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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:c600/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:c600
Last address
2c19:dd:d9:dd:c25:c25a:d00a:c6ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:c600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.c.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:c600/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:c600/1282c19:dd:d9:dd:c25:c25a:d00a:c600
22c19:dd:d9:dd:c25:c25a:d00a:c601/1282c19:dd:d9:dd:c25:c25a:d00a:c601
32c19:dd:d9:dd:c25:c25a:d00a:c602/1282c19:dd:d9:dd:c25:c25a:d00a:c602
42c19:dd:d9:dd:c25:c25a:d00a:c603/1282c19:dd:d9:dd:c25:c25a:d00a:c603
52c19:dd:d9:dd:c25:c25a:d00a:c604/1282c19:dd:d9:dd:c25:c25a:d00a:c604
62c19:dd:d9:dd:c25:c25a:d00a:c605/1282c19:dd:d9:dd:c25:c25a:d00a:c605
72c19:dd:d9:dd:c25:c25a:d00a:c606/1282c19:dd:d9:dd:c25:c25a:d00a:c606
82c19:dd:d9:dd:c25:c25a:d00a:c607/1282c19:dd:d9:dd:c25:c25a:d00a:c607
92c19:dd:d9:dd:c25:c25a:d00a:c608/1282c19:dd:d9:dd:c25:c25a:d00a:c608
102c19:dd:d9:dd:c25:c25a:d00a:c609/1282c19:dd:d9:dd:c25:c25a:d00a:c609
112c19:dd:d9:dd:c25:c25a:d00a:c60a/1282c19:dd:d9:dd:c25:c25a:d00a:c60a
122c19:dd:d9:dd:c25:c25a:d00a:c60b/1282c19:dd:d9:dd:c25:c25a:d00a:c60b
132c19:dd:d9:dd:c25:c25a:d00a:c60c/1282c19:dd:d9:dd:c25:c25a:d00a:c60c
142c19:dd:d9:dd:c25:c25a:d00a:c60d/1282c19:dd:d9:dd:c25:c25a:d00a:c60d
152c19:dd:d9:dd:c25:c25a:d00a:c60e/1282c19:dd:d9:dd:c25:c25a:d00a:c60e
162c19:dd:d9:dd:c25:c25a:d00a:c60f/1282c19:dd:d9:dd:c25:c25a:d00a:c60f
172c19:dd:d9:dd:c25:c25a:d00a:c610/1282c19:dd:d9:dd:c25:c25a:d00a:c610
182c19:dd:d9:dd:c25:c25a:d00a:c611/1282c19:dd:d9:dd:c25:c25a:d00a:c611
192c19:dd:d9:dd:c25:c25a:d00a:c612/1282c19:dd:d9:dd:c25:c25a:d00a:c612
202c19:dd:d9:dd:c25:c25a:d00a:c613/1282c19:dd:d9:dd:c25:c25a:d00a:c613
212c19:dd:d9:dd:c25:c25a:d00a:c614/1282c19:dd:d9:dd:c25:c25a:d00a:c614
222c19:dd:d9:dd:c25:c25a:d00a:c615/1282c19:dd:d9:dd:c25:c25a:d00a:c615
232c19:dd:d9:dd:c25:c25a:d00a:c616/1282c19:dd:d9:dd:c25:c25a:d00a:c616
242c19:dd:d9:dd:c25:c25a:d00a:c617/1282c19:dd:d9:dd:c25:c25a:d00a:c617
252c19:dd:d9:dd:c25:c25a:d00a:c618/1282c19:dd:d9:dd:c25:c25a:d00a:c618
262c19:dd:d9:dd:c25:c25a:d00a:c619/1282c19:dd:d9:dd:c25:c25a:d00a:c619
272c19:dd:d9:dd:c25:c25a:d00a:c61a/1282c19:dd:d9:dd:c25:c25a:d00a:c61a
