c25e:dd:dd:db1a/1282c19:dd:ec00:c25:c25e:dd:dd:db1a
282c19:dd:ec00:c25:c25e:dd:dd:db1b/1282c19:dd:ec00:c25:c25e:dd:dd:db1b
292c19:dd:ec00:c25:c25e:dd:dd:db1c/1282c19:dd:ec00:c25:c25e:dd:dd:db1c
302c19:dd:ec00:c25:c25e:dd:dd:db1d/1282c19:dd:ec00:c25:c25e:dd:dd:db1d
312c19:dd:ec00:c25:c25e:dd:dd:db1e/1282c19:dd:ec00:c25:c25e:dd:dd:db1e
322c19:dd:ec00:c25:c25e:dd:dd:db1f/1282c19:dd:ec00:c25:c25e:dd:dd:db1f
332c19:dd:ec00:c25:c25e:dd:dd:db20/1282c19:dd:ec00:c25:c25e:dd:dd:db20
342c19:dd:ec00:c25:c25e:dd:dd:db21/1282c19:dd:ec00:c25:c25e:dd:dd:db21
352c19:dd:ec00:c25:c25e:dd:dd:db22/1282c19:dd:ec00:c25:c25e:dd:dd:db22
362c19:dd:ec00:c25:c25e:dd:dd:db23/1282c19:dd:ec00:c25:c25e:dd:dd:db23
372c19:dd:ec00:c25:c25e:dd:dd:db24/1282c19:dd:ec00:c25:c25e:dd:dd:db24
382c19:dd:ec00:c25:c25e:dd:dd:db25/1282c19:dd:ec00:c25:c25e:dd:dd:db25
392c19:dd:ec00:c25:c25e:dd:dd:db26/1282c19:dd:ec00:c25:c25e:dd:dd:db26
402c19:dd:ec00:c25:c25e:dd:dd:db27/1282c19:dd:ec00:c25:c25e:dd:dd:db27
412c19:dd:ec00:c25:c25e:dd:dd:db28/1282c19:dd:ec00:c25:c25e:dd:dd:db28
422c19:dd:ec00:c25:c25e:dd:dd:db29/1282c19:dd:ec00:c25:c25e:dd:dd:db29
432c19:dd:ec00:c25:c25e:dd:dd:db2a/1282c19:dd:ec00:c25:c25e:dd:dd:db2a
442c19:dd:ec00:c25:c25e:dd:dd:db2b/1282c19:dd:ec00:c25:c25e:dd:dd:db2b
452c19:dd:ec00:c25:c25e:dd:dd:db2c/1282c19:dd:ec00:c25:c25e:dd:dd:db2c
462c19:dd:ec00:c25:c25e:dd:dd:db2d/1282c19:dd:ec00:c25:c25e:dd:dd:db2d
472c19:dd:ec00:c25:c25e:dd:dd:db2e/1282c19:dd:ec00:c25:c25e:dd:dd:db2e
482c19:dd:ec00:c25:c25e:dd:dd:db2f/1282c19:dd:ec00:c25:c25e:dd:dd:db2f
492c19:dd:ec00:c25:c25e:dd:dd:db30/1282c19:dd:ec00:c25:c25e:dd:dd:db30
502c19:dd:ec00:c25:c25e:dd:dd:db31/1282c19:dd:ec00:c25:c25e:dd:dd:db31
512c19:dd:ec00:c25:c25e:dd:dd:db32/1282c19:dd:ec00:c25:c25e:dd:dd:db32
522c19:dd:ec00:c25:c25e:dd:dd:db33/1282c19:dd:ec00:c25:c25e:dd:dd:db33
532c19:dd:ec00:c25:c25e:dd:dd:db34/1282c19:dd:ec00:c25:c25e:dd:dd:db34
542c19:dd:ec00:c25:c25e:dd:dd:db35/1282c19:dd:ec00:c25:c25e:dd:dd:db35
552c19:dd:ec00:c25:c25e:dd:dd:db36/1282c19:dd:ec00:c25:c25e:dd:dd:db36
