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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:d9:dd:c25:c25:94de:e400/119
First address
2c19:dd:d9:dd:c25:c25:94de:e400
Last address
2c19:dd:d9:dd:c25:c25:94de:e5ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:e400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
4.e.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
5.e.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
/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:d9:dd:c25:c25:94de:e400/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:e400/1272c19:dd:d9:dd:c25:c25:94de:e401
22c19:dd:d9:dd:c25:c25:94de:e402/1272c19:dd:d9:dd:c25:c25:94de:e403
32c19:dd:d9:dd:c25:c25:94de:e404/1272c19:dd:d9:dd:c25:c25:94de:e405
42c19:dd:d9:dd:c25:c25:94de:e406/1272c19:dd:d9:dd:c25:c25:94de:e407
52c19:dd:d9:dd:c25:c25:94de:e408/1272c19:dd:d9:dd:c25:c25:94de:e409
62c19:dd:d9:dd:c25:c25:94de:e40a/1272c19:dd:d9:dd:c25:c25:94de:e40b
72c19:dd:d9:dd:c25:c25:94de:e40c/1272c19:dd:d9:dd:c25:c25:94de:e40d
82c19:dd:d9:dd:c25:c25:94de:e40e/1272c19:dd:d9:dd:c25:c25:94de:e40f
92c19:dd:d9:dd:c25:c25:94de:e410/1272c19:dd:d9:dd:c25:c25:94de:e411
102c19:dd:d9:dd:c25:c25:94de:e412/1272c19:dd:d9:dd:c25:c25:94de:e413
112c19:dd:d9:dd:c25:c25:94de:e414/1272c19:dd:d9:dd:c25:c25:94de:e415
122c19:dd:d9:dd:c25:c25:94de:e416/1272c19:dd:d9:dd:c25:c25:94de:e417
132c19:dd:d9:dd:c25:c25:94de:e418/1272c19:dd:d9:dd:c25:c25:94de:e419
142c19:dd:d9:dd:c25:c25:94de:e41a/1272c19:dd:d9:dd:c25:c25:94de:e41b
152c19:dd:d9:dd:c25:c25:94de:e41c/1272c19:dd:d9:dd:c25:c25:94de:e41d
162c19:dd:d9:dd:c25:c25:94de:e41e/1272c19:dd:d9:dd:c25:c25:94de:e41f
172c19:dd:d9:dd:c25:c25:94de:e420/1272c19:dd:d9:dd:c25:c25:94de:e421
182c19:dd:d9:dd:c25:c25:94de:e422/1272c19:dd:d9:dd:c25:c25:94de:e423
192c19:dd:d9:dd:c25:c25:94de:e424/1272c19:dd:d9:dd:c25:c25:94de:e425
202c19:dd:d9:dd:c25:c25:94de:e426/1272c19:dd:d9:dd:c25:c25:94de:e427
212c19:dd:d9:dd:c25:c25:94de:e428/1272c19:dd:d9:dd:c25:c25:94de:e429
222c19:dd:d9:dd:c25:c25:94de:e42a/1272c19:dd:d9:dd:c25:c25:94de:e42b
232c19:dd:d9:dd:c25:c25:94de:e42c/1272c19:dd:d9:dd:c25:c25:94de:e42d
242c19:dd:d9:dd:c25:c25:94de:e42e/1272c19:dd:d9:dd:c25:c25:94de:e42f
252c19:dd:d9:dd:c25:c25:94de:e430/1272c19:dd:d9:dd:c25:c25:94de:e431
