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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:ec00:c25:c25e:dd:dd4e:c600/119
First address
2c19:dd:ec00:c25:c25e:dd:dd4e:c600
Last address
2c19:dd:ec00:c25:c25e:dd:dd4e:c7ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:ec00:0c25:c25e:00dd:dd4e:c600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
6.c.e.4.d.d.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
7.c.e.4.d.d.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
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:ec00:c25:c25e:dd:dd4e:c600/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:ec00:c25:c25e:dd:dd4e:c600/1272c19:dd:ec00:c25:c25e:dd:dd4e:c601
22c19:dd:ec00:c25:c25e:dd:dd4e:c602/1272c19:dd:ec00:c25:c25e:dd:dd4e:c603
32c19:dd:ec00:c25:c25e:dd:dd4e:c604/1272c19:dd:ec00:c25:c25e:dd:dd4e:c605
42c19:dd:ec00:c25:c25e:dd:dd4e:c606/1272c19:dd:ec00:c25:c25e:dd:dd4e:c607
52c19:dd:ec00:c25:c25e:dd:dd4e:c608/1272c19:dd:ec00:c25:c25e:dd:dd4e:c609
62c19:dd:ec00:c25:c25e:dd:dd4e:c60a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c60b
72c19:dd:ec00:c25:c25e:dd:dd4e:c60c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c60d
82c19:dd:ec00:c25:c25e:dd:dd4e:c60e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c60f
92c19:dd:ec00:c25:c25e:dd:dd4e:c610/1272c19:dd:ec00:c25:c25e:dd:dd4e:c611
102c19:dd:ec00:c25:c25e:dd:dd4e:c612/1272c19:dd:ec00:c25:c25e:dd:dd4e:c613
112c19:dd:ec00:c25:c25e:dd:dd4e:c614/1272c19:dd:ec00:c25:c25e:dd:dd4e:c615
122c19:dd:ec00:c25:c25e:dd:dd4e:c616/1272c19:dd:ec00:c25:c25e:dd:dd4e:c617
132c19:dd:ec00:c25:c25e:dd:dd4e:c618/1272c19:dd:ec00:c25:c25e:dd:dd4e:c619
142c19:dd:ec00:c25:c25e:dd:dd4e:c61a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c61b
152c19:dd:ec00:c25:c25e:dd:dd4e:c61c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c61d
162c19:dd:ec00:c25:c25e:dd:dd4e:c61e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c61f
172c19:dd:ec00:c25:c25e:dd:dd4e:c620/1272c19:dd:ec00:c25:c25e:dd:dd4e:c621
182c19:dd:ec00:c25:c25e:dd:dd4e:c622/1272c19:dd:ec00:c25:c25e:dd:dd4e:c623
192c19:dd:ec00:c25:c25e:dd:dd4e:c624/1272c19:dd:ec00:c25:c25e:dd:dd4e:c625
202c19:dd:ec00:c25:c25e:dd:dd4e:c626/1272c19:dd:ec00:c25:c25e:dd:dd4e:c627
212c19:dd:ec00:c25:c25e:dd:dd4e:c628/1272c19:dd:ec00:c25:c25e:dd:dd4e:c629
222c19:dd:ec00:c25:c25e:dd:dd4e:c62a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c62b
232c19:dd:ec00:c25:c25e:dd:dd4e:c62c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c62d
242c19:dd:ec00:c25:c25e:dd:dd4e:c62e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c62f
252c19:dd:ec00:c25:c25e:dd:dd4e:c630/1272c19:dd:ec00:c25:c25e:dd:dd4e:c631
262c19:dd:ec00:c25:c25e:dd:dd4e:c632/1272c19:dd:ec00:c25:c25e:dd:dd4e:c633
272c19:dd:ec00:c25:c25e:dd:dd4e:c634/1272c19:dd:ec00:c25:c25e:dd:dd4e:c635
282c19:dd:ec00:c25:c25e:dd:dd4e:c636/1272c19:dd:ec00:c25:c25e:dd:dd4e:c637
292c19:dd:ec00:c25:c25e:dd:dd4e:c638/1272c19:dd:ec00:c25:c25e:dd:dd4e:c639
302c19:dd:ec00:c25:c25e:dd:dd4e:c63a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c63b
312c19:dd:ec00:c25:c25e:dd:dd4e:c63c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c63d
322c19:dd:ec00:c25:c25e:dd:dd4e:c63e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c63f