562c19:dd:ec00:c25:c25e:dd:dd:db37/1282c19:dd:ec00:c25:c25e:dd:dd:db37
572c19:dd:ec00:c25:c25e:dd:dd:db38/1282c19:dd:ec00:c25:c25e:dd:dd:db38
582c19:dd:ec00:c25:c25e:dd:dd:db39/1282c19:dd:ec00:c25:c25e:dd:dd:db39
592c19:dd:ec00:c25:c25e:dd:dd:db3a/1282c19:dd:ec00:c25:c25e:dd:dd:db3a
602c19:dd:ec00:c25:c25e:dd:dd:db3b/1282c19:dd:ec00:c25:c25e:dd:dd:db3b
612c19:dd:ec00:c25:c25e:dd:dd:db3c/1282c19:dd:ec00:c25:c25e:dd:dd:db3c
622c19:dd:ec00:c25:c25e:dd:dd:db3d/1282c19:dd:ec00:c25:c25e:dd:dd:db3d
632c19:dd:ec00:c25:c25e:dd:dd:db3e/1282c19:dd:ec00:c25:c25e:dd:dd:db3e
642c19:dd:ec00:c25:c25e:dd:dd:db3f/1282c19:dd:ec00:c25:c25e:dd:dd:db3f
652c19:dd:ec00:c25:c25e:dd:dd:db40/1282c19:dd:ec00:c25:c25e:dd:dd:db40
662c19:dd:ec00:c25:c25e:dd:dd:db41/1282c19:dd:ec00:c25:c25e:dd:dd:db41
672c19:dd:ec00:c25:c25e:dd:dd:db42/1282c19:dd:ec00:c25:c25e:dd:dd:db42
682c19:dd:ec00:c25:c25e:dd:dd:db43/1282c19:dd:ec00:c25:c25e:dd:dd:db43
692c19:dd:ec00:c25:c25e:dd:dd:db44/1282c19:dd:ec00:c25:c25e:dd:dd:db44
702c19:dd:ec00:c25:c25e:dd:dd:db45/1282c19:dd:ec00:c25:c25e:dd:dd:db45
712c19:dd:ec00:c25:c25e:dd:dd:db46/1282c19:dd:ec00:c25:c25e:dd:dd:db46
722c19:dd:ec00:c25:c25e:dd:dd:db47/1282c19:dd:ec00:c25:c25e:dd:dd:db47
732c19:dd:ec00:c25:c25e:dd:dd:db48/1282c19:dd:ec00:c25:c25e:dd:dd:db48
742c19:dd:ec00:c25:c25e:dd:dd:db49/1282c19:dd:ec00:c25:c25e:dd:dd:db49
752c19:dd:ec00:c25:c25e:dd:dd:db4a/1282c19:dd:ec00:c25:c25e:dd:dd:db4a
762c19:dd:ec00:c25:c25e:dd:dd:db4b/1282c19:dd:ec00:c25:c25e:dd:dd:db4b
772c19:dd:ec00:c25:c25e:dd:dd:db4c/1282c19:dd:ec00:c25:c25e:dd:dd:db4c
782c19:dd:ec00:c25:c25e:dd:dd:db4d/1282c19:dd:ec00:c25:c25e:dd:dd:db4d
792c19:dd:ec00:c25:c25e:dd:dd:db4e/1282c19:dd:ec00:c25:c25e:dd:dd:db4e
802c19:dd:ec00:c25:c25e:dd:dd:db4f/1282c19:dd:ec00:c25:c25e:dd:dd:db4f
812c19:dd:ec00:c25:c25e:dd:dd:db50/1282c19:dd:ec00:c25:c25e:dd:dd:db50
822c19:dd:ec00:c25:c25e:dd:dd:db51/1282c19:dd:ec00:c25:c25e:dd:dd:db51
832c19:dd:ec00:c25:c25e:dd:dd:db52/1282c19:dd:ec00:c25:c25e:dd:dd:db52
842c19:dd:ec00:c25:c25e:dd:dd:db53/1282c19:dd:ec00:c25:c25e:dd:dd:db53