262c19:dd:d9:dd:c25:c25:94de:e432/1272c19:dd:d9:dd:c25:c25:94de:e433
272c19:dd:d9:dd:c25:c25:94de:e434/1272c19:dd:d9:dd:c25:c25:94de:e435
282c19:dd:d9:dd:c25:c25:94de:e436/1272c19:dd:d9:dd:c25:c25:94de:e437
292c19:dd:d9:dd:c25:c25:94de:e438/1272c19:dd:d9:dd:c25:c25:94de:e439
302c19:dd:d9:dd:c25:c25:94de:e43a/1272c19:dd:d9:dd:c25:c25:94de:e43b
312c19:dd:d9:dd:c25:c25:94de:e43c/1272c19:dd:d9:dd:c25:c25:94de:e43d
322c19:dd:d9:dd:c25:c25:94de:e43e/1272c19:dd:d9:dd:c25:c25:94de:e43f
332c19:dd:d9:dd:c25:c25:94de:e440/1272c19:dd:d9:dd:c25:c25:94de:e441
342c19:dd:d9:dd:c25:c25:94de:e442/1272c19:dd:d9:dd:c25:c25:94de:e443
352c19:dd:d9:dd:c25:c25:94de:e444/1272c19:dd:d9:dd:c25:c25:94de:e445
362c19:dd:d9:dd:c25:c25:94de:e446/1272c19:dd:d9:dd:c25:c25:94de:e447
372c19:dd:d9:dd:c25:c25:94de:e448/1272c19:dd:d9:dd:c25:c25:94de:e449
382c19:dd:d9:dd:c25:c25:94de:e44a/1272c19:dd:d9:dd:c25:c25:94de:e44b
392c19:dd:d9:dd:c25:c25:94de:e44c/1272c19:dd:d9:dd:c25:c25:94de:e44d
402c19:dd:d9:dd:c25:c25:94de:e44e/1272c19:dd:d9:dd:c25:c25:94de:e44f
412c19:dd:d9:dd:c25:c25:94de:e450/1272c19:dd:d9:dd:c25:c25:94de:e451
422c19:dd:d9:dd:c25:c25:94de:e452/1272c19:dd:d9:dd:c25:c25:94de:e453
432c19:dd:d9:dd:c25:c25:94de:e454/1272c19:dd:d9:dd:c25:c25:94de:e455
442c19:dd:d9:dd:c25:c25:94de:e456/1272c19:dd:d9:dd:c25:c25:94de:e457
452c19:dd:d9:dd:c25:c25:94de:e458/1272c19:dd:d9:dd:c25:c25:94de:e459
462c19:dd:d9:dd:c25:c25:94de:e45a/1272c19:dd:d9:dd:c25:c25:94de:e45b
472c19:dd:d9:dd:c25:c25:94de:e45c/1272c19:dd:d9:dd:c25:c25:94de:e45d
482c19:dd:d9:dd:c25:c25:94de:e45e/1272c19:dd:d9:dd:c25:c25:94de:e45f
492c19:dd:d9:dd:c25:c25:94de:e460/1272c19:dd:d9:dd:c25:c25:94de:e461
502c19:dd:d9:dd:c25:c25:94de:e462/1272c19:dd:d9:dd:c25:c25:94de:e463
512c19:dd:d9:dd:c25:c25:94de:e464/1272c19:dd:d9:dd:c25:c25:94de:e465
522c19:dd:d9:dd:c25:c25:94de:e466/1272c19:dd:d9:dd:c25:c25:94de:e467
532c19:dd:d9:dd:c25:c25:94de:e468/1272c19:dd:d9:dd:c25:c25:94de:e469
542c19:dd:d9:dd:c25:c25:94de:e46a/1272c19:dd:d9:dd:c25:c25:94de:e46b
552c19:dd:d9:dd:c25:c25:94de:e46c/1272c19:dd:d9:dd:c25:c25:94de:e46d
562c19:dd:d9:dd:c25:c25:94de:e46e/1272c19:dd:d9:dd:c25:c25:94de:e46f
572c19:dd:d9:dd:c25:c25:94de:e470/1272c19:dd:d9:dd:c25:c25:94de:e471
582c19:dd:d9:dd:c25:c25:94de:e472/1272c19:dd:d9:dd:c25:c25:94de:e473
592c19:dd:d9:dd:c25:c25:94de:e474/1272c19:dd:d9:dd:c25:c25:94de:e475
