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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:a600/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:a600
Last address
2c19:dd:d9:dd:c25:c25a:d00a:a6ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:a600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.a.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:a600/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:a600/1282c19:dd:d9:dd:c25:c25a:d00a:a600
22c19:dd:d9:dd:c25:c25a:d00a:a601/1282c19:dd:d9:dd:c25:c25a:d00a:a601
32c19:dd:d9:dd:c25:c25a:d00a:a602/1282c19:dd:d9:dd:c25:c25a:d00a:a602
42c19:dd:d9:dd:c25:c25a:d00a:a603/1282c19:dd:d9:dd:c25:c25a:d00a:a603
52c19:dd:d9:dd:c25:c25a:d00a:a604/1282c19:dd:d9:dd:c25:c25a:d00a:a604
62c19:dd:d9:dd:c25:c25a:d00a:a605/1282c19:dd:d9:dd:c25:c25a:d00a:a605
72c19:dd:d9:dd:c25:c25a:d00a:a606/1282c19:dd:d9:dd:c25:c25a:d00a:a606
82c19:dd:d9:dd:c25:c25a:d00a:a607/1282c19:dd:d9:dd:c25:c25a:d00a:a607
92c19:dd:d9:dd:c25:c25a:d00a:a608/1282c19:dd:d9:dd:c25:c25a:d00a:a608
102c19:dd:d9:dd:c25:c25a:d00a:a609/1282c19:dd:d9:dd:c25:c25a:d00a:a609
112c19:dd:d9:dd:c25:c25a:d00a:a60a/1282c19:dd:d9:dd:c25:c25a:d00a:a60a
122c19:dd:d9:dd:c25:c25a:d00a:a60b/1282c19:dd:d9:dd:c25:c25a:d00a:a60b
132c19:dd:d9:dd:c25:c25a:d00a:a60c/1282c19:dd:d9:dd:c25:c25a:d00a:a60c
142c19:dd:d9:dd:c25:c25a:d00a:a60d/1282c19:dd:d9:dd:c25:c25a:d00a:a60d
152c19:dd:d9:dd:c25:c25a:d00a:a60e/1282c19:dd:d9:dd:c25:c25a:d00a:a60e
162c19:dd:d9:dd:c25:c25a:d00a:a60f/1282c19:dd:d9:dd:c25:c25a:d00a:a60f
172c19:dd:d9:dd:c25:c25a:d00a:a610/1282c19:dd:d9:dd:c25:c25a:d00a:a610
182c19:dd:d9:dd:c25:c25a:d00a:a611/1282c19:dd:d9:dd:c25:c25a:d00a:a611
192c19:dd:d9:dd:c25:c25a:d00a:a612/1282c19:dd:d9:dd:c25:c25a:d00a:a612
202c19:dd:d9:dd:c25:c25a:d00a:a613/1282c19:dd:d9:dd:c25:c25a:d00a:a613
212c19:dd:d9:dd:c25:c25a:d00a:a614/1282c19:dd:d9:dd:c25:c25a:d00a:a614
222c19:dd:d9:dd:c25:c25a:d00a:a615/1282c19:dd:d9:dd:c25:c25a:d00a:a615
232c19:dd:d9:dd:c25:c25a:d00a:a616/1282c19:dd:d9:dd:c25:c25a:d00a:a616
242c19:dd:d9:dd:c25:c25a:d00a:a617/1282c19:dd:d9:dd:c25:c25a:d00a:a617
252c19:dd:d9:dd:c25:c25a:d00a:a618/1282c19:dd:d9:dd:c25:c25a:d00a:a618
262c19:dd:d9:dd:c25:c25a:d00a:a619/1282c19:dd:d9:dd:c25:c25a:d00a:a619
272c19:dd:d9:dd:c25:c25a:d00a:a61a/1282c19:dd:d9:dd:c25:c25a:d00a:a61a
