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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:c25:c25:dd:dd:dd:2600/119
First address
2c19:dd:c25:c25:dd:dd:dd:2600
Last address
2c19:dd:c25:c25:dd:dd:dd:27ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:0c25:00dd:00dd:00dd:2600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
6.2.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
7.2.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.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:c25:c25:dd:dd:dd:2600/119 makes 512 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:c25:c25:dd:dd:dd:2600/1282c19:dd:c25:c25:dd:dd:dd:2600
22c19:dd:c25:c25:dd:dd:dd:2601/1282c19:dd:c25:c25:dd:dd:dd:2601
32c19:dd:c25:c25:dd:dd:dd:2602/1282c19:dd:c25:c25:dd:dd:dd:2602
42c19:dd:c25:c25:dd:dd:dd:2603/1282c19:dd:c25:c25:dd:dd:dd:2603
52c19:dd:c25:c25:dd:dd:dd:2604/1282c19:dd:c25:c25:dd:dd:dd:2604
62c19:dd:c25:c25:dd:dd:dd:2605/1282c19:dd:c25:c25:dd:dd:dd:2605
72c19:dd:c25:c25:dd:dd:dd:2606/1282c19:dd:c25:c25:dd:dd:dd:2606
82c19:dd:c25:c25:dd:dd:dd:2607/1282c19:dd:c25:c25:dd:dd:dd:2607
92c19:dd:c25:c25:dd:dd:dd:2608/1282c19:dd:c25:c25:dd:dd:dd:2608
102c19:dd:c25:c25:dd:dd:dd:2609/1282c19:dd:c25:c25:dd:dd:dd:2609
112c19:dd:c25:c25:dd:dd:dd:260a/1282c19:dd:c25:c25:dd:dd:dd:260a
122c19:dd:c25:c25:dd:dd:dd:260b/1282c19:dd:c25:c25:dd:dd:dd:260b
132c19:dd:c25:c25:dd:dd:dd:260c/1282c19:dd:c25:c25:dd:dd:dd:260c
142c19:dd:c25:c25:dd:dd:dd:260d/1282c19:dd:c25:c25:dd:dd:dd:260d
152c19:dd:c25:c25:dd:dd:dd:260e/1282c19:dd:c25:c25:dd:dd:dd:260e
162c19:dd:c25:c25:dd:dd:dd:260f/1282c19:dd:c25:c25:dd:dd:dd:260f
172c19:dd:c25:c25:dd:dd:dd:2610/1282c19:dd:c25:c25:dd:dd:dd:2610
182c19:dd:c25:c25:dd:dd:dd:2611/1282c19:dd:c25:c25:dd:dd:dd:2611
192c19:dd:c25:c25:dd:dd:dd:2612/1282c19:dd:c25:c25:dd:dd:dd:2612
202c19:dd:c25:c25:dd:dd:dd:2613/1282c19:dd:c25:c25:dd:dd:dd:2613
212c19:dd:c25:c25:dd:dd:dd:2614/1282c19:dd:c25:c25:dd:dd:dd:2614
222c19:dd:c25:c25:dd:dd:dd:2615/1282c19:dd:c25:c25:dd:dd:dd:2615
232c19:dd:c25:c25:dd:dd:dd:2616/1282c19:dd:c25:c25:dd:dd:dd:2616
242c19:dd:c25:c25:dd:dd:dd:2617/1282c19:dd:c25:c25:dd:dd:dd:2617
