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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:d9:dd:c25:c25:c00a:d600/119
First address
2c19:dd:d9:dd:c25:c25:c00a:d600
Last address
2c19:dd:d9:dd:c25:c25:c00a:d7ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:c00a:d600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
6.d.a.0.0.c.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
7.d.a.0.0.c.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
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/128
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:c00a:d600/119 makes 512 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:c00a:d600/1282c19:dd:d9:dd:c25:c25:c00a:d600
22c19:dd:d9:dd:c25:c25:c00a:d601/1282c19:dd:d9:dd:c25:c25:c00a:d601
32c19:dd:d9:dd:c25:c25:c00a:d602/1282c19:dd:d9:dd:c25:c25:c00a:d602
42c19:dd:d9:dd:c25:c25:c00a:d603/1282c19:dd:d9:dd:c25:c25:c00a:d603
52c19:dd:d9:dd:c25:c25:c00a:d604/1282c19:dd:d9:dd:c25:c25:c00a:d604
62c19:dd:d9:dd:c25:c25:c00a:d605/1282c19:dd:d9:dd:c25:c25:c00a:d605
72c19:dd:d9:dd:c25:c25:c00a:d606/1282c19:dd:d9:dd:c25:c25:c00a:d606
82c19:dd:d9:dd:c25:c25:c00a:d607/1282c19:dd:d9:dd:c25:c25:c00a:d607
92c19:dd:d9:dd:c25:c25:c00a:d608/1282c19:dd:d9:dd:c25:c25:c00a:d608
102c19:dd:d9:dd:c25:c25:c00a:d609/1282c19:dd:d9:dd:c25:c25:c00a:d609
112c19:dd:d9:dd:c25:c25:c00a:d60a/1282c19:dd:d9:dd:c25:c25:c00a:d60a
122c19:dd:d9:dd:c25:c25:c00a:d60b/1282c19:dd:d9:dd:c25:c25:c00a:d60b
132c19:dd:d9:dd:c25:c25:c00a:d60c/1282c19:dd:d9:dd:c25:c25:c00a:d60c
142c19:dd:d9:dd:c25:c25:c00a:d60d/1282c19:dd:d9:dd:c25:c25:c00a:d60d
152c19:dd:d9:dd:c25:c25:c00a:d60e/1282c19:dd:d9:dd:c25:c25:c00a:d60e
162c19:dd:d9:dd:c25:c25:c00a:d60f/1282c19:dd:d9:dd:c25:c25:c00a:d60f
172c19:dd:d9:dd:c25:c25:c00a:d610/1282c19:dd:d9:dd:c25:c25:c00a:d610
182c19:dd:d9:dd:c25:c25:c00a:d611/1282c19:dd:d9:dd:c25:c25:c00a:d611
192c19:dd:d9:dd:c25:c25:c00a:d612/1282c19:dd:d9:dd:c25:c25:c00a:d612
202c19:dd:d9:dd:c25:c25:c00a:d613/1282c19:dd:d9:dd:c25:c25:c00a:d613
212c19:dd:d9:dd:c25:c25:c00a:d614/1282c19:dd:d9:dd:c25:c25:c00a:d614
222c19:dd:d9:dd:c25:c25:c00a:d615/1282c19:dd:d9:dd:c25:c25:c00a:d615
232c19:dd:d9:dd:c25:c25:c00a:d616/1282c19:dd:d9:dd:c25:c25:c00a:d616
242c19:dd:d9:dd:c25:c25:c00a:d617/1282c19:dd:d9:dd:c25:c25:c00a:d617
