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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:c25:c25d:dd:dd:dd:b400/119
First address
2c19:dd:c25:c25d:dd:dd:dd:b400
Last address
2c19:dd:c25:c25d:dd:dd:dd:b5ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:b400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
4.b.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
5.b.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.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:c25:c25d:dd:dd:dd:b400/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:b400/1272c19:dd:c25:c25d:dd:dd:dd:b401
22c19:dd:c25:c25d:dd:dd:dd:b402/1272c19:dd:c25:c25d:dd:dd:dd:b403
32c19:dd:c25:c25d:dd:dd:dd:b404/1272c19:dd:c25:c25d:dd:dd:dd:b405
42c19:dd:c25:c25d:dd:dd:dd:b406/1272c19:dd:c25:c25d:dd:dd:dd:b407
52c19:dd:c25:c25d:dd:dd:dd:b408/1272c19:dd:c25:c25d:dd:dd:dd:b409
62c19:dd:c25:c25d:dd:dd:dd:b40a/1272c19:dd:c25:c25d:dd:dd:dd:b40b
72c19:dd:c25:c25d:dd:dd:dd:b40c/1272c19:dd:c25:c25d:dd:dd:dd:b40d
82c19:dd:c25:c25d:dd:dd:dd:b40e/1272c19:dd:c25:c25d:dd:dd:dd:b40f
92c19:dd:c25:c25d:dd:dd:dd:b410/1272c19:dd:c25:c25d:dd:dd:dd:b411
102c19:dd:c25:c25d:dd:dd:dd:b412/1272c19:dd:c25:c25d:dd:dd:dd:b413
112c19:dd:c25:c25d:dd:dd:dd:b414/1272c19:dd:c25:c25d:dd:dd:dd:b415
122c19:dd:c25:c25d:dd:dd:dd:b416/1272c19:dd:c25:c25d:dd:dd:dd:b417
132c19:dd:c25:c25d:dd:dd:dd:b418/1272c19:dd:c25:c25d:dd:dd:dd:b419
142c19:dd:c25:c25d:dd:dd:dd:b41a/1272c19:dd:c25:c25d:dd:dd:dd:b41b
152c19:dd:c25:c25d:dd:dd:dd:b41c/1272c19:dd:c25:c25d:dd:dd:dd:b41d
162c19:dd:c25:c25d:dd:dd:dd:b41e/1272c19:dd:c25:c25d:dd:dd:dd:b41f
172c19:dd:c25:c25d:dd:dd:dd:b420/1272c19:dd:c25:c25d:dd:dd:dd:b421
182c19:dd:c25:c25d:dd:dd:dd:b422/1272c19:dd:c25:c25d:dd:dd:dd:b423
192c19:dd:c25:c25d:dd:dd:dd:b424/1272c19:dd:c25:c25d:dd:dd:dd:b425
202c19:dd:c25:c25d:dd:dd:dd:b426/1272c19:dd:c25:c25d:dd:dd:dd:b427
212c19:dd:c25:c25d:dd:dd:dd:b428/1272c19:dd:c25:c25d:dd:dd:dd:b429
222c19:dd:c25:c25d:dd:dd:dd:b42a/1272c19:dd:c25:c25d:dd:dd:dd:b42b
232c19:dd:c25:c25d:dd:dd:dd:b42c/1272c19:dd:c25:c25d:dd:dd:dd:b42d
242c19:dd:c25:c25d:dd:dd:dd:b42e/1272c19:dd:c25:c25d:dd:dd:dd:b42f
252c19:dd:c25:c25d:dd:dd:dd:b430/1272c19:dd:c25:c25d:dd:dd:dd:b431
