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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:dd0:ec00:c25:c25:dd3:c400/119
First address
2c19:dd:dd0:ec00:c25:c25:dd3:c400
Last address
2c19:dd:dd0:ec00:c25:c25:dd3:c5ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0dd0:ec00:0c25:0c25:0dd3:c400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
4.c.3.d.d.0.5.2.c.0.5.2.c.0.0.0.c.e.0.d.d.0.d.d.0.0.9.1.c.2.ip6.arpa
5.c.3.d.d.0.5.2.c.0.5.2.c.0.0.0.c.e.0.d.d.0.d.d.0.0.9.1.c.2.ip6.arpa
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:dd0:ec00:c25:c25:dd3:c400/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:dd0:ec00:c25:c25:dd3:c400/1272c19:dd:dd0:ec00:c25:c25:dd3:c401
22c19:dd:dd0:ec00:c25:c25:dd3:c402/1272c19:dd:dd0:ec00:c25:c25:dd3:c403
32c19:dd:dd0:ec00:c25:c25:dd3:c404/1272c19:dd:dd0:ec00:c25:c25:dd3:c405
42c19:dd:dd0:ec00:c25:c25:dd3:c406/1272c19:dd:dd0:ec00:c25:c25:dd3:c407
52c19:dd:dd0:ec00:c25:c25:dd3:c408/1272c19:dd:dd0:ec00:c25:c25:dd3:c409
62c19:dd:dd0:ec00:c25:c25:dd3:c40a/1272c19:dd:dd0:ec00:c25:c25:dd3:c40b
72c19:dd:dd0:ec00:c25:c25:dd3:c40c/1272c19:dd:dd0:ec00:c25:c25:dd3:c40d
82c19:dd:dd0:ec00:c25:c25:dd3:c40e/1272c19:dd:dd0:ec00:c25:c25:dd3:c40f
92c19:dd:dd0:ec00:c25:c25:dd3:c410/1272c19:dd:dd0:ec00:c25:c25:dd3:c411
102c19:dd:dd0:ec00:c25:c25:dd3:c412/1272c19:dd:dd0:ec00:c25:c25:dd3:c413
112c19:dd:dd0:ec00:c25:c25:dd3:c414/1272c19:dd:dd0:ec00:c25:c25:dd3:c415
122c19:dd:dd0:ec00:c25:c25:dd3:c416/1272c19:dd:dd0:ec00:c25:c25:dd3:c417
132c19:dd:dd0:ec00:c25:c25:dd3:c418/1272c19:dd:dd0:ec00:c25:c25:dd3:c419
142c19:dd:dd0:ec00:c25:c25:dd3:c41a/1272c19:dd:dd0:ec00:c25:c25:dd3:c41b
152c19:dd:dd0:ec00:c25:c25:dd3:c41c/1272c19:dd:dd0:ec00:c25:c25:dd3:c41d
162c19:dd:dd0:ec00:c25:c25:dd3:c41e/1272c19:dd:dd0:ec00:c25:c25:dd3:c41f
172c19:dd:dd0:ec00:c25:c25:dd3:c420/1272c19:dd:dd0:ec00:c25:c25:dd3:c421
182c19:dd:dd0:ec00:c25:c25:dd3:c422/1272c19:dd:dd0:ec00:c25:c25:dd3:c423
192c19:dd:dd0:ec00:c25:c25:dd3:c424/1272c19:dd:dd0:ec00:c25:c25:dd3:c425
202c19:dd:dd0:ec00:c25:c25:dd3:c426/1272c19:dd:dd0:ec00:c25:c25:dd3:c427
212c19:dd:dd0:ec00:c25:c25:dd3:c428/1272c19:dd:dd0:ec00:c25:c25:dd3:c429
222c19:dd:dd0:ec00:c25:c25:dd3:c42a/1272c19:dd:dd0:ec00:c25:c25:dd3:c42b
232c19:dd:dd0:ec00:c25:c25:dd3:c42c/1272c19:dd:dd0:ec00:c25:c25:dd3:c42d
242c19:dd:dd0:ec00:c25:c25:dd3:c42e/1272c19:dd:dd0:ec00:c25:c25:dd3:c42f
252c19:dd:dd0:ec00:c25:c25:dd3:c430/1272c19:dd:dd0:ec00:c25:c25:dd3:c431
