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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:c25:dd00:d500/120
First address
2c19:dd:d9:dd:c25:c25:dd00:d500
Last address
2c19:dd:d9:dd:c25:c25:dd00:d5ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:dd00:d500
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.d.0.0.d.d.5.2.c.0.5.2.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:c25:dd00:d500/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:dd00:d500/1282c19:dd:d9:dd:c25:c25:dd00:d500
22c19:dd:d9:dd:c25:c25:dd00:d501/1282c19:dd:d9:dd:c25:c25:dd00:d501
32c19:dd:d9:dd:c25:c25:dd00:d502/1282c19:dd:d9:dd:c25:c25:dd00:d502
42c19:dd:d9:dd:c25:c25:dd00:d503/1282c19:dd:d9:dd:c25:c25:dd00:d503
52c19:dd:d9:dd:c25:c25:dd00:d504/1282c19:dd:d9:dd:c25:c25:dd00:d504
62c19:dd:d9:dd:c25:c25:dd00:d505/1282c19:dd:d9:dd:c25:c25:dd00:d505
72c19:dd:d9:dd:c25:c25:dd00:d506/1282c19:dd:d9:dd:c25:c25:dd00:d506
82c19:dd:d9:dd:c25:c25:dd00:d507/1282c19:dd:d9:dd:c25:c25:dd00:d507
92c19:dd:d9:dd:c25:c25:dd00:d508/1282c19:dd:d9:dd:c25:c25:dd00:d508
102c19:dd:d9:dd:c25:c25:dd00:d509/1282c19:dd:d9:dd:c25:c25:dd00:d509
112c19:dd:d9:dd:c25:c25:dd00:d50a/1282c19:dd:d9:dd:c25:c25:dd00:d50a
122c19:dd:d9:dd:c25:c25:dd00:d50b/1282c19:dd:d9:dd:c25:c25:dd00:d50b
132c19:dd:d9:dd:c25:c25:dd00:d50c/1282c19:dd:d9:dd:c25:c25:dd00:d50c
142c19:dd:d9:dd:c25:c25:dd00:d50d/1282c19:dd:d9:dd:c25:c25:dd00:d50d
152c19:dd:d9:dd:c25:c25:dd00:d50e/1282c19:dd:d9:dd:c25:c25:dd00:d50e
162c19:dd:d9:dd:c25:c25:dd00:d50f/1282c19:dd:d9:dd:c25:c25:dd00:d50f
172c19:dd:d9:dd:c25:c25:dd00:d510/1282c19:dd:d9:dd:c25:c25:dd00:d510
182c19:dd:d9:dd:c25:c25:dd00:d511/1282c19:dd:d9:dd:c25:c25:dd00:d511
192c19:dd:d9:dd:c25:c25:dd00:d512/1282c19:dd:d9:dd:c25:c25:dd00:d512
202c19:dd:d9:dd:c25:c25:dd00:d513/1282c19:dd:d9:dd:c25:c25:dd00:d513
212c19:dd:d9:dd:c25:c25:dd00:d514/1282c19:dd:d9:dd:c25:c25:dd00:d514
222c19:dd:d9:dd:c25:c25:dd00:d515/1282c19:dd:d9:dd:c25:c25:dd00:d515
232c19:dd:d9:dd:c25:c25:dd00:d516/1282c19:dd:d9:dd:c25:c25:dd00:d516
242c19:dd:d9:dd:c25:c25:dd00:d517/1282c19:dd:d9:dd:c25:c25:dd00:d517
252c19:dd:d9:dd:c25:c25:dd00:d518/1282c19:dd:d9:dd:c25:c25:dd00:d518
262c19:dd:d9:dd:c25:c25:dd00:d519/1282c19:dd:d9:dd:c25:c25:dd00:d519
272c19:dd:d9:dd:c25:c25:dd00:d51a/1282c19:dd:d9:dd:c25:c25:dd00:d51a
