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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:c25b:d00a:2700/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:2700
Last address
2c19:dd:d9:dd:c25:c25b:d00a:27ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:2700
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.2.a.0.0.d.b.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:c25b:d00a:2700/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:2700/1282c19:dd:d9:dd:c25:c25b:d00a:2700
22c19:dd:d9:dd:c25:c25b:d00a:2701/1282c19:dd:d9:dd:c25:c25b:d00a:2701
32c19:dd:d9:dd:c25:c25b:d00a:2702/1282c19:dd:d9:dd:c25:c25b:d00a:2702
42c19:dd:d9:dd:c25:c25b:d00a:2703/1282c19:dd:d9:dd:c25:c25b:d00a:2703
52c19:dd:d9:dd:c25:c25b:d00a:2704/1282c19:dd:d9:dd:c25:c25b:d00a:2704
62c19:dd:d9:dd:c25:c25b:d00a:2705/1282c19:dd:d9:dd:c25:c25b:d00a:2705
72c19:dd:d9:dd:c25:c25b:d00a:2706/1282c19:dd:d9:dd:c25:c25b:d00a:2706
82c19:dd:d9:dd:c25:c25b:d00a:2707/1282c19:dd:d9:dd:c25:c25b:d00a:2707
92c19:dd:d9:dd:c25:c25b:d00a:2708/1282c19:dd:d9:dd:c25:c25b:d00a:2708
102c19:dd:d9:dd:c25:c25b:d00a:2709/1282c19:dd:d9:dd:c25:c25b:d00a:2709
112c19:dd:d9:dd:c25:c25b:d00a:270a/1282c19:dd:d9:dd:c25:c25b:d00a:270a
122c19:dd:d9:dd:c25:c25b:d00a:270b/1282c19:dd:d9:dd:c25:c25b:d00a:270b
132c19:dd:d9:dd:c25:c25b:d00a:270c/1282c19:dd:d9:dd:c25:c25b:d00a:270c
142c19:dd:d9:dd:c25:c25b:d00a:270d/1282c19:dd:d9:dd:c25:c25b:d00a:270d
152c19:dd:d9:dd:c25:c25b:d00a:270e/1282c19:dd:d9:dd:c25:c25b:d00a:270e
162c19:dd:d9:dd:c25:c25b:d00a:270f/1282c19:dd:d9:dd:c25:c25b:d00a:270f
172c19:dd:d9:dd:c25:c25b:d00a:2710/1282c19:dd:d9:dd:c25:c25b:d00a:2710
182c19:dd:d9:dd:c25:c25b:d00a:2711/1282c19:dd:d9:dd:c25:c25b:d00a:2711
192c19:dd:d9:dd:c25:c25b:d00a:2712/1282c19:dd:d9:dd:c25:c25b:d00a:2712
202c19:dd:d9:dd:c25:c25b:d00a:2713/1282c19:dd:d9:dd:c25:c25b:d00a:2713
212c19:dd:d9:dd:c25:c25b:d00a:2714/1282c19:dd:d9:dd:c25:c25b:d00a:2714
222c19:dd:d9:dd:c25:c25b:d00a:2715/1282c19:dd:d9:dd:c25:c25b:d00a:2715
232c19:dd:d9:dd:c25:c25b:d00a:2716/1282c19:dd:d9:dd:c25:c25b:d00a:2716
242c19:dd:d9:dd:c25:c25b:d00a:2717/1282c19:dd:d9:dd:c25:c25b:d00a:2717
252c19:dd:d9:dd:c25:c25b:d00a:2718/1282c19:dd:d9:dd:c25:c25b:d00a:2718
262c19:dd:d9:dd:c25:c25b:d00a:2719/1282c19:dd:d9:dd:c25:c25b:d00a:2719
272c19:dd:d9:dd:c25:c25b:d00a:271a/1282c19:dd:d9:dd:c25:c25b:d00a:271a