282c19:dd:d9:dd:c25:c25a:d00a:a61b/1282c19:dd:d9:dd:c25:c25a:d00a:a61b
292c19:dd:d9:dd:c25:c25a:d00a:a61c/1282c19:dd:d9:dd:c25:c25a:d00a:a61c
302c19:dd:d9:dd:c25:c25a:d00a:a61d/1282c19:dd:d9:dd:c25:c25a:d00a:a61d
312c19:dd:d9:dd:c25:c25a:d00a:a61e/1282c19:dd:d9:dd:c25:c25a:d00a:a61e
322c19:dd:d9:dd:c25:c25a:d00a:a61f/1282c19:dd:d9:dd:c25:c25a:d00a:a61f
332c19:dd:d9:dd:c25:c25a:d00a:a620/1282c19:dd:d9:dd:c25:c25a:d00a:a620
342c19:dd:d9:dd:c25:c25a:d00a:a621/1282c19:dd:d9:dd:c25:c25a:d00a:a621
352c19:dd:d9:dd:c25:c25a:d00a:a622/1282c19:dd:d9:dd:c25:c25a:d00a:a622
362c19:dd:d9:dd:c25:c25a:d00a:a623/1282c19:dd:d9:dd:c25:c25a:d00a:a623
372c19:dd:d9:dd:c25:c25a:d00a:a624/1282c19:dd:d9:dd:c25:c25a:d00a:a624
382c19:dd:d9:dd:c25:c25a:d00a:a625/1282c19:dd:d9:dd:c25:c25a:d00a:a625
392c19:dd:d9:dd:c25:c25a:d00a:a626/1282c19:dd:d9:dd:c25:c25a:d00a:a626
402c19:dd:d9:dd:c25:c25a:d00a:a627/1282c19:dd:d9:dd:c25:c25a:d00a:a627
412c19:dd:d9:dd:c25:c25a:d00a:a628/1282c19:dd:d9:dd:c25:c25a:d00a:a628
422c19:dd:d9:dd:c25:c25a:d00a:a629/1282c19:dd:d9:dd:c25:c25a:d00a:a629
432c19:dd:d9:dd:c25:c25a:d00a:a62a/1282c19:dd:d9:dd:c25:c25a:d00a:a62a
442c19:dd:d9:dd:c25:c25a:d00a:a62b/1282c19:dd:d9:dd:c25:c25a:d00a:a62b
452c19:dd:d9:dd:c25:c25a:d00a:a62c/1282c19:dd:d9:dd:c25:c25a:d00a:a62c
462c19:dd:d9:dd:c25:c25a:d00a:a62d/1282c19:dd:d9:dd:c25:c25a:d00a:a62d
472c19:dd:d9:dd:c25:c25a:d00a:a62e/1282c19:dd:d9:dd:c25:c25a:d00a:a62e
482c19:dd:d9:dd:c25:c25a:d00a:a62f/1282c19:dd:d9:dd:c25:c25a:d00a:a62f
492c19:dd:d9:dd:c25:c25a:d00a:a630/1282c19:dd:d9:dd:c25:c25a:d00a:a630
502c19:dd:d9:dd:c25:c25a:d00a:a631/1282c19:dd:d9:dd:c25:c25a:d00a:a631
512c19:dd:d9:dd:c25:c25a:d00a:a632/1282c19:dd:d9:dd:c25:c25a:d00a:a632
522c19:dd:d9:dd:c25:c25a:d00a:a633/1282c19:dd:d9:dd:c25:c25a:d00a:a633
532c19:dd:d9:dd:c25:c25a:d00a:a634/1282c19:dd:d9:dd:c25:c25a:d00a:a634
542c19:dd:d9:dd:c25:c25a:d00a:a635/1282c19:dd:d9:dd:c25:c25a:d00a:a635
552c19:dd:d9:dd:c25:c25a:d00a:a636/1282c19:dd:d9:dd:c25:c25a:d00a:a636
562c19:dd:d9:dd:c25:c25a:d00a:a637/1282c19:dd:d9:dd:c25:c25a:d00a:a637
572c19:dd:d9:dd:c25:c25a:d00a:a638/1282c19:dd:d9:dd:c25:c25a:d00a:a638
582c19:dd:d9:dd:c25:c25a:d00a:a639/1282c19:dd:d9:dd:c25:c25a:d00a:a639
592c19:dd:d9:dd:c25:c25a:d00a:a63a/1282c19:dd:d9:dd:c25:c25a:d00a:a63a
602c19:dd:d9:dd:c25:c25a:d00a:a63b/1282c19:dd:d9:dd:c25:c25a:d00a:a63b