252c19:dd:d9:dd:c25:c25:c00a:d618/1282c19:dd:d9:dd:c25:c25:c00a:d618
262c19:dd:d9:dd:c25:c25:c00a:d619/1282c19:dd:d9:dd:c25:c25:c00a:d619
272c19:dd:d9:dd:c25:c25:c00a:d61a/1282c19:dd:d9:dd:c25:c25:c00a:d61a
282c19:dd:d9:dd:c25:c25:c00a:d61b/1282c19:dd:d9:dd:c25:c25:c00a:d61b
292c19:dd:d9:dd:c25:c25:c00a:d61c/1282c19:dd:d9:dd:c25:c25:c00a:d61c
302c19:dd:d9:dd:c25:c25:c00a:d61d/1282c19:dd:d9:dd:c25:c25:c00a:d61d
312c19:dd:d9:dd:c25:c25:c00a:d61e/1282c19:dd:d9:dd:c25:c25:c00a:d61e
322c19:dd:d9:dd:c25:c25:c00a:d61f/1282c19:dd:d9:dd:c25:c25:c00a:d61f
332c19:dd:d9:dd:c25:c25:c00a:d620/1282c19:dd:d9:dd:c25:c25:c00a:d620
342c19:dd:d9:dd:c25:c25:c00a:d621/1282c19:dd:d9:dd:c25:c25:c00a:d621
352c19:dd:d9:dd:c25:c25:c00a:d622/1282c19:dd:d9:dd:c25:c25:c00a:d622
362c19:dd:d9:dd:c25:c25:c00a:d623/1282c19:dd:d9:dd:c25:c25:c00a:d623
372c19:dd:d9:dd:c25:c25:c00a:d624/1282c19:dd:d9:dd:c25:c25:c00a:d624
382c19:dd:d9:dd:c25:c25:c00a:d625/1282c19:dd:d9:dd:c25:c25:c00a:d625
392c19:dd:d9:dd:c25:c25:c00a:d626/1282c19:dd:d9:dd:c25:c25:c00a:d626
402c19:dd:d9:dd:c25:c25:c00a:d627/1282c19:dd:d9:dd:c25:c25:c00a:d627
412c19:dd:d9:dd:c25:c25:c00a:d628/1282c19:dd:d9:dd:c25:c25:c00a:d628
422c19:dd:d9:dd:c25:c25:c00a:d629/1282c19:dd:d9:dd:c25:c25:c00a:d629
432c19:dd:d9:dd:c25:c25:c00a:d62a/1282c19:dd:d9:dd:c25:c25:c00a:d62a
442c19:dd:d9:dd:c25:c25:c00a:d62b/1282c19:dd:d9:dd:c25:c25:c00a:d62b
452c19:dd:d9:dd:c25:c25:c00a:d62c/1282c19:dd:d9:dd:c25:c25:c00a:d62c
462c19:dd:d9:dd:c25:c25:c00a:d62d/1282c19:dd:d9:dd:c25:c25:c00a:d62d
472c19:dd:d9:dd:c25:c25:c00a:d62e/1282c19:dd:d9:dd:c25:c25:c00a:d62e
482c19:dd:d9:dd:c25:c25:c00a:d62f/1282c19:dd:d9:dd:c25:c25:c00a:d62f
492c19:dd:d9:dd:c25:c25:c00a:d630/1282c19:dd:d9:dd:c25:c25:c00a:d630
502c19:dd:d9:dd:c25:c25:c00a:d631/1282c19:dd:d9:dd:c25:c25:c00a:d631
512c19:dd:d9:dd:c25:c25:c00a:d632/1282c19:dd:d9:dd:c25:c25:c00a:d632
522c19:dd:d9:dd:c25:c25:c00a:d633/1282c19:dd:d9:dd:c25:c25:c00a:d633
532c19:dd:d9:dd:c25:c25:c00a:d634/1282c19:dd:d9:dd:c25:c25:c00a:d634
542c19:dd:d9:dd:c25:c25:c00a:d635/1282c19:dd:d9:dd:c25:c25:c00a:d635
552c19:dd:d9:dd:c25:c25:c00a:d636/1282c19:dd:d9:dd:c25:c25:c00a:d636
562c19:dd:d9:dd:c25:c25:c00a:d637/1282c19:dd:d9:dd:c25:c25:c00a:d637
572c19:dd:d9:dd:c25:c25:c00a:d638/1282c19:dd:d9:dd:c25:c25:c00a:d638
582c19:dd:d9:dd:c25:c25:c00a:d639/1282c19:dd:d9:dd:c25:c25:c00a:d639
