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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:3600/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:3600
Last address
2c19:dd:d9:dd:c25:c25a:d00a:36ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:3600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.3.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:3600/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:3600/1282c19:dd:d9:dd:c25:c25a:d00a:3600
22c19:dd:d9:dd:c25:c25a:d00a:3601/1282c19:dd:d9:dd:c25:c25a:d00a:3601
32c19:dd:d9:dd:c25:c25a:d00a:3602/1282c19:dd:d9:dd:c25:c25a:d00a:3602
42c19:dd:d9:dd:c25:c25a:d00a:3603/1282c19:dd:d9:dd:c25:c25a:d00a:3603
52c19:dd:d9:dd:c25:c25a:d00a:3604/1282c19:dd:d9:dd:c25:c25a:d00a:3604
62c19:dd:d9:dd:c25:c25a:d00a:3605/1282c19:dd:d9:dd:c25:c25a:d00a:3605
72c19:dd:d9:dd:c25:c25a:d00a:3606/1282c19:dd:d9:dd:c25:c25a:d00a:3606
82c19:dd:d9:dd:c25:c25a:d00a:3607/1282c19:dd:d9:dd:c25:c25a:d00a:3607
92c19:dd:d9:dd:c25:c25a:d00a:3608/1282c19:dd:d9:dd:c25:c25a:d00a:3608
102c19:dd:d9:dd:c25:c25a:d00a:3609/1282c19:dd:d9:dd:c25:c25a:d00a:3609
112c19:dd:d9:dd:c25:c25a:d00a:360a/1282c19:dd:d9:dd:c25:c25a:d00a:360a
122c19:dd:d9:dd:c25:c25a:d00a:360b/1282c19:dd:d9:dd:c25:c25a:d00a:360b
132c19:dd:d9:dd:c25:c25a:d00a:360c/1282c19:dd:d9:dd:c25:c25a:d00a:360c
142c19:dd:d9:dd:c25:c25a:d00a:360d/1282c19:dd:d9:dd:c25:c25a:d00a:360d
152c19:dd:d9:dd:c25:c25a:d00a:360e/1282c19:dd:d9:dd:c25:c25a:d00a:360e
162c19:dd:d9:dd:c25:c25a:d00a:360f/1282c19:dd:d9:dd:c25:c25a:d00a:360f
172c19:dd:d9:dd:c25:c25a:d00a:3610/1282c19:dd:d9:dd:c25:c25a:d00a:3610
182c19:dd:d9:dd:c25:c25a:d00a:3611/1282c19:dd:d9:dd:c25:c25a:d00a:3611
192c19:dd:d9:dd:c25:c25a:d00a:3612/1282c19:dd:d9:dd:c25:c25a:d00a:3612
202c19:dd:d9:dd:c25:c25a:d00a:3613/1282c19:dd:d9:dd:c25:c25a:d00a:3613
212c19:dd:d9:dd:c25:c25a:d00a:3614/1282c19:dd:d9:dd:c25:c25a:d00a:3614
222c19:dd:d9:dd:c25:c25a:d00a:3615/1282c19:dd:d9:dd:c25:c25a:d00a:3615
232c19:dd:d9:dd:c25:c25a:d00a:3616/1282c19:dd:d9:dd:c25:c25a:d00a:3616
242c19:dd:d9:dd:c25:c25a:d00a:3617/1282c19:dd:d9:dd:c25:c25a:d00a:3617
252c19:dd:d9:dd:c25:c25a:d00a:3618/1282c19:dd:d9:dd:c25:c25a:d00a:3618
262c19:dd:d9:dd:c25:c25a:d00a:3619/1282c19:dd:d9:dd:c25:c25a:d00a:3619
272c19:dd:d9:dd:c25:c25a:d00a:361a/1282c19:dd:d9:dd:c25:c25a:d00a:361a