852c19:dd:ec00:c25:c25e:dd:dd:db54/1282c19:dd:ec00:c25:c25e:dd:dd:db54
862c19:dd:ec00:c25:c25e:dd:dd:db55/1282c19:dd:ec00:c25:c25e:dd:dd:db55
872c19:dd:ec00:c25:c25e:dd:dd:db56/1282c19:dd:ec00:c25:c25e:dd:dd:db56
882c19:dd:ec00:c25:c25e:dd:dd:db57/1282c19:dd:ec00:c25:c25e:dd:dd:db57
892c19:dd:ec00:c25:c25e:dd:dd:db58/1282c19:dd:ec00:c25:c25e:dd:dd:db58
902c19:dd:ec00:c25:c25e:dd:dd:db59/1282c19:dd:ec00:c25:c25e:dd:dd:db59
912c19:dd:ec00:c25:c25e:dd:dd:db5a/1282c19:dd:ec00:c25:c25e:dd:dd:db5a
922c19:dd:ec00:c25:c25e:dd:dd:db5b/1282c19:dd:ec00:c25:c25e:dd:dd:db5b
932c19:dd:ec00:c25:c25e:dd:dd:db5c/1282c19:dd:ec00:c25:c25e:dd:dd:db5c
942c19:dd:ec00:c25:c25e:dd:dd:db5d/1282c19:dd:ec00:c25:c25e:dd:dd:db5d
952c19:dd:ec00:c25:c25e:dd:dd:db5e/1282c19:dd:ec00:c25:c25e:dd:dd:db5e
962c19:dd:ec00:c25:c25e:dd:dd:db5f/1282c19:dd:ec00:c25:c25e:dd:dd:db5f
972c19:dd:ec00:c25:c25e:dd:dd:db60/1282c19:dd:ec00:c25:c25e:dd:dd:db60
982c19:dd:ec00:c25:c25e:dd:dd:db61/1282c19:dd:ec00:c25:c25e:dd:dd:db61
992c19:dd:ec00:c25:c25e:dd:dd:db62/1282c19:dd:ec00:c25:c25e:dd:dd:db62
1002c19:dd:ec00:c25:c25e:dd:dd:db63/1282c19:dd:ec00:c25:c25e:dd:dd:db63
1012c19:dd:ec00:c25:c25e:dd:dd:db64/1282c19:dd:ec00:c25:c25e:dd:dd:db64
1022c19:dd:ec00:c25:c25e:dd:dd:db65/1282c19:dd:ec00:c25:c25e:dd:dd:db65
1032c19:dd:ec00:c25:c25e:dd:dd:db66/1282c19:dd:ec00:c25:c25e:dd:dd:db66
1042c19:dd:ec00:c25:c25e:dd:dd:db67/1282c19:dd:ec00:c25:c25e:dd:dd:db67
1052c19:dd:ec00:c25:c25e:dd:dd:db68/1282c19:dd:ec00:c25:c25e:dd:dd:db68
1062c19:dd:ec00:c25:c25e:dd:dd:db69/1282c19:dd:ec00:c25:c25e:dd:dd:db69
1072c19:dd:ec00:c25:c25e:dd:dd:db6a/1282c19:dd:ec00:c25:c25e:dd:dd:db6a
1082c19:dd:ec00:c25:c25e:dd:dd:db6b/1282c19:dd:ec00:c25:c25e:dd:dd:db6b
1092c19:dd:ec00:c25:c25e:dd:dd:db6c/1282c19:dd:ec00:c25:c25e:dd:dd:db6c
1102c19:dd:ec00:c25:c25e:dd:dd:db6d/1282c19:dd:ec00:c25:c25e:dd:dd:db6d
1112c19:dd:ec00:c25:c25e:dd:dd:db6e/1282c19:dd:ec00:c25:c25e:dd:dd:db6e
1122c19:dd:ec00:c25:c25e:dd:dd:db6f/1282c19:dd:ec00:c25:c25e:dd:dd:db6f
1132c19:dd:ec00:c25:c25e:dd:dd:db70/1282c19:dd:ec00:c25:c25e:dd:dd:db70