282c19:dd:d9:dd:c25:c25b:d00a:271b/1282c19:dd:d9:dd:c25:c25b:d00a:271b
292c19:dd:d9:dd:c25:c25b:d00a:271c/1282c19:dd:d9:dd:c25:c25b:d00a:271c
302c19:dd:d9:dd:c25:c25b:d00a:271d/1282c19:dd:d9:dd:c25:c25b:d00a:271d
312c19:dd:d9:dd:c25:c25b:d00a:271e/1282c19:dd:d9:dd:c25:c25b:d00a:271e
322c19:dd:d9:dd:c25:c25b:d00a:271f/1282c19:dd:d9:dd:c25:c25b:d00a:271f
332c19:dd:d9:dd:c25:c25b:d00a:2720/1282c19:dd:d9:dd:c25:c25b:d00a:2720
342c19:dd:d9:dd:c25:c25b:d00a:2721/1282c19:dd:d9:dd:c25:c25b:d00a:2721
352c19:dd:d9:dd:c25:c25b:d00a:2722/1282c19:dd:d9:dd:c25:c25b:d00a:2722
362c19:dd:d9:dd:c25:c25b:d00a:2723/1282c19:dd:d9:dd:c25:c25b:d00a:2723
372c19:dd:d9:dd:c25:c25b:d00a:2724/1282c19:dd:d9:dd:c25:c25b:d00a:2724
382c19:dd:d9:dd:c25:c25b:d00a:2725/1282c19:dd:d9:dd:c25:c25b:d00a:2725
392c19:dd:d9:dd:c25:c25b:d00a:2726/1282c19:dd:d9:dd:c25:c25b:d00a:2726
402c19:dd:d9:dd:c25:c25b:d00a:2727/1282c19:dd:d9:dd:c25:c25b:d00a:2727
412c19:dd:d9:dd:c25:c25b:d00a:2728/1282c19:dd:d9:dd:c25:c25b:d00a:2728
422c19:dd:d9:dd:c25:c25b:d00a:2729/1282c19:dd:d9:dd:c25:c25b:d00a:2729
432c19:dd:d9:dd:c25:c25b:d00a:272a/1282c19:dd:d9:dd:c25:c25b:d00a:272a
442c19:dd:d9:dd:c25:c25b:d00a:272b/1282c19:dd:d9:dd:c25:c25b:d00a:272b
452c19:dd:d9:dd:c25:c25b:d00a:272c/1282c19:dd:d9:dd:c25:c25b:d00a:272c
462c19:dd:d9:dd:c25:c25b:d00a:272d/1282c19:dd:d9:dd:c25:c25b:d00a:272d
472c19:dd:d9:dd:c25:c25b:d00a:272e/1282c19:dd:d9:dd:c25:c25b:d00a:272e
482c19:dd:d9:dd:c25:c25b:d00a:272f/1282c19:dd:d9:dd:c25:c25b:d00a:272f
492c19:dd:d9:dd:c25:c25b:d00a:2730/1282c19:dd:d9:dd:c25:c25b:d00a:2730
502c19:dd:d9:dd:c25:c25b:d00a:2731/1282c19:dd:d9:dd:c25:c25b:d00a:2731
512c19:dd:d9:dd:c25:c25b:d00a:2732/1282c19:dd:d9:dd:c25:c25b:d00a:2732
522c19:dd:d9:dd:c25:c25b:d00a:2733/1282c19:dd:d9:dd:c25:c25b:d00a:2733
532c19:dd:d9:dd:c25:c25b:d00a:2734/1282c19:dd:d9:dd:c25:c25b:d00a:2734
542c19:dd:d9:dd:c25:c25b:d00a:2735/1282c19:dd:d9:dd:c25:c25b:d00a:2735
552c19:dd:d9:dd:c25:c25b:d00a:2736/1282c19:dd:d9:dd:c25:c25b:d00a:2736
562c19:dd:d9:dd:c25:c25b:d00a:2737/1282c19:dd:d9:dd:c25:c25b:d00a:2737
572c19:dd:d9:dd:c25:c25b:d00a:2738/1282c19:dd:d9:dd:c25:c25b:d00a:2738
582c19:dd:d9:dd:c25:c25b:d00a:2739/1282c19:dd:d9:dd:c25:c25b:d00a:2739
592c19:dd:d9:dd:c25:c25b:d00a:273a/1282c19:dd:d9:dd:c25:c25b:d00a:273a
602c19:dd:d9:dd:c25:c25b:d00a:273b/1282c19:dd:d9:dd:c25:c25b:d00a:273b