592c19:dd:d9:dd:c25:c25:c00a:d63a/1282c19:dd:d9:dd:c25:c25:c00a:d63a
602c19:dd:d9:dd:c25:c25:c00a:d63b/1282c19:dd:d9:dd:c25:c25:c00a:d63b
612c19:dd:d9:dd:c25:c25:c00a:d63c/1282c19:dd:d9:dd:c25:c25:c00a:d63c
622c19:dd:d9:dd:c25:c25:c00a:d63d/1282c19:dd:d9:dd:c25:c25:c00a:d63d
632c19:dd:d9:dd:c25:c25:c00a:d63e/1282c19:dd:d9:dd:c25:c25:c00a:d63e
642c19:dd:d9:dd:c25:c25:c00a:d63f/1282c19:dd:d9:dd:c25:c25:c00a:d63f
652c19:dd:d9:dd:c25:c25:c00a:d640/1282c19:dd:d9:dd:c25:c25:c00a:d640
662c19:dd:d9:dd:c25:c25:c00a:d641/1282c19:dd:d9:dd:c25:c25:c00a:d641
672c19:dd:d9:dd:c25:c25:c00a:d642/1282c19:dd:d9:dd:c25:c25:c00a:d642
682c19:dd:d9:dd:c25:c25:c00a:d643/1282c19:dd:d9:dd:c25:c25:c00a:d643
692c19:dd:d9:dd:c25:c25:c00a:d644/1282c19:dd:d9:dd:c25:c25:c00a:d644
702c19:dd:d9:dd:c25:c25:c00a:d645/1282c19:dd:d9:dd:c25:c25:c00a:d645
712c19:dd:d9:dd:c25:c25:c00a:d646/1282c19:dd:d9:dd:c25:c25:c00a:d646
722c19:dd:d9:dd:c25:c25:c00a:d647/1282c19:dd:d9:dd:c25:c25:c00a:d647
732c19:dd:d9:dd:c25:c25:c00a:d648/1282c19:dd:d9:dd:c25:c25:c00a:d648
742c19:dd:d9:dd:c25:c25:c00a:d649/1282c19:dd:d9:dd:c25:c25:c00a:d649
752c19:dd:d9:dd:c25:c25:c00a:d64a/1282c19:dd:d9:dd:c25:c25:c00a:d64a
762c19:dd:d9:dd:c25:c25:c00a:d64b/1282c19:dd:d9:dd:c25:c25:c00a:d64b
772c19:dd:d9:dd:c25:c25:c00a:d64c/1282c19:dd:d9:dd:c25:c25:c00a:d64c
782c19:dd:d9:dd:c25:c25:c00a:d64d/1282c19:dd:d9:dd:c25:c25:c00a:d64d
792c19:dd:d9:dd:c25:c25:c00a:d64e/1282c19:dd:d9:dd:c25:c25:c00a:d64e
802c19:dd:d9:dd:c25:c25:c00a:d64f/1282c19:dd:d9:dd:c25:c25:c00a:d64f
812c19:dd:d9:dd:c25:c25:c00a:d650/1282c19:dd:d9:dd:c25:c25:c00a:d650
822c19:dd:d9:dd:c25:c25:c00a:d651/1282c19:dd:d9:dd:c25:c25:c00a:d651
832c19:dd:d9:dd:c25:c25:c00a:d652/1282c19:dd:d9:dd:c25:c25:c00a:d652
842c19:dd:d9:dd:c25:c25:c00a:d653/1282c19:dd:d9:dd:c25:c25:c00a:d653
852c19:dd:d9:dd:c25:c25:c00a:d654/1282c19:dd:d9:dd:c25:c25:c00a:d654
862c19:dd:d9:dd:c25:c25:c00a:d655/1282c19:dd:d9:dd:c25:c25:c00a:d655
872c19:dd:d9:dd:c25:c25:c00a:d656/1282c19:dd:d9:dd:c25:c25:c00a:d656
882c19:dd:d9:dd:c25:c25:c00a:d657/1282c19:dd:d9:dd:c25:c25:c00a:d657
892c19:dd:d9:dd:c25:c25:c00a:d658/1282c19:dd:d9:dd:c25:c25:c00a:d658
902c19:dd:d9:dd:c25:c25:c00a:d659/1282c19:dd:d9:dd:c25:c25:c00a:d659
912c19:dd:d9:dd:c25:c25:c00a:d65a/1282c19:dd:d9:dd:c25:c25:c00a:d65a
