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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:400/119
First address
2c19:dd:d9:dd:c25:c25:94de:400
Last address
2c19:dd:d9:dd:c25:c25:94de:5ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:0400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
4.0.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
5.0.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:400/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:400/1272c19:dd:d9:dd:c25:c25:94de:401
22c19:dd:d9:dd:c25:c25:94de:402/1272c19:dd:d9:dd:c25:c25:94de:403
32c19:dd:d9:dd:c25:c25:94de:404/1272c19:dd:d9:dd:c25:c25:94de:405
42c19:dd:d9:dd:c25:c25:94de:406/1272c19:dd:d9:dd:c25:c25:94de:407
52c19:dd:d9:dd:c25:c25:94de:408/1272c19:dd:d9:dd:c25:c25:94de:409
62c19:dd:d9:dd:c25:c25:94de:40a/1272c19:dd:d9:dd:c25:c25:94de:40b
72c19:dd:d9:dd:c25:c25:94de:40c/1272c19:dd:d9:dd:c25:c25:94de:40d
82c19:dd:d9:dd:c25:c25:94de:40e/1272c19:dd:d9:dd:c25:c25:94de:40f
92c19:dd:d9:dd:c25:c25:94de:410/1272c19:dd:d9:dd:c25:c25:94de:411
102c19:dd:d9:dd:c25:c25:94de:412/1272c19:dd:d9:dd:c25:c25:94de:413
112c19:dd:d9:dd:c25:c25:94de:414/1272c19:dd:d9:dd:c25:c25:94de:415
122c19:dd:d9:dd:c25:c25:94de:416/1272c19:dd:d9:dd:c25:c25:94de:417
132c19:dd:d9:dd:c25:c25:94de:418/1272c19:dd:d9:dd:c25:c25:94de:419
142c19:dd:d9:dd:c25:c25:94de:41a/1272c19:dd:d9:dd:c25:c25:94de:41b
152c19:dd:d9:dd:c25:c25:94de:41c/1272c19:dd:d9:dd:c25:c25:94de:41d
162c19:dd:d9:dd:c25:c25:94de:41e/1272c19:dd:d9:dd:c25:c25:94de:41f
172c19:dd:d9:dd:c25:c25:94de:420/1272c19:dd:d9:dd:c25:c25:94de:421
182c19:dd:d9:dd:c25:c25:94de:422/1272c19:dd:d9:dd:c25:c25:94de:423
192c19:dd:d9:dd:c25:c25:94de:424/1272c19:dd:d9:dd:c25:c25:94de:425
202c19:dd:d9:dd:c25:c25:94de:426/1272c19:dd:d9:dd:c25:c25:94de:427
212c19:dd:d9:dd:c25:c25:94de:428/1272c19:dd:d9:dd:c25:c25:94de:429
222c19:dd:d9:dd:c25:c25:94de:42a/1272c19:dd:d9:dd:c25:c25:94de:42b
232c19:dd:d9:dd:c25:c25:94de:42c/1272c19:dd:d9:dd:c25:c25:94de:42d
242c19:dd:d9:dd:c25:c25:94de:42e/1272c19:dd:d9:dd:c25:c25:94de:42f
252c19:dd:d9:dd:c25:c25:94de:430/1272c19:dd:d9:dd:c25:c25:94de:431
262c19:dd:d9:dd:c25:c25:94de:432/1272c19:dd:d9:dd:c25:c25:94de:433
272c19:dd:d9:dd:c25:c25:94de:434/1272c19:dd:d9:dd:c25:c25:94de:435