282c19:dd:d9:dd:c25:c25a:d00a:361b/1282c19:dd:d9:dd:c25:c25a:d00a:361b
292c19:dd:d9:dd:c25:c25a:d00a:361c/1282c19:dd:d9:dd:c25:c25a:d00a:361c
302c19:dd:d9:dd:c25:c25a:d00a:361d/1282c19:dd:d9:dd:c25:c25a:d00a:361d
312c19:dd:d9:dd:c25:c25a:d00a:361e/1282c19:dd:d9:dd:c25:c25a:d00a:361e
322c19:dd:d9:dd:c25:c25a:d00a:361f/1282c19:dd:d9:dd:c25:c25a:d00a:361f
332c19:dd:d9:dd:c25:c25a:d00a:3620/1282c19:dd:d9:dd:c25:c25a:d00a:3620
342c19:dd:d9:dd:c25:c25a:d00a:3621/1282c19:dd:d9:dd:c25:c25a:d00a:3621
352c19:dd:d9:dd:c25:c25a:d00a:3622/1282c19:dd:d9:dd:c25:c25a:d00a:3622
362c19:dd:d9:dd:c25:c25a:d00a:3623/1282c19:dd:d9:dd:c25:c25a:d00a:3623
372c19:dd:d9:dd:c25:c25a:d00a:3624/1282c19:dd:d9:dd:c25:c25a:d00a:3624
382c19:dd:d9:dd:c25:c25a:d00a:3625/1282c19:dd:d9:dd:c25:c25a:d00a:3625
392c19:dd:d9:dd:c25:c25a:d00a:3626/1282c19:dd:d9:dd:c25:c25a:d00a:3626
402c19:dd:d9:dd:c25:c25a:d00a:3627/1282c19:dd:d9:dd:c25:c25a:d00a:3627
412c19:dd:d9:dd:c25:c25a:d00a:3628/1282c19:dd:d9:dd:c25:c25a:d00a:3628
422c19:dd:d9:dd:c25:c25a:d00a:3629/1282c19:dd:d9:dd:c25:c25a:d00a:3629
432c19:dd:d9:dd:c25:c25a:d00a:362a/1282c19:dd:d9:dd:c25:c25a:d00a:362a
442c19:dd:d9:dd:c25:c25a:d00a:362b/1282c19:dd:d9:dd:c25:c25a:d00a:362b
452c19:dd:d9:dd:c25:c25a:d00a:362c/1282c19:dd:d9:dd:c25:c25a:d00a:362c
462c19:dd:d9:dd:c25:c25a:d00a:362d/1282c19:dd:d9:dd:c25:c25a:d00a:362d
472c19:dd:d9:dd:c25:c25a:d00a:362e/1282c19:dd:d9:dd:c25:c25a:d00a:362e
482c19:dd:d9:dd:c25:c25a:d00a:362f/1282c19:dd:d9:dd:c25:c25a:d00a:362f
492c19:dd:d9:dd:c25:c25a:d00a:3630/1282c19:dd:d9:dd:c25:c25a:d00a:3630
502c19:dd:d9:dd:c25:c25a:d00a:3631/1282c19:dd:d9:dd:c25:c25a:d00a:3631
512c19:dd:d9:dd:c25:c25a:d00a:3632/1282c19:dd:d9:dd:c25:c25a:d00a:3632
522c19:dd:d9:dd:c25:c25a:d00a:3633/1282c19:dd:d9:dd:c25:c25a:d00a:3633
532c19:dd:d9:dd:c25:c25a:d00a:3634/1282c19:dd:d9:dd:c25:c25a:d00a:3634
542c19:dd:d9:dd:c25:c25a:d00a:3635/1282c19:dd:d9:dd:c25:c25a:d00a:3635
552c19:dd:d9:dd:c25:c25a:d00a:3636/1282c19:dd:d9:dd:c25:c25a:d00a:3636
562c19:dd:d9:dd:c25:c25a:d00a:3637/1282c19:dd:d9:dd:c25:c25a:d00a:3637
572c19:dd:d9:dd:c25:c25a:d00a:3638/1282c19:dd:d9:dd:c25:c25a:d00a:3638
582c19:dd:d9:dd:c25:c25a:d00a:3639/1282c19:dd:d9:dd:c25:c25a:d00a:3639
592c19:dd:d9:dd:c25:c25a:d00a:363a/1282c19:dd:d9:dd:c25:c25a:d00a:363a
602c19:dd:d9:dd:c25:c25a:d00a:363b/1282c19:dd:d9:dd:c25:c25a:d00a:363b