922c19:dd:d9:dd:c25:c25:c00a:d65b/1282c19:dd:d9:dd:c25:c25:c00a:d65b
932c19:dd:d9:dd:c25:c25:c00a:d65c/1282c19:dd:d9:dd:c25:c25:c00a:d65c
942c19:dd:d9:dd:c25:c25:c00a:d65d/1282c19:dd:d9:dd:c25:c25:c00a:d65d
952c19:dd:d9:dd:c25:c25:c00a:d65e/1282c19:dd:d9:dd:c25:c25:c00a:d65e
962c19:dd:d9:dd:c25:c25:c00a:d65f/1282c19:dd:d9:dd:c25:c25:c00a:d65f
972c19:dd:d9:dd:c25:c25:c00a:d660/1282c19:dd:d9:dd:c25:c25:c00a:d660
982c19:dd:d9:dd:c25:c25:c00a:d661/1282c19:dd:d9:dd:c25:c25:c00a:d661
992c19:dd:d9:dd:c25:c25:c00a:d662/1282c19:dd:d9:dd:c25:c25:c00a:d662
1002c19:dd:d9:dd:c25:c25:c00a:d663/1282c19:dd:d9:dd:c25:c25:c00a:d663
1012c19:dd:d9:dd:c25:c25:c00a:d664/1282c19:dd:d9:dd:c25:c25:c00a:d664
1022c19:dd:d9:dd:c25:c25:c00a:d665/1282c19:dd:d9:dd:c25:c25:c00a:d665
1032c19:dd:d9:dd:c25:c25:c00a:d666/1282c19:dd:d9:dd:c25:c25:c00a:d666
1042c19:dd:d9:dd:c25:c25:c00a:d667/1282c19:dd:d9:dd:c25:c25:c00a:d667
1052c19:dd:d9:dd:c25:c25:c00a:d668/1282c19:dd:d9:dd:c25:c25:c00a:d668
1062c19:dd:d9:dd:c25:c25:c00a:d669/1282c19:dd:d9:dd:c25:c25:c00a:d669
1072c19:dd:d9:dd:c25:c25:c00a:d66a/1282c19:dd:d9:dd:c25:c25:c00a:d66a
1082c19:dd:d9:dd:c25:c25:c00a:d66b/1282c19:dd:d9:dd:c25:c25:c00a:d66b
1092c19:dd:d9:dd:c25:c25:c00a:d66c/1282c19:dd:d9:dd:c25:c25:c00a:d66c
1102c19:dd:d9:dd:c25:c25:c00a:d66d/1282c19:dd:d9:dd:c25:c25:c00a:d66d
1112c19:dd:d9:dd:c25:c25:c00a:d66e/1282c19:dd:d9:dd:c25:c25:c00a:d66e
1122c19:dd:d9:dd:c25:c25:c00a:d66f/1282c19:dd:d9:dd:c25:c25:c00a:d66f
1132c19:dd:d9:dd:c25:c25:c00a:d670/1282c19:dd:d9:dd:c25:c25:c00a:d670
1142c19:dd:d9:dd:c25:c25:c00a:d671/1282c19:dd:d9:dd:c25:c25:c00a:d671
1152c19:dd:d9:dd:c25:c25:c00a:d672/1282c19:dd:d9:dd:c25:c25:c00a:d672
1162c19:dd:d9:dd:c25:c25:c00a:d673/1282c19:dd:d9:dd:c25:c25:c00a:d673
1172c19:dd:d9:dd:c25:c25:c00a:d674/1282c19:dd:d9:dd:c25:c25:c00a:d674
1182c19:dd:d9:dd:c25:c25:c00a:d675/1282c19:dd:d9:dd:c25:c25:c00a:d675
1192c19:dd:d9:dd:c25:c25:c00a:d676/1282c19:dd:d9:dd:c25:c25:c00a:d676
1202c19:dd:d9:dd:c25:c25:c00a:d677/1282c19:dd:d9:dd:c25:c25:c00a:d677
1212c19:dd:d9:dd:c25:c25:c00a:d678/1282c19:dd:d9:dd:c25:c25:c00a:d678
1222c19:dd:d9:dd:c25:c25:c00a:d679/1282c19:dd:d9:dd:c25:c25:c00a:d679
1232c19:dd:d9:dd:c25:c25:c00a:d67a/1282c19:dd:d9:dd:c25:c25:c00a:d67a
1242c19:dd:d9:dd:c25:c25:c00a:d67b/1282c19:dd:d9:dd:c25:c25:c00a:d67b
1252c19:dd:d9:dd:c25:c25:c00a:d67c/1282c19:dd:d9:dd:c25:c25:c00a:d67c