612c19:dd:d9:dd:c25:c25b:d00a:273c/1282c19:dd:d9:dd:c25:c25b:d00a:273c
622c19:dd:d9:dd:c25:c25b:d00a:273d/1282c19:dd:d9:dd:c25:c25b:d00a:273d
632c19:dd:d9:dd:c25:c25b:d00a:273e/1282c19:dd:d9:dd:c25:c25b:d00a:273e
642c19:dd:d9:dd:c25:c25b:d00a:273f/1282c19:dd:d9:dd:c25:c25b:d00a:273f
652c19:dd:d9:dd:c25:c25b:d00a:2740/1282c19:dd:d9:dd:c25:c25b:d00a:2740
662c19:dd:d9:dd:c25:c25b:d00a:2741/1282c19:dd:d9:dd:c25:c25b:d00a:2741
672c19:dd:d9:dd:c25:c25b:d00a:2742/1282c19:dd:d9:dd:c25:c25b:d00a:2742
682c19:dd:d9:dd:c25:c25b:d00a:2743/1282c19:dd:d9:dd:c25:c25b:d00a:2743
692c19:dd:d9:dd:c25:c25b:d00a:2744/1282c19:dd:d9:dd:c25:c25b:d00a:2744
702c19:dd:d9:dd:c25:c25b:d00a:2745/1282c19:dd:d9:dd:c25:c25b:d00a:2745
712c19:dd:d9:dd:c25:c25b:d00a:2746/1282c19:dd:d9:dd:c25:c25b:d00a:2746
722c19:dd:d9:dd:c25:c25b:d00a:2747/1282c19:dd:d9:dd:c25:c25b:d00a:2747
732c19:dd:d9:dd:c25:c25b:d00a:2748/1282c19:dd:d9:dd:c25:c25b:d00a:2748
742c19:dd:d9:dd:c25:c25b:d00a:2749/1282c19:dd:d9:dd:c25:c25b:d00a:2749
752c19:dd:d9:dd:c25:c25b:d00a:274a/1282c19:dd:d9:dd:c25:c25b:d00a:274a
762c19:dd:d9:dd:c25:c25b:d00a:274b/1282c19:dd:d9:dd:c25:c25b:d00a:274b
772c19:dd:d9:dd:c25:c25b:d00a:274c/1282c19:dd:d9:dd:c25:c25b:d00a:274c
782c19:dd:d9:dd:c25:c25b:d00a:274d/1282c19:dd:d9:dd:c25:c25b:d00a:274d
792c19:dd:d9:dd:c25:c25b:d00a:274e/1282c19:dd:d9:dd:c25:c25b:d00a:274e
802c19:dd:d9:dd:c25:c25b:d00a:274f/1282c19:dd:d9:dd:c25:c25b:d00a:274f
812c19:dd:d9:dd:c25:c25b:d00a:2750/1282c19:dd:d9:dd:c25:c25b:d00a:2750
822c19:dd:d9:dd:c25:c25b:d00a:2751/1282c19:dd:d9:dd:c25:c25b:d00a:2751
832c19:dd:d9:dd:c25:c25b:d00a:2752/1282c19:dd:d9:dd:c25:c25b:d00a:2752
842c19:dd:d9:dd:c25:c25b:d00a:2753/1282c19:dd:d9:dd:c25:c25b:d00a:2753
852c19:dd:d9:dd:c25:c25b:d00a:2754/1282c19:dd:d9:dd:c25:c25b:d00a:2754
862c19:dd:d9:dd:c25:c25b:d00a:2755/1282c19:dd:d9:dd:c25:c25b:d00a:2755
872c19:dd:d9:dd:c25:c25b:d00a:2756/1282c19:dd:d9:dd:c25:c25b:d00a:2756
882c19:dd:d9:dd:c25:c25b:d00a:2757/1282c19:dd:d9:dd:c25:c25b:d00a:2757
892c19:dd:d9:dd:c25:c25b:d00a:2758/1282c19:dd:d9:dd:c25:c25b:d00a:2758
902c19:dd:d9:dd:c25:c25b:d00a:2759/1282c19:dd:d9:dd:c25:c25b:d00a:2759
912c19:dd:d9:dd:c25:c25b:d00a:275a/1282c19:dd:d9:dd:c25:c25b:d00a:275a
922c19:dd:d9:dd:c25:c25b:d00a:275b/1282c19:dd:d9:dd:c25:c25b:d00a:275b
932c19:dd:d9:dd:c25:c25b:d00a:275c/1282c19:dd:d9:dd:c25:c25b:d00a:275c