252c19:dd:c25:c25:dd:dd:dd:2618/1282c19:dd:c25:c25:dd:dd:dd:2618
262c19:dd:c25:c25:dd:dd:dd:2619/1282c19:dd:c25:c25:dd:dd:dd:2619
272c19:dd:c25:c25:dd:dd:dd:261a/1282c19:dd:c25:c25:dd:dd:dd:261a
282c19:dd:c25:c25:dd:dd:dd:261b/1282c19:dd:c25:c25:dd:dd:dd:261b
292c19:dd:c25:c25:dd:dd:dd:261c/1282c19:dd:c25:c25:dd:dd:dd:261c
302c19:dd:c25:c25:dd:dd:dd:261d/1282c19:dd:c25:c25:dd:dd:dd:261d
312c19:dd:c25:c25:dd:dd:dd:261e/1282c19:dd:c25:c25:dd:dd:dd:261e
322c19:dd:c25:c25:dd:dd:dd:261f/1282c19:dd:c25:c25:dd:dd:dd:261f
332c19:dd:c25:c25:dd:dd:dd:2620/1282c19:dd:c25:c25:dd:dd:dd:2620
342c19:dd:c25:c25:dd:dd:dd:2621/1282c19:dd:c25:c25:dd:dd:dd:2621
352c19:dd:c25:c25:dd:dd:dd:2622/1282c19:dd:c25:c25:dd:dd:dd:2622
362c19:dd:c25:c25:dd:dd:dd:2623/1282c19:dd:c25:c25:dd:dd:dd:2623
372c19:dd:c25:c25:dd:dd:dd:2624/1282c19:dd:c25:c25:dd:dd:dd:2624
382c19:dd:c25:c25:dd:dd:dd:2625/1282c19:dd:c25:c25:dd:dd:dd:2625
392c19:dd:c25:c25:dd:dd:dd:2626/1282c19:dd:c25:c25:dd:dd:dd:2626
402c19:dd:c25:c25:dd:dd:dd:2627/1282c19:dd:c25:c25:dd:dd:dd:2627
412c19:dd:c25:c25:dd:dd:dd:2628/1282c19:dd:c25:c25:dd:dd:dd:2628
422c19:dd:c25:c25:dd:dd:dd:2629/1282c19:dd:c25:c25:dd:dd:dd:2629
432c19:dd:c25:c25:dd:dd:dd:262a/1282c19:dd:c25:c25:dd:dd:dd:262a
442c19:dd:c25:c25:dd:dd:dd:262b/1282c19:dd:c25:c25:dd:dd:dd:262b
452c19:dd:c25:c25:dd:dd:dd:262c/1282c19:dd:c25:c25:dd:dd:dd:262c
462c19:dd:c25:c25:dd:dd:dd:262d/1282c19:dd:c25:c25:dd:dd:dd:262d
472c19:dd:c25:c25:dd:dd:dd:262e/1282c19:dd:c25:c25:dd:dd:dd:262e
482c19:dd:c25:c25:dd:dd:dd:262f/1282c19:dd:c25:c25:dd:dd:dd:262f
492c19:dd:c25:c25:dd:dd:dd:2630/1282c19:dd:c25:c25:dd:dd:dd:2630
502c19:dd:c25:c25:dd:dd:dd:2631/1282c19:dd:c25:c25:dd:dd:dd:2631
512c19:dd:c25:c25:dd:dd:dd:2632/1282c19:dd:c25:c25:dd:dd:dd:2632
522c19:dd:c25:c25:dd:dd:dd:2633/1282c19:dd:c25:c25:dd:dd:dd:2633
532c19:dd:c25:c25:dd:dd:dd:2634/1282c19:dd:c25:c25:dd:dd:dd:2634
542c19:dd:c25:c25:dd:dd:dd:2635/1282c19:dd:c25:c25:dd:dd:dd:2635
552c19:dd:c25:c25:dd:dd:dd:2636/1282c19:dd:c25:c25:dd:dd:dd:2636
562c19:dd:c25:c25:dd:dd:dd:2637/1282c19:dd:c25:c25:dd:dd:dd:2637
572c19:dd:c25:c25:dd:dd:dd:2638/1282c19:dd:c25:c25:dd:dd:dd:2638
582c19:dd:c25:c25:dd:dd:dd:2639/1282c19:dd:c25:c25:dd:dd:dd:2639
