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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/118
Addresses1,024
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:f400/118
First address
2c19:dd:d9:dd:c25:c25:94de:f400
Last address
2c19:dd:d9:dd:c25:c25:94de:f7ff
Addresses
1,024
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:f400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
4.f.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.f.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
6.f.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
7.f.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
/118 is not on a 4-bit boundary, so it takes 4 /120 zones.
Split into smaller subnets/127
/119 (2)/120 (4)/121 (8)/122 (16)/124 (64)/127 (512)/128 (1,024)

2c19:dd:d9:dd:c25:c25:94de:f400/118 makes 512 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:f400/1272c19:dd:d9:dd:c25:c25:94de:f401
22c19:dd:d9:dd:c25:c25:94de:f402/1272c19:dd:d9:dd:c25:c25:94de:f403
32c19:dd:d9:dd:c25:c25:94de:f404/1272c19:dd:d9:dd:c25:c25:94de:f405
42c19:dd:d9:dd:c25:c25:94de:f406/1272c19:dd:d9:dd:c25:c25:94de:f407
52c19:dd:d9:dd:c25:c25:94de:f408/1272c19:dd:d9:dd:c25:c25:94de:f409
62c19:dd:d9:dd:c25:c25:94de:f40a/1272c19:dd:d9:dd:c25:c25:94de:f40b
72c19:dd:d9:dd:c25:c25:94de:f40c/1272c19:dd:d9:dd:c25:c25:94de:f40d
82c19:dd:d9:dd:c25:c25:94de:f40e/1272c19:dd:d9:dd:c25:c25:94de:f40f
92c19:dd:d9:dd:c25:c25:94de:f410/1272c19:dd:d9:dd:c25:c25:94de:f411
102c19:dd:d9:dd:c25:c25:94de:f412/1272c19:dd:d9:dd:c25:c25:94de:f413
112c19:dd:d9:dd:c25:c25:94de:f414/1272c19:dd:d9:dd:c25:c25:94de:f415
122c19:dd:d9:dd:c25:c25:94de:f416/1272c19:dd:d9:dd:c25:c25:94de:f417
132c19:dd:d9:dd:c25:c25:94de:f418/1272c19:dd:d9:dd:c25:c25:94de:f419
142c19:dd:d9:dd:c25:c25:94de:f41a/1272c19:dd:d9:dd:c25:c25:94de:f41b
152c19:dd:d9:dd:c25:c25:94de:f41c/1272c19:dd:d9:dd:c25:c25:94de:f41d
162c19:dd:d9:dd:c25:c25:94de:f41e/1272c19:dd:d9:dd:c25:c25:94de:f41f
172c19:dd:d9:dd:c25:c25:94de:f420/1272c19:dd:d9:dd:c25:c25:94de:f421
182c19:dd:d9:dd:c25:c25:94de:f422/1272c19:dd:d9:dd:c25:c25:94de:f423
192c19:dd:d9:dd:c25:c25:94de:f424/1272c19:dd:d9:dd:c25:c25:94de:f425