602c19:dd:d9:dd:c25:c25:94de:e476/1272c19:dd:d9:dd:c25:c25:94de:e477
612c19:dd:d9:dd:c25:c25:94de:e478/1272c19:dd:d9:dd:c25:c25:94de:e479
622c19:dd:d9:dd:c25:c25:94de:e47a/1272c19:dd:d9:dd:c25:c25:94de:e47b
632c19:dd:d9:dd:c25:c25:94de:e47c/1272c19:dd:d9:dd:c25:c25:94de:e47d
642c19:dd:d9:dd:c25:c25:94de:e47e/1272c19:dd:d9:dd:c25:c25:94de:e47f
652c19:dd:d9:dd:c25:c25:94de:e480/1272c19:dd:d9:dd:c25:c25:94de:e481
662c19:dd:d9:dd:c25:c25:94de:e482/1272c19:dd:d9:dd:c25:c25:94de:e483
672c19:dd:d9:dd:c25:c25:94de:e484/1272c19:dd:d9:dd:c25:c25:94de:e485
682c19:dd:d9:dd:c25:c25:94de:e486/1272c19:dd:d9:dd:c25:c25:94de:e487
692c19:dd:d9:dd:c25:c25:94de:e488/1272c19:dd:d9:dd:c25:c25:94de:e489
702c19:dd:d9:dd:c25:c25:94de:e48a/1272c19:dd:d9:dd:c25:c25:94de:e48b
712c19:dd:d9:dd:c25:c25:94de:e48c/1272c19:dd:d9:dd:c25:c25:94de:e48d
722c19:dd:d9:dd:c25:c25:94de:e48e/1272c19:dd:d9:dd:c25:c25:94de:e48f
732c19:dd:d9:dd:c25:c25:94de:e490/1272c19:dd:d9:dd:c25:c25:94de:e491
742c19:dd:d9:dd:c25:c25:94de:e492/1272c19:dd:d9:dd:c25:c25:94de:e493
752c19:dd:d9:dd:c25:c25:94de:e494/1272c19:dd:d9:dd:c25:c25:94de:e495
762c19:dd:d9:dd:c25:c25:94de:e496/1272c19:dd:d9:dd:c25:c25:94de:e497
772c19:dd:d9:dd:c25:c25:94de:e498/1272c19:dd:d9:dd:c25:c25:94de:e499
782c19:dd:d9:dd:c25:c25:94de:e49a/1272c19:dd:d9:dd:c25:c25:94de:e49b
792c19:dd:d9:dd:c25:c25:94de:e49c/1272c19:dd:d9:dd:c25:c25:94de:e49d
802c19:dd:d9:dd:c25:c25:94de:e49e/1272c19:dd:d9:dd:c25:c25:94de:e49f
812c19:dd:d9:dd:c25:c25:94de:e4a0/1272c19:dd:d9:dd:c25:c25:94de:e4a1
822c19:dd:d9:dd:c25:c25:94de:e4a2/1272c19:dd:d9:dd:c25:c25:94de:e4a3
832c19:dd:d9:dd:c25:c25:94de:e4a4/1272c19:dd:d9:dd:c25:c25:94de:e4a5
842c19:dd:d9:dd:c25:c25:94de:e4a6/1272c19:dd:d9:dd:c25:c25:94de:e4a7
852c19:dd:d9:dd:c25:c25:94de:e4a8/1272c19:dd:d9:dd:c25:c25:94de:e4a9
862c19:dd:d9:dd:c25:c25:94de:e4aa/1272c19:dd:d9:dd:c25:c25:94de:e4ab
872c19:dd:d9:dd:c25:c25:94de:e4ac/1272c19:dd:d9:dd:c25:c25:94de:e4ad
882c19:dd:d9:dd:c25:c25:94de:e4ae/1272c19:dd:d9:dd:c25:c25:94de:e4af
892c19:dd:d9:dd:c25:c25:94de:e4b0/1272c19:dd:d9:dd:c25:c25:94de:e4b1
902c19:dd:d9:dd:c25:c25:94de:e4b2/1272c19:dd:d9:dd:c25:c25:94de:e4b3
912c19:dd:d9:dd:c25:c25:94de:e4b4/1272c19:dd:d9:dd:c25:c25:94de:e4b5
922c19:dd:d9:dd:c25:c25:94de:e4b6/1272c19:dd:d9:dd:c25:c25:94de:e4b7
