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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:c00a:e400/120
First address
2c19:dd:d9:dd:c25:c25:c00a:e400
Last address
2c19:dd:d9:dd:c25:c25:c00a:e4ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:c00a:e400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.e.a.0.0.c.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:c00a:e400/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:c00a:e400/1282c19:dd:d9:dd:c25:c25:c00a:e400
22c19:dd:d9:dd:c25:c25:c00a:e401/1282c19:dd:d9:dd:c25:c25:c00a:e401
32c19:dd:d9:dd:c25:c25:c00a:e402/1282c19:dd:d9:dd:c25:c25:c00a:e402
42c19:dd:d9:dd:c25:c25:c00a:e403/1282c19:dd:d9:dd:c25:c25:c00a:e403
52c19:dd:d9:dd:c25:c25:c00a:e404/1282c19:dd:d9:dd:c25:c25:c00a:e404
62c19:dd:d9:dd:c25:c25:c00a:e405/1282c19:dd:d9:dd:c25:c25:c00a:e405
72c19:dd:d9:dd:c25:c25:c00a:e406/1282c19:dd:d9:dd:c25:c25:c00a:e406
82c19:dd:d9:dd:c25:c25:c00a:e407/1282c19:dd:d9:dd:c25:c25:c00a:e407
92c19:dd:d9:dd:c25:c25:c00a:e408/1282c19:dd:d9:dd:c25:c25:c00a:e408
102c19:dd:d9:dd:c25:c25:c00a:e409/1282c19:dd:d9:dd:c25:c25:c00a:e409
112c19:dd:d9:dd:c25:c25:c00a:e40a/1282c19:dd:d9:dd:c25:c25:c00a:e40a
122c19:dd:d9:dd:c25:c25:c00a:e40b/1282c19:dd:d9:dd:c25:c25:c00a:e40b
132c19:dd:d9:dd:c25:c25:c00a:e40c/1282c19:dd:d9:dd:c25:c25:c00a:e40c
142c19:dd:d9:dd:c25:c25:c00a:e40d/1282c19:dd:d9:dd:c25:c25:c00a:e40d
152c19:dd:d9:dd:c25:c25:c00a:e40e/1282c19:dd:d9:dd:c25:c25:c00a:e40e
162c19:dd:d9:dd:c25:c25:c00a:e40f/1282c19:dd:d9:dd:c25:c25:c00a:e40f
172c19:dd:d9:dd:c25:c25:c00a:e410/1282c19:dd:d9:dd:c25:c25:c00a:e410
182c19:dd:d9:dd:c25:c25:c00a:e411/1282c19:dd:d9:dd:c25:c25:c00a:e411
192c19:dd:d9:dd:c25:c25:c00a:e412/1282c19:dd:d9:dd:c25:c25:c00a:e412
202c19:dd:d9:dd:c25:c25:c00a:e413/1282c19:dd:d9:dd:c25:c25:c00a:e413
212c19:dd:d9:dd:c25:c25:c00a:e414/1282c19:dd:d9:dd:c25:c25:c00a:e414
222c19:dd:d9:dd:c25:c25:c00a:e415/1282c19:dd:d9:dd:c25:c25:c00a:e415
232c19:dd:d9:dd:c25:c25:c00a:e416/1282c19:dd:d9:dd:c25:c25:c00a:e416
242c19:dd:d9:dd:c25:c25:c00a:e417/1282c19:dd:d9:dd:c25:c25:c00a:e417
252c19:dd:d9:dd:c25:c25:c00a:e418/1282c19:dd:d9:dd:c25:c25:c00a:e418
262c19:dd:d9:dd:c25:c25:c00a:e419/1282c19:dd:d9:dd:c25:c25:c00a:e419
272c19:dd:d9:dd:c25:c25:c00a:e41a/1282c19:dd:d9:dd:c25:c25:c00a:e41a