202c19:dd:d9:dd:c25:c25:94de:f426/1272c19:dd:d9:dd:c25:c25:94de:f427
212c19:dd:d9:dd:c25:c25:94de:f428/1272c19:dd:d9:dd:c25:c25:94de:f429
222c19:dd:d9:dd:c25:c25:94de:f42a/1272c19:dd:d9:dd:c25:c25:94de:f42b
232c19:dd:d9:dd:c25:c25:94de:f42c/1272c19:dd:d9:dd:c25:c25:94de:f42d
242c19:dd:d9:dd:c25:c25:94de:f42e/1272c19:dd:d9:dd:c25:c25:94de:f42f
252c19:dd:d9:dd:c25:c25:94de:f430/1272c19:dd:d9:dd:c25:c25:94de:f431
262c19:dd:d9:dd:c25:c25:94de:f432/1272c19:dd:d9:dd:c25:c25:94de:f433
272c19:dd:d9:dd:c25:c25:94de:f434/1272c19:dd:d9:dd:c25:c25:94de:f435
282c19:dd:d9:dd:c25:c25:94de:f436/1272c19:dd:d9:dd:c25:c25:94de:f437
292c19:dd:d9:dd:c25:c25:94de:f438/1272c19:dd:d9:dd:c25:c25:94de:f439
302c19:dd:d9:dd:c25:c25:94de:f43a/1272c19:dd:d9:dd:c25:c25:94de:f43b
312c19:dd:d9:dd:c25:c25:94de:f43c/1272c19:dd:d9:dd:c25:c25:94de:f43d
322c19:dd:d9:dd:c25:c25:94de:f43e/1272c19:dd:d9:dd:c25:c25:94de:f43f
332c19:dd:d9:dd:c25:c25:94de:f440/1272c19:dd:d9:dd:c25:c25:94de:f441
342c19:dd:d9:dd:c25:c25:94de:f442/1272c19:dd:d9:dd:c25:c25:94de:f443
352c19:dd:d9:dd:c25:c25:94de:f444/1272c19:dd:d9:dd:c25:c25:94de:f445
362c19:dd:d9:dd:c25:c25:94de:f446/1272c19:dd:d9:dd:c25:c25:94de:f447
372c19:dd:d9:dd:c25:c25:94de:f448/1272c19:dd:d9:dd:c25:c25:94de:f449
382c19:dd:d9:dd:c25:c25:94de:f44a/1272c19:dd:d9:dd:c25:c25:94de:f44b
392c19:dd:d9:dd:c25:c25:94de:f44c/1272c19:dd:d9:dd:c25:c25:94de:f44d
402c19:dd:d9:dd:c25:c25:94de:f44e/1272c19:dd:d9:dd:c25:c25:94de:f44f
412c19:dd:d9:dd:c25:c25:94de:f450/1272c19:dd:d9:dd:c25:c25:94de:f451
422c19:dd:d9:dd:c25:c25:94de:f452/1272c19:dd:d9:dd:c25:c25:94de:f453
432c19:dd:d9:dd:c25:c25:94de:f454/1272c19:dd:d9:dd:c25:c25:94de:f455
442c19:dd:d9:dd:c25:c25:94de:f456/1272c19:dd:d9:dd:c25:c25:94de:f457
452c19:dd:d9:dd:c25:c25:94de:f458/1272c19:dd:d9:dd:c25:c25:94de:f459
462c19:dd:d9:dd:c25:c25:94de:f45a/1272c19:dd:d9:dd:c25:c25:94de:f45b
472c19:dd:d9:dd:c25:c25:94de:f45c/1272c19:dd:d9:dd:c25:c25:94de:f45d
482c19:dd:d9:dd:c25:c25:94de:f45e/1272c19:dd:d9:dd:c25:c25:94de:f45f
492c19:dd:d9:dd:c25:c25:94de:f460/1272c19:dd:d9:dd:c25:c25:94de:f461
502c19:dd:d9:dd:c25:c25:94de:f462/1272c19:dd:d9:dd:c25:c25:94de:f463