612c19:dd:d9:dd:c25:c25a:d00a:a63c/1282c19:dd:d9:dd:c25:c25a:d00a:a63c
622c19:dd:d9:dd:c25:c25a:d00a:a63d/1282c19:dd:d9:dd:c25:c25a:d00a:a63d
632c19:dd:d9:dd:c25:c25a:d00a:a63e/1282c19:dd:d9:dd:c25:c25a:d00a:a63e
642c19:dd:d9:dd:c25:c25a:d00a:a63f/1282c19:dd:d9:dd:c25:c25a:d00a:a63f
652c19:dd:d9:dd:c25:c25a:d00a:a640/1282c19:dd:d9:dd:c25:c25a:d00a:a640
662c19:dd:d9:dd:c25:c25a:d00a:a641/1282c19:dd:d9:dd:c25:c25a:d00a:a641
672c19:dd:d9:dd:c25:c25a:d00a:a642/1282c19:dd:d9:dd:c25:c25a:d00a:a642
682c19:dd:d9:dd:c25:c25a:d00a:a643/1282c19:dd:d9:dd:c25:c25a:d00a:a643
692c19:dd:d9:dd:c25:c25a:d00a:a644/1282c19:dd:d9:dd:c25:c25a:d00a:a644
702c19:dd:d9:dd:c25:c25a:d00a:a645/1282c19:dd:d9:dd:c25:c25a:d00a:a645
712c19:dd:d9:dd:c25:c25a:d00a:a646/1282c19:dd:d9:dd:c25:c25a:d00a:a646
722c19:dd:d9:dd:c25:c25a:d00a:a647/1282c19:dd:d9:dd:c25:c25a:d00a:a647
732c19:dd:d9:dd:c25:c25a:d00a:a648/1282c19:dd:d9:dd:c25:c25a:d00a:a648
742c19:dd:d9:dd:c25:c25a:d00a:a649/1282c19:dd:d9:dd:c25:c25a:d00a:a649
752c19:dd:d9:dd:c25:c25a:d00a:a64a/1282c19:dd:d9:dd:c25:c25a:d00a:a64a
762c19:dd:d9:dd:c25:c25a:d00a:a64b/1282c19:dd:d9:dd:c25:c25a:d00a:a64b
772c19:dd:d9:dd:c25:c25a:d00a:a64c/1282c19:dd:d9:dd:c25:c25a:d00a:a64c
782c19:dd:d9:dd:c25:c25a:d00a:a64d/1282c19:dd:d9:dd:c25:c25a:d00a:a64d
792c19:dd:d9:dd:c25:c25a:d00a:a64e/1282c19:dd:d9:dd:c25:c25a:d00a:a64e
802c19:dd:d9:dd:c25:c25a:d00a:a64f/1282c19:dd:d9:dd:c25:c25a:d00a:a64f
812c19:dd:d9:dd:c25:c25a:d00a:a650/1282c19:dd:d9:dd:c25:c25a:d00a:a650
822c19:dd:d9:dd:c25:c25a:d00a:a651/1282c19:dd:d9:dd:c25:c25a:d00a:a651
832c19:dd:d9:dd:c25:c25a:d00a:a652/1282c19:dd:d9:dd:c25:c25a:d00a:a652
842c19:dd:d9:dd:c25:c25a:d00a:a653/1282c19:dd:d9:dd:c25:c25a:d00a:a653
852c19:dd:d9:dd:c25:c25a:d00a:a654/1282c19:dd:d9:dd:c25:c25a:d00a:a654
862c19:dd:d9:dd:c25:c25a:d00a:a655/1282c19:dd:d9:dd:c25:c25a:d00a:a655
872c19:dd:d9:dd:c25:c25a:d00a:a656/1282c19:dd:d9:dd:c25:c25a:d00a:a656
882c19:dd:d9:dd:c25:c25a:d00a:a657/1282c19:dd:d9:dd:c25:c25a:d00a:a657
892c19:dd:d9:dd:c25:c25a:d00a:a658/1282c19:dd:d9:dd:c25:c25a:d00a:a658
902c19:dd:d9:dd:c25:c25a:d00a:a659/1282c19:dd:d9:dd:c25:c25a:d00a:a659
912c19:dd:d9:dd:c25:c25a:d00a:a65a/1282c19:dd:d9:dd:c25:c25a:d00a:a65a
922c19:dd:d9:dd:c25:c25a:d00a:a65b/1282c19:dd:d9:dd:c25:c25a:d00a:a65b
932c19:dd:d9:dd:c25:c25a:d00a:a65c/1282c19:dd:d9:dd:c25:c25a:d00a:a65c
942c19:dd:d9:dd:c25:c25a:d00a:a65d/1282c19:dd:d9:dd:c25:c25a:d00a:a65d