282c19:dd:d9:dd:c25:c25:dd00:d51b/1282c19:dd:d9:dd:c25:c25:dd00:d51b
292c19:dd:d9:dd:c25:c25:dd00:d51c/1282c19:dd:d9:dd:c25:c25:dd00:d51c
302c19:dd:d9:dd:c25:c25:dd00:d51d/1282c19:dd:d9:dd:c25:c25:dd00:d51d
312c19:dd:d9:dd:c25:c25:dd00:d51e/1282c19:dd:d9:dd:c25:c25:dd00:d51e
322c19:dd:d9:dd:c25:c25:dd00:d51f/1282c19:dd:d9:dd:c25:c25:dd00:d51f
332c19:dd:d9:dd:c25:c25:dd00:d520/1282c19:dd:d9:dd:c25:c25:dd00:d520
342c19:dd:d9:dd:c25:c25:dd00:d521/1282c19:dd:d9:dd:c25:c25:dd00:d521
352c19:dd:d9:dd:c25:c25:dd00:d522/1282c19:dd:d9:dd:c25:c25:dd00:d522
362c19:dd:d9:dd:c25:c25:dd00:d523/1282c19:dd:d9:dd:c25:c25:dd00:d523
372c19:dd:d9:dd:c25:c25:dd00:d524/1282c19:dd:d9:dd:c25:c25:dd00:d524
382c19:dd:d9:dd:c25:c25:dd00:d525/1282c19:dd:d9:dd:c25:c25:dd00:d525
392c19:dd:d9:dd:c25:c25:dd00:d526/1282c19:dd:d9:dd:c25:c25:dd00:d526
402c19:dd:d9:dd:c25:c25:dd00:d527/1282c19:dd:d9:dd:c25:c25:dd00:d527
412c19:dd:d9:dd:c25:c25:dd00:d528/1282c19:dd:d9:dd:c25:c25:dd00:d528
422c19:dd:d9:dd:c25:c25:dd00:d529/1282c19:dd:d9:dd:c25:c25:dd00:d529
432c19:dd:d9:dd:c25:c25:dd00:d52a/1282c19:dd:d9:dd:c25:c25:dd00:d52a
442c19:dd:d9:dd:c25:c25:dd00:d52b/1282c19:dd:d9:dd:c25:c25:dd00:d52b
452c19:dd:d9:dd:c25:c25:dd00:d52c/1282c19:dd:d9:dd:c25:c25:dd00:d52c
462c19:dd:d9:dd:c25:c25:dd00:d52d/1282c19:dd:d9:dd:c25:c25:dd00:d52d
472c19:dd:d9:dd:c25:c25:dd00:d52e/1282c19:dd:d9:dd:c25:c25:dd00:d52e
482c19:dd:d9:dd:c25:c25:dd00:d52f/1282c19:dd:d9:dd:c25:c25:dd00:d52f
492c19:dd:d9:dd:c25:c25:dd00:d530/1282c19:dd:d9:dd:c25:c25:dd00:d530
502c19:dd:d9:dd:c25:c25:dd00:d531/1282c19:dd:d9:dd:c25:c25:dd00:d531
512c19:dd:d9:dd:c25:c25:dd00:d532/1282c19:dd:d9:dd:c25:c25:dd00:d532
522c19:dd:d9:dd:c25:c25:dd00:d533/1282c19:dd:d9:dd:c25:c25:dd00:d533
532c19:dd:d9:dd:c25:c25:dd00:d534/1282c19:dd:d9:dd:c25:c25:dd00:d534
542c19:dd:d9:dd:c25:c25:dd00:d535/1282c19:dd:d9:dd:c25:c25:dd00:d535
552c19:dd:d9:dd:c25:c25:dd00:d536/1282c19:dd:d9:dd:c25:c25:dd00:d536
562c19:dd:d9:dd:c25:c25:dd00:d537/1282c19:dd:d9:dd:c25:c25:dd00:d537
572c19:dd:d9:dd:c25:c25:dd00:d538/1282c19:dd:d9:dd:c25:c25:dd00:d538
582c19:dd:d9:dd:c25:c25:dd00:d539/1282c19:dd:d9:dd:c25:c25:dd00:d539
592c19:dd:d9:dd:c25:c25:dd00:d53a/1282c19:dd:d9:dd:c25:c25:dd00:d53a
602c19:dd:d9:dd:c25:c25:dd00:d53b/1282c19:dd:d9:dd:c25:c25:dd00:d53b