332c19:dd:ec00:c25:c25e:dd:dd4e:c640/1272c19:dd:ec00:c25:c25e:dd:dd4e:c641
342c19:dd:ec00:c25:c25e:dd:dd4e:c642/1272c19:dd:ec00:c25:c25e:dd:dd4e:c643
352c19:dd:ec00:c25:c25e:dd:dd4e:c644/1272c19:dd:ec00:c25:c25e:dd:dd4e:c645
362c19:dd:ec00:c25:c25e:dd:dd4e:c646/1272c19:dd:ec00:c25:c25e:dd:dd4e:c647
372c19:dd:ec00:c25:c25e:dd:dd4e:c648/1272c19:dd:ec00:c25:c25e:dd:dd4e:c649
382c19:dd:ec00:c25:c25e:dd:dd4e:c64a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c64b
392c19:dd:ec00:c25:c25e:dd:dd4e:c64c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c64d
402c19:dd:ec00:c25:c25e:dd:dd4e:c64e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c64f
412c19:dd:ec00:c25:c25e:dd:dd4e:c650/1272c19:dd:ec00:c25:c25e:dd:dd4e:c651
422c19:dd:ec00:c25:c25e:dd:dd4e:c652/1272c19:dd:ec00:c25:c25e:dd:dd4e:c653
432c19:dd:ec00:c25:c25e:dd:dd4e:c654/1272c19:dd:ec00:c25:c25e:dd:dd4e:c655
442c19:dd:ec00:c25:c25e:dd:dd4e:c656/1272c19:dd:ec00:c25:c25e:dd:dd4e:c657
452c19:dd:ec00:c25:c25e:dd:dd4e:c658/1272c19:dd:ec00:c25:c25e:dd:dd4e:c659
462c19:dd:ec00:c25:c25e:dd:dd4e:c65a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c65b
472c19:dd:ec00:c25:c25e:dd:dd4e:c65c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c65d
482c19:dd:ec00:c25:c25e:dd:dd4e:c65e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c65f
492c19:dd:ec00:c25:c25e:dd:dd4e:c660/1272c19:dd:ec00:c25:c25e:dd:dd4e:c661
502c19:dd:ec00:c25:c25e:dd:dd4e:c662/1272c19:dd:ec00:c25:c25e:dd:dd4e:c663
512c19:dd:ec00:c25:c25e:dd:dd4e:c664/1272c19:dd:ec00:c25:c25e:dd:dd4e:c665
522c19:dd:ec00:c25:c25e:dd:dd4e:c666/1272c19:dd:ec00:c25:c25e:dd:dd4e:c667
532c19:dd:ec00:c25:c25e:dd:dd4e:c668/1272c19:dd:ec00:c25:c25e:dd:dd4e:c669
542c19:dd:ec00:c25:c25e:dd:dd4e:c66a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c66b
552c19:dd:ec00:c25:c25e:dd:dd4e:c66c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c66d
562c19:dd:ec00:c25:c25e:dd:dd4e:c66e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c66f
572c19:dd:ec00:c25:c25e:dd:dd4e:c670/1272c19:dd:ec00:c25:c25e:dd:dd4e:c671
582c19:dd:ec00:c25:c25e:dd:dd4e:c672/1272c19:dd:ec00:c25:c25e:dd:dd4e:c673
592c19:dd:ec00:c25:c25e:dd:dd4e:c674/1272c19:dd:ec00:c25:c25e:dd:dd4e:c675
602c19:dd:ec00:c25:c25e:dd:dd4e:c676/1272c19:dd:ec00:c25:c25e:dd:dd4e:c677
612c19:dd:ec00:c25:c25e:dd:dd4e:c678/1272c19:dd:ec00:c25:c25e:dd:dd4e:c679
622c19:dd:ec00:c25:c25e:dd:dd4e:c67a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c67b
632c19:dd:ec00:c25:c25e:dd:dd4e:c67c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c67d
642c19:dd:ec00:c25:c25e:dd:dd4e:c67e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c67f
652c19:dd:ec00:c25:c25e:dd:dd4e:c680/1272c19:dd:ec00:c25:c25e:dd:dd4e:c681
662c19:dd:ec00:c25:c25e:dd:dd4e:c682/1272c19:dd:ec00:c25:c25e:dd:dd4e:c683
672c19:dd:ec00:c25:c25e:dd:dd4e:c684/1272c19:dd:ec00:c25:c25e:dd:dd4e:c685
682c19:dd:ec00:c25:c25e:dd:dd4e:c686/1272c19:dd:ec00:c25:c25e:dd:dd4e:c687
692c19:dd:ec00:c25:c25e:dd:dd4e:c688/1272c19:dd:ec00:c25:c25e:dd:dd4e:c689
702c19:dd:ec00:c25:c25e:dd:dd4e:c68a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c68b
712c19:dd:ec00:c25:c25e:dd:dd4e:c68c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c68d
722c19:dd:ec00:c25:c25e:dd:dd4e:c68e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c68f
