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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:b400/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:b400
Last address
2c19:dd:d9:dd:c25:c25a:d00a:b4ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:b400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.b.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:b400/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:b400/1282c19:dd:d9:dd:c25:c25a:d00a:b400
22c19:dd:d9:dd:c25:c25a:d00a:b401/1282c19:dd:d9:dd:c25:c25a:d00a:b401
32c19:dd:d9:dd:c25:c25a:d00a:b402/1282c19:dd:d9:dd:c25:c25a:d00a:b402
42c19:dd:d9:dd:c25:c25a:d00a:b403/1282c19:dd:d9:dd:c25:c25a:d00a:b403
52c19:dd:d9:dd:c25:c25a:d00a:b404/1282c19:dd:d9:dd:c25:c25a:d00a:b404
62c19:dd:d9:dd:c25:c25a:d00a:b405/1282c19:dd:d9:dd:c25:c25a:d00a:b405
72c19:dd:d9:dd:c25:c25a:d00a:b406/1282c19:dd:d9:dd:c25:c25a:d00a:b406
82c19:dd:d9:dd:c25:c25a:d00a:b407/1282c19:dd:d9:dd:c25:c25a:d00a:b407
92c19:dd:d9:dd:c25:c25a:d00a:b408/1282c19:dd:d9:dd:c25:c25a:d00a:b408
102c19:dd:d9:dd:c25:c25a:d00a:b409/1282c19:dd:d9:dd:c25:c25a:d00a:b409
112c19:dd:d9:dd:c25:c25a:d00a:b40a/1282c19:dd:d9:dd:c25:c25a:d00a:b40a
122c19:dd:d9:dd:c25:c25a:d00a:b40b/1282c19:dd:d9:dd:c25:c25a:d00a:b40b
132c19:dd:d9:dd:c25:c25a:d00a:b40c/1282c19:dd:d9:dd:c25:c25a:d00a:b40c
142c19:dd:d9:dd:c25:c25a:d00a:b40d/1282c19:dd:d9:dd:c25:c25a:d00a:b40d
152c19:dd:d9:dd:c25:c25a:d00a:b40e/1282c19:dd:d9:dd:c25:c25a:d00a:b40e
162c19:dd:d9:dd:c25:c25a:d00a:b40f/1282c19:dd:d9:dd:c25:c25a:d00a:b40f
172c19:dd:d9:dd:c25:c25a:d00a:b410/1282c19:dd:d9:dd:c25:c25a:d00a:b410
182c19:dd:d9:dd:c25:c25a:d00a:b411/1282c19:dd:d9:dd:c25:c25a:d00a:b411
192c19:dd:d9:dd:c25:c25a:d00a:b412/1282c19:dd:d9:dd:c25:c25a:d00a:b412
202c19:dd:d9:dd:c25:c25a:d00a:b413/1282c19:dd:d9:dd:c25:c25a:d00a:b413
212c19:dd:d9:dd:c25:c25a:d00a:b414/1282c19:dd:d9:dd:c25:c25a:d00a:b414
222c19:dd:d9:dd:c25:c25a:d00a:b415/1282c19:dd:d9:dd:c25:c25a:d00a:b415
232c19:dd:d9:dd:c25:c25a:d00a:b416/1282c19:dd:d9:dd:c25:c25a:d00a:b416
242c19:dd:d9:dd:c25:c25a:d00a:b417/1282c19:dd:d9:dd:c25:c25a:d00a:b417
252c19:dd:d9:dd:c25:c25a:d00a:b418/1282c19:dd:d9:dd:c25:c25a:d00a:b418
262c19:dd:d9:dd:c25:c25a:d00a:b419/1282c19:dd:d9:dd:c25:c25a:d00a:b419
272c19:dd:d9:dd:c25:c25a:d00a:b41a/1282c19:dd:d9:dd:c25:c25a:d00a:b41a