262c19:dd:c25:c25d:dd:dd:dd:b432/1272c19:dd:c25:c25d:dd:dd:dd:b433
272c19:dd:c25:c25d:dd:dd:dd:b434/1272c19:dd:c25:c25d:dd:dd:dd:b435
282c19:dd:c25:c25d:dd:dd:dd:b436/1272c19:dd:c25:c25d:dd:dd:dd:b437
292c19:dd:c25:c25d:dd:dd:dd:b438/1272c19:dd:c25:c25d:dd:dd:dd:b439
302c19:dd:c25:c25d:dd:dd:dd:b43a/1272c19:dd:c25:c25d:dd:dd:dd:b43b
312c19:dd:c25:c25d:dd:dd:dd:b43c/1272c19:dd:c25:c25d:dd:dd:dd:b43d
322c19:dd:c25:c25d:dd:dd:dd:b43e/1272c19:dd:c25:c25d:dd:dd:dd:b43f
332c19:dd:c25:c25d:dd:dd:dd:b440/1272c19:dd:c25:c25d:dd:dd:dd:b441
342c19:dd:c25:c25d:dd:dd:dd:b442/1272c19:dd:c25:c25d:dd:dd:dd:b443
352c19:dd:c25:c25d:dd:dd:dd:b444/1272c19:dd:c25:c25d:dd:dd:dd:b445
362c19:dd:c25:c25d:dd:dd:dd:b446/1272c19:dd:c25:c25d:dd:dd:dd:b447
372c19:dd:c25:c25d:dd:dd:dd:b448/1272c19:dd:c25:c25d:dd:dd:dd:b449
382c19:dd:c25:c25d:dd:dd:dd:b44a/1272c19:dd:c25:c25d:dd:dd:dd:b44b
392c19:dd:c25:c25d:dd:dd:dd:b44c/1272c19:dd:c25:c25d:dd:dd:dd:b44d
402c19:dd:c25:c25d:dd:dd:dd:b44e/1272c19:dd:c25:c25d:dd:dd:dd:b44f
412c19:dd:c25:c25d:dd:dd:dd:b450/1272c19:dd:c25:c25d:dd:dd:dd:b451
422c19:dd:c25:c25d:dd:dd:dd:b452/1272c19:dd:c25:c25d:dd:dd:dd:b453
432c19:dd:c25:c25d:dd:dd:dd:b454/1272c19:dd:c25:c25d:dd:dd:dd:b455
442c19:dd:c25:c25d:dd:dd:dd:b456/1272c19:dd:c25:c25d:dd:dd:dd:b457
452c19:dd:c25:c25d:dd:dd:dd:b458/1272c19:dd:c25:c25d:dd:dd:dd:b459
462c19:dd:c25:c25d:dd:dd:dd:b45a/1272c19:dd:c25:c25d:dd:dd:dd:b45b
472c19:dd:c25:c25d:dd:dd:dd:b45c/1272c19:dd:c25:c25d:dd:dd:dd:b45d
482c19:dd:c25:c25d:dd:dd:dd:b45e/1272c19:dd:c25:c25d:dd:dd:dd:b45f
492c19:dd:c25:c25d:dd:dd:dd:b460/1272c19:dd:c25:c25d:dd:dd:dd:b461
502c19:dd:c25:c25d:dd:dd:dd:b462/1272c19:dd:c25:c25d:dd:dd:dd:b463
512c19:dd:c25:c25d:dd:dd:dd:b464/1272c19:dd:c25:c25d:dd:dd:dd:b465
522c19:dd:c25:c25d:dd:dd:dd:b466/1272c19:dd:c25:c25d:dd:dd:dd:b467
532c19:dd:c25:c25d:dd:dd:dd:b468/1272c19:dd:c25:c25d:dd:dd:dd:b469
542c19:dd:c25:c25d:dd:dd:dd:b46a/1272c19:dd:c25:c25d:dd:dd:dd:b46b
552c19:dd:c25:c25d:dd:dd:dd:b46c/1272c19:dd:c25:c25d:dd:dd:dd:b46d
562c19:dd:c25:c25d:dd:dd:dd:b46e/1272c19:dd:c25:c25d:dd:dd:dd:b46f
572c19:dd:c25:c25d:dd:dd:dd:b470/1272c19:dd:c25:c25d:dd:dd:dd:b471
582c19:dd:c25:c25d:dd:dd:dd:b472/1272c19:dd:c25:c25d:dd:dd:dd:b473
592c19:dd:c25:c25d:dd:dd:dd:b474/1272c19:dd:c25:c25d:dd:dd:dd:b475
