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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:c25a:d00a:f400/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:f400
Last address
2c19:dd:d9:dd:c25:c25a:d00a:f4ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:f400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.f.a.0.0.d.a.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:c25a:d00a:f400/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:f400/1282c19:dd:d9:dd:c25:c25a:d00a:f400
22c19:dd:d9:dd:c25:c25a:d00a:f401/1282c19:dd:d9:dd:c25:c25a:d00a:f401
32c19:dd:d9:dd:c25:c25a:d00a:f402/1282c19:dd:d9:dd:c25:c25a:d00a:f402
42c19:dd:d9:dd:c25:c25a:d00a:f403/1282c19:dd:d9:dd:c25:c25a:d00a:f403
52c19:dd:d9:dd:c25:c25a:d00a:f404/1282c19:dd:d9:dd:c25:c25a:d00a:f404
62c19:dd:d9:dd:c25:c25a:d00a:f405/1282c19:dd:d9:dd:c25:c25a:d00a:f405
72c19:dd:d9:dd:c25:c25a:d00a:f406/1282c19:dd:d9:dd:c25:c25a:d00a:f406
82c19:dd:d9:dd:c25:c25a:d00a:f407/1282c19:dd:d9:dd:c25:c25a:d00a:f407
92c19:dd:d9:dd:c25:c25a:d00a:f408/1282c19:dd:d9:dd:c25:c25a:d00a:f408
102c19:dd:d9:dd:c25:c25a:d00a:f409/1282c19:dd:d9:dd:c25:c25a:d00a:f409
112c19:dd:d9:dd:c25:c25a:d00a:f40a/1282c19:dd:d9:dd:c25:c25a:d00a:f40a
122c19:dd:d9:dd:c25:c25a:d00a:f40b/1282c19:dd:d9:dd:c25:c25a:d00a:f40b
132c19:dd:d9:dd:c25:c25a:d00a:f40c/1282c19:dd:d9:dd:c25:c25a:d00a:f40c
142c19:dd:d9:dd:c25:c25a:d00a:f40d/1282c19:dd:d9:dd:c25:c25a:d00a:f40d
152c19:dd:d9:dd:c25:c25a:d00a:f40e/1282c19:dd:d9:dd:c25:c25a:d00a:f40e
162c19:dd:d9:dd:c25:c25a:d00a:f40f/1282c19:dd:d9:dd:c25:c25a:d00a:f40f
172c19:dd:d9:dd:c25:c25a:d00a:f410/1282c19:dd:d9:dd:c25:c25a:d00a:f410
182c19:dd:d9:dd:c25:c25a:d00a:f411/1282c19:dd:d9:dd:c25:c25a:d00a:f411
192c19:dd:d9:dd:c25:c25a:d00a:f412/1282c19:dd:d9:dd:c25:c25a:d00a:f412
202c19:dd:d9:dd:c25:c25a:d00a:f413/1282c19:dd:d9:dd:c25:c25a:d00a:f413
212c19:dd:d9:dd:c25:c25a:d00a:f414/1282c19:dd:d9:dd:c25:c25a:d00a:f414
222c19:dd:d9:dd:c25:c25a:d00a:f415/1282c19:dd:d9:dd:c25:c25a:d00a:f415
232c19:dd:d9:dd:c25:c25a:d00a:f416/1282c19:dd:d9:dd:c25:c25a:d00a:f416
242c19:dd:d9:dd:c25:c25a:d00a:f417/1282c19:dd:d9:dd:c25:c25a:d00a:f417
252c19:dd:d9:dd:c25:c25a:d00a:f418/1282c19:dd:d9:dd:c25:c25a:d00a:f418
262c19:dd:d9:dd:c25:c25a:d00a:f419/1282c19:dd:d9:dd:c25:c25a:d00a:f419
272c19:dd:d9:dd:c25:c25a:d00a:f41a/1282c19:dd:d9:dd:c25:c25a:d00a:f41a