282c19:dd:d9:dd:c25:c25a:d00a:b41b/1282c19:dd:d9:dd:c25:c25a:d00a:b41b
292c19:dd:d9:dd:c25:c25a:d00a:b41c/1282c19:dd:d9:dd:c25:c25a:d00a:b41c
302c19:dd:d9:dd:c25:c25a:d00a:b41d/1282c19:dd:d9:dd:c25:c25a:d00a:b41d
312c19:dd:d9:dd:c25:c25a:d00a:b41e/1282c19:dd:d9:dd:c25:c25a:d00a:b41e
322c19:dd:d9:dd:c25:c25a:d00a:b41f/1282c19:dd:d9:dd:c25:c25a:d00a:b41f
332c19:dd:d9:dd:c25:c25a:d00a:b420/1282c19:dd:d9:dd:c25:c25a:d00a:b420
342c19:dd:d9:dd:c25:c25a:d00a:b421/1282c19:dd:d9:dd:c25:c25a:d00a:b421
352c19:dd:d9:dd:c25:c25a:d00a:b422/1282c19:dd:d9:dd:c25:c25a:d00a:b422
362c19:dd:d9:dd:c25:c25a:d00a:b423/1282c19:dd:d9:dd:c25:c25a:d00a:b423
372c19:dd:d9:dd:c25:c25a:d00a:b424/1282c19:dd:d9:dd:c25:c25a:d00a:b424
382c19:dd:d9:dd:c25:c25a:d00a:b425/1282c19:dd:d9:dd:c25:c25a:d00a:b425
392c19:dd:d9:dd:c25:c25a:d00a:b426/1282c19:dd:d9:dd:c25:c25a:d00a:b426
402c19:dd:d9:dd:c25:c25a:d00a:b427/1282c19:dd:d9:dd:c25:c25a:d00a:b427
412c19:dd:d9:dd:c25:c25a:d00a:b428/1282c19:dd:d9:dd:c25:c25a:d00a:b428
422c19:dd:d9:dd:c25:c25a:d00a:b429/1282c19:dd:d9:dd:c25:c25a:d00a:b429
432c19:dd:d9:dd:c25:c25a:d00a:b42a/1282c19:dd:d9:dd:c25:c25a:d00a:b42a
442c19:dd:d9:dd:c25:c25a:d00a:b42b/1282c19:dd:d9:dd:c25:c25a:d00a:b42b
452c19:dd:d9:dd:c25:c25a:d00a:b42c/1282c19:dd:d9:dd:c25:c25a:d00a:b42c
462c19:dd:d9:dd:c25:c25a:d00a:b42d/1282c19:dd:d9:dd:c25:c25a:d00a:b42d
472c19:dd:d9:dd:c25:c25a:d00a:b42e/1282c19:dd:d9:dd:c25:c25a:d00a:b42e
482c19:dd:d9:dd:c25:c25a:d00a:b42f/1282c19:dd:d9:dd:c25:c25a:d00a:b42f
492c19:dd:d9:dd:c25:c25a:d00a:b430/1282c19:dd:d9:dd:c25:c25a:d00a:b430
502c19:dd:d9:dd:c25:c25a:d00a:b431/1282c19:dd:d9:dd:c25:c25a:d00a:b431
512c19:dd:d9:dd:c25:c25a:d00a:b432/1282c19:dd:d9:dd:c25:c25a:d00a:b432
522c19:dd:d9:dd:c25:c25a:d00a:b433/1282c19:dd:d9:dd:c25:c25a:d00a:b433
532c19:dd:d9:dd:c25:c25a:d00a:b434/1282c19:dd:d9:dd:c25:c25a:d00a:b434
542c19:dd:d9:dd:c25:c25a:d00a:b435/1282c19:dd:d9:dd:c25:c25a:d00a:b435
552c19:dd:d9:dd:c25:c25a:d00a:b436/1282c19:dd:d9:dd:c25:c25a:d00a:b436
562c19:dd:d9:dd:c25:c25a:d00a:b437/1282c19:dd:d9:dd:c25:c25a:d00a:b437
572c19:dd:d9:dd:c25:c25a:d00a:b438/1282c19:dd:d9:dd:c25:c25a:d00a:b438
582c19:dd:d9:dd:c25:c25a:d00a:b439/1282c19:dd:d9:dd:c25:c25a:d00a:b439
592c19:dd:d9:dd:c25:c25a:d00a:b43a/1282c19:dd:d9:dd:c25:c25a:d00a:b43a
602c19:dd:d9:dd:c25:c25a:d00a:b43b/1282c19:dd:d9:dd:c25:c25a:d00a:b43b