602c19:dd:c25:c25d:dd:dd:dd:b476/1272c19:dd:c25:c25d:dd:dd:dd:b477
612c19:dd:c25:c25d:dd:dd:dd:b478/1272c19:dd:c25:c25d:dd:dd:dd:b479
622c19:dd:c25:c25d:dd:dd:dd:b47a/1272c19:dd:c25:c25d:dd:dd:dd:b47b
632c19:dd:c25:c25d:dd:dd:dd:b47c/1272c19:dd:c25:c25d:dd:dd:dd:b47d
642c19:dd:c25:c25d:dd:dd:dd:b47e/1272c19:dd:c25:c25d:dd:dd:dd:b47f
652c19:dd:c25:c25d:dd:dd:dd:b480/1272c19:dd:c25:c25d:dd:dd:dd:b481
662c19:dd:c25:c25d:dd:dd:dd:b482/1272c19:dd:c25:c25d:dd:dd:dd:b483
672c19:dd:c25:c25d:dd:dd:dd:b484/1272c19:dd:c25:c25d:dd:dd:dd:b485
682c19:dd:c25:c25d:dd:dd:dd:b486/1272c19:dd:c25:c25d:dd:dd:dd:b487
692c19:dd:c25:c25d:dd:dd:dd:b488/1272c19:dd:c25:c25d:dd:dd:dd:b489
702c19:dd:c25:c25d:dd:dd:dd:b48a/1272c19:dd:c25:c25d:dd:dd:dd:b48b
712c19:dd:c25:c25d:dd:dd:dd:b48c/1272c19:dd:c25:c25d:dd:dd:dd:b48d
722c19:dd:c25:c25d:dd:dd:dd:b48e/1272c19:dd:c25:c25d:dd:dd:dd:b48f
732c19:dd:c25:c25d:dd:dd:dd:b490/1272c19:dd:c25:c25d:dd:dd:dd:b491
742c19:dd:c25:c25d:dd:dd:dd:b492/1272c19:dd:c25:c25d:dd:dd:dd:b493
752c19:dd:c25:c25d:dd:dd:dd:b494/1272c19:dd:c25:c25d:dd:dd:dd:b495
762c19:dd:c25:c25d:dd:dd:dd:b496/1272c19:dd:c25:c25d:dd:dd:dd:b497
772c19:dd:c25:c25d:dd:dd:dd:b498/1272c19:dd:c25:c25d:dd:dd:dd:b499
782c19:dd:c25:c25d:dd:dd:dd:b49a/1272c19:dd:c25:c25d:dd:dd:dd:b49b
792c19:dd:c25:c25d:dd:dd:dd:b49c/1272c19:dd:c25:c25d:dd:dd:dd:b49d
802c19:dd:c25:c25d:dd:dd:dd:b49e/1272c19:dd:c25:c25d:dd:dd:dd:b49f
812c19:dd:c25:c25d:dd:dd:dd:b4a0/1272c19:dd:c25:c25d:dd:dd:dd:b4a1
822c19:dd:c25:c25d:dd:dd:dd:b4a2/1272c19:dd:c25:c25d:dd:dd:dd:b4a3
832c19:dd:c25:c25d:dd:dd:dd:b4a4/1272c19:dd:c25:c25d:dd:dd:dd:b4a5
842c19:dd:c25:c25d:dd:dd:dd:b4a6/1272c19:dd:c25:c25d:dd:dd:dd:b4a7
852c19:dd:c25:c25d:dd:dd:dd:b4a8/1272c19:dd:c25:c25d:dd:dd:dd:b4a9
862c19:dd:c25:c25d:dd:dd:dd:b4aa/1272c19:dd:c25:c25d:dd:dd:dd:b4ab
872c19:dd:c25:c25d:dd:dd:dd:b4ac/1272c19:dd:c25:c25d:dd:dd:dd:b4ad
882c19:dd:c25:c25d:dd:dd:dd:b4ae/1272c19:dd:c25:c25d:dd:dd:dd:b4af
892c19:dd:c25:c25d:dd:dd:dd:b4b0/1272c19:dd:c25:c25d:dd:dd:dd:b4b1
902c19:dd:c25:c25d:dd:dd:dd:b4b2/1272c19:dd:c25:c25d:dd:dd:dd:b4b3
912c19:dd:c25:c25d:dd:dd:dd:b4b4/1272c19:dd:c25:c25d:dd:dd:dd:b4b5
922c19:dd:c25:c25d:dd:dd:dd:b4b6/1272c19:dd:c25:c25d:dd:dd:dd:b4b7