932c19:dd:d9:dd:c25:c25:94de:e4b8/1272c19:dd:d9:dd:c25:c25:94de:e4b9
942c19:dd:d9:dd:c25:c25:94de:e4ba/1272c19:dd:d9:dd:c25:c25:94de:e4bb
952c19:dd:d9:dd:c25:c25:94de:e4bc/1272c19:dd:d9:dd:c25:c25:94de:e4bd
962c19:dd:d9:dd:c25:c25:94de:e4be/1272c19:dd:d9:dd:c25:c25:94de:e4bf
972c19:dd:d9:dd:c25:c25:94de:e4c0/1272c19:dd:d9:dd:c25:c25:94de:e4c1
982c19:dd:d9:dd:c25:c25:94de:e4c2/1272c19:dd:d9:dd:c25:c25:94de:e4c3
992c19:dd:d9:dd:c25:c25:94de:e4c4/1272c19:dd:d9:dd:c25:c25:94de:e4c5
1002c19:dd:d9:dd:c25:c25:94de:e4c6/1272c19:dd:d9:dd:c25:c25:94de:e4c7
1012c19:dd:d9:dd:c25:c25:94de:e4c8/1272c19:dd:d9:dd:c25:c25:94de:e4c9
1022c19:dd:d9:dd:c25:c25:94de:e4ca/1272c19:dd:d9:dd:c25:c25:94de:e4cb
1032c19:dd:d9:dd:c25:c25:94de:e4cc/1272c19:dd:d9:dd:c25:c25:94de:e4cd
1042c19:dd:d9:dd:c25:c25:94de:e4ce/1272c19:dd:d9:dd:c25:c25:94de:e4cf
1052c19:dd:d9:dd:c25:c25:94de:e4d0/1272c19:dd:d9:dd:c25:c25:94de:e4d1
1062c19:dd:d9:dd:c25:c25:94de:e4d2/1272c19:dd:d9:dd:c25:c25:94de:e4d3
1072c19:dd:d9:dd:c25:c25:94de:e4d4/1272c19:dd:d9:dd:c25:c25:94de:e4d5
1082c19:dd:d9:dd:c25:c25:94de:e4d6/1272c19:dd:d9:dd:c25:c25:94de:e4d7
1092c19:dd:d9:dd:c25:c25:94de:e4d8/1272c19:dd:d9:dd:c25:c25:94de:e4d9
1102c19:dd:d9:dd:c25:c25:94de:e4da/1272c19:dd:d9:dd:c25:c25:94de:e4db
1112c19:dd:d9:dd:c25:c25:94de:e4dc/1272c19:dd:d9:dd:c25:c25:94de:e4dd
1122c19:dd:d9:dd:c25:c25:94de:e4de/1272c19:dd:d9:dd:c25:c25:94de:e4df
1132c19:dd:d9:dd:c25:c25:94de:e4e0/1272c19:dd:d9:dd:c25:c25:94de:e4e1
1142c19:dd:d9:dd:c25:c25:94de:e4e2/1272c19:dd:d9:dd:c25:c25:94de:e4e3
1152c19:dd:d9:dd:c25:c25:94de:e4e4/1272c19:dd:d9:dd:c25:c25:94de:e4e5
1162c19:dd:d9:dd:c25:c25:94de:e4e6/1272c19:dd:d9:dd:c25:c25:94de:e4e7
1172c19:dd:d9:dd:c25:c25:94de:e4e8/1272c19:dd:d9:dd:c25:c25:94de:e4e9
1182c19:dd:d9:dd:c25:c25:94de:e4ea/1272c19:dd:d9:dd:c25:c25:94de:e4eb
1192c19:dd:d9:dd:c25:c25:94de:e4ec/1272c19:dd:d9:dd:c25:c25:94de:e4ed
1202c19:dd:d9:dd:c25:c25:94de:e4ee/1272c19:dd:d9:dd:c25:c25:94de:e4ef
1212c19:dd:d9:dd:c25:c25:94de:e4f0/1272c19:dd:d9:dd:c25:c25:94de:e4f1
1222c19:dd:d9:dd:c25:c25:94de:e4f2/1272c19:dd:d9:dd:c25:c25:94de:e4f3
1232c19:dd:d9:dd:c25:c25:94de:e4f4/1272c19:dd:d9:dd:c25:c25:94de:e4f5
1242c19:dd:d9:dd:c25:c25:94de:e4f6/1272c19:dd:d9:dd:c25:c25:94de:e4f7
1252c19:dd:d9:dd:c25:c25:94de:e4f8/1272c19:dd:d9:dd:c25:c25:94de:e4f9
