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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:d915:f500/120
First address
2c19:dd:d9:dd:c25:c25:d915:f500
Last address
2c19:dd:d9:dd:c25:c25:d915:f5ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:f500
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.f.5.1.9.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:d915:f500/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:f500/1282c19:dd:d9:dd:c25:c25:d915:f500
22c19:dd:d9:dd:c25:c25:d915:f501/1282c19:dd:d9:dd:c25:c25:d915:f501
32c19:dd:d9:dd:c25:c25:d915:f502/1282c19:dd:d9:dd:c25:c25:d915:f502
42c19:dd:d9:dd:c25:c25:d915:f503/1282c19:dd:d9:dd:c25:c25:d915:f503
52c19:dd:d9:dd:c25:c25:d915:f504/1282c19:dd:d9:dd:c25:c25:d915:f504
62c19:dd:d9:dd:c25:c25:d915:f505/1282c19:dd:d9:dd:c25:c25:d915:f505
72c19:dd:d9:dd:c25:c25:d915:f506/1282c19:dd:d9:dd:c25:c25:d915:f506
82c19:dd:d9:dd:c25:c25:d915:f507/1282c19:dd:d9:dd:c25:c25:d915:f507
92c19:dd:d9:dd:c25:c25:d915:f508/1282c19:dd:d9:dd:c25:c25:d915:f508
102c19:dd:d9:dd:c25:c25:d915:f509/1282c19:dd:d9:dd:c25:c25:d915:f509
112c19:dd:d9:dd:c25:c25:d915:f50a/1282c19:dd:d9:dd:c25:c25:d915:f50a
122c19:dd:d9:dd:c25:c25:d915:f50b/1282c19:dd:d9:dd:c25:c25:d915:f50b
132c19:dd:d9:dd:c25:c25:d915:f50c/1282c19:dd:d9:dd:c25:c25:d915:f50c
142c19:dd:d9:dd:c25:c25:d915:f50d/1282c19:dd:d9:dd:c25:c25:d915:f50d
152c19:dd:d9:dd:c25:c25:d915:f50e/1282c19:dd:d9:dd:c25:c25:d915:f50e
162c19:dd:d9:dd:c25:c25:d915:f50f/1282c19:dd:d9:dd:c25:c25:d915:f50f
172c19:dd:d9:dd:c25:c25:d915:f510/1282c19:dd:d9:dd:c25:c25:d915:f510
182c19:dd:d9:dd:c25:c25:d915:f511/1282c19:dd:d9:dd:c25:c25:d915:f511
192c19:dd:d9:dd:c25:c25:d915:f512/1282c19:dd:d9:dd:c25:c25:d915:f512
202c19:dd:d9:dd:c25:c25:d915:f513/1282c19:dd:d9:dd:c25:c25:d915:f513
212c19:dd:d9:dd:c25:c25:d915:f514/1282c19:dd:d9:dd:c25:c25:d915:f514
222c19:dd:d9:dd:c25:c25:d915:f515/1282c19:dd:d9:dd:c25:c25:d915:f515
232c19:dd:d9:dd:c25:c25:d915:f516/1282c19:dd:d9:dd:c25:c25:d915:f516
242c19:dd:d9:dd:c25:c25:d915:f517/1282c19:dd:d9:dd:c25:c25:d915:f517
252c19:dd:d9:dd:c25:c25:d915:f518/1282c19:dd:d9:dd:c25:c25:d915:f518
262c19:dd:d9:dd:c25:c25:d915:f519/1282c19:dd:d9:dd:c25:c25:d915:f519
272c19:dd:d9:dd:c25:c25:d915:f51a/1282c19:dd:d9:dd:c25:c25:d915:f51a