612c19:dd:d9:dd:c25:c25a:d00a:363c/1282c19:dd:d9:dd:c25:c25a:d00a:363c
622c19:dd:d9:dd:c25:c25a:d00a:363d/1282c19:dd:d9:dd:c25:c25a:d00a:363d
632c19:dd:d9:dd:c25:c25a:d00a:363e/1282c19:dd:d9:dd:c25:c25a:d00a:363e
642c19:dd:d9:dd:c25:c25a:d00a:363f/1282c19:dd:d9:dd:c25:c25a:d00a:363f
652c19:dd:d9:dd:c25:c25a:d00a:3640/1282c19:dd:d9:dd:c25:c25a:d00a:3640
662c19:dd:d9:dd:c25:c25a:d00a:3641/1282c19:dd:d9:dd:c25:c25a:d00a:3641
672c19:dd:d9:dd:c25:c25a:d00a:3642/1282c19:dd:d9:dd:c25:c25a:d00a:3642
682c19:dd:d9:dd:c25:c25a:d00a:3643/1282c19:dd:d9:dd:c25:c25a:d00a:3643
692c19:dd:d9:dd:c25:c25a:d00a:3644/1282c19:dd:d9:dd:c25:c25a:d00a:3644
702c19:dd:d9:dd:c25:c25a:d00a:3645/1282c19:dd:d9:dd:c25:c25a:d00a:3645
712c19:dd:d9:dd:c25:c25a:d00a:3646/1282c19:dd:d9:dd:c25:c25a:d00a:3646
722c19:dd:d9:dd:c25:c25a:d00a:3647/1282c19:dd:d9:dd:c25:c25a:d00a:3647
732c19:dd:d9:dd:c25:c25a:d00a:3648/1282c19:dd:d9:dd:c25:c25a:d00a:3648
742c19:dd:d9:dd:c25:c25a:d00a:3649/1282c19:dd:d9:dd:c25:c25a:d00a:3649
752c19:dd:d9:dd:c25:c25a:d00a:364a/1282c19:dd:d9:dd:c25:c25a:d00a:364a
762c19:dd:d9:dd:c25:c25a:d00a:364b/1282c19:dd:d9:dd:c25:c25a:d00a:364b
772c19:dd:d9:dd:c25:c25a:d00a:364c/1282c19:dd:d9:dd:c25:c25a:d00a:364c
782c19:dd:d9:dd:c25:c25a:d00a:364d/1282c19:dd:d9:dd:c25:c25a:d00a:364d
792c19:dd:d9:dd:c25:c25a:d00a:364e/1282c19:dd:d9:dd:c25:c25a:d00a:364e
802c19:dd:d9:dd:c25:c25a:d00a:364f/1282c19:dd:d9:dd:c25:c25a:d00a:364f
812c19:dd:d9:dd:c25:c25a:d00a:3650/1282c19:dd:d9:dd:c25:c25a:d00a:3650
822c19:dd:d9:dd:c25:c25a:d00a:3651/1282c19:dd:d9:dd:c25:c25a:d00a:3651
832c19:dd:d9:dd:c25:c25a:d00a:3652/1282c19:dd:d9:dd:c25:c25a:d00a:3652
842c19:dd:d9:dd:c25:c25a:d00a:3653/1282c19:dd:d9:dd:c25:c25a:d00a:3653
852c19:dd:d9:dd:c25:c25a:d00a:3654/1282c19:dd:d9:dd:c25:c25a:d00a:3654
862c19:dd:d9:dd:c25:c25a:d00a:3655/1282c19:dd:d9:dd:c25:c25a:d00a:3655
872c19:dd:d9:dd:c25:c25a:d00a:3656/1282c19:dd:d9:dd:c25:c25a:d00a:3656
882c19:dd:d9:dd:c25:c25a:d00a:3657/1282c19:dd:d9:dd:c25:c25a:d00a:3657
892c19:dd:d9:dd:c25:c25a:d00a:3658/1282c19:dd:d9:dd:c25:c25a:d00a:3658
902c19:dd:d9:dd:c25:c25a:d00a:3659/1282c19:dd:d9:dd:c25:c25a:d00a:3659
912c19:dd:d9:dd:c25:c25a:d00a:365a/1282c19:dd:d9:dd:c25:c25a:d00a:365a
922c19:dd:d9:dd:c25:c25a:d00a:365b/1282c19:dd:d9:dd:c25:c25a:d00a:365b
932c19:dd:d9:dd:c25:c25a:d00a:365c/1282c19:dd:d9:dd:c25:c25a:d00a:365c
942c19:dd:d9:dd:c25:c25a:d00a:365d/1282c19:dd:d9:dd:c25:c25a:d00a:365d