1262c19:dd:d9:dd:c25:c25:94de:e4fa/1272c19:dd:d9:dd:c25:c25:94de:e4fb
1272c19:dd:d9:dd:c25:c25:94de:e4fc/1272c19:dd:d9:dd:c25:c25:94de:e4fd
1282c19:dd:d9:dd:c25:c25:94de:e4fe/1272c19:dd:d9:dd:c25:c25:94de:e4ff
1292c19:dd:d9:dd:c25:c25:94de:e500/1272c19:dd:d9:dd:c25:c25:94de:e501
1302c19:dd:d9:dd:c25:c25:94de:e502/1272c19:dd:d9:dd:c25:c25:94de:e503
1312c19:dd:d9:dd:c25:c25:94de:e504/1272c19:dd:d9:dd:c25:c25:94de:e505
1322c19:dd:d9:dd:c25:c25:94de:e506/1272c19:dd:d9:dd:c25:c25:94de:e507
1332c19:dd:d9:dd:c25:c25:94de:e508/1272c19:dd:d9:dd:c25:c25:94de:e509
1342c19:dd:d9:dd:c25:c25:94de:e50a/1272c19:dd:d9:dd:c25:c25:94de:e50b
1352c19:dd:d9:dd:c25:c25:94de:e50c/1272c19:dd:d9:dd:c25:c25:94de:e50d
1362c19:dd:d9:dd:c25:c25:94de:e50e/1272c19:dd:d9:dd:c25:c25:94de:e50f
1372c19:dd:d9:dd:c25:c25:94de:e510/1272c19:dd:d9:dd:c25:c25:94de:e511
1382c19:dd:d9:dd:c25:c25:94de:e512/1272c19:dd:d9:dd:c25:c25:94de:e513
1392c19:dd:d9:dd:c25:c25:94de:e514/1272c19:dd:d9:dd:c25:c25:94de:e515
1402c19:dd:d9:dd:c25:c25:94de:e516/1272c19:dd:d9:dd:c25:c25:94de:e517
1412c19:dd:d9:dd:c25:c25:94de:e518/1272c19:dd:d9:dd:c25:c25:94de:e519
1422c19:dd:d9:dd:c25:c25:94de:e51a/1272c19:dd:d9:dd:c25:c25:94de:e51b
1432c19:dd:d9:dd:c25:c25:94de:e51c/1272c19:dd:d9:dd:c25:c25:94de:e51d
1442c19:dd:d9:dd:c25:c25:94de:e51e/1272c19:dd:d9:dd:c25:c25:94de:e51f
1452c19:dd:d9:dd:c25:c25:94de:e520/1272c19:dd:d9:dd:c25:c25:94de:e521
1462c19:dd:d9:dd:c25:c25:94de:e522/1272c19:dd:d9:dd:c25:c25:94de:e523
1472c19:dd:d9:dd:c25:c25:94de:e524/1272c19:dd:d9:dd:c25:c25:94de:e525
1482c19:dd:d9:dd:c25:c25:94de:e526/1272c19:dd:d9:dd:c25:c25:94de:e527
1492c19:dd:d9:dd:c25:c25:94de:e528/1272c19:dd:d9:dd:c25:c25:94de:e529
1502c19:dd:d9:dd:c25:c25:94de:e52a/1272c19:dd:d9:dd:c25:c25:94de:e52b
1512c19:dd:d9:dd:c25:c25:94de:e52c/1272c19:dd:d9:dd:c25:c25:94de:e52d
1522c19:dd:d9:dd:c25:c25:94de:e52e/1272c19:dd:d9:dd:c25:c25:94de:e52f
1532c19:dd:d9:dd:c25:c25:94de:e530/1272c19:dd:d9:dd:c25:c25:94de:e531
1542c19:dd:d9:dd:c25:c25:94de:e532/1272c19:dd:d9:dd:c25:c25:94de:e533
1552c19:dd:d9:dd:c25:c25:94de:e534/1272c19:dd:d9:dd:c25:c25:94de:e535
1562c19:dd:d9:dd:c25:c25:94de:e536/1272c19:dd:d9:dd:c25:c25:94de:e537
1572c19:dd:d9:dd:c25:c25:94de:e538/1272c19:dd:d9:dd:c25:c25:94de:e539
1582c19:dd:d9:dd:c25:c25:94de:e53a/1272c19:dd:d9:dd:c25:c25:94de:e53b