612c19:dd:d9:dd:c25:c25:dd00:d53c/1282c19:dd:d9:dd:c25:c25:dd00:d53c
622c19:dd:d9:dd:c25:c25:dd00:d53d/1282c19:dd:d9:dd:c25:c25:dd00:d53d
632c19:dd:d9:dd:c25:c25:dd00:d53e/1282c19:dd:d9:dd:c25:c25:dd00:d53e
642c19:dd:d9:dd:c25:c25:dd00:d53f/1282c19:dd:d9:dd:c25:c25:dd00:d53f
652c19:dd:d9:dd:c25:c25:dd00:d540/1282c19:dd:d9:dd:c25:c25:dd00:d540
662c19:dd:d9:dd:c25:c25:dd00:d541/1282c19:dd:d9:dd:c25:c25:dd00:d541
672c19:dd:d9:dd:c25:c25:dd00:d542/1282c19:dd:d9:dd:c25:c25:dd00:d542
682c19:dd:d9:dd:c25:c25:dd00:d543/1282c19:dd:d9:dd:c25:c25:dd00:d543
692c19:dd:d9:dd:c25:c25:dd00:d544/1282c19:dd:d9:dd:c25:c25:dd00:d544
702c19:dd:d9:dd:c25:c25:dd00:d545/1282c19:dd:d9:dd:c25:c25:dd00:d545
712c19:dd:d9:dd:c25:c25:dd00:d546/1282c19:dd:d9:dd:c25:c25:dd00:d546
722c19:dd:d9:dd:c25:c25:dd00:d547/1282c19:dd:d9:dd:c25:c25:dd00:d547
732c19:dd:d9:dd:c25:c25:dd00:d548/1282c19:dd:d9:dd:c25:c25:dd00:d548
742c19:dd:d9:dd:c25:c25:dd00:d549/1282c19:dd:d9:dd:c25:c25:dd00:d549
752c19:dd:d9:dd:c25:c25:dd00:d54a/1282c19:dd:d9:dd:c25:c25:dd00:d54a
762c19:dd:d9:dd:c25:c25:dd00:d54b/1282c19:dd:d9:dd:c25:c25:dd00:d54b
772c19:dd:d9:dd:c25:c25:dd00:d54c/1282c19:dd:d9:dd:c25:c25:dd00:d54c
782c19:dd:d9:dd:c25:c25:dd00:d54d/1282c19:dd:d9:dd:c25:c25:dd00:d54d
792c19:dd:d9:dd:c25:c25:dd00:d54e/1282c19:dd:d9:dd:c25:c25:dd00:d54e
802c19:dd:d9:dd:c25:c25:dd00:d54f/1282c19:dd:d9:dd:c25:c25:dd00:d54f
812c19:dd:d9:dd:c25:c25:dd00:d550/1282c19:dd:d9:dd:c25:c25:dd00:d550
822c19:dd:d9:dd:c25:c25:dd00:d551/1282c19:dd:d9:dd:c25:c25:dd00:d551
832c19:dd:d9:dd:c25:c25:dd00:d552/1282c19:dd:d9:dd:c25:c25:dd00:d552
842c19:dd:d9:dd:c25:c25:dd00:d553/1282c19:dd:d9:dd:c25:c25:dd00:d553
852c19:dd:d9:dd:c25:c25:dd00:d554/1282c19:dd:d9:dd:c25:c25:dd00:d554
862c19:dd:d9:dd:c25:c25:dd00:d555/1282c19:dd:d9:dd:c25:c25:dd00:d555
872c19:dd:d9:dd:c25:c25:dd00:d556/1282c19:dd:d9:dd:c25:c25:dd00:d556
882c19:dd:d9:dd:c25:c25:dd00:d557/1282c19:dd:d9:dd:c25:c25:dd00:d557
892c19:dd:d9:dd:c25:c25:dd00:d558/1282c19:dd:d9:dd:c25:c25:dd00:d558
902c19:dd:d9:dd:c25:c25:dd00:d559/1282c19:dd:d9:dd:c25:c25:dd00:d559
912c19:dd:d9:dd:c25:c25:dd00:d55a/1282c19:dd:d9:dd:c25:c25:dd00:d55a
922c19:dd:d9:dd:c25:c25:dd00:d55b/1282c19:dd:d9:dd:c25:c25:dd00:d55b
932c19:dd:d9:dd:c25:c25:dd00:d55c/1282c19:dd:d9:dd:c25:c25:dd00:d55c