952c19:dd:d9:dd:c25:c25a:d00a:365e/1282c19:dd:d9:dd:c25:c25a:d00a:365e
962c19:dd:d9:dd:c25:c25a:d00a:365f/1282c19:dd:d9:dd:c25:c25a:d00a:365f
972c19:dd:d9:dd:c25:c25a:d00a:3660/1282c19:dd:d9:dd:c25:c25a:d00a:3660
982c19:dd:d9:dd:c25:c25a:d00a:3661/1282c19:dd:d9:dd:c25:c25a:d00a:3661
992c19:dd:d9:dd:c25:c25a:d00a:3662/1282c19:dd:d9:dd:c25:c25a:d00a:3662
1002c19:dd:d9:dd:c25:c25a:d00a:3663/1282c19:dd:d9:dd:c25:c25a:d00a:3663
1012c19:dd:d9:dd:c25:c25a:d00a:3664/1282c19:dd:d9:dd:c25:c25a:d00a:3664
1022c19:dd:d9:dd:c25:c25a:d00a:3665/1282c19:dd:d9:dd:c25:c25a:d00a:3665
1032c19:dd:d9:dd:c25:c25a:d00a:3666/1282c19:dd:d9:dd:c25:c25a:d00a:3666
1042c19:dd:d9:dd:c25:c25a:d00a:3667/1282c19:dd:d9:dd:c25:c25a:d00a:3667
1052c19:dd:d9:dd:c25:c25a:d00a:3668/1282c19:dd:d9:dd:c25:c25a:d00a:3668
1062c19:dd:d9:dd:c25:c25a:d00a:3669/1282c19:dd:d9:dd:c25:c25a:d00a:3669
1072c19:dd:d9:dd:c25:c25a:d00a:366a/1282c19:dd:d9:dd:c25:c25a:d00a:366a
1082c19:dd:d9:dd:c25:c25a:d00a:366b/1282c19:dd:d9:dd:c25:c25a:d00a:366b
1092c19:dd:d9:dd:c25:c25a:d00a:366c/1282c19:dd:d9:dd:c25:c25a:d00a:366c
1102c19:dd:d9:dd:c25:c25a:d00a:366d/1282c19:dd:d9:dd:c25:c25a:d00a:366d
1112c19:dd:d9:dd:c25:c25a:d00a:366e/1282c19:dd:d9:dd:c25:c25a:d00a:366e
1122c19:dd:d9:dd:c25:c25a:d00a:366f/1282c19:dd:d9:dd:c25:c25a:d00a:366f
1132c19:dd:d9:dd:c25:c25a:d00a:3670/1282c19:dd:d9:dd:c25:c25a:d00a:3670
1142c19:dd:d9:dd:c25:c25a:d00a:3671/1282c19:dd:d9:dd:c25:c25a:d00a:3671
1152c19:dd:d9:dd:c25:c25a:d00a:3672/1282c19:dd:d9:dd:c25:c25a:d00a:3672
1162c19:dd:d9:dd:c25:c25a:d00a:3673/1282c19:dd:d9:dd:c25:c25a:d00a:3673
1172c19:dd:d9:dd:c25:c25a:d00a:3674/1282c19:dd:d9:dd:c25:c25a:d00a:3674
1182c19:dd:d9:dd:c25:c25a:d00a:3675/1282c19:dd:d9:dd:c25:c25a:d00a:3675
1192c19:dd:d9:dd:c25:c25a:d00a:3676/1282c19:dd:d9:dd:c25:c25a:d00a:3676
1202c19:dd:d9:dd:c25:c25a:d00a:3677/1282c19:dd:d9:dd:c25:c25a:d00a:3677
1212c19:dd:d9:dd:c25:c25a:d00a:3678/1282c19:dd:d9:dd:c25:c25a:d00a:3678
1222c19:dd:d9:dd:c25:c25a:d00a:3679/1282c19:dd:d9:dd:c25:c25a:d00a:3679
1232c19:dd:d9:dd:c25:c25a:d00a:367a/1282c19:dd:d9:dd:c25:c25a:d00a:367a
1242c19:dd:d9:dd:c25:c25a:d00a:367b/1282c19:dd:d9:dd:c25:c25a:d00a:367b
1252c19:dd:d9:dd:c25:c25a:d00a:367c/1282c19:dd:d9:dd:c25:c25a:d00a:367c
1262c19:dd:d9:dd:c25:c25a:d00a:367d/1282c19:dd:d9:dd:c25:c25a:d00a:367d