942c19:dd:d9:dd:c25:c25b:d00a:275d/1282c19:dd:d9:dd:c25:c25b:d00a:275d
952c19:dd:d9:dd:c25:c25b:d00a:275e/1282c19:dd:d9:dd:c25:c25b:d00a:275e
962c19:dd:d9:dd:c25:c25b:d00a:275f/1282c19:dd:d9:dd:c25:c25b:d00a:275f
972c19:dd:d9:dd:c25:c25b:d00a:2760/1282c19:dd:d9:dd:c25:c25b:d00a:2760
982c19:dd:d9:dd:c25:c25b:d00a:2761/1282c19:dd:d9:dd:c25:c25b:d00a:2761
992c19:dd:d9:dd:c25:c25b:d00a:2762/1282c19:dd:d9:dd:c25:c25b:d00a:2762
1002c19:dd:d9:dd:c25:c25b:d00a:2763/1282c19:dd:d9:dd:c25:c25b:d00a:2763
1012c19:dd:d9:dd:c25:c25b:d00a:2764/1282c19:dd:d9:dd:c25:c25b:d00a:2764
1022c19:dd:d9:dd:c25:c25b:d00a:2765/1282c19:dd:d9:dd:c25:c25b:d00a:2765
1032c19:dd:d9:dd:c25:c25b:d00a:2766/1282c19:dd:d9:dd:c25:c25b:d00a:2766
1042c19:dd:d9:dd:c25:c25b:d00a:2767/1282c19:dd:d9:dd:c25:c25b:d00a:2767
1052c19:dd:d9:dd:c25:c25b:d00a:2768/1282c19:dd:d9:dd:c25:c25b:d00a:2768
1062c19:dd:d9:dd:c25:c25b:d00a:2769/1282c19:dd:d9:dd:c25:c25b:d00a:2769
1072c19:dd:d9:dd:c25:c25b:d00a:276a/1282c19:dd:d9:dd:c25:c25b:d00a:276a
1082c19:dd:d9:dd:c25:c25b:d00a:276b/1282c19:dd:d9:dd:c25:c25b:d00a:276b
1092c19:dd:d9:dd:c25:c25b:d00a:276c/1282c19:dd:d9:dd:c25:c25b:d00a:276c
1102c19:dd:d9:dd:c25:c25b:d00a:276d/1282c19:dd:d9:dd:c25:c25b:d00a:276d
1112c19:dd:d9:dd:c25:c25b:d00a:276e/1282c19:dd:d9:dd:c25:c25b:d00a:276e
1122c19:dd:d9:dd:c25:c25b:d00a:276f/1282c19:dd:d9:dd:c25:c25b:d00a:276f
1132c19:dd:d9:dd:c25:c25b:d00a:2770/1282c19:dd:d9:dd:c25:c25b:d00a:2770
1142c19:dd:d9:dd:c25:c25b:d00a:2771/1282c19:dd:d9:dd:c25:c25b:d00a:2771
1152c19:dd:d9:dd:c25:c25b:d00a:2772/1282c19:dd:d9:dd:c25:c25b:d00a:2772
1162c19:dd:d9:dd:c25:c25b:d00a:2773/1282c19:dd:d9:dd:c25:c25b:d00a:2773
1172c19:dd:d9:dd:c25:c25b:d00a:2774/1282c19:dd:d9:dd:c25:c25b:d00a:2774
1182c19:dd:d9:dd:c25:c25b:d00a:2775/1282c19:dd:d9:dd:c25:c25b:d00a:2775
1192c19:dd:d9:dd:c25:c25b:d00a:2776/1282c19:dd:d9:dd:c25:c25b:d00a:2776
1202c19:dd:d9:dd:c25:c25b:d00a:2777/1282c19:dd:d9:dd:c25:c25b:d00a:2777
1212c19:dd:d9:dd:c25:c25b:d00a:2778/1282c19:dd:d9:dd:c25:c25b:d00a:2778
1222c19:dd:d9:dd:c25:c25b:d00a:2779/1282c19:dd:d9:dd:c25:c25b:d00a:2779
1232c19:dd:d9:dd:c25:c25b:d00a:277a/1282c19:dd:d9:dd:c25:c25b:d00a:277a
1242c19:dd:d9:dd:c25:c25b:d00a:277b/1282c19:dd:d9:dd:c25:c25b:d00a:277b
1252c19:dd:d9:dd:c25:c25b:d00a:277c/1282c19:dd:d9:dd:c25:c25b:d00a:277c
1262c19:dd:d9:dd:c25:c25b:d00a:277d/1282c19:dd:d9:dd:c25:c25b:d00a:277d