1142c19:dd:ec00:c25:c25e:dd:dd:db71/1282c19:dd:ec00:c25:c25e:dd:dd:db71
1152c19:dd:ec00:c25:c25e:dd:dd:db72/1282c19:dd:ec00:c25:c25e:dd:dd:db72
1162c19:dd:ec00:c25:c25e:dd:dd:db73/1282c19:dd:ec00:c25:c25e:dd:dd:db73
1172c19:dd:ec00:c25:c25e:dd:dd:db74/1282c19:dd:ec00:c25:c25e:dd:dd:db74
1182c19:dd:ec00:c25:c25e:dd:dd:db75/1282c19:dd:ec00:c25:c25e:dd:dd:db75
1192c19:dd:ec00:c25:c25e:dd:dd:db76/1282c19:dd:ec00:c25:c25e:dd:dd:db76
1202c19:dd:ec00:c25:c25e:dd:dd:db77/1282c19:dd:ec00:c25:c25e:dd:dd:db77
1212c19:dd:ec00:c25:c25e:dd:dd:db78/1282c19:dd:ec00:c25:c25e:dd:dd:db78
1222c19:dd:ec00:c25:c25e:dd:dd:db79/1282c19:dd:ec00:c25:c25e:dd:dd:db79
1232c19:dd:ec00:c25:c25e:dd:dd:db7a/1282c19:dd:ec00:c25:c25e:dd:dd:db7a
1242c19:dd:ec00:c25:c25e:dd:dd:db7b/1282c19:dd:ec00:c25:c25e:dd:dd:db7b
1252c19:dd:ec00:c25:c25e:dd:dd:db7c/1282c19:dd:ec00:c25:c25e:dd:dd:db7c
1262c19:dd:ec00:c25:c25e:dd:dd:db7d/1282c19:dd:ec00:c25:c25e:dd:dd:db7d
1272c19:dd:ec00:c25:c25e:dd:dd:db7e/1282c19:dd:ec00:c25:c25e:dd:dd:db7e
1282c19:dd:ec00:c25:c25e:dd:dd:db7f/1282c19:dd:ec00:c25:c25e:dd:dd:db7f
1292c19:dd:ec00:c25:c25e:dd:dd:db80/1282c19:dd:ec00:c25:c25e:dd:dd:db80
1302c19:dd:ec00:c25:c25e:dd:dd:db81/1282c19:dd:ec00:c25:c25e:dd:dd:db81
1312c19:dd:ec00:c25:c25e:dd:dd:db82/1282c19:dd:ec00:c25:c25e:dd:dd:db82
1322c19:dd:ec00:c25:c25e:dd:dd:db83/1282c19:dd:ec00:c25:c25e:dd:dd:db83
1332c19:dd:ec00:c25:c25e:dd:dd:db84/1282c19:dd:ec00:c25:c25e:dd:dd:db84
1342c19:dd:ec00:c25:c25e:dd:dd:db85/1282c19:dd:ec00:c25:c25e:dd:dd:db85
1352c19:dd:ec00:c25:c25e:dd:dd:db86/1282c19:dd:ec00:c25:c25e:dd:dd:db86
1362c19:dd:ec00:c25:c25e:dd:dd:db87/1282c19:dd:ec00:c25:c25e:dd:dd:db87
1372c19:dd:ec00:c25:c25e:dd:dd:db88/1282c19:dd:ec00:c25:c25e:dd:dd:db88
1382c19:dd:ec00:c25:c25e:dd:dd:db89/1282c19:dd:ec00:c25:c25e:dd:dd:db89
1392c19:dd:ec00:c25:c25e:dd:dd:db8a/1282c19:dd:ec00:c25:c25e:dd:dd:db8a
1402c19:dd:ec00:c25:c25e:dd:dd:db8b/1282c19:dd:ec00:c25:c25e:dd:dd:db8b
1412c19:dd:ec00:c25:c25e:dd:dd:db8c/1282c19:dd:ec00:c25:c25e:dd:dd:db8c
1422c19:dd:ec00:c25:c25e:dd:dd:db8d/1282c19:dd:ec00:c25:c25e:dd:dd:db8d