282c19:dd:d9:dd:c25:c25:d915:f51b/1282c19:dd:d9:dd:c25:c25:d915:f51b
292c19:dd:d9:dd:c25:c25:d915:f51c/1282c19:dd:d9:dd:c25:c25:d915:f51c
302c19:dd:d9:dd:c25:c25:d915:f51d/1282c19:dd:d9:dd:c25:c25:d915:f51d
312c19:dd:d9:dd:c25:c25:d915:f51e/1282c19:dd:d9:dd:c25:c25:d915:f51e
322c19:dd:d9:dd:c25:c25:d915:f51f/1282c19:dd:d9:dd:c25:c25:d915:f51f
332c19:dd:d9:dd:c25:c25:d915:f520/1282c19:dd:d9:dd:c25:c25:d915:f520
342c19:dd:d9:dd:c25:c25:d915:f521/1282c19:dd:d9:dd:c25:c25:d915:f521
352c19:dd:d9:dd:c25:c25:d915:f522/1282c19:dd:d9:dd:c25:c25:d915:f522
362c19:dd:d9:dd:c25:c25:d915:f523/1282c19:dd:d9:dd:c25:c25:d915:f523
372c19:dd:d9:dd:c25:c25:d915:f524/1282c19:dd:d9:dd:c25:c25:d915:f524
382c19:dd:d9:dd:c25:c25:d915:f525/1282c19:dd:d9:dd:c25:c25:d915:f525
392c19:dd:d9:dd:c25:c25:d915:f526/1282c19:dd:d9:dd:c25:c25:d915:f526
402c19:dd:d9:dd:c25:c25:d915:f527/1282c19:dd:d9:dd:c25:c25:d915:f527
412c19:dd:d9:dd:c25:c25:d915:f528/1282c19:dd:d9:dd:c25:c25:d915:f528
422c19:dd:d9:dd:c25:c25:d915:f529/1282c19:dd:d9:dd:c25:c25:d915:f529
432c19:dd:d9:dd:c25:c25:d915:f52a/1282c19:dd:d9:dd:c25:c25:d915:f52a
442c19:dd:d9:dd:c25:c25:d915:f52b/1282c19:dd:d9:dd:c25:c25:d915:f52b
452c19:dd:d9:dd:c25:c25:d915:f52c/1282c19:dd:d9:dd:c25:c25:d915:f52c
462c19:dd:d9:dd:c25:c25:d915:f52d/1282c19:dd:d9:dd:c25:c25:d915:f52d
472c19:dd:d9:dd:c25:c25:d915:f52e/1282c19:dd:d9:dd:c25:c25:d915:f52e
482c19:dd:d9:dd:c25:c25:d915:f52f/1282c19:dd:d9:dd:c25:c25:d915:f52f
492c19:dd:d9:dd:c25:c25:d915:f530/1282c19:dd:d9:dd:c25:c25:d915:f530
502c19:dd:d9:dd:c25:c25:d915:f531/1282c19:dd:d9:dd:c25:c25:d915:f531
512c19:dd:d9:dd:c25:c25:d915:f532/1282c19:dd:d9:dd:c25:c25:d915:f532
522c19:dd:d9:dd:c25:c25:d915:f533/1282c19:dd:d9:dd:c25:c25:d915:f533
532c19:dd:d9:dd:c25:c25:d915:f534/1282c19:dd:d9:dd:c25:c25:d915:f534
542c19:dd:d9:dd:c25:c25:d915:f535/1282c19:dd:d9:dd:c25:c25:d915:f535
552c19:dd:d9:dd:c25:c25:d915:f536/1282c19:dd:d9:dd:c25:c25:d915:f536
562c19:dd:d9:dd:c25:c25:d915:f537/1282c19:dd:d9:dd:c25:c25:d915:f537
572c19:dd:d9:dd:c25:c25:d915:f538/1282c19:dd:d9:dd:c25:c25:d915:f538
582c19:dd:d9:dd:c25:c25:d915:f539/1282c19:dd:d9:dd:c25:c25:d915:f539
592c19:dd:d9:dd:c25:c25:d915:f53a/1282c19:dd:d9:dd:c25:c25:d915:f53a
602c19:dd:d9:dd:c25:c25:d915:f53b/1282c19:dd:d9:dd:c25:c25:d915:f53b