282c19:dd:d9:dd:c25:c25a:d00a:f41b/1282c19:dd:d9:dd:c25:c25a:d00a:f41b
292c19:dd:d9:dd:c25:c25a:d00a:f41c/1282c19:dd:d9:dd:c25:c25a:d00a:f41c
302c19:dd:d9:dd:c25:c25a:d00a:f41d/1282c19:dd:d9:dd:c25:c25a:d00a:f41d
312c19:dd:d9:dd:c25:c25a:d00a:f41e/1282c19:dd:d9:dd:c25:c25a:d00a:f41e
322c19:dd:d9:dd:c25:c25a:d00a:f41f/1282c19:dd:d9:dd:c25:c25a:d00a:f41f
332c19:dd:d9:dd:c25:c25a:d00a:f420/1282c19:dd:d9:dd:c25:c25a:d00a:f420
342c19:dd:d9:dd:c25:c25a:d00a:f421/1282c19:dd:d9:dd:c25:c25a:d00a:f421
352c19:dd:d9:dd:c25:c25a:d00a:f422/1282c19:dd:d9:dd:c25:c25a:d00a:f422
362c19:dd:d9:dd:c25:c25a:d00a:f423/1282c19:dd:d9:dd:c25:c25a:d00a:f423
372c19:dd:d9:dd:c25:c25a:d00a:f424/1282c19:dd:d9:dd:c25:c25a:d00a:f424
382c19:dd:d9:dd:c25:c25a:d00a:f425/1282c19:dd:d9:dd:c25:c25a:d00a:f425
392c19:dd:d9:dd:c25:c25a:d00a:f426/1282c19:dd:d9:dd:c25:c25a:d00a:f426
402c19:dd:d9:dd:c25:c25a:d00a:f427/1282c19:dd:d9:dd:c25:c25a:d00a:f427
412c19:dd:d9:dd:c25:c25a:d00a:f428/1282c19:dd:d9:dd:c25:c25a:d00a:f428
422c19:dd:d9:dd:c25:c25a:d00a:f429/1282c19:dd:d9:dd:c25:c25a:d00a:f429
432c19:dd:d9:dd:c25:c25a:d00a:f42a/1282c19:dd:d9:dd:c25:c25a:d00a:f42a
442c19:dd:d9:dd:c25:c25a:d00a:f42b/1282c19:dd:d9:dd:c25:c25a:d00a:f42b
452c19:dd:d9:dd:c25:c25a:d00a:f42c/1282c19:dd:d9:dd:c25:c25a:d00a:f42c
462c19:dd:d9:dd:c25:c25a:d00a:f42d/1282c19:dd:d9:dd:c25:c25a:d00a:f42d
472c19:dd:d9:dd:c25:c25a:d00a:f42e/1282c19:dd:d9:dd:c25:c25a:d00a:f42e
482c19:dd:d9:dd:c25:c25a:d00a:f42f/1282c19:dd:d9:dd:c25:c25a:d00a:f42f
492c19:dd:d9:dd:c25:c25a:d00a:f430/1282c19:dd:d9:dd:c25:c25a:d00a:f430
502c19:dd:d9:dd:c25:c25a:d00a:f431/1282c19:dd:d9:dd:c25:c25a:d00a:f431
512c19:dd:d9:dd:c25:c25a:d00a:f432/1282c19:dd:d9:dd:c25:c25a:d00a:f432
522c19:dd:d9:dd:c25:c25a:d00a:f433/1282c19:dd:d9:dd:c25:c25a:d00a:f433
532c19:dd:d9:dd:c25:c25a:d00a:f434/1282c19:dd:d9:dd:c25:c25a:d00a:f434
542c19:dd:d9:dd:c25:c25a:d00a:f435/1282c19:dd:d9:dd:c25:c25a:d00a:f435
552c19:dd:d9:dd:c25:c25a:d00a:f436/1282c19:dd:d9:dd:c25:c25a:d00a:f436
562c19:dd:d9:dd:c25:c25a:d00a:f437/1282c19:dd:d9:dd:c25:c25a:d00a:f437
572c19:dd:d9:dd:c25:c25a:d00a:f438/1282c19:dd:d9:dd:c25:c25a:d00a:f438
582c19:dd:d9:dd:c25:c25a:d00a:f439/1282c19:dd:d9:dd:c25:c25a:d00a:f439
592c19:dd:d9:dd:c25:c25a:d00a:f43a/1282c19:dd:d9:dd:c25:c25a:d00a:f43a
602c19:dd:d9:dd:c25:c25a:d00a:f43b/1282c19:dd:d9:dd:c25:c25a:d00a:f43b