282c19:dd:d9:dd:c25:c25:94de:436/1272c19:dd:d9:dd:c25:c25:94de:437
292c19:dd:d9:dd:c25:c25:94de:438/1272c19:dd:d9:dd:c25:c25:94de:439
302c19:dd:d9:dd:c25:c25:94de:43a/1272c19:dd:d9:dd:c25:c25:94de:43b
312c19:dd:d9:dd:c25:c25:94de:43c/1272c19:dd:d9:dd:c25:c25:94de:43d
322c19:dd:d9:dd:c25:c25:94de:43e/1272c19:dd:d9:dd:c25:c25:94de:43f
332c19:dd:d9:dd:c25:c25:94de:440/1272c19:dd:d9:dd:c25:c25:94de:441
342c19:dd:d9:dd:c25:c25:94de:442/1272c19:dd:d9:dd:c25:c25:94de:443
352c19:dd:d9:dd:c25:c25:94de:444/1272c19:dd:d9:dd:c25:c25:94de:445
362c19:dd:d9:dd:c25:c25:94de:446/1272c19:dd:d9:dd:c25:c25:94de:447
372c19:dd:d9:dd:c25:c25:94de:448/1272c19:dd:d9:dd:c25:c25:94de:449
382c19:dd:d9:dd:c25:c25:94de:44a/1272c19:dd:d9:dd:c25:c25:94de:44b
392c19:dd:d9:dd:c25:c25:94de:44c/1272c19:dd:d9:dd:c25:c25:94de:44d
402c19:dd:d9:dd:c25:c25:94de:44e/1272c19:dd:d9:dd:c25:c25:94de:44f
412c19:dd:d9:dd:c25:c25:94de:450/1272c19:dd:d9:dd:c25:c25:94de:451
422c19:dd:d9:dd:c25:c25:94de:452/1272c19:dd:d9:dd:c25:c25:94de:453
432c19:dd:d9:dd:c25:c25:94de:454/1272c19:dd:d9:dd:c25:c25:94de:455
442c19:dd:d9:dd:c25:c25:94de:456/1272c19:dd:d9:dd:c25:c25:94de:457
452c19:dd:d9:dd:c25:c25:94de:458/1272c19:dd:d9:dd:c25:c25:94de:459
462c19:dd:d9:dd:c25:c25:94de:45a/1272c19:dd:d9:dd:c25:c25:94de:45b
472c19:dd:d9:dd:c25:c25:94de:45c/1272c19:dd:d9:dd:c25:c25:94de:45d
482c19:dd:d9:dd:c25:c25:94de:45e/1272c19:dd:d9:dd:c25:c25:94de:45f
492c19:dd:d9:dd:c25:c25:94de:460/1272c19:dd:d9:dd:c25:c25:94de:461
502c19:dd:d9:dd:c25:c25:94de:462/1272c19:dd:d9:dd:c25:c25:94de:463
512c19:dd:d9:dd:c25:c25:94de:464/1272c19:dd:d9:dd:c25:c25:94de:465
522c19:dd:d9:dd:c25:c25:94de:466/1272c19:dd:d9:dd:c25:c25:94de:467
532c19:dd:d9:dd:c25:c25:94de:468/1272c19:dd:d9:dd:c25:c25:94de:469
542c19:dd:d9:dd:c25:c25:94de:46a/1272c19:dd:d9:dd:c25:c25:94de:46b
552c19:dd:d9:dd:c25:c25:94de:46c/1272c19:dd:d9:dd:c25:c25:94de:46d
562c19:dd:d9:dd:c25:c25:94de:46e/1272c19:dd:d9:dd:c25:c25:94de:46f
572c19:dd:d9:dd:c25:c25:94de:470/1272c19:dd:d9:dd:c25:c25:94de:471
582c19:dd:d9:dd:c25:c25:94de:472/1272c19:dd:d9:dd:c25:c25:94de:473
592c19:dd:d9:dd:c25:c25:94de:474/1272c19:dd:d9:dd:c25:c25:94de:475
602c19:dd:d9:dd:c25:c25:94de:476/1272c19:dd:d9:dd:c25:c25:94de:477
