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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:c25b:d00a:a400/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:a400
Last address
2c19:dd:d9:dd:c25:c25b:d00a:a4ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:a400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.a.a.0.0.d.b.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:c25b:d00a:a400/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:a400/1282c19:dd:d9:dd:c25:c25b:d00a:a400
22c19:dd:d9:dd:c25:c25b:d00a:a401/1282c19:dd:d9:dd:c25:c25b:d00a:a401
32c19:dd:d9:dd:c25:c25b:d00a:a402/1282c19:dd:d9:dd:c25:c25b:d00a:a402
42c19:dd:d9:dd:c25:c25b:d00a:a403/1282c19:dd:d9:dd:c25:c25b:d00a:a403
52c19:dd:d9:dd:c25:c25b:d00a:a404/1282c19:dd:d9:dd:c25:c25b:d00a:a404
62c19:dd:d9:dd:c25:c25b:d00a:a405/1282c19:dd:d9:dd:c25:c25b:d00a:a405
72c19:dd:d9:dd:c25:c25b:d00a:a406/1282c19:dd:d9:dd:c25:c25b:d00a:a406
82c19:dd:d9:dd:c25:c25b:d00a:a407/1282c19:dd:d9:dd:c25:c25b:d00a:a407
92c19:dd:d9:dd:c25:c25b:d00a:a408/1282c19:dd:d9:dd:c25:c25b:d00a:a408
102c19:dd:d9:dd:c25:c25b:d00a:a409/1282c19:dd:d9:dd:c25:c25b:d00a:a409
112c19:dd:d9:dd:c25:c25b:d00a:a40a/1282c19:dd:d9:dd:c25:c25b:d00a:a40a
122c19:dd:d9:dd:c25:c25b:d00a:a40b/1282c19:dd:d9:dd:c25:c25b:d00a:a40b
132c19:dd:d9:dd:c25:c25b:d00a:a40c/1282c19:dd:d9:dd:c25:c25b:d00a:a40c
142c19:dd:d9:dd:c25:c25b:d00a:a40d/1282c19:dd:d9:dd:c25:c25b:d00a:a40d
152c19:dd:d9:dd:c25:c25b:d00a:a40e/1282c19:dd:d9:dd:c25:c25b:d00a:a40e
162c19:dd:d9:dd:c25:c25b:d00a:a40f/1282c19:dd:d9:dd:c25:c25b:d00a:a40f
172c19:dd:d9:dd:c25:c25b:d00a:a410/1282c19:dd:d9:dd:c25:c25b:d00a:a410
182c19:dd:d9:dd:c25:c25b:d00a:a411/1282c19:dd:d9:dd:c25:c25b:d00a:a411
192c19:dd:d9:dd:c25:c25b:d00a:a412/1282c19:dd:d9:dd:c25:c25b:d00a:a412
202c19:dd:d9:dd:c25:c25b:d00a:a413/1282c19:dd:d9:dd:c25:c25b:d00a:a413
212c19:dd:d9:dd:c25:c25b:d00a:a414/1282c19:dd:d9:dd:c25:c25b:d00a:a414
222c19:dd:d9:dd:c25:c25b:d00a:a415/1282c19:dd:d9:dd:c25:c25b:d00a:a415
232c19:dd:d9:dd:c25:c25b:d00a:a416/1282c19:dd:d9:dd:c25:c25b:d00a:a416
242c19:dd:d9:dd:c25:c25b:d00a:a417/1282c19:dd:d9:dd:c25:c25b:d00a:a417
252c19:dd:d9:dd:c25:c25b:d00a:a418/1282c19:dd:d9:dd:c25:c25b:d00a:a418
262c19:dd:d9:dd:c25:c25b:d00a:a419/1282c19:dd:d9:dd:c25:c25b:d00a:a419
272c19:dd:d9:dd:c25:c25b:d00a:a41a/1282c19:dd:d9:dd:c25:c25b:d00a:a41a