282c19:dd:d9:dd:c25:c25a:d00a:c61b/1282c19:dd:d9:dd:c25:c25a:d00a:c61b
292c19:dd:d9:dd:c25:c25a:d00a:c61c/1282c19:dd:d9:dd:c25:c25a:d00a:c61c
302c19:dd:d9:dd:c25:c25a:d00a:c61d/1282c19:dd:d9:dd:c25:c25a:d00a:c61d
312c19:dd:d9:dd:c25:c25a:d00a:c61e/1282c19:dd:d9:dd:c25:c25a:d00a:c61e
322c19:dd:d9:dd:c25:c25a:d00a:c61f/1282c19:dd:d9:dd:c25:c25a:d00a:c61f
332c19:dd:d9:dd:c25:c25a:d00a:c620/1282c19:dd:d9:dd:c25:c25a:d00a:c620
342c19:dd:d9:dd:c25:c25a:d00a:c621/1282c19:dd:d9:dd:c25:c25a:d00a:c621
352c19:dd:d9:dd:c25:c25a:d00a:c622/1282c19:dd:d9:dd:c25:c25a:d00a:c622
362c19:dd:d9:dd:c25:c25a:d00a:c623/1282c19:dd:d9:dd:c25:c25a:d00a:c623
372c19:dd:d9:dd:c25:c25a:d00a:c624/1282c19:dd:d9:dd:c25:c25a:d00a:c624
382c19:dd:d9:dd:c25:c25a:d00a:c625/1282c19:dd:d9:dd:c25:c25a:d00a:c625
392c19:dd:d9:dd:c25:c25a:d00a:c626/1282c19:dd:d9:dd:c25:c25a:d00a:c626
402c19:dd:d9:dd:c25:c25a:d00a:c627/1282c19:dd:d9:dd:c25:c25a:d00a:c627
412c19:dd:d9:dd:c25:c25a:d00a:c628/1282c19:dd:d9:dd:c25:c25a:d00a:c628
422c19:dd:d9:dd:c25:c25a:d00a:c629/1282c19:dd:d9:dd:c25:c25a:d00a:c629
432c19:dd:d9:dd:c25:c25a:d00a:c62a/1282c19:dd:d9:dd:c25:c25a:d00a:c62a
442c19:dd:d9:dd:c25:c25a:d00a:c62b/1282c19:dd:d9:dd:c25:c25a:d00a:c62b
452c19:dd:d9:dd:c25:c25a:d00a:c62c/1282c19:dd:d9:dd:c25:c25a:d00a:c62c
462c19:dd:d9:dd:c25:c25a:d00a:c62d/1282c19:dd:d9:dd:c25:c25a:d00a:c62d
472c19:dd:d9:dd:c25:c25a:d00a:c62e/1282c19:dd:d9:dd:c25:c25a:d00a:c62e
482c19:dd:d9:dd:c25:c25a:d00a:c62f/1282c19:dd:d9:dd:c25:c25a:d00a:c62f
492c19:dd:d9:dd:c25:c25a:d00a:c630/1282c19:dd:d9:dd:c25:c25a:d00a:c630
502c19:dd:d9:dd:c25:c25a:d00a:c631/1282c19:dd:d9:dd:c25:c25a:d00a:c631
512c19:dd:d9:dd:c25:c25a:d00a:c632/1282c19:dd:d9:dd:c25:c25a:d00a:c632
522c19:dd:d9:dd:c25:c25a:d00a:c633/1282c19:dd:d9:dd:c25:c25a:d00a:c633
532c19:dd:d9:dd:c25:c25a:d00a:c634/1282c19:dd:d9:dd:c25:c25a:d00a:c634
542c19:dd:d9:dd:c25:c25a:d00a:c635/1282c19:dd:d9:dd:c25:c25a:d00a:c635
552c19:dd:d9:dd:c25:c25a:d00a:c636/1282c19:dd:d9:dd:c25:c25a:d00a:c636
562c19:dd:d9:dd:c25:c25a:d00a:c637/1282c19:dd:d9:dd:c25:c25a:d00a:c637
572c19:dd:d9:dd:c25:c25a:d00a:c638/1282c19:dd:d9:dd:c25:c25a:d00a:c638
582c19:dd:d9:dd:c25:c25a:d00a:c639/1282c19:dd:d9:dd:c25:c25a:d00a:c639
592c19:dd:d9:dd:c25:c25a:d00a:c63a/1282c19:dd:d9:dd:c25:c25a:d00a:c63a
602c19:dd:d9:dd:c25:c25a:d00a:c63b/1282c19:dd:d9:dd:c25:c25a:d00a:c63b