1592c19:dd:d9:dd:c25:c25:94de:e53c/1272c19:dd:d9:dd:c25:c25:94de:e53d
1602c19:dd:d9:dd:c25:c25:94de:e53e/1272c19:dd:d9:dd:c25:c25:94de:e53f
1612c19:dd:d9:dd:c25:c25:94de:e540/1272c19:dd:d9:dd:c25:c25:94de:e541
1622c19:dd:d9:dd:c25:c25:94de:e542/1272c19:dd:d9:dd:c25:c25:94de:e543
1632c19:dd:d9:dd:c25:c25:94de:e544/1272c19:dd:d9:dd:c25:c25:94de:e545
1642c19:dd:d9:dd:c25:c25:94de:e546/1272c19:dd:d9:dd:c25:c25:94de:e547
1652c19:dd:d9:dd:c25:c25:94de:e548/1272c19:dd:d9:dd:c25:c25:94de:e549
1662c19:dd:d9:dd:c25:c25:94de:e54a/1272c19:dd:d9:dd:c25:c25:94de:e54b
1672c19:dd:d9:dd:c25:c25:94de:e54c/1272c19:dd:d9:dd:c25:c25:94de:e54d
1682c19:dd:d9:dd:c25:c25:94de:e54e/1272c19:dd:d9:dd:c25:c25:94de:e54f
1692c19:dd:d9:dd:c25:c25:94de:e550/1272c19:dd:d9:dd:c25:c25:94de:e551
1702c19:dd:d9:dd:c25:c25:94de:e552/1272c19:dd:d9:dd:c25:c25:94de:e553
1712c19:dd:d9:dd:c25:c25:94de:e554/1272c19:dd:d9:dd:c25:c25:94de:e555
1722c19:dd:d9:dd:c25:c25:94de:e556/1272c19:dd:d9:dd:c25:c25:94de:e557
1732c19:dd:d9:dd:c25:c25:94de:e558/1272c19:dd:d9:dd:c25:c25:94de:e559
1742c19:dd:d9:dd:c25:c25:94de:e55a/1272c19:dd:d9:dd:c25:c25:94de:e55b
1752c19:dd:d9:dd:c25:c25:94de:e55c/1272c19:dd:d9:dd:c25:c25:94de:e55d
1762c19:dd:d9:dd:c25:c25:94de:e55e/1272c19:dd:d9:dd:c25:c25:94de:e55f
1772c19:dd:d9:dd:c25:c25:94de:e560/1272c19:dd:d9:dd:c25:c25:94de:e561
1782c19:dd:d9:dd:c25:c25:94de:e562/1272c19:dd:d9:dd:c25:c25:94de:e563
1792c19:dd:d9:dd:c25:c25:94de:e564/1272c19:dd:d9:dd:c25:c25:94de:e565
1802c19:dd:d9:dd:c25:c25:94de:e566/1272c19:dd:d9:dd:c25:c25:94de:e567
1812c19:dd:d9:dd:c25:c25:94de:e568/1272c19:dd:d9:dd:c25:c25:94de:e569
1822c19:dd:d9:dd:c25:c25:94de:e56a/1272c19:dd:d9:dd:c25:c25:94de:e56b
1832c19:dd:d9:dd:c25:c25:94de:e56c/1272c19:dd:d9:dd:c25:c25:94de:e56d
1842c19:dd:d9:dd:c25:c25:94de:e56e/1272c19:dd:d9:dd:c25:c25:94de:e56f
1852c19:dd:d9:dd:c25:c25:94de:e570/1272c19:dd:d9:dd:c25:c25:94de:e571
1862c19:dd:d9:dd:c25:c25:94de:e572/1272c19:dd:d9:dd:c25:c25:94de:e573
1872c19:dd:d9:dd:c25:c25:94de:e574/1272c19:dd:d9:dd:c25:c25:94de:e575
1882c19:dd:d9:dd:c25:c25:94de:e576/1272c19:dd:d9:dd:c25:c25:94de:e577
1892c19:dd:d9:dd:c25:c25:94de:e578/1272c19:dd:d9:dd:c25:c25:94de:e579
1902c19:dd:d9:dd:c25:c25:94de:e57a/1272c19:dd:d9:dd:c25:c25:94de:e57b
1912c19:dd:d9:dd:c25:c25:94de:e57c/1272c19:dd:d9:dd:c25:c25:94de:e57d