282c19:dd:d9:dd:c25:c25b:d00a:a41b/1282c19:dd:d9:dd:c25:c25b:d00a:a41b
292c19:dd:d9:dd:c25:c25b:d00a:a41c/1282c19:dd:d9:dd:c25:c25b:d00a:a41c
302c19:dd:d9:dd:c25:c25b:d00a:a41d/1282c19:dd:d9:dd:c25:c25b:d00a:a41d
312c19:dd:d9:dd:c25:c25b:d00a:a41e/1282c19:dd:d9:dd:c25:c25b:d00a:a41e
322c19:dd:d9:dd:c25:c25b:d00a:a41f/1282c19:dd:d9:dd:c25:c25b:d00a:a41f
332c19:dd:d9:dd:c25:c25b:d00a:a420/1282c19:dd:d9:dd:c25:c25b:d00a:a420
342c19:dd:d9:dd:c25:c25b:d00a:a421/1282c19:dd:d9:dd:c25:c25b:d00a:a421
352c19:dd:d9:dd:c25:c25b:d00a:a422/1282c19:dd:d9:dd:c25:c25b:d00a:a422
362c19:dd:d9:dd:c25:c25b:d00a:a423/1282c19:dd:d9:dd:c25:c25b:d00a:a423
372c19:dd:d9:dd:c25:c25b:d00a:a424/1282c19:dd:d9:dd:c25:c25b:d00a:a424
382c19:dd:d9:dd:c25:c25b:d00a:a425/1282c19:dd:d9:dd:c25:c25b:d00a:a425
392c19:dd:d9:dd:c25:c25b:d00a:a426/1282c19:dd:d9:dd:c25:c25b:d00a:a426
402c19:dd:d9:dd:c25:c25b:d00a:a427/1282c19:dd:d9:dd:c25:c25b:d00a:a427
412c19:dd:d9:dd:c25:c25b:d00a:a428/1282c19:dd:d9:dd:c25:c25b:d00a:a428
422c19:dd:d9:dd:c25:c25b:d00a:a429/1282c19:dd:d9:dd:c25:c25b:d00a:a429
432c19:dd:d9:dd:c25:c25b:d00a:a42a/1282c19:dd:d9:dd:c25:c25b:d00a:a42a
442c19:dd:d9:dd:c25:c25b:d00a:a42b/1282c19:dd:d9:dd:c25:c25b:d00a:a42b
452c19:dd:d9:dd:c25:c25b:d00a:a42c/1282c19:dd:d9:dd:c25:c25b:d00a:a42c
462c19:dd:d9:dd:c25:c25b:d00a:a42d/1282c19:dd:d9:dd:c25:c25b:d00a:a42d
472c19:dd:d9:dd:c25:c25b:d00a:a42e/1282c19:dd:d9:dd:c25:c25b:d00a:a42e
482c19:dd:d9:dd:c25:c25b:d00a:a42f/1282c19:dd:d9:dd:c25:c25b:d00a:a42f
492c19:dd:d9:dd:c25:c25b:d00a:a430/1282c19:dd:d9:dd:c25:c25b:d00a:a430
502c19:dd:d9:dd:c25:c25b:d00a:a431/1282c19:dd:d9:dd:c25:c25b:d00a:a431
512c19:dd:d9:dd:c25:c25b:d00a:a432/1282c19:dd:d9:dd:c25:c25b:d00a:a432
522c19:dd:d9:dd:c25:c25b:d00a:a433/1282c19:dd:d9:dd:c25:c25b:d00a:a433
532c19:dd:d9:dd:c25:c25b:d00a:a434/1282c19:dd:d9:dd:c25:c25b:d00a:a434
542c19:dd:d9:dd:c25:c25b:d00a:a435/1282c19:dd:d9:dd:c25:c25b:d00a:a435
552c19:dd:d9:dd:c25:c25b:d00a:a436/1282c19:dd:d9:dd:c25:c25b:d00a:a436
562c19:dd:d9:dd:c25:c25b:d00a:a437/1282c19:dd:d9:dd:c25:c25b:d00a:a437
572c19:dd:d9:dd:c25:c25b:d00a:a438/1282c19:dd:d9:dd:c25:c25b:d00a:a438
582c19:dd:d9:dd:c25:c25b:d00a:a439/1282c19:dd:d9:dd:c25:c25b:d00a:a439
592c19:dd:d9:dd:c25:c25b:d00a:a43a/1282c19:dd:d9:dd:c25:c25b:d00a:a43a
602c19:dd:d9:dd:c25:c25b:d00a:a43b/1282c19:dd:d9:dd:c25:c25b:d00a:a43b