612c19:dd:d9:dd:c25:c25a:d00a:b43c/1282c19:dd:d9:dd:c25:c25a:d00a:b43c
622c19:dd:d9:dd:c25:c25a:d00a:b43d/1282c19:dd:d9:dd:c25:c25a:d00a:b43d
632c19:dd:d9:dd:c25:c25a:d00a:b43e/1282c19:dd:d9:dd:c25:c25a:d00a:b43e
642c19:dd:d9:dd:c25:c25a:d00a:b43f/1282c19:dd:d9:dd:c25:c25a:d00a:b43f
652c19:dd:d9:dd:c25:c25a:d00a:b440/1282c19:dd:d9:dd:c25:c25a:d00a:b440
662c19:dd:d9:dd:c25:c25a:d00a:b441/1282c19:dd:d9:dd:c25:c25a:d00a:b441
672c19:dd:d9:dd:c25:c25a:d00a:b442/1282c19:dd:d9:dd:c25:c25a:d00a:b442
682c19:dd:d9:dd:c25:c25a:d00a:b443/1282c19:dd:d9:dd:c25:c25a:d00a:b443
692c19:dd:d9:dd:c25:c25a:d00a:b444/1282c19:dd:d9:dd:c25:c25a:d00a:b444
702c19:dd:d9:dd:c25:c25a:d00a:b445/1282c19:dd:d9:dd:c25:c25a:d00a:b445
712c19:dd:d9:dd:c25:c25a:d00a:b446/1282c19:dd:d9:dd:c25:c25a:d00a:b446
722c19:dd:d9:dd:c25:c25a:d00a:b447/1282c19:dd:d9:dd:c25:c25a:d00a:b447
732c19:dd:d9:dd:c25:c25a:d00a:b448/1282c19:dd:d9:dd:c25:c25a:d00a:b448
742c19:dd:d9:dd:c25:c25a:d00a:b449/1282c19:dd:d9:dd:c25:c25a:d00a:b449
752c19:dd:d9:dd:c25:c25a:d00a:b44a/1282c19:dd:d9:dd:c25:c25a:d00a:b44a
762c19:dd:d9:dd:c25:c25a:d00a:b44b/1282c19:dd:d9:dd:c25:c25a:d00a:b44b
772c19:dd:d9:dd:c25:c25a:d00a:b44c/1282c19:dd:d9:dd:c25:c25a:d00a:b44c
782c19:dd:d9:dd:c25:c25a:d00a:b44d/1282c19:dd:d9:dd:c25:c25a:d00a:b44d
792c19:dd:d9:dd:c25:c25a:d00a:b44e/1282c19:dd:d9:dd:c25:c25a:d00a:b44e
802c19:dd:d9:dd:c25:c25a:d00a:b44f/1282c19:dd:d9:dd:c25:c25a:d00a:b44f
812c19:dd:d9:dd:c25:c25a:d00a:b450/1282c19:dd:d9:dd:c25:c25a:d00a:b450
822c19:dd:d9:dd:c25:c25a:d00a:b451/1282c19:dd:d9:dd:c25:c25a:d00a:b451
832c19:dd:d9:dd:c25:c25a:d00a:b452/1282c19:dd:d9:dd:c25:c25a:d00a:b452
842c19:dd:d9:dd:c25:c25a:d00a:b453/1282c19:dd:d9:dd:c25:c25a:d00a:b453
852c19:dd:d9:dd:c25:c25a:d00a:b454/1282c19:dd:d9:dd:c25:c25a:d00a:b454
862c19:dd:d9:dd:c25:c25a:d00a:b455/1282c19:dd:d9:dd:c25:c25a:d00a:b455
872c19:dd:d9:dd:c25:c25a:d00a:b456/1282c19:dd:d9:dd:c25:c25a:d00a:b456
882c19:dd:d9:dd:c25:c25a:d00a:b457/1282c19:dd:d9:dd:c25:c25a:d00a:b457
892c19:dd:d9:dd:c25:c25a:d00a:b458/1282c19:dd:d9:dd:c25:c25a:d00a:b458
902c19:dd:d9:dd:c25:c25a:d00a:b459/1282c19:dd:d9:dd:c25:c25a:d00a:b459
912c19:dd:d9:dd:c25:c25a:d00a:b45a/1282c19:dd:d9:dd:c25:c25a:d00a:b45a
922c19:dd:d9:dd:c25:c25a:d00a:b45b/1282c19:dd:d9:dd:c25:c25a:d00a:b45b
932c19:dd:d9:dd:c25:c25a:d00a:b45c/1282c19:dd:d9:dd:c25:c25a:d00a:b45c
942c19:dd:d9:dd:c25:c25a:d00a:b45d/1282c19:dd:d9:dd:c25:c25a:d00a:b45d
