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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:7600/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:7600
Last address
2c19:dd:d9:dd:c25:c25a:d00a:76ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:7600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.7.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:7600/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:7600/1282c19:dd:d9:dd:c25:c25a:d00a:7600
22c19:dd:d9:dd:c25:c25a:d00a:7601/1282c19:dd:d9:dd:c25:c25a:d00a:7601
32c19:dd:d9:dd:c25:c25a:d00a:7602/1282c19:dd:d9:dd:c25:c25a:d00a:7602
42c19:dd:d9:dd:c25:c25a:d00a:7603/1282c19:dd:d9:dd:c25:c25a:d00a:7603
52c19:dd:d9:dd:c25:c25a:d00a:7604/1282c19:dd:d9:dd:c25:c25a:d00a:7604
62c19:dd:d9:dd:c25:c25a:d00a:7605/1282c19:dd:d9:dd:c25:c25a:d00a:7605
72c19:dd:d9:dd:c25:c25a:d00a:7606/1282c19:dd:d9:dd:c25:c25a:d00a:7606
82c19:dd:d9:dd:c25:c25a:d00a:7607/1282c19:dd:d9:dd:c25:c25a:d00a:7607
92c19:dd:d9:dd:c25:c25a:d00a:7608/1282c19:dd:d9:dd:c25:c25a:d00a:7608
102c19:dd:d9:dd:c25:c25a:d00a:7609/1282c19:dd:d9:dd:c25:c25a:d00a:7609
112c19:dd:d9:dd:c25:c25a:d00a:760a/1282c19:dd:d9:dd:c25:c25a:d00a:760a
122c19:dd:d9:dd:c25:c25a:d00a:760b/1282c19:dd:d9:dd:c25:c25a:d00a:760b
132c19:dd:d9:dd:c25:c25a:d00a:760c/1282c19:dd:d9:dd:c25:c25a:d00a:760c
142c19:dd:d9:dd:c25:c25a:d00a:760d/1282c19:dd:d9:dd:c25:c25a:d00a:760d
152c19:dd:d9:dd:c25:c25a:d00a:760e/1282c19:dd:d9:dd:c25:c25a:d00a:760e
162c19:dd:d9:dd:c25:c25a:d00a:760f/1282c19:dd:d9:dd:c25:c25a:d00a:760f
172c19:dd:d9:dd:c25:c25a:d00a:7610/1282c19:dd:d9:dd:c25:c25a:d00a:7610
182c19:dd:d9:dd:c25:c25a:d00a:7611/1282c19:dd:d9:dd:c25:c25a:d00a:7611
192c19:dd:d9:dd:c25:c25a:d00a:7612/1282c19:dd:d9:dd:c25:c25a:d00a:7612
202c19:dd:d9:dd:c25:c25a:d00a:7613/1282c19:dd:d9:dd:c25:c25a:d00a:7613
212c19:dd:d9:dd:c25:c25a:d00a:7614/1282c19:dd:d9:dd:c25:c25a:d00a:7614
222c19:dd:d9:dd:c25:c25a:d00a:7615/1282c19:dd:d9:dd:c25:c25a:d00a:7615
232c19:dd:d9:dd:c25:c25a:d00a:7616/1282c19:dd:d9:dd:c25:c25a:d00a:7616
242c19:dd:d9:dd:c25:c25a:d00a:7617/1282c19:dd:d9:dd:c25:c25a:d00a:7617
252c19:dd:d9:dd:c25:c25a:d00a:7618/1282c19:dd:d9:dd:c25:c25a:d00a:7618
262c19:dd:d9:dd:c25:c25a:d00a:7619/1282c19:dd:d9:dd:c25:c25a:d00a:7619
272c19:dd:d9:dd:c25:c25a:d00a:761a/1282c19:dd:d9:dd:c25:c25a:d00a:761a