282c19:dd:d9:dd:c25:c25:c00a:e41b/1282c19:dd:d9:dd:c25:c25:c00a:e41b
292c19:dd:d9:dd:c25:c25:c00a:e41c/1282c19:dd:d9:dd:c25:c25:c00a:e41c
302c19:dd:d9:dd:c25:c25:c00a:e41d/1282c19:dd:d9:dd:c25:c25:c00a:e41d
312c19:dd:d9:dd:c25:c25:c00a:e41e/1282c19:dd:d9:dd:c25:c25:c00a:e41e
322c19:dd:d9:dd:c25:c25:c00a:e41f/1282c19:dd:d9:dd:c25:c25:c00a:e41f
332c19:dd:d9:dd:c25:c25:c00a:e420/1282c19:dd:d9:dd:c25:c25:c00a:e420
342c19:dd:d9:dd:c25:c25:c00a:e421/1282c19:dd:d9:dd:c25:c25:c00a:e421
352c19:dd:d9:dd:c25:c25:c00a:e422/1282c19:dd:d9:dd:c25:c25:c00a:e422
362c19:dd:d9:dd:c25:c25:c00a:e423/1282c19:dd:d9:dd:c25:c25:c00a:e423
372c19:dd:d9:dd:c25:c25:c00a:e424/1282c19:dd:d9:dd:c25:c25:c00a:e424
382c19:dd:d9:dd:c25:c25:c00a:e425/1282c19:dd:d9:dd:c25:c25:c00a:e425
392c19:dd:d9:dd:c25:c25:c00a:e426/1282c19:dd:d9:dd:c25:c25:c00a:e426
402c19:dd:d9:dd:c25:c25:c00a:e427/1282c19:dd:d9:dd:c25:c25:c00a:e427
412c19:dd:d9:dd:c25:c25:c00a:e428/1282c19:dd:d9:dd:c25:c25:c00a:e428
422c19:dd:d9:dd:c25:c25:c00a:e429/1282c19:dd:d9:dd:c25:c25:c00a:e429
432c19:dd:d9:dd:c25:c25:c00a:e42a/1282c19:dd:d9:dd:c25:c25:c00a:e42a
442c19:dd:d9:dd:c25:c25:c00a:e42b/1282c19:dd:d9:dd:c25:c25:c00a:e42b
452c19:dd:d9:dd:c25:c25:c00a:e42c/1282c19:dd:d9:dd:c25:c25:c00a:e42c
462c19:dd:d9:dd:c25:c25:c00a:e42d/1282c19:dd:d9:dd:c25:c25:c00a:e42d
472c19:dd:d9:dd:c25:c25:c00a:e42e/1282c19:dd:d9:dd:c25:c25:c00a:e42e
482c19:dd:d9:dd:c25:c25:c00a:e42f/1282c19:dd:d9:dd:c25:c25:c00a:e42f
492c19:dd:d9:dd:c25:c25:c00a:e430/1282c19:dd:d9:dd:c25:c25:c00a:e430
502c19:dd:d9:dd:c25:c25:c00a:e431/1282c19:dd:d9:dd:c25:c25:c00a:e431
512c19:dd:d9:dd:c25:c25:c00a:e432/1282c19:dd:d9:dd:c25:c25:c00a:e432
522c19:dd:d9:dd:c25:c25:c00a:e433/1282c19:dd:d9:dd:c25:c25:c00a:e433
532c19:dd:d9:dd:c25:c25:c00a:e434/1282c19:dd:d9:dd:c25:c25:c00a:e434
542c19:dd:d9:dd:c25:c25:c00a:e435/1282c19:dd:d9:dd:c25:c25:c00a:e435
552c19:dd:d9:dd:c25:c25:c00a:e436/1282c19:dd:d9:dd:c25:c25:c00a:e436
562c19:dd:d9:dd:c25:c25:c00a:e437/1282c19:dd:d9:dd:c25:c25:c00a:e437
572c19:dd:d9:dd:c25:c25:c00a:e438/1282c19:dd:d9:dd:c25:c25:c00a:e438
582c19:dd:d9:dd:c25:c25:c00a:e439/1282c19:dd:d9:dd:c25:c25:c00a:e439
592c19:dd:d9:dd:c25:c25:c00a:e43a/1282c19:dd:d9:dd:c25:c25:c00a:e43a
602c19:dd:d9:dd:c25:c25:c00a:e43b/1282c19:dd:d9:dd:c25:c25:c00a:e43b
