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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:d400/119
First address
2c19:dd:c25:c25d:dd:dd:dd:d400
Last address
2c19:dd:c25:c25d:dd:dd:dd:d5ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:d400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
4.d.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.d.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:d400/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:d400/1272c19:dd:c25:c25d:dd:dd:dd:d401
22c19:dd:c25:c25d:dd:dd:dd:d402/1272c19:dd:c25:c25d:dd:dd:dd:d403
32c19:dd:c25:c25d:dd:dd:dd:d404/1272c19:dd:c25:c25d:dd:dd:dd:d405
42c19:dd:c25:c25d:dd:dd:dd:d406/1272c19:dd:c25:c25d:dd:dd:dd:d407
52c19:dd:c25:c25d:dd:dd:dd:d408/1272c19:dd:c25:c25d:dd:dd:dd:d409
62c19:dd:c25:c25d:dd:dd:dd:d40a/1272c19:dd:c25:c25d:dd:dd:dd:d40b
72c19:dd:c25:c25d:dd:dd:dd:d40c/1272c19:dd:c25:c25d:dd:dd:dd:d40d
82c19:dd:c25:c25d:dd:dd:dd:d40e/1272c19:dd:c25:c25d:dd:dd:dd:d40f
92c19:dd:c25:c25d:dd:dd:dd:d410/1272c19:dd:c25:c25d:dd:dd:dd:d411
102c19:dd:c25:c25d:dd:dd:dd:d412/1272c19:dd:c25:c25d:dd:dd:dd:d413
112c19:dd:c25:c25d:dd:dd:dd:d414/1272c19:dd:c25:c25d:dd:dd:dd:d415
122c19:dd:c25:c25d:dd:dd:dd:d416/1272c19:dd:c25:c25d:dd:dd:dd:d417
132c19:dd:c25:c25d:dd:dd:dd:d418/1272c19:dd:c25:c25d:dd:dd:dd:d419
142c19:dd:c25:c25d:dd:dd:dd:d41a/1272c19:dd:c25:c25d:dd:dd:dd:d41b
152c19:dd:c25:c25d:dd:dd:dd:d41c/1272c19:dd:c25:c25d:dd:dd:dd:d41d
162c19:dd:c25:c25d:dd:dd:dd:d41e/1272c19:dd:c25:c25d:dd:dd:dd:d41f
172c19:dd:c25:c25d:dd:dd:dd:d420/1272c19:dd:c25:c25d:dd:dd:dd:d421
182c19:dd:c25:c25d:dd:dd:dd:d422/1272c19:dd:c25:c25d:dd:dd:dd:d423
192c19:dd:c25:c25d:dd:dd:dd:d424/1272c19:dd:c25:c25d:dd:dd:dd:d425
202c19:dd:c25:c25d:dd:dd:dd:d426/1272c19:dd:c25:c25d:dd:dd:dd:d427
212c19:dd:c25:c25d:dd:dd:dd:d428/1272c19:dd:c25:c25d:dd:dd:dd:d429
222c19:dd:c25:c25d:dd:dd:dd:d42a/1272c19:dd:c25:c25d:dd:dd:dd:d42b
232c19:dd:c25:c25d:dd:dd:dd:d42c/1272c19:dd:c25:c25d:dd:dd:dd:d42d
242c19:dd:c25:c25d:dd:dd:dd:d42e/1272c19:dd:c25:c25d:dd:dd:dd:d42f
252c19:dd:c25:c25d:dd:dd:dd:d430/1272c19:dd:c25:c25d:dd:dd:dd:d431
262c19:dd:c25:c25d:dd:dd:dd:d432/1272c19:dd:c25:c25d:dd:dd:dd:d433
272c19:dd:c25:c25d:dd:dd:dd:d434/1272c19:dd:c25:c25d:dd:dd:dd:d435