262c19:dd:dd0:ec00:c25:c25:dd3:c432/1272c19:dd:dd0:ec00:c25:c25:dd3:c433
272c19:dd:dd0:ec00:c25:c25:dd3:c434/1272c19:dd:dd0:ec00:c25:c25:dd3:c435
282c19:dd:dd0:ec00:c25:c25:dd3:c436/1272c19:dd:dd0:ec00:c25:c25:dd3:c437
292c19:dd:dd0:ec00:c25:c25:dd3:c438/1272c19:dd:dd0:ec00:c25:c25:dd3:c439
302c19:dd:dd0:ec00:c25:c25:dd3:c43a/1272c19:dd:dd0:ec00:c25:c25:dd3:c43b
312c19:dd:dd0:ec00:c25:c25:dd3:c43c/1272c19:dd:dd0:ec00:c25:c25:dd3:c43d
322c19:dd:dd0:ec00:c25:c25:dd3:c43e/1272c19:dd:dd0:ec00:c25:c25:dd3:c43f
332c19:dd:dd0:ec00:c25:c25:dd3:c440/1272c19:dd:dd0:ec00:c25:c25:dd3:c441
342c19:dd:dd0:ec00:c25:c25:dd3:c442/1272c19:dd:dd0:ec00:c25:c25:dd3:c443
352c19:dd:dd0:ec00:c25:c25:dd3:c444/1272c19:dd:dd0:ec00:c25:c25:dd3:c445
362c19:dd:dd0:ec00:c25:c25:dd3:c446/1272c19:dd:dd0:ec00:c25:c25:dd3:c447
372c19:dd:dd0:ec00:c25:c25:dd3:c448/1272c19:dd:dd0:ec00:c25:c25:dd3:c449
382c19:dd:dd0:ec00:c25:c25:dd3:c44a/1272c19:dd:dd0:ec00:c25:c25:dd3:c44b
392c19:dd:dd0:ec00:c25:c25:dd3:c44c/1272c19:dd:dd0:ec00:c25:c25:dd3:c44d
402c19:dd:dd0:ec00:c25:c25:dd3:c44e/1272c19:dd:dd0:ec00:c25:c25:dd3:c44f
412c19:dd:dd0:ec00:c25:c25:dd3:c450/1272c19:dd:dd0:ec00:c25:c25:dd3:c451
422c19:dd:dd0:ec00:c25:c25:dd3:c452/1272c19:dd:dd0:ec00:c25:c25:dd3:c453
432c19:dd:dd0:ec00:c25:c25:dd3:c454/1272c19:dd:dd0:ec00:c25:c25:dd3:c455
442c19:dd:dd0:ec00:c25:c25:dd3:c456/1272c19:dd:dd0:ec00:c25:c25:dd3:c457
452c19:dd:dd0:ec00:c25:c25:dd3:c458/1272c19:dd:dd0:ec00:c25:c25:dd3:c459
462c19:dd:dd0:ec00:c25:c25:dd3:c45a/1272c19:dd:dd0:ec00:c25:c25:dd3:c45b
472c19:dd:dd0:ec00:c25:c25:dd3:c45c/1272c19:dd:dd0:ec00:c25:c25:dd3:c45d
482c19:dd:dd0:ec00:c25:c25:dd3:c45e/1272c19:dd:dd0:ec00:c25:c25:dd3:c45f
492c19:dd:dd0:ec00:c25:c25:dd3:c460/1272c19:dd:dd0:ec00:c25:c25:dd3:c461
502c19:dd:dd0:ec00:c25:c25:dd3:c462/1272c19:dd:dd0:ec00:c25:c25:dd3:c463
512c19:dd:dd0:ec00:c25:c25:dd3:c464/1272c19:dd:dd0:ec00:c25:c25:dd3:c465
522c19:dd:dd0:ec00:c25:c25:dd3:c466/1272c19:dd:dd0:ec00:c25:c25:dd3:c467
532c19:dd:dd0:ec00:c25:c25:dd3:c468/1272c19:dd:dd0:ec00:c25:c25:dd3:c469
542c19:dd:dd0:ec00:c25:c25:dd3:c46a/1272c19:dd:dd0:ec00:c25:c25:dd3:c46b
552c19:dd:dd0:ec00:c25:c25:dd3:c46c/1272c19:dd:dd0:ec00:c25:c25:dd3:c46d
562c19:dd:dd0:ec00:c25:c25:dd3:c46e/1272c19:dd:dd0:ec00:c25:c25:dd3:c46f
572c19:dd:dd0:ec00:c25:c25:dd3:c470/1272c19:dd:dd0:ec00:c25:c25:dd3:c471
582c19:dd:dd0:ec00:c25:c25:dd3:c472/1272c19:dd:dd0:ec00:c25:c25:dd3:c473