612c19:dd:d9:dd:c25:c25:94de:478/1272c19:dd:d9:dd:c25:c25:94de:479
622c19:dd:d9:dd:c25:c25:94de:47a/1272c19:dd:d9:dd:c25:c25:94de:47b
632c19:dd:d9:dd:c25:c25:94de:47c/1272c19:dd:d9:dd:c25:c25:94de:47d
642c19:dd:d9:dd:c25:c25:94de:47e/1272c19:dd:d9:dd:c25:c25:94de:47f
652c19:dd:d9:dd:c25:c25:94de:480/1272c19:dd:d9:dd:c25:c25:94de:481
662c19:dd:d9:dd:c25:c25:94de:482/1272c19:dd:d9:dd:c25:c25:94de:483
672c19:dd:d9:dd:c25:c25:94de:484/1272c19:dd:d9:dd:c25:c25:94de:485
682c19:dd:d9:dd:c25:c25:94de:486/1272c19:dd:d9:dd:c25:c25:94de:487
692c19:dd:d9:dd:c25:c25:94de:488/1272c19:dd:d9:dd:c25:c25:94de:489
702c19:dd:d9:dd:c25:c25:94de:48a/1272c19:dd:d9:dd:c25:c25:94de:48b
712c19:dd:d9:dd:c25:c25:94de:48c/1272c19:dd:d9:dd:c25:c25:94de:48d
722c19:dd:d9:dd:c25:c25:94de:48e/1272c19:dd:d9:dd:c25:c25:94de:48f
732c19:dd:d9:dd:c25:c25:94de:490/1272c19:dd:d9:dd:c25:c25:94de:491
742c19:dd:d9:dd:c25:c25:94de:492/1272c19:dd:d9:dd:c25:c25:94de:493
752c19:dd:d9:dd:c25:c25:94de:494/1272c19:dd:d9:dd:c25:c25:94de:495
762c19:dd:d9:dd:c25:c25:94de:496/1272c19:dd:d9:dd:c25:c25:94de:497
772c19:dd:d9:dd:c25:c25:94de:498/1272c19:dd:d9:dd:c25:c25:94de:499
782c19:dd:d9:dd:c25:c25:94de:49a/1272c19:dd:d9:dd:c25:c25:94de:49b
792c19:dd:d9:dd:c25:c25:94de:49c/1272c19:dd:d9:dd:c25:c25:94de:49d
802c19:dd:d9:dd:c25:c25:94de:49e/1272c19:dd:d9:dd:c25:c25:94de:49f
812c19:dd:d9:dd:c25:c25:94de:4a0/1272c19:dd:d9:dd:c25:c25:94de:4a1
822c19:dd:d9:dd:c25:c25:94de:4a2/1272c19:dd:d9:dd:c25:c25:94de:4a3
832c19:dd:d9:dd:c25:c25:94de:4a4/1272c19:dd:d9:dd:c25:c25:94de:4a5
842c19:dd:d9:dd:c25:c25:94de:4a6/1272c19:dd:d9:dd:c25:c25:94de:4a7
852c19:dd:d9:dd:c25:c25:94de:4a8/1272c19:dd:d9:dd:c25:c25:94de:4a9
862c19:dd:d9:dd:c25:c25:94de:4aa/1272c19:dd:d9:dd:c25:c25:94de:4ab
872c19:dd:d9:dd:c25:c25:94de:4ac/1272c19:dd:d9:dd:c25:c25:94de:4ad
882c19:dd:d9:dd:c25:c25:94de:4ae/1272c19:dd:d9:dd:c25:c25:94de:4af
892c19:dd:d9:dd:c25:c25:94de:4b0/1272c19:dd:d9:dd:c25:c25:94de:4b1
902c19:dd:d9:dd:c25:c25:94de:4b2/1272c19:dd:d9:dd:c25:c25:94de:4b3
912c19:dd:d9:dd:c25:c25:94de:4b4/1272c19:dd:d9:dd:c25:c25:94de:4b5
922c19:dd:d9:dd:c25:c25:94de:4b6/1272c19:dd:d9:dd:c25:c25:94de:4b7
932c19:dd:d9:dd:c25:c25:94de:4b8/1272c19:dd:d9:dd:c25:c25:94de:4b9