282c19:dd:d9:dd:c25:c25a:d00a:761b/1282c19:dd:d9:dd:c25:c25a:d00a:761b
292c19:dd:d9:dd:c25:c25a:d00a:761c/1282c19:dd:d9:dd:c25:c25a:d00a:761c
302c19:dd:d9:dd:c25:c25a:d00a:761d/1282c19:dd:d9:dd:c25:c25a:d00a:761d
312c19:dd:d9:dd:c25:c25a:d00a:761e/1282c19:dd:d9:dd:c25:c25a:d00a:761e
322c19:dd:d9:dd:c25:c25a:d00a:761f/1282c19:dd:d9:dd:c25:c25a:d00a:761f
332c19:dd:d9:dd:c25:c25a:d00a:7620/1282c19:dd:d9:dd:c25:c25a:d00a:7620
342c19:dd:d9:dd:c25:c25a:d00a:7621/1282c19:dd:d9:dd:c25:c25a:d00a:7621
352c19:dd:d9:dd:c25:c25a:d00a:7622/1282c19:dd:d9:dd:c25:c25a:d00a:7622
362c19:dd:d9:dd:c25:c25a:d00a:7623/1282c19:dd:d9:dd:c25:c25a:d00a:7623
372c19:dd:d9:dd:c25:c25a:d00a:7624/1282c19:dd:d9:dd:c25:c25a:d00a:7624
382c19:dd:d9:dd:c25:c25a:d00a:7625/1282c19:dd:d9:dd:c25:c25a:d00a:7625
392c19:dd:d9:dd:c25:c25a:d00a:7626/1282c19:dd:d9:dd:c25:c25a:d00a:7626
402c19:dd:d9:dd:c25:c25a:d00a:7627/1282c19:dd:d9:dd:c25:c25a:d00a:7627
412c19:dd:d9:dd:c25:c25a:d00a:7628/1282c19:dd:d9:dd:c25:c25a:d00a:7628
422c19:dd:d9:dd:c25:c25a:d00a:7629/1282c19:dd:d9:dd:c25:c25a:d00a:7629
432c19:dd:d9:dd:c25:c25a:d00a:762a/1282c19:dd:d9:dd:c25:c25a:d00a:762a
442c19:dd:d9:dd:c25:c25a:d00a:762b/1282c19:dd:d9:dd:c25:c25a:d00a:762b
452c19:dd:d9:dd:c25:c25a:d00a:762c/1282c19:dd:d9:dd:c25:c25a:d00a:762c
462c19:dd:d9:dd:c25:c25a:d00a:762d/1282c19:dd:d9:dd:c25:c25a:d00a:762d
472c19:dd:d9:dd:c25:c25a:d00a:762e/1282c19:dd:d9:dd:c25:c25a:d00a:762e
482c19:dd:d9:dd:c25:c25a:d00a:762f/1282c19:dd:d9:dd:c25:c25a:d00a:762f
492c19:dd:d9:dd:c25:c25a:d00a:7630/1282c19:dd:d9:dd:c25:c25a:d00a:7630
502c19:dd:d9:dd:c25:c25a:d00a:7631/1282c19:dd:d9:dd:c25:c25a:d00a:7631
512c19:dd:d9:dd:c25:c25a:d00a:7632/1282c19:dd:d9:dd:c25:c25a:d00a:7632
522c19:dd:d9:dd:c25:c25a:d00a:7633/1282c19:dd:d9:dd:c25:c25a:d00a:7633
532c19:dd:d9:dd:c25:c25a:d00a:7634/1282c19:dd:d9:dd:c25:c25a:d00a:7634
542c19:dd:d9:dd:c25:c25a:d00a:7635/1282c19:dd:d9:dd:c25:c25a:d00a:7635
552c19:dd:d9:dd:c25:c25a:d00a:7636/1282c19:dd:d9:dd:c25:c25a:d00a:7636
562c19:dd:d9:dd:c25:c25a:d00a:7637/1282c19:dd:d9:dd:c25:c25a:d00a:7637
572c19:dd:d9:dd:c25:c25a:d00a:7638/1282c19:dd:d9:dd:c25:c25a:d00a:7638
582c19:dd:d9:dd:c25:c25a:d00a:7639/1282c19:dd:d9:dd:c25:c25a:d00a:7639
592c19:dd:d9:dd:c25:c25a:d00a:763a/1282c19:dd:d9:dd:c25:c25a:d00a:763a
602c19:dd:d9:dd:c25:c25a:d00a:763b/1282c19:dd:d9:dd:c25:c25a:d00a:763b