592c19:dd:dd0:ec00:c25:c25:dd3:c474/1272c19:dd:dd0:ec00:c25:c25:dd3:c475
602c19:dd:dd0:ec00:c25:c25:dd3:c476/1272c19:dd:dd0:ec00:c25:c25:dd3:c477
612c19:dd:dd0:ec00:c25:c25:dd3:c478/1272c19:dd:dd0:ec00:c25:c25:dd3:c479
622c19:dd:dd0:ec00:c25:c25:dd3:c47a/1272c19:dd:dd0:ec00:c25:c25:dd3:c47b
632c19:dd:dd0:ec00:c25:c25:dd3:c47c/1272c19:dd:dd0:ec00:c25:c25:dd3:c47d
642c19:dd:dd0:ec00:c25:c25:dd3:c47e/1272c19:dd:dd0:ec00:c25:c25:dd3:c47f
652c19:dd:dd0:ec00:c25:c25:dd3:c480/1272c19:dd:dd0:ec00:c25:c25:dd3:c481
662c19:dd:dd0:ec00:c25:c25:dd3:c482/1272c19:dd:dd0:ec00:c25:c25:dd3:c483
672c19:dd:dd0:ec00:c25:c25:dd3:c484/1272c19:dd:dd0:ec00:c25:c25:dd3:c485
682c19:dd:dd0:ec00:c25:c25:dd3:c486/1272c19:dd:dd0:ec00:c25:c25:dd3:c487
692c19:dd:dd0:ec00:c25:c25:dd3:c488/1272c19:dd:dd0:ec00:c25:c25:dd3:c489
702c19:dd:dd0:ec00:c25:c25:dd3:c48a/1272c19:dd:dd0:ec00:c25:c25:dd3:c48b
712c19:dd:dd0:ec00:c25:c25:dd3:c48c/1272c19:dd:dd0:ec00:c25:c25:dd3:c48d
722c19:dd:dd0:ec00:c25:c25:dd3:c48e/1272c19:dd:dd0:ec00:c25:c25:dd3:c48f
732c19:dd:dd0:ec00:c25:c25:dd3:c490/1272c19:dd:dd0:ec00:c25:c25:dd3:c491
742c19:dd:dd0:ec00:c25:c25:dd3:c492/1272c19:dd:dd0:ec00:c25:c25:dd3:c493
752c19:dd:dd0:ec00:c25:c25:dd3:c494/1272c19:dd:dd0:ec00:c25:c25:dd3:c495
762c19:dd:dd0:ec00:c25:c25:dd3:c496/1272c19:dd:dd0:ec00:c25:c25:dd3:c497
772c19:dd:dd0:ec00:c25:c25:dd3:c498/1272c19:dd:dd0:ec00:c25:c25:dd3:c499
782c19:dd:dd0:ec00:c25:c25:dd3:c49a/1272c19:dd:dd0:ec00:c25:c25:dd3:c49b
792c19:dd:dd0:ec00:c25:c25:dd3:c49c/1272c19:dd:dd0:ec00:c25:c25:dd3:c49d
802c19:dd:dd0:ec00:c25:c25:dd3:c49e/1272c19:dd:dd0:ec00:c25:c25:dd3:c49f
812c19:dd:dd0:ec00:c25:c25:dd3:c4a0/1272c19:dd:dd0:ec00:c25:c25:dd3:c4a1
822c19:dd:dd0:ec00:c25:c25:dd3:c4a2/1272c19:dd:dd0:ec00:c25:c25:dd3:c4a3
832c19:dd:dd0:ec00:c25:c25:dd3:c4a4/1272c19:dd:dd0:ec00:c25:c25:dd3:c4a5
842c19:dd:dd0:ec00:c25:c25:dd3:c4a6/1272c19:dd:dd0:ec00:c25:c25:dd3:c4a7
852c19:dd:dd0:ec00:c25:c25:dd3:c4a8/1272c19:dd:dd0:ec00:c25:c25:dd3:c4a9
862c19:dd:dd0:ec00:c25:c25:dd3:c4aa/1272c19:dd:dd0:ec00:c25:c25:dd3:c4ab
872c19:dd:dd0:ec00:c25:c25:dd3:c4ac/1272c19:dd:dd0:ec00:c25:c25:dd3:c4ad
882c19:dd:dd0:ec00:c25:c25:dd3:c4ae/1272c19:dd:dd0:ec00:c25:c25:dd3:c4af
892c19:dd:dd0:ec00:c25:c25:dd3:c4b0/1272c19:dd:dd0:ec00:c25:c25:dd3:c4b1
902c19:dd:dd0:ec00:c25:c25:dd3:c4b2/1272c19:dd:dd0:ec00:c25:c25:dd3:c4b3
912c19:dd:dd0:ec00:c25:c25:dd3:c4b4/1272c19:dd:dd0:ec00:c25:c25:dd3:c4b5
922c19:dd:dd0:ec00:c25:c25:dd3:c4b6/1272c19:dd:dd0:ec00:c25:c25:dd3:c4b7