612c19:dd:d9:dd:c25:c25a:d00a:f43c/1282c19:dd:d9:dd:c25:c25a:d00a:f43c
622c19:dd:d9:dd:c25:c25a:d00a:f43d/1282c19:dd:d9:dd:c25:c25a:d00a:f43d
632c19:dd:d9:dd:c25:c25a:d00a:f43e/1282c19:dd:d9:dd:c25:c25a:d00a:f43e
642c19:dd:d9:dd:c25:c25a:d00a:f43f/1282c19:dd:d9:dd:c25:c25a:d00a:f43f
652c19:dd:d9:dd:c25:c25a:d00a:f440/1282c19:dd:d9:dd:c25:c25a:d00a:f440
662c19:dd:d9:dd:c25:c25a:d00a:f441/1282c19:dd:d9:dd:c25:c25a:d00a:f441
672c19:dd:d9:dd:c25:c25a:d00a:f442/1282c19:dd:d9:dd:c25:c25a:d00a:f442
682c19:dd:d9:dd:c25:c25a:d00a:f443/1282c19:dd:d9:dd:c25:c25a:d00a:f443
692c19:dd:d9:dd:c25:c25a:d00a:f444/1282c19:dd:d9:dd:c25:c25a:d00a:f444
702c19:dd:d9:dd:c25:c25a:d00a:f445/1282c19:dd:d9:dd:c25:c25a:d00a:f445
712c19:dd:d9:dd:c25:c25a:d00a:f446/1282c19:dd:d9:dd:c25:c25a:d00a:f446
722c19:dd:d9:dd:c25:c25a:d00a:f447/1282c19:dd:d9:dd:c25:c25a:d00a:f447
732c19:dd:d9:dd:c25:c25a:d00a:f448/1282c19:dd:d9:dd:c25:c25a:d00a:f448
742c19:dd:d9:dd:c25:c25a:d00a:f449/1282c19:dd:d9:dd:c25:c25a:d00a:f449
752c19:dd:d9:dd:c25:c25a:d00a:f44a/1282c19:dd:d9:dd:c25:c25a:d00a:f44a
762c19:dd:d9:dd:c25:c25a:d00a:f44b/1282c19:dd:d9:dd:c25:c25a:d00a:f44b
772c19:dd:d9:dd:c25:c25a:d00a:f44c/1282c19:dd:d9:dd:c25:c25a:d00a:f44c
782c19:dd:d9:dd:c25:c25a:d00a:f44d/1282c19:dd:d9:dd:c25:c25a:d00a:f44d
792c19:dd:d9:dd:c25:c25a:d00a:f44e/1282c19:dd:d9:dd:c25:c25a:d00a:f44e
802c19:dd:d9:dd:c25:c25a:d00a:f44f/1282c19:dd:d9:dd:c25:c25a:d00a:f44f
812c19:dd:d9:dd:c25:c25a:d00a:f450/1282c19:dd:d9:dd:c25:c25a:d00a:f450
822c19:dd:d9:dd:c25:c25a:d00a:f451/1282c19:dd:d9:dd:c25:c25a:d00a:f451
832c19:dd:d9:dd:c25:c25a:d00a:f452/1282c19:dd:d9:dd:c25:c25a:d00a:f452
842c19:dd:d9:dd:c25:c25a:d00a:f453/1282c19:dd:d9:dd:c25:c25a:d00a:f453
852c19:dd:d9:dd:c25:c25a:d00a:f454/1282c19:dd:d9:dd:c25:c25a:d00a:f454
862c19:dd:d9:dd:c25:c25a:d00a:f455/1282c19:dd:d9:dd:c25:c25a:d00a:f455
872c19:dd:d9:dd:c25:c25a:d00a:f456/1282c19:dd:d9:dd:c25:c25a:d00a:f456
882c19:dd:d9:dd:c25:c25a:d00a:f457/1282c19:dd:d9:dd:c25:c25a:d00a:f457
892c19:dd:d9:dd:c25:c25a:d00a:f458/1282c19:dd:d9:dd:c25:c25a:d00a:f458
902c19:dd:d9:dd:c25:c25a:d00a:f459/1282c19:dd:d9:dd:c25:c25a:d00a:f459
912c19:dd:d9:dd:c25:c25a:d00a:f45a/1282c19:dd:d9:dd:c25:c25a:d00a:f45a
922c19:dd:d9:dd:c25:c25a:d00a:f45b/1282c19:dd:d9:dd:c25:c25a:d00a:f45b
932c19:dd:d9:dd:c25:c25a:d00a:f45c/1282c19:dd:d9:dd:c25:c25a:d00a:f45c