612c19:dd:d9:dd:c25:c25a:d00a:c63c/1282c19:dd:d9:dd:c25:c25a:d00a:c63c
622c19:dd:d9:dd:c25:c25a:d00a:c63d/1282c19:dd:d9:dd:c25:c25a:d00a:c63d
632c19:dd:d9:dd:c25:c25a:d00a:c63e/1282c19:dd:d9:dd:c25:c25a:d00a:c63e
642c19:dd:d9:dd:c25:c25a:d00a:c63f/1282c19:dd:d9:dd:c25:c25a:d00a:c63f
652c19:dd:d9:dd:c25:c25a:d00a:c640/1282c19:dd:d9:dd:c25:c25a:d00a:c640
662c19:dd:d9:dd:c25:c25a:d00a:c641/1282c19:dd:d9:dd:c25:c25a:d00a:c641
672c19:dd:d9:dd:c25:c25a:d00a:c642/1282c19:dd:d9:dd:c25:c25a:d00a:c642
682c19:dd:d9:dd:c25:c25a:d00a:c643/1282c19:dd:d9:dd:c25:c25a:d00a:c643
692c19:dd:d9:dd:c25:c25a:d00a:c644/1282c19:dd:d9:dd:c25:c25a:d00a:c644
702c19:dd:d9:dd:c25:c25a:d00a:c645/1282c19:dd:d9:dd:c25:c25a:d00a:c645
712c19:dd:d9:dd:c25:c25a:d00a:c646/1282c19:dd:d9:dd:c25:c25a:d00a:c646
722c19:dd:d9:dd:c25:c25a:d00a:c647/1282c19:dd:d9:dd:c25:c25a:d00a:c647
732c19:dd:d9:dd:c25:c25a:d00a:c648/1282c19:dd:d9:dd:c25:c25a:d00a:c648
742c19:dd:d9:dd:c25:c25a:d00a:c649/1282c19:dd:d9:dd:c25:c25a:d00a:c649
752c19:dd:d9:dd:c25:c25a:d00a:c64a/1282c19:dd:d9:dd:c25:c25a:d00a:c64a
762c19:dd:d9:dd:c25:c25a:d00a:c64b/1282c19:dd:d9:dd:c25:c25a:d00a:c64b
772c19:dd:d9:dd:c25:c25a:d00a:c64c/1282c19:dd:d9:dd:c25:c25a:d00a:c64c
782c19:dd:d9:dd:c25:c25a:d00a:c64d/1282c19:dd:d9:dd:c25:c25a:d00a:c64d
792c19:dd:d9:dd:c25:c25a:d00a:c64e/1282c19:dd:d9:dd:c25:c25a:d00a:c64e
802c19:dd:d9:dd:c25:c25a:d00a:c64f/1282c19:dd:d9:dd:c25:c25a:d00a:c64f
812c19:dd:d9:dd:c25:c25a:d00a:c650/1282c19:dd:d9:dd:c25:c25a:d00a:c650
822c19:dd:d9:dd:c25:c25a:d00a:c651/1282c19:dd:d9:dd:c25:c25a:d00a:c651
832c19:dd:d9:dd:c25:c25a:d00a:c652/1282c19:dd:d9:dd:c25:c25a:d00a:c652
842c19:dd:d9:dd:c25:c25a:d00a:c653/1282c19:dd:d9:dd:c25:c25a:d00a:c653
852c19:dd:d9:dd:c25:c25a:d00a:c654/1282c19:dd:d9:dd:c25:c25a:d00a:c654
862c19:dd:d9:dd:c25:c25a:d00a:c655/1282c19:dd:d9:dd:c25:c25a:d00a:c655
872c19:dd:d9:dd:c25:c25a:d00a:c656/1282c19:dd:d9:dd:c25:c25a:d00a:c656
882c19:dd:d9:dd:c25:c25a:d00a:c657/1282c19:dd:d9:dd:c25:c25a:d00a:c657
892c19:dd:d9:dd:c25:c25a:d00a:c658/1282c19:dd:d9:dd:c25:c25a:d00a:c658
902c19:dd:d9:dd:c25:c25a:d00a:c659/1282c19:dd:d9:dd:c25:c25a:d00a:c659
912c19:dd:d9:dd:c25:c25a:d00a:c65a/1282c19:dd:d9:dd:c25:c25a:d00a:c65a
922c19:dd:d9:dd:c25:c25a:d00a:c65b/1282c19:dd:d9:dd:c25:c25a:d00a:c65b
932c19:dd:d9:dd:c25:c25a:d00a:c65c/1282c19:dd:d9:dd:c25:c25a:d00a:c65c
942c19:dd:d9:dd:c25:c25a:d00a:c65d/1282c19:dd:d9:dd:c25:c25a:d00a:c65d