932c19:dd:dd0:ec00:c25:c25:dd3:c4b8/1272c19:dd:dd0:ec00:c25:c25:dd3:c4b9
942c19:dd:dd0:ec00:c25:c25:dd3:c4ba/1272c19:dd:dd0:ec00:c25:c25:dd3:c4bb
952c19:dd:dd0:ec00:c25:c25:dd3:c4bc/1272c19:dd:dd0:ec00:c25:c25:dd3:c4bd
962c19:dd:dd0:ec00:c25:c25:dd3:c4be/1272c19:dd:dd0:ec00:c25:c25:dd3:c4bf
972c19:dd:dd0:ec00:c25:c25:dd3:c4c0/1272c19:dd:dd0:ec00:c25:c25:dd3:c4c1
982c19:dd:dd0:ec00:c25:c25:dd3:c4c2/1272c19:dd:dd0:ec00:c25:c25:dd3:c4c3
992c19:dd:dd0:ec00:c25:c25:dd3:c4c4/1272c19:dd:dd0:ec00:c25:c25:dd3:c4c5
1002c19:dd:dd0:ec00:c25:c25:dd3:c4c6/1272c19:dd:dd0:ec00:c25:c25:dd3:c4c7
1012c19:dd:dd0:ec00:c25:c25:dd3:c4c8/1272c19:dd:dd0:ec00:c25:c25:dd3:c4c9
1022c19:dd:dd0:ec00:c25:c25:dd3:c4ca/1272c19:dd:dd0:ec00:c25:c25:dd3:c4cb
1032c19:dd:dd0:ec00:c25:c25:dd3:c4cc/1272c19:dd:dd0:ec00:c25:c25:dd3:c4cd
1042c19:dd:dd0:ec00:c25:c25:dd3:c4ce/1272c19:dd:dd0:ec00:c25:c25:dd3:c4cf
1052c19:dd:dd0:ec00:c25:c25:dd3:c4d0/1272c19:dd:dd0:ec00:c25:c25:dd3:c4d1
1062c19:dd:dd0:ec00:c25:c25:dd3:c4d2/1272c19:dd:dd0:ec00:c25:c25:dd3:c4d3
1072c19:dd:dd0:ec00:c25:c25:dd3:c4d4/1272c19:dd:dd0:ec00:c25:c25:dd3:c4d5
1082c19:dd:dd0:ec00:c25:c25:dd3:c4d6/1272c19:dd:dd0:ec00:c25:c25:dd3:c4d7
1092c19:dd:dd0:ec00:c25:c25:dd3:c4d8/1272c19:dd:dd0:ec00:c25:c25:dd3:c4d9
1102c19:dd:dd0:ec00:c25:c25:dd3:c4da/1272c19:dd:dd0:ec00:c25:c25:dd3:c4db
1112c19:dd:dd0:ec00:c25:c25:dd3:c4dc/1272c19:dd:dd0:ec00:c25:c25:dd3:c4dd
1122c19:dd:dd0:ec00:c25:c25:dd3:c4de/1272c19:dd:dd0:ec00:c25:c25:dd3:c4df
1132c19:dd:dd0:ec00:c25:c25:dd3:c4e0/1272c19:dd:dd0:ec00:c25:c25:dd3:c4e1
1142c19:dd:dd0:ec00:c25:c25:dd3:c4e2/1272c19:dd:dd0:ec00:c25:c25:dd3:c4e3
1152c19:dd:dd0:ec00:c25:c25:dd3:c4e4/1272c19:dd:dd0:ec00:c25:c25:dd3:c4e5
1162c19:dd:dd0:ec00:c25:c25:dd3:c4e6/1272c19:dd:dd0:ec00:c25:c25:dd3:c4e7
1172c19:dd:dd0:ec00:c25:c25:dd3:c4e8/1272c19:dd:dd0:ec00:c25:c25:dd3:c4e9
1182c19:dd:dd0:ec00:c25:c25:dd3:c4ea/1272c19:dd:dd0:ec00:c25:c25:dd3:c4eb
1192c19:dd:dd0:ec00:c25:c25:dd3:c4ec/1272c19:dd:dd0:ec00:c25:c25:dd3:c4ed
1202c19:dd:dd0:ec00:c25:c25:dd3:c4ee/1272c19:dd:dd0:ec00:c25:c25:dd3:c4ef
1212c19:dd:dd0:ec00:c25:c25:dd3:c4f0/1272c19:dd:dd0:ec00:c25:c25:dd3:c4f1
1222c19:dd:dd0:ec00:c25:c25:dd3:c4f2/1272c19:dd:dd0:ec00:c25:c25:dd3:c4f3
1232c19:dd:dd0:ec00:c25:c25:dd3:c4f4/1272c19:dd:dd0:ec00:c25:c25:dd3:c4f5
1242c19:dd:dd0:ec00:c25:c25:dd3:c4f6/1272c19:dd:dd0:ec00:c25:c25:dd3:c4f7
1252c19:dd:dd0:ec00:c25:c25:dd3:c4f8/1272c19:dd:dd0:ec00:c25:c25:dd3:c4f9