732c19:dd:ec00:c25:c25e:dd:dd4e:c690/1272c19:dd:ec00:c25:c25e:dd:dd4e:c691
742c19:dd:ec00:c25:c25e:dd:dd4e:c692/1272c19:dd:ec00:c25:c25e:dd:dd4e:c693
752c19:dd:ec00:c25:c25e:dd:dd4e:c694/1272c19:dd:ec00:c25:c25e:dd:dd4e:c695
762c19:dd:ec00:c25:c25e:dd:dd4e:c696/1272c19:dd:ec00:c25:c25e:dd:dd4e:c697
772c19:dd:ec00:c25:c25e:dd:dd4e:c698/1272c19:dd:ec00:c25:c25e:dd:dd4e:c699
782c19:dd:ec00:c25:c25e:dd:dd4e:c69a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c69b
792c19:dd:ec00:c25:c25e:dd:dd4e:c69c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c69d
802c19:dd:ec00:c25:c25e:dd:dd4e:c69e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c69f
812c19:dd:ec00:c25:c25e:dd:dd4e:c6a0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6a1
822c19:dd:ec00:c25:c25e:dd:dd4e:c6a2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6a3
832c19:dd:ec00:c25:c25e:dd:dd4e:c6a4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6a5
842c19:dd:ec00:c25:c25e:dd:dd4e:c6a6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6a7
852c19:dd:ec00:c25:c25e:dd:dd4e:c6a8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6a9
862c19:dd:ec00:c25:c25e:dd:dd4e:c6aa/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6ab
872c19:dd:ec00:c25:c25e:dd:dd4e:c6ac/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6ad
882c19:dd:ec00:c25:c25e:dd:dd4e:c6ae/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6af
892c19:dd:ec00:c25:c25e:dd:dd4e:c6b0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6b1
902c19:dd:ec00:c25:c25e:dd:dd4e:c6b2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6b3
912c19:dd:ec00:c25:c25e:dd:dd4e:c6b4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6b5
922c19:dd:ec00:c25:c25e:dd:dd4e:c6b6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6b7
932c19:dd:ec00:c25:c25e:dd:dd4e:c6b8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6b9
942c19:dd:ec00:c25:c25e:dd:dd4e:c6ba/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6bb
952c19:dd:ec00:c25:c25e:dd:dd4e:c6bc/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6bd
962c19:dd:ec00:c25:c25e:dd:dd4e:c6be/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6bf
972c19:dd:ec00:c25:c25e:dd:dd4e:c6c0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6c1
982c19:dd:ec00:c25:c25e:dd:dd4e:c6c2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6c3
992c19:dd:ec00:c25:c25e:dd:dd4e:c6c4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6c5
1002c19:dd:ec00:c25:c25e:dd:dd4e:c6c6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6c7
1012c19:dd:ec00:c25:c25e:dd:dd4e:c6c8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6c9
1022c19:dd:ec00:c25:c25e:dd:dd4e:c6ca/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6cb
1032c19:dd:ec00:c25:c25e:dd:dd4e:c6cc/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6cd
1042c19:dd:ec00:c25:c25e:dd:dd4e:c6ce/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6cf
1052c19:dd:ec00:c25:c25e:dd:dd4e:c6d0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6d1
1062c19:dd:ec00:c25:c25e:dd:dd4e:c6d2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6d3
1072c19:dd:ec00:c25:c25e:dd:dd4e:c6d4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6d5
1082c19:dd:ec00:c25:c25e:dd:dd4e:c6d6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6d7