952c19:dd:d9:dd:c25:c25a:d00a:b45e/1282c19:dd:d9:dd:c25:c25a:d00a:b45e
962c19:dd:d9:dd:c25:c25a:d00a:b45f/1282c19:dd:d9:dd:c25:c25a:d00a:b45f
972c19:dd:d9:dd:c25:c25a:d00a:b460/1282c19:dd:d9:dd:c25:c25a:d00a:b460
982c19:dd:d9:dd:c25:c25a:d00a:b461/1282c19:dd:d9:dd:c25:c25a:d00a:b461
992c19:dd:d9:dd:c25:c25a:d00a:b462/1282c19:dd:d9:dd:c25:c25a:d00a:b462
1002c19:dd:d9:dd:c25:c25a:d00a:b463/1282c19:dd:d9:dd:c25:c25a:d00a:b463
1012c19:dd:d9:dd:c25:c25a:d00a:b464/1282c19:dd:d9:dd:c25:c25a:d00a:b464
1022c19:dd:d9:dd:c25:c25a:d00a:b465/1282c19:dd:d9:dd:c25:c25a:d00a:b465
1032c19:dd:d9:dd:c25:c25a:d00a:b466/1282c19:dd:d9:dd:c25:c25a:d00a:b466
1042c19:dd:d9:dd:c25:c25a:d00a:b467/1282c19:dd:d9:dd:c25:c25a:d00a:b467
1052c19:dd:d9:dd:c25:c25a:d00a:b468/1282c19:dd:d9:dd:c25:c25a:d00a:b468
1062c19:dd:d9:dd:c25:c25a:d00a:b469/1282c19:dd:d9:dd:c25:c25a:d00a:b469
1072c19:dd:d9:dd:c25:c25a:d00a:b46a/1282c19:dd:d9:dd:c25:c25a:d00a:b46a
1082c19:dd:d9:dd:c25:c25a:d00a:b46b/1282c19:dd:d9:dd:c25:c25a:d00a:b46b
1092c19:dd:d9:dd:c25:c25a:d00a:b46c/1282c19:dd:d9:dd:c25:c25a:d00a:b46c
1102c19:dd:d9:dd:c25:c25a:d00a:b46d/1282c19:dd:d9:dd:c25:c25a:d00a:b46d
1112c19:dd:d9:dd:c25:c25a:d00a:b46e/1282c19:dd:d9:dd:c25:c25a:d00a:b46e
1122c19:dd:d9:dd:c25:c25a:d00a:b46f/1282c19:dd:d9:dd:c25:c25a:d00a:b46f
1132c19:dd:d9:dd:c25:c25a:d00a:b470/1282c19:dd:d9:dd:c25:c25a:d00a:b470
1142c19:dd:d9:dd:c25:c25a:d00a:b471/1282c19:dd:d9:dd:c25:c25a:d00a:b471
1152c19:dd:d9:dd:c25:c25a:d00a:b472/1282c19:dd:d9:dd:c25:c25a:d00a:b472
1162c19:dd:d9:dd:c25:c25a:d00a:b473/1282c19:dd:d9:dd:c25:c25a:d00a:b473
1172c19:dd:d9:dd:c25:c25a:d00a:b474/1282c19:dd:d9:dd:c25:c25a:d00a:b474
1182c19:dd:d9:dd:c25:c25a:d00a:b475/1282c19:dd:d9:dd:c25:c25a:d00a:b475
1192c19:dd:d9:dd:c25:c25a:d00a:b476/1282c19:dd:d9:dd:c25:c25a:d00a:b476
1202c19:dd:d9:dd:c25:c25a:d00a:b477/1282c19:dd:d9:dd:c25:c25a:d00a:b477
1212c19:dd:d9:dd:c25:c25a:d00a:b478/1282c19:dd:d9:dd:c25:c25a:d00a:b478
1222c19:dd:d9:dd:c25:c25a:d00a:b479/1282c19:dd:d9:dd:c25:c25a:d00a:b479
1232c19:dd:d9:dd:c25:c25a:d00a:b47a/1282c19:dd:d9:dd:c25:c25a:d00a:b47a
1242c19:dd:d9:dd:c25:c25a:d00a:b47b/1282c19:dd:d9:dd:c25:c25a:d00a:b47b
1252c19:dd:d9:dd:c25:c25a:d00a:b47c/1282c19:dd:d9:dd:c25:c25a:d00a:b47c
1262c19:dd:d9:dd:c25:c25a:d00a:b47d/1282c19:dd:d9:dd:c25:c25a:d00a:b47d