592c19:dd:c25:c25:dd:dd:dd:263a/1282c19:dd:c25:c25:dd:dd:dd:263a
602c19:dd:c25:c25:dd:dd:dd:263b/1282c19:dd:c25:c25:dd:dd:dd:263b
612c19:dd:c25:c25:dd:dd:dd:263c/1282c19:dd:c25:c25:dd:dd:dd:263c
622c19:dd:c25:c25:dd:dd:dd:263d/1282c19:dd:c25:c25:dd:dd:dd:263d
632c19:dd:c25:c25:dd:dd:dd:263e/1282c19:dd:c25:c25:dd:dd:dd:263e
642c19:dd:c25:c25:dd:dd:dd:263f/1282c19:dd:c25:c25:dd:dd:dd:263f
652c19:dd:c25:c25:dd:dd:dd:2640/1282c19:dd:c25:c25:dd:dd:dd:2640
662c19:dd:c25:c25:dd:dd:dd:2641/1282c19:dd:c25:c25:dd:dd:dd:2641
672c19:dd:c25:c25:dd:dd:dd:2642/1282c19:dd:c25:c25:dd:dd:dd:2642
682c19:dd:c25:c25:dd:dd:dd:2643/1282c19:dd:c25:c25:dd:dd:dd:2643
692c19:dd:c25:c25:dd:dd:dd:2644/1282c19:dd:c25:c25:dd:dd:dd:2644
702c19:dd:c25:c25:dd:dd:dd:2645/1282c19:dd:c25:c25:dd:dd:dd:2645
712c19:dd:c25:c25:dd:dd:dd:2646/1282c19:dd:c25:c25:dd:dd:dd:2646
722c19:dd:c25:c25:dd:dd:dd:2647/1282c19:dd:c25:c25:dd:dd:dd:2647
732c19:dd:c25:c25:dd:dd:dd:2648/1282c19:dd:c25:c25:dd:dd:dd:2648
742c19:dd:c25:c25:dd:dd:dd:2649/1282c19:dd:c25:c25:dd:dd:dd:2649
752c19:dd:c25:c25:dd:dd:dd:264a/1282c19:dd:c25:c25:dd:dd:dd:264a
762c19:dd:c25:c25:dd:dd:dd:264b/1282c19:dd:c25:c25:dd:dd:dd:264b
772c19:dd:c25:c25:dd:dd:dd:264c/1282c19:dd:c25:c25:dd:dd:dd:264c
782c19:dd:c25:c25:dd:dd:dd:264d/1282c19:dd:c25:c25:dd:dd:dd:264d
792c19:dd:c25:c25:dd:dd:dd:264e/1282c19:dd:c25:c25:dd:dd:dd:264e
802c19:dd:c25:c25:dd:dd:dd:264f/1282c19:dd:c25:c25:dd:dd:dd:264f
812c19:dd:c25:c25:dd:dd:dd:2650/1282c19:dd:c25:c25:dd:dd:dd:2650
822c19:dd:c25:c25:dd:dd:dd:2651/1282c19:dd:c25:c25:dd:dd:dd:2651
832c19:dd:c25:c25:dd:dd:dd:2652/1282c19:dd:c25:c25:dd:dd:dd:2652
842c19:dd:c25:c25:dd:dd:dd:2653/1282c19:dd:c25:c25:dd:dd:dd:2653
852c19:dd:c25:c25:dd:dd:dd:2654/1282c19:dd:c25:c25:dd:dd:dd:2654
862c19:dd:c25:c25:dd:dd:dd:2655/1282c19:dd:c25:c25:dd:dd:dd:2655
872c19:dd:c25:c25:dd:dd:dd:2656/1282c19:dd:c25:c25:dd:dd:dd:2656
882c19:dd:c25:c25:dd:dd:dd:2657/1282c19:dd:c25:c25:dd:dd:dd:2657
892c19:dd:c25:c25:dd:dd:dd:2658/1282c19:dd:c25:c25:dd:dd:dd:2658
902c19:dd:c25:c25:dd:dd:dd:2659/1282c19:dd:c25:c25:dd:dd:dd:2659
912c19:dd:c25:c25:dd:dd:dd:265a/1282c19:dd:c25:c25:dd:dd:dd:265a
922c19:dd:c25:c25:dd:dd:dd:265b/1282c19:dd:c25:c25:dd:dd:dd:265b