1922c19:dd:d9:dd:c25:c25:94de:e57e/1272c19:dd:d9:dd:c25:c25:94de:e57f
1932c19:dd:d9:dd:c25:c25:94de:e580/1272c19:dd:d9:dd:c25:c25:94de:e581
1942c19:dd:d9:dd:c25:c25:94de:e582/1272c19:dd:d9:dd:c25:c25:94de:e583
1952c19:dd:d9:dd:c25:c25:94de:e584/1272c19:dd:d9:dd:c25:c25:94de:e585
1962c19:dd:d9:dd:c25:c25:94de:e586/1272c19:dd:d9:dd:c25:c25:94de:e587
1972c19:dd:d9:dd:c25:c25:94de:e588/1272c19:dd:d9:dd:c25:c25:94de:e589
1982c19:dd:d9:dd:c25:c25:94de:e58a/1272c19:dd:d9:dd:c25:c25:94de:e58b
1992c19:dd:d9:dd:c25:c25:94de:e58c/1272c19:dd:d9:dd:c25:c25:94de:e58d
2002c19:dd:d9:dd:c25:c25:94de:e58e/1272c19:dd:d9:dd:c25:c25:94de:e58f
2012c19:dd:d9:dd:c25:c25:94de:e590/1272c19:dd:d9:dd:c25:c25:94de:e591
2022c19:dd:d9:dd:c25:c25:94de:e592/1272c19:dd:d9:dd:c25:c25:94de:e593
2032c19:dd:d9:dd:c25:c25:94de:e594/1272c19:dd:d9:dd:c25:c25:94de:e595
2042c19:dd:d9:dd:c25:c25:94de:e596/1272c19:dd:d9:dd:c25:c25:94de:e597
2052c19:dd:d9:dd:c25:c25:94de:e598/1272c19:dd:d9:dd:c25:c25:94de:e599
2062c19:dd:d9:dd:c25:c25:94de:e59a/1272c19:dd:d9:dd:c25:c25:94de:e59b
2072c19:dd:d9:dd:c25:c25:94de:e59c/1272c19:dd:d9:dd:c25:c25:94de:e59d
2082c19:dd:d9:dd:c25:c25:94de:e59e/1272c19:dd:d9:dd:c25:c25:94de:e59f
2092c19:dd:d9:dd:c25:c25:94de:e5a0/1272c19:dd:d9:dd:c25:c25:94de:e5a1
2102c19:dd:d9:dd:c25:c25:94de:e5a2/1272c19:dd:d9:dd:c25:c25:94de:e5a3
2112c19:dd:d9:dd:c25:c25:94de:e5a4/1272c19:dd:d9:dd:c25:c25:94de:e5a5
2122c19:dd:d9:dd:c25:c25:94de:e5a6/1272c19:dd:d9:dd:c25:c25:94de:e5a7
2132c19:dd:d9:dd:c25:c25:94de:e5a8/1272c19:dd:d9:dd:c25:c25:94de:e5a9
2142c19:dd:d9:dd:c25:c25:94de:e5aa/1272c19:dd:d9:dd:c25:c25:94de:e5ab
2152c19:dd:d9:dd:c25:c25:94de:e5ac/1272c19:dd:d9:dd:c25:c25:94de:e5ad
2162c19:dd:d9:dd:c25:c25:94de:e5ae/1272c19:dd:d9:dd:c25:c25:94de:e5af
2172c19:dd:d9:dd:c25:c25:94de:e5b0/1272c19:dd:d9:dd:c25:c25:94de:e5b1
2182c19:dd:d9:dd:c25:c25:94de:e5b2/1272c19:dd:d9:dd:c25:c25:94de:e5b3
2192c19:dd:d9:dd:c25:c25:94de:e5b4/1272c19:dd:d9:dd:c25:c25:94de:e5b5
2202c19:dd:d9:dd:c25:c25:94de:e5b6/1272c19:dd:d9:dd:c25:c25:94de:e5b7
2212c19:dd:d9:dd:c25:c25:94de:e5b8/1272c19:dd:d9:dd:c25:c25:94de:e5b9
2222c19:dd:d9:dd:c25:c25:94de:e5ba/1272c19:dd:d9:dd:c25:c25:94de:e5bb
2232c19:dd:d9:dd:c25:c25:94de:e5bc/1272c19:dd:d9:dd:c25:c25:94de:e5bd
2242c19:dd:d9:dd:c25:c25:94de:e5be/1272c19:dd:d9:dd:c25:c25:94de:e5bf