1432c19:dd:ec00:c25:c25e:dd:dd:db8e/1282c19:dd:ec00:c25:c25e:dd:dd:db8e
1442c19:dd:ec00:c25:c25e:dd:dd:db8f/1282c19:dd:ec00:c25:c25e:dd:dd:db8f
1452c19:dd:ec00:c25:c25e:dd:dd:db90/1282c19:dd:ec00:c25:c25e:dd:dd:db90
1462c19:dd:ec00:c25:c25e:dd:dd:db91/1282c19:dd:ec00:c25:c25e:dd:dd:db91
1472c19:dd:ec00:c25:c25e:dd:dd:db92/1282c19:dd:ec00:c25:c25e:dd:dd:db92
1482c19:dd:ec00:c25:c25e:dd:dd:db93/1282c19:dd:ec00:c25:c25e:dd:dd:db93
1492c19:dd:ec00:c25:c25e:dd:dd:db94/1282c19:dd:ec00:c25:c25e:dd:dd:db94
1502c19:dd:ec00:c25:c25e:dd:dd:db95/1282c19:dd:ec00:c25:c25e:dd:dd:db95
1512c19:dd:ec00:c25:c25e:dd:dd:db96/1282c19:dd:ec00:c25:c25e:dd:dd:db96
1522c19:dd:ec00:c25:c25e:dd:dd:db97/1282c19:dd:ec00:c25:c25e:dd:dd:db97
1532c19:dd:ec00:c25:c25e:dd:dd:db98/1282c19:dd:ec00:c25:c25e:dd:dd:db98
1542c19:dd:ec00:c25:c25e:dd:dd:db99/1282c19:dd:ec00:c25:c25e:dd:dd:db99
1552c19:dd:ec00:c25:c25e:dd:dd:db9a/1282c19:dd:ec00:c25:c25e:dd:dd:db9a
1562c19:dd:ec00:c25:c25e:dd:dd:db9b/1282c19:dd:ec00:c25:c25e:dd:dd:db9b
1572c19:dd:ec00:c25:c25e:dd:dd:db9c/1282c19:dd:ec00:c25:c25e:dd:dd:db9c
1582c19:dd:ec00:c25:c25e:dd:dd:db9d/1282c19:dd:ec00:c25:c25e:dd:dd:db9d
1592c19:dd:ec00:c25:c25e:dd:dd:db9e/1282c19:dd:ec00:c25:c25e:dd:dd:db9e
1602c19:dd:ec00:c25:c25e:dd:dd:db9f/1282c19:dd:ec00:c25:c25e:dd:dd:db9f
1612c19:dd:ec00:c25:c25e:dd:dd:dba0/1282c19:dd:ec00:c25:c25e:dd:dd:dba0
1622c19:dd:ec00:c25:c25e:dd:dd:dba1/1282c19:dd:ec00:c25:c25e:dd:dd:dba1
1632c19:dd:ec00:c25:c25e:dd:dd:dba2/1282c19:dd:ec00:c25:c25e:dd:dd:dba2
1642c19:dd:ec00:c25:c25e:dd:dd:dba3/1282c19:dd:ec00:c25:c25e:dd:dd:dba3
1652c19:dd:ec00:c25:c25e:dd:dd:dba4/1282c19:dd:ec00:c25:c25e:dd:dd:dba4
1662c19:dd:ec00:c25:c25e:dd:dd:dba5/1282c19:dd:ec00:c25:c25e:dd:dd:dba5
1672c19:dd:ec00:c25:c25e:dd:dd:dba6/1282c19:dd:ec00:c25:c25e:dd:dd:dba6
1682c19:dd:ec00:c25:c25e:dd:dd:dba7/1282c19:dd:ec00:c25:c25e:dd:dd:dba7
1692c19:dd:ec00:c25:c25e:dd:dd:dba8/1282c19:dd:ec00:c25:c25e:dd:dd:dba8
1702c19:dd:ec00:c25:c25e:dd:dd:dba9/1282c19:dd:ec00:c25:c25e:dd:dd:dba9
1712c19:dd:ec00:c25:c25e:dd:dd:dbaa/1282c19:dd:ec00:c25:c25e:dd:dd:dbaa
