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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:c25:94de:5500/120
First address
2c19:dd:d9:dd:c25:c25:94de:5500
Last address
2c19:dd:d9:dd:c25:c25:94de:55ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:5500
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.5.e.d.4.9.5.2.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:c25:94de:5500/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:5500/1282c19:dd:d9:dd:c25:c25:94de:5500
22c19:dd:d9:dd:c25:c25:94de:5501/1282c19:dd:d9:dd:c25:c25:94de:5501
32c19:dd:d9:dd:c25:c25:94de:5502/1282c19:dd:d9:dd:c25:c25:94de:5502
42c19:dd:d9:dd:c25:c25:94de:5503/1282c19:dd:d9:dd:c25:c25:94de:5503
52c19:dd:d9:dd:c25:c25:94de:5504/1282c19:dd:d9:dd:c25:c25:94de:5504
62c19:dd:d9:dd:c25:c25:94de:5505/1282c19:dd:d9:dd:c25:c25:94de:5505
72c19:dd:d9:dd:c25:c25:94de:5506/1282c19:dd:d9:dd:c25:c25:94de:5506
82c19:dd:d9:dd:c25:c25:94de:5507/1282c19:dd:d9:dd:c25:c25:94de:5507
92c19:dd:d9:dd:c25:c25:94de:5508/1282c19:dd:d9:dd:c25:c25:94de:5508
102c19:dd:d9:dd:c25:c25:94de:5509/1282c19:dd:d9:dd:c25:c25:94de:5509
112c19:dd:d9:dd:c25:c25:94de:550a/1282c19:dd:d9:dd:c25:c25:94de:550a
122c19:dd:d9:dd:c25:c25:94de:550b/1282c19:dd:d9:dd:c25:c25:94de:550b
132c19:dd:d9:dd:c25:c25:94de:550c/1282c19:dd:d9:dd:c25:c25:94de:550c
142c19:dd:d9:dd:c25:c25:94de:550d/1282c19:dd:d9:dd:c25:c25:94de:550d
152c19:dd:d9:dd:c25:c25:94de:550e/1282c19:dd:d9:dd:c25:c25:94de:550e
162c19:dd:d9:dd:c25:c25:94de:550f/1282c19:dd:d9:dd:c25:c25:94de:550f
172c19:dd:d9:dd:c25:c25:94de:5510/1282c19:dd:d9:dd:c25:c25:94de:5510
182c19:dd:d9:dd:c25:c25:94de:5511/1282c19:dd:d9:dd:c25:c25:94de:5511
192c19:dd:d9:dd:c25:c25:94de:5512/1282c19:dd:d9:dd:c25:c25:94de:5512
202c19:dd:d9:dd:c25:c25:94de:5513/1282c19:dd:d9:dd:c25:c25:94de:5513
212c19:dd:d9:dd:c25:c25:94de:5514/1282c19:dd:d9:dd:c25:c25:94de:5514
222c19:dd:d9:dd:c25:c25:94de:5515/1282c19:dd:d9:dd:c25:c25:94de:5515
232c19:dd:d9:dd:c25:c25:94de:5516/1282c19:dd:d9:dd:c25:c25:94de:5516
242c19:dd:d9:dd:c25:c25:94de:5517/1282c19:dd:d9:dd:c25:c25:94de:5517
252c19:dd:d9:dd:c25:c25:94de:5518/1282c19:dd:d9:dd:c25:c25:94de:5518
262c19:dd:d9:dd:c25:c25:94de:5519/1282c19:dd:d9:dd:c25:c25:94de:5519
272c19:dd:d9:dd:c25:c25:94de:551a/1282c19:dd:d9:dd:c25:c25:94de:551a