282c19:dd:c25:c25d:dd:dd:dd:d436/1272c19:dd:c25:c25d:dd:dd:dd:d437
292c19:dd:c25:c25d:dd:dd:dd:d438/1272c19:dd:c25:c25d:dd:dd:dd:d439
302c19:dd:c25:c25d:dd:dd:dd:d43a/1272c19:dd:c25:c25d:dd:dd:dd:d43b
312c19:dd:c25:c25d:dd:dd:dd:d43c/1272c19:dd:c25:c25d:dd:dd:dd:d43d
322c19:dd:c25:c25d:dd:dd:dd:d43e/1272c19:dd:c25:c25d:dd:dd:dd:d43f
332c19:dd:c25:c25d:dd:dd:dd:d440/1272c19:dd:c25:c25d:dd:dd:dd:d441
342c19:dd:c25:c25d:dd:dd:dd:d442/1272c19:dd:c25:c25d:dd:dd:dd:d443
352c19:dd:c25:c25d:dd:dd:dd:d444/1272c19:dd:c25:c25d:dd:dd:dd:d445
362c19:dd:c25:c25d:dd:dd:dd:d446/1272c19:dd:c25:c25d:dd:dd:dd:d447
372c19:dd:c25:c25d:dd:dd:dd:d448/1272c19:dd:c25:c25d:dd:dd:dd:d449
382c19:dd:c25:c25d:dd:dd:dd:d44a/1272c19:dd:c25:c25d:dd:dd:dd:d44b
392c19:dd:c25:c25d:dd:dd:dd:d44c/1272c19:dd:c25:c25d:dd:dd:dd:d44d
402c19:dd:c25:c25d:dd:dd:dd:d44e/1272c19:dd:c25:c25d:dd:dd:dd:d44f
412c19:dd:c25:c25d:dd:dd:dd:d450/1272c19:dd:c25:c25d:dd:dd:dd:d451
422c19:dd:c25:c25d:dd:dd:dd:d452/1272c19:dd:c25:c25d:dd:dd:dd:d453
432c19:dd:c25:c25d:dd:dd:dd:d454/1272c19:dd:c25:c25d:dd:dd:dd:d455
442c19:dd:c25:c25d:dd:dd:dd:d456/1272c19:dd:c25:c25d:dd:dd:dd:d457
452c19:dd:c25:c25d:dd:dd:dd:d458/1272c19:dd:c25:c25d:dd:dd:dd:d459
462c19:dd:c25:c25d:dd:dd:dd:d45a/1272c19:dd:c25:c25d:dd:dd:dd:d45b
472c19:dd:c25:c25d:dd:dd:dd:d45c/1272c19:dd:c25:c25d:dd:dd:dd:d45d
482c19:dd:c25:c25d:dd:dd:dd:d45e/1272c19:dd:c25:c25d:dd:dd:dd:d45f
492c19:dd:c25:c25d:dd:dd:dd:d460/1272c19:dd:c25:c25d:dd:dd:dd:d461
502c19:dd:c25:c25d:dd:dd:dd:d462/1272c19:dd:c25:c25d:dd:dd:dd:d463
512c19:dd:c25:c25d:dd:dd:dd:d464/1272c19:dd:c25:c25d:dd:dd:dd:d465
522c19:dd:c25:c25d:dd:dd:dd:d466/1272c19:dd:c25:c25d:dd:dd:dd:d467
532c19:dd:c25:c25d:dd:dd:dd:d468/1272c19:dd:c25:c25d:dd:dd:dd:d469
542c19:dd:c25:c25d:dd:dd:dd:d46a/1272c19:dd:c25:c25d:dd:dd:dd:d46b
552c19:dd:c25:c25d:dd:dd:dd:d46c/1272c19:dd:c25:c25d:dd:dd:dd:d46d
562c19:dd:c25:c25d:dd:dd:dd:d46e/1272c19:dd:c25:c25d:dd:dd:dd:d46f
572c19:dd:c25:c25d:dd:dd:dd:d470/1272c19:dd:c25:c25d:dd:dd:dd:d471
582c19:dd:c25:c25d:dd:dd:dd:d472/1272c19:dd:c25:c25d:dd:dd:dd:d473
592c19:dd:c25:c25d:dd:dd:dd:d474/1272c19:dd:c25:c25d:dd:dd:dd:d475
602c19:dd:c25:c25d:dd:dd:dd:d476/1272c19:dd:c25:c25d:dd:dd:dd:d477