942c19:dd:d9:dd:c25:c25:dd00:d55d/1282c19:dd:d9:dd:c25:c25:dd00:d55d
952c19:dd:d9:dd:c25:c25:dd00:d55e/1282c19:dd:d9:dd:c25:c25:dd00:d55e
962c19:dd:d9:dd:c25:c25:dd00:d55f/1282c19:dd:d9:dd:c25:c25:dd00:d55f
972c19:dd:d9:dd:c25:c25:dd00:d560/1282c19:dd:d9:dd:c25:c25:dd00:d560
982c19:dd:d9:dd:c25:c25:dd00:d561/1282c19:dd:d9:dd:c25:c25:dd00:d561
992c19:dd:d9:dd:c25:c25:dd00:d562/1282c19:dd:d9:dd:c25:c25:dd00:d562
1002c19:dd:d9:dd:c25:c25:dd00:d563/1282c19:dd:d9:dd:c25:c25:dd00:d563
1012c19:dd:d9:dd:c25:c25:dd00:d564/1282c19:dd:d9:dd:c25:c25:dd00:d564
1022c19:dd:d9:dd:c25:c25:dd00:d565/1282c19:dd:d9:dd:c25:c25:dd00:d565
1032c19:dd:d9:dd:c25:c25:dd00:d566/1282c19:dd:d9:dd:c25:c25:dd00:d566
1042c19:dd:d9:dd:c25:c25:dd00:d567/1282c19:dd:d9:dd:c25:c25:dd00:d567
1052c19:dd:d9:dd:c25:c25:dd00:d568/1282c19:dd:d9:dd:c25:c25:dd00:d568
1062c19:dd:d9:dd:c25:c25:dd00:d569/1282c19:dd:d9:dd:c25:c25:dd00:d569
1072c19:dd:d9:dd:c25:c25:dd00:d56a/1282c19:dd:d9:dd:c25:c25:dd00:d56a
1082c19:dd:d9:dd:c25:c25:dd00:d56b/1282c19:dd:d9:dd:c25:c25:dd00:d56b
1092c19:dd:d9:dd:c25:c25:dd00:d56c/1282c19:dd:d9:dd:c25:c25:dd00:d56c
1102c19:dd:d9:dd:c25:c25:dd00:d56d/1282c19:dd:d9:dd:c25:c25:dd00:d56d
1112c19:dd:d9:dd:c25:c25:dd00:d56e/1282c19:dd:d9:dd:c25:c25:dd00:d56e
1122c19:dd:d9:dd:c25:c25:dd00:d56f/1282c19:dd:d9:dd:c25:c25:dd00:d56f
1132c19:dd:d9:dd:c25:c25:dd00:d570/1282c19:dd:d9:dd:c25:c25:dd00:d570
1142c19:dd:d9:dd:c25:c25:dd00:d571/1282c19:dd:d9:dd:c25:c25:dd00:d571
1152c19:dd:d9:dd:c25:c25:dd00:d572/1282c19:dd:d9:dd:c25:c25:dd00:d572
1162c19:dd:d9:dd:c25:c25:dd00:d573/1282c19:dd:d9:dd:c25:c25:dd00:d573
1172c19:dd:d9:dd:c25:c25:dd00:d574/1282c19:dd:d9:dd:c25:c25:dd00:d574
1182c19:dd:d9:dd:c25:c25:dd00:d575/1282c19:dd:d9:dd:c25:c25:dd00:d575
1192c19:dd:d9:dd:c25:c25:dd00:d576/1282c19:dd:d9:dd:c25:c25:dd00:d576
1202c19:dd:d9:dd:c25:c25:dd00:d577/1282c19:dd:d9:dd:c25:c25:dd00:d577
1212c19:dd:d9:dd:c25:c25:dd00:d578/1282c19:dd:d9:dd:c25:c25:dd00:d578
1222c19:dd:d9:dd:c25:c25:dd00:d579/1282c19:dd:d9:dd:c25:c25:dd00:d579
1232c19:dd:d9:dd:c25:c25:dd00:d57a/1282c19:dd:d9:dd:c25:c25:dd00:d57a
1242c19:dd:d9:dd:c25:c25:dd00:d57b/1282c19:dd:d9:dd:c25:c25:dd00:d57b
1252c19:dd:d9:dd:c25:c25:dd00:d57c/1282c19:dd:d9:dd:c25:c25:dd00:d57c
1262c19:dd:d9:dd:c25:c25:dd00:d57d/1282c19:dd:d9:dd:c25:c25:dd00:d57d