612c19:dd:d9:dd:c25:c25:c00a:e43c/1282c19:dd:d9:dd:c25:c25:c00a:e43c
622c19:dd:d9:dd:c25:c25:c00a:e43d/1282c19:dd:d9:dd:c25:c25:c00a:e43d
632c19:dd:d9:dd:c25:c25:c00a:e43e/1282c19:dd:d9:dd:c25:c25:c00a:e43e
642c19:dd:d9:dd:c25:c25:c00a:e43f/1282c19:dd:d9:dd:c25:c25:c00a:e43f
652c19:dd:d9:dd:c25:c25:c00a:e440/1282c19:dd:d9:dd:c25:c25:c00a:e440
662c19:dd:d9:dd:c25:c25:c00a:e441/1282c19:dd:d9:dd:c25:c25:c00a:e441
672c19:dd:d9:dd:c25:c25:c00a:e442/1282c19:dd:d9:dd:c25:c25:c00a:e442
682c19:dd:d9:dd:c25:c25:c00a:e443/1282c19:dd:d9:dd:c25:c25:c00a:e443
692c19:dd:d9:dd:c25:c25:c00a:e444/1282c19:dd:d9:dd:c25:c25:c00a:e444
702c19:dd:d9:dd:c25:c25:c00a:e445/1282c19:dd:d9:dd:c25:c25:c00a:e445
712c19:dd:d9:dd:c25:c25:c00a:e446/1282c19:dd:d9:dd:c25:c25:c00a:e446
722c19:dd:d9:dd:c25:c25:c00a:e447/1282c19:dd:d9:dd:c25:c25:c00a:e447
732c19:dd:d9:dd:c25:c25:c00a:e448/1282c19:dd:d9:dd:c25:c25:c00a:e448
742c19:dd:d9:dd:c25:c25:c00a:e449/1282c19:dd:d9:dd:c25:c25:c00a:e449
752c19:dd:d9:dd:c25:c25:c00a:e44a/1282c19:dd:d9:dd:c25:c25:c00a:e44a
762c19:dd:d9:dd:c25:c25:c00a:e44b/1282c19:dd:d9:dd:c25:c25:c00a:e44b
772c19:dd:d9:dd:c25:c25:c00a:e44c/1282c19:dd:d9:dd:c25:c25:c00a:e44c
782c19:dd:d9:dd:c25:c25:c00a:e44d/1282c19:dd:d9:dd:c25:c25:c00a:e44d
792c19:dd:d9:dd:c25:c25:c00a:e44e/1282c19:dd:d9:dd:c25:c25:c00a:e44e
802c19:dd:d9:dd:c25:c25:c00a:e44f/1282c19:dd:d9:dd:c25:c25:c00a:e44f
812c19:dd:d9:dd:c25:c25:c00a:e450/1282c19:dd:d9:dd:c25:c25:c00a:e450
822c19:dd:d9:dd:c25:c25:c00a:e451/1282c19:dd:d9:dd:c25:c25:c00a:e451
832c19:dd:d9:dd:c25:c25:c00a:e452/1282c19:dd:d9:dd:c25:c25:c00a:e452
842c19:dd:d9:dd:c25:c25:c00a:e453/1282c19:dd:d9:dd:c25:c25:c00a:e453
852c19:dd:d9:dd:c25:c25:c00a:e454/1282c19:dd:d9:dd:c25:c25:c00a:e454
862c19:dd:d9:dd:c25:c25:c00a:e455/1282c19:dd:d9:dd:c25:c25:c00a:e455
872c19:dd:d9:dd:c25:c25:c00a:e456/1282c19:dd:d9:dd:c25:c25:c00a:e456
882c19:dd:d9:dd:c25:c25:c00a:e457/1282c19:dd:d9:dd:c25:c25:c00a:e457
892c19:dd:d9:dd:c25:c25:c00a:e458/1282c19:dd:d9:dd:c25:c25:c00a:e458
902c19:dd:d9:dd:c25:c25:c00a:e459/1282c19:dd:d9:dd:c25:c25:c00a:e459
912c19:dd:d9:dd:c25:c25:c00a:e45a/1282c19:dd:d9:dd:c25:c25:c00a:e45a
922c19:dd:d9:dd:c25:c25:c00a:e45b/1282c19:dd:d9:dd:c25:c25:c00a:e45b
932c19:dd:d9:dd:c25:c25:c00a:e45c/1282c19:dd:d9:dd:c25:c25:c00a:e45c