1272c19:dd:d9:dd:c25:c25b:d00a:277e/1282c19:dd:d9:dd:c25:c25b:d00a:277e
1282c19:dd:d9:dd:c25:c25b:d00a:277f/1282c19:dd:d9:dd:c25:c25b:d00a:277f
1292c19:dd:d9:dd:c25:c25b:d00a:2780/1282c19:dd:d9:dd:c25:c25b:d00a:2780
1302c19:dd:d9:dd:c25:c25b:d00a:2781/1282c19:dd:d9:dd:c25:c25b:d00a:2781
1312c19:dd:d9:dd:c25:c25b:d00a:2782/1282c19:dd:d9:dd:c25:c25b:d00a:2782
1322c19:dd:d9:dd:c25:c25b:d00a:2783/1282c19:dd:d9:dd:c25:c25b:d00a:2783
1332c19:dd:d9:dd:c25:c25b:d00a:2784/1282c19:dd:d9:dd:c25:c25b:d00a:2784
1342c19:dd:d9:dd:c25:c25b:d00a:2785/1282c19:dd:d9:dd:c25:c25b:d00a:2785
1352c19:dd:d9:dd:c25:c25b:d00a:2786/1282c19:dd:d9:dd:c25:c25b:d00a:2786
1362c19:dd:d9:dd:c25:c25b:d00a:2787/1282c19:dd:d9:dd:c25:c25b:d00a:2787
1372c19:dd:d9:dd:c25:c25b:d00a:2788/1282c19:dd:d9:dd:c25:c25b:d00a:2788
1382c19:dd:d9:dd:c25:c25b:d00a:2789/1282c19:dd:d9:dd:c25:c25b:d00a:2789
1392c19:dd:d9:dd:c25:c25b:d00a:278a/1282c19:dd:d9:dd:c25:c25b:d00a:278a
1402c19:dd:d9:dd:c25:c25b:d00a:278b/1282c19:dd:d9:dd:c25:c25b:d00a:278b
1412c19:dd:d9:dd:c25:c25b:d00a:278c/1282c19:dd:d9:dd:c25:c25b:d00a:278c
1422c19:dd:d9:dd:c25:c25b:d00a:278d/1282c19:dd:d9:dd:c25:c25b:d00a:278d
1432c19:dd:d9:dd:c25:c25b:d00a:278e/1282c19:dd:d9:dd:c25:c25b:d00a:278e
1442c19:dd:d9:dd:c25:c25b:d00a:278f/1282c19:dd:d9:dd:c25:c25b:d00a:278f
1452c19:dd:d9:dd:c25:c25b:d00a:2790/1282c19:dd:d9:dd:c25:c25b:d00a:2790
1462c19:dd:d9:dd:c25:c25b:d00a:2791/1282c19:dd:d9:dd:c25:c25b:d00a:2791
1472c19:dd:d9:dd:c25:c25b:d00a:2792/1282c19:dd:d9:dd:c25:c25b:d00a:2792
1482c19:dd:d9:dd:c25:c25b:d00a:2793/1282c19:dd:d9:dd:c25:c25b:d00a:2793
1492c19:dd:d9:dd:c25:c25b:d00a:2794/1282c19:dd:d9:dd:c25:c25b:d00a:2794
1502c19:dd:d9:dd:c25:c25b:d00a:2795/1282c19:dd:d9:dd:c25:c25b:d00a:2795
1512c19:dd:d9:dd:c25:c25b:d00a:2796/1282c19:dd:d9:dd:c25:c25b:d00a:2796
1522c19:dd:d9:dd:c25:c25b:d00a:2797/1282c19:dd:d9:dd:c25:c25b:d00a:2797
1532c19:dd:d9:dd:c25:c25b:d00a:2798/1282c19:dd:d9:dd:c25:c25b:d00a:2798
1542c19:dd:d9:dd:c25:c25b:d00a:2799/1282c19:dd:d9:dd:c25:c25b:d00a:2799
1552c19:dd:d9:dd:c25:c25b:d00a:279a/1282c19:dd:d9:dd:c25:c25b:d00a:279a
1562c19:dd:d9:dd:c25:c25b:d00a:279b/1282c19:dd:d9:dd:c25:c25b:d00a:279b
1572c19:dd:d9:dd:c25:c25b:d00a:279c/1282c19:dd:d9:dd:c25:c25b:d00a:279c
1582c19:dd:d9:dd:c25:c25b:d00a:279d/1282c19:dd:d9:dd:c25:c25b:d00a:279d
1592c19:dd:d9:dd:c25:c25b:d00a:279e/1282c19:dd:d9:dd:c25:c25b:d00a:279e