1272c19:dd:d9:dd:c25:c25:dd00:d57e/1282c19:dd:d9:dd:c25:c25:dd00:d57e
1282c19:dd:d9:dd:c25:c25:dd00:d57f/1282c19:dd:d9:dd:c25:c25:dd00:d57f
1292c19:dd:d9:dd:c25:c25:dd00:d580/1282c19:dd:d9:dd:c25:c25:dd00:d580
1302c19:dd:d9:dd:c25:c25:dd00:d581/1282c19:dd:d9:dd:c25:c25:dd00:d581
1312c19:dd:d9:dd:c25:c25:dd00:d582/1282c19:dd:d9:dd:c25:c25:dd00:d582
1322c19:dd:d9:dd:c25:c25:dd00:d583/1282c19:dd:d9:dd:c25:c25:dd00:d583
1332c19:dd:d9:dd:c25:c25:dd00:d584/1282c19:dd:d9:dd:c25:c25:dd00:d584
1342c19:dd:d9:dd:c25:c25:dd00:d585/1282c19:dd:d9:dd:c25:c25:dd00:d585
1352c19:dd:d9:dd:c25:c25:dd00:d586/1282c19:dd:d9:dd:c25:c25:dd00:d586
1362c19:dd:d9:dd:c25:c25:dd00:d587/1282c19:dd:d9:dd:c25:c25:dd00:d587
1372c19:dd:d9:dd:c25:c25:dd00:d588/1282c19:dd:d9:dd:c25:c25:dd00:d588
1382c19:dd:d9:dd:c25:c25:dd00:d589/1282c19:dd:d9:dd:c25:c25:dd00:d589
1392c19:dd:d9:dd:c25:c25:dd00:d58a/1282c19:dd:d9:dd:c25:c25:dd00:d58a
1402c19:dd:d9:dd:c25:c25:dd00:d58b/1282c19:dd:d9:dd:c25:c25:dd00:d58b
1412c19:dd:d9:dd:c25:c25:dd00:d58c/1282c19:dd:d9:dd:c25:c25:dd00:d58c
1422c19:dd:d9:dd:c25:c25:dd00:d58d/1282c19:dd:d9:dd:c25:c25:dd00:d58d
1432c19:dd:d9:dd:c25:c25:dd00:d58e/1282c19:dd:d9:dd:c25:c25:dd00:d58e
1442c19:dd:d9:dd:c25:c25:dd00:d58f/1282c19:dd:d9:dd:c25:c25:dd00:d58f
1452c19:dd:d9:dd:c25:c25:dd00:d590/1282c19:dd:d9:dd:c25:c25:dd00:d590
1462c19:dd:d9:dd:c25:c25:dd00:d591/1282c19:dd:d9:dd:c25:c25:dd00:d591
1472c19:dd:d9:dd:c25:c25:dd00:d592/1282c19:dd:d9:dd:c25:c25:dd00:d592
1482c19:dd:d9:dd:c25:c25:dd00:d593/1282c19:dd:d9:dd:c25:c25:dd00:d593
1492c19:dd:d9:dd:c25:c25:dd00:d594/1282c19:dd:d9:dd:c25:c25:dd00:d594
1502c19:dd:d9:dd:c25:c25:dd00:d595/1282c19:dd:d9:dd:c25:c25:dd00:d595
1512c19:dd:d9:dd:c25:c25:dd00:d596/1282c19:dd:d9:dd:c25:c25:dd00:d596
1522c19:dd:d9:dd:c25:c25:dd00:d597/1282c19:dd:d9:dd:c25:c25:dd00:d597
1532c19:dd:d9:dd:c25:c25:dd00:d598/1282c19:dd:d9:dd:c25:c25:dd00:d598
1542c19:dd:d9:dd:c25:c25:dd00:d599/1282c19:dd:d9:dd:c25:c25:dd00:d599
1552c19:dd:d9:dd:c25:c25:dd00:d59a/1282c19:dd:d9:dd:c25:c25:dd00:d59a
1562c19:dd:d9:dd:c25:c25:dd00:d59b/1282c19:dd:d9:dd:c25:c25:dd00:d59b
1572c19:dd:d9:dd:c25:c25:dd00:d59c/1282c19:dd:d9:dd:c25:c25:dd00:d59c
1582c19:dd:d9:dd:c25:c25:dd00:d59d/1282c19:dd:d9:dd:c25:c25:dd00:d59d
1592c19:dd:d9:dd:c25:c25:dd00:d59e/1282c19:dd:d9:dd:c25:c25:dd00:d59e