932c19:dd:c25:c25d:dd:dd:dd:b4b8/1272c19:dd:c25:c25d:dd:dd:dd:b4b9
942c19:dd:c25:c25d:dd:dd:dd:b4ba/1272c19:dd:c25:c25d:dd:dd:dd:b4bb
952c19:dd:c25:c25d:dd:dd:dd:b4bc/1272c19:dd:c25:c25d:dd:dd:dd:b4bd
962c19:dd:c25:c25d:dd:dd:dd:b4be/1272c19:dd:c25:c25d:dd:dd:dd:b4bf
972c19:dd:c25:c25d:dd:dd:dd:b4c0/1272c19:dd:c25:c25d:dd:dd:dd:b4c1
982c19:dd:c25:c25d:dd:dd:dd:b4c2/1272c19:dd:c25:c25d:dd:dd:dd:b4c3
992c19:dd:c25:c25d:dd:dd:dd:b4c4/1272c19:dd:c25:c25d:dd:dd:dd:b4c5
1002c19:dd:c25:c25d:dd:dd:dd:b4c6/1272c19:dd:c25:c25d:dd:dd:dd:b4c7
1012c19:dd:c25:c25d:dd:dd:dd:b4c8/1272c19:dd:c25:c25d:dd:dd:dd:b4c9
1022c19:dd:c25:c25d:dd:dd:dd:b4ca/1272c19:dd:c25:c25d:dd:dd:dd:b4cb
1032c19:dd:c25:c25d:dd:dd:dd:b4cc/1272c19:dd:c25:c25d:dd:dd:dd:b4cd
1042c19:dd:c25:c25d:dd:dd:dd:b4ce/1272c19:dd:c25:c25d:dd:dd:dd:b4cf
1052c19:dd:c25:c25d:dd:dd:dd:b4d0/1272c19:dd:c25:c25d:dd:dd:dd:b4d1
1062c19:dd:c25:c25d:dd:dd:dd:b4d2/1272c19:dd:c25:c25d:dd:dd:dd:b4d3
1072c19:dd:c25:c25d:dd:dd:dd:b4d4/1272c19:dd:c25:c25d:dd:dd:dd:b4d5
1082c19:dd:c25:c25d:dd:dd:dd:b4d6/1272c19:dd:c25:c25d:dd:dd:dd:b4d7
1092c19:dd:c25:c25d:dd:dd:dd:b4d8/1272c19:dd:c25:c25d:dd:dd:dd:b4d9
1102c19:dd:c25:c25d:dd:dd:dd:b4da/1272c19:dd:c25:c25d:dd:dd:dd:b4db
1112c19:dd:c25:c25d:dd:dd:dd:b4dc/1272c19:dd:c25:c25d:dd:dd:dd:b4dd
1122c19:dd:c25:c25d:dd:dd:dd:b4de/1272c19:dd:c25:c25d:dd:dd:dd:b4df
1132c19:dd:c25:c25d:dd:dd:dd:b4e0/1272c19:dd:c25:c25d:dd:dd:dd:b4e1
1142c19:dd:c25:c25d:dd:dd:dd:b4e2/1272c19:dd:c25:c25d:dd:dd:dd:b4e3
1152c19:dd:c25:c25d:dd:dd:dd:b4e4/1272c19:dd:c25:c25d:dd:dd:dd:b4e5
1162c19:dd:c25:c25d:dd:dd:dd:b4e6/1272c19:dd:c25:c25d:dd:dd:dd:b4e7
1172c19:dd:c25:c25d:dd:dd:dd:b4e8/1272c19:dd:c25:c25d:dd:dd:dd:b4e9
1182c19:dd:c25:c25d:dd:dd:dd:b4ea/1272c19:dd:c25:c25d:dd:dd:dd:b4eb
1192c19:dd:c25:c25d:dd:dd:dd:b4ec/1272c19:dd:c25:c25d:dd:dd:dd:b4ed
1202c19:dd:c25:c25d:dd:dd:dd:b4ee/1272c19:dd:c25:c25d:dd:dd:dd:b4ef
1212c19:dd:c25:c25d:dd:dd:dd:b4f0/1272c19:dd:c25:c25d:dd:dd:dd:b4f1
1222c19:dd:c25:c25d:dd:dd:dd:b4f2/1272c19:dd:c25:c25d:dd:dd:dd:b4f3
1232c19:dd:c25:c25d:dd:dd:dd:b4f4/1272c19:dd:c25:c25d:dd:dd:dd:b4f5
1242c19:dd:c25:c25d:dd:dd:dd:b4f6/1272c19:dd:c25:c25d:dd:dd:dd:b4f7
1252c19:dd:c25:c25d:dd:dd:dd:b4f8/1272c19:dd:c25:c25d:dd:dd:dd:b4f9