1602c19:dd:d9:dd:c25:c25b:d00a:279f/1282c19:dd:d9:dd:c25:c25b:d00a:279f
1612c19:dd:d9:dd:c25:c25b:d00a:27a0/1282c19:dd:d9:dd:c25:c25b:d00a:27a0
1622c19:dd:d9:dd:c25:c25b:d00a:27a1/1282c19:dd:d9:dd:c25:c25b:d00a:27a1
1632c19:dd:d9:dd:c25:c25b:d00a:27a2/1282c19:dd:d9:dd:c25:c25b:d00a:27a2
1642c19:dd:d9:dd:c25:c25b:d00a:27a3/1282c19:dd:d9:dd:c25:c25b:d00a:27a3
1652c19:dd:d9:dd:c25:c25b:d00a:27a4/1282c19:dd:d9:dd:c25:c25b:d00a:27a4
1662c19:dd:d9:dd:c25:c25b:d00a:27a5/1282c19:dd:d9:dd:c25:c25b:d00a:27a5
1672c19:dd:d9:dd:c25:c25b:d00a:27a6/1282c19:dd:d9:dd:c25:c25b:d00a:27a6
1682c19:dd:d9:dd:c25:c25b:d00a:27a7/1282c19:dd:d9:dd:c25:c25b:d00a:27a7
1692c19:dd:d9:dd:c25:c25b:d00a:27a8/1282c19:dd:d9:dd:c25:c25b:d00a:27a8
1702c19:dd:d9:dd:c25:c25b:d00a:27a9/1282c19:dd:d9:dd:c25:c25b:d00a:27a9
1712c19:dd:d9:dd:c25:c25b:d00a:27aa/1282c19:dd:d9:dd:c25:c25b:d00a:27aa
1722c19:dd:d9:dd:c25:c25b:d00a:27ab/1282c19:dd:d9:dd:c25:c25b:d00a:27ab
1732c19:dd:d9:dd:c25:c25b:d00a:27ac/1282c19:dd:d9:dd:c25:c25b:d00a:27ac
1742c19:dd:d9:dd:c25:c25b:d00a:27ad/1282c19:dd:d9:dd:c25:c25b:d00a:27ad
1752c19:dd:d9:dd:c25:c25b:d00a:27ae/1282c19:dd:d9:dd:c25:c25b:d00a:27ae
1762c19:dd:d9:dd:c25:c25b:d00a:27af/1282c19:dd:d9:dd:c25:c25b:d00a:27af
1772c19:dd:d9:dd:c25:c25b:d00a:27b0/1282c19:dd:d9:dd:c25:c25b:d00a:27b0
1782c19:dd:d9:dd:c25:c25b:d00a:27b1/1282c19:dd:d9:dd:c25:c25b:d00a:27b1
1792c19:dd:d9:dd:c25:c25b:d00a:27b2/1282c19:dd:d9:dd:c25:c25b:d00a:27b2
1802c19:dd:d9:dd:c25:c25b:d00a:27b3/1282c19:dd:d9:dd:c25:c25b:d00a:27b3
1812c19:dd:d9:dd:c25:c25b:d00a:27b4/1282c19:dd:d9:dd:c25:c25b:d00a:27b4
1822c19:dd:d9:dd:c25:c25b:d00a:27b5/1282c19:dd:d9:dd:c25:c25b:d00a:27b5
1832c19:dd:d9:dd:c25:c25b:d00a:27b6/1282c19:dd:d9:dd:c25:c25b:d00a:27b6
1842c19:dd:d9:dd:c25:c25b:d00a:27b7/1282c19:dd:d9:dd:c25:c25b:d00a:27b7
1852c19:dd:d9:dd:c25:c25b:d00a:27b8/1282c19:dd:d9:dd:c25:c25b:d00a:27b8
1862c19:dd:d9:dd:c25:c25b:d00a:27b9/1282c19:dd:d9:dd:c25:c25b:d00a:27b9
1872c19:dd:d9:dd:c25:c25b:d00a:27ba/1282c19:dd:d9:dd:c25:c25b:d00a:27ba
1882c19:dd:d9:dd:c25:c25b:d00a:27bb/1282c19:dd:d9:dd:c25:c25b:d00a:27bb
1892c19:dd:d9:dd:c25:c25b:d00a:27bc/1282c19:dd:d9:dd:c25:c25b:d00a:27bc
1902c19:dd:d9:dd:c25:c25b:d00a:27bd/1282c19:dd:d9:dd:c25:c25b:d00a:27bd
1912c19:dd:d9:dd:c25:c25b:d00a:27be/1282c19:dd:d9:dd:c25:c25b:d00a:27be