612c19:dd:d9:dd:c25:c25a:d00a:763c/1282c19:dd:d9:dd:c25:c25a:d00a:763c
622c19:dd:d9:dd:c25:c25a:d00a:763d/1282c19:dd:d9:dd:c25:c25a:d00a:763d
632c19:dd:d9:dd:c25:c25a:d00a:763e/1282c19:dd:d9:dd:c25:c25a:d00a:763e
642c19:dd:d9:dd:c25:c25a:d00a:763f/1282c19:dd:d9:dd:c25:c25a:d00a:763f
652c19:dd:d9:dd:c25:c25a:d00a:7640/1282c19:dd:d9:dd:c25:c25a:d00a:7640
662c19:dd:d9:dd:c25:c25a:d00a:7641/1282c19:dd:d9:dd:c25:c25a:d00a:7641
672c19:dd:d9:dd:c25:c25a:d00a:7642/1282c19:dd:d9:dd:c25:c25a:d00a:7642
682c19:dd:d9:dd:c25:c25a:d00a:7643/1282c19:dd:d9:dd:c25:c25a:d00a:7643
692c19:dd:d9:dd:c25:c25a:d00a:7644/1282c19:dd:d9:dd:c25:c25a:d00a:7644
702c19:dd:d9:dd:c25:c25a:d00a:7645/1282c19:dd:d9:dd:c25:c25a:d00a:7645
712c19:dd:d9:dd:c25:c25a:d00a:7646/1282c19:dd:d9:dd:c25:c25a:d00a:7646
722c19:dd:d9:dd:c25:c25a:d00a:7647/1282c19:dd:d9:dd:c25:c25a:d00a:7647
732c19:dd:d9:dd:c25:c25a:d00a:7648/1282c19:dd:d9:dd:c25:c25a:d00a:7648
742c19:dd:d9:dd:c25:c25a:d00a:7649/1282c19:dd:d9:dd:c25:c25a:d00a:7649
752c19:dd:d9:dd:c25:c25a:d00a:764a/1282c19:dd:d9:dd:c25:c25a:d00a:764a
762c19:dd:d9:dd:c25:c25a:d00a:764b/1282c19:dd:d9:dd:c25:c25a:d00a:764b
772c19:dd:d9:dd:c25:c25a:d00a:764c/1282c19:dd:d9:dd:c25:c25a:d00a:764c
782c19:dd:d9:dd:c25:c25a:d00a:764d/1282c19:dd:d9:dd:c25:c25a:d00a:764d
792c19:dd:d9:dd:c25:c25a:d00a:764e/1282c19:dd:d9:dd:c25:c25a:d00a:764e
802c19:dd:d9:dd:c25:c25a:d00a:764f/1282c19:dd:d9:dd:c25:c25a:d00a:764f
812c19:dd:d9:dd:c25:c25a:d00a:7650/1282c19:dd:d9:dd:c25:c25a:d00a:7650
822c19:dd:d9:dd:c25:c25a:d00a:7651/1282c19:dd:d9:dd:c25:c25a:d00a:7651
832c19:dd:d9:dd:c25:c25a:d00a:7652/1282c19:dd:d9:dd:c25:c25a:d00a:7652
842c19:dd:d9:dd:c25:c25a:d00a:7653/1282c19:dd:d9:dd:c25:c25a:d00a:7653
852c19:dd:d9:dd:c25:c25a:d00a:7654/1282c19:dd:d9:dd:c25:c25a:d00a:7654
862c19:dd:d9:dd:c25:c25a:d00a:7655/1282c19:dd:d9:dd:c25:c25a:d00a:7655
872c19:dd:d9:dd:c25:c25a:d00a:7656/1282c19:dd:d9:dd:c25:c25a:d00a:7656
882c19:dd:d9:dd:c25:c25a:d00a:7657/1282c19:dd:d9:dd:c25:c25a:d00a:7657
892c19:dd:d9:dd:c25:c25a:d00a:7658/1282c19:dd:d9:dd:c25:c25a:d00a:7658
902c19:dd:d9:dd:c25:c25a:d00a:7659/1282c19:dd:d9:dd:c25:c25a:d00a:7659
912c19:dd:d9:dd:c25:c25a:d00a:765a/1282c19:dd:d9:dd:c25:c25a:d00a:765a
922c19:dd:d9:dd:c25:c25a:d00a:765b/1282c19:dd:d9:dd:c25:c25a:d00a:765b
932c19:dd:d9:dd:c25:c25a:d00a:765c/1282c19:dd:d9:dd:c25:c25a:d00a:765c
942c19:dd:d9:dd:c25:c25a:d00a:765d/1282c19:dd:d9:dd:c25:c25a:d00a:765d