612c19:dd:d9:dd:c25:c25:d915:f53c/1282c19:dd:d9:dd:c25:c25:d915:f53c
622c19:dd:d9:dd:c25:c25:d915:f53d/1282c19:dd:d9:dd:c25:c25:d915:f53d
632c19:dd:d9:dd:c25:c25:d915:f53e/1282c19:dd:d9:dd:c25:c25:d915:f53e
642c19:dd:d9:dd:c25:c25:d915:f53f/1282c19:dd:d9:dd:c25:c25:d915:f53f
652c19:dd:d9:dd:c25:c25:d915:f540/1282c19:dd:d9:dd:c25:c25:d915:f540
662c19:dd:d9:dd:c25:c25:d915:f541/1282c19:dd:d9:dd:c25:c25:d915:f541
672c19:dd:d9:dd:c25:c25:d915:f542/1282c19:dd:d9:dd:c25:c25:d915:f542
682c19:dd:d9:dd:c25:c25:d915:f543/1282c19:dd:d9:dd:c25:c25:d915:f543
692c19:dd:d9:dd:c25:c25:d915:f544/1282c19:dd:d9:dd:c25:c25:d915:f544
702c19:dd:d9:dd:c25:c25:d915:f545/1282c19:dd:d9:dd:c25:c25:d915:f545
712c19:dd:d9:dd:c25:c25:d915:f546/1282c19:dd:d9:dd:c25:c25:d915:f546
722c19:dd:d9:dd:c25:c25:d915:f547/1282c19:dd:d9:dd:c25:c25:d915:f547
732c19:dd:d9:dd:c25:c25:d915:f548/1282c19:dd:d9:dd:c25:c25:d915:f548
742c19:dd:d9:dd:c25:c25:d915:f549/1282c19:dd:d9:dd:c25:c25:d915:f549
752c19:dd:d9:dd:c25:c25:d915:f54a/1282c19:dd:d9:dd:c25:c25:d915:f54a
762c19:dd:d9:dd:c25:c25:d915:f54b/1282c19:dd:d9:dd:c25:c25:d915:f54b
772c19:dd:d9:dd:c25:c25:d915:f54c/1282c19:dd:d9:dd:c25:c25:d915:f54c
782c19:dd:d9:dd:c25:c25:d915:f54d/1282c19:dd:d9:dd:c25:c25:d915:f54d
792c19:dd:d9:dd:c25:c25:d915:f54e/1282c19:dd:d9:dd:c25:c25:d915:f54e
802c19:dd:d9:dd:c25:c25:d915:f54f/1282c19:dd:d9:dd:c25:c25:d915:f54f
812c19:dd:d9:dd:c25:c25:d915:f550/1282c19:dd:d9:dd:c25:c25:d915:f550
822c19:dd:d9:dd:c25:c25:d915:f551/1282c19:dd:d9:dd:c25:c25:d915:f551
832c19:dd:d9:dd:c25:c25:d915:f552/1282c19:dd:d9:dd:c25:c25:d915:f552
842c19:dd:d9:dd:c25:c25:d915:f553/1282c19:dd:d9:dd:c25:c25:d915:f553
852c19:dd:d9:dd:c25:c25:d915:f554/1282c19:dd:d9:dd:c25:c25:d915:f554
862c19:dd:d9:dd:c25:c25:d915:f555/1282c19:dd:d9:dd:c25:c25:d915:f555
872c19:dd:d9:dd:c25:c25:d915:f556/1282c19:dd:d9:dd:c25:c25:d915:f556
882c19:dd:d9:dd:c25:c25:d915:f557/1282c19:dd:d9:dd:c25:c25:d915:f557
892c19:dd:d9:dd:c25:c25:d915:f558/1282c19:dd:d9:dd:c25:c25:d915:f558
902c19:dd:d9:dd:c25:c25:d915:f559/1282c19:dd:d9:dd:c25:c25:d915:f559
912c19:dd:d9:dd:c25:c25:d915:f55a/1282c19:dd:d9:dd:c25:c25:d915:f55a
922c19:dd:d9:dd:c25:c25:d915:f55b/1282c19:dd:d9:dd:c25:c25:d915:f55b
932c19:dd:d9:dd:c25:c25:d915:f55c/1282c19:dd:d9:dd:c25:c25:d915:f55c