942c19:dd:d9:dd:c25:c25:94de:4ba/1272c19:dd:d9:dd:c25:c25:94de:4bb
952c19:dd:d9:dd:c25:c25:94de:4bc/1272c19:dd:d9:dd:c25:c25:94de:4bd
962c19:dd:d9:dd:c25:c25:94de:4be/1272c19:dd:d9:dd:c25:c25:94de:4bf
972c19:dd:d9:dd:c25:c25:94de:4c0/1272c19:dd:d9:dd:c25:c25:94de:4c1
982c19:dd:d9:dd:c25:c25:94de:4c2/1272c19:dd:d9:dd:c25:c25:94de:4c3
992c19:dd:d9:dd:c25:c25:94de:4c4/1272c19:dd:d9:dd:c25:c25:94de:4c5
1002c19:dd:d9:dd:c25:c25:94de:4c6/1272c19:dd:d9:dd:c25:c25:94de:4c7
1012c19:dd:d9:dd:c25:c25:94de:4c8/1272c19:dd:d9:dd:c25:c25:94de:4c9
1022c19:dd:d9:dd:c25:c25:94de:4ca/1272c19:dd:d9:dd:c25:c25:94de:4cb
1032c19:dd:d9:dd:c25:c25:94de:4cc/1272c19:dd:d9:dd:c25:c25:94de:4cd
1042c19:dd:d9:dd:c25:c25:94de:4ce/1272c19:dd:d9:dd:c25:c25:94de:4cf
1052c19:dd:d9:dd:c25:c25:94de:4d0/1272c19:dd:d9:dd:c25:c25:94de:4d1
1062c19:dd:d9:dd:c25:c25:94de:4d2/1272c19:dd:d9:dd:c25:c25:94de:4d3
1072c19:dd:d9:dd:c25:c25:94de:4d4/1272c19:dd:d9:dd:c25:c25:94de:4d5
1082c19:dd:d9:dd:c25:c25:94de:4d6/1272c19:dd:d9:dd:c25:c25:94de:4d7
1092c19:dd:d9:dd:c25:c25:94de:4d8/1272c19:dd:d9:dd:c25:c25:94de:4d9
1102c19:dd:d9:dd:c25:c25:94de:4da/1272c19:dd:d9:dd:c25:c25:94de:4db
1112c19:dd:d9:dd:c25:c25:94de:4dc/1272c19:dd:d9:dd:c25:c25:94de:4dd
1122c19:dd:d9:dd:c25:c25:94de:4de/1272c19:dd:d9:dd:c25:c25:94de:4df
1132c19:dd:d9:dd:c25:c25:94de:4e0/1272c19:dd:d9:dd:c25:c25:94de:4e1
1142c19:dd:d9:dd:c25:c25:94de:4e2/1272c19:dd:d9:dd:c25:c25:94de:4e3
1152c19:dd:d9:dd:c25:c25:94de:4e4/1272c19:dd:d9:dd:c25:c25:94de:4e5
1162c19:dd:d9:dd:c25:c25:94de:4e6/1272c19:dd:d9:dd:c25:c25:94de:4e7
1172c19:dd:d9:dd:c25:c25:94de:4e8/1272c19:dd:d9:dd:c25:c25:94de:4e9
1182c19:dd:d9:dd:c25:c25:94de:4ea/1272c19:dd:d9:dd:c25:c25:94de:4eb
1192c19:dd:d9:dd:c25:c25:94de:4ec/1272c19:dd:d9:dd:c25:c25:94de:4ed
1202c19:dd:d9:dd:c25:c25:94de:4ee/1272c19:dd:d9:dd:c25:c25:94de:4ef
1212c19:dd:d9:dd:c25:c25:94de:4f0/1272c19:dd:d9:dd:c25:c25:94de:4f1
1222c19:dd:d9:dd:c25:c25:94de:4f2/1272c19:dd:d9:dd:c25:c25:94de:4f3
1232c19:dd:d9:dd:c25:c25:94de:4f4/1272c19:dd:d9:dd:c25:c25:94de:4f5
1242c19:dd:d9:dd:c25:c25:94de:4f6/1272c19:dd:d9:dd:c25:c25:94de:4f7
1252c19:dd:d9:dd:c25:c25:94de:4f8/1272c19:dd:d9:dd:c25:c25:94de:4f9
1262c19:dd:d9:dd:c25:c25:94de:4fa/1272c19:dd:d9:dd:c25:c25:94de:4fb