282c19:dd:d9:dd:c25:c25:94de:551b/1282c19:dd:d9:dd:c25:c25:94de:551b
292c19:dd:d9:dd:c25:c25:94de:551c/1282c19:dd:d9:dd:c25:c25:94de:551c
302c19:dd:d9:dd:c25:c25:94de:551d/1282c19:dd:d9:dd:c25:c25:94de:551d
312c19:dd:d9:dd:c25:c25:94de:551e/1282c19:dd:d9:dd:c25:c25:94de:551e
322c19:dd:d9:dd:c25:c25:94de:551f/1282c19:dd:d9:dd:c25:c25:94de:551f
332c19:dd:d9:dd:c25:c25:94de:5520/1282c19:dd:d9:dd:c25:c25:94de:5520
342c19:dd:d9:dd:c25:c25:94de:5521/1282c19:dd:d9:dd:c25:c25:94de:5521
352c19:dd:d9:dd:c25:c25:94de:5522/1282c19:dd:d9:dd:c25:c25:94de:5522
362c19:dd:d9:dd:c25:c25:94de:5523/1282c19:dd:d9:dd:c25:c25:94de:5523
372c19:dd:d9:dd:c25:c25:94de:5524/1282c19:dd:d9:dd:c25:c25:94de:5524
382c19:dd:d9:dd:c25:c25:94de:5525/1282c19:dd:d9:dd:c25:c25:94de:5525
392c19:dd:d9:dd:c25:c25:94de:5526/1282c19:dd:d9:dd:c25:c25:94de:5526
402c19:dd:d9:dd:c25:c25:94de:5527/1282c19:dd:d9:dd:c25:c25:94de:5527
412c19:dd:d9:dd:c25:c25:94de:5528/1282c19:dd:d9:dd:c25:c25:94de:5528
422c19:dd:d9:dd:c25:c25:94de:5529/1282c19:dd:d9:dd:c25:c25:94de:5529
432c19:dd:d9:dd:c25:c25:94de:552a/1282c19:dd:d9:dd:c25:c25:94de:552a
442c19:dd:d9:dd:c25:c25:94de:552b/1282c19:dd:d9:dd:c25:c25:94de:552b
452c19:dd:d9:dd:c25:c25:94de:552c/1282c19:dd:d9:dd:c25:c25:94de:552c
462c19:dd:d9:dd:c25:c25:94de:552d/1282c19:dd:d9:dd:c25:c25:94de:552d
472c19:dd:d9:dd:c25:c25:94de:552e/1282c19:dd:d9:dd:c25:c25:94de:552e
482c19:dd:d9:dd:c25:c25:94de:552f/1282c19:dd:d9:dd:c25:c25:94de:552f
492c19:dd:d9:dd:c25:c25:94de:5530/1282c19:dd:d9:dd:c25:c25:94de:5530
502c19:dd:d9:dd:c25:c25:94de:5531/1282c19:dd:d9:dd:c25:c25:94de:5531
512c19:dd:d9:dd:c25:c25:94de:5532/1282c19:dd:d9:dd:c25:c25:94de:5532
522c19:dd:d9:dd:c25:c25:94de:5533/1282c19:dd:d9:dd:c25:c25:94de:5533
532c19:dd:d9:dd:c25:c25:94de:5534/1282c19:dd:d9:dd:c25:c25:94de:5534
542c19:dd:d9:dd:c25:c25:94de:5535/1282c19:dd:d9:dd:c25:c25:94de:5535
552c19:dd:d9:dd:c25:c25:94de:5536/1282c19:dd:d9:dd:c25:c25:94de:5536
562c19:dd:d9:dd:c25:c25:94de:5537/1282c19:dd:d9:dd:c25:c25:94de:5537
572c19:dd:d9:dd:c25:c25:94de:5538/1282c19:dd:d9:dd:c25:c25:94de:5538
582c19:dd:d9:dd:c25:c25:94de:5539/1282c19:dd:d9:dd:c25:c25:94de:5539
592c19:dd:d9:dd:c25:c25:94de:553a/1282c19:dd:d9:dd:c25:c25:94de:553a
602c19:dd:d9:dd:c25:c25:94de:553b/1282c19:dd:d9:dd:c25:c25:94de:553b