1272c19:dd:d9:dd:c25:c25a:d00a:b47e/1282c19:dd:d9:dd:c25:c25a:d00a:b47e
1282c19:dd:d9:dd:c25:c25a:d00a:b47f/1282c19:dd:d9:dd:c25:c25a:d00a:b47f
1292c19:dd:d9:dd:c25:c25a:d00a:b480/1282c19:dd:d9:dd:c25:c25a:d00a:b480
1302c19:dd:d9:dd:c25:c25a:d00a:b481/1282c19:dd:d9:dd:c25:c25a:d00a:b481
1312c19:dd:d9:dd:c25:c25a:d00a:b482/1282c19:dd:d9:dd:c25:c25a:d00a:b482
1322c19:dd:d9:dd:c25:c25a:d00a:b483/1282c19:dd:d9:dd:c25:c25a:d00a:b483
1332c19:dd:d9:dd:c25:c25a:d00a:b484/1282c19:dd:d9:dd:c25:c25a:d00a:b484
1342c19:dd:d9:dd:c25:c25a:d00a:b485/1282c19:dd:d9:dd:c25:c25a:d00a:b485
1352c19:dd:d9:dd:c25:c25a:d00a:b486/1282c19:dd:d9:dd:c25:c25a:d00a:b486
1362c19:dd:d9:dd:c25:c25a:d00a:b487/1282c19:dd:d9:dd:c25:c25a:d00a:b487
1372c19:dd:d9:dd:c25:c25a:d00a:b488/1282c19:dd:d9:dd:c25:c25a:d00a:b488
1382c19:dd:d9:dd:c25:c25a:d00a:b489/1282c19:dd:d9:dd:c25:c25a:d00a:b489
1392c19:dd:d9:dd:c25:c25a:d00a:b48a/1282c19:dd:d9:dd:c25:c25a:d00a:b48a
1402c19:dd:d9:dd:c25:c25a:d00a:b48b/1282c19:dd:d9:dd:c25:c25a:d00a:b48b
1412c19:dd:d9:dd:c25:c25a:d00a:b48c/1282c19:dd:d9:dd:c25:c25a:d00a:b48c
1422c19:dd:d9:dd:c25:c25a:d00a:b48d/1282c19:dd:d9:dd:c25:c25a:d00a:b48d
1432c19:dd:d9:dd:c25:c25a:d00a:b48e/1282c19:dd:d9:dd:c25:c25a:d00a:b48e
1442c19:dd:d9:dd:c25:c25a:d00a:b48f/1282c19:dd:d9:dd:c25:c25a:d00a:b48f
1452c19:dd:d9:dd:c25:c25a:d00a:b490/1282c19:dd:d9:dd:c25:c25a:d00a:b490
1462c19:dd:d9:dd:c25:c25a:d00a:b491/1282c19:dd:d9:dd:c25:c25a:d00a:b491
1472c19:dd:d9:dd:c25:c25a:d00a:b492/1282c19:dd:d9:dd:c25:c25a:d00a:b492
1482c19:dd:d9:dd:c25:c25a:d00a:b493/1282c19:dd:d9:dd:c25:c25a:d00a:b493
1492c19:dd:d9:dd:c25:c25a:d00a:b494/1282c19:dd:d9:dd:c25:c25a:d00a:b494
1502c19:dd:d9:dd:c25:c25a:d00a:b495/1282c19:dd:d9:dd:c25:c25a:d00a:b495
1512c19:dd:d9:dd:c25:c25a:d00a:b496/1282c19:dd:d9:dd:c25:c25a:d00a:b496
1522c19:dd:d9:dd:c25:c25a:d00a:b497/1282c19:dd:d9:dd:c25:c25a:d00a:b497
1532c19:dd:d9:dd:c25:c25a:d00a:b498/1282c19:dd:d9:dd:c25:c25a:d00a:b498
1542c19:dd:d9:dd:c25:c25a:d00a:b499/1282c19:dd:d9:dd:c25:c25a:d00a:b499
1552c19:dd:d9:dd:c25:c25a:d00a:b49a/1282c19:dd:d9:dd:c25:c25a:d00a:b49a
1562c19:dd:d9:dd:c25:c25a:d00a:b49b/1282c19:dd:d9:dd:c25:c25a:d00a:b49b
1572c19:dd:d9:dd:c25:c25a:d00a:b49c/1282c19:dd:d9:dd:c25:c25a:d00a:b49c
1582c19:dd:d9:dd:c25:c25a:d00a:b49d/1282c19:dd:d9:dd:c25:c25a:d00a:b49d
1592c19:dd:d9:dd:c25:c25a:d00a:b49e/1282c19:dd:d9:dd:c25:c25a:d00a:b49e