932c19:dd:c25:c25:dd:dd:dd:265c/1282c19:dd:c25:c25:dd:dd:dd:265c
942c19:dd:c25:c25:dd:dd:dd:265d/1282c19:dd:c25:c25:dd:dd:dd:265d
952c19:dd:c25:c25:dd:dd:dd:265e/1282c19:dd:c25:c25:dd:dd:dd:265e
962c19:dd:c25:c25:dd:dd:dd:265f/1282c19:dd:c25:c25:dd:dd:dd:265f
972c19:dd:c25:c25:dd:dd:dd:2660/1282c19:dd:c25:c25:dd:dd:dd:2660
982c19:dd:c25:c25:dd:dd:dd:2661/1282c19:dd:c25:c25:dd:dd:dd:2661
992c19:dd:c25:c25:dd:dd:dd:2662/1282c19:dd:c25:c25:dd:dd:dd:2662
1002c19:dd:c25:c25:dd:dd:dd:2663/1282c19:dd:c25:c25:dd:dd:dd:2663
1012c19:dd:c25:c25:dd:dd:dd:2664/1282c19:dd:c25:c25:dd:dd:dd:2664
1022c19:dd:c25:c25:dd:dd:dd:2665/1282c19:dd:c25:c25:dd:dd:dd:2665
1032c19:dd:c25:c25:dd:dd:dd:2666/1282c19:dd:c25:c25:dd:dd:dd:2666
1042c19:dd:c25:c25:dd:dd:dd:2667/1282c19:dd:c25:c25:dd:dd:dd:2667
1052c19:dd:c25:c25:dd:dd:dd:2668/1282c19:dd:c25:c25:dd:dd:dd:2668
1062c19:dd:c25:c25:dd:dd:dd:2669/1282c19:dd:c25:c25:dd:dd:dd:2669
1072c19:dd:c25:c25:dd:dd:dd:266a/1282c19:dd:c25:c25:dd:dd:dd:266a
1082c19:dd:c25:c25:dd:dd:dd:266b/1282c19:dd:c25:c25:dd:dd:dd:266b
1092c19:dd:c25:c25:dd:dd:dd:266c/1282c19:dd:c25:c25:dd:dd:dd:266c
1102c19:dd:c25:c25:dd:dd:dd:266d/1282c19:dd:c25:c25:dd:dd:dd:266d
1112c19:dd:c25:c25:dd:dd:dd:266e/1282c19:dd:c25:c25:dd:dd:dd:266e
1122c19:dd:c25:c25:dd:dd:dd:266f/1282c19:dd:c25:c25:dd:dd:dd:266f
1132c19:dd:c25:c25:dd:dd:dd:2670/1282c19:dd:c25:c25:dd:dd:dd:2670
1142c19:dd:c25:c25:dd:dd:dd:2671/1282c19:dd:c25:c25:dd:dd:dd:2671
1152c19:dd:c25:c25:dd:dd:dd:2672/1282c19:dd:c25:c25:dd:dd:dd:2672
1162c19:dd:c25:c25:dd:dd:dd:2673/1282c19:dd:c25:c25:dd:dd:dd:2673
1172c19:dd:c25:c25:dd:dd:dd:2674/1282c19:dd:c25:c25:dd:dd:dd:2674
1182c19:dd:c25:c25:dd:dd:dd:2675/1282c19:dd:c25:c25:dd:dd:dd:2675
1192c19:dd:c25:c25:dd:dd:dd:2676/1282c19:dd:c25:c25:dd:dd:dd:2676
1202c19:dd:c25:c25:dd:dd:dd:2677/1282c19:dd:c25:c25:dd:dd:dd:2677
1212c19:dd:c25:c25:dd:dd:dd:2678/1282c19:dd:c25:c25:dd:dd:dd:2678
1222c19:dd:c25:c25:dd:dd:dd:2679/1282c19:dd:c25:c25:dd:dd:dd:2679
1232c19:dd:c25:c25:dd:dd:dd:267a/1282c19:dd:c25:c25:dd:dd:dd:267a
1242c19:dd:c25:c25:dd:dd:dd:267b/1282c19:dd:c25:c25:dd:dd:dd:267b
1252c19:dd:c25:c25:dd:dd:dd:267c/1282c19:dd:c25:c25:dd:dd:dd:267c