612c19:dd:d9:dd:c25:c25:94de:553c/1282c19:dd:d9:dd:c25:c25:94de:553c
622c19:dd:d9:dd:c25:c25:94de:553d/1282c19:dd:d9:dd:c25:c25:94de:553d
632c19:dd:d9:dd:c25:c25:94de:553e/1282c19:dd:d9:dd:c25:c25:94de:553e
642c19:dd:d9:dd:c25:c25:94de:553f/1282c19:dd:d9:dd:c25:c25:94de:553f
652c19:dd:d9:dd:c25:c25:94de:5540/1282c19:dd:d9:dd:c25:c25:94de:5540
662c19:dd:d9:dd:c25:c25:94de:5541/1282c19:dd:d9:dd:c25:c25:94de:5541
672c19:dd:d9:dd:c25:c25:94de:5542/1282c19:dd:d9:dd:c25:c25:94de:5542
682c19:dd:d9:dd:c25:c25:94de:5543/1282c19:dd:d9:dd:c25:c25:94de:5543
692c19:dd:d9:dd:c25:c25:94de:5544/1282c19:dd:d9:dd:c25:c25:94de:5544
702c19:dd:d9:dd:c25:c25:94de:5545/1282c19:dd:d9:dd:c25:c25:94de:5545
712c19:dd:d9:dd:c25:c25:94de:5546/1282c19:dd:d9:dd:c25:c25:94de:5546
722c19:dd:d9:dd:c25:c25:94de:5547/1282c19:dd:d9:dd:c25:c25:94de:5547
732c19:dd:d9:dd:c25:c25:94de:5548/1282c19:dd:d9:dd:c25:c25:94de:5548
742c19:dd:d9:dd:c25:c25:94de:5549/1282c19:dd:d9:dd:c25:c25:94de:5549
752c19:dd:d9:dd:c25:c25:94de:554a/1282c19:dd:d9:dd:c25:c25:94de:554a
762c19:dd:d9:dd:c25:c25:94de:554b/1282c19:dd:d9:dd:c25:c25:94de:554b
772c19:dd:d9:dd:c25:c25:94de:554c/1282c19:dd:d9:dd:c25:c25:94de:554c
782c19:dd:d9:dd:c25:c25:94de:554d/1282c19:dd:d9:dd:c25:c25:94de:554d
792c19:dd:d9:dd:c25:c25:94de:554e/1282c19:dd:d9:dd:c25:c25:94de:554e
802c19:dd:d9:dd:c25:c25:94de:554f/1282c19:dd:d9:dd:c25:c25:94de:554f
812c19:dd:d9:dd:c25:c25:94de:5550/1282c19:dd:d9:dd:c25:c25:94de:5550
822c19:dd:d9:dd:c25:c25:94de:5551/1282c19:dd:d9:dd:c25:c25:94de:5551
832c19:dd:d9:dd:c25:c25:94de:5552/1282c19:dd:d9:dd:c25:c25:94de:5552
842c19:dd:d9:dd:c25:c25:94de:5553/1282c19:dd:d9:dd:c25:c25:94de:5553
852c19:dd:d9:dd:c25:c25:94de:5554/1282c19:dd:d9:dd:c25:c25:94de:5554
862c19:dd:d9:dd:c25:c25:94de:5555/1282c19:dd:d9:dd:c25:c25:94de:5555
872c19:dd:d9:dd:c25:c25:94de:5556/1282c19:dd:d9:dd:c25:c25:94de:5556
882c19:dd:d9:dd:c25:c25:94de:5557/1282c19:dd:d9:dd:c25:c25:94de:5557
892c19:dd:d9:dd:c25:c25:94de:5558/1282c19:dd:d9:dd:c25:c25:94de:5558
902c19:dd:d9:dd:c25:c25:94de:5559/1282c19:dd:d9:dd:c25:c25:94de:5559
912c19:dd:d9:dd:c25:c25:94de:555a/1282c19:dd:d9:dd:c25:c25:94de:555a
922c19:dd:d9:dd:c25:c25:94de:555b/1282c19:dd:d9:dd:c25:c25:94de:555b
932c19:dd:d9:dd:c25:c25:94de:555c/1282c19:dd:d9:dd:c25:c25:94de:555c