612c19:dd:d9:dd:c25:c25b:d00a:a43c/1282c19:dd:d9:dd:c25:c25b:d00a:a43c
622c19:dd:d9:dd:c25:c25b:d00a:a43d/1282c19:dd:d9:dd:c25:c25b:d00a:a43d
632c19:dd:d9:dd:c25:c25b:d00a:a43e/1282c19:dd:d9:dd:c25:c25b:d00a:a43e
642c19:dd:d9:dd:c25:c25b:d00a:a43f/1282c19:dd:d9:dd:c25:c25b:d00a:a43f
652c19:dd:d9:dd:c25:c25b:d00a:a440/1282c19:dd:d9:dd:c25:c25b:d00a:a440
662c19:dd:d9:dd:c25:c25b:d00a:a441/1282c19:dd:d9:dd:c25:c25b:d00a:a441
672c19:dd:d9:dd:c25:c25b:d00a:a442/1282c19:dd:d9:dd:c25:c25b:d00a:a442
682c19:dd:d9:dd:c25:c25b:d00a:a443/1282c19:dd:d9:dd:c25:c25b:d00a:a443
692c19:dd:d9:dd:c25:c25b:d00a:a444/1282c19:dd:d9:dd:c25:c25b:d00a:a444
702c19:dd:d9:dd:c25:c25b:d00a:a445/1282c19:dd:d9:dd:c25:c25b:d00a:a445
712c19:dd:d9:dd:c25:c25b:d00a:a446/1282c19:dd:d9:dd:c25:c25b:d00a:a446
722c19:dd:d9:dd:c25:c25b:d00a:a447/1282c19:dd:d9:dd:c25:c25b:d00a:a447
732c19:dd:d9:dd:c25:c25b:d00a:a448/1282c19:dd:d9:dd:c25:c25b:d00a:a448
742c19:dd:d9:dd:c25:c25b:d00a:a449/1282c19:dd:d9:dd:c25:c25b:d00a:a449
752c19:dd:d9:dd:c25:c25b:d00a:a44a/1282c19:dd:d9:dd:c25:c25b:d00a:a44a
762c19:dd:d9:dd:c25:c25b:d00a:a44b/1282c19:dd:d9:dd:c25:c25b:d00a:a44b
772c19:dd:d9:dd:c25:c25b:d00a:a44c/1282c19:dd:d9:dd:c25:c25b:d00a:a44c
782c19:dd:d9:dd:c25:c25b:d00a:a44d/1282c19:dd:d9:dd:c25:c25b:d00a:a44d
792c19:dd:d9:dd:c25:c25b:d00a:a44e/1282c19:dd:d9:dd:c25:c25b:d00a:a44e
802c19:dd:d9:dd:c25:c25b:d00a:a44f/1282c19:dd:d9:dd:c25:c25b:d00a:a44f
812c19:dd:d9:dd:c25:c25b:d00a:a450/1282c19:dd:d9:dd:c25:c25b:d00a:a450
822c19:dd:d9:dd:c25:c25b:d00a:a451/1282c19:dd:d9:dd:c25:c25b:d00a:a451
832c19:dd:d9:dd:c25:c25b:d00a:a452/1282c19:dd:d9:dd:c25:c25b:d00a:a452
842c19:dd:d9:dd:c25:c25b:d00a:a453/1282c19:dd:d9:dd:c25:c25b:d00a:a453
852c19:dd:d9:dd:c25:c25b:d00a:a454/1282c19:dd:d9:dd:c25:c25b:d00a:a454
862c19:dd:d9:dd:c25:c25b:d00a:a455/1282c19:dd:d9:dd:c25:c25b:d00a:a455
872c19:dd:d9:dd:c25:c25b:d00a:a456/1282c19:dd:d9:dd:c25:c25b:d00a:a456
882c19:dd:d9:dd:c25:c25b:d00a:a457/1282c19:dd:d9:dd:c25:c25b:d00a:a457
892c19:dd:d9:dd:c25:c25b:d00a:a458/1282c19:dd:d9:dd:c25:c25b:d00a:a458
902c19:dd:d9:dd:c25:c25b:d00a:a459/1282c19:dd:d9:dd:c25:c25b:d00a:a459
912c19:dd:d9:dd:c25:c25b:d00a:a45a/1282c19:dd:d9:dd:c25:c25b:d00a:a45a
922c19:dd:d9:dd:c25:c25b:d00a:a45b/1282c19:dd:d9:dd:c25:c25b:d00a:a45b
932c19:dd:d9:dd:c25:c25b:d00a:a45c/1282c19:dd:d9:dd:c25:c25b:d00a:a45c