1262c19:dd:c25:c25:dd:dd:dd:267d/1282c19:dd:c25:c25:dd:dd:dd:267d
1272c19:dd:c25:c25:dd:dd:dd:267e/1282c19:dd:c25:c25:dd:dd:dd:267e
1282c19:dd:c25:c25:dd:dd:dd:267f/1282c19:dd:c25:c25:dd:dd:dd:267f
1292c19:dd:c25:c25:dd:dd:dd:2680/1282c19:dd:c25:c25:dd:dd:dd:2680
1302c19:dd:c25:c25:dd:dd:dd:2681/1282c19:dd:c25:c25:dd:dd:dd:2681
1312c19:dd:c25:c25:dd:dd:dd:2682/1282c19:dd:c25:c25:dd:dd:dd:2682
1322c19:dd:c25:c25:dd:dd:dd:2683/1282c19:dd:c25:c25:dd:dd:dd:2683
1332c19:dd:c25:c25:dd:dd:dd:2684/1282c19:dd:c25:c25:dd:dd:dd:2684
1342c19:dd:c25:c25:dd:dd:dd:2685/1282c19:dd:c25:c25:dd:dd:dd:2685
1352c19:dd:c25:c25:dd:dd:dd:2686/1282c19:dd:c25:c25:dd:dd:dd:2686
1362c19:dd:c25:c25:dd:dd:dd:2687/1282c19:dd:c25:c25:dd:dd:dd:2687
1372c19:dd:c25:c25:dd:dd:dd:2688/1282c19:dd:c25:c25:dd:dd:dd:2688
1382c19:dd:c25:c25:dd:dd:dd:2689/1282c19:dd:c25:c25:dd:dd:dd:2689
1392c19:dd:c25:c25:dd:dd:dd:268a/1282c19:dd:c25:c25:dd:dd:dd:268a
1402c19:dd:c25:c25:dd:dd:dd:268b/1282c19:dd:c25:c25:dd:dd:dd:268b
1412c19:dd:c25:c25:dd:dd:dd:268c/1282c19:dd:c25:c25:dd:dd:dd:268c
1422c19:dd:c25:c25:dd:dd:dd:268d/1282c19:dd:c25:c25:dd:dd:dd:268d
1432c19:dd:c25:c25:dd:dd:dd:268e/1282c19:dd:c25:c25:dd:dd:dd:268e
1442c19:dd:c25:c25:dd:dd:dd:268f/1282c19:dd:c25:c25:dd:dd:dd:268f
1452c19:dd:c25:c25:dd:dd:dd:2690/1282c19:dd:c25:c25:dd:dd:dd:2690
1462c19:dd:c25:c25:dd:dd:dd:2691/1282c19:dd:c25:c25:dd:dd:dd:2691
1472c19:dd:c25:c25:dd:dd:dd:2692/1282c19:dd:c25:c25:dd:dd:dd:2692
1482c19:dd:c25:c25:dd:dd:dd:2693/1282c19:dd:c25:c25:dd:dd:dd:2693
1492c19:dd:c25:c25:dd:dd:dd:2694/1282c19:dd:c25:c25:dd:dd:dd:2694
1502c19:dd:c25:c25:dd:dd:dd:2695/1282c19:dd:c25:c25:dd:dd:dd:2695
1512c19:dd:c25:c25:dd:dd:dd:2696/1282c19:dd:c25:c25:dd:dd:dd:2696
1522c19:dd:c25:c25:dd:dd:dd:2697/1282c19:dd:c25:c25:dd:dd:dd:2697
1532c19:dd:c25:c25:dd:dd:dd:2698/1282c19:dd:c25:c25:dd:dd:dd:2698
1542c19:dd:c25:c25:dd:dd:dd:2699/1282c19:dd:c25:c25:dd:dd:dd:2699
1552c19:dd:c25:c25:dd:dd:dd:269a/1282c19:dd:c25:c25:dd:dd:dd:269a
1562c19:dd:c25:c25:dd:dd:dd:269b/1282c19:dd:c25:c25:dd:dd:dd:269b
1572c19:dd:c25:c25:dd:dd:dd:269c/1282c19:dd:c25:c25:dd:dd:dd:269c
1582c19:dd:c25:c25:dd:dd:dd:269d/1282c19:dd:c25:c25:dd:dd:dd:269d