942c19:dd:d9:dd:c25:c25:94de:555d/1282c19:dd:d9:dd:c25:c25:94de:555d
952c19:dd:d9:dd:c25:c25:94de:555e/1282c19:dd:d9:dd:c25:c25:94de:555e
962c19:dd:d9:dd:c25:c25:94de:555f/1282c19:dd:d9:dd:c25:c25:94de:555f
972c19:dd:d9:dd:c25:c25:94de:5560/1282c19:dd:d9:dd:c25:c25:94de:5560
982c19:dd:d9:dd:c25:c25:94de:5561/1282c19:dd:d9:dd:c25:c25:94de:5561
992c19:dd:d9:dd:c25:c25:94de:5562/1282c19:dd:d9:dd:c25:c25:94de:5562
1002c19:dd:d9:dd:c25:c25:94de:5563/1282c19:dd:d9:dd:c25:c25:94de:5563
1012c19:dd:d9:dd:c25:c25:94de:5564/1282c19:dd:d9:dd:c25:c25:94de:5564
1022c19:dd:d9:dd:c25:c25:94de:5565/1282c19:dd:d9:dd:c25:c25:94de:5565
1032c19:dd:d9:dd:c25:c25:94de:5566/1282c19:dd:d9:dd:c25:c25:94de:5566
1042c19:dd:d9:dd:c25:c25:94de:5567/1282c19:dd:d9:dd:c25:c25:94de:5567
1052c19:dd:d9:dd:c25:c25:94de:5568/1282c19:dd:d9:dd:c25:c25:94de:5568
1062c19:dd:d9:dd:c25:c25:94de:5569/1282c19:dd:d9:dd:c25:c25:94de:5569
1072c19:dd:d9:dd:c25:c25:94de:556a/1282c19:dd:d9:dd:c25:c25:94de:556a
1082c19:dd:d9:dd:c25:c25:94de:556b/1282c19:dd:d9:dd:c25:c25:94de:556b
1092c19:dd:d9:dd:c25:c25:94de:556c/1282c19:dd:d9:dd:c25:c25:94de:556c
1102c19:dd:d9:dd:c25:c25:94de:556d/1282c19:dd:d9:dd:c25:c25:94de:556d
1112c19:dd:d9:dd:c25:c25:94de:556e/1282c19:dd:d9:dd:c25:c25:94de:556e
1122c19:dd:d9:dd:c25:c25:94de:556f/1282c19:dd:d9:dd:c25:c25:94de:556f
1132c19:dd:d9:dd:c25:c25:94de:5570/1282c19:dd:d9:dd:c25:c25:94de:5570
1142c19:dd:d9:dd:c25:c25:94de:5571/1282c19:dd:d9:dd:c25:c25:94de:5571
1152c19:dd:d9:dd:c25:c25:94de:5572/1282c19:dd:d9:dd:c25:c25:94de:5572
1162c19:dd:d9:dd:c25:c25:94de:5573/1282c19:dd:d9:dd:c25:c25:94de:5573
1172c19:dd:d9:dd:c25:c25:94de:5574/1282c19:dd:d9:dd:c25:c25:94de:5574
1182c19:dd:d9:dd:c25:c25:94de:5575/1282c19:dd:d9:dd:c25:c25:94de:5575
1192c19:dd:d9:dd:c25:c25:94de:5576/1282c19:dd:d9:dd:c25:c25:94de:5576
1202c19:dd:d9:dd:c25:c25:94de:5577/1282c19:dd:d9:dd:c25:c25:94de:5577
1212c19:dd:d9:dd:c25:c25:94de:5578/1282c19:dd:d9:dd:c25:c25:94de:5578
1222c19:dd:d9:dd:c25:c25:94de:5579/1282c19:dd:d9:dd:c25:c25:94de:5579
1232c19:dd:d9:dd:c25:c25:94de:557a/1282c19:dd:d9:dd:c25:c25:94de:557a
1242c19:dd:d9:dd:c25:c25:94de:557b/1282c19:dd:d9:dd:c25:c25:94de:557b
1252c19:dd:d9:dd:c25:c25:94de:557c/1282c19:dd:d9:dd:c25:c25:94de:557c
1262c19:dd:d9:dd:c25:c25:94de:557d/1282c19:dd:d9:dd:c25:c25:94de:557d