942c19:dd:d9:dd:c25:c25a:d00a:f45d/1282c19:dd:d9:dd:c25:c25a:d00a:f45d
952c19:dd:d9:dd:c25:c25a:d00a:f45e/1282c19:dd:d9:dd:c25:c25a:d00a:f45e
962c19:dd:d9:dd:c25:c25a:d00a:f45f/1282c19:dd:d9:dd:c25:c25a:d00a:f45f
972c19:dd:d9:dd:c25:c25a:d00a:f460/1282c19:dd:d9:dd:c25:c25a:d00a:f460
982c19:dd:d9:dd:c25:c25a:d00a:f461/1282c19:dd:d9:dd:c25:c25a:d00a:f461
992c19:dd:d9:dd:c25:c25a:d00a:f462/1282c19:dd:d9:dd:c25:c25a:d00a:f462
1002c19:dd:d9:dd:c25:c25a:d00a:f463/1282c19:dd:d9:dd:c25:c25a:d00a:f463
1012c19:dd:d9:dd:c25:c25a:d00a:f464/1282c19:dd:d9:dd:c25:c25a:d00a:f464
1022c19:dd:d9:dd:c25:c25a:d00a:f465/1282c19:dd:d9:dd:c25:c25a:d00a:f465
1032c19:dd:d9:dd:c25:c25a:d00a:f466/1282c19:dd:d9:dd:c25:c25a:d00a:f466
1042c19:dd:d9:dd:c25:c25a:d00a:f467/1282c19:dd:d9:dd:c25:c25a:d00a:f467
1052c19:dd:d9:dd:c25:c25a:d00a:f468/1282c19:dd:d9:dd:c25:c25a:d00a:f468
1062c19:dd:d9:dd:c25:c25a:d00a:f469/1282c19:dd:d9:dd:c25:c25a:d00a:f469
1072c19:dd:d9:dd:c25:c25a:d00a:f46a/1282c19:dd:d9:dd:c25:c25a:d00a:f46a
1082c19:dd:d9:dd:c25:c25a:d00a:f46b/1282c19:dd:d9:dd:c25:c25a:d00a:f46b
1092c19:dd:d9:dd:c25:c25a:d00a:f46c/1282c19:dd:d9:dd:c25:c25a:d00a:f46c
1102c19:dd:d9:dd:c25:c25a:d00a:f46d/1282c19:dd:d9:dd:c25:c25a:d00a:f46d
1112c19:dd:d9:dd:c25:c25a:d00a:f46e/1282c19:dd:d9:dd:c25:c25a:d00a:f46e
1122c19:dd:d9:dd:c25:c25a:d00a:f46f/1282c19:dd:d9:dd:c25:c25a:d00a:f46f
1132c19:dd:d9:dd:c25:c25a:d00a:f470/1282c19:dd:d9:dd:c25:c25a:d00a:f470
1142c19:dd:d9:dd:c25:c25a:d00a:f471/1282c19:dd:d9:dd:c25:c25a:d00a:f471
1152c19:dd:d9:dd:c25:c25a:d00a:f472/1282c19:dd:d9:dd:c25:c25a:d00a:f472
1162c19:dd:d9:dd:c25:c25a:d00a:f473/1282c19:dd:d9:dd:c25:c25a:d00a:f473
1172c19:dd:d9:dd:c25:c25a:d00a:f474/1282c19:dd:d9:dd:c25:c25a:d00a:f474
1182c19:dd:d9:dd:c25:c25a:d00a:f475/1282c19:dd:d9:dd:c25:c25a:d00a:f475
1192c19:dd:d9:dd:c25:c25a:d00a:f476/1282c19:dd:d9:dd:c25:c25a:d00a:f476
1202c19:dd:d9:dd:c25:c25a:d00a:f477/1282c19:dd:d9:dd:c25:c25a:d00a:f477
1212c19:dd:d9:dd:c25:c25a:d00a:f478/1282c19:dd:d9:dd:c25:c25a:d00a:f478
1222c19:dd:d9:dd:c25:c25a:d00a:f479/1282c19:dd:d9:dd:c25:c25a:d00a:f479
1232c19:dd:d9:dd:c25:c25a:d00a:f47a/1282c19:dd:d9:dd:c25:c25a:d00a:f47a
1242c19:dd:d9:dd:c25:c25a:d00a:f47b/1282c19:dd:d9:dd:c25:c25a:d00a:f47b
1252c19:dd:d9:dd:c25:c25a:d00a:f47c/1282c19:dd:d9:dd:c25:c25a:d00a:f47c
1262c19:dd:d9:dd:c25:c25a:d00a:f47d/1282c19:dd:d9:dd:c25:c25a:d00a:f47d