1592c19:dd:c25:c25:dd:dd:dd:269e/1282c19:dd:c25:c25:dd:dd:dd:269e
1602c19:dd:c25:c25:dd:dd:dd:269f/1282c19:dd:c25:c25:dd:dd:dd:269f
1612c19:dd:c25:c25:dd:dd:dd:26a0/1282c19:dd:c25:c25:dd:dd:dd:26a0
1622c19:dd:c25:c25:dd:dd:dd:26a1/1282c19:dd:c25:c25:dd:dd:dd:26a1
1632c19:dd:c25:c25:dd:dd:dd:26a2/1282c19:dd:c25:c25:dd:dd:dd:26a2
1642c19:dd:c25:c25:dd:dd:dd:26a3/1282c19:dd:c25:c25:dd:dd:dd:26a3
1652c19:dd:c25:c25:dd:dd:dd:26a4/1282c19:dd:c25:c25:dd:dd:dd:26a4
1662c19:dd:c25:c25:dd:dd:dd:26a5/1282c19:dd:c25:c25:dd:dd:dd:26a5
1672c19:dd:c25:c25:dd:dd:dd:26a6/1282c19:dd:c25:c25:dd:dd:dd:26a6
1682c19:dd:c25:c25:dd:dd:dd:26a7/1282c19:dd:c25:c25:dd:dd:dd:26a7
1692c19:dd:c25:c25:dd:dd:dd:26a8/1282c19:dd:c25:c25:dd:dd:dd:26a8
1702c19:dd:c25:c25:dd:dd:dd:26a9/1282c19:dd:c25:c25:dd:dd:dd:26a9
1712c19:dd:c25:c25:dd:dd:dd:26aa/1282c19:dd:c25:c25:dd:dd:dd:26aa
1722c19:dd:c25:c25:dd:dd:dd:26ab/1282c19:dd:c25:c25:dd:dd:dd:26ab
1732c19:dd:c25:c25:dd:dd:dd:26ac/1282c19:dd:c25:c25:dd:dd:dd:26ac
1742c19:dd:c25:c25:dd:dd:dd:26ad/1282c19:dd:c25:c25:dd:dd:dd:26ad
1752c19:dd:c25:c25:dd:dd:dd:26ae/1282c19:dd:c25:c25:dd:dd:dd:26ae
1762c19:dd:c25:c25:dd:dd:dd:26af/1282c19:dd:c25:c25:dd:dd:dd:26af
1772c19:dd:c25:c25:dd:dd:dd:26b0/1282c19:dd:c25:c25:dd:dd:dd:26b0
1782c19:dd:c25:c25:dd:dd:dd:26b1/1282c19:dd:c25:c25:dd:dd:dd:26b1
1792c19:dd:c25:c25:dd:dd:dd:26b2/1282c19:dd:c25:c25:dd:dd:dd:26b2
1802c19:dd:c25:c25:dd:dd:dd:26b3/1282c19:dd:c25:c25:dd:dd:dd:26b3
1812c19:dd:c25:c25:dd:dd:dd:26b4/1282c19:dd:c25:c25:dd:dd:dd:26b4
1822c19:dd:c25:c25:dd:dd:dd:26b5/1282c19:dd:c25:c25:dd:dd:dd:26b5
1832c19:dd:c25:c25:dd:dd:dd:26b6/1282c19:dd:c25:c25:dd:dd:dd:26b6
1842c19:dd:c25:c25:dd:dd:dd:26b7/1282c19:dd:c25:c25:dd:dd:dd:26b7
1852c19:dd:c25:c25:dd:dd:dd:26b8/1282c19:dd:c25:c25:dd:dd:dd:26b8
1862c19:dd:c25:c25:dd:dd:dd:26b9/1282c19:dd:c25:c25:dd:dd:dd:26b9
1872c19:dd:c25:c25:dd:dd:dd:26ba/1282c19:dd:c25:c25:dd:dd:dd:26ba
1882c19:dd:c25:c25:dd:dd:dd:26bb/1282c19:dd:c25:c25:dd:dd:dd:26bb
1892c19:dd:c25:c25:dd:dd:dd:26bc/1282c19:dd:c25:c25:dd:dd:dd:26bc
1902c19:dd:c25:c25:dd:dd:dd:26bd/1282c19:dd:c25:c25:dd:dd:dd:26bd
1912c19:dd:c25:c25:dd:dd:dd:26be/1282c19:dd:c25:c25:dd:dd:dd:26be