612c19:dd:c25:c25d:dd:dd:dd:d478/1272c19:dd:c25:c25d:dd:dd:dd:d479
622c19:dd:c25:c25d:dd:dd:dd:d47a/1272c19:dd:c25:c25d:dd:dd:dd:d47b
632c19:dd:c25:c25d:dd:dd:dd:d47c/1272c19:dd:c25:c25d:dd:dd:dd:d47d
642c19:dd:c25:c25d:dd:dd:dd:d47e/1272c19:dd:c25:c25d:dd:dd:dd:d47f
652c19:dd:c25:c25d:dd:dd:dd:d480/1272c19:dd:c25:c25d:dd:dd:dd:d481
662c19:dd:c25:c25d:dd:dd:dd:d482/1272c19:dd:c25:c25d:dd:dd:dd:d483
672c19:dd:c25:c25d:dd:dd:dd:d484/1272c19:dd:c25:c25d:dd:dd:dd:d485
682c19:dd:c25:c25d:dd:dd:dd:d486/1272c19:dd:c25:c25d:dd:dd:dd:d487
692c19:dd:c25:c25d:dd:dd:dd:d488/1272c19:dd:c25:c25d:dd:dd:dd:d489
702c19:dd:c25:c25d:dd:dd:dd:d48a/1272c19:dd:c25:c25d:dd:dd:dd:d48b
712c19:dd:c25:c25d:dd:dd:dd:d48c/1272c19:dd:c25:c25d:dd:dd:dd:d48d
722c19:dd:c25:c25d:dd:dd:dd:d48e/1272c19:dd:c25:c25d:dd:dd:dd:d48f
732c19:dd:c25:c25d:dd:dd:dd:d490/1272c19:dd:c25:c25d:dd:dd:dd:d491
742c19:dd:c25:c25d:dd:dd:dd:d492/1272c19:dd:c25:c25d:dd:dd:dd:d493
752c19:dd:c25:c25d:dd:dd:dd:d494/1272c19:dd:c25:c25d:dd:dd:dd:d495
762c19:dd:c25:c25d:dd:dd:dd:d496/1272c19:dd:c25:c25d:dd:dd:dd:d497
772c19:dd:c25:c25d:dd:dd:dd:d498/1272c19:dd:c25:c25d:dd:dd:dd:d499
782c19:dd:c25:c25d:dd:dd:dd:d49a/1272c19:dd:c25:c25d:dd:dd:dd:d49b
792c19:dd:c25:c25d:dd:dd:dd:d49c/1272c19:dd:c25:c25d:dd:dd:dd:d49d
802c19:dd:c25:c25d:dd:dd:dd:d49e/1272c19:dd:c25:c25d:dd:dd:dd:d49f
812c19:dd:c25:c25d:dd:dd:dd:d4a0/1272c19:dd:c25:c25d:dd:dd:dd:d4a1
822c19:dd:c25:c25d:dd:dd:dd:d4a2/1272c19:dd:c25:c25d:dd:dd:dd:d4a3
832c19:dd:c25:c25d:dd:dd:dd:d4a4/1272c19:dd:c25:c25d:dd:dd:dd:d4a5
842c19:dd:c25:c25d:dd:dd:dd:d4a6/1272c19:dd:c25:c25d:dd:dd:dd:d4a7
852c19:dd:c25:c25d:dd:dd:dd:d4a8/1272c19:dd:c25:c25d:dd:dd:dd:d4a9
862c19:dd:c25:c25d:dd:dd:dd:d4aa/1272c19:dd:c25:c25d:dd:dd:dd:d4ab
872c19:dd:c25:c25d:dd:dd:dd:d4ac/1272c19:dd:c25:c25d:dd:dd:dd:d4ad
882c19:dd:c25:c25d:dd:dd:dd:d4ae/1272c19:dd:c25:c25d:dd:dd:dd:d4af
892c19:dd:c25:c25d:dd:dd:dd:d4b0/1272c19:dd:c25:c25d:dd:dd:dd:d4b1
902c19:dd:c25:c25d:dd:dd:dd:d4b2/1272c19:dd:c25:c25d:dd:dd:dd:d4b3
912c19:dd:c25:c25d:dd:dd:dd:d4b4/1272c19:dd:c25:c25d:dd:dd:dd:d4b5
922c19:dd:c25:c25d:dd:dd:dd:d4b6/1272c19:dd:c25:c25d:dd:dd:dd:d4b7
932c19:dd:c25:c25d:dd:dd:dd:d4b8/1272c19:dd:c25:c25d:dd:dd:dd:d4b9