1272c19:dd:d9:dd:c25:c25a:d00a:f47e/1282c19:dd:d9:dd:c25:c25a:d00a:f47e
1282c19:dd:d9:dd:c25:c25a:d00a:f47f/1282c19:dd:d9:dd:c25:c25a:d00a:f47f
1292c19:dd:d9:dd:c25:c25a:d00a:f480/1282c19:dd:d9:dd:c25:c25a:d00a:f480
1302c19:dd:d9:dd:c25:c25a:d00a:f481/1282c19:dd:d9:dd:c25:c25a:d00a:f481
1312c19:dd:d9:dd:c25:c25a:d00a:f482/1282c19:dd:d9:dd:c25:c25a:d00a:f482
1322c19:dd:d9:dd:c25:c25a:d00a:f483/1282c19:dd:d9:dd:c25:c25a:d00a:f483
1332c19:dd:d9:dd:c25:c25a:d00a:f484/1282c19:dd:d9:dd:c25:c25a:d00a:f484
1342c19:dd:d9:dd:c25:c25a:d00a:f485/1282c19:dd:d9:dd:c25:c25a:d00a:f485
1352c19:dd:d9:dd:c25:c25a:d00a:f486/1282c19:dd:d9:dd:c25:c25a:d00a:f486
1362c19:dd:d9:dd:c25:c25a:d00a:f487/1282c19:dd:d9:dd:c25:c25a:d00a:f487
1372c19:dd:d9:dd:c25:c25a:d00a:f488/1282c19:dd:d9:dd:c25:c25a:d00a:f488
1382c19:dd:d9:dd:c25:c25a:d00a:f489/1282c19:dd:d9:dd:c25:c25a:d00a:f489
1392c19:dd:d9:dd:c25:c25a:d00a:f48a/1282c19:dd:d9:dd:c25:c25a:d00a:f48a
1402c19:dd:d9:dd:c25:c25a:d00a:f48b/1282c19:dd:d9:dd:c25:c25a:d00a:f48b
1412c19:dd:d9:dd:c25:c25a:d00a:f48c/1282c19:dd:d9:dd:c25:c25a:d00a:f48c
1422c19:dd:d9:dd:c25:c25a:d00a:f48d/1282c19:dd:d9:dd:c25:c25a:d00a:f48d
1432c19:dd:d9:dd:c25:c25a:d00a:f48e/1282c19:dd:d9:dd:c25:c25a:d00a:f48e
1442c19:dd:d9:dd:c25:c25a:d00a:f48f/1282c19:dd:d9:dd:c25:c25a:d00a:f48f
1452c19:dd:d9:dd:c25:c25a:d00a:f490/1282c19:dd:d9:dd:c25:c25a:d00a:f490
1462c19:dd:d9:dd:c25:c25a:d00a:f491/1282c19:dd:d9:dd:c25:c25a:d00a:f491
1472c19:dd:d9:dd:c25:c25a:d00a:f492/1282c19:dd:d9:dd:c25:c25a:d00a:f492
1482c19:dd:d9:dd:c25:c25a:d00a:f493/1282c19:dd:d9:dd:c25:c25a:d00a:f493
1492c19:dd:d9:dd:c25:c25a:d00a:f494/1282c19:dd:d9:dd:c25:c25a:d00a:f494
1502c19:dd:d9:dd:c25:c25a:d00a:f495/1282c19:dd:d9:dd:c25:c25a:d00a:f495
1512c19:dd:d9:dd:c25:c25a:d00a:f496/1282c19:dd:d9:dd:c25:c25a:d00a:f496
1522c19:dd:d9:dd:c25:c25a:d00a:f497/1282c19:dd:d9:dd:c25:c25a:d00a:f497
1532c19:dd:d9:dd:c25:c25a:d00a:f498/1282c19:dd:d9:dd:c25:c25a:d00a:f498
1542c19:dd:d9:dd:c25:c25a:d00a:f499/1282c19:dd:d9:dd:c25:c25a:d00a:f499
1552c19:dd:d9:dd:c25:c25a:d00a:f49a/1282c19:dd:d9:dd:c25:c25a:d00a:f49a
1562c19:dd:d9:dd:c25:c25a:d00a:f49b/1282c19:dd:d9:dd:c25:c25a:d00a:f49b
1572c19:dd:d9:dd:c25:c25a:d00a:f49c/1282c19:dd:d9:dd:c25:c25a:d00a:f49c
1582c19:dd:d9:dd:c25:c25a:d00a:f49d/1282c19:dd:d9:dd:c25:c25a:d00a:f49d
1592c19:dd:d9:dd:c25:c25a:d00a:f49e/1282c19:dd:d9:dd:c25:c25a:d00a:f49e