2252c19:dd:d9:dd:c25:c25:94de:e5c0/1272c19:dd:d9:dd:c25:c25:94de:e5c1
2262c19:dd:d9:dd:c25:c25:94de:e5c2/1272c19:dd:d9:dd:c25:c25:94de:e5c3
2272c19:dd:d9:dd:c25:c25:94de:e5c4/1272c19:dd:d9:dd:c25:c25:94de:e5c5
2282c19:dd:d9:dd:c25:c25:94de:e5c6/1272c19:dd:d9:dd:c25:c25:94de:e5c7
2292c19:dd:d9:dd:c25:c25:94de:e5c8/1272c19:dd:d9:dd:c25:c25:94de:e5c9
2302c19:dd:d9:dd:c25:c25:94de:e5ca/1272c19:dd:d9:dd:c25:c25:94de:e5cb
2312c19:dd:d9:dd:c25:c25:94de:e5cc/1272c19:dd:d9:dd:c25:c25:94de:e5cd
2322c19:dd:d9:dd:c25:c25:94de:e5ce/1272c19:dd:d9:dd:c25:c25:94de:e5cf
2332c19:dd:d9:dd:c25:c25:94de:e5d0/1272c19:dd:d9:dd:c25:c25:94de:e5d1
2342c19:dd:d9:dd:c25:c25:94de:e5d2/1272c19:dd:d9:dd:c25:c25:94de:e5d3
2352c19:dd:d9:dd:c25:c25:94de:e5d4/1272c19:dd:d9:dd:c25:c25:94de:e5d5
2362c19:dd:d9:dd:c25:c25:94de:e5d6/1272c19:dd:d9:dd:c25:c25:94de:e5d7
2372c19:dd:d9:dd:c25:c25:94de:e5d8/1272c19:dd:d9:dd:c25:c25:94de:e5d9
2382c19:dd:d9:dd:c25:c25:94de:e5da/1272c19:dd:d9:dd:c25:c25:94de:e5db
2392c19:dd:d9:dd:c25:c25:94de:e5dc/1272c19:dd:d9:dd:c25:c25:94de:e5dd
2402c19:dd:d9:dd:c25:c25:94de:e5de/1272c19:dd:d9:dd:c25:c25:94de:e5df
2412c19:dd:d9:dd:c25:c25:94de:e5e0/1272c19:dd:d9:dd:c25:c25:94de:e5e1
2422c19:dd:d9:dd:c25:c25:94de:e5e2/1272c19:dd:d9:dd:c25:c25:94de:e5e3
2432c19:dd:d9:dd:c25:c25:94de:e5e4/1272c19:dd:d9:dd:c25:c25:94de:e5e5
2442c19:dd:d9:dd:c25:c25:94de:e5e6/1272c19:dd:d9:dd:c25:c25:94de:e5e7
2452c19:dd:d9:dd:c25:c25:94de:e5e8/1272c19:dd:d9:dd:c25:c25:94de:e5e9
2462c19:dd:d9:dd:c25:c25:94de:e5ea/1272c19:dd:d9:dd:c25:c25:94de:e5eb
2472c19:dd:d9:dd:c25:c25:94de:e5ec/1272c19:dd:d9:dd:c25:c25:94de:e5ed
2482c19:dd:d9:dd:c25:c25:94de:e5ee/1272c19:dd:d9:dd:c25:c25:94de:e5ef
2492c19:dd:d9:dd:c25:c25:94de:e5f0/1272c19:dd:d9:dd:c25:c25:94de:e5f1
2502c19:dd:d9:dd:c25:c25:94de:e5f2/1272c19:dd:d9:dd:c25:c25:94de:e5f3
2512c19:dd:d9:dd:c25:c25:94de:e5f4/1272c19:dd:d9:dd:c25:c25:94de:e5f5
2522c19:dd:d9:dd:c25:c25:94de:e5f6/1272c19:dd:d9:dd:c25:c25:94de:e5f7
2532c19:dd:d9:dd:c25:c25:94de:e5f8/1272c19:dd:d9:dd:c25:c25:94de:e5f9
2542c19:dd:d9:dd:c25:c25:94de:e5fa/1272c19:dd:d9:dd:c25:c25:94de:e5fb
2552c19:dd:d9:dd:c25:c25:94de:e5fc/1272c19:dd:d9:dd:c25:c25:94de:e5fd
2562c19:dd:d9:dd:c25:c25:94de:e5fe/1272c19:dd:d9:dd:c25:c25:94de:e5ff

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.