1092c19:dd:ec00:c25:c25e:dd:dd4e:c6d8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6d9
1102c19:dd:ec00:c25:c25e:dd:dd4e:c6da/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6db
1112c19:dd:ec00:c25:c25e:dd:dd4e:c6dc/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6dd
1122c19:dd:ec00:c25:c25e:dd:dd4e:c6de/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6df
1132c19:dd:ec00:c25:c25e:dd:dd4e:c6e0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6e1
1142c19:dd:ec00:c25:c25e:dd:dd4e:c6e2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6e3
1152c19:dd:ec00:c25:c25e:dd:dd4e:c6e4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6e5
1162c19:dd:ec00:c25:c25e:dd:dd4e:c6e6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6e7
1172c19:dd:ec00:c25:c25e:dd:dd4e:c6e8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6e9
1182c19:dd:ec00:c25:c25e:dd:dd4e:c6ea/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6eb
1192c19:dd:ec00:c25:c25e:dd:dd4e:c6ec/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6ed
1202c19:dd:ec00:c25:c25e:dd:dd4e:c6ee/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6ef
1212c19:dd:ec00:c25:c25e:dd:dd4e:c6f0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6f1
1222c19:dd:ec00:c25:c25e:dd:dd4e:c6f2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6f3
1232c19:dd:ec00:c25:c25e:dd:dd4e:c6f4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6f5
1242c19:dd:ec00:c25:c25e:dd:dd4e:c6f6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6f7
1252c19:dd:ec00:c25:c25e:dd:dd4e:c6f8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6f9
1262c19:dd:ec00:c25:c25e:dd:dd4e:c6fa/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6fb
1272c19:dd:ec00:c25:c25e:dd:dd4e:c6fc/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6fd
1282c19:dd:ec00:c25:c25e:dd:dd4e:c6fe/1272c19:dd:ec00:c25:c25e:dd:dd4e:c6ff
1292c19:dd:ec00:c25:c25e:dd:dd4e:c700/1272c19:dd:ec00:c25:c25e:dd:dd4e:c701
1302c19:dd:ec00:c25:c25e:dd:dd4e:c702/1272c19:dd:ec00:c25:c25e:dd:dd4e:c703
1312c19:dd:ec00:c25:c25e:dd:dd4e:c704/1272c19:dd:ec00:c25:c25e:dd:dd4e:c705
1322c19:dd:ec00:c25:c25e:dd:dd4e:c706/1272c19:dd:ec00:c25:c25e:dd:dd4e:c707
1332c19:dd:ec00:c25:c25e:dd:dd4e:c708/1272c19:dd:ec00:c25:c25e:dd:dd4e:c709
1342c19:dd:ec00:c25:c25e:dd:dd4e:c70a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c70b
1352c19:dd:ec00:c25:c25e:dd:dd4e:c70c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c70d
1362c19:dd:ec00:c25:c25e:dd:dd4e:c70e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c70f
1372c19:dd:ec00:c25:c25e:dd:dd4e:c710/1272c19:dd:ec00:c25:c25e:dd:dd4e:c711
1382c19:dd:ec00:c25:c25e:dd:dd4e:c712/1272c19:dd:ec00:c25:c25e:dd:dd4e:c713
1392c19:dd:ec00:c25:c25e:dd:dd4e:c714/1272c19:dd:ec00:c25:c25e:dd:dd4e:c715
1402c19:dd:ec00:c25:c25e:dd:dd4e:c716/1272c19:dd:ec00:c25:c25e:dd:dd4e:c717
1412c19:dd:ec00:c25:c25e:dd:dd4e:c718/1272c19:dd:ec00:c25:c25e:dd:dd4e:c719
1422c19:dd:ec00:c25:c25e:dd:dd4e:c71a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c71b
1432c19:dd:ec00:c25:c25e:dd:dd4e:c71c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c71d
1442c19:dd:ec00:c25:c25e:dd:dd4e:c71e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c71f
1452c19:dd:ec00:c25:c25e:dd:dd4e:c720/1272c19:dd:ec00:c25:c25e:dd:dd4e:c721