942c19:dd:d9:dd:c25:c25:c00a:e45d/1282c19:dd:d9:dd:c25:c25:c00a:e45d
952c19:dd:d9:dd:c25:c25:c00a:e45e/1282c19:dd:d9:dd:c25:c25:c00a:e45e
962c19:dd:d9:dd:c25:c25:c00a:e45f/1282c19:dd:d9:dd:c25:c25:c00a:e45f
972c19:dd:d9:dd:c25:c25:c00a:e460/1282c19:dd:d9:dd:c25:c25:c00a:e460
982c19:dd:d9:dd:c25:c25:c00a:e461/1282c19:dd:d9:dd:c25:c25:c00a:e461
992c19:dd:d9:dd:c25:c25:c00a:e462/1282c19:dd:d9:dd:c25:c25:c00a:e462
1002c19:dd:d9:dd:c25:c25:c00a:e463/1282c19:dd:d9:dd:c25:c25:c00a:e463
1012c19:dd:d9:dd:c25:c25:c00a:e464/1282c19:dd:d9:dd:c25:c25:c00a:e464
1022c19:dd:d9:dd:c25:c25:c00a:e465/1282c19:dd:d9:dd:c25:c25:c00a:e465
1032c19:dd:d9:dd:c25:c25:c00a:e466/1282c19:dd:d9:dd:c25:c25:c00a:e466
1042c19:dd:d9:dd:c25:c25:c00a:e467/1282c19:dd:d9:dd:c25:c25:c00a:e467
1052c19:dd:d9:dd:c25:c25:c00a:e468/1282c19:dd:d9:dd:c25:c25:c00a:e468
1062c19:dd:d9:dd:c25:c25:c00a:e469/1282c19:dd:d9:dd:c25:c25:c00a:e469
1072c19:dd:d9:dd:c25:c25:c00a:e46a/1282c19:dd:d9:dd:c25:c25:c00a:e46a
1082c19:dd:d9:dd:c25:c25:c00a:e46b/1282c19:dd:d9:dd:c25:c25:c00a:e46b
1092c19:dd:d9:dd:c25:c25:c00a:e46c/1282c19:dd:d9:dd:c25:c25:c00a:e46c
1102c19:dd:d9:dd:c25:c25:c00a:e46d/1282c19:dd:d9:dd:c25:c25:c00a:e46d
1112c19:dd:d9:dd:c25:c25:c00a:e46e/1282c19:dd:d9:dd:c25:c25:c00a:e46e
1122c19:dd:d9:dd:c25:c25:c00a:e46f/1282c19:dd:d9:dd:c25:c25:c00a:e46f
1132c19:dd:d9:dd:c25:c25:c00a:e470/1282c19:dd:d9:dd:c25:c25:c00a:e470
1142c19:dd:d9:dd:c25:c25:c00a:e471/1282c19:dd:d9:dd:c25:c25:c00a:e471
1152c19:dd:d9:dd:c25:c25:c00a:e472/1282c19:dd:d9:dd:c25:c25:c00a:e472
1162c19:dd:d9:dd:c25:c25:c00a:e473/1282c19:dd:d9:dd:c25:c25:c00a:e473
1172c19:dd:d9:dd:c25:c25:c00a:e474/1282c19:dd:d9:dd:c25:c25:c00a:e474
1182c19:dd:d9:dd:c25:c25:c00a:e475/1282c19:dd:d9:dd:c25:c25:c00a:e475
1192c19:dd:d9:dd:c25:c25:c00a:e476/1282c19:dd:d9:dd:c25:c25:c00a:e476
1202c19:dd:d9:dd:c25:c25:c00a:e477/1282c19:dd:d9:dd:c25:c25:c00a:e477
1212c19:dd:d9:dd:c25:c25:c00a:e478/1282c19:dd:d9:dd:c25:c25:c00a:e478
1222c19:dd:d9:dd:c25:c25:c00a:e479/1282c19:dd:d9:dd:c25:c25:c00a:e479
1232c19:dd:d9:dd:c25:c25:c00a:e47a/1282c19:dd:d9:dd:c25:c25:c00a:e47a
1242c19:dd:d9:dd:c25:c25:c00a:e47b/1282c19:dd:d9:dd:c25:c25:c00a:e47b
1252c19:dd:d9:dd:c25:c25:c00a:e47c/1282c19:dd:d9:dd:c25:c25:c00a:e47c
1262c19:dd:d9:dd:c25:c25:c00a:e47d/1282c19:dd:d9:dd:c25:c25:c00a:e47d