942c19:dd:d9:dd:c25:c25b:d00a:a45d/1282c19:dd:d9:dd:c25:c25b:d00a:a45d
952c19:dd:d9:dd:c25:c25b:d00a:a45e/1282c19:dd:d9:dd:c25:c25b:d00a:a45e
962c19:dd:d9:dd:c25:c25b:d00a:a45f/1282c19:dd:d9:dd:c25:c25b:d00a:a45f
972c19:dd:d9:dd:c25:c25b:d00a:a460/1282c19:dd:d9:dd:c25:c25b:d00a:a460
982c19:dd:d9:dd:c25:c25b:d00a:a461/1282c19:dd:d9:dd:c25:c25b:d00a:a461
992c19:dd:d9:dd:c25:c25b:d00a:a462/1282c19:dd:d9:dd:c25:c25b:d00a:a462
1002c19:dd:d9:dd:c25:c25b:d00a:a463/1282c19:dd:d9:dd:c25:c25b:d00a:a463
1012c19:dd:d9:dd:c25:c25b:d00a:a464/1282c19:dd:d9:dd:c25:c25b:d00a:a464
1022c19:dd:d9:dd:c25:c25b:d00a:a465/1282c19:dd:d9:dd:c25:c25b:d00a:a465
1032c19:dd:d9:dd:c25:c25b:d00a:a466/1282c19:dd:d9:dd:c25:c25b:d00a:a466
1042c19:dd:d9:dd:c25:c25b:d00a:a467/1282c19:dd:d9:dd:c25:c25b:d00a:a467
1052c19:dd:d9:dd:c25:c25b:d00a:a468/1282c19:dd:d9:dd:c25:c25b:d00a:a468
1062c19:dd:d9:dd:c25:c25b:d00a:a469/1282c19:dd:d9:dd:c25:c25b:d00a:a469
1072c19:dd:d9:dd:c25:c25b:d00a:a46a/1282c19:dd:d9:dd:c25:c25b:d00a:a46a
1082c19:dd:d9:dd:c25:c25b:d00a:a46b/1282c19:dd:d9:dd:c25:c25b:d00a:a46b
1092c19:dd:d9:dd:c25:c25b:d00a:a46c/1282c19:dd:d9:dd:c25:c25b:d00a:a46c
1102c19:dd:d9:dd:c25:c25b:d00a:a46d/1282c19:dd:d9:dd:c25:c25b:d00a:a46d
1112c19:dd:d9:dd:c25:c25b:d00a:a46e/1282c19:dd:d9:dd:c25:c25b:d00a:a46e
1122c19:dd:d9:dd:c25:c25b:d00a:a46f/1282c19:dd:d9:dd:c25:c25b:d00a:a46f
1132c19:dd:d9:dd:c25:c25b:d00a:a470/1282c19:dd:d9:dd:c25:c25b:d00a:a470
1142c19:dd:d9:dd:c25:c25b:d00a:a471/1282c19:dd:d9:dd:c25:c25b:d00a:a471
1152c19:dd:d9:dd:c25:c25b:d00a:a472/1282c19:dd:d9:dd:c25:c25b:d00a:a472
1162c19:dd:d9:dd:c25:c25b:d00a:a473/1282c19:dd:d9:dd:c25:c25b:d00a:a473
1172c19:dd:d9:dd:c25:c25b:d00a:a474/1282c19:dd:d9:dd:c25:c25b:d00a:a474
1182c19:dd:d9:dd:c25:c25b:d00a:a475/1282c19:dd:d9:dd:c25:c25b:d00a:a475
1192c19:dd:d9:dd:c25:c25b:d00a:a476/1282c19:dd:d9:dd:c25:c25b:d00a:a476
1202c19:dd:d9:dd:c25:c25b:d00a:a477/1282c19:dd:d9:dd:c25:c25b:d00a:a477
1212c19:dd:d9:dd:c25:c25b:d00a:a478/1282c19:dd:d9:dd:c25:c25b:d00a:a478
1222c19:dd:d9:dd:c25:c25b:d00a:a479/1282c19:dd:d9:dd:c25:c25b:d00a:a479
1232c19:dd:d9:dd:c25:c25b:d00a:a47a/1282c19:dd:d9:dd:c25:c25b:d00a:a47a
1242c19:dd:d9:dd:c25:c25b:d00a:a47b/1282c19:dd:d9:dd:c25:c25b:d00a:a47b
1252c19:dd:d9:dd:c25:c25b:d00a:a47c/1282c19:dd:d9:dd:c25:c25b:d00a:a47c
1262c19:dd:d9:dd:c25:c25b:d00a:a47d/1282c19:dd:d9:dd:c25:c25b:d00a:a47d