1922c19:dd:c25:c25:dd:dd:dd:26bf/1282c19:dd:c25:c25:dd:dd:dd:26bf
1932c19:dd:c25:c25:dd:dd:dd:26c0/1282c19:dd:c25:c25:dd:dd:dd:26c0
1942c19:dd:c25:c25:dd:dd:dd:26c1/1282c19:dd:c25:c25:dd:dd:dd:26c1
1952c19:dd:c25:c25:dd:dd:dd:26c2/1282c19:dd:c25:c25:dd:dd:dd:26c2
1962c19:dd:c25:c25:dd:dd:dd:26c3/1282c19:dd:c25:c25:dd:dd:dd:26c3
1972c19:dd:c25:c25:dd:dd:dd:26c4/1282c19:dd:c25:c25:dd:dd:dd:26c4
1982c19:dd:c25:c25:dd:dd:dd:26c5/1282c19:dd:c25:c25:dd:dd:dd:26c5
1992c19:dd:c25:c25:dd:dd:dd:26c6/1282c19:dd:c25:c25:dd:dd:dd:26c6
2002c19:dd:c25:c25:dd:dd:dd:26c7/1282c19:dd:c25:c25:dd:dd:dd:26c7
2012c19:dd:c25:c25:dd:dd:dd:26c8/1282c19:dd:c25:c25:dd:dd:dd:26c8
2022c19:dd:c25:c25:dd:dd:dd:26c9/1282c19:dd:c25:c25:dd:dd:dd:26c9
2032c19:dd:c25:c25:dd:dd:dd:26ca/1282c19:dd:c25:c25:dd:dd:dd:26ca
2042c19:dd:c25:c25:dd:dd:dd:26cb/1282c19:dd:c25:c25:dd:dd:dd:26cb
2052c19:dd:c25:c25:dd:dd:dd:26cc/1282c19:dd:c25:c25:dd:dd:dd:26cc
2062c19:dd:c25:c25:dd:dd:dd:26cd/1282c19:dd:c25:c25:dd:dd:dd:26cd
2072c19:dd:c25:c25:dd:dd:dd:26ce/1282c19:dd:c25:c25:dd:dd:dd:26ce
2082c19:dd:c25:c25:dd:dd:dd:26cf/1282c19:dd:c25:c25:dd:dd:dd:26cf
2092c19:dd:c25:c25:dd:dd:dd:26d0/1282c19:dd:c25:c25:dd:dd:dd:26d0
2102c19:dd:c25:c25:dd:dd:dd:26d1/1282c19:dd:c25:c25:dd:dd:dd:26d1
2112c19:dd:c25:c25:dd:dd:dd:26d2/1282c19:dd:c25:c25:dd:dd:dd:26d2
2122c19:dd:c25:c25:dd:dd:dd:26d3/1282c19:dd:c25:c25:dd:dd:dd:26d3
2132c19:dd:c25:c25:dd:dd:dd:26d4/1282c19:dd:c25:c25:dd:dd:dd:26d4
2142c19:dd:c25:c25:dd:dd:dd:26d5/1282c19:dd:c25:c25:dd:dd:dd:26d5
2152c19:dd:c25:c25:dd:dd:dd:26d6/1282c19:dd:c25:c25:dd:dd:dd:26d6
2162c19:dd:c25:c25:dd:dd:dd:26d7/1282c19:dd:c25:c25:dd:dd:dd:26d7
2172c19:dd:c25:c25:dd:dd:dd:26d8/1282c19:dd:c25:c25:dd:dd:dd:26d8
2182c19:dd:c25:c25:dd:dd:dd:26d9/1282c19:dd:c25:c25:dd:dd:dd:26d9
2192c19:dd:c25:c25:dd:dd:dd:26da/1282c19:dd:c25:c25:dd:dd:dd:26da
2202c19:dd:c25:c25:dd:dd:dd:26db/1282c19:dd:c25:c25:dd:dd:dd:26db
2212c19:dd:c25:c25:dd:dd:dd:26dc/1282c19:dd:c25:c25:dd:dd:dd:26dc
2222c19:dd:c25:c25:dd:dd:dd:26dd/1282c19:dd:c25:c25:dd:dd:dd:26dd
2232c19:dd:c25:c25:dd:dd:dd:26de/1282c19:dd:c25:c25:dd:dd:dd:26de
2242c19:dd:c25:c25:dd:dd:dd:26df/1282c19:dd:c25:c25:dd:dd:dd:26df