1262c19:dd:d9:dd:c25:c25:c00a:d67d/1282c19:dd:d9:dd:c25:c25:c00a:d67d
1272c19:dd:d9:dd:c25:c25:c00a:d67e/1282c19:dd:d9:dd:c25:c25:c00a:d67e
1282c19:dd:d9:dd:c25:c25:c00a:d67f/1282c19:dd:d9:dd:c25:c25:c00a:d67f
1292c19:dd:d9:dd:c25:c25:c00a:d680/1282c19:dd:d9:dd:c25:c25:c00a:d680
1302c19:dd:d9:dd:c25:c25:c00a:d681/1282c19:dd:d9:dd:c25:c25:c00a:d681
1312c19:dd:d9:dd:c25:c25:c00a:d682/1282c19:dd:d9:dd:c25:c25:c00a:d682
1322c19:dd:d9:dd:c25:c25:c00a:d683/1282c19:dd:d9:dd:c25:c25:c00a:d683
1332c19:dd:d9:dd:c25:c25:c00a:d684/1282c19:dd:d9:dd:c25:c25:c00a:d684
1342c19:dd:d9:dd:c25:c25:c00a:d685/1282c19:dd:d9:dd:c25:c25:c00a:d685
1352c19:dd:d9:dd:c25:c25:c00a:d686/1282c19:dd:d9:dd:c25:c25:c00a:d686
1362c19:dd:d9:dd:c25:c25:c00a:d687/1282c19:dd:d9:dd:c25:c25:c00a:d687
1372c19:dd:d9:dd:c25:c25:c00a:d688/1282c19:dd:d9:dd:c25:c25:c00a:d688
1382c19:dd:d9:dd:c25:c25:c00a:d689/1282c19:dd:d9:dd:c25:c25:c00a:d689
1392c19:dd:d9:dd:c25:c25:c00a:d68a/1282c19:dd:d9:dd:c25:c25:c00a:d68a
1402c19:dd:d9:dd:c25:c25:c00a:d68b/1282c19:dd:d9:dd:c25:c25:c00a:d68b
1412c19:dd:d9:dd:c25:c25:c00a:d68c/1282c19:dd:d9:dd:c25:c25:c00a:d68c
1422c19:dd:d9:dd:c25:c25:c00a:d68d/1282c19:dd:d9:dd:c25:c25:c00a:d68d
1432c19:dd:d9:dd:c25:c25:c00a:d68e/1282c19:dd:d9:dd:c25:c25:c00a:d68e
1442c19:dd:d9:dd:c25:c25:c00a:d68f/1282c19:dd:d9:dd:c25:c25:c00a:d68f
1452c19:dd:d9:dd:c25:c25:c00a:d690/1282c19:dd:d9:dd:c25:c25:c00a:d690
1462c19:dd:d9:dd:c25:c25:c00a:d691/1282c19:dd:d9:dd:c25:c25:c00a:d691
1472c19:dd:d9:dd:c25:c25:c00a:d692/1282c19:dd:d9:dd:c25:c25:c00a:d692
1482c19:dd:d9:dd:c25:c25:c00a:d693/1282c19:dd:d9:dd:c25:c25:c00a:d693
1492c19:dd:d9:dd:c25:c25:c00a:d694/1282c19:dd:d9:dd:c25:c25:c00a:d694
1502c19:dd:d9:dd:c25:c25:c00a:d695/1282c19:dd:d9:dd:c25:c25:c00a:d695
1512c19:dd:d9:dd:c25:c25:c00a:d696/1282c19:dd:d9:dd:c25:c25:c00a:d696
1522c19:dd:d9:dd:c25:c25:c00a:d697/1282c19:dd:d9:dd:c25:c25:c00a:d697
1532c19:dd:d9:dd:c25:c25:c00a:d698/1282c19:dd:d9:dd:c25:c25:c00a:d698
1542c19:dd:d9:dd:c25:c25:c00a:d699/1282c19:dd:d9:dd:c25:c25:c00a:d699
1552c19:dd:d9:dd:c25:c25:c00a:d69a/1282c19:dd:d9:dd:c25:c25:c00a:d69a
1562c19:dd:d9:dd:c25:c25:c00a:d69b/1282c19:dd:d9:dd:c25:c25:c00a:d69b
1572c19:dd:d9:dd:c25:c25:c00a:d69c/1282c19:dd:d9:dd:c25:c25:c00a:d69c
1582c19:dd:d9:dd:c25:c25:c00a:d69d/1282c19:dd:d9:dd:c25:c25:c00a:d69d