952c19:dd:d9:dd:c25:c25a:d00a:c65e/1282c19:dd:d9:dd:c25:c25a:d00a:c65e
962c19:dd:d9:dd:c25:c25a:d00a:c65f/1282c19:dd:d9:dd:c25:c25a:d00a:c65f
972c19:dd:d9:dd:c25:c25a:d00a:c660/1282c19:dd:d9:dd:c25:c25a:d00a:c660
982c19:dd:d9:dd:c25:c25a:d00a:c661/1282c19:dd:d9:dd:c25:c25a:d00a:c661
992c19:dd:d9:dd:c25:c25a:d00a:c662/1282c19:dd:d9:dd:c25:c25a:d00a:c662
1002c19:dd:d9:dd:c25:c25a:d00a:c663/1282c19:dd:d9:dd:c25:c25a:d00a:c663
1012c19:dd:d9:dd:c25:c25a:d00a:c664/1282c19:dd:d9:dd:c25:c25a:d00a:c664
1022c19:dd:d9:dd:c25:c25a:d00a:c665/1282c19:dd:d9:dd:c25:c25a:d00a:c665
1032c19:dd:d9:dd:c25:c25a:d00a:c666/1282c19:dd:d9:dd:c25:c25a:d00a:c666
1042c19:dd:d9:dd:c25:c25a:d00a:c667/1282c19:dd:d9:dd:c25:c25a:d00a:c667
1052c19:dd:d9:dd:c25:c25a:d00a:c668/1282c19:dd:d9:dd:c25:c25a:d00a:c668
1062c19:dd:d9:dd:c25:c25a:d00a:c669/1282c19:dd:d9:dd:c25:c25a:d00a:c669
1072c19:dd:d9:dd:c25:c25a:d00a:c66a/1282c19:dd:d9:dd:c25:c25a:d00a:c66a
1082c19:dd:d9:dd:c25:c25a:d00a:c66b/1282c19:dd:d9:dd:c25:c25a:d00a:c66b
1092c19:dd:d9:dd:c25:c25a:d00a:c66c/1282c19:dd:d9:dd:c25:c25a:d00a:c66c
1102c19:dd:d9:dd:c25:c25a:d00a:c66d/1282c19:dd:d9:dd:c25:c25a:d00a:c66d
1112c19:dd:d9:dd:c25:c25a:d00a:c66e/1282c19:dd:d9:dd:c25:c25a:d00a:c66e
1122c19:dd:d9:dd:c25:c25a:d00a:c66f/1282c19:dd:d9:dd:c25:c25a:d00a:c66f
1132c19:dd:d9:dd:c25:c25a:d00a:c670/1282c19:dd:d9:dd:c25:c25a:d00a:c670
1142c19:dd:d9:dd:c25:c25a:d00a:c671/1282c19:dd:d9:dd:c25:c25a:d00a:c671
1152c19:dd:d9:dd:c25:c25a:d00a:c672/1282c19:dd:d9:dd:c25:c25a:d00a:c672
1162c19:dd:d9:dd:c25:c25a:d00a:c673/1282c19:dd:d9:dd:c25:c25a:d00a:c673
1172c19:dd:d9:dd:c25:c25a:d00a:c674/1282c19:dd:d9:dd:c25:c25a:d00a:c674
1182c19:dd:d9:dd:c25:c25a:d00a:c675/1282c19:dd:d9:dd:c25:c25a:d00a:c675
1192c19:dd:d9:dd:c25:c25a:d00a:c676/1282c19:dd:d9:dd:c25:c25a:d00a:c676
1202c19:dd:d9:dd:c25:c25a:d00a:c677/1282c19:dd:d9:dd:c25:c25a:d00a:c677
1212c19:dd:d9:dd:c25:c25a:d00a:c678/1282c19:dd:d9:dd:c25:c25a:d00a:c678
1222c19:dd:d9:dd:c25:c25a:d00a:c679/1282c19:dd:d9:dd:c25:c25a:d00a:c679
1232c19:dd:d9:dd:c25:c25a:d00a:c67a/1282c19:dd:d9:dd:c25:c25a:d00a:c67a
1242c19:dd:d9:dd:c25:c25a:d00a:c67b/1282c19:dd:d9:dd:c25:c25a:d00a:c67b
1252c19:dd:d9:dd:c25:c25a:d00a:c67c/1282c19:dd:d9:dd:c25:c25a:d00a:c67c
1262c19:dd:d9:dd:c25:c25a:d00a:c67d/1282c19:dd:d9:dd:c25:c25a:d00a:c67d