1262c19:dd:c25:c25d:dd:dd:dd:b4fa/1272c19:dd:c25:c25d:dd:dd:dd:b4fb
1272c19:dd:c25:c25d:dd:dd:dd:b4fc/1272c19:dd:c25:c25d:dd:dd:dd:b4fd
1282c19:dd:c25:c25d:dd:dd:dd:b4fe/1272c19:dd:c25:c25d:dd:dd:dd:b4ff
1292c19:dd:c25:c25d:dd:dd:dd:b500/1272c19:dd:c25:c25d:dd:dd:dd:b501
1302c19:dd:c25:c25d:dd:dd:dd:b502/1272c19:dd:c25:c25d:dd:dd:dd:b503
1312c19:dd:c25:c25d:dd:dd:dd:b504/1272c19:dd:c25:c25d:dd:dd:dd:b505
1322c19:dd:c25:c25d:dd:dd:dd:b506/1272c19:dd:c25:c25d:dd:dd:dd:b507
1332c19:dd:c25:c25d:dd:dd:dd:b508/1272c19:dd:c25:c25d:dd:dd:dd:b509
1342c19:dd:c25:c25d:dd:dd:dd:b50a/1272c19:dd:c25:c25d:dd:dd:dd:b50b
1352c19:dd:c25:c25d:dd:dd:dd:b50c/1272c19:dd:c25:c25d:dd:dd:dd:b50d
1362c19:dd:c25:c25d:dd:dd:dd:b50e/1272c19:dd:c25:c25d:dd:dd:dd:b50f
1372c19:dd:c25:c25d:dd:dd:dd:b510/1272c19:dd:c25:c25d:dd:dd:dd:b511
1382c19:dd:c25:c25d:dd:dd:dd:b512/1272c19:dd:c25:c25d:dd:dd:dd:b513
1392c19:dd:c25:c25d:dd:dd:dd:b514/1272c19:dd:c25:c25d:dd:dd:dd:b515
1402c19:dd:c25:c25d:dd:dd:dd:b516/1272c19:dd:c25:c25d:dd:dd:dd:b517
1412c19:dd:c25:c25d:dd:dd:dd:b518/1272c19:dd:c25:c25d:dd:dd:dd:b519
1422c19:dd:c25:c25d:dd:dd:dd:b51a/1272c19:dd:c25:c25d:dd:dd:dd:b51b
1432c19:dd:c25:c25d:dd:dd:dd:b51c/1272c19:dd:c25:c25d:dd:dd:dd:b51d
1442c19:dd:c25:c25d:dd:dd:dd:b51e/1272c19:dd:c25:c25d:dd:dd:dd:b51f
1452c19:dd:c25:c25d:dd:dd:dd:b520/1272c19:dd:c25:c25d:dd:dd:dd:b521
1462c19:dd:c25:c25d:dd:dd:dd:b522/1272c19:dd:c25:c25d:dd:dd:dd:b523
1472c19:dd:c25:c25d:dd:dd:dd:b524/1272c19:dd:c25:c25d:dd:dd:dd:b525
1482c19:dd:c25:c25d:dd:dd:dd:b526/1272c19:dd:c25:c25d:dd:dd:dd:b527
1492c19:dd:c25:c25d:dd:dd:dd:b528/1272c19:dd:c25:c25d:dd:dd:dd:b529
1502c19:dd:c25:c25d:dd:dd:dd:b52a/1272c19:dd:c25:c25d:dd:dd:dd:b52b
1512c19:dd:c25:c25d:dd:dd:dd:b52c/1272c19:dd:c25:c25d:dd:dd:dd:b52d
1522c19:dd:c25:c25d:dd:dd:dd:b52e/1272c19:dd:c25:c25d:dd:dd:dd:b52f
1532c19:dd:c25:c25d:dd:dd:dd:b530/1272c19:dd:c25:c25d:dd:dd:dd:b531
1542c19:dd:c25:c25d:dd:dd:dd:b532/1272c19:dd:c25:c25d:dd:dd:dd:b533
1552c19:dd:c25:c25d:dd:dd:dd:b534/1272c19:dd:c25:c25d:dd:dd:dd:b535
1562c19:dd:c25:c25d:dd:dd:dd:b536/1272c19:dd:c25:c25d:dd:dd:dd:b537
1572c19:dd:c25:c25d:dd:dd:dd:b538/1272c19:dd:c25:c25d:dd:dd:dd:b539
1582c19:dd:c25:c25d:dd:dd:dd:b53a/1272c19:dd:c25:c25d:dd:dd:dd:b53b