952c19:dd:d9:dd:c25:c25a:d00a:765e/1282c19:dd:d9:dd:c25:c25a:d00a:765e
962c19:dd:d9:dd:c25:c25a:d00a:765f/1282c19:dd:d9:dd:c25:c25a:d00a:765f
972c19:dd:d9:dd:c25:c25a:d00a:7660/1282c19:dd:d9:dd:c25:c25a:d00a:7660
982c19:dd:d9:dd:c25:c25a:d00a:7661/1282c19:dd:d9:dd:c25:c25a:d00a:7661
992c19:dd:d9:dd:c25:c25a:d00a:7662/1282c19:dd:d9:dd:c25:c25a:d00a:7662
1002c19:dd:d9:dd:c25:c25a:d00a:7663/1282c19:dd:d9:dd:c25:c25a:d00a:7663
1012c19:dd:d9:dd:c25:c25a:d00a:7664/1282c19:dd:d9:dd:c25:c25a:d00a:7664
1022c19:dd:d9:dd:c25:c25a:d00a:7665/1282c19:dd:d9:dd:c25:c25a:d00a:7665
1032c19:dd:d9:dd:c25:c25a:d00a:7666/1282c19:dd:d9:dd:c25:c25a:d00a:7666
1042c19:dd:d9:dd:c25:c25a:d00a:7667/1282c19:dd:d9:dd:c25:c25a:d00a:7667
1052c19:dd:d9:dd:c25:c25a:d00a:7668/1282c19:dd:d9:dd:c25:c25a:d00a:7668
1062c19:dd:d9:dd:c25:c25a:d00a:7669/1282c19:dd:d9:dd:c25:c25a:d00a:7669
1072c19:dd:d9:dd:c25:c25a:d00a:766a/1282c19:dd:d9:dd:c25:c25a:d00a:766a
1082c19:dd:d9:dd:c25:c25a:d00a:766b/1282c19:dd:d9:dd:c25:c25a:d00a:766b
1092c19:dd:d9:dd:c25:c25a:d00a:766c/1282c19:dd:d9:dd:c25:c25a:d00a:766c
1102c19:dd:d9:dd:c25:c25a:d00a:766d/1282c19:dd:d9:dd:c25:c25a:d00a:766d
1112c19:dd:d9:dd:c25:c25a:d00a:766e/1282c19:dd:d9:dd:c25:c25a:d00a:766e
1122c19:dd:d9:dd:c25:c25a:d00a:766f/1282c19:dd:d9:dd:c25:c25a:d00a:766f
1132c19:dd:d9:dd:c25:c25a:d00a:7670/1282c19:dd:d9:dd:c25:c25a:d00a:7670
1142c19:dd:d9:dd:c25:c25a:d00a:7671/1282c19:dd:d9:dd:c25:c25a:d00a:7671
1152c19:dd:d9:dd:c25:c25a:d00a:7672/1282c19:dd:d9:dd:c25:c25a:d00a:7672
1162c19:dd:d9:dd:c25:c25a:d00a:7673/1282c19:dd:d9:dd:c25:c25a:d00a:7673
1172c19:dd:d9:dd:c25:c25a:d00a:7674/1282c19:dd:d9:dd:c25:c25a:d00a:7674
1182c19:dd:d9:dd:c25:c25a:d00a:7675/1282c19:dd:d9:dd:c25:c25a:d00a:7675
1192c19:dd:d9:dd:c25:c25a:d00a:7676/1282c19:dd:d9:dd:c25:c25a:d00a:7676
1202c19:dd:d9:dd:c25:c25a:d00a:7677/1282c19:dd:d9:dd:c25:c25a:d00a:7677
1212c19:dd:d9:dd:c25:c25a:d00a:7678/1282c19:dd:d9:dd:c25:c25a:d00a:7678
1222c19:dd:d9:dd:c25:c25a:d00a:7679/1282c19:dd:d9:dd:c25:c25a:d00a:7679
1232c19:dd:d9:dd:c25:c25a:d00a:767a/1282c19:dd:d9:dd:c25:c25a:d00a:767a
1242c19:dd:d9:dd:c25:c25a:d00a:767b/1282c19:dd:d9:dd:c25:c25a:d00a:767b
1252c19:dd:d9:dd:c25:c25a:d00a:767c/1282c19:dd:d9:dd:c25:c25a:d00a:767c
1262c19:dd:d9:dd:c25:c25a:d00a:767d/1282c19:dd:d9:dd:c25:c25a:d00a:767d