942c19:dd:c25:c25d:dd:dd:dd:d4ba/1272c19:dd:c25:c25d:dd:dd:dd:d4bb
952c19:dd:c25:c25d:dd:dd:dd:d4bc/1272c19:dd:c25:c25d:dd:dd:dd:d4bd
962c19:dd:c25:c25d:dd:dd:dd:d4be/1272c19:dd:c25:c25d:dd:dd:dd:d4bf
972c19:dd:c25:c25d:dd:dd:dd:d4c0/1272c19:dd:c25:c25d:dd:dd:dd:d4c1
982c19:dd:c25:c25d:dd:dd:dd:d4c2/1272c19:dd:c25:c25d:dd:dd:dd:d4c3
992c19:dd:c25:c25d:dd:dd:dd:d4c4/1272c19:dd:c25:c25d:dd:dd:dd:d4c5
1002c19:dd:c25:c25d:dd:dd:dd:d4c6/1272c19:dd:c25:c25d:dd:dd:dd:d4c7
1012c19:dd:c25:c25d:dd:dd:dd:d4c8/1272c19:dd:c25:c25d:dd:dd:dd:d4c9
1022c19:dd:c25:c25d:dd:dd:dd:d4ca/1272c19:dd:c25:c25d:dd:dd:dd:d4cb
1032c19:dd:c25:c25d:dd:dd:dd:d4cc/1272c19:dd:c25:c25d:dd:dd:dd:d4cd
1042c19:dd:c25:c25d:dd:dd:dd:d4ce/1272c19:dd:c25:c25d:dd:dd:dd:d4cf
1052c19:dd:c25:c25d:dd:dd:dd:d4d0/1272c19:dd:c25:c25d:dd:dd:dd:d4d1
1062c19:dd:c25:c25d:dd:dd:dd:d4d2/1272c19:dd:c25:c25d:dd:dd:dd:d4d3
1072c19:dd:c25:c25d:dd:dd:dd:d4d4/1272c19:dd:c25:c25d:dd:dd:dd:d4d5
1082c19:dd:c25:c25d:dd:dd:dd:d4d6/1272c19:dd:c25:c25d:dd:dd:dd:d4d7
1092c19:dd:c25:c25d:dd:dd:dd:d4d8/1272c19:dd:c25:c25d:dd:dd:dd:d4d9
1102c19:dd:c25:c25d:dd:dd:dd:d4da/1272c19:dd:c25:c25d:dd:dd:dd:d4db
1112c19:dd:c25:c25d:dd:dd:dd:d4dc/1272c19:dd:c25:c25d:dd:dd:dd:d4dd
1122c19:dd:c25:c25d:dd:dd:dd:d4de/1272c19:dd:c25:c25d:dd:dd:dd:d4df
1132c19:dd:c25:c25d:dd:dd:dd:d4e0/1272c19:dd:c25:c25d:dd:dd:dd:d4e1
1142c19:dd:c25:c25d:dd:dd:dd:d4e2/1272c19:dd:c25:c25d:dd:dd:dd:d4e3
1152c19:dd:c25:c25d:dd:dd:dd:d4e4/1272c19:dd:c25:c25d:dd:dd:dd:d4e5
1162c19:dd:c25:c25d:dd:dd:dd:d4e6/1272c19:dd:c25:c25d:dd:dd:dd:d4e7
1172c19:dd:c25:c25d:dd:dd:dd:d4e8/1272c19:dd:c25:c25d:dd:dd:dd:d4e9
1182c19:dd:c25:c25d:dd:dd:dd:d4ea/1272c19:dd:c25:c25d:dd:dd:dd:d4eb
1192c19:dd:c25:c25d:dd:dd:dd:d4ec/1272c19:dd:c25:c25d:dd:dd:dd:d4ed
1202c19:dd:c25:c25d:dd:dd:dd:d4ee/1272c19:dd:c25:c25d:dd:dd:dd:d4ef
1212c19:dd:c25:c25d:dd:dd:dd:d4f0/1272c19:dd:c25:c25d:dd:dd:dd:d4f1
1222c19:dd:c25:c25d:dd:dd:dd:d4f2/1272c19:dd:c25:c25d:dd:dd:dd:d4f3
1232c19:dd:c25:c25d:dd:dd:dd:d4f4/1272c19:dd:c25:c25d:dd:dd:dd:d4f5
1242c19:dd:c25:c25d:dd:dd:dd:d4f6/1272c19:dd:c25:c25d:dd:dd:dd:d4f7
1252c19:dd:c25:c25d:dd:dd:dd:d4f8/1272c19:dd:c25:c25d:dd:dd:dd:d4f9
1262c19:dd:c25:c25d:dd:dd:dd:d4fa/1272c19:dd:c25:c25d:dd:dd:dd:d4fb