952c19:dd:d9:dd:c25:c25a:d00a:a65e/1282c19:dd:d9:dd:c25:c25a:d00a:a65e
962c19:dd:d9:dd:c25:c25a:d00a:a65f/1282c19:dd:d9:dd:c25:c25a:d00a:a65f
972c19:dd:d9:dd:c25:c25a:d00a:a660/1282c19:dd:d9:dd:c25:c25a:d00a:a660
982c19:dd:d9:dd:c25:c25a:d00a:a661/1282c19:dd:d9:dd:c25:c25a:d00a:a661
992c19:dd:d9:dd:c25:c25a:d00a:a662/1282c19:dd:d9:dd:c25:c25a:d00a:a662
1002c19:dd:d9:dd:c25:c25a:d00a:a663/1282c19:dd:d9:dd:c25:c25a:d00a:a663
1012c19:dd:d9:dd:c25:c25a:d00a:a664/1282c19:dd:d9:dd:c25:c25a:d00a:a664
1022c19:dd:d9:dd:c25:c25a:d00a:a665/1282c19:dd:d9:dd:c25:c25a:d00a:a665
1032c19:dd:d9:dd:c25:c25a:d00a:a666/1282c19:dd:d9:dd:c25:c25a:d00a:a666
1042c19:dd:d9:dd:c25:c25a:d00a:a667/1282c19:dd:d9:dd:c25:c25a:d00a:a667
1052c19:dd:d9:dd:c25:c25a:d00a:a668/1282c19:dd:d9:dd:c25:c25a:d00a:a668
1062c19:dd:d9:dd:c25:c25a:d00a:a669/1282c19:dd:d9:dd:c25:c25a:d00a:a669
1072c19:dd:d9:dd:c25:c25a:d00a:a66a/1282c19:dd:d9:dd:c25:c25a:d00a:a66a
1082c19:dd:d9:dd:c25:c25a:d00a:a66b/1282c19:dd:d9:dd:c25:c25a:d00a:a66b
1092c19:dd:d9:dd:c25:c25a:d00a:a66c/1282c19:dd:d9:dd:c25:c25a:d00a:a66c
1102c19:dd:d9:dd:c25:c25a:d00a:a66d/1282c19:dd:d9:dd:c25:c25a:d00a:a66d
1112c19:dd:d9:dd:c25:c25a:d00a:a66e/1282c19:dd:d9:dd:c25:c25a:d00a:a66e
1122c19:dd:d9:dd:c25:c25a:d00a:a66f/1282c19:dd:d9:dd:c25:c25a:d00a:a66f
1132c19:dd:d9:dd:c25:c25a:d00a:a670/1282c19:dd:d9:dd:c25:c25a:d00a:a670
1142c19:dd:d9:dd:c25:c25a:d00a:a671/1282c19:dd:d9:dd:c25:c25a:d00a:a671
1152c19:dd:d9:dd:c25:c25a:d00a:a672/1282c19:dd:d9:dd:c25:c25a:d00a:a672
1162c19:dd:d9:dd:c25:c25a:d00a:a673/1282c19:dd:d9:dd:c25:c25a:d00a:a673
1172c19:dd:d9:dd:c25:c25a:d00a:a674/1282c19:dd:d9:dd:c25:c25a:d00a:a674
1182c19:dd:d9:dd:c25:c25a:d00a:a675/1282c19:dd:d9:dd:c25:c25a:d00a:a675
1192c19:dd:d9:dd:c25:c25a:d00a:a676/1282c19:dd:d9:dd:c25:c25a:d00a:a676
1202c19:dd:d9:dd:c25:c25a:d00a:a677/1282c19:dd:d9:dd:c25:c25a:d00a:a677
1212c19:dd:d9:dd:c25:c25a:d00a:a678/1282c19:dd:d9:dd:c25:c25a:d00a:a678
1222c19:dd:d9:dd:c25:c25a:d00a:a679/1282c19:dd:d9:dd:c25:c25a:d00a:a679
1232c19:dd:d9:dd:c25:c25a:d00a:a67a/1282c19:dd:d9:dd:c25:c25a:d00a:a67a
1242c19:dd:d9:dd:c25:c25a:d00a:a67b/1282c19:dd:d9:dd:c25:c25a:d00a:a67b
1252c19:dd:d9:dd:c25:c25a:d00a:a67c/1282c19:dd:d9:dd:c25:c25a:d00a:a67c
1262c19:dd:d9:dd:c25:c25a:d00a:a67d/1282c19:dd:d9:dd:c25:c25a:d00a:a67d