1272c19:dd:d9:dd:c25:c25a:d00a:767e/1282c19:dd:d9:dd:c25:c25a:d00a:767e
1282c19:dd:d9:dd:c25:c25a:d00a:767f/1282c19:dd:d9:dd:c25:c25a:d00a:767f
1292c19:dd:d9:dd:c25:c25a:d00a:7680/1282c19:dd:d9:dd:c25:c25a:d00a:7680
1302c19:dd:d9:dd:c25:c25a:d00a:7681/1282c19:dd:d9:dd:c25:c25a:d00a:7681
1312c19:dd:d9:dd:c25:c25a:d00a:7682/1282c19:dd:d9:dd:c25:c25a:d00a:7682
1322c19:dd:d9:dd:c25:c25a:d00a:7683/1282c19:dd:d9:dd:c25:c25a:d00a:7683
1332c19:dd:d9:dd:c25:c25a:d00a:7684/1282c19:dd:d9:dd:c25:c25a:d00a:7684
1342c19:dd:d9:dd:c25:c25a:d00a:7685/1282c19:dd:d9:dd:c25:c25a:d00a:7685
1352c19:dd:d9:dd:c25:c25a:d00a:7686/1282c19:dd:d9:dd:c25:c25a:d00a:7686
1362c19:dd:d9:dd:c25:c25a:d00a:7687/1282c19:dd:d9:dd:c25:c25a:d00a:7687
1372c19:dd:d9:dd:c25:c25a:d00a:7688/1282c19:dd:d9:dd:c25:c25a:d00a:7688
1382c19:dd:d9:dd:c25:c25a:d00a:7689/1282c19:dd:d9:dd:c25:c25a:d00a:7689
1392c19:dd:d9:dd:c25:c25a:d00a:768a/1282c19:dd:d9:dd:c25:c25a:d00a:768a
1402c19:dd:d9:dd:c25:c25a:d00a:768b/1282c19:dd:d9:dd:c25:c25a:d00a:768b
1412c19:dd:d9:dd:c25:c25a:d00a:768c/1282c19:dd:d9:dd:c25:c25a:d00a:768c
1422c19:dd:d9:dd:c25:c25a:d00a:768d/1282c19:dd:d9:dd:c25:c25a:d00a:768d
1432c19:dd:d9:dd:c25:c25a:d00a:768e/1282c19:dd:d9:dd:c25:c25a:d00a:768e
1442c19:dd:d9:dd:c25:c25a:d00a:768f/1282c19:dd:d9:dd:c25:c25a:d00a:768f
1452c19:dd:d9:dd:c25:c25a:d00a:7690/1282c19:dd:d9:dd:c25:c25a:d00a:7690
1462c19:dd:d9:dd:c25:c25a:d00a:7691/1282c19:dd:d9:dd:c25:c25a:d00a:7691
1472c19:dd:d9:dd:c25:c25a:d00a:7692/1282c19:dd:d9:dd:c25:c25a:d00a:7692
1482c19:dd:d9:dd:c25:c25a:d00a:7693/1282c19:dd:d9:dd:c25:c25a:d00a:7693
1492c19:dd:d9:dd:c25:c25a:d00a:7694/1282c19:dd:d9:dd:c25:c25a:d00a:7694
1502c19:dd:d9:dd:c25:c25a:d00a:7695/1282c19:dd:d9:dd:c25:c25a:d00a:7695
1512c19:dd:d9:dd:c25:c25a:d00a:7696/1282c19:dd:d9:dd:c25:c25a:d00a:7696
1522c19:dd:d9:dd:c25:c25a:d00a:7697/1282c19:dd:d9:dd:c25:c25a:d00a:7697
1532c19:dd:d9:dd:c25:c25a:d00a:7698/1282c19:dd:d9:dd:c25:c25a:d00a:7698
1542c19:dd:d9:dd:c25:c25a:d00a:7699/1282c19:dd:d9:dd:c25:c25a:d00a:7699
1552c19:dd:d9:dd:c25:c25a:d00a:769a/1282c19:dd:d9:dd:c25:c25a:d00a:769a
1562c19:dd:d9:dd:c25:c25a:d00a:769b/1282c19:dd:d9:dd:c25:c25a:d00a:769b
1572c19:dd:d9:dd:c25:c25a:d00a:769c/1282c19:dd:d9:dd:c25:c25a:d00a:769c
1582c19:dd:d9:dd:c25:c25a:d00a:769d/1282c19:dd:d9:dd:c25:c25a:d00a:769d
1592c19:dd:d9:dd:c25:c25a:d00a:769e/1282c19:dd:d9:dd:c25:c25a:d00a:769e