1262c19:dd:dd0:ec00:c25:c25:dd3:c4fa/1272c19:dd:dd0:ec00:c25:c25:dd3:c4fb
1272c19:dd:dd0:ec00:c25:c25:dd3:c4fc/1272c19:dd:dd0:ec00:c25:c25:dd3:c4fd
1282c19:dd:dd0:ec00:c25:c25:dd3:c4fe/1272c19:dd:dd0:ec00:c25:c25:dd3:c4ff
1292c19:dd:dd0:ec00:c25:c25:dd3:c500/1272c19:dd:dd0:ec00:c25:c25:dd3:c501
1302c19:dd:dd0:ec00:c25:c25:dd3:c502/1272c19:dd:dd0:ec00:c25:c25:dd3:c503
1312c19:dd:dd0:ec00:c25:c25:dd3:c504/1272c19:dd:dd0:ec00:c25:c25:dd3:c505
1322c19:dd:dd0:ec00:c25:c25:dd3:c506/1272c19:dd:dd0:ec00:c25:c25:dd3:c507
1332c19:dd:dd0:ec00:c25:c25:dd3:c508/1272c19:dd:dd0:ec00:c25:c25:dd3:c509
1342c19:dd:dd0:ec00:c25:c25:dd3:c50a/1272c19:dd:dd0:ec00:c25:c25:dd3:c50b
1352c19:dd:dd0:ec00:c25:c25:dd3:c50c/1272c19:dd:dd0:ec00:c25:c25:dd3:c50d
1362c19:dd:dd0:ec00:c25:c25:dd3:c50e/1272c19:dd:dd0:ec00:c25:c25:dd3:c50f
1372c19:dd:dd0:ec00:c25:c25:dd3:c510/1272c19:dd:dd0:ec00:c25:c25:dd3:c511
1382c19:dd:dd0:ec00:c25:c25:dd3:c512/1272c19:dd:dd0:ec00:c25:c25:dd3:c513
1392c19:dd:dd0:ec00:c25:c25:dd3:c514/1272c19:dd:dd0:ec00:c25:c25:dd3:c515
1402c19:dd:dd0:ec00:c25:c25:dd3:c516/1272c19:dd:dd0:ec00:c25:c25:dd3:c517
1412c19:dd:dd0:ec00:c25:c25:dd3:c518/1272c19:dd:dd0:ec00:c25:c25:dd3:c519
1422c19:dd:dd0:ec00:c25:c25:dd3:c51a/1272c19:dd:dd0:ec00:c25:c25:dd3:c51b
1432c19:dd:dd0:ec00:c25:c25:dd3:c51c/1272c19:dd:dd0:ec00:c25:c25:dd3:c51d
1442c19:dd:dd0:ec00:c25:c25:dd3:c51e/1272c19:dd:dd0:ec00:c25:c25:dd3:c51f
1452c19:dd:dd0:ec00:c25:c25:dd3:c520/1272c19:dd:dd0:ec00:c25:c25:dd3:c521
1462c19:dd:dd0:ec00:c25:c25:dd3:c522/1272c19:dd:dd0:ec00:c25:c25:dd3:c523
1472c19:dd:dd0:ec00:c25:c25:dd3:c524/1272c19:dd:dd0:ec00:c25:c25:dd3:c525
1482c19:dd:dd0:ec00:c25:c25:dd3:c526/1272c19:dd:dd0:ec00:c25:c25:dd3:c527
1492c19:dd:dd0:ec00:c25:c25:dd3:c528/1272c19:dd:dd0:ec00:c25:c25:dd3:c529
1502c19:dd:dd0:ec00:c25:c25:dd3:c52a/1272c19:dd:dd0:ec00:c25:c25:dd3:c52b
1512c19:dd:dd0:ec00:c25:c25:dd3:c52c/1272c19:dd:dd0:ec00:c25:c25:dd3:c52d
1522c19:dd:dd0:ec00:c25:c25:dd3:c52e/1272c19:dd:dd0:ec00:c25:c25:dd3:c52f
1532c19:dd:dd0:ec00:c25:c25:dd3:c530/1272c19:dd:dd0:ec00:c25:c25:dd3:c531
1542c19:dd:dd0:ec00:c25:c25:dd3:c532/1272c19:dd:dd0:ec00:c25:c25:dd3:c533
1552c19:dd:dd0:ec00:c25:c25:dd3:c534/1272c19:dd:dd0:ec00:c25:c25:dd3:c535
1562c19:dd:dd0:ec00:c25:c25:dd3:c536/1272c19:dd:dd0:ec00:c25:c25:dd3:c537
1572c19:dd:dd0:ec00:c25:c25:dd3:c538/1272c19:dd:dd0:ec00:c25:c25:dd3:c539
1582c19:dd:dd0:ec00:c25:c25:dd3:c53a/1272c19:dd:dd0:ec00:c25:c25:dd3:c53b