1272c19:dd:d9:dd:c25:c25:c00a:e47e/1282c19:dd:d9:dd:c25:c25:c00a:e47e
1282c19:dd:d9:dd:c25:c25:c00a:e47f/1282c19:dd:d9:dd:c25:c25:c00a:e47f
1292c19:dd:d9:dd:c25:c25:c00a:e480/1282c19:dd:d9:dd:c25:c25:c00a:e480
1302c19:dd:d9:dd:c25:c25:c00a:e481/1282c19:dd:d9:dd:c25:c25:c00a:e481
1312c19:dd:d9:dd:c25:c25:c00a:e482/1282c19:dd:d9:dd:c25:c25:c00a:e482
1322c19:dd:d9:dd:c25:c25:c00a:e483/1282c19:dd:d9:dd:c25:c25:c00a:e483
1332c19:dd:d9:dd:c25:c25:c00a:e484/1282c19:dd:d9:dd:c25:c25:c00a:e484
1342c19:dd:d9:dd:c25:c25:c00a:e485/1282c19:dd:d9:dd:c25:c25:c00a:e485
1352c19:dd:d9:dd:c25:c25:c00a:e486/1282c19:dd:d9:dd:c25:c25:c00a:e486
1362c19:dd:d9:dd:c25:c25:c00a:e487/1282c19:dd:d9:dd:c25:c25:c00a:e487
1372c19:dd:d9:dd:c25:c25:c00a:e488/1282c19:dd:d9:dd:c25:c25:c00a:e488
1382c19:dd:d9:dd:c25:c25:c00a:e489/1282c19:dd:d9:dd:c25:c25:c00a:e489
1392c19:dd:d9:dd:c25:c25:c00a:e48a/1282c19:dd:d9:dd:c25:c25:c00a:e48a
1402c19:dd:d9:dd:c25:c25:c00a:e48b/1282c19:dd:d9:dd:c25:c25:c00a:e48b
1412c19:dd:d9:dd:c25:c25:c00a:e48c/1282c19:dd:d9:dd:c25:c25:c00a:e48c
1422c19:dd:d9:dd:c25:c25:c00a:e48d/1282c19:dd:d9:dd:c25:c25:c00a:e48d
1432c19:dd:d9:dd:c25:c25:c00a:e48e/1282c19:dd:d9:dd:c25:c25:c00a:e48e
1442c19:dd:d9:dd:c25:c25:c00a:e48f/1282c19:dd:d9:dd:c25:c25:c00a:e48f
1452c19:dd:d9:dd:c25:c25:c00a:e490/1282c19:dd:d9:dd:c25:c25:c00a:e490
1462c19:dd:d9:dd:c25:c25:c00a:e491/1282c19:dd:d9:dd:c25:c25:c00a:e491
1472c19:dd:d9:dd:c25:c25:c00a:e492/1282c19:dd:d9:dd:c25:c25:c00a:e492
1482c19:dd:d9:dd:c25:c25:c00a:e493/1282c19:dd:d9:dd:c25:c25:c00a:e493
1492c19:dd:d9:dd:c25:c25:c00a:e494/1282c19:dd:d9:dd:c25:c25:c00a:e494
1502c19:dd:d9:dd:c25:c25:c00a:e495/1282c19:dd:d9:dd:c25:c25:c00a:e495
1512c19:dd:d9:dd:c25:c25:c00a:e496/1282c19:dd:d9:dd:c25:c25:c00a:e496
1522c19:dd:d9:dd:c25:c25:c00a:e497/1282c19:dd:d9:dd:c25:c25:c00a:e497
1532c19:dd:d9:dd:c25:c25:c00a:e498/1282c19:dd:d9:dd:c25:c25:c00a:e498
1542c19:dd:d9:dd:c25:c25:c00a:e499/1282c19:dd:d9:dd:c25:c25:c00a:e499
1552c19:dd:d9:dd:c25:c25:c00a:e49a/1282c19:dd:d9:dd:c25:c25:c00a:e49a
1562c19:dd:d9:dd:c25:c25:c00a:e49b/1282c19:dd:d9:dd:c25:c25:c00a:e49b
1572c19:dd:d9:dd:c25:c25:c00a:e49c/1282c19:dd:d9:dd:c25:c25:c00a:e49c
1582c19:dd:d9:dd:c25:c25:c00a:e49d/1282c19:dd:d9:dd:c25:c25:c00a:e49d
1592c19:dd:d9:dd:c25:c25:c00a:e49e/1282c19:dd:d9:dd:c25:c25:c00a:e49e