1272c19:dd:d9:dd:c25:c25b:d00a:a47e/1282c19:dd:d9:dd:c25:c25b:d00a:a47e
1282c19:dd:d9:dd:c25:c25b:d00a:a47f/1282c19:dd:d9:dd:c25:c25b:d00a:a47f
1292c19:dd:d9:dd:c25:c25b:d00a:a480/1282c19:dd:d9:dd:c25:c25b:d00a:a480
1302c19:dd:d9:dd:c25:c25b:d00a:a481/1282c19:dd:d9:dd:c25:c25b:d00a:a481
1312c19:dd:d9:dd:c25:c25b:d00a:a482/1282c19:dd:d9:dd:c25:c25b:d00a:a482
1322c19:dd:d9:dd:c25:c25b:d00a:a483/1282c19:dd:d9:dd:c25:c25b:d00a:a483
1332c19:dd:d9:dd:c25:c25b:d00a:a484/1282c19:dd:d9:dd:c25:c25b:d00a:a484
1342c19:dd:d9:dd:c25:c25b:d00a:a485/1282c19:dd:d9:dd:c25:c25b:d00a:a485
1352c19:dd:d9:dd:c25:c25b:d00a:a486/1282c19:dd:d9:dd:c25:c25b:d00a:a486
1362c19:dd:d9:dd:c25:c25b:d00a:a487/1282c19:dd:d9:dd:c25:c25b:d00a:a487
1372c19:dd:d9:dd:c25:c25b:d00a:a488/1282c19:dd:d9:dd:c25:c25b:d00a:a488
1382c19:dd:d9:dd:c25:c25b:d00a:a489/1282c19:dd:d9:dd:c25:c25b:d00a:a489
1392c19:dd:d9:dd:c25:c25b:d00a:a48a/1282c19:dd:d9:dd:c25:c25b:d00a:a48a
1402c19:dd:d9:dd:c25:c25b:d00a:a48b/1282c19:dd:d9:dd:c25:c25b:d00a:a48b
1412c19:dd:d9:dd:c25:c25b:d00a:a48c/1282c19:dd:d9:dd:c25:c25b:d00a:a48c
1422c19:dd:d9:dd:c25:c25b:d00a:a48d/1282c19:dd:d9:dd:c25:c25b:d00a:a48d
1432c19:dd:d9:dd:c25:c25b:d00a:a48e/1282c19:dd:d9:dd:c25:c25b:d00a:a48e
1442c19:dd:d9:dd:c25:c25b:d00a:a48f/1282c19:dd:d9:dd:c25:c25b:d00a:a48f
1452c19:dd:d9:dd:c25:c25b:d00a:a490/1282c19:dd:d9:dd:c25:c25b:d00a:a490
1462c19:dd:d9:dd:c25:c25b:d00a:a491/1282c19:dd:d9:dd:c25:c25b:d00a:a491
1472c19:dd:d9:dd:c25:c25b:d00a:a492/1282c19:dd:d9:dd:c25:c25b:d00a:a492
1482c19:dd:d9:dd:c25:c25b:d00a:a493/1282c19:dd:d9:dd:c25:c25b:d00a:a493
1492c19:dd:d9:dd:c25:c25b:d00a:a494/1282c19:dd:d9:dd:c25:c25b:d00a:a494
1502c19:dd:d9:dd:c25:c25b:d00a:a495/1282c19:dd:d9:dd:c25:c25b:d00a:a495
1512c19:dd:d9:dd:c25:c25b:d00a:a496/1282c19:dd:d9:dd:c25:c25b:d00a:a496
1522c19:dd:d9:dd:c25:c25b:d00a:a497/1282c19:dd:d9:dd:c25:c25b:d00a:a497
1532c19:dd:d9:dd:c25:c25b:d00a:a498/1282c19:dd:d9:dd:c25:c25b:d00a:a498
1542c19:dd:d9:dd:c25:c25b:d00a:a499/1282c19:dd:d9:dd:c25:c25b:d00a:a499
1552c19:dd:d9:dd:c25:c25b:d00a:a49a/1282c19:dd:d9:dd:c25:c25b:d00a:a49a
1562c19:dd:d9:dd:c25:c25b:d00a:a49b/1282c19:dd:d9:dd:c25:c25b:d00a:a49b
1572c19:dd:d9:dd:c25:c25b:d00a:a49c/1282c19:dd:d9:dd:c25:c25b:d00a:a49c
1582c19:dd:d9:dd:c25:c25b:d00a:a49d/1282c19:dd:d9:dd:c25:c25b:d00a:a49d
1592c19:dd:d9:dd:c25:c25b:d00a:a49e/1282c19:dd:d9:dd:c25:c25b:d00a:a49e