1722c19:dd:ec00:c25:c25e:dd:dd:dbab/1282c19:dd:ec00:c25:c25e:dd:dd:dbab
1732c19:dd:ec00:c25:c25e:dd:dd:dbac/1282c19:dd:ec00:c25:c25e:dd:dd:dbac
1742c19:dd:ec00:c25:c25e:dd:dd:dbad/1282c19:dd:ec00:c25:c25e:dd:dd:dbad
1752c19:dd:ec00:c25:c25e:dd:dd:dbae/1282c19:dd:ec00:c25:c25e:dd:dd:dbae
1762c19:dd:ec00:c25:c25e:dd:dd:dbaf/1282c19:dd:ec00:c25:c25e:dd:dd:dbaf
1772c19:dd:ec00:c25:c25e:dd:dd:dbb0/1282c19:dd:ec00:c25:c25e:dd:dd:dbb0
1782c19:dd:ec00:c25:c25e:dd:dd:dbb1/1282c19:dd:ec00:c25:c25e:dd:dd:dbb1
1792c19:dd:ec00:c25:c25e:dd:dd:dbb2/1282c19:dd:ec00:c25:c25e:dd:dd:dbb2
1802c19:dd:ec00:c25:c25e:dd:dd:dbb3/1282c19:dd:ec00:c25:c25e:dd:dd:dbb3
1812c19:dd:ec00:c25:c25e:dd:dd:dbb4/1282c19:dd:ec00:c25:c25e:dd:dd:dbb4
1822c19:dd:ec00:c25:c25e:dd:dd:dbb5/1282c19:dd:ec00:c25:c25e:dd:dd:dbb5
1832c19:dd:ec00:c25:c25e:dd:dd:dbb6/1282c19:dd:ec00:c25:c25e:dd:dd:dbb6
1842c19:dd:ec00:c25:c25e:dd:dd:dbb7/1282c19:dd:ec00:c25:c25e:dd:dd:dbb7
1852c19:dd:ec00:c25:c25e:dd:dd:dbb8/1282c19:dd:ec00:c25:c25e:dd:dd:dbb8
1862c19:dd:ec00:c25:c25e:dd:dd:dbb9/1282c19:dd:ec00:c25:c25e:dd:dd:dbb9
1872c19:dd:ec00:c25:c25e:dd:dd:dbba/1282c19:dd:ec00:c25:c25e:dd:dd:dbba
1882c19:dd:ec00:c25:c25e:dd:dd:dbbb/1282c19:dd:ec00:c25:c25e:dd:dd:dbbb
1892c19:dd:ec00:c25:c25e:dd:dd:dbbc/1282c19:dd:ec00:c25:c25e:dd:dd:dbbc
1902c19:dd:ec00:c25:c25e:dd:dd:dbbd/1282c19:dd:ec00:c25:c25e:dd:dd:dbbd
1912c19:dd:ec00:c25:c25e:dd:dd:dbbe/1282c19:dd:ec00:c25:c25e:dd:dd:dbbe
1922c19:dd:ec00:c25:c25e:dd:dd:dbbf/1282c19:dd:ec00:c25:c25e:dd:dd:dbbf
1932c19:dd:ec00:c25:c25e:dd:dd:dbc0/1282c19:dd:ec00:c25:c25e:dd:dd:dbc0
1942c19:dd:ec00:c25:c25e:dd:dd:dbc1/1282c19:dd:ec00:c25:c25e:dd:dd:dbc1
1952c19:dd:ec00:c25:c25e:dd:dd:dbc2/1282c19:dd:ec00:c25:c25e:dd:dd:dbc2
1962c19:dd:ec00:c25:c25e:dd:dd:dbc3/1282c19:dd:ec00:c25:c25e:dd:dd:dbc3
1972c19:dd:ec00:c25:c25e:dd:dd:dbc4/1282c19:dd:ec00:c25:c25e:dd:dd:dbc4
1982c19:dd:ec00:c25:c25e:dd:dd:dbc5/1282c19:dd:ec00:c25:c25e:dd:dd:dbc5
1992c19:dd:ec00:c25:c25e:dd:dd:dbc6/1282c19:dd:ec00:c25:c25e:dd:dd:dbc6