1272c19:dd:d9:dd:c25:c25a:d00a:a67e/1282c19:dd:d9:dd:c25:c25a:d00a:a67e
1282c19:dd:d9:dd:c25:c25a:d00a:a67f/1282c19:dd:d9:dd:c25:c25a:d00a:a67f
1292c19:dd:d9:dd:c25:c25a:d00a:a680/1282c19:dd:d9:dd:c25:c25a:d00a:a680
1302c19:dd:d9:dd:c25:c25a:d00a:a681/1282c19:dd:d9:dd:c25:c25a:d00a:a681
1312c19:dd:d9:dd:c25:c25a:d00a:a682/1282c19:dd:d9:dd:c25:c25a:d00a:a682
1322c19:dd:d9:dd:c25:c25a:d00a:a683/1282c19:dd:d9:dd:c25:c25a:d00a:a683
1332c19:dd:d9:dd:c25:c25a:d00a:a684/1282c19:dd:d9:dd:c25:c25a:d00a:a684
1342c19:dd:d9:dd:c25:c25a:d00a:a685/1282c19:dd:d9:dd:c25:c25a:d00a:a685
1352c19:dd:d9:dd:c25:c25a:d00a:a686/1282c19:dd:d9:dd:c25:c25a:d00a:a686
1362c19:dd:d9:dd:c25:c25a:d00a:a687/1282c19:dd:d9:dd:c25:c25a:d00a:a687
1372c19:dd:d9:dd:c25:c25a:d00a:a688/1282c19:dd:d9:dd:c25:c25a:d00a:a688
1382c19:dd:d9:dd:c25:c25a:d00a:a689/1282c19:dd:d9:dd:c25:c25a:d00a:a689
1392c19:dd:d9:dd:c25:c25a:d00a:a68a/1282c19:dd:d9:dd:c25:c25a:d00a:a68a
1402c19:dd:d9:dd:c25:c25a:d00a:a68b/1282c19:dd:d9:dd:c25:c25a:d00a:a68b
1412c19:dd:d9:dd:c25:c25a:d00a:a68c/1282c19:dd:d9:dd:c25:c25a:d00a:a68c
1422c19:dd:d9:dd:c25:c25a:d00a:a68d/1282c19:dd:d9:dd:c25:c25a:d00a:a68d
1432c19:dd:d9:dd:c25:c25a:d00a:a68e/1282c19:dd:d9:dd:c25:c25a:d00a:a68e
1442c19:dd:d9:dd:c25:c25a:d00a:a68f/1282c19:dd:d9:dd:c25:c25a:d00a:a68f
1452c19:dd:d9:dd:c25:c25a:d00a:a690/1282c19:dd:d9:dd:c25:c25a:d00a:a690
1462c19:dd:d9:dd:c25:c25a:d00a:a691/1282c19:dd:d9:dd:c25:c25a:d00a:a691
1472c19:dd:d9:dd:c25:c25a:d00a:a692/1282c19:dd:d9:dd:c25:c25a:d00a:a692
1482c19:dd:d9:dd:c25:c25a:d00a:a693/1282c19:dd:d9:dd:c25:c25a:d00a:a693
1492c19:dd:d9:dd:c25:c25a:d00a:a694/1282c19:dd:d9:dd:c25:c25a:d00a:a694
1502c19:dd:d9:dd:c25:c25a:d00a:a695/1282c19:dd:d9:dd:c25:c25a:d00a:a695
1512c19:dd:d9:dd:c25:c25a:d00a:a696/1282c19:dd:d9:dd:c25:c25a:d00a:a696
1522c19:dd:d9:dd:c25:c25a:d00a:a697/1282c19:dd:d9:dd:c25:c25a:d00a:a697
1532c19:dd:d9:dd:c25:c25a:d00a:a698/1282c19:dd:d9:dd:c25:c25a:d00a:a698
1542c19:dd:d9:dd:c25:c25a:d00a:a699/1282c19:dd:d9:dd:c25:c25a:d00a:a699
1552c19:dd:d9:dd:c25:c25a:d00a:a69a/1282c19:dd:d9:dd:c25:c25a:d00a:a69a
1562c19:dd:d9:dd:c25:c25a:d00a:a69b/1282c19:dd:d9:dd:c25:c25a:d00a:a69b
1572c19:dd:d9:dd:c25:c25a:d00a:a69c/1282c19:dd:d9:dd:c25:c25a:d00a:a69c
1582c19:dd:d9:dd:c25:c25a:d00a:a69d/1282c19:dd:d9:dd:c25:c25a:d00a:a69d
1592c19:dd:d9:dd:c25:c25a:d00a:a69e/1282c19:dd:d9:dd:c25:c25a:d00a:a69e