1602c19:dd:d9:dd:c25:c25:c00a:e49f/1282c19:dd:d9:dd:c25:c25:c00a:e49f
1612c19:dd:d9:dd:c25:c25:c00a:e4a0/1282c19:dd:d9:dd:c25:c25:c00a:e4a0
1622c19:dd:d9:dd:c25:c25:c00a:e4a1/1282c19:dd:d9:dd:c25:c25:c00a:e4a1
1632c19:dd:d9:dd:c25:c25:c00a:e4a2/1282c19:dd:d9:dd:c25:c25:c00a:e4a2
1642c19:dd:d9:dd:c25:c25:c00a:e4a3/1282c19:dd:d9:dd:c25:c25:c00a:e4a3
1652c19:dd:d9:dd:c25:c25:c00a:e4a4/1282c19:dd:d9:dd:c25:c25:c00a:e4a4
1662c19:dd:d9:dd:c25:c25:c00a:e4a5/1282c19:dd:d9:dd:c25:c25:c00a:e4a5
1672c19:dd:d9:dd:c25:c25:c00a:e4a6/1282c19:dd:d9:dd:c25:c25:c00a:e4a6
1682c19:dd:d9:dd:c25:c25:c00a:e4a7/1282c19:dd:d9:dd:c25:c25:c00a:e4a7
1692c19:dd:d9:dd:c25:c25:c00a:e4a8/1282c19:dd:d9:dd:c25:c25:c00a:e4a8
1702c19:dd:d9:dd:c25:c25:c00a:e4a9/1282c19:dd:d9:dd:c25:c25:c00a:e4a9
1712c19:dd:d9:dd:c25:c25:c00a:e4aa/1282c19:dd:d9:dd:c25:c25:c00a:e4aa
1722c19:dd:d9:dd:c25:c25:c00a:e4ab/1282c19:dd:d9:dd:c25:c25:c00a:e4ab
1732c19:dd:d9:dd:c25:c25:c00a:e4ac/1282c19:dd:d9:dd:c25:c25:c00a:e4ac
1742c19:dd:d9:dd:c25:c25:c00a:e4ad/1282c19:dd:d9:dd:c25:c25:c00a:e4ad
1752c19:dd:d9:dd:c25:c25:c00a:e4ae/1282c19:dd:d9:dd:c25:c25:c00a:e4ae
1762c19:dd:d9:dd:c25:c25:c00a:e4af/1282c19:dd:d9:dd:c25:c25:c00a:e4af
1772c19:dd:d9:dd:c25:c25:c00a:e4b0/1282c19:dd:d9:dd:c25:c25:c00a:e4b0
1782c19:dd:d9:dd:c25:c25:c00a:e4b1/1282c19:dd:d9:dd:c25:c25:c00a:e4b1
1792c19:dd:d9:dd:c25:c25:c00a:e4b2/1282c19:dd:d9:dd:c25:c25:c00a:e4b2
1802c19:dd:d9:dd:c25:c25:c00a:e4b3/1282c19:dd:d9:dd:c25:c25:c00a:e4b3
1812c19:dd:d9:dd:c25:c25:c00a:e4b4/1282c19:dd:d9:dd:c25:c25:c00a:e4b4
1822c19:dd:d9:dd:c25:c25:c00a:e4b5/1282c19:dd:d9:dd:c25:c25:c00a:e4b5
1832c19:dd:d9:dd:c25:c25:c00a:e4b6/1282c19:dd:d9:dd:c25:c25:c00a:e4b6
1842c19:dd:d9:dd:c25:c25:c00a:e4b7/1282c19:dd:d9:dd:c25:c25:c00a:e4b7
1852c19:dd:d9:dd:c25:c25:c00a:e4b8/1282c19:dd:d9:dd:c25:c25:c00a:e4b8
1862c19:dd:d9:dd:c25:c25:c00a:e4b9/1282c19:dd:d9:dd:c25:c25:c00a:e4b9
1872c19:dd:d9:dd:c25:c25:c00a:e4ba/1282c19:dd:d9:dd:c25:c25:c00a:e4ba
1882c19:dd:d9:dd:c25:c25:c00a:e4bb/1282c19:dd:d9:dd:c25:c25:c00a:e4bb
1892c19:dd:d9:dd:c25:c25:c00a:e4bc/1282c19:dd:d9:dd:c25:c25:c00a:e4bc
1902c19:dd:d9:dd:c25:c25:c00a:e4bd/1282c19:dd:d9:dd:c25:c25:c00a:e4bd
1912c19:dd:d9:dd:c25:c25:c00a:e4be/1282c19:dd:d9:dd:c25:c25:c00a:e4be