1272c19:dd:d9:dd:c25:c25:94de:557e/1282c19:dd:d9:dd:c25:c25:94de:557e
1282c19:dd:d9:dd:c25:c25:94de:557f/1282c19:dd:d9:dd:c25:c25:94de:557f
1292c19:dd:d9:dd:c25:c25:94de:5580/1282c19:dd:d9:dd:c25:c25:94de:5580
1302c19:dd:d9:dd:c25:c25:94de:5581/1282c19:dd:d9:dd:c25:c25:94de:5581
1312c19:dd:d9:dd:c25:c25:94de:5582/1282c19:dd:d9:dd:c25:c25:94de:5582
1322c19:dd:d9:dd:c25:c25:94de:5583/1282c19:dd:d9:dd:c25:c25:94de:5583
1332c19:dd:d9:dd:c25:c25:94de:5584/1282c19:dd:d9:dd:c25:c25:94de:5584
1342c19:dd:d9:dd:c25:c25:94de:5585/1282c19:dd:d9:dd:c25:c25:94de:5585
1352c19:dd:d9:dd:c25:c25:94de:5586/1282c19:dd:d9:dd:c25:c25:94de:5586
1362c19:dd:d9:dd:c25:c25:94de:5587/1282c19:dd:d9:dd:c25:c25:94de:5587
1372c19:dd:d9:dd:c25:c25:94de:5588/1282c19:dd:d9:dd:c25:c25:94de:5588
1382c19:dd:d9:dd:c25:c25:94de:5589/1282c19:dd:d9:dd:c25:c25:94de:5589
1392c19:dd:d9:dd:c25:c25:94de:558a/1282c19:dd:d9:dd:c25:c25:94de:558a
1402c19:dd:d9:dd:c25:c25:94de:558b/1282c19:dd:d9:dd:c25:c25:94de:558b
1412c19:dd:d9:dd:c25:c25:94de:558c/1282c19:dd:d9:dd:c25:c25:94de:558c
1422c19:dd:d9:dd:c25:c25:94de:558d/1282c19:dd:d9:dd:c25:c25:94de:558d
1432c19:dd:d9:dd:c25:c25:94de:558e/1282c19:dd:d9:dd:c25:c25:94de:558e
1442c19:dd:d9:dd:c25:c25:94de:558f/1282c19:dd:d9:dd:c25:c25:94de:558f
1452c19:dd:d9:dd:c25:c25:94de:5590/1282c19:dd:d9:dd:c25:c25:94de:5590
1462c19:dd:d9:dd:c25:c25:94de:5591/1282c19:dd:d9:dd:c25:c25:94de:5591
1472c19:dd:d9:dd:c25:c25:94de:5592/1282c19:dd:d9:dd:c25:c25:94de:5592
1482c19:dd:d9:dd:c25:c25:94de:5593/1282c19:dd:d9:dd:c25:c25:94de:5593
1492c19:dd:d9:dd:c25:c25:94de:5594/1282c19:dd:d9:dd:c25:c25:94de:5594
1502c19:dd:d9:dd:c25:c25:94de:5595/1282c19:dd:d9:dd:c25:c25:94de:5595
1512c19:dd:d9:dd:c25:c25:94de:5596/1282c19:dd:d9:dd:c25:c25:94de:5596
1522c19:dd:d9:dd:c25:c25:94de:5597/1282c19:dd:d9:dd:c25:c25:94de:5597
1532c19:dd:d9:dd:c25:c25:94de:5598/1282c19:dd:d9:dd:c25:c25:94de:5598
1542c19:dd:d9:dd:c25:c25:94de:5599/1282c19:dd:d9:dd:c25:c25:94de:5599
1552c19:dd:d9:dd:c25:c25:94de:559a/1282c19:dd:d9:dd:c25:c25:94de:559a
1562c19:dd:d9:dd:c25:c25:94de:559b/1282c19:dd:d9:dd:c25:c25:94de:559b
1572c19:dd:d9:dd:c25:c25:94de:559c/1282c19:dd:d9:dd:c25:c25:94de:559c
1582c19:dd:d9:dd:c25:c25:94de:559d/1282c19:dd:d9:dd:c25:c25:94de:559d
1592c19:dd:d9:dd:c25:c25:94de:559e/1282c19:dd:d9:dd:c25:c25:94de:559e