1602c19:dd:d9:dd:c25:c25a:d00a:a69f/1282c19:dd:d9:dd:c25:c25a:d00a:a69f
1612c19:dd:d9:dd:c25:c25a:d00a:a6a0/1282c19:dd:d9:dd:c25:c25a:d00a:a6a0
1622c19:dd:d9:dd:c25:c25a:d00a:a6a1/1282c19:dd:d9:dd:c25:c25a:d00a:a6a1
1632c19:dd:d9:dd:c25:c25a:d00a:a6a2/1282c19:dd:d9:dd:c25:c25a:d00a:a6a2
1642c19:dd:d9:dd:c25:c25a:d00a:a6a3/1282c19:dd:d9:dd:c25:c25a:d00a:a6a3
1652c19:dd:d9:dd:c25:c25a:d00a:a6a4/1282c19:dd:d9:dd:c25:c25a:d00a:a6a4
1662c19:dd:d9:dd:c25:c25a:d00a:a6a5/1282c19:dd:d9:dd:c25:c25a:d00a:a6a5
1672c19:dd:d9:dd:c25:c25a:d00a:a6a6/1282c19:dd:d9:dd:c25:c25a:d00a:a6a6
1682c19:dd:d9:dd:c25:c25a:d00a:a6a7/1282c19:dd:d9:dd:c25:c25a:d00a:a6a7
1692c19:dd:d9:dd:c25:c25a:d00a:a6a8/1282c19:dd:d9:dd:c25:c25a:d00a:a6a8
1702c19:dd:d9:dd:c25:c25a:d00a:a6a9/1282c19:dd:d9:dd:c25:c25a:d00a:a6a9
1712c19:dd:d9:dd:c25:c25a:d00a:a6aa/1282c19:dd:d9:dd:c25:c25a:d00a:a6aa
1722c19:dd:d9:dd:c25:c25a:d00a:a6ab/1282c19:dd:d9:dd:c25:c25a:d00a:a6ab
1732c19:dd:d9:dd:c25:c25a:d00a:a6ac/1282c19:dd:d9:dd:c25:c25a:d00a:a6ac
1742c19:dd:d9:dd:c25:c25a:d00a:a6ad/1282c19:dd:d9:dd:c25:c25a:d00a:a6ad
1752c19:dd:d9:dd:c25:c25a:d00a:a6ae/1282c19:dd:d9:dd:c25:c25a:d00a:a6ae
1762c19:dd:d9:dd:c25:c25a:d00a:a6af/1282c19:dd:d9:dd:c25:c25a:d00a:a6af
1772c19:dd:d9:dd:c25:c25a:d00a:a6b0/1282c19:dd:d9:dd:c25:c25a:d00a:a6b0
1782c19:dd:d9:dd:c25:c25a:d00a:a6b1/1282c19:dd:d9:dd:c25:c25a:d00a:a6b1
1792c19:dd:d9:dd:c25:c25a:d00a:a6b2/1282c19:dd:d9:dd:c25:c25a:d00a:a6b2
1802c19:dd:d9:dd:c25:c25a:d00a:a6b3/1282c19:dd:d9:dd:c25:c25a:d00a:a6b3
1812c19:dd:d9:dd:c25:c25a:d00a:a6b4/1282c19:dd:d9:dd:c25:c25a:d00a:a6b4
1822c19:dd:d9:dd:c25:c25a:d00a:a6b5/1282c19:dd:d9:dd:c25:c25a:d00a:a6b5
1832c19:dd:d9:dd:c25:c25a:d00a:a6b6/1282c19:dd:d9:dd:c25:c25a:d00a:a6b6
1842c19:dd:d9:dd:c25:c25a:d00a:a6b7/1282c19:dd:d9:dd:c25:c25a:d00a:a6b7
1852c19:dd:d9:dd:c25:c25a:d00a:a6b8/1282c19:dd:d9:dd:c25:c25a:d00a:a6b8
1862c19:dd:d9:dd:c25:c25a:d00a:a6b9/1282c19:dd:d9:dd:c25:c25a:d00a:a6b9
1872c19:dd:d9:dd:c25:c25a:d00a:a6ba/1282c19:dd:d9:dd:c25:c25a:d00a:a6ba
1882c19:dd:d9:dd:c25:c25a:d00a:a6bb/1282c19:dd:d9:dd:c25:c25a:d00a:a6bb
1892c19:dd:d9:dd:c25:c25a:d00a:a6bc/1282c19:dd:d9:dd:c25:c25a:d00a:a6bc
1902c19:dd:d9:dd:c25:c25a:d00a:a6bd/1282c19:dd:d9:dd:c25:c25a:d00a:a6bd
1912c19:dd:d9:dd:c25:c25a:d00a:a6be/1282c19:dd:d9:dd:c25:c25a:d00a:a6be
1922c19:dd:d9:dd:c25:c25a:d00a:a6bf/1282c19:dd:d9:dd:c25:c25a:d00a:a6bf