512c19:dd:d9:dd:c25:c25:94de:f464/1272c19:dd:d9:dd:c25:c25:94de:f465
522c19:dd:d9:dd:c25:c25:94de:f466/1272c19:dd:d9:dd:c25:c25:94de:f467
532c19:dd:d9:dd:c25:c25:94de:f468/1272c19:dd:d9:dd:c25:c25:94de:f469
542c19:dd:d9:dd:c25:c25:94de:f46a/1272c19:dd:d9:dd:c25:c25:94de:f46b
552c19:dd:d9:dd:c25:c25:94de:f46c/1272c19:dd:d9:dd:c25:c25:94de:f46d
562c19:dd:d9:dd:c25:c25:94de:f46e/1272c19:dd:d9:dd:c25:c25:94de:f46f
572c19:dd:d9:dd:c25:c25:94de:f470/1272c19:dd:d9:dd:c25:c25:94de:f471
582c19:dd:d9:dd:c25:c25:94de:f472/1272c19:dd:d9:dd:c25:c25:94de:f473
592c19:dd:d9:dd:c25:c25:94de:f474/1272c19:dd:d9:dd:c25:c25:94de:f475
602c19:dd:d9:dd:c25:c25:94de:f476/1272c19:dd:d9:dd:c25:c25:94de:f477
612c19:dd:d9:dd:c25:c25:94de:f478/1272c19:dd:d9:dd:c25:c25:94de:f479
622c19:dd:d9:dd:c25:c25:94de:f47a/1272c19:dd:d9:dd:c25:c25:94de:f47b
632c19:dd:d9:dd:c25:c25:94de:f47c/1272c19:dd:d9:dd:c25:c25:94de:f47d
642c19:dd:d9:dd:c25:c25:94de:f47e/1272c19:dd:d9:dd:c25:c25:94de:f47f
652c19:dd:d9:dd:c25:c25:94de:f480/1272c19:dd:d9:dd:c25:c25:94de:f481
662c19:dd:d9:dd:c25:c25:94de:f482/1272c19:dd:d9:dd:c25:c25:94de:f483
672c19:dd:d9:dd:c25:c25:94de:f484/1272c19:dd:d9:dd:c25:c25:94de:f485
682c19:dd:d9:dd:c25:c25:94de:f486/1272c19:dd:d9:dd:c25:c25:94de:f487
692c19:dd:d9:dd:c25:c25:94de:f488/1272c19:dd:d9:dd:c25:c25:94de:f489
702c19:dd:d9:dd:c25:c25:94de:f48a/1272c19:dd:d9:dd:c25:c25:94de:f48b
712c19:dd:d9:dd:c25:c25:94de:f48c/1272c19:dd:d9:dd:c25:c25:94de:f48d
722c19:dd:d9:dd:c25:c25:94de:f48e/1272c19:dd:d9:dd:c25:c25:94de:f48f
732c19:dd:d9:dd:c25:c25:94de:f490/1272c19:dd:d9:dd:c25:c25:94de:f491
742c19:dd:d9:dd:c25:c25:94de:f492/1272c19:dd:d9:dd:c25:c25:94de:f493
752c19:dd:d9:dd:c25:c25:94de:f494/1272c19:dd:d9:dd:c25:c25:94de:f495
762c19:dd:d9:dd:c25:c25:94de:f496/1272c19:dd:d9:dd:c25:c25:94de:f497
772c19:dd:d9:dd:c25:c25:94de:f498/1272c19:dd:d9:dd:c25:c25:94de:f499
782c19:dd:d9:dd:c25:c25:94de:f49a/1272c19:dd:d9:dd:c25:c25:94de:f49b
792c19:dd:d9:dd:c25:c25:94de:f49c/1272c19:dd:d9:dd:c25:c25:94de:f49d
802c19:dd:d9:dd:c25:c25:94de:f49e/1272c19:dd:d9:dd:c25:c25:94de:f49f
812c19:dd:d9:dd:c25:c25:94de:f4a0/1272c19:dd:d9:dd:c25:c25:94de:f4a1