1602c19:dd:d9:dd:c25:c25a:d00a:f49f/1282c19:dd:d9:dd:c25:c25a:d00a:f49f
1612c19:dd:d9:dd:c25:c25a:d00a:f4a0/1282c19:dd:d9:dd:c25:c25a:d00a:f4a0
1622c19:dd:d9:dd:c25:c25a:d00a:f4a1/1282c19:dd:d9:dd:c25:c25a:d00a:f4a1
1632c19:dd:d9:dd:c25:c25a:d00a:f4a2/1282c19:dd:d9:dd:c25:c25a:d00a:f4a2
1642c19:dd:d9:dd:c25:c25a:d00a:f4a3/1282c19:dd:d9:dd:c25:c25a:d00a:f4a3
1652c19:dd:d9:dd:c25:c25a:d00a:f4a4/1282c19:dd:d9:dd:c25:c25a:d00a:f4a4
1662c19:dd:d9:dd:c25:c25a:d00a:f4a5/1282c19:dd:d9:dd:c25:c25a:d00a:f4a5
1672c19:dd:d9:dd:c25:c25a:d00a:f4a6/1282c19:dd:d9:dd:c25:c25a:d00a:f4a6
1682c19:dd:d9:dd:c25:c25a:d00a:f4a7/1282c19:dd:d9:dd:c25:c25a:d00a:f4a7
1692c19:dd:d9:dd:c25:c25a:d00a:f4a8/1282c19:dd:d9:dd:c25:c25a:d00a:f4a8
1702c19:dd:d9:dd:c25:c25a:d00a:f4a9/1282c19:dd:d9:dd:c25:c25a:d00a:f4a9
1712c19:dd:d9:dd:c25:c25a:d00a:f4aa/1282c19:dd:d9:dd:c25:c25a:d00a:f4aa
1722c19:dd:d9:dd:c25:c25a:d00a:f4ab/1282c19:dd:d9:dd:c25:c25a:d00a:f4ab
1732c19:dd:d9:dd:c25:c25a:d00a:f4ac/1282c19:dd:d9:dd:c25:c25a:d00a:f4ac
1742c19:dd:d9:dd:c25:c25a:d00a:f4ad/1282c19:dd:d9:dd:c25:c25a:d00a:f4ad
1752c19:dd:d9:dd:c25:c25a:d00a:f4ae/1282c19:dd:d9:dd:c25:c25a:d00a:f4ae
1762c19:dd:d9:dd:c25:c25a:d00a:f4af/1282c19:dd:d9:dd:c25:c25a:d00a:f4af
1772c19:dd:d9:dd:c25:c25a:d00a:f4b0/1282c19:dd:d9:dd:c25:c25a:d00a:f4b0
1782c19:dd:d9:dd:c25:c25a:d00a:f4b1/1282c19:dd:d9:dd:c25:c25a:d00a:f4b1
1792c19:dd:d9:dd:c25:c25a:d00a:f4b2/1282c19:dd:d9:dd:c25:c25a:d00a:f4b2
1802c19:dd:d9:dd:c25:c25a:d00a:f4b3/1282c19:dd:d9:dd:c25:c25a:d00a:f4b3
1812c19:dd:d9:dd:c25:c25a:d00a:f4b4/1282c19:dd:d9:dd:c25:c25a:d00a:f4b4
1822c19:dd:d9:dd:c25:c25a:d00a:f4b5/1282c19:dd:d9:dd:c25:c25a:d00a:f4b5
1832c19:dd:d9:dd:c25:c25a:d00a:f4b6/1282c19:dd:d9:dd:c25:c25a:d00a:f4b6
1842c19:dd:d9:dd:c25:c25a:d00a:f4b7/1282c19:dd:d9:dd:c25:c25a:d00a:f4b7
1852c19:dd:d9:dd:c25:c25a:d00a:f4b8/1282c19:dd:d9:dd:c25:c25a:d00a:f4b8
1862c19:dd:d9:dd:c25:c25a:d00a:f4b9/1282c19:dd:d9:dd:c25:c25a:d00a:f4b9
1872c19:dd:d9:dd:c25:c25a:d00a:f4ba/1282c19:dd:d9:dd:c25:c25a:d00a:f4ba
1882c19:dd:d9:dd:c25:c25a:d00a:f4bb/1282c19:dd:d9:dd:c25:c25a:d00a:f4bb
1892c19:dd:d9:dd:c25:c25a:d00a:f4bc/1282c19:dd:d9:dd:c25:c25a:d00a:f4bc
1902c19:dd:d9:dd:c25:c25a:d00a:f4bd/1282c19:dd:d9:dd:c25:c25a:d00a:f4bd
1912c19:dd:d9:dd:c25:c25a:d00a:f4be/1282c19:dd:d9:dd:c25:c25a:d00a:f4be