1602c19:dd:d9:dd:c25:c25:dd00:d59f/1282c19:dd:d9:dd:c25:c25:dd00:d59f
1612c19:dd:d9:dd:c25:c25:dd00:d5a0/1282c19:dd:d9:dd:c25:c25:dd00:d5a0
1622c19:dd:d9:dd:c25:c25:dd00:d5a1/1282c19:dd:d9:dd:c25:c25:dd00:d5a1
1632c19:dd:d9:dd:c25:c25:dd00:d5a2/1282c19:dd:d9:dd:c25:c25:dd00:d5a2
1642c19:dd:d9:dd:c25:c25:dd00:d5a3/1282c19:dd:d9:dd:c25:c25:dd00:d5a3
1652c19:dd:d9:dd:c25:c25:dd00:d5a4/1282c19:dd:d9:dd:c25:c25:dd00:d5a4
1662c19:dd:d9:dd:c25:c25:dd00:d5a5/1282c19:dd:d9:dd:c25:c25:dd00:d5a5
1672c19:dd:d9:dd:c25:c25:dd00:d5a6/1282c19:dd:d9:dd:c25:c25:dd00:d5a6
1682c19:dd:d9:dd:c25:c25:dd00:d5a7/1282c19:dd:d9:dd:c25:c25:dd00:d5a7
1692c19:dd:d9:dd:c25:c25:dd00:d5a8/1282c19:dd:d9:dd:c25:c25:dd00:d5a8
1702c19:dd:d9:dd:c25:c25:dd00:d5a9/1282c19:dd:d9:dd:c25:c25:dd00:d5a9
1712c19:dd:d9:dd:c25:c25:dd00:d5aa/1282c19:dd:d9:dd:c25:c25:dd00:d5aa
1722c19:dd:d9:dd:c25:c25:dd00:d5ab/1282c19:dd:d9:dd:c25:c25:dd00:d5ab
1732c19:dd:d9:dd:c25:c25:dd00:d5ac/1282c19:dd:d9:dd:c25:c25:dd00:d5ac
1742c19:dd:d9:dd:c25:c25:dd00:d5ad/1282c19:dd:d9:dd:c25:c25:dd00:d5ad
1752c19:dd:d9:dd:c25:c25:dd00:d5ae/1282c19:dd:d9:dd:c25:c25:dd00:d5ae
1762c19:dd:d9:dd:c25:c25:dd00:d5af/1282c19:dd:d9:dd:c25:c25:dd00:d5af
1772c19:dd:d9:dd:c25:c25:dd00:d5b0/1282c19:dd:d9:dd:c25:c25:dd00:d5b0
1782c19:dd:d9:dd:c25:c25:dd00:d5b1/1282c19:dd:d9:dd:c25:c25:dd00:d5b1
1792c19:dd:d9:dd:c25:c25:dd00:d5b2/1282c19:dd:d9:dd:c25:c25:dd00:d5b2
1802c19:dd:d9:dd:c25:c25:dd00:d5b3/1282c19:dd:d9:dd:c25:c25:dd00:d5b3
1812c19:dd:d9:dd:c25:c25:dd00:d5b4/1282c19:dd:d9:dd:c25:c25:dd00:d5b4
1822c19:dd:d9:dd:c25:c25:dd00:d5b5/1282c19:dd:d9:dd:c25:c25:dd00:d5b5
1832c19:dd:d9:dd:c25:c25:dd00:d5b6/1282c19:dd:d9:dd:c25:c25:dd00:d5b6
1842c19:dd:d9:dd:c25:c25:dd00:d5b7/1282c19:dd:d9:dd:c25:c25:dd00:d5b7
1852c19:dd:d9:dd:c25:c25:dd00:d5b8/1282c19:dd:d9:dd:c25:c25:dd00:d5b8
1862c19:dd:d9:dd:c25:c25:dd00:d5b9/1282c19:dd:d9:dd:c25:c25:dd00:d5b9
1872c19:dd:d9:dd:c25:c25:dd00:d5ba/1282c19:dd:d9:dd:c25:c25:dd00:d5ba
1882c19:dd:d9:dd:c25:c25:dd00:d5bb/1282c19:dd:d9:dd:c25:c25:dd00:d5bb
1892c19:dd:d9:dd:c25:c25:dd00:d5bc/1282c19:dd:d9:dd:c25:c25:dd00:d5bc
1902c19:dd:d9:dd:c25:c25:dd00:d5bd/1282c19:dd:d9:dd:c25:c25:dd00:d5bd
1912c19:dd:d9:dd:c25:c25:dd00:d5be/1282c19:dd:d9:dd:c25:c25:dd00:d5be