1592c19:dd:dd0:ec00:c25:c25:dd3:c53c/1272c19:dd:dd0:ec00:c25:c25:dd3:c53d
1602c19:dd:dd0:ec00:c25:c25:dd3:c53e/1272c19:dd:dd0:ec00:c25:c25:dd3:c53f
1612c19:dd:dd0:ec00:c25:c25:dd3:c540/1272c19:dd:dd0:ec00:c25:c25:dd3:c541
1622c19:dd:dd0:ec00:c25:c25:dd3:c542/1272c19:dd:dd0:ec00:c25:c25:dd3:c543
1632c19:dd:dd0:ec00:c25:c25:dd3:c544/1272c19:dd:dd0:ec00:c25:c25:dd3:c545
1642c19:dd:dd0:ec00:c25:c25:dd3:c546/1272c19:dd:dd0:ec00:c25:c25:dd3:c547
1652c19:dd:dd0:ec00:c25:c25:dd3:c548/1272c19:dd:dd0:ec00:c25:c25:dd3:c549
1662c19:dd:dd0:ec00:c25:c25:dd3:c54a/1272c19:dd:dd0:ec00:c25:c25:dd3:c54b
1672c19:dd:dd0:ec00:c25:c25:dd3:c54c/1272c19:dd:dd0:ec00:c25:c25:dd3:c54d
1682c19:dd:dd0:ec00:c25:c25:dd3:c54e/1272c19:dd:dd0:ec00:c25:c25:dd3:c54f
1692c19:dd:dd0:ec00:c25:c25:dd3:c550/1272c19:dd:dd0:ec00:c25:c25:dd3:c551
1702c19:dd:dd0:ec00:c25:c25:dd3:c552/1272c19:dd:dd0:ec00:c25:c25:dd3:c553
1712c19:dd:dd0:ec00:c25:c25:dd3:c554/1272c19:dd:dd0:ec00:c25:c25:dd3:c555
1722c19:dd:dd0:ec00:c25:c25:dd3:c556/1272c19:dd:dd0:ec00:c25:c25:dd3:c557
1732c19:dd:dd0:ec00:c25:c25:dd3:c558/1272c19:dd:dd0:ec00:c25:c25:dd3:c559
1742c19:dd:dd0:ec00:c25:c25:dd3:c55a/1272c19:dd:dd0:ec00:c25:c25:dd3:c55b
1752c19:dd:dd0:ec00:c25:c25:dd3:c55c/1272c19:dd:dd0:ec00:c25:c25:dd3:c55d
1762c19:dd:dd0:ec00:c25:c25:dd3:c55e/1272c19:dd:dd0:ec00:c25:c25:dd3:c55f
1772c19:dd:dd0:ec00:c25:c25:dd3:c560/1272c19:dd:dd0:ec00:c25:c25:dd3:c561
1782c19:dd:dd0:ec00:c25:c25:dd3:c562/1272c19:dd:dd0:ec00:c25:c25:dd3:c563
1792c19:dd:dd0:ec00:c25:c25:dd3:c564/1272c19:dd:dd0:ec00:c25:c25:dd3:c565
1802c19:dd:dd0:ec00:c25:c25:dd3:c566/1272c19:dd:dd0:ec00:c25:c25:dd3:c567
1812c19:dd:dd0:ec00:c25:c25:dd3:c568/1272c19:dd:dd0:ec00:c25:c25:dd3:c569
1822c19:dd:dd0:ec00:c25:c25:dd3:c56a/1272c19:dd:dd0:ec00:c25:c25:dd3:c56b
1832c19:dd:dd0:ec00:c25:c25:dd3:c56c/1272c19:dd:dd0:ec00:c25:c25:dd3:c56d
1842c19:dd:dd0:ec00:c25:c25:dd3:c56e/1272c19:dd:dd0:ec00:c25:c25:dd3:c56f
1852c19:dd:dd0:ec00:c25:c25:dd3:c570/1272c19:dd:dd0:ec00:c25:c25:dd3:c571
1862c19:dd:dd0:ec00:c25:c25:dd3:c572/1272c19:dd:dd0:ec00:c25:c25:dd3:c573
1872c19:dd:dd0:ec00:c25:c25:dd3:c574/1272c19:dd:dd0:ec00:c25:c25:dd3:c575
1882c19:dd:dd0:ec00:c25:c25:dd3:c576/1272c19:dd:dd0:ec00:c25:c25:dd3:c577
1892c19:dd:dd0:ec00:c25:c25:dd3:c578/1272c19:dd:dd0:ec00:c25:c25:dd3:c579
1902c19:dd:dd0:ec00:c25:c25:dd3:c57a/1272c19:dd:dd0:ec00:c25:c25:dd3:c57b
1912c19:dd:dd0:ec00:c25:c25:dd3:c57c/1272c19:dd:dd0:ec00:c25:c25:dd3:c57d