1272c19:dd:d9:dd:c25:c25:94de:4fc/1272c19:dd:d9:dd:c25:c25:94de:4fd
1282c19:dd:d9:dd:c25:c25:94de:4fe/1272c19:dd:d9:dd:c25:c25:94de:4ff
1292c19:dd:d9:dd:c25:c25:94de:500/1272c19:dd:d9:dd:c25:c25:94de:501
1302c19:dd:d9:dd:c25:c25:94de:502/1272c19:dd:d9:dd:c25:c25:94de:503
1312c19:dd:d9:dd:c25:c25:94de:504/1272c19:dd:d9:dd:c25:c25:94de:505
1322c19:dd:d9:dd:c25:c25:94de:506/1272c19:dd:d9:dd:c25:c25:94de:507
1332c19:dd:d9:dd:c25:c25:94de:508/1272c19:dd:d9:dd:c25:c25:94de:509
1342c19:dd:d9:dd:c25:c25:94de:50a/1272c19:dd:d9:dd:c25:c25:94de:50b
1352c19:dd:d9:dd:c25:c25:94de:50c/1272c19:dd:d9:dd:c25:c25:94de:50d
1362c19:dd:d9:dd:c25:c25:94de:50e/1272c19:dd:d9:dd:c25:c25:94de:50f
1372c19:dd:d9:dd:c25:c25:94de:510/1272c19:dd:d9:dd:c25:c25:94de:511
1382c19:dd:d9:dd:c25:c25:94de:512/1272c19:dd:d9:dd:c25:c25:94de:513
1392c19:dd:d9:dd:c25:c25:94de:514/1272c19:dd:d9:dd:c25:c25:94de:515
1402c19:dd:d9:dd:c25:c25:94de:516/1272c19:dd:d9:dd:c25:c25:94de:517
1412c19:dd:d9:dd:c25:c25:94de:518/1272c19:dd:d9:dd:c25:c25:94de:519
1422c19:dd:d9:dd:c25:c25:94de:51a/1272c19:dd:d9:dd:c25:c25:94de:51b
1432c19:dd:d9:dd:c25:c25:94de:51c/1272c19:dd:d9:dd:c25:c25:94de:51d
1442c19:dd:d9:dd:c25:c25:94de:51e/1272c19:dd:d9:dd:c25:c25:94de:51f
1452c19:dd:d9:dd:c25:c25:94de:520/1272c19:dd:d9:dd:c25:c25:94de:521
1462c19:dd:d9:dd:c25:c25:94de:522/1272c19:dd:d9:dd:c25:c25:94de:523
1472c19:dd:d9:dd:c25:c25:94de:524/1272c19:dd:d9:dd:c25:c25:94de:525
1482c19:dd:d9:dd:c25:c25:94de:526/1272c19:dd:d9:dd:c25:c25:94de:527
1492c19:dd:d9:dd:c25:c25:94de:528/1272c19:dd:d9:dd:c25:c25:94de:529
1502c19:dd:d9:dd:c25:c25:94de:52a/1272c19:dd:d9:dd:c25:c25:94de:52b
1512c19:dd:d9:dd:c25:c25:94de:52c/1272c19:dd:d9:dd:c25:c25:94de:52d
1522c19:dd:d9:dd:c25:c25:94de:52e/1272c19:dd:d9:dd:c25:c25:94de:52f
1532c19:dd:d9:dd:c25:c25:94de:530/1272c19:dd:d9:dd:c25:c25:94de:531
1542c19:dd:d9:dd:c25:c25:94de:532/1272c19:dd:d9:dd:c25:c25:94de:533
1552c19:dd:d9:dd:c25:c25:94de:534/1272c19:dd:d9:dd:c25:c25:94de:535
1562c19:dd:d9:dd:c25:c25:94de:536/1272c19:dd:d9:dd:c25:c25:94de:537
1572c19:dd:d9:dd:c25:c25:94de:538/1272c19:dd:d9:dd:c25:c25:94de:539
1582c19:dd:d9:dd:c25:c25:94de:53a/1272c19:dd:d9:dd:c25:c25:94de:53b
1592c19:dd:d9:dd:c25:c25:94de:53c/1272c19:dd:d9:dd:c25:c25:94de:53d