1462c19:dd:ec00:c25:c25e:dd:dd4e:c722/1272c19:dd:ec00:c25:c25e:dd:dd4e:c723
1472c19:dd:ec00:c25:c25e:dd:dd4e:c724/1272c19:dd:ec00:c25:c25e:dd:dd4e:c725
1482c19:dd:ec00:c25:c25e:dd:dd4e:c726/1272c19:dd:ec00:c25:c25e:dd:dd4e:c727
1492c19:dd:ec00:c25:c25e:dd:dd4e:c728/1272c19:dd:ec00:c25:c25e:dd:dd4e:c729
1502c19:dd:ec00:c25:c25e:dd:dd4e:c72a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c72b
1512c19:dd:ec00:c25:c25e:dd:dd4e:c72c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c72d
1522c19:dd:ec00:c25:c25e:dd:dd4e:c72e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c72f
1532c19:dd:ec00:c25:c25e:dd:dd4e:c730/1272c19:dd:ec00:c25:c25e:dd:dd4e:c731
1542c19:dd:ec00:c25:c25e:dd:dd4e:c732/1272c19:dd:ec00:c25:c25e:dd:dd4e:c733
1552c19:dd:ec00:c25:c25e:dd:dd4e:c734/1272c19:dd:ec00:c25:c25e:dd:dd4e:c735
1562c19:dd:ec00:c25:c25e:dd:dd4e:c736/1272c19:dd:ec00:c25:c25e:dd:dd4e:c737
1572c19:dd:ec00:c25:c25e:dd:dd4e:c738/1272c19:dd:ec00:c25:c25e:dd:dd4e:c739
1582c19:dd:ec00:c25:c25e:dd:dd4e:c73a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c73b
1592c19:dd:ec00:c25:c25e:dd:dd4e:c73c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c73d
1602c19:dd:ec00:c25:c25e:dd:dd4e:c73e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c73f
1612c19:dd:ec00:c25:c25e:dd:dd4e:c740/1272c19:dd:ec00:c25:c25e:dd:dd4e:c741
1622c19:dd:ec00:c25:c25e:dd:dd4e:c742/1272c19:dd:ec00:c25:c25e:dd:dd4e:c743
1632c19:dd:ec00:c25:c25e:dd:dd4e:c744/1272c19:dd:ec00:c25:c25e:dd:dd4e:c745
1642c19:dd:ec00:c25:c25e:dd:dd4e:c746/1272c19:dd:ec00:c25:c25e:dd:dd4e:c747
1652c19:dd:ec00:c25:c25e:dd:dd4e:c748/1272c19:dd:ec00:c25:c25e:dd:dd4e:c749
1662c19:dd:ec00:c25:c25e:dd:dd4e:c74a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c74b
1672c19:dd:ec00:c25:c25e:dd:dd4e:c74c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c74d
1682c19:dd:ec00:c25:c25e:dd:dd4e:c74e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c74f
1692c19:dd:ec00:c25:c25e:dd:dd4e:c750/1272c19:dd:ec00:c25:c25e:dd:dd4e:c751
1702c19:dd:ec00:c25:c25e:dd:dd4e:c752/1272c19:dd:ec00:c25:c25e:dd:dd4e:c753
1712c19:dd:ec00:c25:c25e:dd:dd4e:c754/1272c19:dd:ec00:c25:c25e:dd:dd4e:c755
1722c19:dd:ec00:c25:c25e:dd:dd4e:c756/1272c19:dd:ec00:c25:c25e:dd:dd4e:c757
1732c19:dd:ec00:c25:c25e:dd:dd4e:c758/1272c19:dd:ec00:c25:c25e:dd:dd4e:c759
1742c19:dd:ec00:c25:c25e:dd:dd4e:c75a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c75b
1752c19:dd:ec00:c25:c25e:dd:dd4e:c75c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c75d
1762c19:dd:ec00:c25:c25e:dd:dd4e:c75e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c75f
1772c19:dd:ec00:c25:c25e:dd:dd4e:c760/1272c19:dd:ec00:c25:c25e:dd:dd4e:c761
1782c19:dd:ec00:c25:c25e:dd:dd4e:c762/1272c19:dd:ec00:c25:c25e:dd:dd4e:c763
1792c19:dd:ec00:c25:c25e:dd:dd4e:c764/1272c19:dd:ec00:c25:c25e:dd:dd4e:c765
1802c19:dd:ec00:c25:c25e:dd:dd4e:c766/1272c19:dd:ec00:c25:c25e:dd:dd4e:c767
1812c19:dd:ec00:c25:c25e:dd:dd4e:c768/1272c19:dd:ec00:c25:c25e:dd:dd4e:c769
1822c19:dd:ec00:c25:c25e:dd:dd4e:c76a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c76b
1832c19:dd:ec00:c25:c25e:dd:dd4e:c76c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c76d
1842c19:dd:ec00:c25:c25e:dd:dd4e:c76e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c76f