1922c19:dd:d9:dd:c25:c25:c00a:e4bf/1282c19:dd:d9:dd:c25:c25:c00a:e4bf
1932c19:dd:d9:dd:c25:c25:c00a:e4c0/1282c19:dd:d9:dd:c25:c25:c00a:e4c0
1942c19:dd:d9:dd:c25:c25:c00a:e4c1/1282c19:dd:d9:dd:c25:c25:c00a:e4c1
1952c19:dd:d9:dd:c25:c25:c00a:e4c2/1282c19:dd:d9:dd:c25:c25:c00a:e4c2
1962c19:dd:d9:dd:c25:c25:c00a:e4c3/1282c19:dd:d9:dd:c25:c25:c00a:e4c3
1972c19:dd:d9:dd:c25:c25:c00a:e4c4/1282c19:dd:d9:dd:c25:c25:c00a:e4c4
1982c19:dd:d9:dd:c25:c25:c00a:e4c5/1282c19:dd:d9:dd:c25:c25:c00a:e4c5
1992c19:dd:d9:dd:c25:c25:c00a:e4c6/1282c19:dd:d9:dd:c25:c25:c00a:e4c6
2002c19:dd:d9:dd:c25:c25:c00a:e4c7/1282c19:dd:d9:dd:c25:c25:c00a:e4c7
2012c19:dd:d9:dd:c25:c25:c00a:e4c8/1282c19:dd:d9:dd:c25:c25:c00a:e4c8
2022c19:dd:d9:dd:c25:c25:c00a:e4c9/1282c19:dd:d9:dd:c25:c25:c00a:e4c9
2032c19:dd:d9:dd:c25:c25:c00a:e4ca/1282c19:dd:d9:dd:c25:c25:c00a:e4ca
2042c19:dd:d9:dd:c25:c25:c00a:e4cb/1282c19:dd:d9:dd:c25:c25:c00a:e4cb
2052c19:dd:d9:dd:c25:c25:c00a:e4cc/1282c19:dd:d9:dd:c25:c25:c00a:e4cc
2062c19:dd:d9:dd:c25:c25:c00a:e4cd/1282c19:dd:d9:dd:c25:c25:c00a:e4cd
2072c19:dd:d9:dd:c25:c25:c00a:e4ce/1282c19:dd:d9:dd:c25:c25:c00a:e4ce
2082c19:dd:d9:dd:c25:c25:c00a:e4cf/1282c19:dd:d9:dd:c25:c25:c00a:e4cf
2092c19:dd:d9:dd:c25:c25:c00a:e4d0/1282c19:dd:d9:dd:c25:c25:c00a:e4d0
2102c19:dd:d9:dd:c25:c25:c00a:e4d1/1282c19:dd:d9:dd:c25:c25:c00a:e4d1
2112c19:dd:d9:dd:c25:c25:c00a:e4d2/1282c19:dd:d9:dd:c25:c25:c00a:e4d2
2122c19:dd:d9:dd:c25:c25:c00a:e4d3/1282c19:dd:d9:dd:c25:c25:c00a:e4d3
2132c19:dd:d9:dd:c25:c25:c00a:e4d4/1282c19:dd:d9:dd:c25:c25:c00a:e4d4
2142c19:dd:d9:dd:c25:c25:c00a:e4d5/1282c19:dd:d9:dd:c25:c25:c00a:e4d5
2152c19:dd:d9:dd:c25:c25:c00a:e4d6/1282c19:dd:d9:dd:c25:c25:c00a:e4d6
2162c19:dd:d9:dd:c25:c25:c00a:e4d7/1282c19:dd:d9:dd:c25:c25:c00a:e4d7
2172c19:dd:d9:dd:c25:c25:c00a:e4d8/1282c19:dd:d9:dd:c25:c25:c00a:e4d8
2182c19:dd:d9:dd:c25:c25:c00a:e4d9/1282c19:dd:d9:dd:c25:c25:c00a:e4d9
2192c19:dd:d9:dd:c25:c25:c00a:e4da/1282c19:dd:d9:dd:c25:c25:c00a:e4da
2202c19:dd:d9:dd:c25:c25:c00a:e4db/1282c19:dd:d9:dd:c25:c25:c00a:e4db
2212c19:dd:d9:dd:c25:c25:c00a:e4dc/1282c19:dd:d9:dd:c25:c25:c00a:e4dc
2222c19:dd:d9:dd:c25:c25:c00a:e4dd/1282c19:dd:d9:dd:c25:c25:c00a:e4dd
2232c19:dd:d9:dd:c25:c25:c00a:e4de/1282c19:dd:d9:dd:c25:c25:c00a:e4de
2242c19:dd:d9:dd:c25:c25:c00a:e4df/1282c19:dd:d9:dd:c25:c25:c00a:e4df