2002c19:dd:ec00:c25:c25e:dd:dd:dbc7/1282c19:dd:ec00:c25:c25e:dd:dd:dbc7
2012c19:dd:ec00:c25:c25e:dd:dd:dbc8/1282c19:dd:ec00:c25:c25e:dd:dd:dbc8
2022c19:dd:ec00:c25:c25e:dd:dd:dbc9/1282c19:dd:ec00:c25:c25e:dd:dd:dbc9
2032c19:dd:ec00:c25:c25e:dd:dd:dbca/1282c19:dd:ec00:c25:c25e:dd:dd:dbca
2042c19:dd:ec00:c25:c25e:dd:dd:dbcb/1282c19:dd:ec00:c25:c25e:dd:dd:dbcb
2052c19:dd:ec00:c25:c25e:dd:dd:dbcc/1282c19:dd:ec00:c25:c25e:dd:dd:dbcc
2062c19:dd:ec00:c25:c25e:dd:dd:dbcd/1282c19:dd:ec00:c25:c25e:dd:dd:dbcd
2072c19:dd:ec00:c25:c25e:dd:dd:dbce/1282c19:dd:ec00:c25:c25e:dd:dd:dbce
2082c19:dd:ec00:c25:c25e:dd:dd:dbcf/1282c19:dd:ec00:c25:c25e:dd:dd:dbcf
2092c19:dd:ec00:c25:c25e:dd:dd:dbd0/1282c19:dd:ec00:c25:c25e:dd:dd:dbd0
2102c19:dd:ec00:c25:c25e:dd:dd:dbd1/1282c19:dd:ec00:c25:c25e:dd:dd:dbd1
2112c19:dd:ec00:c25:c25e:dd:dd:dbd2/1282c19:dd:ec00:c25:c25e:dd:dd:dbd2
2122c19:dd:ec00:c25:c25e:dd:dd:dbd3/1282c19:dd:ec00:c25:c25e:dd:dd:dbd3
2132c19:dd:ec00:c25:c25e:dd:dd:dbd4/1282c19:dd:ec00:c25:c25e:dd:dd:dbd4
2142c19:dd:ec00:c25:c25e:dd:dd:dbd5/1282c19:dd:ec00:c25:c25e:dd:dd:dbd5
2152c19:dd:ec00:c25:c25e:dd:dd:dbd6/1282c19:dd:ec00:c25:c25e:dd:dd:dbd6
2162c19:dd:ec00:c25:c25e:dd:dd:dbd7/1282c19:dd:ec00:c25:c25e:dd:dd:dbd7
2172c19:dd:ec00:c25:c25e:dd:dd:dbd8/1282c19:dd:ec00:c25:c25e:dd:dd:dbd8
2182c19:dd:ec00:c25:c25e:dd:dd:dbd9/1282c19:dd:ec00:c25:c25e:dd:dd:dbd9
2192c19:dd:ec00:c25:c25e:dd:dd:dbda/1282c19:dd:ec00:c25:c25e:dd:dd:dbda
2202c19:dd:ec00:c25:c25e:dd:dd:dbdb/1282c19:dd:ec00:c25:c25e:dd:dd:dbdb
2212c19:dd:ec00:c25:c25e:dd:dd:dbdc/1282c19:dd:ec00:c25:c25e:dd:dd:dbdc
2222c19:dd:ec00:c25:c25e:dd:dd:dbdd/1282c19:dd:ec00:c25:c25e:dd:dd:dbdd
2232c19:dd:ec00:c25:c25e:dd:dd:dbde/1282c19:dd:ec00:c25:c25e:dd:dd:dbde
2242c19:dd:ec00:c25:c25e:dd:dd:dbdf/1282c19:dd:ec00:c25:c25e:dd:dd:dbdf
2252c19:dd:ec00:c25:c25e:dd:dd:dbe0/1282c19:dd:ec00:c25:c25e:dd:dd:dbe0
2262c19:dd:ec00:c25:c25e:dd:dd:dbe1/1282c19:dd:ec00:c25:c25e:dd:dd:dbe1
2272c19:dd:ec00:c25:c25e:dd:dd:dbe2/1282c19:dd:ec00:c25:c25e:dd:dd:dbe2
2282c19:dd:ec00:c25:c25e:dd:dd:dbe3/1282c19:dd:ec00:c25:c25e:dd:dd:dbe3