1592c19:dd:c25:c25d:dd:dd:dd:b53c/1272c19:dd:c25:c25d:dd:dd:dd:b53d
1602c19:dd:c25:c25d:dd:dd:dd:b53e/1272c19:dd:c25:c25d:dd:dd:dd:b53f
1612c19:dd:c25:c25d:dd:dd:dd:b540/1272c19:dd:c25:c25d:dd:dd:dd:b541
1622c19:dd:c25:c25d:dd:dd:dd:b542/1272c19:dd:c25:c25d:dd:dd:dd:b543
1632c19:dd:c25:c25d:dd:dd:dd:b544/1272c19:dd:c25:c25d:dd:dd:dd:b545
1642c19:dd:c25:c25d:dd:dd:dd:b546/1272c19:dd:c25:c25d:dd:dd:dd:b547
1652c19:dd:c25:c25d:dd:dd:dd:b548/1272c19:dd:c25:c25d:dd:dd:dd:b549
1662c19:dd:c25:c25d:dd:dd:dd:b54a/1272c19:dd:c25:c25d:dd:dd:dd:b54b
1672c19:dd:c25:c25d:dd:dd:dd:b54c/1272c19:dd:c25:c25d:dd:dd:dd:b54d
1682c19:dd:c25:c25d:dd:dd:dd:b54e/1272c19:dd:c25:c25d:dd:dd:dd:b54f
1692c19:dd:c25:c25d:dd:dd:dd:b550/1272c19:dd:c25:c25d:dd:dd:dd:b551
1702c19:dd:c25:c25d:dd:dd:dd:b552/1272c19:dd:c25:c25d:dd:dd:dd:b553
1712c19:dd:c25:c25d:dd:dd:dd:b554/1272c19:dd:c25:c25d:dd:dd:dd:b555
1722c19:dd:c25:c25d:dd:dd:dd:b556/1272c19:dd:c25:c25d:dd:dd:dd:b557
1732c19:dd:c25:c25d:dd:dd:dd:b558/1272c19:dd:c25:c25d:dd:dd:dd:b559
1742c19:dd:c25:c25d:dd:dd:dd:b55a/1272c19:dd:c25:c25d:dd:dd:dd:b55b
1752c19:dd:c25:c25d:dd:dd:dd:b55c/1272c19:dd:c25:c25d:dd:dd:dd:b55d
1762c19:dd:c25:c25d:dd:dd:dd:b55e/1272c19:dd:c25:c25d:dd:dd:dd:b55f
1772c19:dd:c25:c25d:dd:dd:dd:b560/1272c19:dd:c25:c25d:dd:dd:dd:b561
1782c19:dd:c25:c25d:dd:dd:dd:b562/1272c19:dd:c25:c25d:dd:dd:dd:b563
1792c19:dd:c25:c25d:dd:dd:dd:b564/1272c19:dd:c25:c25d:dd:dd:dd:b565
1802c19:dd:c25:c25d:dd:dd:dd:b566/1272c19:dd:c25:c25d:dd:dd:dd:b567
1812c19:dd:c25:c25d:dd:dd:dd:b568/1272c19:dd:c25:c25d:dd:dd:dd:b569
1822c19:dd:c25:c25d:dd:dd:dd:b56a/1272c19:dd:c25:c25d:dd:dd:dd:b56b
1832c19:dd:c25:c25d:dd:dd:dd:b56c/1272c19:dd:c25:c25d:dd:dd:dd:b56d
1842c19:dd:c25:c25d:dd:dd:dd:b56e/1272c19:dd:c25:c25d:dd:dd:dd:b56f
1852c19:dd:c25:c25d:dd:dd:dd:b570/1272c19:dd:c25:c25d:dd:dd:dd:b571
1862c19:dd:c25:c25d:dd:dd:dd:b572/1272c19:dd:c25:c25d:dd:dd:dd:b573
1872c19:dd:c25:c25d:dd:dd:dd:b574/1272c19:dd:c25:c25d:dd:dd:dd:b575
1882c19:dd:c25:c25d:dd:dd:dd:b576/1272c19:dd:c25:c25d:dd:dd:dd:b577
1892c19:dd:c25:c25d:dd:dd:dd:b578/1272c19:dd:c25:c25d:dd:dd:dd:b579
1902c19:dd:c25:c25d:dd:dd:dd:b57a/1272c19:dd:c25:c25d:dd:dd:dd:b57b
1912c19:dd:c25:c25d:dd:dd:dd:b57c/1272c19:dd:c25:c25d:dd:dd:dd:b57d