1922c19:dd:d9:dd:c25:c25:dd00:d5bf/1282c19:dd:d9:dd:c25:c25:dd00:d5bf
1932c19:dd:d9:dd:c25:c25:dd00:d5c0/1282c19:dd:d9:dd:c25:c25:dd00:d5c0
1942c19:dd:d9:dd:c25:c25:dd00:d5c1/1282c19:dd:d9:dd:c25:c25:dd00:d5c1
1952c19:dd:d9:dd:c25:c25:dd00:d5c2/1282c19:dd:d9:dd:c25:c25:dd00:d5c2
1962c19:dd:d9:dd:c25:c25:dd00:d5c3/1282c19:dd:d9:dd:c25:c25:dd00:d5c3
1972c19:dd:d9:dd:c25:c25:dd00:d5c4/1282c19:dd:d9:dd:c25:c25:dd00:d5c4
1982c19:dd:d9:dd:c25:c25:dd00:d5c5/1282c19:dd:d9:dd:c25:c25:dd00:d5c5
1992c19:dd:d9:dd:c25:c25:dd00:d5c6/1282c19:dd:d9:dd:c25:c25:dd00:d5c6
2002c19:dd:d9:dd:c25:c25:dd00:d5c7/1282c19:dd:d9:dd:c25:c25:dd00:d5c7
2012c19:dd:d9:dd:c25:c25:dd00:d5c8/1282c19:dd:d9:dd:c25:c25:dd00:d5c8
2022c19:dd:d9:dd:c25:c25:dd00:d5c9/1282c19:dd:d9:dd:c25:c25:dd00:d5c9
2032c19:dd:d9:dd:c25:c25:dd00:d5ca/1282c19:dd:d9:dd:c25:c25:dd00:d5ca
2042c19:dd:d9:dd:c25:c25:dd00:d5cb/1282c19:dd:d9:dd:c25:c25:dd00:d5cb
2052c19:dd:d9:dd:c25:c25:dd00:d5cc/1282c19:dd:d9:dd:c25:c25:dd00:d5cc
2062c19:dd:d9:dd:c25:c25:dd00:d5cd/1282c19:dd:d9:dd:c25:c25:dd00:d5cd
2072c19:dd:d9:dd:c25:c25:dd00:d5ce/1282c19:dd:d9:dd:c25:c25:dd00:d5ce
2082c19:dd:d9:dd:c25:c25:dd00:d5cf/1282c19:dd:d9:dd:c25:c25:dd00:d5cf
2092c19:dd:d9:dd:c25:c25:dd00:d5d0/1282c19:dd:d9:dd:c25:c25:dd00:d5d0
2102c19:dd:d9:dd:c25:c25:dd00:d5d1/1282c19:dd:d9:dd:c25:c25:dd00:d5d1
2112c19:dd:d9:dd:c25:c25:dd00:d5d2/1282c19:dd:d9:dd:c25:c25:dd00:d5d2
2122c19:dd:d9:dd:c25:c25:dd00:d5d3/1282c19:dd:d9:dd:c25:c25:dd00:d5d3
2132c19:dd:d9:dd:c25:c25:dd00:d5d4/1282c19:dd:d9:dd:c25:c25:dd00:d5d4
2142c19:dd:d9:dd:c25:c25:dd00:d5d5/1282c19:dd:d9:dd:c25:c25:dd00:d5d5
2152c19:dd:d9:dd:c25:c25:dd00:d5d6/1282c19:dd:d9:dd:c25:c25:dd00:d5d6
2162c19:dd:d9:dd:c25:c25:dd00:d5d7/1282c19:dd:d9:dd:c25:c25:dd00:d5d7
2172c19:dd:d9:dd:c25:c25:dd00:d5d8/1282c19:dd:d9:dd:c25:c25:dd00:d5d8
2182c19:dd:d9:dd:c25:c25:dd00:d5d9/1282c19:dd:d9:dd:c25:c25:dd00:d5d9
2192c19:dd:d9:dd:c25:c25:dd00:d5da/1282c19:dd:d9:dd:c25:c25:dd00:d5da
2202c19:dd:d9:dd:c25:c25:dd00:d5db/1282c19:dd:d9:dd:c25:c25:dd00:d5db
2212c19:dd:d9:dd:c25:c25:dd00:d5dc/1282c19:dd:d9:dd:c25:c25:dd00:d5dc
2222c19:dd:d9:dd:c25:c25:dd00:d5dd/1282c19:dd:d9:dd:c25:c25:dd00:d5dd
2232c19:dd:d9:dd:c25:c25:dd00:d5de/1282c19:dd:d9:dd:c25:c25:dd00:d5de
2242c19:dd:d9:dd:c25:c25:dd00:d5df/1282c19:dd:d9:dd:c25:c25:dd00:d5df