1592c19:dd:d9:dd:c25:c25:c00a:d69e/1282c19:dd:d9:dd:c25:c25:c00a:d69e
1602c19:dd:d9:dd:c25:c25:c00a:d69f/1282c19:dd:d9:dd:c25:c25:c00a:d69f
1612c19:dd:d9:dd:c25:c25:c00a:d6a0/1282c19:dd:d9:dd:c25:c25:c00a:d6a0
1622c19:dd:d9:dd:c25:c25:c00a:d6a1/1282c19:dd:d9:dd:c25:c25:c00a:d6a1
1632c19:dd:d9:dd:c25:c25:c00a:d6a2/1282c19:dd:d9:dd:c25:c25:c00a:d6a2
1642c19:dd:d9:dd:c25:c25:c00a:d6a3/1282c19:dd:d9:dd:c25:c25:c00a:d6a3
1652c19:dd:d9:dd:c25:c25:c00a:d6a4/1282c19:dd:d9:dd:c25:c25:c00a:d6a4
1662c19:dd:d9:dd:c25:c25:c00a:d6a5/1282c19:dd:d9:dd:c25:c25:c00a:d6a5
1672c19:dd:d9:dd:c25:c25:c00a:d6a6/1282c19:dd:d9:dd:c25:c25:c00a:d6a6
1682c19:dd:d9:dd:c25:c25:c00a:d6a7/1282c19:dd:d9:dd:c25:c25:c00a:d6a7
1692c19:dd:d9:dd:c25:c25:c00a:d6a8/1282c19:dd:d9:dd:c25:c25:c00a:d6a8
1702c19:dd:d9:dd:c25:c25:c00a:d6a9/1282c19:dd:d9:dd:c25:c25:c00a:d6a9
1712c19:dd:d9:dd:c25:c25:c00a:d6aa/1282c19:dd:d9:dd:c25:c25:c00a:d6aa
1722c19:dd:d9:dd:c25:c25:c00a:d6ab/1282c19:dd:d9:dd:c25:c25:c00a:d6ab
1732c19:dd:d9:dd:c25:c25:c00a:d6ac/1282c19:dd:d9:dd:c25:c25:c00a:d6ac
1742c19:dd:d9:dd:c25:c25:c00a:d6ad/1282c19:dd:d9:dd:c25:c25:c00a:d6ad
1752c19:dd:d9:dd:c25:c25:c00a:d6ae/1282c19:dd:d9:dd:c25:c25:c00a:d6ae
1762c19:dd:d9:dd:c25:c25:c00a:d6af/1282c19:dd:d9:dd:c25:c25:c00a:d6af
1772c19:dd:d9:dd:c25:c25:c00a:d6b0/1282c19:dd:d9:dd:c25:c25:c00a:d6b0
1782c19:dd:d9:dd:c25:c25:c00a:d6b1/1282c19:dd:d9:dd:c25:c25:c00a:d6b1
1792c19:dd:d9:dd:c25:c25:c00a:d6b2/1282c19:dd:d9:dd:c25:c25:c00a:d6b2
1802c19:dd:d9:dd:c25:c25:c00a:d6b3/1282c19:dd:d9:dd:c25:c25:c00a:d6b3
1812c19:dd:d9:dd:c25:c25:c00a:d6b4/1282c19:dd:d9:dd:c25:c25:c00a:d6b4
1822c19:dd:d9:dd:c25:c25:c00a:d6b5/1282c19:dd:d9:dd:c25:c25:c00a:d6b5
1832c19:dd:d9:dd:c25:c25:c00a:d6b6/1282c19:dd:d9:dd:c25:c25:c00a:d6b6
1842c19:dd:d9:dd:c25:c25:c00a:d6b7/1282c19:dd:d9:dd:c25:c25:c00a:d6b7
1852c19:dd:d9:dd:c25:c25:c00a:d6b8/1282c19:dd:d9:dd:c25:c25:c00a:d6b8
1862c19:dd:d9:dd:c25:c25:c00a:d6b9/1282c19:dd:d9:dd:c25:c25:c00a:d6b9
1872c19:dd:d9:dd:c25:c25:c00a:d6ba/1282c19:dd:d9:dd:c25:c25:c00a:d6ba
1882c19:dd:d9:dd:c25:c25:c00a:d6bb/1282c19:dd:d9:dd:c25:c25:c00a:d6bb
1892c19:dd:d9:dd:c25:c25:c00a:d6bc/1282c19:dd:d9:dd:c25:c25:c00a:d6bc
1902c19:dd:d9:dd:c25:c25:c00a:d6bd/1282c19:dd:d9:dd:c25:c25:c00a:d6bd
1912c19:dd:d9:dd:c25:c25:c00a:d6be/1282c19:dd:d9:dd:c25:c25:c00a:d6be