1922c19:dd:dd0:ec00:c25:c25:dd3:c57e/1272c19:dd:dd0:ec00:c25:c25:dd3:c57f
1932c19:dd:dd0:ec00:c25:c25:dd3:c580/1272c19:dd:dd0:ec00:c25:c25:dd3:c581
1942c19:dd:dd0:ec00:c25:c25:dd3:c582/1272c19:dd:dd0:ec00:c25:c25:dd3:c583
1952c19:dd:dd0:ec00:c25:c25:dd3:c584/1272c19:dd:dd0:ec00:c25:c25:dd3:c585
1962c19:dd:dd0:ec00:c25:c25:dd3:c586/1272c19:dd:dd0:ec00:c25:c25:dd3:c587
1972c19:dd:dd0:ec00:c25:c25:dd3:c588/1272c19:dd:dd0:ec00:c25:c25:dd3:c589
1982c19:dd:dd0:ec00:c25:c25:dd3:c58a/1272c19:dd:dd0:ec00:c25:c25:dd3:c58b
1992c19:dd:dd0:ec00:c25:c25:dd3:c58c/1272c19:dd:dd0:ec00:c25:c25:dd3:c58d
2002c19:dd:dd0:ec00:c25:c25:dd3:c58e/1272c19:dd:dd0:ec00:c25:c25:dd3:c58f
2012c19:dd:dd0:ec00:c25:c25:dd3:c590/1272c19:dd:dd0:ec00:c25:c25:dd3:c591
2022c19:dd:dd0:ec00:c25:c25:dd3:c592/1272c19:dd:dd0:ec00:c25:c25:dd3:c593
2032c19:dd:dd0:ec00:c25:c25:dd3:c594/1272c19:dd:dd0:ec00:c25:c25:dd3:c595
2042c19:dd:dd0:ec00:c25:c25:dd3:c596/1272c19:dd:dd0:ec00:c25:c25:dd3:c597
2052c19:dd:dd0:ec00:c25:c25:dd3:c598/1272c19:dd:dd0:ec00:c25:c25:dd3:c599
2062c19:dd:dd0:ec00:c25:c25:dd3:c59a/1272c19:dd:dd0:ec00:c25:c25:dd3:c59b
2072c19:dd:dd0:ec00:c25:c25:dd3:c59c/1272c19:dd:dd0:ec00:c25:c25:dd3:c59d
2082c19:dd:dd0:ec00:c25:c25:dd3:c59e/1272c19:dd:dd0:ec00:c25:c25:dd3:c59f
2092c19:dd:dd0:ec00:c25:c25:dd3:c5a0/1272c19:dd:dd0:ec00:c25:c25:dd3:c5a1
2102c19:dd:dd0:ec00:c25:c25:dd3:c5a2/1272c19:dd:dd0:ec00:c25:c25:dd3:c5a3
2112c19:dd:dd0:ec00:c25:c25:dd3:c5a4/1272c19:dd:dd0:ec00:c25:c25:dd3:c5a5
2122c19:dd:dd0:ec00:c25:c25:dd3:c5a6/1272c19:dd:dd0:ec00:c25:c25:dd3:c5a7
2132c19:dd:dd0:ec00:c25:c25:dd3:c5a8/1272c19:dd:dd0:ec00:c25:c25:dd3:c5a9
2142c19:dd:dd0:ec00:c25:c25:dd3:c5aa/1272c19:dd:dd0:ec00:c25:c25:dd3:c5ab
2152c19:dd:dd0:ec00:c25:c25:dd3:c5ac/1272c19:dd:dd0:ec00:c25:c25:dd3:c5ad
2162c19:dd:dd0:ec00:c25:c25:dd3:c5ae/1272c19:dd:dd0:ec00:c25:c25:dd3:c5af
2172c19:dd:dd0:ec00:c25:c25:dd3:c5b0/1272c19:dd:dd0:ec00:c25:c25:dd3:c5b1
2182c19:dd:dd0:ec00:c25:c25:dd3:c5b2/1272c19:dd:dd0:ec00:c25:c25:dd3:c5b3
2192c19:dd:dd0:ec00:c25:c25:dd3:c5b4/1272c19:dd:dd0:ec00:c25:c25:dd3:c5b5
2202c19:dd:dd0:ec00:c25:c25:dd3:c5b6/1272c19:dd:dd0:ec00:c25:c25:dd3:c5b7
2212c19:dd:dd0:ec00:c25:c25:dd3:c5b8/1272c19:dd:dd0:ec00:c25:c25:dd3:c5b9
2222c19:dd:dd0:ec00:c25:c25:dd3:c5ba/1272c19:dd:dd0:ec00:c25:c25:dd3:c5bb
2232c19:dd:dd0:ec00:c25:c25:dd3:c5bc/1272c19:dd:dd0:ec00:c25:c25:dd3:c5bd
2242c19:dd:dd0:ec00:c25:c25:dd3:c5be/1272c19:dd:dd0:ec00:c25:c25:dd3:c5bf