2252c19:dd:d9:dd:c25:c25:dd00:d5e0/1282c19:dd:d9:dd:c25:c25:dd00:d5e0
2262c19:dd:d9:dd:c25:c25:dd00:d5e1/1282c19:dd:d9:dd:c25:c25:dd00:d5e1
2272c19:dd:d9:dd:c25:c25:dd00:d5e2/1282c19:dd:d9:dd:c25:c25:dd00:d5e2
2282c19:dd:d9:dd:c25:c25:dd00:d5e3/1282c19:dd:d9:dd:c25:c25:dd00:d5e3
2292c19:dd:d9:dd:c25:c25:dd00:d5e4/1282c19:dd:d9:dd:c25:c25:dd00:d5e4
2302c19:dd:d9:dd:c25:c25:dd00:d5e5/1282c19:dd:d9:dd:c25:c25:dd00:d5e5
2312c19:dd:d9:dd:c25:c25:dd00:d5e6/1282c19:dd:d9:dd:c25:c25:dd00:d5e6
2322c19:dd:d9:dd:c25:c25:dd00:d5e7/1282c19:dd:d9:dd:c25:c25:dd00:d5e7
2332c19:dd:d9:dd:c25:c25:dd00:d5e8/1282c19:dd:d9:dd:c25:c25:dd00:d5e8
2342c19:dd:d9:dd:c25:c25:dd00:d5e9/1282c19:dd:d9:dd:c25:c25:dd00:d5e9
2352c19:dd:d9:dd:c25:c25:dd00:d5ea/1282c19:dd:d9:dd:c25:c25:dd00:d5ea
2362c19:dd:d9:dd:c25:c25:dd00:d5eb/1282c19:dd:d9:dd:c25:c25:dd00:d5eb
2372c19:dd:d9:dd:c25:c25:dd00:d5ec/1282c19:dd:d9:dd:c25:c25:dd00:d5ec
2382c19:dd:d9:dd:c25:c25:dd00:d5ed/1282c19:dd:d9:dd:c25:c25:dd00:d5ed
2392c19:dd:d9:dd:c25:c25:dd00:d5ee/1282c19:dd:d9:dd:c25:c25:dd00:d5ee
2402c19:dd:d9:dd:c25:c25:dd00:d5ef/1282c19:dd:d9:dd:c25:c25:dd00:d5ef
2412c19:dd:d9:dd:c25:c25:dd00:d5f0/1282c19:dd:d9:dd:c25:c25:dd00:d5f0
2422c19:dd:d9:dd:c25:c25:dd00:d5f1/1282c19:dd:d9:dd:c25:c25:dd00:d5f1
2432c19:dd:d9:dd:c25:c25:dd00:d5f2/1282c19:dd:d9:dd:c25:c25:dd00:d5f2
2442c19:dd:d9:dd:c25:c25:dd00:d5f3/1282c19:dd:d9:dd:c25:c25:dd00:d5f3
2452c19:dd:d9:dd:c25:c25:dd00:d5f4/1282c19:dd:d9:dd:c25:c25:dd00:d5f4
2462c19:dd:d9:dd:c25:c25:dd00:d5f5/1282c19:dd:d9:dd:c25:c25:dd00:d5f5
2472c19:dd:d9:dd:c25:c25:dd00:d5f6/1282c19:dd:d9:dd:c25:c25:dd00:d5f6
2482c19:dd:d9:dd:c25:c25:dd00:d5f7/1282c19:dd:d9:dd:c25:c25:dd00:d5f7
2492c19:dd:d9:dd:c25:c25:dd00:d5f8/1282c19:dd:d9:dd:c25:c25:dd00:d5f8
2502c19:dd:d9:dd:c25:c25:dd00:d5f9/1282c19:dd:d9:dd:c25:c25:dd00:d5f9
2512c19:dd:d9:dd:c25:c25:dd00:d5fa/1282c19:dd:d9:dd:c25:c25:dd00:d5fa
2522c19:dd:d9:dd:c25:c25:dd00:d5fb/1282c19:dd:d9:dd:c25:c25:dd00:d5fb
2532c19:dd:d9:dd:c25:c25:dd00:d5fc/1282c19:dd:d9:dd:c25:c25:dd00:d5fc
2542c19:dd:d9:dd:c25:c25:dd00:d5fd/1282c19:dd:d9:dd:c25:c25:dd00:d5fd
2552c19:dd:d9:dd:c25:c25:dd00:d5fe/1282c19:dd:d9:dd:c25:c25:dd00:d5fe
2562c19:dd:d9:dd:c25:c25:dd00:d5ff/1282c19:dd:d9:dd:c25:c25:dd00:d5ff

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.