1272c19:dd:d9:dd:c25:c25a:d00a:367e/1282c19:dd:d9:dd:c25:c25a:d00a:367e
1282c19:dd:d9:dd:c25:c25a:d00a:367f/1282c19:dd:d9:dd:c25:c25a:d00a:367f
1292c19:dd:d9:dd:c25:c25a:d00a:3680/1282c19:dd:d9:dd:c25:c25a:d00a:3680
1302c19:dd:d9:dd:c25:c25a:d00a:3681/1282c19:dd:d9:dd:c25:c25a:d00a:3681
1312c19:dd:d9:dd:c25:c25a:d00a:3682/1282c19:dd:d9:dd:c25:c25a:d00a:3682
1322c19:dd:d9:dd:c25:c25a:d00a:3683/1282c19:dd:d9:dd:c25:c25a:d00a:3683
1332c19:dd:d9:dd:c25:c25a:d00a:3684/1282c19:dd:d9:dd:c25:c25a:d00a:3684
1342c19:dd:d9:dd:c25:c25a:d00a:3685/1282c19:dd:d9:dd:c25:c25a:d00a:3685
1352c19:dd:d9:dd:c25:c25a:d00a:3686/1282c19:dd:d9:dd:c25:c25a:d00a:3686
1362c19:dd:d9:dd:c25:c25a:d00a:3687/1282c19:dd:d9:dd:c25:c25a:d00a:3687
1372c19:dd:d9:dd:c25:c25a:d00a:3688/1282c19:dd:d9:dd:c25:c25a:d00a:3688
1382c19:dd:d9:dd:c25:c25a:d00a:3689/1282c19:dd:d9:dd:c25:c25a:d00a:3689
1392c19:dd:d9:dd:c25:c25a:d00a:368a/1282c19:dd:d9:dd:c25:c25a:d00a:368a
1402c19:dd:d9:dd:c25:c25a:d00a:368b/1282c19:dd:d9:dd:c25:c25a:d00a:368b
1412c19:dd:d9:dd:c25:c25a:d00a:368c/1282c19:dd:d9:dd:c25:c25a:d00a:368c
1422c19:dd:d9:dd:c25:c25a:d00a:368d/1282c19:dd:d9:dd:c25:c25a:d00a:368d
1432c19:dd:d9:dd:c25:c25a:d00a:368e/1282c19:dd:d9:dd:c25:c25a:d00a:368e
1442c19:dd:d9:dd:c25:c25a:d00a:368f/1282c19:dd:d9:dd:c25:c25a:d00a:368f
1452c19:dd:d9:dd:c25:c25a:d00a:3690/1282c19:dd:d9:dd:c25:c25a:d00a:3690
1462c19:dd:d9:dd:c25:c25a:d00a:3691/1282c19:dd:d9:dd:c25:c25a:d00a:3691
1472c19:dd:d9:dd:c25:c25a:d00a:3692/1282c19:dd:d9:dd:c25:c25a:d00a:3692
1482c19:dd:d9:dd:c25:c25a:d00a:3693/1282c19:dd:d9:dd:c25:c25a:d00a:3693
1492c19:dd:d9:dd:c25:c25a:d00a:3694/1282c19:dd:d9:dd:c25:c25a:d00a:3694
1502c19:dd:d9:dd:c25:c25a:d00a:3695/1282c19:dd:d9:dd:c25:c25a:d00a:3695
1512c19:dd:d9:dd:c25:c25a:d00a:3696/1282c19:dd:d9:dd:c25:c25a:d00a:3696
1522c19:dd:d9:dd:c25:c25a:d00a:3697/1282c19:dd:d9:dd:c25:c25a:d00a:3697
1532c19:dd:d9:dd:c25:c25a:d00a:3698/1282c19:dd:d9:dd:c25:c25a:d00a:3698
1542c19:dd:d9:dd:c25:c25a:d00a:3699/1282c19:dd:d9:dd:c25:c25a:d00a:3699
1552c19:dd:d9:dd:c25:c25a:d00a:369a/1282c19:dd:d9:dd:c25:c25a:d00a:369a
1562c19:dd:d9:dd:c25:c25a:d00a:369b/1282c19:dd:d9:dd:c25:c25a:d00a:369b
1572c19:dd:d9:dd:c25:c25a:d00a:369c/1282c19:dd:d9:dd:c25:c25a:d00a:369c
1582c19:dd:d9:dd:c25:c25a:d00a:369d/1282c19:dd:d9:dd:c25:c25a:d00a:369d
1592c19:dd:d9:dd:c25:c25a:d00a:369e/1282c19:dd:d9:dd:c25:c25a:d00a:369e