1602c19:dd:d9:dd:c25:c25:94de:53e/1272c19:dd:d9:dd:c25:c25:94de:53f
1612c19:dd:d9:dd:c25:c25:94de:540/1272c19:dd:d9:dd:c25:c25:94de:541
1622c19:dd:d9:dd:c25:c25:94de:542/1272c19:dd:d9:dd:c25:c25:94de:543
1632c19:dd:d9:dd:c25:c25:94de:544/1272c19:dd:d9:dd:c25:c25:94de:545
1642c19:dd:d9:dd:c25:c25:94de:546/1272c19:dd:d9:dd:c25:c25:94de:547
1652c19:dd:d9:dd:c25:c25:94de:548/1272c19:dd:d9:dd:c25:c25:94de:549
1662c19:dd:d9:dd:c25:c25:94de:54a/1272c19:dd:d9:dd:c25:c25:94de:54b
1672c19:dd:d9:dd:c25:c25:94de:54c/1272c19:dd:d9:dd:c25:c25:94de:54d
1682c19:dd:d9:dd:c25:c25:94de:54e/1272c19:dd:d9:dd:c25:c25:94de:54f
1692c19:dd:d9:dd:c25:c25:94de:550/1272c19:dd:d9:dd:c25:c25:94de:551
1702c19:dd:d9:dd:c25:c25:94de:552/1272c19:dd:d9:dd:c25:c25:94de:553
1712c19:dd:d9:dd:c25:c25:94de:554/1272c19:dd:d9:dd:c25:c25:94de:555
1722c19:dd:d9:dd:c25:c25:94de:556/1272c19:dd:d9:dd:c25:c25:94de:557
1732c19:dd:d9:dd:c25:c25:94de:558/1272c19:dd:d9:dd:c25:c25:94de:559
1742c19:dd:d9:dd:c25:c25:94de:55a/1272c19:dd:d9:dd:c25:c25:94de:55b
1752c19:dd:d9:dd:c25:c25:94de:55c/1272c19:dd:d9:dd:c25:c25:94de:55d
1762c19:dd:d9:dd:c25:c25:94de:55e/1272c19:dd:d9:dd:c25:c25:94de:55f
1772c19:dd:d9:dd:c25:c25:94de:560/1272c19:dd:d9:dd:c25:c25:94de:561
1782c19:dd:d9:dd:c25:c25:94de:562/1272c19:dd:d9:dd:c25:c25:94de:563
1792c19:dd:d9:dd:c25:c25:94de:564/1272c19:dd:d9:dd:c25:c25:94de:565
1802c19:dd:d9:dd:c25:c25:94de:566/1272c19:dd:d9:dd:c25:c25:94de:567
1812c19:dd:d9:dd:c25:c25:94de:568/1272c19:dd:d9:dd:c25:c25:94de:569
1822c19:dd:d9:dd:c25:c25:94de:56a/1272c19:dd:d9:dd:c25:c25:94de:56b
1832c19:dd:d9:dd:c25:c25:94de:56c/1272c19:dd:d9:dd:c25:c25:94de:56d
1842c19:dd:d9:dd:c25:c25:94de:56e/1272c19:dd:d9:dd:c25:c25:94de:56f
1852c19:dd:d9:dd:c25:c25:94de:570/1272c19:dd:d9:dd:c25:c25:94de:571
1862c19:dd:d9:dd:c25:c25:94de:572/1272c19:dd:d9:dd:c25:c25:94de:573
1872c19:dd:d9:dd:c25:c25:94de:574/1272c19:dd:d9:dd:c25:c25:94de:575
1882c19:dd:d9:dd:c25:c25:94de:576/1272c19:dd:d9:dd:c25:c25:94de:577
1892c19:dd:d9:dd:c25:c25:94de:578/1272c19:dd:d9:dd:c25:c25:94de:579
1902c19:dd:d9:dd:c25:c25:94de:57a/1272c19:dd:d9:dd:c25:c25:94de:57b
1912c19:dd:d9:dd:c25:c25:94de:57c/1272c19:dd:d9:dd:c25:c25:94de:57d