1922c19:dd:d9:dd:c25:c25b:d00a:27bf/1282c19:dd:d9:dd:c25:c25b:d00a:27bf
1932c19:dd:d9:dd:c25:c25b:d00a:27c0/1282c19:dd:d9:dd:c25:c25b:d00a:27c0
1942c19:dd:d9:dd:c25:c25b:d00a:27c1/1282c19:dd:d9:dd:c25:c25b:d00a:27c1
1952c19:dd:d9:dd:c25:c25b:d00a:27c2/1282c19:dd:d9:dd:c25:c25b:d00a:27c2
1962c19:dd:d9:dd:c25:c25b:d00a:27c3/1282c19:dd:d9:dd:c25:c25b:d00a:27c3
1972c19:dd:d9:dd:c25:c25b:d00a:27c4/1282c19:dd:d9:dd:c25:c25b:d00a:27c4
1982c19:dd:d9:dd:c25:c25b:d00a:27c5/1282c19:dd:d9:dd:c25:c25b:d00a:27c5
1992c19:dd:d9:dd:c25:c25b:d00a:27c6/1282c19:dd:d9:dd:c25:c25b:d00a:27c6
2002c19:dd:d9:dd:c25:c25b:d00a:27c7/1282c19:dd:d9:dd:c25:c25b:d00a:27c7
2012c19:dd:d9:dd:c25:c25b:d00a:27c8/1282c19:dd:d9:dd:c25:c25b:d00a:27c8
2022c19:dd:d9:dd:c25:c25b:d00a:27c9/1282c19:dd:d9:dd:c25:c25b:d00a:27c9
2032c19:dd:d9:dd:c25:c25b:d00a:27ca/1282c19:dd:d9:dd:c25:c25b:d00a:27ca
2042c19:dd:d9:dd:c25:c25b:d00a:27cb/1282c19:dd:d9:dd:c25:c25b:d00a:27cb
2052c19:dd:d9:dd:c25:c25b:d00a:27cc/1282c19:dd:d9:dd:c25:c25b:d00a:27cc
2062c19:dd:d9:dd:c25:c25b:d00a:27cd/1282c19:dd:d9:dd:c25:c25b:d00a:27cd
2072c19:dd:d9:dd:c25:c25b:d00a:27ce/1282c19:dd:d9:dd:c25:c25b:d00a:27ce
2082c19:dd:d9:dd:c25:c25b:d00a:27cf/1282c19:dd:d9:dd:c25:c25b:d00a:27cf
2092c19:dd:d9:dd:c25:c25b:d00a:27d0/1282c19:dd:d9:dd:c25:c25b:d00a:27d0
2102c19:dd:d9:dd:c25:c25b:d00a:27d1/1282c19:dd:d9:dd:c25:c25b:d00a:27d1
2112c19:dd:d9:dd:c25:c25b:d00a:27d2/1282c19:dd:d9:dd:c25:c25b:d00a:27d2
2122c19:dd:d9:dd:c25:c25b:d00a:27d3/1282c19:dd:d9:dd:c25:c25b:d00a:27d3
2132c19:dd:d9:dd:c25:c25b:d00a:27d4/1282c19:dd:d9:dd:c25:c25b:d00a:27d4
2142c19:dd:d9:dd:c25:c25b:d00a:27d5/1282c19:dd:d9:dd:c25:c25b:d00a:27d5
2152c19:dd:d9:dd:c25:c25b:d00a:27d6/1282c19:dd:d9:dd:c25:c25b:d00a:27d6
2162c19:dd:d9:dd:c25:c25b:d00a:27d7/1282c19:dd:d9:dd:c25:c25b:d00a:27d7
2172c19:dd:d9:dd:c25:c25b:d00a:27d8/1282c19:dd:d9:dd:c25:c25b:d00a:27d8
2182c19:dd:d9:dd:c25:c25b:d00a:27d9/1282c19:dd:d9:dd:c25:c25b:d00a:27d9
2192c19:dd:d9:dd:c25:c25b:d00a:27da/1282c19:dd:d9:dd:c25:c25b:d00a:27da
2202c19:dd:d9:dd:c25:c25b:d00a:27db/1282c19:dd:d9:dd:c25:c25b:d00a:27db
2212c19:dd:d9:dd:c25:c25b:d00a:27dc/1282c19:dd:d9:dd:c25:c25b:d00a:27dc
2222c19:dd:d9:dd:c25:c25b:d00a:27dd/1282c19:dd:d9:dd:c25:c25b:d00a:27dd
2232c19:dd:d9:dd:c25:c25b:d00a:27de/1282c19:dd:d9:dd:c25:c25b:d00a:27de
2242c19:dd:d9:dd:c25:c25b:d00a:27df/1282c19:dd:d9:dd:c25:c25b:d00a:27df