1602c19:dd:d9:dd:c25:c25a:d00a:769f/1282c19:dd:d9:dd:c25:c25a:d00a:769f
1612c19:dd:d9:dd:c25:c25a:d00a:76a0/1282c19:dd:d9:dd:c25:c25a:d00a:76a0
1622c19:dd:d9:dd:c25:c25a:d00a:76a1/1282c19:dd:d9:dd:c25:c25a:d00a:76a1
1632c19:dd:d9:dd:c25:c25a:d00a:76a2/1282c19:dd:d9:dd:c25:c25a:d00a:76a2
1642c19:dd:d9:dd:c25:c25a:d00a:76a3/1282c19:dd:d9:dd:c25:c25a:d00a:76a3
1652c19:dd:d9:dd:c25:c25a:d00a:76a4/1282c19:dd:d9:dd:c25:c25a:d00a:76a4
1662c19:dd:d9:dd:c25:c25a:d00a:76a5/1282c19:dd:d9:dd:c25:c25a:d00a:76a5
1672c19:dd:d9:dd:c25:c25a:d00a:76a6/1282c19:dd:d9:dd:c25:c25a:d00a:76a6
1682c19:dd:d9:dd:c25:c25a:d00a:76a7/1282c19:dd:d9:dd:c25:c25a:d00a:76a7
1692c19:dd:d9:dd:c25:c25a:d00a:76a8/1282c19:dd:d9:dd:c25:c25a:d00a:76a8
1702c19:dd:d9:dd:c25:c25a:d00a:76a9/1282c19:dd:d9:dd:c25:c25a:d00a:76a9
1712c19:dd:d9:dd:c25:c25a:d00a:76aa/1282c19:dd:d9:dd:c25:c25a:d00a:76aa
1722c19:dd:d9:dd:c25:c25a:d00a:76ab/1282c19:dd:d9:dd:c25:c25a:d00a:76ab
1732c19:dd:d9:dd:c25:c25a:d00a:76ac/1282c19:dd:d9:dd:c25:c25a:d00a:76ac
1742c19:dd:d9:dd:c25:c25a:d00a:76ad/1282c19:dd:d9:dd:c25:c25a:d00a:76ad
1752c19:dd:d9:dd:c25:c25a:d00a:76ae/1282c19:dd:d9:dd:c25:c25a:d00a:76ae
1762c19:dd:d9:dd:c25:c25a:d00a:76af/1282c19:dd:d9:dd:c25:c25a:d00a:76af
1772c19:dd:d9:dd:c25:c25a:d00a:76b0/1282c19:dd:d9:dd:c25:c25a:d00a:76b0
1782c19:dd:d9:dd:c25:c25a:d00a:76b1/1282c19:dd:d9:dd:c25:c25a:d00a:76b1
1792c19:dd:d9:dd:c25:c25a:d00a:76b2/1282c19:dd:d9:dd:c25:c25a:d00a:76b2
1802c19:dd:d9:dd:c25:c25a:d00a:76b3/1282c19:dd:d9:dd:c25:c25a:d00a:76b3
1812c19:dd:d9:dd:c25:c25a:d00a:76b4/1282c19:dd:d9:dd:c25:c25a:d00a:76b4
1822c19:dd:d9:dd:c25:c25a:d00a:76b5/1282c19:dd:d9:dd:c25:c25a:d00a:76b5
1832c19:dd:d9:dd:c25:c25a:d00a:76b6/1282c19:dd:d9:dd:c25:c25a:d00a:76b6
1842c19:dd:d9:dd:c25:c25a:d00a:76b7/1282c19:dd:d9:dd:c25:c25a:d00a:76b7
1852c19:dd:d9:dd:c25:c25a:d00a:76b8/1282c19:dd:d9:dd:c25:c25a:d00a:76b8
1862c19:dd:d9:dd:c25:c25a:d00a:76b9/1282c19:dd:d9:dd:c25:c25a:d00a:76b9
1872c19:dd:d9:dd:c25:c25a:d00a:76ba/1282c19:dd:d9:dd:c25:c25a:d00a:76ba
1882c19:dd:d9:dd:c25:c25a:d00a:76bb/1282c19:dd:d9:dd:c25:c25a:d00a:76bb
1892c19:dd:d9:dd:c25:c25a:d00a:76bc/1282c19:dd:d9:dd:c25:c25a:d00a:76bc
1902c19:dd:d9:dd:c25:c25a:d00a:76bd/1282c19:dd:d9:dd:c25:c25a:d00a:76bd
1912c19:dd:d9:dd:c25:c25a:d00a:76be/1282c19:dd:d9:dd:c25:c25a:d00a:76be
1922c19:dd:d9:dd:c25:c25a:d00a:76bf/1282c19:dd:d9:dd:c25:c25a:d00a:76bf