942c19:dd:d9:dd:c25:c25:d915:f55d/1282c19:dd:d9:dd:c25:c25:d915:f55d
952c19:dd:d9:dd:c25:c25:d915:f55e/1282c19:dd:d9:dd:c25:c25:d915:f55e
962c19:dd:d9:dd:c25:c25:d915:f55f/1282c19:dd:d9:dd:c25:c25:d915:f55f
972c19:dd:d9:dd:c25:c25:d915:f560/1282c19:dd:d9:dd:c25:c25:d915:f560
982c19:dd:d9:dd:c25:c25:d915:f561/1282c19:dd:d9:dd:c25:c25:d915:f561
992c19:dd:d9:dd:c25:c25:d915:f562/1282c19:dd:d9:dd:c25:c25:d915:f562
1002c19:dd:d9:dd:c25:c25:d915:f563/1282c19:dd:d9:dd:c25:c25:d915:f563
1012c19:dd:d9:dd:c25:c25:d915:f564/1282c19:dd:d9:dd:c25:c25:d915:f564
1022c19:dd:d9:dd:c25:c25:d915:f565/1282c19:dd:d9:dd:c25:c25:d915:f565
1032c19:dd:d9:dd:c25:c25:d915:f566/1282c19:dd:d9:dd:c25:c25:d915:f566
1042c19:dd:d9:dd:c25:c25:d915:f567/1282c19:dd:d9:dd:c25:c25:d915:f567
1052c19:dd:d9:dd:c25:c25:d915:f568/1282c19:dd:d9:dd:c25:c25:d915:f568
1062c19:dd:d9:dd:c25:c25:d915:f569/1282c19:dd:d9:dd:c25:c25:d915:f569
1072c19:dd:d9:dd:c25:c25:d915:f56a/1282c19:dd:d9:dd:c25:c25:d915:f56a
1082c19:dd:d9:dd:c25:c25:d915:f56b/1282c19:dd:d9:dd:c25:c25:d915:f56b
1092c19:dd:d9:dd:c25:c25:d915:f56c/1282c19:dd:d9:dd:c25:c25:d915:f56c
1102c19:dd:d9:dd:c25:c25:d915:f56d/1282c19:dd:d9:dd:c25:c25:d915:f56d
1112c19:dd:d9:dd:c25:c25:d915:f56e/1282c19:dd:d9:dd:c25:c25:d915:f56e
1122c19:dd:d9:dd:c25:c25:d915:f56f/1282c19:dd:d9:dd:c25:c25:d915:f56f
1132c19:dd:d9:dd:c25:c25:d915:f570/1282c19:dd:d9:dd:c25:c25:d915:f570
1142c19:dd:d9:dd:c25:c25:d915:f571/1282c19:dd:d9:dd:c25:c25:d915:f571
1152c19:dd:d9:dd:c25:c25:d915:f572/1282c19:dd:d9:dd:c25:c25:d915:f572
1162c19:dd:d9:dd:c25:c25:d915:f573/1282c19:dd:d9:dd:c25:c25:d915:f573
1172c19:dd:d9:dd:c25:c25:d915:f574/1282c19:dd:d9:dd:c25:c25:d915:f574
1182c19:dd:d9:dd:c25:c25:d915:f575/1282c19:dd:d9:dd:c25:c25:d915:f575
1192c19:dd:d9:dd:c25:c25:d915:f576/1282c19:dd:d9:dd:c25:c25:d915:f576
1202c19:dd:d9:dd:c25:c25:d915:f577/1282c19:dd:d9:dd:c25:c25:d915:f577
1212c19:dd:d9:dd:c25:c25:d915:f578/1282c19:dd:d9:dd:c25:c25:d915:f578
1222c19:dd:d9:dd:c25:c25:d915:f579/1282c19:dd:d9:dd:c25:c25:d915:f579
1232c19:dd:d9:dd:c25:c25:d915:f57a/1282c19:dd:d9:dd:c25:c25:d915:f57a
1242c19:dd:d9:dd:c25:c25:d915:f57b/1282c19:dd:d9:dd:c25:c25:d915:f57b
1252c19:dd:d9:dd:c25:c25:d915:f57c/1282c19:dd:d9:dd:c25:c25:d915:f57c
1262c19:dd:d9:dd:c25:c25:d915:f57d/1282c19:dd:d9:dd:c25:c25:d915:f57d