1602c19:dd:d9:dd:c25:c25a:d00a:369f/1282c19:dd:d9:dd:c25:c25a:d00a:369f
1612c19:dd:d9:dd:c25:c25a:d00a:36a0/1282c19:dd:d9:dd:c25:c25a:d00a:36a0
1622c19:dd:d9:dd:c25:c25a:d00a:36a1/1282c19:dd:d9:dd:c25:c25a:d00a:36a1
1632c19:dd:d9:dd:c25:c25a:d00a:36a2/1282c19:dd:d9:dd:c25:c25a:d00a:36a2
1642c19:dd:d9:dd:c25:c25a:d00a:36a3/1282c19:dd:d9:dd:c25:c25a:d00a:36a3
1652c19:dd:d9:dd:c25:c25a:d00a:36a4/1282c19:dd:d9:dd:c25:c25a:d00a:36a4
1662c19:dd:d9:dd:c25:c25a:d00a:36a5/1282c19:dd:d9:dd:c25:c25a:d00a:36a5
1672c19:dd:d9:dd:c25:c25a:d00a:36a6/1282c19:dd:d9:dd:c25:c25a:d00a:36a6
1682c19:dd:d9:dd:c25:c25a:d00a:36a7/1282c19:dd:d9:dd:c25:c25a:d00a:36a7
1692c19:dd:d9:dd:c25:c25a:d00a:36a8/1282c19:dd:d9:dd:c25:c25a:d00a:36a8
1702c19:dd:d9:dd:c25:c25a:d00a:36a9/1282c19:dd:d9:dd:c25:c25a:d00a:36a9
1712c19:dd:d9:dd:c25:c25a:d00a:36aa/1282c19:dd:d9:dd:c25:c25a:d00a:36aa
1722c19:dd:d9:dd:c25:c25a:d00a:36ab/1282c19:dd:d9:dd:c25:c25a:d00a:36ab
1732c19:dd:d9:dd:c25:c25a:d00a:36ac/1282c19:dd:d9:dd:c25:c25a:d00a:36ac
1742c19:dd:d9:dd:c25:c25a:d00a:36ad/1282c19:dd:d9:dd:c25:c25a:d00a:36ad
1752c19:dd:d9:dd:c25:c25a:d00a:36ae/1282c19:dd:d9:dd:c25:c25a:d00a:36ae
1762c19:dd:d9:dd:c25:c25a:d00a:36af/1282c19:dd:d9:dd:c25:c25a:d00a:36af
1772c19:dd:d9:dd:c25:c25a:d00a:36b0/1282c19:dd:d9:dd:c25:c25a:d00a:36b0
1782c19:dd:d9:dd:c25:c25a:d00a:36b1/1282c19:dd:d9:dd:c25:c25a:d00a:36b1
1792c19:dd:d9:dd:c25:c25a:d00a:36b2/1282c19:dd:d9:dd:c25:c25a:d00a:36b2
1802c19:dd:d9:dd:c25:c25a:d00a:36b3/1282c19:dd:d9:dd:c25:c25a:d00a:36b3
1812c19:dd:d9:dd:c25:c25a:d00a:36b4/1282c19:dd:d9:dd:c25:c25a:d00a:36b4
1822c19:dd:d9:dd:c25:c25a:d00a:36b5/1282c19:dd:d9:dd:c25:c25a:d00a:36b5
1832c19:dd:d9:dd:c25:c25a:d00a:36b6/1282c19:dd:d9:dd:c25:c25a:d00a:36b6
1842c19:dd:d9:dd:c25:c25a:d00a:36b7/1282c19:dd:d9:dd:c25:c25a:d00a:36b7
1852c19:dd:d9:dd:c25:c25a:d00a:36b8/1282c19:dd:d9:dd:c25:c25a:d00a:36b8
1862c19:dd:d9:dd:c25:c25a:d00a:36b9/1282c19:dd:d9:dd:c25:c25a:d00a:36b9
1872c19:dd:d9:dd:c25:c25a:d00a:36ba/1282c19:dd:d9:dd:c25:c25a:d00a:36ba
1882c19:dd:d9:dd:c25:c25a:d00a:36bb/1282c19:dd:d9:dd:c25:c25a:d00a:36bb
1892c19:dd:d9:dd:c25:c25a:d00a:36bc/1282c19:dd:d9:dd:c25:c25a:d00a:36bc
1902c19:dd:d9:dd:c25:c25a:d00a:36bd/1282c19:dd:d9:dd:c25:c25a:d00a:36bd
1912c19:dd:d9:dd:c25:c25a:d00a:36be/1282c19:dd:d9:dd:c25:c25a:d00a:36be
1922c19:dd:d9:dd:c25:c25a:d00a:36bf/1282c19:dd:d9:dd:c25:c25a:d00a:36bf