1922c19:dd:d9:dd:c25:c25:94de:57e/1272c19:dd:d9:dd:c25:c25:94de:57f
1932c19:dd:d9:dd:c25:c25:94de:580/1272c19:dd:d9:dd:c25:c25:94de:581
1942c19:dd:d9:dd:c25:c25:94de:582/1272c19:dd:d9:dd:c25:c25:94de:583
1952c19:dd:d9:dd:c25:c25:94de:584/1272c19:dd:d9:dd:c25:c25:94de:585
1962c19:dd:d9:dd:c25:c25:94de:586/1272c19:dd:d9:dd:c25:c25:94de:587
1972c19:dd:d9:dd:c25:c25:94de:588/1272c19:dd:d9:dd:c25:c25:94de:589
1982c19:dd:d9:dd:c25:c25:94de:58a/1272c19:dd:d9:dd:c25:c25:94de:58b
1992c19:dd:d9:dd:c25:c25:94de:58c/1272c19:dd:d9:dd:c25:c25:94de:58d
2002c19:dd:d9:dd:c25:c25:94de:58e/1272c19:dd:d9:dd:c25:c25:94de:58f
2012c19:dd:d9:dd:c25:c25:94de:590/1272c19:dd:d9:dd:c25:c25:94de:591
2022c19:dd:d9:dd:c25:c25:94de:592/1272c19:dd:d9:dd:c25:c25:94de:593
2032c19:dd:d9:dd:c25:c25:94de:594/1272c19:dd:d9:dd:c25:c25:94de:595
2042c19:dd:d9:dd:c25:c25:94de:596/1272c19:dd:d9:dd:c25:c25:94de:597
2052c19:dd:d9:dd:c25:c25:94de:598/1272c19:dd:d9:dd:c25:c25:94de:599
2062c19:dd:d9:dd:c25:c25:94de:59a/1272c19:dd:d9:dd:c25:c25:94de:59b
2072c19:dd:d9:dd:c25:c25:94de:59c/1272c19:dd:d9:dd:c25:c25:94de:59d
2082c19:dd:d9:dd:c25:c25:94de:59e/1272c19:dd:d9:dd:c25:c25:94de:59f
2092c19:dd:d9:dd:c25:c25:94de:5a0/1272c19:dd:d9:dd:c25:c25:94de:5a1
2102c19:dd:d9:dd:c25:c25:94de:5a2/1272c19:dd:d9:dd:c25:c25:94de:5a3
2112c19:dd:d9:dd:c25:c25:94de:5a4/1272c19:dd:d9:dd:c25:c25:94de:5a5
2122c19:dd:d9:dd:c25:c25:94de:5a6/1272c19:dd:d9:dd:c25:c25:94de:5a7
2132c19:dd:d9:dd:c25:c25:94de:5a8/1272c19:dd:d9:dd:c25:c25:94de:5a9
2142c19:dd:d9:dd:c25:c25:94de:5aa/1272c19:dd:d9:dd:c25:c25:94de:5ab
2152c19:dd:d9:dd:c25:c25:94de:5ac/1272c19:dd:d9:dd:c25:c25:94de:5ad
2162c19:dd:d9:dd:c25:c25:94de:5ae/1272c19:dd:d9:dd:c25:c25:94de:5af
2172c19:dd:d9:dd:c25:c25:94de:5b0/1272c19:dd:d9:dd:c25:c25:94de:5b1
2182c19:dd:d9:dd:c25:c25:94de:5b2/1272c19:dd:d9:dd:c25:c25:94de:5b3
2192c19:dd:d9:dd:c25:c25:94de:5b4/1272c19:dd:d9:dd:c25:c25:94de:5b5
2202c19:dd:d9:dd:c25:c25:94de:5b6/1272c19:dd:d9:dd:c25:c25:94de:5b7
2212c19:dd:d9:dd:c25:c25:94de:5b8/1272c19:dd:d9:dd:c25:c25:94de:5b9
2222c19:dd:d9:dd:c25:c25:94de:5ba/1272c19:dd:d9:dd:c25:c25:94de:5bb
2232c19:dd:d9:dd:c25:c25:94de:5bc/1272c19:dd:d9:dd:c25:c25:94de:5bd
2242c19:dd:d9:dd:c25:c25:94de:5be/1272c19:dd:d9:dd:c25:c25:94de:5bf