822c19:dd:d9:dd:c25:c25:94de:f4a2/1272c19:dd:d9:dd:c25:c25:94de:f4a3
832c19:dd:d9:dd:c25:c25:94de:f4a4/1272c19:dd:d9:dd:c25:c25:94de:f4a5
842c19:dd:d9:dd:c25:c25:94de:f4a6/1272c19:dd:d9:dd:c25:c25:94de:f4a7
852c19:dd:d9:dd:c25:c25:94de:f4a8/1272c19:dd:d9:dd:c25:c25:94de:f4a9
862c19:dd:d9:dd:c25:c25:94de:f4aa/1272c19:dd:d9:dd:c25:c25:94de:f4ab
872c19:dd:d9:dd:c25:c25:94de:f4ac/1272c19:dd:d9:dd:c25:c25:94de:f4ad
882c19:dd:d9:dd:c25:c25:94de:f4ae/1272c19:dd:d9:dd:c25:c25:94de:f4af
892c19:dd:d9:dd:c25:c25:94de:f4b0/1272c19:dd:d9:dd:c25:c25:94de:f4b1
902c19:dd:d9:dd:c25:c25:94de:f4b2/1272c19:dd:d9:dd:c25:c25:94de:f4b3
912c19:dd:d9:dd:c25:c25:94de:f4b4/1272c19:dd:d9:dd:c25:c25:94de:f4b5
922c19:dd:d9:dd:c25:c25:94de:f4b6/1272c19:dd:d9:dd:c25:c25:94de:f4b7
932c19:dd:d9:dd:c25:c25:94de:f4b8/1272c19:dd:d9:dd:c25:c25:94de:f4b9
942c19:dd:d9:dd:c25:c25:94de:f4ba/1272c19:dd:d9:dd:c25:c25:94de:f4bb
952c19:dd:d9:dd:c25:c25:94de:f4bc/1272c19:dd:d9:dd:c25:c25:94de:f4bd
962c19:dd:d9:dd:c25:c25:94de:f4be/1272c19:dd:d9:dd:c25:c25:94de:f4bf
972c19:dd:d9:dd:c25:c25:94de:f4c0/1272c19:dd:d9:dd:c25:c25:94de:f4c1
982c19:dd:d9:dd:c25:c25:94de:f4c2/1272c19:dd:d9:dd:c25:c25:94de:f4c3
992c19:dd:d9:dd:c25:c25:94de:f4c4/1272c19:dd:d9:dd:c25:c25:94de:f4c5
1002c19:dd:d9:dd:c25:c25:94de:f4c6/1272c19:dd:d9:dd:c25:c25:94de:f4c7
1012c19:dd:d9:dd:c25:c25:94de:f4c8/1272c19:dd:d9:dd:c25:c25:94de:f4c9
1022c19:dd:d9:dd:c25:c25:94de:f4ca/1272c19:dd:d9:dd:c25:c25:94de:f4cb
1032c19:dd:d9:dd:c25:c25:94de:f4cc/1272c19:dd:d9:dd:c25:c25:94de:f4cd
1042c19:dd:d9:dd:c25:c25:94de:f4ce/1272c19:dd:d9:dd:c25:c25:94de:f4cf
1052c19:dd:d9:dd:c25:c25:94de:f4d0/1272c19:dd:d9:dd:c25:c25:94de:f4d1
1062c19:dd:d9:dd:c25:c25:94de:f4d2/1272c19:dd:d9:dd:c25:c25:94de:f4d3
1072c19:dd:d9:dd:c25:c25:94de:f4d4/1272c19:dd:d9:dd:c25:c25:94de:f4d5
1082c19:dd:d9:dd:c25:c25:94de:f4d6/1272c19:dd:d9:dd:c25:c25:94de:f4d7
1092c19:dd:d9:dd:c25:c25:94de:f4d8/1272c19:dd:d9:dd:c25:c25:94de:f4d9
1102c19:dd:d9:dd:c25:c25:94de:f4da/1272c19:dd:d9:dd:c25:c25:94de:f4db
1112c19:dd:d9:dd:c25:c25:94de:f4dc/1272c19:dd:d9:dd:c25:c25:94de:f4dd
1122c19:dd:d9:dd:c25:c25:94de:f4de/1272c19:dd:d9:dd:c25:c25:94de:f4df