1602c19:dd:d9:dd:c25:c25:94de:559f/1282c19:dd:d9:dd:c25:c25:94de:559f
1612c19:dd:d9:dd:c25:c25:94de:55a0/1282c19:dd:d9:dd:c25:c25:94de:55a0
1622c19:dd:d9:dd:c25:c25:94de:55a1/1282c19:dd:d9:dd:c25:c25:94de:55a1
1632c19:dd:d9:dd:c25:c25:94de:55a2/1282c19:dd:d9:dd:c25:c25:94de:55a2
1642c19:dd:d9:dd:c25:c25:94de:55a3/1282c19:dd:d9:dd:c25:c25:94de:55a3
1652c19:dd:d9:dd:c25:c25:94de:55a4/1282c19:dd:d9:dd:c25:c25:94de:55a4
1662c19:dd:d9:dd:c25:c25:94de:55a5/1282c19:dd:d9:dd:c25:c25:94de:55a5
1672c19:dd:d9:dd:c25:c25:94de:55a6/1282c19:dd:d9:dd:c25:c25:94de:55a6
1682c19:dd:d9:dd:c25:c25:94de:55a7/1282c19:dd:d9:dd:c25:c25:94de:55a7
1692c19:dd:d9:dd:c25:c25:94de:55a8/1282c19:dd:d9:dd:c25:c25:94de:55a8
1702c19:dd:d9:dd:c25:c25:94de:55a9/1282c19:dd:d9:dd:c25:c25:94de:55a9
1712c19:dd:d9:dd:c25:c25:94de:55aa/1282c19:dd:d9:dd:c25:c25:94de:55aa
1722c19:dd:d9:dd:c25:c25:94de:55ab/1282c19:dd:d9:dd:c25:c25:94de:55ab
1732c19:dd:d9:dd:c25:c25:94de:55ac/1282c19:dd:d9:dd:c25:c25:94de:55ac
1742c19:dd:d9:dd:c25:c25:94de:55ad/1282c19:dd:d9:dd:c25:c25:94de:55ad
1752c19:dd:d9:dd:c25:c25:94de:55ae/1282c19:dd:d9:dd:c25:c25:94de:55ae
1762c19:dd:d9:dd:c25:c25:94de:55af/1282c19:dd:d9:dd:c25:c25:94de:55af
1772c19:dd:d9:dd:c25:c25:94de:55b0/1282c19:dd:d9:dd:c25:c25:94de:55b0
1782c19:dd:d9:dd:c25:c25:94de:55b1/1282c19:dd:d9:dd:c25:c25:94de:55b1
1792c19:dd:d9:dd:c25:c25:94de:55b2/1282c19:dd:d9:dd:c25:c25:94de:55b2
1802c19:dd:d9:dd:c25:c25:94de:55b3/1282c19:dd:d9:dd:c25:c25:94de:55b3
1812c19:dd:d9:dd:c25:c25:94de:55b4/1282c19:dd:d9:dd:c25:c25:94de:55b4
1822c19:dd:d9:dd:c25:c25:94de:55b5/1282c19:dd:d9:dd:c25:c25:94de:55b5
1832c19:dd:d9:dd:c25:c25:94de:55b6/1282c19:dd:d9:dd:c25:c25:94de:55b6
1842c19:dd:d9:dd:c25:c25:94de:55b7/1282c19:dd:d9:dd:c25:c25:94de:55b7
1852c19:dd:d9:dd:c25:c25:94de:55b8/1282c19:dd:d9:dd:c25:c25:94de:55b8
1862c19:dd:d9:dd:c25:c25:94de:55b9/1282c19:dd:d9:dd:c25:c25:94de:55b9
1872c19:dd:d9:dd:c25:c25:94de:55ba/1282c19:dd:d9:dd:c25:c25:94de:55ba
1882c19:dd:d9:dd:c25:c25:94de:55bb/1282c19:dd:d9:dd:c25:c25:94de:55bb
1892c19:dd:d9:dd:c25:c25:94de:55bc/1282c19:dd:d9:dd:c25:c25:94de:55bc
1902c19:dd:d9:dd:c25:c25:94de:55bd/1282c19:dd:d9:dd:c25:c25:94de:55bd
1912c19:dd:d9:dd:c25:c25:94de:55be/1282c19:dd:d9:dd:c25:c25:94de:55be