1922c19:dd:c25:c25d:dd:dd:dd:b57e/1272c19:dd:c25:c25d:dd:dd:dd:b57f
1932c19:dd:c25:c25d:dd:dd:dd:b580/1272c19:dd:c25:c25d:dd:dd:dd:b581
1942c19:dd:c25:c25d:dd:dd:dd:b582/1272c19:dd:c25:c25d:dd:dd:dd:b583
1952c19:dd:c25:c25d:dd:dd:dd:b584/1272c19:dd:c25:c25d:dd:dd:dd:b585
1962c19:dd:c25:c25d:dd:dd:dd:b586/1272c19:dd:c25:c25d:dd:dd:dd:b587
1972c19:dd:c25:c25d:dd:dd:dd:b588/1272c19:dd:c25:c25d:dd:dd:dd:b589
1982c19:dd:c25:c25d:dd:dd:dd:b58a/1272c19:dd:c25:c25d:dd:dd:dd:b58b
1992c19:dd:c25:c25d:dd:dd:dd:b58c/1272c19:dd:c25:c25d:dd:dd:dd:b58d
2002c19:dd:c25:c25d:dd:dd:dd:b58e/1272c19:dd:c25:c25d:dd:dd:dd:b58f
2012c19:dd:c25:c25d:dd:dd:dd:b590/1272c19:dd:c25:c25d:dd:dd:dd:b591
2022c19:dd:c25:c25d:dd:dd:dd:b592/1272c19:dd:c25:c25d:dd:dd:dd:b593
2032c19:dd:c25:c25d:dd:dd:dd:b594/1272c19:dd:c25:c25d:dd:dd:dd:b595
2042c19:dd:c25:c25d:dd:dd:dd:b596/1272c19:dd:c25:c25d:dd:dd:dd:b597
2052c19:dd:c25:c25d:dd:dd:dd:b598/1272c19:dd:c25:c25d:dd:dd:dd:b599
2062c19:dd:c25:c25d:dd:dd:dd:b59a/1272c19:dd:c25:c25d:dd:dd:dd:b59b
2072c19:dd:c25:c25d:dd:dd:dd:b59c/1272c19:dd:c25:c25d:dd:dd:dd:b59d
2082c19:dd:c25:c25d:dd:dd:dd:b59e/1272c19:dd:c25:c25d:dd:dd:dd:b59f
2092c19:dd:c25:c25d:dd:dd:dd:b5a0/1272c19:dd:c25:c25d:dd:dd:dd:b5a1
2102c19:dd:c25:c25d:dd:dd:dd:b5a2/1272c19:dd:c25:c25d:dd:dd:dd:b5a3
2112c19:dd:c25:c25d:dd:dd:dd:b5a4/1272c19:dd:c25:c25d:dd:dd:dd:b5a5
2122c19:dd:c25:c25d:dd:dd:dd:b5a6/1272c19:dd:c25:c25d:dd:dd:dd:b5a7
2132c19:dd:c25:c25d:dd:dd:dd:b5a8/1272c19:dd:c25:c25d:dd:dd:dd:b5a9
2142c19:dd:c25:c25d:dd:dd:dd:b5aa/1272c19:dd:c25:c25d:dd:dd:dd:b5ab
2152c19:dd:c25:c25d:dd:dd:dd:b5ac/1272c19:dd:c25:c25d:dd:dd:dd:b5ad
2162c19:dd:c25:c25d:dd:dd:dd:b5ae/1272c19:dd:c25:c25d:dd:dd:dd:b5af
2172c19:dd:c25:c25d:dd:dd:dd:b5b0/1272c19:dd:c25:c25d:dd:dd:dd:b5b1
2182c19:dd:c25:c25d:dd:dd:dd:b5b2/1272c19:dd:c25:c25d:dd:dd:dd:b5b3
2192c19:dd:c25:c25d:dd:dd:dd:b5b4/1272c19:dd:c25:c25d:dd:dd:dd:b5b5
2202c19:dd:c25:c25d:dd:dd:dd:b5b6/1272c19:dd:c25:c25d:dd:dd:dd:b5b7
2212c19:dd:c25:c25d:dd:dd:dd:b5b8/1272c19:dd:c25:c25d:dd:dd:dd:b5b9
2222c19:dd:c25:c25d:dd:dd:dd:b5ba/1272c19:dd:c25:c25d:dd:dd:dd:b5bb
2232c19:dd:c25:c25d:dd:dd:dd:b5bc/1272c19:dd:c25:c25d:dd:dd:dd:b5bd
2242c19:dd:c25:c25d:dd:dd:dd:b5be/1272c19:dd:c25:c25d:dd:dd:dd:b5bf