1132c19:dd:d9:dd:c25:c25:94de:f4e0/1272c19:dd:d9:dd:c25:c25:94de:f4e1
1142c19:dd:d9:dd:c25:c25:94de:f4e2/1272c19:dd:d9:dd:c25:c25:94de:f4e3
1152c19:dd:d9:dd:c25:c25:94de:f4e4/1272c19:dd:d9:dd:c25:c25:94de:f4e5
1162c19:dd:d9:dd:c25:c25:94de:f4e6/1272c19:dd:d9:dd:c25:c25:94de:f4e7
1172c19:dd:d9:dd:c25:c25:94de:f4e8/1272c19:dd:d9:dd:c25:c25:94de:f4e9
1182c19:dd:d9:dd:c25:c25:94de:f4ea/1272c19:dd:d9:dd:c25:c25:94de:f4eb
1192c19:dd:d9:dd:c25:c25:94de:f4ec/1272c19:dd:d9:dd:c25:c25:94de:f4ed
1202c19:dd:d9:dd:c25:c25:94de:f4ee/1272c19:dd:d9:dd:c25:c25:94de:f4ef
1212c19:dd:d9:dd:c25:c25:94de:f4f0/1272c19:dd:d9:dd:c25:c25:94de:f4f1
1222c19:dd:d9:dd:c25:c25:94de:f4f2/1272c19:dd:d9:dd:c25:c25:94de:f4f3
1232c19:dd:d9:dd:c25:c25:94de:f4f4/1272c19:dd:d9:dd:c25:c25:94de:f4f5
1242c19:dd:d9:dd:c25:c25:94de:f4f6/1272c19:dd:d9:dd:c25:c25:94de:f4f7
1252c19:dd:d9:dd:c25:c25:94de:f4f8/1272c19:dd:d9:dd:c25:c25:94de:f4f9
1262c19:dd:d9:dd:c25:c25:94de:f4fa/1272c19:dd:d9:dd:c25:c25:94de:f4fb
1272c19:dd:d9:dd:c25:c25:94de:f4fc/1272c19:dd:d9:dd:c25:c25:94de:f4fd
1282c19:dd:d9:dd:c25:c25:94de:f4fe/1272c19:dd:d9:dd:c25:c25:94de:f4ff
1292c19:dd:d9:dd:c25:c25:94de:f500/1272c19:dd:d9:dd:c25:c25:94de:f501
1302c19:dd:d9:dd:c25:c25:94de:f502/1272c19:dd:d9:dd:c25:c25:94de:f503
1312c19:dd:d9:dd:c25:c25:94de:f504/1272c19:dd:d9:dd:c25:c25:94de:f505
1322c19:dd:d9:dd:c25:c25:94de:f506/1272c19:dd:d9:dd:c25:c25:94de:f507
1332c19:dd:d9:dd:c25:c25:94de:f508/1272c19:dd:d9:dd:c25:c25:94de:f509
1342c19:dd:d9:dd:c25:c25:94de:f50a/1272c19:dd:d9:dd:c25:c25:94de:f50b
1352c19:dd:d9:dd:c25:c25:94de:f50c/1272c19:dd:d9:dd:c25:c25:94de:f50d
1362c19:dd:d9:dd:c25:c25:94de:f50e/1272c19:dd:d9:dd:c25:c25:94de:f50f
1372c19:dd:d9:dd:c25:c25:94de:f510/1272c19:dd:d9:dd:c25:c25:94de:f511
1382c19:dd:d9:dd:c25:c25:94de:f512/1272c19:dd:d9:dd:c25:c25:94de:f513
1392c19:dd:d9:dd:c25:c25:94de:f514/1272c19:dd:d9:dd:c25:c25:94de:f515
1402c19:dd:d9:dd:c25:c25:94de:f516/1272c19:dd:d9:dd:c25:c25:94de:f517
1412c19:dd:d9:dd:c25:c25:94de:f518/1272c19:dd:d9:dd:c25:c25:94de:f519
1422c19:dd:d9:dd:c25:c25:94de:f51a/1272c19:dd:d9:dd:c25:c25:94de:f51b
1432c19:dd:d9:dd:c25:c25:94de:f51c/1272c19:dd:d9:dd:c25:c25:94de:f51d