1272c19:dd:c25:c25d:dd:dd:dd:d4fc/1272c19:dd:c25:c25d:dd:dd:dd:d4fd
1282c19:dd:c25:c25d:dd:dd:dd:d4fe/1272c19:dd:c25:c25d:dd:dd:dd:d4ff
1292c19:dd:c25:c25d:dd:dd:dd:d500/1272c19:dd:c25:c25d:dd:dd:dd:d501
1302c19:dd:c25:c25d:dd:dd:dd:d502/1272c19:dd:c25:c25d:dd:dd:dd:d503
1312c19:dd:c25:c25d:dd:dd:dd:d504/1272c19:dd:c25:c25d:dd:dd:dd:d505
1322c19:dd:c25:c25d:dd:dd:dd:d506/1272c19:dd:c25:c25d:dd:dd:dd:d507
1332c19:dd:c25:c25d:dd:dd:dd:d508/1272c19:dd:c25:c25d:dd:dd:dd:d509
1342c19:dd:c25:c25d:dd:dd:dd:d50a/1272c19:dd:c25:c25d:dd:dd:dd:d50b
1352c19:dd:c25:c25d:dd:dd:dd:d50c/1272c19:dd:c25:c25d:dd:dd:dd:d50d
1362c19:dd:c25:c25d:dd:dd:dd:d50e/1272c19:dd:c25:c25d:dd:dd:dd:d50f
1372c19:dd:c25:c25d:dd:dd:dd:d510/1272c19:dd:c25:c25d:dd:dd:dd:d511
1382c19:dd:c25:c25d:dd:dd:dd:d512/1272c19:dd:c25:c25d:dd:dd:dd:d513
1392c19:dd:c25:c25d:dd:dd:dd:d514/1272c19:dd:c25:c25d:dd:dd:dd:d515
1402c19:dd:c25:c25d:dd:dd:dd:d516/1272c19:dd:c25:c25d:dd:dd:dd:d517
1412c19:dd:c25:c25d:dd:dd:dd:d518/1272c19:dd:c25:c25d:dd:dd:dd:d519
1422c19:dd:c25:c25d:dd:dd:dd:d51a/1272c19:dd:c25:c25d:dd:dd:dd:d51b
1432c19:dd:c25:c25d:dd:dd:dd:d51c/1272c19:dd:c25:c25d:dd:dd:dd:d51d
1442c19:dd:c25:c25d:dd:dd:dd:d51e/1272c19:dd:c25:c25d:dd:dd:dd:d51f
1452c19:dd:c25:c25d:dd:dd:dd:d520/1272c19:dd:c25:c25d:dd:dd:dd:d521
1462c19:dd:c25:c25d:dd:dd:dd:d522/1272c19:dd:c25:c25d:dd:dd:dd:d523
1472c19:dd:c25:c25d:dd:dd:dd:d524/1272c19:dd:c25:c25d:dd:dd:dd:d525
1482c19:dd:c25:c25d:dd:dd:dd:d526/1272c19:dd:c25:c25d:dd:dd:dd:d527
1492c19:dd:c25:c25d:dd:dd:dd:d528/1272c19:dd:c25:c25d:dd:dd:dd:d529
1502c19:dd:c25:c25d:dd:dd:dd:d52a/1272c19:dd:c25:c25d:dd:dd:dd:d52b
1512c19:dd:c25:c25d:dd:dd:dd:d52c/1272c19:dd:c25:c25d:dd:dd:dd:d52d
1522c19:dd:c25:c25d:dd:dd:dd:d52e/1272c19:dd:c25:c25d:dd:dd:dd:d52f
1532c19:dd:c25:c25d:dd:dd:dd:d530/1272c19:dd:c25:c25d:dd:dd:dd:d531
1542c19:dd:c25:c25d:dd:dd:dd:d532/1272c19:dd:c25:c25d:dd:dd:dd:d533
1552c19:dd:c25:c25d:dd:dd:dd:d534/1272c19:dd:c25:c25d:dd:dd:dd:d535
1562c19:dd:c25:c25d:dd:dd:dd:d536/1272c19:dd:c25:c25d:dd:dd:dd:d537
1572c19:dd:c25:c25d:dd:dd:dd:d538/1272c19:dd:c25:c25d:dd:dd:dd:d539
1582c19:dd:c25:c25d:dd:dd:dd:d53a/1272c19:dd:c25:c25d:dd:dd:dd:d53b
1592c19:dd:c25:c25d:dd:dd:dd:d53c/1272c19:dd:c25:c25d:dd:dd:dd:d53d