2252c19:dd:d9:dd:c25:c25:c00a:e4e0/1282c19:dd:d9:dd:c25:c25:c00a:e4e0
2262c19:dd:d9:dd:c25:c25:c00a:e4e1/1282c19:dd:d9:dd:c25:c25:c00a:e4e1
2272c19:dd:d9:dd:c25:c25:c00a:e4e2/1282c19:dd:d9:dd:c25:c25:c00a:e4e2
2282c19:dd:d9:dd:c25:c25:c00a:e4e3/1282c19:dd:d9:dd:c25:c25:c00a:e4e3
2292c19:dd:d9:dd:c25:c25:c00a:e4e4/1282c19:dd:d9:dd:c25:c25:c00a:e4e4
2302c19:dd:d9:dd:c25:c25:c00a:e4e5/1282c19:dd:d9:dd:c25:c25:c00a:e4e5
2312c19:dd:d9:dd:c25:c25:c00a:e4e6/1282c19:dd:d9:dd:c25:c25:c00a:e4e6
2322c19:dd:d9:dd:c25:c25:c00a:e4e7/1282c19:dd:d9:dd:c25:c25:c00a:e4e7
2332c19:dd:d9:dd:c25:c25:c00a:e4e8/1282c19:dd:d9:dd:c25:c25:c00a:e4e8
2342c19:dd:d9:dd:c25:c25:c00a:e4e9/1282c19:dd:d9:dd:c25:c25:c00a:e4e9
2352c19:dd:d9:dd:c25:c25:c00a:e4ea/1282c19:dd:d9:dd:c25:c25:c00a:e4ea
2362c19:dd:d9:dd:c25:c25:c00a:e4eb/1282c19:dd:d9:dd:c25:c25:c00a:e4eb
2372c19:dd:d9:dd:c25:c25:c00a:e4ec/1282c19:dd:d9:dd:c25:c25:c00a:e4ec
2382c19:dd:d9:dd:c25:c25:c00a:e4ed/1282c19:dd:d9:dd:c25:c25:c00a:e4ed
2392c19:dd:d9:dd:c25:c25:c00a:e4ee/1282c19:dd:d9:dd:c25:c25:c00a:e4ee
2402c19:dd:d9:dd:c25:c25:c00a:e4ef/1282c19:dd:d9:dd:c25:c25:c00a:e4ef
2412c19:dd:d9:dd:c25:c25:c00a:e4f0/1282c19:dd:d9:dd:c25:c25:c00a:e4f0
2422c19:dd:d9:dd:c25:c25:c00a:e4f1/1282c19:dd:d9:dd:c25:c25:c00a:e4f1
2432c19:dd:d9:dd:c25:c25:c00a:e4f2/1282c19:dd:d9:dd:c25:c25:c00a:e4f2
2442c19:dd:d9:dd:c25:c25:c00a:e4f3/1282c19:dd:d9:dd:c25:c25:c00a:e4f3
2452c19:dd:d9:dd:c25:c25:c00a:e4f4/1282c19:dd:d9:dd:c25:c25:c00a:e4f4
2462c19:dd:d9:dd:c25:c25:c00a:e4f5/1282c19:dd:d9:dd:c25:c25:c00a:e4f5
2472c19:dd:d9:dd:c25:c25:c00a:e4f6/1282c19:dd:d9:dd:c25:c25:c00a:e4f6
2482c19:dd:d9:dd:c25:c25:c00a:e4f7/1282c19:dd:d9:dd:c25:c25:c00a:e4f7
2492c19:dd:d9:dd:c25:c25:c00a:e4f8/1282c19:dd:d9:dd:c25:c25:c00a:e4f8
2502c19:dd:d9:dd:c25:c25:c00a:e4f9/1282c19:dd:d9:dd:c25:c25:c00a:e4f9
2512c19:dd:d9:dd:c25:c25:c00a:e4fa/1282c19:dd:d9:dd:c25:c25:c00a:e4fa
2522c19:dd:d9:dd:c25:c25:c00a:e4fb/1282c19:dd:d9:dd:c25:c25:c00a:e4fb
2532c19:dd:d9:dd:c25:c25:c00a:e4fc/1282c19:dd:d9:dd:c25:c25:c00a:e4fc
2542c19:dd:d9:dd:c25:c25:c00a:e4fd/1282c19:dd:d9:dd:c25:c25:c00a:e4fd
2552c19:dd:d9:dd:c25:c25:c00a:e4fe/1282c19:dd:d9:dd:c25:c25:c00a:e4fe
2562c19:dd:d9:dd:c25:c25:c00a:e4ff/1282c19:dd:d9:dd:c25:c25:c00a:e4ff

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.