1852c19:dd:ec00:c25:c25e:dd:dd4e:c770/1272c19:dd:ec00:c25:c25e:dd:dd4e:c771
1862c19:dd:ec00:c25:c25e:dd:dd4e:c772/1272c19:dd:ec00:c25:c25e:dd:dd4e:c773
1872c19:dd:ec00:c25:c25e:dd:dd4e:c774/1272c19:dd:ec00:c25:c25e:dd:dd4e:c775
1882c19:dd:ec00:c25:c25e:dd:dd4e:c776/1272c19:dd:ec00:c25:c25e:dd:dd4e:c777
1892c19:dd:ec00:c25:c25e:dd:dd4e:c778/1272c19:dd:ec00:c25:c25e:dd:dd4e:c779
1902c19:dd:ec00:c25:c25e:dd:dd4e:c77a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c77b
1912c19:dd:ec00:c25:c25e:dd:dd4e:c77c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c77d
1922c19:dd:ec00:c25:c25e:dd:dd4e:c77e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c77f
1932c19:dd:ec00:c25:c25e:dd:dd4e:c780/1272c19:dd:ec00:c25:c25e:dd:dd4e:c781
1942c19:dd:ec00:c25:c25e:dd:dd4e:c782/1272c19:dd:ec00:c25:c25e:dd:dd4e:c783
1952c19:dd:ec00:c25:c25e:dd:dd4e:c784/1272c19:dd:ec00:c25:c25e:dd:dd4e:c785
1962c19:dd:ec00:c25:c25e:dd:dd4e:c786/1272c19:dd:ec00:c25:c25e:dd:dd4e:c787
1972c19:dd:ec00:c25:c25e:dd:dd4e:c788/1272c19:dd:ec00:c25:c25e:dd:dd4e:c789
1982c19:dd:ec00:c25:c25e:dd:dd4e:c78a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c78b
1992c19:dd:ec00:c25:c25e:dd:dd4e:c78c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c78d
2002c19:dd:ec00:c25:c25e:dd:dd4e:c78e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c78f
2012c19:dd:ec00:c25:c25e:dd:dd4e:c790/1272c19:dd:ec00:c25:c25e:dd:dd4e:c791
2022c19:dd:ec00:c25:c25e:dd:dd4e:c792/1272c19:dd:ec00:c25:c25e:dd:dd4e:c793
2032c19:dd:ec00:c25:c25e:dd:dd4e:c794/1272c19:dd:ec00:c25:c25e:dd:dd4e:c795
2042c19:dd:ec00:c25:c25e:dd:dd4e:c796/1272c19:dd:ec00:c25:c25e:dd:dd4e:c797
2052c19:dd:ec00:c25:c25e:dd:dd4e:c798/1272c19:dd:ec00:c25:c25e:dd:dd4e:c799
2062c19:dd:ec00:c25:c25e:dd:dd4e:c79a/1272c19:dd:ec00:c25:c25e:dd:dd4e:c79b
2072c19:dd:ec00:c25:c25e:dd:dd4e:c79c/1272c19:dd:ec00:c25:c25e:dd:dd4e:c79d
2082c19:dd:ec00:c25:c25e:dd:dd4e:c79e/1272c19:dd:ec00:c25:c25e:dd:dd4e:c79f
2092c19:dd:ec00:c25:c25e:dd:dd4e:c7a0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7a1
2102c19:dd:ec00:c25:c25e:dd:dd4e:c7a2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7a3
2112c19:dd:ec00:c25:c25e:dd:dd4e:c7a4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7a5
2122c19:dd:ec00:c25:c25e:dd:dd4e:c7a6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7a7
2132c19:dd:ec00:c25:c25e:dd:dd4e:c7a8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7a9
2142c19:dd:ec00:c25:c25e:dd:dd4e:c7aa/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7ab
2152c19:dd:ec00:c25:c25e:dd:dd4e:c7ac/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7ad
2162c19:dd:ec00:c25:c25e:dd:dd4e:c7ae/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7af
2172c19:dd:ec00:c25:c25e:dd:dd4e:c7b0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7b1
2182c19:dd:ec00:c25:c25e:dd:dd4e:c7b2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7b3
2192c19:dd:ec00:c25:c25e:dd:dd4e:c7b4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7b5
2202c19:dd:ec00:c25:c25e:dd:dd4e:c7b6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7b7
2212c19:dd:ec00:c25:c25e:dd:dd4e:c7b8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7b9
2222c19:dd:ec00:c25:c25e:dd:dd4e:c7ba/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7bb