1932c19:dd:d9:dd:c25:c25a:d00a:36c0/1282c19:dd:d9:dd:c25:c25a:d00a:36c0
1942c19:dd:d9:dd:c25:c25a:d00a:36c1/1282c19:dd:d9:dd:c25:c25a:d00a:36c1
1952c19:dd:d9:dd:c25:c25a:d00a:36c2/1282c19:dd:d9:dd:c25:c25a:d00a:36c2
1962c19:dd:d9:dd:c25:c25a:d00a:36c3/1282c19:dd:d9:dd:c25:c25a:d00a:36c3
1972c19:dd:d9:dd:c25:c25a:d00a:36c4/1282c19:dd:d9:dd:c25:c25a:d00a:36c4
1982c19:dd:d9:dd:c25:c25a:d00a:36c5/1282c19:dd:d9:dd:c25:c25a:d00a:36c5
1992c19:dd:d9:dd:c25:c25a:d00a:36c6/1282c19:dd:d9:dd:c25:c25a:d00a:36c6
2002c19:dd:d9:dd:c25:c25a:d00a:36c7/1282c19:dd:d9:dd:c25:c25a:d00a:36c7
2012c19:dd:d9:dd:c25:c25a:d00a:36c8/1282c19:dd:d9:dd:c25:c25a:d00a:36c8
2022c19:dd:d9:dd:c25:c25a:d00a:36c9/1282c19:dd:d9:dd:c25:c25a:d00a:36c9
2032c19:dd:d9:dd:c25:c25a:d00a:36ca/1282c19:dd:d9:dd:c25:c25a:d00a:36ca
2042c19:dd:d9:dd:c25:c25a:d00a:36cb/1282c19:dd:d9:dd:c25:c25a:d00a:36cb
2052c19:dd:d9:dd:c25:c25a:d00a:36cc/1282c19:dd:d9:dd:c25:c25a:d00a:36cc
2062c19:dd:d9:dd:c25:c25a:d00a:36cd/1282c19:dd:d9:dd:c25:c25a:d00a:36cd
2072c19:dd:d9:dd:c25:c25a:d00a:36ce/1282c19:dd:d9:dd:c25:c25a:d00a:36ce
2082c19:dd:d9:dd:c25:c25a:d00a:36cf/1282c19:dd:d9:dd:c25:c25a:d00a:36cf
2092c19:dd:d9:dd:c25:c25a:d00a:36d0/1282c19:dd:d9:dd:c25:c25a:d00a:36d0
2102c19:dd:d9:dd:c25:c25a:d00a:36d1/1282c19:dd:d9:dd:c25:c25a:d00a:36d1
2112c19:dd:d9:dd:c25:c25a:d00a:36d2/1282c19:dd:d9:dd:c25:c25a:d00a:36d2
2122c19:dd:d9:dd:c25:c25a:d00a:36d3/1282c19:dd:d9:dd:c25:c25a:d00a:36d3
2132c19:dd:d9:dd:c25:c25a:d00a:36d4/1282c19:dd:d9:dd:c25:c25a:d00a:36d4
2142c19:dd:d9:dd:c25:c25a:d00a:36d5/1282c19:dd:d9:dd:c25:c25a:d00a:36d5
2152c19:dd:d9:dd:c25:c25a:d00a:36d6/1282c19:dd:d9:dd:c25:c25a:d00a:36d6
2162c19:dd:d9:dd:c25:c25a:d00a:36d7/1282c19:dd:d9:dd:c25:c25a:d00a:36d7
2172c19:dd:d9:dd:c25:c25a:d00a:36d8/1282c19:dd:d9:dd:c25:c25a:d00a:36d8
2182c19:dd:d9:dd:c25:c25a:d00a:36d9/1282c19:dd:d9:dd:c25:c25a:d00a:36d9
2192c19:dd:d9:dd:c25:c25a:d00a:36da/1282c19:dd:d9:dd:c25:c25a:d00a:36da
2202c19:dd:d9:dd:c25:c25a:d00a:36db/1282c19:dd:d9:dd:c25:c25a:d00a:36db
2212c19:dd:d9:dd:c25:c25a:d00a:36dc/1282c19:dd:d9:dd:c25:c25a:d00a:36dc
2222c19:dd:d9:dd:c25:c25a:d00a:36dd/1282c19:dd:d9:dd:c25:c25a:d00a:36dd
2232c19:dd:d9:dd:c25:c25a:d00a:36de/1282c19:dd:d9:dd:c25:c25a:d00a:36de
2242c19:dd:d9:dd:c25:c25a:d00a:36df/1282c19:dd:d9:dd:c25:c25a:d00a:36df