2292c19:dd:ec00:c25:c25e:dd:dd:dbe4/1282c19:dd:ec00:c25:c25e:dd:dd:dbe4
2302c19:dd:ec00:c25:c25e:dd:dd:dbe5/1282c19:dd:ec00:c25:c25e:dd:dd:dbe5
2312c19:dd:ec00:c25:c25e:dd:dd:dbe6/1282c19:dd:ec00:c25:c25e:dd:dd:dbe6
2322c19:dd:ec00:c25:c25e:dd:dd:dbe7/1282c19:dd:ec00:c25:c25e:dd:dd:dbe7
2332c19:dd:ec00:c25:c25e:dd:dd:dbe8/1282c19:dd:ec00:c25:c25e:dd:dd:dbe8
2342c19:dd:ec00:c25:c25e:dd:dd:dbe9/1282c19:dd:ec00:c25:c25e:dd:dd:dbe9
2352c19:dd:ec00:c25:c25e:dd:dd:dbea/1282c19:dd:ec00:c25:c25e:dd:dd:dbea
2362c19:dd:ec00:c25:c25e:dd:dd:dbeb/1282c19:dd:ec00:c25:c25e:dd:dd:dbeb
2372c19:dd:ec00:c25:c25e:dd:dd:dbec/1282c19:dd:ec00:c25:c25e:dd:dd:dbec
2382c19:dd:ec00:c25:c25e:dd:dd:dbed/1282c19:dd:ec00:c25:c25e:dd:dd:dbed
2392c19:dd:ec00:c25:c25e:dd:dd:dbee/1282c19:dd:ec00:c25:c25e:dd:dd:dbee
2402c19:dd:ec00:c25:c25e:dd:dd:dbef/1282c19:dd:ec00:c25:c25e:dd:dd:dbef
2412c19:dd:ec00:c25:c25e:dd:dd:dbf0/1282c19:dd:ec00:c25:c25e:dd:dd:dbf0
2422c19:dd:ec00:c25:c25e:dd:dd:dbf1/1282c19:dd:ec00:c25:c25e:dd:dd:dbf1
2432c19:dd:ec00:c25:c25e:dd:dd:dbf2/1282c19:dd:ec00:c25:c25e:dd:dd:dbf2
2442c19:dd:ec00:c25:c25e:dd:dd:dbf3/1282c19:dd:ec00:c25:c25e:dd:dd:dbf3
2452c19:dd:ec00:c25:c25e:dd:dd:dbf4/1282c19:dd:ec00:c25:c25e:dd:dd:dbf4
2462c19:dd:ec00:c25:c25e:dd:dd:dbf5/1282c19:dd:ec00:c25:c25e:dd:dd:dbf5
2472c19:dd:ec00:c25:c25e:dd:dd:dbf6/1282c19:dd:ec00:c25:c25e:dd:dd:dbf6
2482c19:dd:ec00:c25:c25e:dd:dd:dbf7/1282c19:dd:ec00:c25:c25e:dd:dd:dbf7
2492c19:dd:ec00:c25:c25e:dd:dd:dbf8/1282c19:dd:ec00:c25:c25e:dd:dd:dbf8
2502c19:dd:ec00:c25:c25e:dd:dd:dbf9/1282c19:dd:ec00:c25:c25e:dd:dd:dbf9
2512c19:dd:ec00:c25:c25e:dd:dd:dbfa/1282c19:dd:ec00:c25:c25e:dd:dd:dbfa
2522c19:dd:ec00:c25:c25e:dd:dd:dbfb/1282c19:dd:ec00:c25:c25e:dd:dd:dbfb
2532c19:dd:ec00:c25:c25e:dd:dd:dbfc/1282c19:dd:ec00:c25:c25e:dd:dd:dbfc
2542c19:dd:ec00:c25:c25e:dd:dd:dbfd/1282c19:dd:ec00:c25:c25e:dd:dd:dbfd
2552c19:dd:ec00:c25:c25e:dd:dd:dbfe/1282c19:dd:ec00:c25:c25e:dd:dd:dbfe
2562c19:dd:ec00:c25:c25e:dd:dd:dbff/1282c19:dd:ec00:c25:c25e:dd:dd:dbff

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.