1272c19:dd:d9:dd:c25:c25a:d00a:c67e/1282c19:dd:d9:dd:c25:c25a:d00a:c67e
1282c19:dd:d9:dd:c25:c25a:d00a:c67f/1282c19:dd:d9:dd:c25:c25a:d00a:c67f
1292c19:dd:d9:dd:c25:c25a:d00a:c680/1282c19:dd:d9:dd:c25:c25a:d00a:c680
1302c19:dd:d9:dd:c25:c25a:d00a:c681/1282c19:dd:d9:dd:c25:c25a:d00a:c681
1312c19:dd:d9:dd:c25:c25a:d00a:c682/1282c19:dd:d9:dd:c25:c25a:d00a:c682
1322c19:dd:d9:dd:c25:c25a:d00a:c683/1282c19:dd:d9:dd:c25:c25a:d00a:c683
1332c19:dd:d9:dd:c25:c25a:d00a:c684/1282c19:dd:d9:dd:c25:c25a:d00a:c684
1342c19:dd:d9:dd:c25:c25a:d00a:c685/1282c19:dd:d9:dd:c25:c25a:d00a:c685
1352c19:dd:d9:dd:c25:c25a:d00a:c686/1282c19:dd:d9:dd:c25:c25a:d00a:c686
1362c19:dd:d9:dd:c25:c25a:d00a:c687/1282c19:dd:d9:dd:c25:c25a:d00a:c687
1372c19:dd:d9:dd:c25:c25a:d00a:c688/1282c19:dd:d9:dd:c25:c25a:d00a:c688
1382c19:dd:d9:dd:c25:c25a:d00a:c689/1282c19:dd:d9:dd:c25:c25a:d00a:c689
1392c19:dd:d9:dd:c25:c25a:d00a:c68a/1282c19:dd:d9:dd:c25:c25a:d00a:c68a
1402c19:dd:d9:dd:c25:c25a:d00a:c68b/1282c19:dd:d9:dd:c25:c25a:d00a:c68b
1412c19:dd:d9:dd:c25:c25a:d00a:c68c/1282c19:dd:d9:dd:c25:c25a:d00a:c68c
1422c19:dd:d9:dd:c25:c25a:d00a:c68d/1282c19:dd:d9:dd:c25:c25a:d00a:c68d
1432c19:dd:d9:dd:c25:c25a:d00a:c68e/1282c19:dd:d9:dd:c25:c25a:d00a:c68e
1442c19:dd:d9:dd:c25:c25a:d00a:c68f/1282c19:dd:d9:dd:c25:c25a:d00a:c68f
1452c19:dd:d9:dd:c25:c25a:d00a:c690/1282c19:dd:d9:dd:c25:c25a:d00a:c690
1462c19:dd:d9:dd:c25:c25a:d00a:c691/1282c19:dd:d9:dd:c25:c25a:d00a:c691
1472c19:dd:d9:dd:c25:c25a:d00a:c692/1282c19:dd:d9:dd:c25:c25a:d00a:c692
1482c19:dd:d9:dd:c25:c25a:d00a:c693/1282c19:dd:d9:dd:c25:c25a:d00a:c693
1492c19:dd:d9:dd:c25:c25a:d00a:c694/1282c19:dd:d9:dd:c25:c25a:d00a:c694
1502c19:dd:d9:dd:c25:c25a:d00a:c695/1282c19:dd:d9:dd:c25:c25a:d00a:c695
1512c19:dd:d9:dd:c25:c25a:d00a:c696/1282c19:dd:d9:dd:c25:c25a:d00a:c696
1522c19:dd:d9:dd:c25:c25a:d00a:c697/1282c19:dd:d9:dd:c25:c25a:d00a:c697
1532c19:dd:d9:dd:c25:c25a:d00a:c698/1282c19:dd:d9:dd:c25:c25a:d00a:c698
1542c19:dd:d9:dd:c25:c25a:d00a:c699/1282c19:dd:d9:dd:c25:c25a:d00a:c699
1552c19:dd:d9:dd:c25:c25a:d00a:c69a/1282c19:dd:d9:dd:c25:c25a:d00a:c69a
1562c19:dd:d9:dd:c25:c25a:d00a:c69b/1282c19:dd:d9:dd:c25:c25a:d00a:c69b
1572c19:dd:d9:dd:c25:c25a:d00a:c69c/1282c19:dd:d9:dd:c25:c25a:d00a:c69c
1582c19:dd:d9:dd:c25:c25a:d00a:c69d/1282c19:dd:d9:dd:c25:c25a:d00a:c69d
1592c19:dd:d9:dd:c25:c25a:d00a:c69e/1282c19:dd:d9:dd:c25:c25a:d00a:c69e