1922c19:dd:d9:dd:c25:c25a:d00a:f4bf/1282c19:dd:d9:dd:c25:c25a:d00a:f4bf
1932c19:dd:d9:dd:c25:c25a:d00a:f4c0/1282c19:dd:d9:dd:c25:c25a:d00a:f4c0
1942c19:dd:d9:dd:c25:c25a:d00a:f4c1/1282c19:dd:d9:dd:c25:c25a:d00a:f4c1
1952c19:dd:d9:dd:c25:c25a:d00a:f4c2/1282c19:dd:d9:dd:c25:c25a:d00a:f4c2
1962c19:dd:d9:dd:c25:c25a:d00a:f4c3/1282c19:dd:d9:dd:c25:c25a:d00a:f4c3
1972c19:dd:d9:dd:c25:c25a:d00a:f4c4/1282c19:dd:d9:dd:c25:c25a:d00a:f4c4
1982c19:dd:d9:dd:c25:c25a:d00a:f4c5/1282c19:dd:d9:dd:c25:c25a:d00a:f4c5
1992c19:dd:d9:dd:c25:c25a:d00a:f4c6/1282c19:dd:d9:dd:c25:c25a:d00a:f4c6
2002c19:dd:d9:dd:c25:c25a:d00a:f4c7/1282c19:dd:d9:dd:c25:c25a:d00a:f4c7
2012c19:dd:d9:dd:c25:c25a:d00a:f4c8/1282c19:dd:d9:dd:c25:c25a:d00a:f4c8
2022c19:dd:d9:dd:c25:c25a:d00a:f4c9/1282c19:dd:d9:dd:c25:c25a:d00a:f4c9
2032c19:dd:d9:dd:c25:c25a:d00a:f4ca/1282c19:dd:d9:dd:c25:c25a:d00a:f4ca
2042c19:dd:d9:dd:c25:c25a:d00a:f4cb/1282c19:dd:d9:dd:c25:c25a:d00a:f4cb
2052c19:dd:d9:dd:c25:c25a:d00a:f4cc/1282c19:dd:d9:dd:c25:c25a:d00a:f4cc
2062c19:dd:d9:dd:c25:c25a:d00a:f4cd/1282c19:dd:d9:dd:c25:c25a:d00a:f4cd
2072c19:dd:d9:dd:c25:c25a:d00a:f4ce/1282c19:dd:d9:dd:c25:c25a:d00a:f4ce
2082c19:dd:d9:dd:c25:c25a:d00a:f4cf/1282c19:dd:d9:dd:c25:c25a:d00a:f4cf
2092c19:dd:d9:dd:c25:c25a:d00a:f4d0/1282c19:dd:d9:dd:c25:c25a:d00a:f4d0
2102c19:dd:d9:dd:c25:c25a:d00a:f4d1/1282c19:dd:d9:dd:c25:c25a:d00a:f4d1
2112c19:dd:d9:dd:c25:c25a:d00a:f4d2/1282c19:dd:d9:dd:c25:c25a:d00a:f4d2
2122c19:dd:d9:dd:c25:c25a:d00a:f4d3/1282c19:dd:d9:dd:c25:c25a:d00a:f4d3
2132c19:dd:d9:dd:c25:c25a:d00a:f4d4/1282c19:dd:d9:dd:c25:c25a:d00a:f4d4
2142c19:dd:d9:dd:c25:c25a:d00a:f4d5/1282c19:dd:d9:dd:c25:c25a:d00a:f4d5
2152c19:dd:d9:dd:c25:c25a:d00a:f4d6/1282c19:dd:d9:dd:c25:c25a:d00a:f4d6
2162c19:dd:d9:dd:c25:c25a:d00a:f4d7/1282c19:dd:d9:dd:c25:c25a:d00a:f4d7
2172c19:dd:d9:dd:c25:c25a:d00a:f4d8/1282c19:dd:d9:dd:c25:c25a:d00a:f4d8
2182c19:dd:d9:dd:c25:c25a:d00a:f4d9/1282c19:dd:d9:dd:c25:c25a:d00a:f4d9
2192c19:dd:d9:dd:c25:c25a:d00a:f4da/1282c19:dd:d9:dd:c25:c25a:d00a:f4da
2202c19:dd:d9:dd:c25:c25a:d00a:f4db/1282c19:dd:d9:dd:c25:c25a:d00a:f4db
2212c19:dd:d9:dd:c25:c25a:d00a:f4dc/1282c19:dd:d9:dd:c25:c25a:d00a:f4dc
2222c19:dd:d9:dd:c25:c25a:d00a:f4dd/1282c19:dd:d9:dd:c25:c25a:d00a:f4dd
2232c19:dd:d9:dd:c25:c25a:d00a:f4de/1282c19:dd:d9:dd:c25:c25a:d00a:f4de
2242c19:dd:d9:dd:c25:c25a:d00a:f4df/1282c19:dd:d9:dd:c25:c25a:d00a:f4df