1602c19:dd:d9:dd:c25:c25b:d00a:a49f/1282c19:dd:d9:dd:c25:c25b:d00a:a49f
1612c19:dd:d9:dd:c25:c25b:d00a:a4a0/1282c19:dd:d9:dd:c25:c25b:d00a:a4a0
1622c19:dd:d9:dd:c25:c25b:d00a:a4a1/1282c19:dd:d9:dd:c25:c25b:d00a:a4a1
1632c19:dd:d9:dd:c25:c25b:d00a:a4a2/1282c19:dd:d9:dd:c25:c25b:d00a:a4a2
1642c19:dd:d9:dd:c25:c25b:d00a:a4a3/1282c19:dd:d9:dd:c25:c25b:d00a:a4a3
1652c19:dd:d9:dd:c25:c25b:d00a:a4a4/1282c19:dd:d9:dd:c25:c25b:d00a:a4a4
1662c19:dd:d9:dd:c25:c25b:d00a:a4a5/1282c19:dd:d9:dd:c25:c25b:d00a:a4a5
1672c19:dd:d9:dd:c25:c25b:d00a:a4a6/1282c19:dd:d9:dd:c25:c25b:d00a:a4a6
1682c19:dd:d9:dd:c25:c25b:d00a:a4a7/1282c19:dd:d9:dd:c25:c25b:d00a:a4a7
1692c19:dd:d9:dd:c25:c25b:d00a:a4a8/1282c19:dd:d9:dd:c25:c25b:d00a:a4a8
1702c19:dd:d9:dd:c25:c25b:d00a:a4a9/1282c19:dd:d9:dd:c25:c25b:d00a:a4a9
1712c19:dd:d9:dd:c25:c25b:d00a:a4aa/1282c19:dd:d9:dd:c25:c25b:d00a:a4aa
1722c19:dd:d9:dd:c25:c25b:d00a:a4ab/1282c19:dd:d9:dd:c25:c25b:d00a:a4ab
1732c19:dd:d9:dd:c25:c25b:d00a:a4ac/1282c19:dd:d9:dd:c25:c25b:d00a:a4ac
1742c19:dd:d9:dd:c25:c25b:d00a:a4ad/1282c19:dd:d9:dd:c25:c25b:d00a:a4ad
1752c19:dd:d9:dd:c25:c25b:d00a:a4ae/1282c19:dd:d9:dd:c25:c25b:d00a:a4ae
1762c19:dd:d9:dd:c25:c25b:d00a:a4af/1282c19:dd:d9:dd:c25:c25b:d00a:a4af
1772c19:dd:d9:dd:c25:c25b:d00a:a4b0/1282c19:dd:d9:dd:c25:c25b:d00a:a4b0
1782c19:dd:d9:dd:c25:c25b:d00a:a4b1/1282c19:dd:d9:dd:c25:c25b:d00a:a4b1
1792c19:dd:d9:dd:c25:c25b:d00a:a4b2/1282c19:dd:d9:dd:c25:c25b:d00a:a4b2
1802c19:dd:d9:dd:c25:c25b:d00a:a4b3/1282c19:dd:d9:dd:c25:c25b:d00a:a4b3
1812c19:dd:d9:dd:c25:c25b:d00a:a4b4/1282c19:dd:d9:dd:c25:c25b:d00a:a4b4
1822c19:dd:d9:dd:c25:c25b:d00a:a4b5/1282c19:dd:d9:dd:c25:c25b:d00a:a4b5
1832c19:dd:d9:dd:c25:c25b:d00a:a4b6/1282c19:dd:d9:dd:c25:c25b:d00a:a4b6
1842c19:dd:d9:dd:c25:c25b:d00a:a4b7/1282c19:dd:d9:dd:c25:c25b:d00a:a4b7
1852c19:dd:d9:dd:c25:c25b:d00a:a4b8/1282c19:dd:d9:dd:c25:c25b:d00a:a4b8
1862c19:dd:d9:dd:c25:c25b:d00a:a4b9/1282c19:dd:d9:dd:c25:c25b:d00a:a4b9
1872c19:dd:d9:dd:c25:c25b:d00a:a4ba/1282c19:dd:d9:dd:c25:c25b:d00a:a4ba
1882c19:dd:d9:dd:c25:c25b:d00a:a4bb/1282c19:dd:d9:dd:c25:c25b:d00a:a4bb
1892c19:dd:d9:dd:c25:c25b:d00a:a4bc/1282c19:dd:d9:dd:c25:c25b:d00a:a4bc
1902c19:dd:d9:dd:c25:c25b:d00a:a4bd/1282c19:dd:d9:dd:c25:c25b:d00a:a4bd
1912c19:dd:d9:dd:c25:c25b:d00a:a4be/1282c19:dd:d9:dd:c25:c25b:d00a:a4be