1602c19:dd:d9:dd:c25:c25a:d00a:b49f/1282c19:dd:d9:dd:c25:c25a:d00a:b49f
1612c19:dd:d9:dd:c25:c25a:d00a:b4a0/1282c19:dd:d9:dd:c25:c25a:d00a:b4a0
1622c19:dd:d9:dd:c25:c25a:d00a:b4a1/1282c19:dd:d9:dd:c25:c25a:d00a:b4a1
1632c19:dd:d9:dd:c25:c25a:d00a:b4a2/1282c19:dd:d9:dd:c25:c25a:d00a:b4a2
1642c19:dd:d9:dd:c25:c25a:d00a:b4a3/1282c19:dd:d9:dd:c25:c25a:d00a:b4a3
1652c19:dd:d9:dd:c25:c25a:d00a:b4a4/1282c19:dd:d9:dd:c25:c25a:d00a:b4a4
1662c19:dd:d9:dd:c25:c25a:d00a:b4a5/1282c19:dd:d9:dd:c25:c25a:d00a:b4a5
1672c19:dd:d9:dd:c25:c25a:d00a:b4a6/1282c19:dd:d9:dd:c25:c25a:d00a:b4a6
1682c19:dd:d9:dd:c25:c25a:d00a:b4a7/1282c19:dd:d9:dd:c25:c25a:d00a:b4a7
1692c19:dd:d9:dd:c25:c25a:d00a:b4a8/1282c19:dd:d9:dd:c25:c25a:d00a:b4a8
1702c19:dd:d9:dd:c25:c25a:d00a:b4a9/1282c19:dd:d9:dd:c25:c25a:d00a:b4a9
1712c19:dd:d9:dd:c25:c25a:d00a:b4aa/1282c19:dd:d9:dd:c25:c25a:d00a:b4aa
1722c19:dd:d9:dd:c25:c25a:d00a:b4ab/1282c19:dd:d9:dd:c25:c25a:d00a:b4ab
1732c19:dd:d9:dd:c25:c25a:d00a:b4ac/1282c19:dd:d9:dd:c25:c25a:d00a:b4ac
1742c19:dd:d9:dd:c25:c25a:d00a:b4ad/1282c19:dd:d9:dd:c25:c25a:d00a:b4ad
1752c19:dd:d9:dd:c25:c25a:d00a:b4ae/1282c19:dd:d9:dd:c25:c25a:d00a:b4ae
1762c19:dd:d9:dd:c25:c25a:d00a:b4af/1282c19:dd:d9:dd:c25:c25a:d00a:b4af
1772c19:dd:d9:dd:c25:c25a:d00a:b4b0/1282c19:dd:d9:dd:c25:c25a:d00a:b4b0
1782c19:dd:d9:dd:c25:c25a:d00a:b4b1/1282c19:dd:d9:dd:c25:c25a:d00a:b4b1
1792c19:dd:d9:dd:c25:c25a:d00a:b4b2/1282c19:dd:d9:dd:c25:c25a:d00a:b4b2
1802c19:dd:d9:dd:c25:c25a:d00a:b4b3/1282c19:dd:d9:dd:c25:c25a:d00a:b4b3
1812c19:dd:d9:dd:c25:c25a:d00a:b4b4/1282c19:dd:d9:dd:c25:c25a:d00a:b4b4
1822c19:dd:d9:dd:c25:c25a:d00a:b4b5/1282c19:dd:d9:dd:c25:c25a:d00a:b4b5
1832c19:dd:d9:dd:c25:c25a:d00a:b4b6/1282c19:dd:d9:dd:c25:c25a:d00a:b4b6
1842c19:dd:d9:dd:c25:c25a:d00a:b4b7/1282c19:dd:d9:dd:c25:c25a:d00a:b4b7
1852c19:dd:d9:dd:c25:c25a:d00a:b4b8/1282c19:dd:d9:dd:c25:c25a:d00a:b4b8
1862c19:dd:d9:dd:c25:c25a:d00a:b4b9/1282c19:dd:d9:dd:c25:c25a:d00a:b4b9
1872c19:dd:d9:dd:c25:c25a:d00a:b4ba/1282c19:dd:d9:dd:c25:c25a:d00a:b4ba
1882c19:dd:d9:dd:c25:c25a:d00a:b4bb/1282c19:dd:d9:dd:c25:c25a:d00a:b4bb
1892c19:dd:d9:dd:c25:c25a:d00a:b4bc/1282c19:dd:d9:dd:c25:c25a:d00a:b4bc
1902c19:dd:d9:dd:c25:c25a:d00a:b4bd/1282c19:dd:d9:dd:c25:c25a:d00a:b4bd
1912c19:dd:d9:dd:c25:c25a:d00a:b4be/1282c19:dd:d9:dd:c25:c25a:d00a:b4be
1922c19:dd:d9:dd:c25:c25a:d00a:b4bf/1282c19:dd:d9:dd:c25:c25a:d00a:b4bf