1922c19:dd:d9:dd:c25:c25:94de:55bf/1282c19:dd:d9:dd:c25:c25:94de:55bf
1932c19:dd:d9:dd:c25:c25:94de:55c0/1282c19:dd:d9:dd:c25:c25:94de:55c0
1942c19:dd:d9:dd:c25:c25:94de:55c1/1282c19:dd:d9:dd:c25:c25:94de:55c1
1952c19:dd:d9:dd:c25:c25:94de:55c2/1282c19:dd:d9:dd:c25:c25:94de:55c2
1962c19:dd:d9:dd:c25:c25:94de:55c3/1282c19:dd:d9:dd:c25:c25:94de:55c3
1972c19:dd:d9:dd:c25:c25:94de:55c4/1282c19:dd:d9:dd:c25:c25:94de:55c4
1982c19:dd:d9:dd:c25:c25:94de:55c5/1282c19:dd:d9:dd:c25:c25:94de:55c5
1992c19:dd:d9:dd:c25:c25:94de:55c6/1282c19:dd:d9:dd:c25:c25:94de:55c6
2002c19:dd:d9:dd:c25:c25:94de:55c7/1282c19:dd:d9:dd:c25:c25:94de:55c7
2012c19:dd:d9:dd:c25:c25:94de:55c8/1282c19:dd:d9:dd:c25:c25:94de:55c8
2022c19:dd:d9:dd:c25:c25:94de:55c9/1282c19:dd:d9:dd:c25:c25:94de:55c9
2032c19:dd:d9:dd:c25:c25:94de:55ca/1282c19:dd:d9:dd:c25:c25:94de:55ca
2042c19:dd:d9:dd:c25:c25:94de:55cb/1282c19:dd:d9:dd:c25:c25:94de:55cb
2052c19:dd:d9:dd:c25:c25:94de:55cc/1282c19:dd:d9:dd:c25:c25:94de:55cc
2062c19:dd:d9:dd:c25:c25:94de:55cd/1282c19:dd:d9:dd:c25:c25:94de:55cd
2072c19:dd:d9:dd:c25:c25:94de:55ce/1282c19:dd:d9:dd:c25:c25:94de:55ce
2082c19:dd:d9:dd:c25:c25:94de:55cf/1282c19:dd:d9:dd:c25:c25:94de:55cf
2092c19:dd:d9:dd:c25:c25:94de:55d0/1282c19:dd:d9:dd:c25:c25:94de:55d0
2102c19:dd:d9:dd:c25:c25:94de:55d1/1282c19:dd:d9:dd:c25:c25:94de:55d1
2112c19:dd:d9:dd:c25:c25:94de:55d2/1282c19:dd:d9:dd:c25:c25:94de:55d2
2122c19:dd:d9:dd:c25:c25:94de:55d3/1282c19:dd:d9:dd:c25:c25:94de:55d3
2132c19:dd:d9:dd:c25:c25:94de:55d4/1282c19:dd:d9:dd:c25:c25:94de:55d4
2142c19:dd:d9:dd:c25:c25:94de:55d5/1282c19:dd:d9:dd:c25:c25:94de:55d5
2152c19:dd:d9:dd:c25:c25:94de:55d6/1282c19:dd:d9:dd:c25:c25:94de:55d6
2162c19:dd:d9:dd:c25:c25:94de:55d7/1282c19:dd:d9:dd:c25:c25:94de:55d7
2172c19:dd:d9:dd:c25:c25:94de:55d8/1282c19:dd:d9:dd:c25:c25:94de:55d8
2182c19:dd:d9:dd:c25:c25:94de:55d9/1282c19:dd:d9:dd:c25:c25:94de:55d9
2192c19:dd:d9:dd:c25:c25:94de:55da/1282c19:dd:d9:dd:c25:c25:94de:55da
2202c19:dd:d9:dd:c25:c25:94de:55db/1282c19:dd:d9:dd:c25:c25:94de:55db
2212c19:dd:d9:dd:c25:c25:94de:55dc/1282c19:dd:d9:dd:c25:c25:94de:55dc
2222c19:dd:d9:dd:c25:c25:94de:55dd/1282c19:dd:d9:dd:c25:c25:94de:55dd
2232c19:dd:d9:dd:c25:c25:94de:55de/1282c19:dd:d9:dd:c25:c25:94de:55de
2242c19:dd:d9:dd:c25:c25:94de:55df/1282c19:dd:d9:dd:c25:c25:94de:55df