1272c19:dd:d9:dd:c25:c25:d915:f57e/1282c19:dd:d9:dd:c25:c25:d915:f57e
1282c19:dd:d9:dd:c25:c25:d915:f57f/1282c19:dd:d9:dd:c25:c25:d915:f57f
1292c19:dd:d9:dd:c25:c25:d915:f580/1282c19:dd:d9:dd:c25:c25:d915:f580
1302c19:dd:d9:dd:c25:c25:d915:f581/1282c19:dd:d9:dd:c25:c25:d915:f581
1312c19:dd:d9:dd:c25:c25:d915:f582/1282c19:dd:d9:dd:c25:c25:d915:f582
1322c19:dd:d9:dd:c25:c25:d915:f583/1282c19:dd:d9:dd:c25:c25:d915:f583
1332c19:dd:d9:dd:c25:c25:d915:f584/1282c19:dd:d9:dd:c25:c25:d915:f584
1342c19:dd:d9:dd:c25:c25:d915:f585/1282c19:dd:d9:dd:c25:c25:d915:f585
1352c19:dd:d9:dd:c25:c25:d915:f586/1282c19:dd:d9:dd:c25:c25:d915:f586
1362c19:dd:d9:dd:c25:c25:d915:f587/1282c19:dd:d9:dd:c25:c25:d915:f587
1372c19:dd:d9:dd:c25:c25:d915:f588/1282c19:dd:d9:dd:c25:c25:d915:f588
1382c19:dd:d9:dd:c25:c25:d915:f589/1282c19:dd:d9:dd:c25:c25:d915:f589
1392c19:dd:d9:dd:c25:c25:d915:f58a/1282c19:dd:d9:dd:c25:c25:d915:f58a
1402c19:dd:d9:dd:c25:c25:d915:f58b/1282c19:dd:d9:dd:c25:c25:d915:f58b
1412c19:dd:d9:dd:c25:c25:d915:f58c/1282c19:dd:d9:dd:c25:c25:d915:f58c
1422c19:dd:d9:dd:c25:c25:d915:f58d/1282c19:dd:d9:dd:c25:c25:d915:f58d
1432c19:dd:d9:dd:c25:c25:d915:f58e/1282c19:dd:d9:dd:c25:c25:d915:f58e
1442c19:dd:d9:dd:c25:c25:d915:f58f/1282c19:dd:d9:dd:c25:c25:d915:f58f
1452c19:dd:d9:dd:c25:c25:d915:f590/1282c19:dd:d9:dd:c25:c25:d915:f590
1462c19:dd:d9:dd:c25:c25:d915:f591/1282c19:dd:d9:dd:c25:c25:d915:f591
1472c19:dd:d9:dd:c25:c25:d915:f592/1282c19:dd:d9:dd:c25:c25:d915:f592
1482c19:dd:d9:dd:c25:c25:d915:f593/1282c19:dd:d9:dd:c25:c25:d915:f593
1492c19:dd:d9:dd:c25:c25:d915:f594/1282c19:dd:d9:dd:c25:c25:d915:f594
1502c19:dd:d9:dd:c25:c25:d915:f595/1282c19:dd:d9:dd:c25:c25:d915:f595
1512c19:dd:d9:dd:c25:c25:d915:f596/1282c19:dd:d9:dd:c25:c25:d915:f596
1522c19:dd:d9:dd:c25:c25:d915:f597/1282c19:dd:d9:dd:c25:c25:d915:f597
1532c19:dd:d9:dd:c25:c25:d915:f598/1282c19:dd:d9:dd:c25:c25:d915:f598
1542c19:dd:d9:dd:c25:c25:d915:f599/1282c19:dd:d9:dd:c25:c25:d915:f599
1552c19:dd:d9:dd:c25:c25:d915:f59a/1282c19:dd:d9:dd:c25:c25:d915:f59a
1562c19:dd:d9:dd:c25:c25:d915:f59b/1282c19:dd:d9:dd:c25:c25:d915:f59b
1572c19:dd:d9:dd:c25:c25:d915:f59c/1282c19:dd:d9:dd:c25:c25:d915:f59c
1582c19:dd:d9:dd:c25:c25:d915:f59d/1282c19:dd:d9:dd:c25:c25:d915:f59d
1592c19:dd:d9:dd:c25:c25:d915:f59e/1282c19:dd:d9:dd:c25:c25:d915:f59e