1442c19:dd:d9:dd:c25:c25:94de:f51e/1272c19:dd:d9:dd:c25:c25:94de:f51f
1452c19:dd:d9:dd:c25:c25:94de:f520/1272c19:dd:d9:dd:c25:c25:94de:f521
1462c19:dd:d9:dd:c25:c25:94de:f522/1272c19:dd:d9:dd:c25:c25:94de:f523
1472c19:dd:d9:dd:c25:c25:94de:f524/1272c19:dd:d9:dd:c25:c25:94de:f525
1482c19:dd:d9:dd:c25:c25:94de:f526/1272c19:dd:d9:dd:c25:c25:94de:f527
1492c19:dd:d9:dd:c25:c25:94de:f528/1272c19:dd:d9:dd:c25:c25:94de:f529
1502c19:dd:d9:dd:c25:c25:94de:f52a/1272c19:dd:d9:dd:c25:c25:94de:f52b
1512c19:dd:d9:dd:c25:c25:94de:f52c/1272c19:dd:d9:dd:c25:c25:94de:f52d
1522c19:dd:d9:dd:c25:c25:94de:f52e/1272c19:dd:d9:dd:c25:c25:94de:f52f
1532c19:dd:d9:dd:c25:c25:94de:f530/1272c19:dd:d9:dd:c25:c25:94de:f531
1542c19:dd:d9:dd:c25:c25:94de:f532/1272c19:dd:d9:dd:c25:c25:94de:f533
1552c19:dd:d9:dd:c25:c25:94de:f534/1272c19:dd:d9:dd:c25:c25:94de:f535
1562c19:dd:d9:dd:c25:c25:94de:f536/1272c19:dd:d9:dd:c25:c25:94de:f537
1572c19:dd:d9:dd:c25:c25:94de:f538/1272c19:dd:d9:dd:c25:c25:94de:f539
1582c19:dd:d9:dd:c25:c25:94de:f53a/1272c19:dd:d9:dd:c25:c25:94de:f53b
1592c19:dd:d9:dd:c25:c25:94de:f53c/1272c19:dd:d9:dd:c25:c25:94de:f53d
1602c19:dd:d9:dd:c25:c25:94de:f53e/1272c19:dd:d9:dd:c25:c25:94de:f53f
1612c19:dd:d9:dd:c25:c25:94de:f540/1272c19:dd:d9:dd:c25:c25:94de:f541
1622c19:dd:d9:dd:c25:c25:94de:f542/1272c19:dd:d9:dd:c25:c25:94de:f543
1632c19:dd:d9:dd:c25:c25:94de:f544/1272c19:dd:d9:dd:c25:c25:94de:f545
1642c19:dd:d9:dd:c25:c25:94de:f546/1272c19:dd:d9:dd:c25:c25:94de:f547
1652c19:dd:d9:dd:c25:c25:94de:f548/1272c19:dd:d9:dd:c25:c25:94de:f549
1662c19:dd:d9:dd:c25:c25:94de:f54a/1272c19:dd:d9:dd:c25:c25:94de:f54b
1672c19:dd:d9:dd:c25:c25:94de:f54c/1272c19:dd:d9:dd:c25:c25:94de:f54d
1682c19:dd:d9:dd:c25:c25:94de:f54e/1272c19:dd:d9:dd:c25:c25:94de:f54f
1692c19:dd:d9:dd:c25:c25:94de:f550/1272c19:dd:d9:dd:c25:c25:94de:f551
1702c19:dd:d9:dd:c25:c25:94de:f552/1272c19:dd:d9:dd:c25:c25:94de:f553
1712c19:dd:d9:dd:c25:c25:94de:f554/1272c19:dd:d9:dd:c25:c25:94de:f555
1722c19:dd:d9:dd:c25:c25:94de:f556/1272c19:dd:d9:dd:c25:c25:94de:f557
1732c19:dd:d9:dd:c25:c25:94de:f558/1272c19:dd:d9:dd:c25:c25:94de:f559
1742c19:dd:d9:dd:c25:c25:94de:f55a/1272c19:dd:d9:dd:c25:c25:94de:f55b