2252c19:dd:dd0:ec00:c25:c25:dd3:c5c0/1272c19:dd:dd0:ec00:c25:c25:dd3:c5c1
2262c19:dd:dd0:ec00:c25:c25:dd3:c5c2/1272c19:dd:dd0:ec00:c25:c25:dd3:c5c3
2272c19:dd:dd0:ec00:c25:c25:dd3:c5c4/1272c19:dd:dd0:ec00:c25:c25:dd3:c5c5
2282c19:dd:dd0:ec00:c25:c25:dd3:c5c6/1272c19:dd:dd0:ec00:c25:c25:dd3:c5c7
2292c19:dd:dd0:ec00:c25:c25:dd3:c5c8/1272c19:dd:dd0:ec00:c25:c25:dd3:c5c9
2302c19:dd:dd0:ec00:c25:c25:dd3:c5ca/1272c19:dd:dd0:ec00:c25:c25:dd3:c5cb
2312c19:dd:dd0:ec00:c25:c25:dd3:c5cc/1272c19:dd:dd0:ec00:c25:c25:dd3:c5cd
2322c19:dd:dd0:ec00:c25:c25:dd3:c5ce/1272c19:dd:dd0:ec00:c25:c25:dd3:c5cf
2332c19:dd:dd0:ec00:c25:c25:dd3:c5d0/1272c19:dd:dd0:ec00:c25:c25:dd3:c5d1
2342c19:dd:dd0:ec00:c25:c25:dd3:c5d2/1272c19:dd:dd0:ec00:c25:c25:dd3:c5d3
2352c19:dd:dd0:ec00:c25:c25:dd3:c5d4/1272c19:dd:dd0:ec00:c25:c25:dd3:c5d5
2362c19:dd:dd0:ec00:c25:c25:dd3:c5d6/1272c19:dd:dd0:ec00:c25:c25:dd3:c5d7
2372c19:dd:dd0:ec00:c25:c25:dd3:c5d8/1272c19:dd:dd0:ec00:c25:c25:dd3:c5d9
2382c19:dd:dd0:ec00:c25:c25:dd3:c5da/1272c19:dd:dd0:ec00:c25:c25:dd3:c5db
2392c19:dd:dd0:ec00:c25:c25:dd3:c5dc/1272c19:dd:dd0:ec00:c25:c25:dd3:c5dd
2402c19:dd:dd0:ec00:c25:c25:dd3:c5de/1272c19:dd:dd0:ec00:c25:c25:dd3:c5df
2412c19:dd:dd0:ec00:c25:c25:dd3:c5e0/1272c19:dd:dd0:ec00:c25:c25:dd3:c5e1
2422c19:dd:dd0:ec00:c25:c25:dd3:c5e2/1272c19:dd:dd0:ec00:c25:c25:dd3:c5e3
2432c19:dd:dd0:ec00:c25:c25:dd3:c5e4/1272c19:dd:dd0:ec00:c25:c25:dd3:c5e5
2442c19:dd:dd0:ec00:c25:c25:dd3:c5e6/1272c19:dd:dd0:ec00:c25:c25:dd3:c5e7
2452c19:dd:dd0:ec00:c25:c25:dd3:c5e8/1272c19:dd:dd0:ec00:c25:c25:dd3:c5e9
2462c19:dd:dd0:ec00:c25:c25:dd3:c5ea/1272c19:dd:dd0:ec00:c25:c25:dd3:c5eb
2472c19:dd:dd0:ec00:c25:c25:dd3:c5ec/1272c19:dd:dd0:ec00:c25:c25:dd3:c5ed
2482c19:dd:dd0:ec00:c25:c25:dd3:c5ee/1272c19:dd:dd0:ec00:c25:c25:dd3:c5ef
2492c19:dd:dd0:ec00:c25:c25:dd3:c5f0/1272c19:dd:dd0:ec00:c25:c25:dd3:c5f1
2502c19:dd:dd0:ec00:c25:c25:dd3:c5f2/1272c19:dd:dd0:ec00:c25:c25:dd3:c5f3
2512c19:dd:dd0:ec00:c25:c25:dd3:c5f4/1272c19:dd:dd0:ec00:c25:c25:dd3:c5f5
2522c19:dd:dd0:ec00:c25:c25:dd3:c5f6/1272c19:dd:dd0:ec00:c25:c25:dd3:c5f7
2532c19:dd:dd0:ec00:c25:c25:dd3:c5f8/1272c19:dd:dd0:ec00:c25:c25:dd3:c5f9
2542c19:dd:dd0:ec00:c25:c25:dd3:c5fa/1272c19:dd:dd0:ec00:c25:c25:dd3:c5fb
2552c19:dd:dd0:ec00:c25:c25:dd3:c5fc/1272c19:dd:dd0:ec00:c25:c25:dd3:c5fd
2562c19:dd:dd0:ec00:c25:c25:dd3:c5fe/1272c19:dd:dd0:ec00:c25:c25:dd3:c5ff

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.