1922c19:dd:d9:dd:c25:c25b:d00a:a4bf/1282c19:dd:d9:dd:c25:c25b:d00a:a4bf
1932c19:dd:d9:dd:c25:c25b:d00a:a4c0/1282c19:dd:d9:dd:c25:c25b:d00a:a4c0
1942c19:dd:d9:dd:c25:c25b:d00a:a4c1/1282c19:dd:d9:dd:c25:c25b:d00a:a4c1
1952c19:dd:d9:dd:c25:c25b:d00a:a4c2/1282c19:dd:d9:dd:c25:c25b:d00a:a4c2
1962c19:dd:d9:dd:c25:c25b:d00a:a4c3/1282c19:dd:d9:dd:c25:c25b:d00a:a4c3
1972c19:dd:d9:dd:c25:c25b:d00a:a4c4/1282c19:dd:d9:dd:c25:c25b:d00a:a4c4
1982c19:dd:d9:dd:c25:c25b:d00a:a4c5/1282c19:dd:d9:dd:c25:c25b:d00a:a4c5
1992c19:dd:d9:dd:c25:c25b:d00a:a4c6/1282c19:dd:d9:dd:c25:c25b:d00a:a4c6
2002c19:dd:d9:dd:c25:c25b:d00a:a4c7/1282c19:dd:d9:dd:c25:c25b:d00a:a4c7
2012c19:dd:d9:dd:c25:c25b:d00a:a4c8/1282c19:dd:d9:dd:c25:c25b:d00a:a4c8
2022c19:dd:d9:dd:c25:c25b:d00a:a4c9/1282c19:dd:d9:dd:c25:c25b:d00a:a4c9
2032c19:dd:d9:dd:c25:c25b:d00a:a4ca/1282c19:dd:d9:dd:c25:c25b:d00a:a4ca
2042c19:dd:d9:dd:c25:c25b:d00a:a4cb/1282c19:dd:d9:dd:c25:c25b:d00a:a4cb
2052c19:dd:d9:dd:c25:c25b:d00a:a4cc/1282c19:dd:d9:dd:c25:c25b:d00a:a4cc
2062c19:dd:d9:dd:c25:c25b:d00a:a4cd/1282c19:dd:d9:dd:c25:c25b:d00a:a4cd
2072c19:dd:d9:dd:c25:c25b:d00a:a4ce/1282c19:dd:d9:dd:c25:c25b:d00a:a4ce
2082c19:dd:d9:dd:c25:c25b:d00a:a4cf/1282c19:dd:d9:dd:c25:c25b:d00a:a4cf
2092c19:dd:d9:dd:c25:c25b:d00a:a4d0/1282c19:dd:d9:dd:c25:c25b:d00a:a4d0
2102c19:dd:d9:dd:c25:c25b:d00a:a4d1/1282c19:dd:d9:dd:c25:c25b:d00a:a4d1
2112c19:dd:d9:dd:c25:c25b:d00a:a4d2/1282c19:dd:d9:dd:c25:c25b:d00a:a4d2
2122c19:dd:d9:dd:c25:c25b:d00a:a4d3/1282c19:dd:d9:dd:c25:c25b:d00a:a4d3
2132c19:dd:d9:dd:c25:c25b:d00a:a4d4/1282c19:dd:d9:dd:c25:c25b:d00a:a4d4
2142c19:dd:d9:dd:c25:c25b:d00a:a4d5/1282c19:dd:d9:dd:c25:c25b:d00a:a4d5
2152c19:dd:d9:dd:c25:c25b:d00a:a4d6/1282c19:dd:d9:dd:c25:c25b:d00a:a4d6
2162c19:dd:d9:dd:c25:c25b:d00a:a4d7/1282c19:dd:d9:dd:c25:c25b:d00a:a4d7
2172c19:dd:d9:dd:c25:c25b:d00a:a4d8/1282c19:dd:d9:dd:c25:c25b:d00a:a4d8
2182c19:dd:d9:dd:c25:c25b:d00a:a4d9/1282c19:dd:d9:dd:c25:c25b:d00a:a4d9
2192c19:dd:d9:dd:c25:c25b:d00a:a4da/1282c19:dd:d9:dd:c25:c25b:d00a:a4da
2202c19:dd:d9:dd:c25:c25b:d00a:a4db/1282c19:dd:d9:dd:c25:c25b:d00a:a4db
2212c19:dd:d9:dd:c25:c25b:d00a:a4dc/1282c19:dd:d9:dd:c25:c25b:d00a:a4dc
2222c19:dd:d9:dd:c25:c25b:d00a:a4dd/1282c19:dd:d9:dd:c25:c25b:d00a:a4dd
2232c19:dd:d9:dd:c25:c25b:d00a:a4de/1282c19:dd:d9:dd:c25:c25b:d00a:a4de
2242c19:dd:d9:dd:c25:c25b:d00a:a4df/1282c19:dd:d9:dd:c25:c25b:d00a:a4df