1602c19:dd:d9:dd:c25:c25a:d00a:c69f/1282c19:dd:d9:dd:c25:c25a:d00a:c69f
1612c19:dd:d9:dd:c25:c25a:d00a:c6a0/1282c19:dd:d9:dd:c25:c25a:d00a:c6a0
1622c19:dd:d9:dd:c25:c25a:d00a:c6a1/1282c19:dd:d9:dd:c25:c25a:d00a:c6a1
1632c19:dd:d9:dd:c25:c25a:d00a:c6a2/1282c19:dd:d9:dd:c25:c25a:d00a:c6a2
1642c19:dd:d9:dd:c25:c25a:d00a:c6a3/1282c19:dd:d9:dd:c25:c25a:d00a:c6a3
1652c19:dd:d9:dd:c25:c25a:d00a:c6a4/1282c19:dd:d9:dd:c25:c25a:d00a:c6a4
1662c19:dd:d9:dd:c25:c25a:d00a:c6a5/1282c19:dd:d9:dd:c25:c25a:d00a:c6a5
1672c19:dd:d9:dd:c25:c25a:d00a:c6a6/1282c19:dd:d9:dd:c25:c25a:d00a:c6a6
1682c19:dd:d9:dd:c25:c25a:d00a:c6a7/1282c19:dd:d9:dd:c25:c25a:d00a:c6a7
1692c19:dd:d9:dd:c25:c25a:d00a:c6a8/1282c19:dd:d9:dd:c25:c25a:d00a:c6a8
1702c19:dd:d9:dd:c25:c25a:d00a:c6a9/1282c19:dd:d9:dd:c25:c25a:d00a:c6a9
1712c19:dd:d9:dd:c25:c25a:d00a:c6aa/1282c19:dd:d9:dd:c25:c25a:d00a:c6aa
1722c19:dd:d9:dd:c25:c25a:d00a:c6ab/1282c19:dd:d9:dd:c25:c25a:d00a:c6ab
1732c19:dd:d9:dd:c25:c25a:d00a:c6ac/1282c19:dd:d9:dd:c25:c25a:d00a:c6ac
1742c19:dd:d9:dd:c25:c25a:d00a:c6ad/1282c19:dd:d9:dd:c25:c25a:d00a:c6ad
1752c19:dd:d9:dd:c25:c25a:d00a:c6ae/1282c19:dd:d9:dd:c25:c25a:d00a:c6ae
1762c19:dd:d9:dd:c25:c25a:d00a:c6af/1282c19:dd:d9:dd:c25:c25a:d00a:c6af
1772c19:dd:d9:dd:c25:c25a:d00a:c6b0/1282c19:dd:d9:dd:c25:c25a:d00a:c6b0
1782c19:dd:d9:dd:c25:c25a:d00a:c6b1/1282c19:dd:d9:dd:c25:c25a:d00a:c6b1
1792c19:dd:d9:dd:c25:c25a:d00a:c6b2/1282c19:dd:d9:dd:c25:c25a:d00a:c6b2
1802c19:dd:d9:dd:c25:c25a:d00a:c6b3/1282c19:dd:d9:dd:c25:c25a:d00a:c6b3
1812c19:dd:d9:dd:c25:c25a:d00a:c6b4/1282c19:dd:d9:dd:c25:c25a:d00a:c6b4
1822c19:dd:d9:dd:c25:c25a:d00a:c6b5/1282c19:dd:d9:dd:c25:c25a:d00a:c6b5
1832c19:dd:d9:dd:c25:c25a:d00a:c6b6/1282c19:dd:d9:dd:c25:c25a:d00a:c6b6
1842c19:dd:d9:dd:c25:c25a:d00a:c6b7/1282c19:dd:d9:dd:c25:c25a:d00a:c6b7
1852c19:dd:d9:dd:c25:c25a:d00a:c6b8/1282c19:dd:d9:dd:c25:c25a:d00a:c6b8
1862c19:dd:d9:dd:c25:c25a:d00a:c6b9/1282c19:dd:d9:dd:c25:c25a:d00a:c6b9
1872c19:dd:d9:dd:c25:c25a:d00a:c6ba/1282c19:dd:d9:dd:c25:c25a:d00a:c6ba
1882c19:dd:d9:dd:c25:c25a:d00a:c6bb/1282c19:dd:d9:dd:c25:c25a:d00a:c6bb
1892c19:dd:d9:dd:c25:c25a:d00a:c6bc/1282c19:dd:d9:dd:c25:c25a:d00a:c6bc
1902c19:dd:d9:dd:c25:c25a:d00a:c6bd/1282c19:dd:d9:dd:c25:c25a:d00a:c6bd
1912c19:dd:d9:dd:c25:c25a:d00a:c6be/1282c19:dd:d9:dd:c25:c25a:d00a:c6be
1922c19:dd:d9:dd:c25:c25a:d00a:c6bf/1282c19:dd:d9:dd:c25:c25a:d00a:c6bf