1932c19:dd:d9:dd:c25:c25a:d00a:76c0/1282c19:dd:d9:dd:c25:c25a:d00a:76c0
1942c19:dd:d9:dd:c25:c25a:d00a:76c1/1282c19:dd:d9:dd:c25:c25a:d00a:76c1
1952c19:dd:d9:dd:c25:c25a:d00a:76c2/1282c19:dd:d9:dd:c25:c25a:d00a:76c2
1962c19:dd:d9:dd:c25:c25a:d00a:76c3/1282c19:dd:d9:dd:c25:c25a:d00a:76c3
1972c19:dd:d9:dd:c25:c25a:d00a:76c4/1282c19:dd:d9:dd:c25:c25a:d00a:76c4
1982c19:dd:d9:dd:c25:c25a:d00a:76c5/1282c19:dd:d9:dd:c25:c25a:d00a:76c5
1992c19:dd:d9:dd:c25:c25a:d00a:76c6/1282c19:dd:d9:dd:c25:c25a:d00a:76c6
2002c19:dd:d9:dd:c25:c25a:d00a:76c7/1282c19:dd:d9:dd:c25:c25a:d00a:76c7
2012c19:dd:d9:dd:c25:c25a:d00a:76c8/1282c19:dd:d9:dd:c25:c25a:d00a:76c8
2022c19:dd:d9:dd:c25:c25a:d00a:76c9/1282c19:dd:d9:dd:c25:c25a:d00a:76c9
2032c19:dd:d9:dd:c25:c25a:d00a:76ca/1282c19:dd:d9:dd:c25:c25a:d00a:76ca
2042c19:dd:d9:dd:c25:c25a:d00a:76cb/1282c19:dd:d9:dd:c25:c25a:d00a:76cb
2052c19:dd:d9:dd:c25:c25a:d00a:76cc/1282c19:dd:d9:dd:c25:c25a:d00a:76cc
2062c19:dd:d9:dd:c25:c25a:d00a:76cd/1282c19:dd:d9:dd:c25:c25a:d00a:76cd
2072c19:dd:d9:dd:c25:c25a:d00a:76ce/1282c19:dd:d9:dd:c25:c25a:d00a:76ce
2082c19:dd:d9:dd:c25:c25a:d00a:76cf/1282c19:dd:d9:dd:c25:c25a:d00a:76cf
2092c19:dd:d9:dd:c25:c25a:d00a:76d0/1282c19:dd:d9:dd:c25:c25a:d00a:76d0
2102c19:dd:d9:dd:c25:c25a:d00a:76d1/1282c19:dd:d9:dd:c25:c25a:d00a:76d1
2112c19:dd:d9:dd:c25:c25a:d00a:76d2/1282c19:dd:d9:dd:c25:c25a:d00a:76d2
2122c19:dd:d9:dd:c25:c25a:d00a:76d3/1282c19:dd:d9:dd:c25:c25a:d00a:76d3
2132c19:dd:d9:dd:c25:c25a:d00a:76d4/1282c19:dd:d9:dd:c25:c25a:d00a:76d4
2142c19:dd:d9:dd:c25:c25a:d00a:76d5/1282c19:dd:d9:dd:c25:c25a:d00a:76d5
2152c19:dd:d9:dd:c25:c25a:d00a:76d6/1282c19:dd:d9:dd:c25:c25a:d00a:76d6
2162c19:dd:d9:dd:c25:c25a:d00a:76d7/1282c19:dd:d9:dd:c25:c25a:d00a:76d7
2172c19:dd:d9:dd:c25:c25a:d00a:76d8/1282c19:dd:d9:dd:c25:c25a:d00a:76d8
2182c19:dd:d9:dd:c25:c25a:d00a:76d9/1282c19:dd:d9:dd:c25:c25a:d00a:76d9
2192c19:dd:d9:dd:c25:c25a:d00a:76da/1282c19:dd:d9:dd:c25:c25a:d00a:76da
2202c19:dd:d9:dd:c25:c25a:d00a:76db/1282c19:dd:d9:dd:c25:c25a:d00a:76db
2212c19:dd:d9:dd:c25:c25a:d00a:76dc/1282c19:dd:d9:dd:c25:c25a:d00a:76dc
2222c19:dd:d9:dd:c25:c25a:d00a:76dd/1282c19:dd:d9:dd:c25:c25a:d00a:76dd
2232c19:dd:d9:dd:c25:c25a:d00a:76de/1282c19:dd:d9:dd:c25:c25a:d00a:76de
2242c19:dd:d9:dd:c25:c25a:d00a:76df/1282c19:dd:d9:dd:c25:c25a:d00a:76df