1922c19:dd:d9:dd:c25:c25:c00a:d6bf/1282c19:dd:d9:dd:c25:c25:c00a:d6bf
1932c19:dd:d9:dd:c25:c25:c00a:d6c0/1282c19:dd:d9:dd:c25:c25:c00a:d6c0
1942c19:dd:d9:dd:c25:c25:c00a:d6c1/1282c19:dd:d9:dd:c25:c25:c00a:d6c1
1952c19:dd:d9:dd:c25:c25:c00a:d6c2/1282c19:dd:d9:dd:c25:c25:c00a:d6c2
1962c19:dd:d9:dd:c25:c25:c00a:d6c3/1282c19:dd:d9:dd:c25:c25:c00a:d6c3
1972c19:dd:d9:dd:c25:c25:c00a:d6c4/1282c19:dd:d9:dd:c25:c25:c00a:d6c4
1982c19:dd:d9:dd:c25:c25:c00a:d6c5/1282c19:dd:d9:dd:c25:c25:c00a:d6c5
1992c19:dd:d9:dd:c25:c25:c00a:d6c6/1282c19:dd:d9:dd:c25:c25:c00a:d6c6
2002c19:dd:d9:dd:c25:c25:c00a:d6c7/1282c19:dd:d9:dd:c25:c25:c00a:d6c7
2012c19:dd:d9:dd:c25:c25:c00a:d6c8/1282c19:dd:d9:dd:c25:c25:c00a:d6c8
2022c19:dd:d9:dd:c25:c25:c00a:d6c9/1282c19:dd:d9:dd:c25:c25:c00a:d6c9
2032c19:dd:d9:dd:c25:c25:c00a:d6ca/1282c19:dd:d9:dd:c25:c25:c00a:d6ca
2042c19:dd:d9:dd:c25:c25:c00a:d6cb/1282c19:dd:d9:dd:c25:c25:c00a:d6cb
2052c19:dd:d9:dd:c25:c25:c00a:d6cc/1282c19:dd:d9:dd:c25:c25:c00a:d6cc
2062c19:dd:d9:dd:c25:c25:c00a:d6cd/1282c19:dd:d9:dd:c25:c25:c00a:d6cd
2072c19:dd:d9:dd:c25:c25:c00a:d6ce/1282c19:dd:d9:dd:c25:c25:c00a:d6ce
2082c19:dd:d9:dd:c25:c25:c00a:d6cf/1282c19:dd:d9:dd:c25:c25:c00a:d6cf
2092c19:dd:d9:dd:c25:c25:c00a:d6d0/1282c19:dd:d9:dd:c25:c25:c00a:d6d0
2102c19:dd:d9:dd:c25:c25:c00a:d6d1/1282c19:dd:d9:dd:c25:c25:c00a:d6d1
2112c19:dd:d9:dd:c25:c25:c00a:d6d2/1282c19:dd:d9:dd:c25:c25:c00a:d6d2
2122c19:dd:d9:dd:c25:c25:c00a:d6d3/1282c19:dd:d9:dd:c25:c25:c00a:d6d3
2132c19:dd:d9:dd:c25:c25:c00a:d6d4/1282c19:dd:d9:dd:c25:c25:c00a:d6d4
2142c19:dd:d9:dd:c25:c25:c00a:d6d5/1282c19:dd:d9:dd:c25:c25:c00a:d6d5
2152c19:dd:d9:dd:c25:c25:c00a:d6d6/1282c19:dd:d9:dd:c25:c25:c00a:d6d6
2162c19:dd:d9:dd:c25:c25:c00a:d6d7/1282c19:dd:d9:dd:c25:c25:c00a:d6d7
2172c19:dd:d9:dd:c25:c25:c00a:d6d8/1282c19:dd:d9:dd:c25:c25:c00a:d6d8
2182c19:dd:d9:dd:c25:c25:c00a:d6d9/1282c19:dd:d9:dd:c25:c25:c00a:d6d9
2192c19:dd:d9:dd:c25:c25:c00a:d6da/1282c19:dd:d9:dd:c25:c25:c00a:d6da
2202c19:dd:d9:dd:c25:c25:c00a:d6db/1282c19:dd:d9:dd:c25:c25:c00a:d6db
2212c19:dd:d9:dd:c25:c25:c00a:d6dc/1282c19:dd:d9:dd:c25:c25:c00a:d6dc
2222c19:dd:d9:dd:c25:c25:c00a:d6dd/1282c19:dd:d9:dd:c25:c25:c00a:d6dd
2232c19:dd:d9:dd:c25:c25:c00a:d6de/1282c19:dd:d9:dd:c25:c25:c00a:d6de
2242c19:dd:d9:dd:c25:c25:c00a:d6df/1282c19:dd:d9:dd:c25:c25:c00a:d6df