1752c19:dd:d9:dd:c25:c25:94de:f55c/1272c19:dd:d9:dd:c25:c25:94de:f55d
1762c19:dd:d9:dd:c25:c25:94de:f55e/1272c19:dd:d9:dd:c25:c25:94de:f55f
1772c19:dd:d9:dd:c25:c25:94de:f560/1272c19:dd:d9:dd:c25:c25:94de:f561
1782c19:dd:d9:dd:c25:c25:94de:f562/1272c19:dd:d9:dd:c25:c25:94de:f563
1792c19:dd:d9:dd:c25:c25:94de:f564/1272c19:dd:d9:dd:c25:c25:94de:f565
1802c19:dd:d9:dd:c25:c25:94de:f566/1272c19:dd:d9:dd:c25:c25:94de:f567
1812c19:dd:d9:dd:c25:c25:94de:f568/1272c19:dd:d9:dd:c25:c25:94de:f569
1822c19:dd:d9:dd:c25:c25:94de:f56a/1272c19:dd:d9:dd:c25:c25:94de:f56b
1832c19:dd:d9:dd:c25:c25:94de:f56c/1272c19:dd:d9:dd:c25:c25:94de:f56d
1842c19:dd:d9:dd:c25:c25:94de:f56e/1272c19:dd:d9:dd:c25:c25:94de:f56f
1852c19:dd:d9:dd:c25:c25:94de:f570/1272c19:dd:d9:dd:c25:c25:94de:f571
1862c19:dd:d9:dd:c25:c25:94de:f572/1272c19:dd:d9:dd:c25:c25:94de:f573
1872c19:dd:d9:dd:c25:c25:94de:f574/1272c19:dd:d9:dd:c25:c25:94de:f575
1882c19:dd:d9:dd:c25:c25:94de:f576/1272c19:dd:d9:dd:c25:c25:94de:f577
1892c19:dd:d9:dd:c25:c25:94de:f578/1272c19:dd:d9:dd:c25:c25:94de:f579
1902c19:dd:d9:dd:c25:c25:94de:f57a/1272c19:dd:d9:dd:c25:c25:94de:f57b
1912c19:dd:d9:dd:c25:c25:94de:f57c/1272c19:dd:d9:dd:c25:c25:94de:f57d
1922c19:dd:d9:dd:c25:c25:94de:f57e/1272c19:dd:d9:dd:c25:c25:94de:f57f
1932c19:dd:d9:dd:c25:c25:94de:f580/1272c19:dd:d9:dd:c25:c25:94de:f581
1942c19:dd:d9:dd:c25:c25:94de:f582/1272c19:dd:d9:dd:c25:c25:94de:f583
1952c19:dd:d9:dd:c25:c25:94de:f584/1272c19:dd:d9:dd:c25:c25:94de:f585
1962c19:dd:d9:dd:c25:c25:94de:f586/1272c19:dd:d9:dd:c25:c25:94de:f587
1972c19:dd:d9:dd:c25:c25:94de:f588/1272c19:dd:d9:dd:c25:c25:94de:f589
1982c19:dd:d9:dd:c25:c25:94de:f58a/1272c19:dd:d9:dd:c25:c25:94de:f58b
1992c19:dd:d9:dd:c25:c25:94de:f58c/1272c19:dd:d9:dd:c25:c25:94de:f58d
2002c19:dd:d9:dd:c25:c25:94de:f58e/1272c19:dd:d9:dd:c25:c25:94de:f58f
2012c19:dd:d9:dd:c25:c25:94de:f590/1272c19:dd:d9:dd:c25:c25:94de:f591
2022c19:dd:d9:dd:c25:c25:94de:f592/1272c19:dd:d9:dd:c25:c25:94de:f593
2032c19:dd:d9:dd:c25:c25:94de:f594/1272c19:dd:d9:dd:c25:c25:94de:f595
2042c19:dd:d9:dd:c25:c25:94de:f596/1272c19:dd:d9:dd:c25:c25:94de:f597
2052c19:dd:d9:dd:c25:c25:94de:f598/1272c19:dd:d9:dd:c25:c25:94de:f599