1602c19:dd:c25:c25d:dd:dd:dd:d53e/1272c19:dd:c25:c25d:dd:dd:dd:d53f
1612c19:dd:c25:c25d:dd:dd:dd:d540/1272c19:dd:c25:c25d:dd:dd:dd:d541
1622c19:dd:c25:c25d:dd:dd:dd:d542/1272c19:dd:c25:c25d:dd:dd:dd:d543
1632c19:dd:c25:c25d:dd:dd:dd:d544/1272c19:dd:c25:c25d:dd:dd:dd:d545
1642c19:dd:c25:c25d:dd:dd:dd:d546/1272c19:dd:c25:c25d:dd:dd:dd:d547
1652c19:dd:c25:c25d:dd:dd:dd:d548/1272c19:dd:c25:c25d:dd:dd:dd:d549
1662c19:dd:c25:c25d:dd:dd:dd:d54a/1272c19:dd:c25:c25d:dd:dd:dd:d54b
1672c19:dd:c25:c25d:dd:dd:dd:d54c/1272c19:dd:c25:c25d:dd:dd:dd:d54d
1682c19:dd:c25:c25d:dd:dd:dd:d54e/1272c19:dd:c25:c25d:dd:dd:dd:d54f
1692c19:dd:c25:c25d:dd:dd:dd:d550/1272c19:dd:c25:c25d:dd:dd:dd:d551
1702c19:dd:c25:c25d:dd:dd:dd:d552/1272c19:dd:c25:c25d:dd:dd:dd:d553
1712c19:dd:c25:c25d:dd:dd:dd:d554/1272c19:dd:c25:c25d:dd:dd:dd:d555
1722c19:dd:c25:c25d:dd:dd:dd:d556/1272c19:dd:c25:c25d:dd:dd:dd:d557
1732c19:dd:c25:c25d:dd:dd:dd:d558/1272c19:dd:c25:c25d:dd:dd:dd:d559
1742c19:dd:c25:c25d:dd:dd:dd:d55a/1272c19:dd:c25:c25d:dd:dd:dd:d55b
1752c19:dd:c25:c25d:dd:dd:dd:d55c/1272c19:dd:c25:c25d:dd:dd:dd:d55d
1762c19:dd:c25:c25d:dd:dd:dd:d55e/1272c19:dd:c25:c25d:dd:dd:dd:d55f
1772c19:dd:c25:c25d:dd:dd:dd:d560/1272c19:dd:c25:c25d:dd:dd:dd:d561
1782c19:dd:c25:c25d:dd:dd:dd:d562/1272c19:dd:c25:c25d:dd:dd:dd:d563
1792c19:dd:c25:c25d:dd:dd:dd:d564/1272c19:dd:c25:c25d:dd:dd:dd:d565
1802c19:dd:c25:c25d:dd:dd:dd:d566/1272c19:dd:c25:c25d:dd:dd:dd:d567
1812c19:dd:c25:c25d:dd:dd:dd:d568/1272c19:dd:c25:c25d:dd:dd:dd:d569
1822c19:dd:c25:c25d:dd:dd:dd:d56a/1272c19:dd:c25:c25d:dd:dd:dd:d56b
1832c19:dd:c25:c25d:dd:dd:dd:d56c/1272c19:dd:c25:c25d:dd:dd:dd:d56d
1842c19:dd:c25:c25d:dd:dd:dd:d56e/1272c19:dd:c25:c25d:dd:dd:dd:d56f
1852c19:dd:c25:c25d:dd:dd:dd:d570/1272c19:dd:c25:c25d:dd:dd:dd:d571
1862c19:dd:c25:c25d:dd:dd:dd:d572/1272c19:dd:c25:c25d:dd:dd:dd:d573
1872c19:dd:c25:c25d:dd:dd:dd:d574/1272c19:dd:c25:c25d:dd:dd:dd:d575
1882c19:dd:c25:c25d:dd:dd:dd:d576/1272c19:dd:c25:c25d:dd:dd:dd:d577
1892c19:dd:c25:c25d:dd:dd:dd:d578/1272c19:dd:c25:c25d:dd:dd:dd:d579
1902c19:dd:c25:c25d:dd:dd:dd:d57a/1272c19:dd:c25:c25d:dd:dd:dd:d57b
1912c19:dd:c25:c25d:dd:dd:dd:d57c/1272c19:dd:c25:c25d:dd:dd:dd:d57d