2232c19:dd:ec00:c25:c25e:dd:dd4e:c7bc/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7bd
2242c19:dd:ec00:c25:c25e:dd:dd4e:c7be/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7bf
2252c19:dd:ec00:c25:c25e:dd:dd4e:c7c0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7c1
2262c19:dd:ec00:c25:c25e:dd:dd4e:c7c2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7c3
2272c19:dd:ec00:c25:c25e:dd:dd4e:c7c4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7c5
2282c19:dd:ec00:c25:c25e:dd:dd4e:c7c6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7c7
2292c19:dd:ec00:c25:c25e:dd:dd4e:c7c8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7c9
2302c19:dd:ec00:c25:c25e:dd:dd4e:c7ca/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7cb
2312c19:dd:ec00:c25:c25e:dd:dd4e:c7cc/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7cd
2322c19:dd:ec00:c25:c25e:dd:dd4e:c7ce/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7cf
2332c19:dd:ec00:c25:c25e:dd:dd4e:c7d0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7d1
2342c19:dd:ec00:c25:c25e:dd:dd4e:c7d2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7d3
2352c19:dd:ec00:c25:c25e:dd:dd4e:c7d4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7d5
2362c19:dd:ec00:c25:c25e:dd:dd4e:c7d6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7d7
2372c19:dd:ec00:c25:c25e:dd:dd4e:c7d8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7d9
2382c19:dd:ec00:c25:c25e:dd:dd4e:c7da/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7db
2392c19:dd:ec00:c25:c25e:dd:dd4e:c7dc/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7dd
2402c19:dd:ec00:c25:c25e:dd:dd4e:c7de/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7df
2412c19:dd:ec00:c25:c25e:dd:dd4e:c7e0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7e1
2422c19:dd:ec00:c25:c25e:dd:dd4e:c7e2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7e3
2432c19:dd:ec00:c25:c25e:dd:dd4e:c7e4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7e5
2442c19:dd:ec00:c25:c25e:dd:dd4e:c7e6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7e7
2452c19:dd:ec00:c25:c25e:dd:dd4e:c7e8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7e9
2462c19:dd:ec00:c25:c25e:dd:dd4e:c7ea/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7eb
2472c19:dd:ec00:c25:c25e:dd:dd4e:c7ec/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7ed
2482c19:dd:ec00:c25:c25e:dd:dd4e:c7ee/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7ef
2492c19:dd:ec00:c25:c25e:dd:dd4e:c7f0/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7f1
2502c19:dd:ec00:c25:c25e:dd:dd4e:c7f2/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7f3
2512c19:dd:ec00:c25:c25e:dd:dd4e:c7f4/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7f5
2522c19:dd:ec00:c25:c25e:dd:dd4e:c7f6/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7f7
2532c19:dd:ec00:c25:c25e:dd:dd4e:c7f8/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7f9
2542c19:dd:ec00:c25:c25e:dd:dd4e:c7fa/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7fb
2552c19:dd:ec00:c25:c25e:dd:dd4e:c7fc/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7fd
2562c19:dd:ec00:c25:c25e:dd:dd4e:c7fe/1272c19:dd:ec00:c25:c25e:dd:dd4e:c7ff

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.