1602c19:dd:d9:dd:c25:c25:d915:f59f/1282c19:dd:d9:dd:c25:c25:d915:f59f
1612c19:dd:d9:dd:c25:c25:d915:f5a0/1282c19:dd:d9:dd:c25:c25:d915:f5a0
1622c19:dd:d9:dd:c25:c25:d915:f5a1/1282c19:dd:d9:dd:c25:c25:d915:f5a1
1632c19:dd:d9:dd:c25:c25:d915:f5a2/1282c19:dd:d9:dd:c25:c25:d915:f5a2
1642c19:dd:d9:dd:c25:c25:d915:f5a3/1282c19:dd:d9:dd:c25:c25:d915:f5a3
1652c19:dd:d9:dd:c25:c25:d915:f5a4/1282c19:dd:d9:dd:c25:c25:d915:f5a4
1662c19:dd:d9:dd:c25:c25:d915:f5a5/1282c19:dd:d9:dd:c25:c25:d915:f5a5
1672c19:dd:d9:dd:c25:c25:d915:f5a6/1282c19:dd:d9:dd:c25:c25:d915:f5a6
1682c19:dd:d9:dd:c25:c25:d915:f5a7/1282c19:dd:d9:dd:c25:c25:d915:f5a7
1692c19:dd:d9:dd:c25:c25:d915:f5a8/1282c19:dd:d9:dd:c25:c25:d915:f5a8
1702c19:dd:d9:dd:c25:c25:d915:f5a9/1282c19:dd:d9:dd:c25:c25:d915:f5a9
1712c19:dd:d9:dd:c25:c25:d915:f5aa/1282c19:dd:d9:dd:c25:c25:d915:f5aa
1722c19:dd:d9:dd:c25:c25:d915:f5ab/1282c19:dd:d9:dd:c25:c25:d915:f5ab
1732c19:dd:d9:dd:c25:c25:d915:f5ac/1282c19:dd:d9:dd:c25:c25:d915:f5ac
1742c19:dd:d9:dd:c25:c25:d915:f5ad/1282c19:dd:d9:dd:c25:c25:d915:f5ad
1752c19:dd:d9:dd:c25:c25:d915:f5ae/1282c19:dd:d9:dd:c25:c25:d915:f5ae
1762c19:dd:d9:dd:c25:c25:d915:f5af/1282c19:dd:d9:dd:c25:c25:d915:f5af
1772c19:dd:d9:dd:c25:c25:d915:f5b0/1282c19:dd:d9:dd:c25:c25:d915:f5b0
1782c19:dd:d9:dd:c25:c25:d915:f5b1/1282c19:dd:d9:dd:c25:c25:d915:f5b1
1792c19:dd:d9:dd:c25:c25:d915:f5b2/1282c19:dd:d9:dd:c25:c25:d915:f5b2
1802c19:dd:d9:dd:c25:c25:d915:f5b3/1282c19:dd:d9:dd:c25:c25:d915:f5b3
1812c19:dd:d9:dd:c25:c25:d915:f5b4/1282c19:dd:d9:dd:c25:c25:d915:f5b4
1822c19:dd:d9:dd:c25:c25:d915:f5b5/1282c19:dd:d9:dd:c25:c25:d915:f5b5
1832c19:dd:d9:dd:c25:c25:d915:f5b6/1282c19:dd:d9:dd:c25:c25:d915:f5b6
1842c19:dd:d9:dd:c25:c25:d915:f5b7/1282c19:dd:d9:dd:c25:c25:d915:f5b7
1852c19:dd:d9:dd:c25:c25:d915:f5b8/1282c19:dd:d9:dd:c25:c25:d915:f5b8
1862c19:dd:d9:dd:c25:c25:d915:f5b9/1282c19:dd:d9:dd:c25:c25:d915:f5b9
1872c19:dd:d9:dd:c25:c25:d915:f5ba/1282c19:dd:d9:dd:c25:c25:d915:f5ba
1882c19:dd:d9:dd:c25:c25:d915:f5bb/1282c19:dd:d9:dd:c25:c25:d915:f5bb
1892c19:dd:d9:dd:c25:c25:d915:f5bc/1282c19:dd:d9:dd:c25:c25:d915:f5bc
1902c19:dd:d9:dd:c25:c25:d915:f5bd/1282c19:dd:d9:dd:c25:c25:d915:f5bd
1912c19:dd:d9:dd:c25:c25:d915:f5be/1282c19:dd:d9:dd:c25:c25:d915:f5be