2252c19:dd:c25:c25:dd:dd:dd:26e0/1282c19:dd:c25:c25:dd:dd:dd:26e0
2262c19:dd:c25:c25:dd:dd:dd:26e1/1282c19:dd:c25:c25:dd:dd:dd:26e1
2272c19:dd:c25:c25:dd:dd:dd:26e2/1282c19:dd:c25:c25:dd:dd:dd:26e2
2282c19:dd:c25:c25:dd:dd:dd:26e3/1282c19:dd:c25:c25:dd:dd:dd:26e3
2292c19:dd:c25:c25:dd:dd:dd:26e4/1282c19:dd:c25:c25:dd:dd:dd:26e4
2302c19:dd:c25:c25:dd:dd:dd:26e5/1282c19:dd:c25:c25:dd:dd:dd:26e5
2312c19:dd:c25:c25:dd:dd:dd:26e6/1282c19:dd:c25:c25:dd:dd:dd:26e6
2322c19:dd:c25:c25:dd:dd:dd:26e7/1282c19:dd:c25:c25:dd:dd:dd:26e7
2332c19:dd:c25:c25:dd:dd:dd:26e8/1282c19:dd:c25:c25:dd:dd:dd:26e8
2342c19:dd:c25:c25:dd:dd:dd:26e9/1282c19:dd:c25:c25:dd:dd:dd:26e9
2352c19:dd:c25:c25:dd:dd:dd:26ea/1282c19:dd:c25:c25:dd:dd:dd:26ea
2362c19:dd:c25:c25:dd:dd:dd:26eb/1282c19:dd:c25:c25:dd:dd:dd:26eb
2372c19:dd:c25:c25:dd:dd:dd:26ec/1282c19:dd:c25:c25:dd:dd:dd:26ec
2382c19:dd:c25:c25:dd:dd:dd:26ed/1282c19:dd:c25:c25:dd:dd:dd:26ed
2392c19:dd:c25:c25:dd:dd:dd:26ee/1282c19:dd:c25:c25:dd:dd:dd:26ee
2402c19:dd:c25:c25:dd:dd:dd:26ef/1282c19:dd:c25:c25:dd:dd:dd:26ef
2412c19:dd:c25:c25:dd:dd:dd:26f0/1282c19:dd:c25:c25:dd:dd:dd:26f0
2422c19:dd:c25:c25:dd:dd:dd:26f1/1282c19:dd:c25:c25:dd:dd:dd:26f1
2432c19:dd:c25:c25:dd:dd:dd:26f2/1282c19:dd:c25:c25:dd:dd:dd:26f2
2442c19:dd:c25:c25:dd:dd:dd:26f3/1282c19:dd:c25:c25:dd:dd:dd:26f3
2452c19:dd:c25:c25:dd:dd:dd:26f4/1282c19:dd:c25:c25:dd:dd:dd:26f4
2462c19:dd:c25:c25:dd:dd:dd:26f5/1282c19:dd:c25:c25:dd:dd:dd:26f5
2472c19:dd:c25:c25:dd:dd:dd:26f6/1282c19:dd:c25:c25:dd:dd:dd:26f6
2482c19:dd:c25:c25:dd:dd:dd:26f7/1282c19:dd:c25:c25:dd:dd:dd:26f7
2492c19:dd:c25:c25:dd:dd:dd:26f8/1282c19:dd:c25:c25:dd:dd:dd:26f8
2502c19:dd:c25:c25:dd:dd:dd:26f9/1282c19:dd:c25:c25:dd:dd:dd:26f9
2512c19:dd:c25:c25:dd:dd:dd:26fa/1282c19:dd:c25:c25:dd:dd:dd:26fa
2522c19:dd:c25:c25:dd:dd:dd:26fb/1282c19:dd:c25:c25:dd:dd:dd:26fb
2532c19:dd:c25:c25:dd:dd:dd:26fc/1282c19:dd:c25:c25:dd:dd:dd:26fc
2542c19:dd:c25:c25:dd:dd:dd:26fd/1282c19:dd:c25:c25:dd:dd:dd:26fd
2552c19:dd:c25:c25:dd:dd:dd:26fe/1282c19:dd:c25:c25:dd:dd:dd:26fe
2562c19:dd:c25:c25:dd:dd:dd:26ff/1282c19:dd:c25:c25:dd:dd:dd:26ff

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.