2252c19:dd:d9:dd:c25:c25b:d00a:a4e0/1282c19:dd:d9:dd:c25:c25b:d00a:a4e0
2262c19:dd:d9:dd:c25:c25b:d00a:a4e1/1282c19:dd:d9:dd:c25:c25b:d00a:a4e1
2272c19:dd:d9:dd:c25:c25b:d00a:a4e2/1282c19:dd:d9:dd:c25:c25b:d00a:a4e2
2282c19:dd:d9:dd:c25:c25b:d00a:a4e3/1282c19:dd:d9:dd:c25:c25b:d00a:a4e3
2292c19:dd:d9:dd:c25:c25b:d00a:a4e4/1282c19:dd:d9:dd:c25:c25b:d00a:a4e4
2302c19:dd:d9:dd:c25:c25b:d00a:a4e5/1282c19:dd:d9:dd:c25:c25b:d00a:a4e5
2312c19:dd:d9:dd:c25:c25b:d00a:a4e6/1282c19:dd:d9:dd:c25:c25b:d00a:a4e6
2322c19:dd:d9:dd:c25:c25b:d00a:a4e7/1282c19:dd:d9:dd:c25:c25b:d00a:a4e7
2332c19:dd:d9:dd:c25:c25b:d00a:a4e8/1282c19:dd:d9:dd:c25:c25b:d00a:a4e8
2342c19:dd:d9:dd:c25:c25b:d00a:a4e9/1282c19:dd:d9:dd:c25:c25b:d00a:a4e9
2352c19:dd:d9:dd:c25:c25b:d00a:a4ea/1282c19:dd:d9:dd:c25:c25b:d00a:a4ea
2362c19:dd:d9:dd:c25:c25b:d00a:a4eb/1282c19:dd:d9:dd:c25:c25b:d00a:a4eb
2372c19:dd:d9:dd:c25:c25b:d00a:a4ec/1282c19:dd:d9:dd:c25:c25b:d00a:a4ec
2382c19:dd:d9:dd:c25:c25b:d00a:a4ed/1282c19:dd:d9:dd:c25:c25b:d00a:a4ed
2392c19:dd:d9:dd:c25:c25b:d00a:a4ee/1282c19:dd:d9:dd:c25:c25b:d00a:a4ee
2402c19:dd:d9:dd:c25:c25b:d00a:a4ef/1282c19:dd:d9:dd:c25:c25b:d00a:a4ef
2412c19:dd:d9:dd:c25:c25b:d00a:a4f0/1282c19:dd:d9:dd:c25:c25b:d00a:a4f0
2422c19:dd:d9:dd:c25:c25b:d00a:a4f1/1282c19:dd:d9:dd:c25:c25b:d00a:a4f1
2432c19:dd:d9:dd:c25:c25b:d00a:a4f2/1282c19:dd:d9:dd:c25:c25b:d00a:a4f2
2442c19:dd:d9:dd:c25:c25b:d00a:a4f3/1282c19:dd:d9:dd:c25:c25b:d00a:a4f3
2452c19:dd:d9:dd:c25:c25b:d00a:a4f4/1282c19:dd:d9:dd:c25:c25b:d00a:a4f4
2462c19:dd:d9:dd:c25:c25b:d00a:a4f5/1282c19:dd:d9:dd:c25:c25b:d00a:a4f5
2472c19:dd:d9:dd:c25:c25b:d00a:a4f6/1282c19:dd:d9:dd:c25:c25b:d00a:a4f6
2482c19:dd:d9:dd:c25:c25b:d00a:a4f7/1282c19:dd:d9:dd:c25:c25b:d00a:a4f7
2492c19:dd:d9:dd:c25:c25b:d00a:a4f8/1282c19:dd:d9:dd:c25:c25b:d00a:a4f8
2502c19:dd:d9:dd:c25:c25b:d00a:a4f9/1282c19:dd:d9:dd:c25:c25b:d00a:a4f9
2512c19:dd:d9:dd:c25:c25b:d00a:a4fa/1282c19:dd:d9:dd:c25:c25b:d00a:a4fa
2522c19:dd:d9:dd:c25:c25b:d00a:a4fb/1282c19:dd:d9:dd:c25:c25b:d00a:a4fb
2532c19:dd:d9:dd:c25:c25b:d00a:a4fc/1282c19:dd:d9:dd:c25:c25b:d00a:a4fc
2542c19:dd:d9:dd:c25:c25b:d00a:a4fd/1282c19:dd:d9:dd:c25:c25b:d00a:a4fd
2552c19:dd:d9:dd:c25:c25b:d00a:a4fe/1282c19:dd:d9:dd:c25:c25b:d00a:a4fe
2562c19:dd:d9:dd:c25:c25b:d00a:a4ff/1282c19:dd:d9:dd:c25:c25b:d00a:a4ff

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.