2252c19:dd:d9:dd:c25:c25a:d00a:36e0/1282c19:dd:d9:dd:c25:c25a:d00a:36e0
2262c19:dd:d9:dd:c25:c25a:d00a:36e1/1282c19:dd:d9:dd:c25:c25a:d00a:36e1
2272c19:dd:d9:dd:c25:c25a:d00a:36e2/1282c19:dd:d9:dd:c25:c25a:d00a:36e2
2282c19:dd:d9:dd:c25:c25a:d00a:36e3/1282c19:dd:d9:dd:c25:c25a:d00a:36e3
2292c19:dd:d9:dd:c25:c25a:d00a:36e4/1282c19:dd:d9:dd:c25:c25a:d00a:36e4
2302c19:dd:d9:dd:c25:c25a:d00a:36e5/1282c19:dd:d9:dd:c25:c25a:d00a:36e5
2312c19:dd:d9:dd:c25:c25a:d00a:36e6/1282c19:dd:d9:dd:c25:c25a:d00a:36e6
2322c19:dd:d9:dd:c25:c25a:d00a:36e7/1282c19:dd:d9:dd:c25:c25a:d00a:36e7
2332c19:dd:d9:dd:c25:c25a:d00a:36e8/1282c19:dd:d9:dd:c25:c25a:d00a:36e8
2342c19:dd:d9:dd:c25:c25a:d00a:36e9/1282c19:dd:d9:dd:c25:c25a:d00a:36e9
2352c19:dd:d9:dd:c25:c25a:d00a:36ea/1282c19:dd:d9:dd:c25:c25a:d00a:36ea
2362c19:dd:d9:dd:c25:c25a:d00a:36eb/1282c19:dd:d9:dd:c25:c25a:d00a:36eb
2372c19:dd:d9:dd:c25:c25a:d00a:36ec/1282c19:dd:d9:dd:c25:c25a:d00a:36ec
2382c19:dd:d9:dd:c25:c25a:d00a:36ed/1282c19:dd:d9:dd:c25:c25a:d00a:36ed
2392c19:dd:d9:dd:c25:c25a:d00a:36ee/1282c19:dd:d9:dd:c25:c25a:d00a:36ee
2402c19:dd:d9:dd:c25:c25a:d00a:36ef/1282c19:dd:d9:dd:c25:c25a:d00a:36ef
2412c19:dd:d9:dd:c25:c25a:d00a:36f0/1282c19:dd:d9:dd:c25:c25a:d00a:36f0
2422c19:dd:d9:dd:c25:c25a:d00a:36f1/1282c19:dd:d9:dd:c25:c25a:d00a:36f1
2432c19:dd:d9:dd:c25:c25a:d00a:36f2/1282c19:dd:d9:dd:c25:c25a:d00a:36f2
2442c19:dd:d9:dd:c25:c25a:d00a:36f3/1282c19:dd:d9:dd:c25:c25a:d00a:36f3
2452c19:dd:d9:dd:c25:c25a:d00a:36f4/1282c19:dd:d9:dd:c25:c25a:d00a:36f4
2462c19:dd:d9:dd:c25:c25a:d00a:36f5/1282c19:dd:d9:dd:c25:c25a:d00a:36f5
2472c19:dd:d9:dd:c25:c25a:d00a:36f6/1282c19:dd:d9:dd:c25:c25a:d00a:36f6
2482c19:dd:d9:dd:c25:c25a:d00a:36f7/1282c19:dd:d9:dd:c25:c25a:d00a:36f7
2492c19:dd:d9:dd:c25:c25a:d00a:36f8/1282c19:dd:d9:dd:c25:c25a:d00a:36f8
2502c19:dd:d9:dd:c25:c25a:d00a:36f9/1282c19:dd:d9:dd:c25:c25a:d00a:36f9
2512c19:dd:d9:dd:c25:c25a:d00a:36fa/1282c19:dd:d9:dd:c25:c25a:d00a:36fa
2522c19:dd:d9:dd:c25:c25a:d00a:36fb/1282c19:dd:d9:dd:c25:c25a:d00a:36fb
2532c19:dd:d9:dd:c25:c25a:d00a:36fc/1282c19:dd:d9:dd:c25:c25a:d00a:36fc
2542c19:dd:d9:dd:c25:c25a:d00a:36fd/1282c19:dd:d9:dd:c25:c25a:d00a:36fd
2552c19:dd:d9:dd:c25:c25a:d00a:36fe/1282c19:dd:d9:dd:c25:c25a:d00a:36fe
2562c19:dd:d9:dd:c25:c25a:d00a:36ff/1282c19:dd:d9:dd:c25:c25a:d00a:36ff

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.