1922c19:dd:c25:c25d:dd:dd:dd:d57e/1272c19:dd:c25:c25d:dd:dd:dd:d57f
1932c19:dd:c25:c25d:dd:dd:dd:d580/1272c19:dd:c25:c25d:dd:dd:dd:d581
1942c19:dd:c25:c25d:dd:dd:dd:d582/1272c19:dd:c25:c25d:dd:dd:dd:d583
1952c19:dd:c25:c25d:dd:dd:dd:d584/1272c19:dd:c25:c25d:dd:dd:dd:d585
1962c19:dd:c25:c25d:dd:dd:dd:d586/1272c19:dd:c25:c25d:dd:dd:dd:d587
1972c19:dd:c25:c25d:dd:dd:dd:d588/1272c19:dd:c25:c25d:dd:dd:dd:d589
1982c19:dd:c25:c25d:dd:dd:dd:d58a/1272c19:dd:c25:c25d:dd:dd:dd:d58b
1992c19:dd:c25:c25d:dd:dd:dd:d58c/1272c19:dd:c25:c25d:dd:dd:dd:d58d
2002c19:dd:c25:c25d:dd:dd:dd:d58e/1272c19:dd:c25:c25d:dd:dd:dd:d58f
2012c19:dd:c25:c25d:dd:dd:dd:d590/1272c19:dd:c25:c25d:dd:dd:dd:d591
2022c19:dd:c25:c25d:dd:dd:dd:d592/1272c19:dd:c25:c25d:dd:dd:dd:d593
2032c19:dd:c25:c25d:dd:dd:dd:d594/1272c19:dd:c25:c25d:dd:dd:dd:d595
2042c19:dd:c25:c25d:dd:dd:dd:d596/1272c19:dd:c25:c25d:dd:dd:dd:d597
2052c19:dd:c25:c25d:dd:dd:dd:d598/1272c19:dd:c25:c25d:dd:dd:dd:d599
2062c19:dd:c25:c25d:dd:dd:dd:d59a/1272c19:dd:c25:c25d:dd:dd:dd:d59b
2072c19:dd:c25:c25d:dd:dd:dd:d59c/1272c19:dd:c25:c25d:dd:dd:dd:d59d
2082c19:dd:c25:c25d:dd:dd:dd:d59e/1272c19:dd:c25:c25d:dd:dd:dd:d59f
2092c19:dd:c25:c25d:dd:dd:dd:d5a0/1272c19:dd:c25:c25d:dd:dd:dd:d5a1
2102c19:dd:c25:c25d:dd:dd:dd:d5a2/1272c19:dd:c25:c25d:dd:dd:dd:d5a3
2112c19:dd:c25:c25d:dd:dd:dd:d5a4/1272c19:dd:c25:c25d:dd:dd:dd:d5a5
2122c19:dd:c25:c25d:dd:dd:dd:d5a6/1272c19:dd:c25:c25d:dd:dd:dd:d5a7
2132c19:dd:c25:c25d:dd:dd:dd:d5a8/1272c19:dd:c25:c25d:dd:dd:dd:d5a9
2142c19:dd:c25:c25d:dd:dd:dd:d5aa/1272c19:dd:c25:c25d:dd:dd:dd:d5ab
2152c19:dd:c25:c25d:dd:dd:dd:d5ac/1272c19:dd:c25:c25d:dd:dd:dd:d5ad
2162c19:dd:c25:c25d:dd:dd:dd:d5ae/1272c19:dd:c25:c25d:dd:dd:dd:d5af
2172c19:dd:c25:c25d:dd:dd:dd:d5b0/1272c19:dd:c25:c25d:dd:dd:dd:d5b1
2182c19:dd:c25:c25d:dd:dd:dd:d5b2/1272c19:dd:c25:c25d:dd:dd:dd:d5b3
2192c19:dd:c25:c25d:dd:dd:dd:d5b4/1272c19:dd:c25:c25d:dd:dd:dd:d5b5
2202c19:dd:c25:c25d:dd:dd:dd:d5b6/1272c19:dd:c25:c25d:dd:dd:dd:d5b7
2212c19:dd:c25:c25d:dd:dd:dd:d5b8/1272c19:dd:c25:c25d:dd:dd:dd:d5b9
2222c19:dd:c25:c25d:dd:dd:dd:d5ba/1272c19:dd:c25:c25d:dd:dd:dd:d5bb
2232c19:dd:c25:c25d:dd:dd:dd:d5bc/1272c19:dd:c25:c25d:dd:dd:dd:d5bd
2242c19:dd:c25:c25d:dd:dd:dd:d5be/1272c19:dd:c25:c25d:dd:dd:dd:d5bf