2252c19:dd:d9:dd:c25:c25a:d00a:76e0/1282c19:dd:d9:dd:c25:c25a:d00a:76e0
2262c19:dd:d9:dd:c25:c25a:d00a:76e1/1282c19:dd:d9:dd:c25:c25a:d00a:76e1
2272c19:dd:d9:dd:c25:c25a:d00a:76e2/1282c19:dd:d9:dd:c25:c25a:d00a:76e2
2282c19:dd:d9:dd:c25:c25a:d00a:76e3/1282c19:dd:d9:dd:c25:c25a:d00a:76e3
2292c19:dd:d9:dd:c25:c25a:d00a:76e4/1282c19:dd:d9:dd:c25:c25a:d00a:76e4
2302c19:dd:d9:dd:c25:c25a:d00a:76e5/1282c19:dd:d9:dd:c25:c25a:d00a:76e5
2312c19:dd:d9:dd:c25:c25a:d00a:76e6/1282c19:dd:d9:dd:c25:c25a:d00a:76e6
2322c19:dd:d9:dd:c25:c25a:d00a:76e7/1282c19:dd:d9:dd:c25:c25a:d00a:76e7
2332c19:dd:d9:dd:c25:c25a:d00a:76e8/1282c19:dd:d9:dd:c25:c25a:d00a:76e8
2342c19:dd:d9:dd:c25:c25a:d00a:76e9/1282c19:dd:d9:dd:c25:c25a:d00a:76e9
2352c19:dd:d9:dd:c25:c25a:d00a:76ea/1282c19:dd:d9:dd:c25:c25a:d00a:76ea
2362c19:dd:d9:dd:c25:c25a:d00a:76eb/1282c19:dd:d9:dd:c25:c25a:d00a:76eb
2372c19:dd:d9:dd:c25:c25a:d00a:76ec/1282c19:dd:d9:dd:c25:c25a:d00a:76ec
2382c19:dd:d9:dd:c25:c25a:d00a:76ed/1282c19:dd:d9:dd:c25:c25a:d00a:76ed
2392c19:dd:d9:dd:c25:c25a:d00a:76ee/1282c19:dd:d9:dd:c25:c25a:d00a:76ee
2402c19:dd:d9:dd:c25:c25a:d00a:76ef/1282c19:dd:d9:dd:c25:c25a:d00a:76ef
2412c19:dd:d9:dd:c25:c25a:d00a:76f0/1282c19:dd:d9:dd:c25:c25a:d00a:76f0
2422c19:dd:d9:dd:c25:c25a:d00a:76f1/1282c19:dd:d9:dd:c25:c25a:d00a:76f1
2432c19:dd:d9:dd:c25:c25a:d00a:76f2/1282c19:dd:d9:dd:c25:c25a:d00a:76f2
2442c19:dd:d9:dd:c25:c25a:d00a:76f3/1282c19:dd:d9:dd:c25:c25a:d00a:76f3
2452c19:dd:d9:dd:c25:c25a:d00a:76f4/1282c19:dd:d9:dd:c25:c25a:d00a:76f4
2462c19:dd:d9:dd:c25:c25a:d00a:76f5/1282c19:dd:d9:dd:c25:c25a:d00a:76f5
2472c19:dd:d9:dd:c25:c25a:d00a:76f6/1282c19:dd:d9:dd:c25:c25a:d00a:76f6
2482c19:dd:d9:dd:c25:c25a:d00a:76f7/1282c19:dd:d9:dd:c25:c25a:d00a:76f7
2492c19:dd:d9:dd:c25:c25a:d00a:76f8/1282c19:dd:d9:dd:c25:c25a:d00a:76f8
2502c19:dd:d9:dd:c25:c25a:d00a:76f9/1282c19:dd:d9:dd:c25:c25a:d00a:76f9
2512c19:dd:d9:dd:c25:c25a:d00a:76fa/1282c19:dd:d9:dd:c25:c25a:d00a:76fa
2522c19:dd:d9:dd:c25:c25a:d00a:76fb/1282c19:dd:d9:dd:c25:c25a:d00a:76fb
2532c19:dd:d9:dd:c25:c25a:d00a:76fc/1282c19:dd:d9:dd:c25:c25a:d00a:76fc
2542c19:dd:d9:dd:c25:c25a:d00a:76fd/1282c19:dd:d9:dd:c25:c25a:d00a:76fd
2552c19:dd:d9:dd:c25:c25a:d00a:76fe/1282c19:dd:d9:dd:c25:c25a:d00a:76fe
2562c19:dd:d9:dd:c25:c25a:d00a:76ff/1282c19:dd:d9:dd:c25:c25a:d00a:76ff

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.