1932c19:dd:d9:dd:c25:c25a:d00a:b4c0/1282c19:dd:d9:dd:c25:c25a:d00a:b4c0
1942c19:dd:d9:dd:c25:c25a:d00a:b4c1/1282c19:dd:d9:dd:c25:c25a:d00a:b4c1
1952c19:dd:d9:dd:c25:c25a:d00a:b4c2/1282c19:dd:d9:dd:c25:c25a:d00a:b4c2
1962c19:dd:d9:dd:c25:c25a:d00a:b4c3/1282c19:dd:d9:dd:c25:c25a:d00a:b4c3
1972c19:dd:d9:dd:c25:c25a:d00a:b4c4/1282c19:dd:d9:dd:c25:c25a:d00a:b4c4
1982c19:dd:d9:dd:c25:c25a:d00a:b4c5/1282c19:dd:d9:dd:c25:c25a:d00a:b4c5
1992c19:dd:d9:dd:c25:c25a:d00a:b4c6/1282c19:dd:d9:dd:c25:c25a:d00a:b4c6
2002c19:dd:d9:dd:c25:c25a:d00a:b4c7/1282c19:dd:d9:dd:c25:c25a:d00a:b4c7
2012c19:dd:d9:dd:c25:c25a:d00a:b4c8/1282c19:dd:d9:dd:c25:c25a:d00a:b4c8
2022c19:dd:d9:dd:c25:c25a:d00a:b4c9/1282c19:dd:d9:dd:c25:c25a:d00a:b4c9
2032c19:dd:d9:dd:c25:c25a:d00a:b4ca/1282c19:dd:d9:dd:c25:c25a:d00a:b4ca
2042c19:dd:d9:dd:c25:c25a:d00a:b4cb/1282c19:dd:d9:dd:c25:c25a:d00a:b4cb
2052c19:dd:d9:dd:c25:c25a:d00a:b4cc/1282c19:dd:d9:dd:c25:c25a:d00a:b4cc
2062c19:dd:d9:dd:c25:c25a:d00a:b4cd/1282c19:dd:d9:dd:c25:c25a:d00a:b4cd
2072c19:dd:d9:dd:c25:c25a:d00a:b4ce/1282c19:dd:d9:dd:c25:c25a:d00a:b4ce
2082c19:dd:d9:dd:c25:c25a:d00a:b4cf/1282c19:dd:d9:dd:c25:c25a:d00a:b4cf
2092c19:dd:d9:dd:c25:c25a:d00a:b4d0/1282c19:dd:d9:dd:c25:c25a:d00a:b4d0
2102c19:dd:d9:dd:c25:c25a:d00a:b4d1/1282c19:dd:d9:dd:c25:c25a:d00a:b4d1
2112c19:dd:d9:dd:c25:c25a:d00a:b4d2/1282c19:dd:d9:dd:c25:c25a:d00a:b4d2
2122c19:dd:d9:dd:c25:c25a:d00a:b4d3/1282c19:dd:d9:dd:c25:c25a:d00a:b4d3
2132c19:dd:d9:dd:c25:c25a:d00a:b4d4/1282c19:dd:d9:dd:c25:c25a:d00a:b4d4
2142c19:dd:d9:dd:c25:c25a:d00a:b4d5/1282c19:dd:d9:dd:c25:c25a:d00a:b4d5
2152c19:dd:d9:dd:c25:c25a:d00a:b4d6/1282c19:dd:d9:dd:c25:c25a:d00a:b4d6
2162c19:dd:d9:dd:c25:c25a:d00a:b4d7/1282c19:dd:d9:dd:c25:c25a:d00a:b4d7
2172c19:dd:d9:dd:c25:c25a:d00a:b4d8/1282c19:dd:d9:dd:c25:c25a:d00a:b4d8
2182c19:dd:d9:dd:c25:c25a:d00a:b4d9/1282c19:dd:d9:dd:c25:c25a:d00a:b4d9
2192c19:dd:d9:dd:c25:c25a:d00a:b4da/1282c19:dd:d9:dd:c25:c25a:d00a:b4da
2202c19:dd:d9:dd:c25:c25a:d00a:b4db/1282c19:dd:d9:dd:c25:c25a:d00a:b4db
2212c19:dd:d9:dd:c25:c25a:d00a:b4dc/1282c19:dd:d9:dd:c25:c25a:d00a:b4dc
2222c19:dd:d9:dd:c25:c25a:d00a:b4dd/1282c19:dd:d9:dd:c25:c25a:d00a:b4dd
2232c19:dd:d9:dd:c25:c25a:d00a:b4de/1282c19:dd:d9:dd:c25:c25a:d00a:b4de
2242c19:dd:d9:dd:c25:c25a:d00a:b4df/1282c19:dd:d9:dd:c25:c25a:d00a:b4df