1932c19:dd:d9:dd:c25:c25a:d00a:a6c0/1282c19:dd:d9:dd:c25:c25a:d00a:a6c0
1942c19:dd:d9:dd:c25:c25a:d00a:a6c1/1282c19:dd:d9:dd:c25:c25a:d00a:a6c1
1952c19:dd:d9:dd:c25:c25a:d00a:a6c2/1282c19:dd:d9:dd:c25:c25a:d00a:a6c2
1962c19:dd:d9:dd:c25:c25a:d00a:a6c3/1282c19:dd:d9:dd:c25:c25a:d00a:a6c3
1972c19:dd:d9:dd:c25:c25a:d00a:a6c4/1282c19:dd:d9:dd:c25:c25a:d00a:a6c4
1982c19:dd:d9:dd:c25:c25a:d00a:a6c5/1282c19:dd:d9:dd:c25:c25a:d00a:a6c5
1992c19:dd:d9:dd:c25:c25a:d00a:a6c6/1282c19:dd:d9:dd:c25:c25a:d00a:a6c6
2002c19:dd:d9:dd:c25:c25a:d00a:a6c7/1282c19:dd:d9:dd:c25:c25a:d00a:a6c7
2012c19:dd:d9:dd:c25:c25a:d00a:a6c8/1282c19:dd:d9:dd:c25:c25a:d00a:a6c8
2022c19:dd:d9:dd:c25:c25a:d00a:a6c9/1282c19:dd:d9:dd:c25:c25a:d00a:a6c9
2032c19:dd:d9:dd:c25:c25a:d00a:a6ca/1282c19:dd:d9:dd:c25:c25a:d00a:a6ca
2042c19:dd:d9:dd:c25:c25a:d00a:a6cb/1282c19:dd:d9:dd:c25:c25a:d00a:a6cb
2052c19:dd:d9:dd:c25:c25a:d00a:a6cc/1282c19:dd:d9:dd:c25:c25a:d00a:a6cc
2062c19:dd:d9:dd:c25:c25a:d00a:a6cd/1282c19:dd:d9:dd:c25:c25a:d00a:a6cd
2072c19:dd:d9:dd:c25:c25a:d00a:a6ce/1282c19:dd:d9:dd:c25:c25a:d00a:a6ce
2082c19:dd:d9:dd:c25:c25a:d00a:a6cf/1282c19:dd:d9:dd:c25:c25a:d00a:a6cf
2092c19:dd:d9:dd:c25:c25a:d00a:a6d0/1282c19:dd:d9:dd:c25:c25a:d00a:a6d0
2102c19:dd:d9:dd:c25:c25a:d00a:a6d1/1282c19:dd:d9:dd:c25:c25a:d00a:a6d1
2112c19:dd:d9:dd:c25:c25a:d00a:a6d2/1282c19:dd:d9:dd:c25:c25a:d00a:a6d2
2122c19:dd:d9:dd:c25:c25a:d00a:a6d3/1282c19:dd:d9:dd:c25:c25a:d00a:a6d3
2132c19:dd:d9:dd:c25:c25a:d00a:a6d4/1282c19:dd:d9:dd:c25:c25a:d00a:a6d4
2142c19:dd:d9:dd:c25:c25a:d00a:a6d5/1282c19:dd:d9:dd:c25:c25a:d00a:a6d5
2152c19:dd:d9:dd:c25:c25a:d00a:a6d6/1282c19:dd:d9:dd:c25:c25a:d00a:a6d6
2162c19:dd:d9:dd:c25:c25a:d00a:a6d7/1282c19:dd:d9:dd:c25:c25a:d00a:a6d7
2172c19:dd:d9:dd:c25:c25a:d00a:a6d8/1282c19:dd:d9:dd:c25:c25a:d00a:a6d8
2182c19:dd:d9:dd:c25:c25a:d00a:a6d9/1282c19:dd:d9:dd:c25:c25a:d00a:a6d9
2192c19:dd:d9:dd:c25:c25a:d00a:a6da/1282c19:dd:d9:dd:c25:c25a:d00a:a6da
2202c19:dd:d9:dd:c25:c25a:d00a:a6db/1282c19:dd:d9:dd:c25:c25a:d00a:a6db
2212c19:dd:d9:dd:c25:c25a:d00a:a6dc/1282c19:dd:d9:dd:c25:c25a:d00a:a6dc
2222c19:dd:d9:dd:c25:c25a:d00a:a6dd/1282c19:dd:d9:dd:c25:c25a:d00a:a6dd
2232c19:dd:d9:dd:c25:c25a:d00a:a6de/1282c19:dd:d9:dd:c25:c25a:d00a:a6de
2242c19:dd:d9:dd:c25:c25a:d00a:a6df/1282c19:dd:d9:dd:c25:c25a:d00a:a6df