2252c19:dd:d9:dd:c25:c25:94de:55e0/1282c19:dd:d9:dd:c25:c25:94de:55e0
2262c19:dd:d9:dd:c25:c25:94de:55e1/1282c19:dd:d9:dd:c25:c25:94de:55e1
2272c19:dd:d9:dd:c25:c25:94de:55e2/1282c19:dd:d9:dd:c25:c25:94de:55e2
2282c19:dd:d9:dd:c25:c25:94de:55e3/1282c19:dd:d9:dd:c25:c25:94de:55e3
2292c19:dd:d9:dd:c25:c25:94de:55e4/1282c19:dd:d9:dd:c25:c25:94de:55e4
2302c19:dd:d9:dd:c25:c25:94de:55e5/1282c19:dd:d9:dd:c25:c25:94de:55e5
2312c19:dd:d9:dd:c25:c25:94de:55e6/1282c19:dd:d9:dd:c25:c25:94de:55e6
2322c19:dd:d9:dd:c25:c25:94de:55e7/1282c19:dd:d9:dd:c25:c25:94de:55e7
2332c19:dd:d9:dd:c25:c25:94de:55e8/1282c19:dd:d9:dd:c25:c25:94de:55e8
2342c19:dd:d9:dd:c25:c25:94de:55e9/1282c19:dd:d9:dd:c25:c25:94de:55e9
2352c19:dd:d9:dd:c25:c25:94de:55ea/1282c19:dd:d9:dd:c25:c25:94de:55ea
2362c19:dd:d9:dd:c25:c25:94de:55eb/1282c19:dd:d9:dd:c25:c25:94de:55eb
2372c19:dd:d9:dd:c25:c25:94de:55ec/1282c19:dd:d9:dd:c25:c25:94de:55ec
2382c19:dd:d9:dd:c25:c25:94de:55ed/1282c19:dd:d9:dd:c25:c25:94de:55ed
2392c19:dd:d9:dd:c25:c25:94de:55ee/1282c19:dd:d9:dd:c25:c25:94de:55ee
2402c19:dd:d9:dd:c25:c25:94de:55ef/1282c19:dd:d9:dd:c25:c25:94de:55ef
2412c19:dd:d9:dd:c25:c25:94de:55f0/1282c19:dd:d9:dd:c25:c25:94de:55f0
2422c19:dd:d9:dd:c25:c25:94de:55f1/1282c19:dd:d9:dd:c25:c25:94de:55f1
2432c19:dd:d9:dd:c25:c25:94de:55f2/1282c19:dd:d9:dd:c25:c25:94de:55f2
2442c19:dd:d9:dd:c25:c25:94de:55f3/1282c19:dd:d9:dd:c25:c25:94de:55f3
2452c19:dd:d9:dd:c25:c25:94de:55f4/1282c19:dd:d9:dd:c25:c25:94de:55f4
2462c19:dd:d9:dd:c25:c25:94de:55f5/1282c19:dd:d9:dd:c25:c25:94de:55f5
2472c19:dd:d9:dd:c25:c25:94de:55f6/1282c19:dd:d9:dd:c25:c25:94de:55f6
2482c19:dd:d9:dd:c25:c25:94de:55f7/1282c19:dd:d9:dd:c25:c25:94de:55f7
2492c19:dd:d9:dd:c25:c25:94de:55f8/1282c19:dd:d9:dd:c25:c25:94de:55f8
2502c19:dd:d9:dd:c25:c25:94de:55f9/1282c19:dd:d9:dd:c25:c25:94de:55f9
2512c19:dd:d9:dd:c25:c25:94de:55fa/1282c19:dd:d9:dd:c25:c25:94de:55fa
2522c19:dd:d9:dd:c25:c25:94de:55fb/1282c19:dd:d9:dd:c25:c25:94de:55fb
2532c19:dd:d9:dd:c25:c25:94de:55fc/1282c19:dd:d9:dd:c25:c25:94de:55fc
2542c19:dd:d9:dd:c25:c25:94de:55fd/1282c19:dd:d9:dd:c25:c25:94de:55fd
2552c19:dd:d9:dd:c25:c25:94de:55fe/1282c19:dd:d9:dd:c25:c25:94de:55fe
2562c19:dd:d9:dd:c25:c25:94de:55ff/1282c19:dd:d9:dd:c25:c25:94de:55ff

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.