2252c19:dd:d9:dd:c25:c25a:d00a:b4e0/1282c19:dd:d9:dd:c25:c25a:d00a:b4e0
2262c19:dd:d9:dd:c25:c25a:d00a:b4e1/1282c19:dd:d9:dd:c25:c25a:d00a:b4e1
2272c19:dd:d9:dd:c25:c25a:d00a:b4e2/1282c19:dd:d9:dd:c25:c25a:d00a:b4e2
2282c19:dd:d9:dd:c25:c25a:d00a:b4e3/1282c19:dd:d9:dd:c25:c25a:d00a:b4e3
2292c19:dd:d9:dd:c25:c25a:d00a:b4e4/1282c19:dd:d9:dd:c25:c25a:d00a:b4e4
2302c19:dd:d9:dd:c25:c25a:d00a:b4e5/1282c19:dd:d9:dd:c25:c25a:d00a:b4e5
2312c19:dd:d9:dd:c25:c25a:d00a:b4e6/1282c19:dd:d9:dd:c25:c25a:d00a:b4e6
2322c19:dd:d9:dd:c25:c25a:d00a:b4e7/1282c19:dd:d9:dd:c25:c25a:d00a:b4e7
2332c19:dd:d9:dd:c25:c25a:d00a:b4e8/1282c19:dd:d9:dd:c25:c25a:d00a:b4e8
2342c19:dd:d9:dd:c25:c25a:d00a:b4e9/1282c19:dd:d9:dd:c25:c25a:d00a:b4e9
2352c19:dd:d9:dd:c25:c25a:d00a:b4ea/1282c19:dd:d9:dd:c25:c25a:d00a:b4ea
2362c19:dd:d9:dd:c25:c25a:d00a:b4eb/1282c19:dd:d9:dd:c25:c25a:d00a:b4eb
2372c19:dd:d9:dd:c25:c25a:d00a:b4ec/1282c19:dd:d9:dd:c25:c25a:d00a:b4ec
2382c19:dd:d9:dd:c25:c25a:d00a:b4ed/1282c19:dd:d9:dd:c25:c25a:d00a:b4ed
2392c19:dd:d9:dd:c25:c25a:d00a:b4ee/1282c19:dd:d9:dd:c25:c25a:d00a:b4ee
2402c19:dd:d9:dd:c25:c25a:d00a:b4ef/1282c19:dd:d9:dd:c25:c25a:d00a:b4ef
2412c19:dd:d9:dd:c25:c25a:d00a:b4f0/1282c19:dd:d9:dd:c25:c25a:d00a:b4f0
2422c19:dd:d9:dd:c25:c25a:d00a:b4f1/1282c19:dd:d9:dd:c25:c25a:d00a:b4f1
2432c19:dd:d9:dd:c25:c25a:d00a:b4f2/1282c19:dd:d9:dd:c25:c25a:d00a:b4f2
2442c19:dd:d9:dd:c25:c25a:d00a:b4f3/1282c19:dd:d9:dd:c25:c25a:d00a:b4f3
2452c19:dd:d9:dd:c25:c25a:d00a:b4f4/1282c19:dd:d9:dd:c25:c25a:d00a:b4f4
2462c19:dd:d9:dd:c25:c25a:d00a:b4f5/1282c19:dd:d9:dd:c25:c25a:d00a:b4f5
2472c19:dd:d9:dd:c25:c25a:d00a:b4f6/1282c19:dd:d9:dd:c25:c25a:d00a:b4f6
2482c19:dd:d9:dd:c25:c25a:d00a:b4f7/1282c19:dd:d9:dd:c25:c25a:d00a:b4f7
2492c19:dd:d9:dd:c25:c25a:d00a:b4f8/1282c19:dd:d9:dd:c25:c25a:d00a:b4f8
2502c19:dd:d9:dd:c25:c25a:d00a:b4f9/1282c19:dd:d9:dd:c25:c25a:d00a:b4f9
2512c19:dd:d9:dd:c25:c25a:d00a:b4fa/1282c19:dd:d9:dd:c25:c25a:d00a:b4fa
2522c19:dd:d9:dd:c25:c25a:d00a:b4fb/1282c19:dd:d9:dd:c25:c25a:d00a:b4fb
2532c19:dd:d9:dd:c25:c25a:d00a:b4fc/1282c19:dd:d9:dd:c25:c25a:d00a:b4fc
2542c19:dd:d9:dd:c25:c25a:d00a:b4fd/1282c19:dd:d9:dd:c25:c25a:d00a:b4fd
2552c19:dd:d9:dd:c25:c25a:d00a:b4fe/1282c19:dd:d9:dd:c25:c25a:d00a:b4fe
2562c19:dd:d9:dd:c25:c25a:d00a:b4ff/1282c19:dd:d9:dd:c25:c25a:d00a:b4ff

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.