1932c19:dd:d9:dd:c25:c25a:d00a:c6c0/1282c19:dd:d9:dd:c25:c25a:d00a:c6c0
1942c19:dd:d9:dd:c25:c25a:d00a:c6c1/1282c19:dd:d9:dd:c25:c25a:d00a:c6c1
1952c19:dd:d9:dd:c25:c25a:d00a:c6c2/1282c19:dd:d9:dd:c25:c25a:d00a:c6c2
1962c19:dd:d9:dd:c25:c25a:d00a:c6c3/1282c19:dd:d9:dd:c25:c25a:d00a:c6c3
1972c19:dd:d9:dd:c25:c25a:d00a:c6c4/1282c19:dd:d9:dd:c25:c25a:d00a:c6c4
1982c19:dd:d9:dd:c25:c25a:d00a:c6c5/1282c19:dd:d9:dd:c25:c25a:d00a:c6c5
1992c19:dd:d9:dd:c25:c25a:d00a:c6c6/1282c19:dd:d9:dd:c25:c25a:d00a:c6c6
2002c19:dd:d9:dd:c25:c25a:d00a:c6c7/1282c19:dd:d9:dd:c25:c25a:d00a:c6c7
2012c19:dd:d9:dd:c25:c25a:d00a:c6c8/1282c19:dd:d9:dd:c25:c25a:d00a:c6c8
2022c19:dd:d9:dd:c25:c25a:d00a:c6c9/1282c19:dd:d9:dd:c25:c25a:d00a:c6c9
2032c19:dd:d9:dd:c25:c25a:d00a:c6ca/1282c19:dd:d9:dd:c25:c25a:d00a:c6ca
2042c19:dd:d9:dd:c25:c25a:d00a:c6cb/1282c19:dd:d9:dd:c25:c25a:d00a:c6cb
2052c19:dd:d9:dd:c25:c25a:d00a:c6cc/1282c19:dd:d9:dd:c25:c25a:d00a:c6cc
2062c19:dd:d9:dd:c25:c25a:d00a:c6cd/1282c19:dd:d9:dd:c25:c25a:d00a:c6cd
2072c19:dd:d9:dd:c25:c25a:d00a:c6ce/1282c19:dd:d9:dd:c25:c25a:d00a:c6ce
2082c19:dd:d9:dd:c25:c25a:d00a:c6cf/1282c19:dd:d9:dd:c25:c25a:d00a:c6cf
2092c19:dd:d9:dd:c25:c25a:d00a:c6d0/1282c19:dd:d9:dd:c25:c25a:d00a:c6d0
2102c19:dd:d9:dd:c25:c25a:d00a:c6d1/1282c19:dd:d9:dd:c25:c25a:d00a:c6d1
2112c19:dd:d9:dd:c25:c25a:d00a:c6d2/1282c19:dd:d9:dd:c25:c25a:d00a:c6d2
2122c19:dd:d9:dd:c25:c25a:d00a:c6d3/1282c19:dd:d9:dd:c25:c25a:d00a:c6d3
2132c19:dd:d9:dd:c25:c25a:d00a:c6d4/1282c19:dd:d9:dd:c25:c25a:d00a:c6d4
2142c19:dd:d9:dd:c25:c25a:d00a:c6d5/1282c19:dd:d9:dd:c25:c25a:d00a:c6d5
2152c19:dd:d9:dd:c25:c25a:d00a:c6d6/1282c19:dd:d9:dd:c25:c25a:d00a:c6d6
2162c19:dd:d9:dd:c25:c25a:d00a:c6d7/1282c19:dd:d9:dd:c25:c25a:d00a:c6d7
2172c19:dd:d9:dd:c25:c25a:d00a:c6d8/1282c19:dd:d9:dd:c25:c25a:d00a:c6d8
2182c19:dd:d9:dd:c25:c25a:d00a:c6d9/1282c19:dd:d9:dd:c25:c25a:d00a:c6d9
2192c19:dd:d9:dd:c25:c25a:d00a:c6da/1282c19:dd:d9:dd:c25:c25a:d00a:c6da
2202c19:dd:d9:dd:c25:c25a:d00a:c6db/1282c19:dd:d9:dd:c25:c25a:d00a:c6db
2212c19:dd:d9:dd:c25:c25a:d00a:c6dc/1282c19:dd:d9:dd:c25:c25a:d00a:c6dc
2222c19:dd:d9:dd:c25:c25a:d00a:c6dd/1282c19:dd:d9:dd:c25:c25a:d00a:c6dd
2232c19:dd:d9:dd:c25:c25a:d00a:c6de/1282c19:dd:d9:dd:c25:c25a:d00a:c6de
2242c19:dd:d9:dd:c25:c25a:d00a:c6df/1282c19:dd:d9:dd:c25:c25a:d00a:c6df