2252c19:dd:c25:c25d:dd:dd:dd:b5c0/1272c19:dd:c25:c25d:dd:dd:dd:b5c1
2262c19:dd:c25:c25d:dd:dd:dd:b5c2/1272c19:dd:c25:c25d:dd:dd:dd:b5c3
2272c19:dd:c25:c25d:dd:dd:dd:b5c4/1272c19:dd:c25:c25d:dd:dd:dd:b5c5
2282c19:dd:c25:c25d:dd:dd:dd:b5c6/1272c19:dd:c25:c25d:dd:dd:dd:b5c7
2292c19:dd:c25:c25d:dd:dd:dd:b5c8/1272c19:dd:c25:c25d:dd:dd:dd:b5c9
2302c19:dd:c25:c25d:dd:dd:dd:b5ca/1272c19:dd:c25:c25d:dd:dd:dd:b5cb
2312c19:dd:c25:c25d:dd:dd:dd:b5cc/1272c19:dd:c25:c25d:dd:dd:dd:b5cd
2322c19:dd:c25:c25d:dd:dd:dd:b5ce/1272c19:dd:c25:c25d:dd:dd:dd:b5cf
2332c19:dd:c25:c25d:dd:dd:dd:b5d0/1272c19:dd:c25:c25d:dd:dd:dd:b5d1
2342c19:dd:c25:c25d:dd:dd:dd:b5d2/1272c19:dd:c25:c25d:dd:dd:dd:b5d3
2352c19:dd:c25:c25d:dd:dd:dd:b5d4/1272c19:dd:c25:c25d:dd:dd:dd:b5d5
2362c19:dd:c25:c25d:dd:dd:dd:b5d6/1272c19:dd:c25:c25d:dd:dd:dd:b5d7
2372c19:dd:c25:c25d:dd:dd:dd:b5d8/1272c19:dd:c25:c25d:dd:dd:dd:b5d9
2382c19:dd:c25:c25d:dd:dd:dd:b5da/1272c19:dd:c25:c25d:dd:dd:dd:b5db
2392c19:dd:c25:c25d:dd:dd:dd:b5dc/1272c19:dd:c25:c25d:dd:dd:dd:b5dd
2402c19:dd:c25:c25d:dd:dd:dd:b5de/1272c19:dd:c25:c25d:dd:dd:dd:b5df
2412c19:dd:c25:c25d:dd:dd:dd:b5e0/1272c19:dd:c25:c25d:dd:dd:dd:b5e1
2422c19:dd:c25:c25d:dd:dd:dd:b5e2/1272c19:dd:c25:c25d:dd:dd:dd:b5e3
2432c19:dd:c25:c25d:dd:dd:dd:b5e4/1272c19:dd:c25:c25d:dd:dd:dd:b5e5
2442c19:dd:c25:c25d:dd:dd:dd:b5e6/1272c19:dd:c25:c25d:dd:dd:dd:b5e7
2452c19:dd:c25:c25d:dd:dd:dd:b5e8/1272c19:dd:c25:c25d:dd:dd:dd:b5e9
2462c19:dd:c25:c25d:dd:dd:dd:b5ea/1272c19:dd:c25:c25d:dd:dd:dd:b5eb
2472c19:dd:c25:c25d:dd:dd:dd:b5ec/1272c19:dd:c25:c25d:dd:dd:dd:b5ed
2482c19:dd:c25:c25d:dd:dd:dd:b5ee/1272c19:dd:c25:c25d:dd:dd:dd:b5ef
2492c19:dd:c25:c25d:dd:dd:dd:b5f0/1272c19:dd:c25:c25d:dd:dd:dd:b5f1
2502c19:dd:c25:c25d:dd:dd:dd:b5f2/1272c19:dd:c25:c25d:dd:dd:dd:b5f3
2512c19:dd:c25:c25d:dd:dd:dd:b5f4/1272c19:dd:c25:c25d:dd:dd:dd:b5f5
2522c19:dd:c25:c25d:dd:dd:dd:b5f6/1272c19:dd:c25:c25d:dd:dd:dd:b5f7
2532c19:dd:c25:c25d:dd:dd:dd:b5f8/1272c19:dd:c25:c25d:dd:dd:dd:b5f9
2542c19:dd:c25:c25d:dd:dd:dd:b5fa/1272c19:dd:c25:c25d:dd:dd:dd:b5fb
2552c19:dd:c25:c25d:dd:dd:dd:b5fc/1272c19:dd:c25:c25d:dd:dd:dd:b5fd
2562c19:dd:c25:c25d:dd:dd:dd:b5fe/1272c19:dd:c25:c25d:dd:dd:dd:b5ff

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.