2252c19:dd:c25:c25d:dd:dd:dd:d5c0/1272c19:dd:c25:c25d:dd:dd:dd:d5c1
2262c19:dd:c25:c25d:dd:dd:dd:d5c2/1272c19:dd:c25:c25d:dd:dd:dd:d5c3
2272c19:dd:c25:c25d:dd:dd:dd:d5c4/1272c19:dd:c25:c25d:dd:dd:dd:d5c5
2282c19:dd:c25:c25d:dd:dd:dd:d5c6/1272c19:dd:c25:c25d:dd:dd:dd:d5c7
2292c19:dd:c25:c25d:dd:dd:dd:d5c8/1272c19:dd:c25:c25d:dd:dd:dd:d5c9
2302c19:dd:c25:c25d:dd:dd:dd:d5ca/1272c19:dd:c25:c25d:dd:dd:dd:d5cb
2312c19:dd:c25:c25d:dd:dd:dd:d5cc/1272c19:dd:c25:c25d:dd:dd:dd:d5cd
2322c19:dd:c25:c25d:dd:dd:dd:d5ce/1272c19:dd:c25:c25d:dd:dd:dd:d5cf
2332c19:dd:c25:c25d:dd:dd:dd:d5d0/1272c19:dd:c25:c25d:dd:dd:dd:d5d1
2342c19:dd:c25:c25d:dd:dd:dd:d5d2/1272c19:dd:c25:c25d:dd:dd:dd:d5d3
2352c19:dd:c25:c25d:dd:dd:dd:d5d4/1272c19:dd:c25:c25d:dd:dd:dd:d5d5
2362c19:dd:c25:c25d:dd:dd:dd:d5d6/1272c19:dd:c25:c25d:dd:dd:dd:d5d7
2372c19:dd:c25:c25d:dd:dd:dd:d5d8/1272c19:dd:c25:c25d:dd:dd:dd:d5d9
2382c19:dd:c25:c25d:dd:dd:dd:d5da/1272c19:dd:c25:c25d:dd:dd:dd:d5db
2392c19:dd:c25:c25d:dd:dd:dd:d5dc/1272c19:dd:c25:c25d:dd:dd:dd:d5dd
2402c19:dd:c25:c25d:dd:dd:dd:d5de/1272c19:dd:c25:c25d:dd:dd:dd:d5df
2412c19:dd:c25:c25d:dd:dd:dd:d5e0/1272c19:dd:c25:c25d:dd:dd:dd:d5e1
2422c19:dd:c25:c25d:dd:dd:dd:d5e2/1272c19:dd:c25:c25d:dd:dd:dd:d5e3
2432c19:dd:c25:c25d:dd:dd:dd:d5e4/1272c19:dd:c25:c25d:dd:dd:dd:d5e5
2442c19:dd:c25:c25d:dd:dd:dd:d5e6/1272c19:dd:c25:c25d:dd:dd:dd:d5e7
2452c19:dd:c25:c25d:dd:dd:dd:d5e8/1272c19:dd:c25:c25d:dd:dd:dd:d5e9
2462c19:dd:c25:c25d:dd:dd:dd:d5ea/1272c19:dd:c25:c25d:dd:dd:dd:d5eb
2472c19:dd:c25:c25d:dd:dd:dd:d5ec/1272c19:dd:c25:c25d:dd:dd:dd:d5ed
2482c19:dd:c25:c25d:dd:dd:dd:d5ee/1272c19:dd:c25:c25d:dd:dd:dd:d5ef
2492c19:dd:c25:c25d:dd:dd:dd:d5f0/1272c19:dd:c25:c25d:dd:dd:dd:d5f1
2502c19:dd:c25:c25d:dd:dd:dd:d5f2/1272c19:dd:c25:c25d:dd:dd:dd:d5f3
2512c19:dd:c25:c25d:dd:dd:dd:d5f4/1272c19:dd:c25:c25d:dd:dd:dd:d5f5
2522c19:dd:c25:c25d:dd:dd:dd:d5f6/1272c19:dd:c25:c25d:dd:dd:dd:d5f7
2532c19:dd:c25:c25d:dd:dd:dd:d5f8/1272c19:dd:c25:c25d:dd:dd:dd:d5f9
2542c19:dd:c25:c25d:dd:dd:dd:d5fa/1272c19:dd:c25:c25d:dd:dd:dd:d5fb
2552c19:dd:c25:c25d:dd:dd:dd:d5fc/1272c19:dd:c25:c25d:dd:dd:dd:d5fd
2562c19:dd:c25:c25d:dd:dd:dd:d5fe/1272c19:dd:c25:c25d:dd:dd:dd:d5ff

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.