2252c19:dd:d9:dd:c25:c25a:d00a:f4e0/1282c19:dd:d9:dd:c25:c25a:d00a:f4e0
2262c19:dd:d9:dd:c25:c25a:d00a:f4e1/1282c19:dd:d9:dd:c25:c25a:d00a:f4e1
2272c19:dd:d9:dd:c25:c25a:d00a:f4e2/1282c19:dd:d9:dd:c25:c25a:d00a:f4e2
2282c19:dd:d9:dd:c25:c25a:d00a:f4e3/1282c19:dd:d9:dd:c25:c25a:d00a:f4e3
2292c19:dd:d9:dd:c25:c25a:d00a:f4e4/1282c19:dd:d9:dd:c25:c25a:d00a:f4e4
2302c19:dd:d9:dd:c25:c25a:d00a:f4e5/1282c19:dd:d9:dd:c25:c25a:d00a:f4e5
2312c19:dd:d9:dd:c25:c25a:d00a:f4e6/1282c19:dd:d9:dd:c25:c25a:d00a:f4e6
2322c19:dd:d9:dd:c25:c25a:d00a:f4e7/1282c19:dd:d9:dd:c25:c25a:d00a:f4e7
2332c19:dd:d9:dd:c25:c25a:d00a:f4e8/1282c19:dd:d9:dd:c25:c25a:d00a:f4e8
2342c19:dd:d9:dd:c25:c25a:d00a:f4e9/1282c19:dd:d9:dd:c25:c25a:d00a:f4e9
2352c19:dd:d9:dd:c25:c25a:d00a:f4ea/1282c19:dd:d9:dd:c25:c25a:d00a:f4ea
2362c19:dd:d9:dd:c25:c25a:d00a:f4eb/1282c19:dd:d9:dd:c25:c25a:d00a:f4eb
2372c19:dd:d9:dd:c25:c25a:d00a:f4ec/1282c19:dd:d9:dd:c25:c25a:d00a:f4ec
2382c19:dd:d9:dd:c25:c25a:d00a:f4ed/1282c19:dd:d9:dd:c25:c25a:d00a:f4ed
2392c19:dd:d9:dd:c25:c25a:d00a:f4ee/1282c19:dd:d9:dd:c25:c25a:d00a:f4ee
2402c19:dd:d9:dd:c25:c25a:d00a:f4ef/1282c19:dd:d9:dd:c25:c25a:d00a:f4ef
2412c19:dd:d9:dd:c25:c25a:d00a:f4f0/1282c19:dd:d9:dd:c25:c25a:d00a:f4f0
2422c19:dd:d9:dd:c25:c25a:d00a:f4f1/1282c19:dd:d9:dd:c25:c25a:d00a:f4f1
2432c19:dd:d9:dd:c25:c25a:d00a:f4f2/1282c19:dd:d9:dd:c25:c25a:d00a:f4f2
2442c19:dd:d9:dd:c25:c25a:d00a:f4f3/1282c19:dd:d9:dd:c25:c25a:d00a:f4f3
2452c19:dd:d9:dd:c25:c25a:d00a:f4f4/1282c19:dd:d9:dd:c25:c25a:d00a:f4f4
2462c19:dd:d9:dd:c25:c25a:d00a:f4f5/1282c19:dd:d9:dd:c25:c25a:d00a:f4f5
2472c19:dd:d9:dd:c25:c25a:d00a:f4f6/1282c19:dd:d9:dd:c25:c25a:d00a:f4f6
2482c19:dd:d9:dd:c25:c25a:d00a:f4f7/1282c19:dd:d9:dd:c25:c25a:d00a:f4f7
2492c19:dd:d9:dd:c25:c25a:d00a:f4f8/1282c19:dd:d9:dd:c25:c25a:d00a:f4f8
2502c19:dd:d9:dd:c25:c25a:d00a:f4f9/1282c19:dd:d9:dd:c25:c25a:d00a:f4f9
2512c19:dd:d9:dd:c25:c25a:d00a:f4fa/1282c19:dd:d9:dd:c25:c25a:d00a:f4fa
2522c19:dd:d9:dd:c25:c25a:d00a:f4fb/1282c19:dd:d9:dd:c25:c25a:d00a:f4fb
2532c19:dd:d9:dd:c25:c25a:d00a:f4fc/1282c19:dd:d9:dd:c25:c25a:d00a:f4fc
2542c19:dd:d9:dd:c25:c25a:d00a:f4fd/1282c19:dd:d9:dd:c25:c25a:d00a:f4fd
2552c19:dd:d9:dd:c25:c25a:d00a:f4fe/1282c19:dd:d9:dd:c25:c25a:d00a:f4fe
2562c19:dd:d9:dd:c25:c25a:d00a:f4ff/1282c19:dd:d9:dd:c25:c25a:d00a:f4ff

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.