1922c19:dd:d9:dd:c25:c25:d915:f5bf/1282c19:dd:d9:dd:c25:c25:d915:f5bf
1932c19:dd:d9:dd:c25:c25:d915:f5c0/1282c19:dd:d9:dd:c25:c25:d915:f5c0
1942c19:dd:d9:dd:c25:c25:d915:f5c1/1282c19:dd:d9:dd:c25:c25:d915:f5c1
1952c19:dd:d9:dd:c25:c25:d915:f5c2/1282c19:dd:d9:dd:c25:c25:d915:f5c2
1962c19:dd:d9:dd:c25:c25:d915:f5c3/1282c19:dd:d9:dd:c25:c25:d915:f5c3
1972c19:dd:d9:dd:c25:c25:d915:f5c4/1282c19:dd:d9:dd:c25:c25:d915:f5c4
1982c19:dd:d9:dd:c25:c25:d915:f5c5/1282c19:dd:d9:dd:c25:c25:d915:f5c5
1992c19:dd:d9:dd:c25:c25:d915:f5c6/1282c19:dd:d9:dd:c25:c25:d915:f5c6
2002c19:dd:d9:dd:c25:c25:d915:f5c7/1282c19:dd:d9:dd:c25:c25:d915:f5c7
2012c19:dd:d9:dd:c25:c25:d915:f5c8/1282c19:dd:d9:dd:c25:c25:d915:f5c8
2022c19:dd:d9:dd:c25:c25:d915:f5c9/1282c19:dd:d9:dd:c25:c25:d915:f5c9
2032c19:dd:d9:dd:c25:c25:d915:f5ca/1282c19:dd:d9:dd:c25:c25:d915:f5ca
2042c19:dd:d9:dd:c25:c25:d915:f5cb/1282c19:dd:d9:dd:c25:c25:d915:f5cb
2052c19:dd:d9:dd:c25:c25:d915:f5cc/1282c19:dd:d9:dd:c25:c25:d915:f5cc
2062c19:dd:d9:dd:c25:c25:d915:f5cd/1282c19:dd:d9:dd:c25:c25:d915:f5cd
2072c19:dd:d9:dd:c25:c25:d915:f5ce/1282c19:dd:d9:dd:c25:c25:d915:f5ce
2082c19:dd:d9:dd:c25:c25:d915:f5cf/1282c19:dd:d9:dd:c25:c25:d915:f5cf
2092c19:dd:d9:dd:c25:c25:d915:f5d0/1282c19:dd:d9:dd:c25:c25:d915:f5d0
2102c19:dd:d9:dd:c25:c25:d915:f5d1/1282c19:dd:d9:dd:c25:c25:d915:f5d1
2112c19:dd:d9:dd:c25:c25:d915:f5d2/1282c19:dd:d9:dd:c25:c25:d915:f5d2
2122c19:dd:d9:dd:c25:c25:d915:f5d3/1282c19:dd:d9:dd:c25:c25:d915:f5d3
2132c19:dd:d9:dd:c25:c25:d915:f5d4/1282c19:dd:d9:dd:c25:c25:d915:f5d4
2142c19:dd:d9:dd:c25:c25:d915:f5d5/1282c19:dd:d9:dd:c25:c25:d915:f5d5
2152c19:dd:d9:dd:c25:c25:d915:f5d6/1282c19:dd:d9:dd:c25:c25:d915:f5d6
2162c19:dd:d9:dd:c25:c25:d915:f5d7/1282c19:dd:d9:dd:c25:c25:d915:f5d7
2172c19:dd:d9:dd:c25:c25:d915:f5d8/1282c19:dd:d9:dd:c25:c25:d915:f5d8
2182c19:dd:d9:dd:c25:c25:d915:f5d9/1282c19:dd:d9:dd:c25:c25:d915:f5d9
2192c19:dd:d9:dd:c25:c25:d915:f5da/1282c19:dd:d9:dd:c25:c25:d915:f5da
2202c19:dd:d9:dd:c25:c25:d915:f5db/1282c19:dd:d9:dd:c25:c25:d915:f5db
2212c19:dd:d9:dd:c25:c25:d915:f5dc/1282c19:dd:d9:dd:c25:c25:d915:f5dc
2222c19:dd:d9:dd:c25:c25:d915:f5dd/1282c19:dd:d9:dd:c25:c25:d915:f5dd
2232c19:dd:d9:dd:c25:c25:d915:f5de/1282c19:dd:d9:dd:c25:c25:d915:f5de
2242c19:dd:d9:dd:c25:c25:d915:f5df/1282c19:dd:d9:dd:c25:c25:d915:f5df