2252c19:dd:d9:dd:c25:c25:94de:5c0/1272c19:dd:d9:dd:c25:c25:94de:5c1
2262c19:dd:d9:dd:c25:c25:94de:5c2/1272c19:dd:d9:dd:c25:c25:94de:5c3
2272c19:dd:d9:dd:c25:c25:94de:5c4/1272c19:dd:d9:dd:c25:c25:94de:5c5
2282c19:dd:d9:dd:c25:c25:94de:5c6/1272c19:dd:d9:dd:c25:c25:94de:5c7
2292c19:dd:d9:dd:c25:c25:94de:5c8/1272c19:dd:d9:dd:c25:c25:94de:5c9
2302c19:dd:d9:dd:c25:c25:94de:5ca/1272c19:dd:d9:dd:c25:c25:94de:5cb
2312c19:dd:d9:dd:c25:c25:94de:5cc/1272c19:dd:d9:dd:c25:c25:94de:5cd
2322c19:dd:d9:dd:c25:c25:94de:5ce/1272c19:dd:d9:dd:c25:c25:94de:5cf
2332c19:dd:d9:dd:c25:c25:94de:5d0/1272c19:dd:d9:dd:c25:c25:94de:5d1
2342c19:dd:d9:dd:c25:c25:94de:5d2/1272c19:dd:d9:dd:c25:c25:94de:5d3
2352c19:dd:d9:dd:c25:c25:94de:5d4/1272c19:dd:d9:dd:c25:c25:94de:5d5
2362c19:dd:d9:dd:c25:c25:94de:5d6/1272c19:dd:d9:dd:c25:c25:94de:5d7
2372c19:dd:d9:dd:c25:c25:94de:5d8/1272c19:dd:d9:dd:c25:c25:94de:5d9
2382c19:dd:d9:dd:c25:c25:94de:5da/1272c19:dd:d9:dd:c25:c25:94de:5db
2392c19:dd:d9:dd:c25:c25:94de:5dc/1272c19:dd:d9:dd:c25:c25:94de:5dd
2402c19:dd:d9:dd:c25:c25:94de:5de/1272c19:dd:d9:dd:c25:c25:94de:5df
2412c19:dd:d9:dd:c25:c25:94de:5e0/1272c19:dd:d9:dd:c25:c25:94de:5e1
2422c19:dd:d9:dd:c25:c25:94de:5e2/1272c19:dd:d9:dd:c25:c25:94de:5e3
2432c19:dd:d9:dd:c25:c25:94de:5e4/1272c19:dd:d9:dd:c25:c25:94de:5e5
2442c19:dd:d9:dd:c25:c25:94de:5e6/1272c19:dd:d9:dd:c25:c25:94de:5e7
2452c19:dd:d9:dd:c25:c25:94de:5e8/1272c19:dd:d9:dd:c25:c25:94de:5e9
2462c19:dd:d9:dd:c25:c25:94de:5ea/1272c19:dd:d9:dd:c25:c25:94de:5eb
2472c19:dd:d9:dd:c25:c25:94de:5ec/1272c19:dd:d9:dd:c25:c25:94de:5ed
2482c19:dd:d9:dd:c25:c25:94de:5ee/1272c19:dd:d9:dd:c25:c25:94de:5ef
2492c19:dd:d9:dd:c25:c25:94de:5f0/1272c19:dd:d9:dd:c25:c25:94de:5f1
2502c19:dd:d9:dd:c25:c25:94de:5f2/1272c19:dd:d9:dd:c25:c25:94de:5f3
2512c19:dd:d9:dd:c25:c25:94de:5f4/1272c19:dd:d9:dd:c25:c25:94de:5f5
2522c19:dd:d9:dd:c25:c25:94de:5f6/1272c19:dd:d9:dd:c25:c25:94de:5f7
2532c19:dd:d9:dd:c25:c25:94de:5f8/1272c19:dd:d9:dd:c25:c25:94de:5f9
2542c19:dd:d9:dd:c25:c25:94de:5fa/1272c19:dd:d9:dd:c25:c25:94de:5fb
2552c19:dd:d9:dd:c25:c25:94de:5fc/1272c19:dd:d9:dd:c25:c25:94de:5fd
2562c19:dd:d9:dd:c25:c25:94de:5fe/1272c19:dd:d9:dd:c25:c25:94de:5ff

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.