2252c19:dd:d9:dd:c25:c25b:d00a:27e0/1282c19:dd:d9:dd:c25:c25b:d00a:27e0
2262c19:dd:d9:dd:c25:c25b:d00a:27e1/1282c19:dd:d9:dd:c25:c25b:d00a:27e1
2272c19:dd:d9:dd:c25:c25b:d00a:27e2/1282c19:dd:d9:dd:c25:c25b:d00a:27e2
2282c19:dd:d9:dd:c25:c25b:d00a:27e3/1282c19:dd:d9:dd:c25:c25b:d00a:27e3
2292c19:dd:d9:dd:c25:c25b:d00a:27e4/1282c19:dd:d9:dd:c25:c25b:d00a:27e4
2302c19:dd:d9:dd:c25:c25b:d00a:27e5/1282c19:dd:d9:dd:c25:c25b:d00a:27e5
2312c19:dd:d9:dd:c25:c25b:d00a:27e6/1282c19:dd:d9:dd:c25:c25b:d00a:27e6
2322c19:dd:d9:dd:c25:c25b:d00a:27e7/1282c19:dd:d9:dd:c25:c25b:d00a:27e7
2332c19:dd:d9:dd:c25:c25b:d00a:27e8/1282c19:dd:d9:dd:c25:c25b:d00a:27e8
2342c19:dd:d9:dd:c25:c25b:d00a:27e9/1282c19:dd:d9:dd:c25:c25b:d00a:27e9
2352c19:dd:d9:dd:c25:c25b:d00a:27ea/1282c19:dd:d9:dd:c25:c25b:d00a:27ea
2362c19:dd:d9:dd:c25:c25b:d00a:27eb/1282c19:dd:d9:dd:c25:c25b:d00a:27eb
2372c19:dd:d9:dd:c25:c25b:d00a:27ec/1282c19:dd:d9:dd:c25:c25b:d00a:27ec
2382c19:dd:d9:dd:c25:c25b:d00a:27ed/1282c19:dd:d9:dd:c25:c25b:d00a:27ed
2392c19:dd:d9:dd:c25:c25b:d00a:27ee/1282c19:dd:d9:dd:c25:c25b:d00a:27ee
2402c19:dd:d9:dd:c25:c25b:d00a:27ef/1282c19:dd:d9:dd:c25:c25b:d00a:27ef
2412c19:dd:d9:dd:c25:c25b:d00a:27f0/1282c19:dd:d9:dd:c25:c25b:d00a:27f0
2422c19:dd:d9:dd:c25:c25b:d00a:27f1/1282c19:dd:d9:dd:c25:c25b:d00a:27f1
2432c19:dd:d9:dd:c25:c25b:d00a:27f2/1282c19:dd:d9:dd:c25:c25b:d00a:27f2
2442c19:dd:d9:dd:c25:c25b:d00a:27f3/1282c19:dd:d9:dd:c25:c25b:d00a:27f3
2452c19:dd:d9:dd:c25:c25b:d00a:27f4/1282c19:dd:d9:dd:c25:c25b:d00a:27f4
2462c19:dd:d9:dd:c25:c25b:d00a:27f5/1282c19:dd:d9:dd:c25:c25b:d00a:27f5
2472c19:dd:d9:dd:c25:c25b:d00a:27f6/1282c19:dd:d9:dd:c25:c25b:d00a:27f6
2482c19:dd:d9:dd:c25:c25b:d00a:27f7/1282c19:dd:d9:dd:c25:c25b:d00a:27f7
2492c19:dd:d9:dd:c25:c25b:d00a:27f8/1282c19:dd:d9:dd:c25:c25b:d00a:27f8
2502c19:dd:d9:dd:c25:c25b:d00a:27f9/1282c19:dd:d9:dd:c25:c25b:d00a:27f9
2512c19:dd:d9:dd:c25:c25b:d00a:27fa/1282c19:dd:d9:dd:c25:c25b:d00a:27fa
2522c19:dd:d9:dd:c25:c25b:d00a:27fb/1282c19:dd:d9:dd:c25:c25b:d00a:27fb
2532c19:dd:d9:dd:c25:c25b:d00a:27fc/1282c19:dd:d9:dd:c25:c25b:d00a:27fc
2542c19:dd:d9:dd:c25:c25b:d00a:27fd/1282c19:dd:d9:dd:c25:c25b:d00a:27fd
2552c19:dd:d9:dd:c25:c25b:d00a:27fe/1282c19:dd:d9:dd:c25:c25b:d00a:27fe
2562c19:dd:d9:dd:c25:c25b:d00a:27ff/1282c19:dd:d9:dd:c25:c25b:d00a:27ff

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.