2252c19:dd:d9:dd:c25:c25:d915:f5e0/1282c19:dd:d9:dd:c25:c25:d915:f5e0
2262c19:dd:d9:dd:c25:c25:d915:f5e1/1282c19:dd:d9:dd:c25:c25:d915:f5e1
2272c19:dd:d9:dd:c25:c25:d915:f5e2/1282c19:dd:d9:dd:c25:c25:d915:f5e2
2282c19:dd:d9:dd:c25:c25:d915:f5e3/1282c19:dd:d9:dd:c25:c25:d915:f5e3
2292c19:dd:d9:dd:c25:c25:d915:f5e4/1282c19:dd:d9:dd:c25:c25:d915:f5e4
2302c19:dd:d9:dd:c25:c25:d915:f5e5/1282c19:dd:d9:dd:c25:c25:d915:f5e5
2312c19:dd:d9:dd:c25:c25:d915:f5e6/1282c19:dd:d9:dd:c25:c25:d915:f5e6
2322c19:dd:d9:dd:c25:c25:d915:f5e7/1282c19:dd:d9:dd:c25:c25:d915:f5e7
2332c19:dd:d9:dd:c25:c25:d915:f5e8/1282c19:dd:d9:dd:c25:c25:d915:f5e8
2342c19:dd:d9:dd:c25:c25:d915:f5e9/1282c19:dd:d9:dd:c25:c25:d915:f5e9
2352c19:dd:d9:dd:c25:c25:d915:f5ea/1282c19:dd:d9:dd:c25:c25:d915:f5ea
2362c19:dd:d9:dd:c25:c25:d915:f5eb/1282c19:dd:d9:dd:c25:c25:d915:f5eb
2372c19:dd:d9:dd:c25:c25:d915:f5ec/1282c19:dd:d9:dd:c25:c25:d915:f5ec
2382c19:dd:d9:dd:c25:c25:d915:f5ed/1282c19:dd:d9:dd:c25:c25:d915:f5ed
2392c19:dd:d9:dd:c25:c25:d915:f5ee/1282c19:dd:d9:dd:c25:c25:d915:f5ee
2402c19:dd:d9:dd:c25:c25:d915:f5ef/1282c19:dd:d9:dd:c25:c25:d915:f5ef
2412c19:dd:d9:dd:c25:c25:d915:f5f0/1282c19:dd:d9:dd:c25:c25:d915:f5f0
2422c19:dd:d9:dd:c25:c25:d915:f5f1/1282c19:dd:d9:dd:c25:c25:d915:f5f1
2432c19:dd:d9:dd:c25:c25:d915:f5f2/1282c19:dd:d9:dd:c25:c25:d915:f5f2
2442c19:dd:d9:dd:c25:c25:d915:f5f3/1282c19:dd:d9:dd:c25:c25:d915:f5f3
2452c19:dd:d9:dd:c25:c25:d915:f5f4/1282c19:dd:d9:dd:c25:c25:d915:f5f4
2462c19:dd:d9:dd:c25:c25:d915:f5f5/1282c19:dd:d9:dd:c25:c25:d915:f5f5
2472c19:dd:d9:dd:c25:c25:d915:f5f6/1282c19:dd:d9:dd:c25:c25:d915:f5f6
2482c19:dd:d9:dd:c25:c25:d915:f5f7/1282c19:dd:d9:dd:c25:c25:d915:f5f7
2492c19:dd:d9:dd:c25:c25:d915:f5f8/1282c19:dd:d9:dd:c25:c25:d915:f5f8
2502c19:dd:d9:dd:c25:c25:d915:f5f9/1282c19:dd:d9:dd:c25:c25:d915:f5f9
2512c19:dd:d9:dd:c25:c25:d915:f5fa/1282c19:dd:d9:dd:c25:c25:d915:f5fa
2522c19:dd:d9:dd:c25:c25:d915:f5fb/1282c19:dd:d9:dd:c25:c25:d915:f5fb
2532c19:dd:d9:dd:c25:c25:d915:f5fc/1282c19:dd:d9:dd:c25:c25:d915:f5fc
2542c19:dd:d9:dd:c25:c25:d915:f5fd/1282c19:dd:d9:dd:c25:c25:d915:f5fd
2552c19:dd:d9:dd:c25:c25:d915:f5fe/1282c19:dd:d9:dd:c25:c25:d915:f5fe
2562c19:dd:d9:dd:c25:c25:d915:f5ff/1282c19:dd:d9:dd:c25:c25:d915:f5ff

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.