2252c19:dd:d9:dd:c25:c25a:d00a:a6e0/1282c19:dd:d9:dd:c25:c25a:d00a:a6e0
2262c19:dd:d9:dd:c25:c25a:d00a:a6e1/1282c19:dd:d9:dd:c25:c25a:d00a:a6e1
2272c19:dd:d9:dd:c25:c25a:d00a:a6e2/1282c19:dd:d9:dd:c25:c25a:d00a:a6e2
2282c19:dd:d9:dd:c25:c25a:d00a:a6e3/1282c19:dd:d9:dd:c25:c25a:d00a:a6e3
2292c19:dd:d9:dd:c25:c25a:d00a:a6e4/1282c19:dd:d9:dd:c25:c25a:d00a:a6e4
2302c19:dd:d9:dd:c25:c25a:d00a:a6e5/1282c19:dd:d9:dd:c25:c25a:d00a:a6e5
2312c19:dd:d9:dd:c25:c25a:d00a:a6e6/1282c19:dd:d9:dd:c25:c25a:d00a:a6e6
2322c19:dd:d9:dd:c25:c25a:d00a:a6e7/1282c19:dd:d9:dd:c25:c25a:d00a:a6e7
2332c19:dd:d9:dd:c25:c25a:d00a:a6e8/1282c19:dd:d9:dd:c25:c25a:d00a:a6e8
2342c19:dd:d9:dd:c25:c25a:d00a:a6e9/1282c19:dd:d9:dd:c25:c25a:d00a:a6e9
2352c19:dd:d9:dd:c25:c25a:d00a:a6ea/1282c19:dd:d9:dd:c25:c25a:d00a:a6ea
2362c19:dd:d9:dd:c25:c25a:d00a:a6eb/1282c19:dd:d9:dd:c25:c25a:d00a:a6eb
2372c19:dd:d9:dd:c25:c25a:d00a:a6ec/1282c19:dd:d9:dd:c25:c25a:d00a:a6ec
2382c19:dd:d9:dd:c25:c25a:d00a:a6ed/1282c19:dd:d9:dd:c25:c25a:d00a:a6ed
2392c19:dd:d9:dd:c25:c25a:d00a:a6ee/1282c19:dd:d9:dd:c25:c25a:d00a:a6ee
2402c19:dd:d9:dd:c25:c25a:d00a:a6ef/1282c19:dd:d9:dd:c25:c25a:d00a:a6ef
2412c19:dd:d9:dd:c25:c25a:d00a:a6f0/1282c19:dd:d9:dd:c25:c25a:d00a:a6f0
2422c19:dd:d9:dd:c25:c25a:d00a:a6f1/1282c19:dd:d9:dd:c25:c25a:d00a:a6f1
2432c19:dd:d9:dd:c25:c25a:d00a:a6f2/1282c19:dd:d9:dd:c25:c25a:d00a:a6f2
2442c19:dd:d9:dd:c25:c25a:d00a:a6f3/1282c19:dd:d9:dd:c25:c25a:d00a:a6f3
2452c19:dd:d9:dd:c25:c25a:d00a:a6f4/1282c19:dd:d9:dd:c25:c25a:d00a:a6f4
2462c19:dd:d9:dd:c25:c25a:d00a:a6f5/1282c19:dd:d9:dd:c25:c25a:d00a:a6f5
2472c19:dd:d9:dd:c25:c25a:d00a:a6f6/1282c19:dd:d9:dd:c25:c25a:d00a:a6f6
2482c19:dd:d9:dd:c25:c25a:d00a:a6f7/1282c19:dd:d9:dd:c25:c25a:d00a:a6f7
2492c19:dd:d9:dd:c25:c25a:d00a:a6f8/1282c19:dd:d9:dd:c25:c25a:d00a:a6f8
2502c19:dd:d9:dd:c25:c25a:d00a:a6f9/1282c19:dd:d9:dd:c25:c25a:d00a:a6f9
2512c19:dd:d9:dd:c25:c25a:d00a:a6fa/1282c19:dd:d9:dd:c25:c25a:d00a:a6fa
2522c19:dd:d9:dd:c25:c25a:d00a:a6fb/1282c19:dd:d9:dd:c25:c25a:d00a:a6fb
2532c19:dd:d9:dd:c25:c25a:d00a:a6fc/1282c19:dd:d9:dd:c25:c25a:d00a:a6fc
2542c19:dd:d9:dd:c25:c25a:d00a:a6fd/1282c19:dd:d9:dd:c25:c25a:d00a:a6fd
2552c19:dd:d9:dd:c25:c25a:d00a:a6fe/1282c19:dd:d9:dd:c25:c25a:d00a:a6fe
2562c19:dd:d9:dd:c25:c25a:d00a:a6ff/1282c19:dd:d9:dd:c25:c25a:d00a:a6ff

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.