2252c19:dd:d9:dd:c25:c25a:d00a:c6e0/1282c19:dd:d9:dd:c25:c25a:d00a:c6e0
2262c19:dd:d9:dd:c25:c25a:d00a:c6e1/1282c19:dd:d9:dd:c25:c25a:d00a:c6e1
2272c19:dd:d9:dd:c25:c25a:d00a:c6e2/1282c19:dd:d9:dd:c25:c25a:d00a:c6e2
2282c19:dd:d9:dd:c25:c25a:d00a:c6e3/1282c19:dd:d9:dd:c25:c25a:d00a:c6e3
2292c19:dd:d9:dd:c25:c25a:d00a:c6e4/1282c19:dd:d9:dd:c25:c25a:d00a:c6e4
2302c19:dd:d9:dd:c25:c25a:d00a:c6e5/1282c19:dd:d9:dd:c25:c25a:d00a:c6e5
2312c19:dd:d9:dd:c25:c25a:d00a:c6e6/1282c19:dd:d9:dd:c25:c25a:d00a:c6e6
2322c19:dd:d9:dd:c25:c25a:d00a:c6e7/1282c19:dd:d9:dd:c25:c25a:d00a:c6e7
2332c19:dd:d9:dd:c25:c25a:d00a:c6e8/1282c19:dd:d9:dd:c25:c25a:d00a:c6e8
2342c19:dd:d9:dd:c25:c25a:d00a:c6e9/1282c19:dd:d9:dd:c25:c25a:d00a:c6e9
2352c19:dd:d9:dd:c25:c25a:d00a:c6ea/1282c19:dd:d9:dd:c25:c25a:d00a:c6ea
2362c19:dd:d9:dd:c25:c25a:d00a:c6eb/1282c19:dd:d9:dd:c25:c25a:d00a:c6eb
2372c19:dd:d9:dd:c25:c25a:d00a:c6ec/1282c19:dd:d9:dd:c25:c25a:d00a:c6ec
2382c19:dd:d9:dd:c25:c25a:d00a:c6ed/1282c19:dd:d9:dd:c25:c25a:d00a:c6ed
2392c19:dd:d9:dd:c25:c25a:d00a:c6ee/1282c19:dd:d9:dd:c25:c25a:d00a:c6ee
2402c19:dd:d9:dd:c25:c25a:d00a:c6ef/1282c19:dd:d9:dd:c25:c25a:d00a:c6ef
2412c19:dd:d9:dd:c25:c25a:d00a:c6f0/1282c19:dd:d9:dd:c25:c25a:d00a:c6f0
2422c19:dd:d9:dd:c25:c25a:d00a:c6f1/1282c19:dd:d9:dd:c25:c25a:d00a:c6f1
2432c19:dd:d9:dd:c25:c25a:d00a:c6f2/1282c19:dd:d9:dd:c25:c25a:d00a:c6f2
2442c19:dd:d9:dd:c25:c25a:d00a:c6f3/1282c19:dd:d9:dd:c25:c25a:d00a:c6f3
2452c19:dd:d9:dd:c25:c25a:d00a:c6f4/1282c19:dd:d9:dd:c25:c25a:d00a:c6f4
2462c19:dd:d9:dd:c25:c25a:d00a:c6f5/1282c19:dd:d9:dd:c25:c25a:d00a:c6f5
2472c19:dd:d9:dd:c25:c25a:d00a:c6f6/1282c19:dd:d9:dd:c25:c25a:d00a:c6f6
2482c19:dd:d9:dd:c25:c25a:d00a:c6f7/1282c19:dd:d9:dd:c25:c25a:d00a:c6f7
2492c19:dd:d9:dd:c25:c25a:d00a:c6f8/1282c19:dd:d9:dd:c25:c25a:d00a:c6f8
2502c19:dd:d9:dd:c25:c25a:d00a:c6f9/1282c19:dd:d9:dd:c25:c25a:d00a:c6f9
2512c19:dd:d9:dd:c25:c25a:d00a:c6fa/1282c19:dd:d9:dd:c25:c25a:d00a:c6fa
2522c19:dd:d9:dd:c25:c25a:d00a:c6fb/1282c19:dd:d9:dd:c25:c25a:d00a:c6fb
2532c19:dd:d9:dd:c25:c25a:d00a:c6fc/1282c19:dd:d9:dd:c25:c25a:d00a:c6fc
2542c19:dd:d9:dd:c25:c25a:d00a:c6fd/1282c19:dd:d9:dd:c25:c25a:d00a:c6fd
2552c19:dd:d9:dd:c25:c25a:d00a:c6fe/1282c19:dd:d9:dd:c25:c25a:d00a:c6fe
2562c19:dd:d9:dd:c25:c25a:d00a:c6ff/1282c19:dd:d9:dd:c25:c25a:d00a:c6ff

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.