2252c19:dd:d9:dd:c25:c25:c00a:d6e0/1282c19:dd:d9:dd:c25:c25:c00a:d6e0
2262c19:dd:d9:dd:c25:c25:c00a:d6e1/1282c19:dd:d9:dd:c25:c25:c00a:d6e1
2272c19:dd:d9:dd:c25:c25:c00a:d6e2/1282c19:dd:d9:dd:c25:c25:c00a:d6e2
2282c19:dd:d9:dd:c25:c25:c00a:d6e3/1282c19:dd:d9:dd:c25:c25:c00a:d6e3
2292c19:dd:d9:dd:c25:c25:c00a:d6e4/1282c19:dd:d9:dd:c25:c25:c00a:d6e4
2302c19:dd:d9:dd:c25:c25:c00a:d6e5/1282c19:dd:d9:dd:c25:c25:c00a:d6e5
2312c19:dd:d9:dd:c25:c25:c00a:d6e6/1282c19:dd:d9:dd:c25:c25:c00a:d6e6
2322c19:dd:d9:dd:c25:c25:c00a:d6e7/1282c19:dd:d9:dd:c25:c25:c00a:d6e7
2332c19:dd:d9:dd:c25:c25:c00a:d6e8/1282c19:dd:d9:dd:c25:c25:c00a:d6e8
2342c19:dd:d9:dd:c25:c25:c00a:d6e9/1282c19:dd:d9:dd:c25:c25:c00a:d6e9
2352c19:dd:d9:dd:c25:c25:c00a:d6ea/1282c19:dd:d9:dd:c25:c25:c00a:d6ea
2362c19:dd:d9:dd:c25:c25:c00a:d6eb/1282c19:dd:d9:dd:c25:c25:c00a:d6eb
2372c19:dd:d9:dd:c25:c25:c00a:d6ec/1282c19:dd:d9:dd:c25:c25:c00a:d6ec
2382c19:dd:d9:dd:c25:c25:c00a:d6ed/1282c19:dd:d9:dd:c25:c25:c00a:d6ed
2392c19:dd:d9:dd:c25:c25:c00a:d6ee/1282c19:dd:d9:dd:c25:c25:c00a:d6ee
2402c19:dd:d9:dd:c25:c25:c00a:d6ef/1282c19:dd:d9:dd:c25:c25:c00a:d6ef
2412c19:dd:d9:dd:c25:c25:c00a:d6f0/1282c19:dd:d9:dd:c25:c25:c00a:d6f0
2422c19:dd:d9:dd:c25:c25:c00a:d6f1/1282c19:dd:d9:dd:c25:c25:c00a:d6f1
2432c19:dd:d9:dd:c25:c25:c00a:d6f2/1282c19:dd:d9:dd:c25:c25:c00a:d6f2
2442c19:dd:d9:dd:c25:c25:c00a:d6f3/1282c19:dd:d9:dd:c25:c25:c00a:d6f3
2452c19:dd:d9:dd:c25:c25:c00a:d6f4/1282c19:dd:d9:dd:c25:c25:c00a:d6f4
2462c19:dd:d9:dd:c25:c25:c00a:d6f5/1282c19:dd:d9:dd:c25:c25:c00a:d6f5
2472c19:dd:d9:dd:c25:c25:c00a:d6f6/1282c19:dd:d9:dd:c25:c25:c00a:d6f6
2482c19:dd:d9:dd:c25:c25:c00a:d6f7/1282c19:dd:d9:dd:c25:c25:c00a:d6f7
2492c19:dd:d9:dd:c25:c25:c00a:d6f8/1282c19:dd:d9:dd:c25:c25:c00a:d6f8
2502c19:dd:d9:dd:c25:c25:c00a:d6f9/1282c19:dd:d9:dd:c25:c25:c00a:d6f9
2512c19:dd:d9:dd:c25:c25:c00a:d6fa/1282c19:dd:d9:dd:c25:c25:c00a:d6fa
2522c19:dd:d9:dd:c25:c25:c00a:d6fb/1282c19:dd:d9:dd:c25:c25:c00a:d6fb
2532c19:dd:d9:dd:c25:c25:c00a:d6fc/1282c19:dd:d9:dd:c25:c25:c00a:d6fc
2542c19:dd:d9:dd:c25:c25:c00a:d6fd/1282c19:dd:d9:dd:c25:c25:c00a:d6fd
2552c19:dd:d9:dd:c25:c25:c00a:d6fe/1282c19:dd:d9:dd:c25:c25:c00a:d6fe
2562c19:dd:d9:dd:c25:c25:c00a:d6ff/1282c19:dd:d9:dd:c25:c25:c00a:d6ff

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.