2062c19:dd:d9:dd:c25:c25:94de:f59a/1272c19:dd:d9:dd:c25:c25:94de:f59b
2072c19:dd:d9:dd:c25:c25:94de:f59c/1272c19:dd:d9:dd:c25:c25:94de:f59d
2082c19:dd:d9:dd:c25:c25:94de:f59e/1272c19:dd:d9:dd:c25:c25:94de:f59f
2092c19:dd:d9:dd:c25:c25:94de:f5a0/1272c19:dd:d9:dd:c25:c25:94de:f5a1
2102c19:dd:d9:dd:c25:c25:94de:f5a2/1272c19:dd:d9:dd:c25:c25:94de:f5a3
2112c19:dd:d9:dd:c25:c25:94de:f5a4/1272c19:dd:d9:dd:c25:c25:94de:f5a5
2122c19:dd:d9:dd:c25:c25:94de:f5a6/1272c19:dd:d9:dd:c25:c25:94de:f5a7
2132c19:dd:d9:dd:c25:c25:94de:f5a8/1272c19:dd:d9:dd:c25:c25:94de:f5a9
2142c19:dd:d9:dd:c25:c25:94de:f5aa/1272c19:dd:d9:dd:c25:c25:94de:f5ab
2152c19:dd:d9:dd:c25:c25:94de:f5ac/1272c19:dd:d9:dd:c25:c25:94de:f5ad
2162c19:dd:d9:dd:c25:c25:94de:f5ae/1272c19:dd:d9:dd:c25:c25:94de:f5af
2172c19:dd:d9:dd:c25:c25:94de:f5b0/1272c19:dd:d9:dd:c25:c25:94de:f5b1
2182c19:dd:d9:dd:c25:c25:94de:f5b2/1272c19:dd:d9:dd:c25:c25:94de:f5b3
2192c19:dd:d9:dd:c25:c25:94de:f5b4/1272c19:dd:d9:dd:c25:c25:94de:f5b5
2202c19:dd:d9:dd:c25:c25:94de:f5b6/1272c19:dd:d9:dd:c25:c25:94de:f5b7
2212c19:dd:d9:dd:c25:c25:94de:f5b8/1272c19:dd:d9:dd:c25:c25:94de:f5b9
2222c19:dd:d9:dd:c25:c25:94de:f5ba/1272c19:dd:d9:dd:c25:c25:94de:f5bb
2232c19:dd:d9:dd:c25:c25:94de:f5bc/1272c19:dd:d9:dd:c25:c25:94de:f5bd
2242c19:dd:d9:dd:c25:c25:94de:f5be/1272c19:dd:d9:dd:c25:c25:94de:f5bf
2252c19:dd:d9:dd:c25:c25:94de:f5c0/1272c19:dd:d9:dd:c25:c25:94de:f5c1
2262c19:dd:d9:dd:c25:c25:94de:f5c2/1272c19:dd:d9:dd:c25:c25:94de:f5c3
2272c19:dd:d9:dd:c25:c25:94de:f5c4/1272c19:dd:d9:dd:c25:c25:94de:f5c5
2282c19:dd:d9:dd:c25:c25:94de:f5c6/1272c19:dd:d9:dd:c25:c25:94de:f5c7
2292c19:dd:d9:dd:c25:c25:94de:f5c8/1272c19:dd:d9:dd:c25:c25:94de:f5c9
2302c19:dd:d9:dd:c25:c25:94de:f5ca/1272c19:dd:d9:dd:c25:c25:94de:f5cb
2312c19:dd:d9:dd:c25:c25:94de:f5cc/1272c19:dd:d9:dd:c25:c25:94de:f5cd
2322c19:dd:d9:dd:c25:c25:94de:f5ce/1272c19:dd:d9:dd:c25:c25:94de:f5cf
2332c19:dd:d9:dd:c25:c25:94de:f5d0/1272c19:dd:d9:dd:c25:c25:94de:f5d1
2342c19:dd:d9:dd:c25:c25:94de:f5d2/1272c19:dd:d9:dd:c25:c25:94de:f5d3
2352c19:dd:d9:dd:c25:c25:94de:f5d4/1272c19:dd:d9:dd:c25:c25:94de:f5d5
2362c19:dd:d9:dd:c25:c25:94de:f5d6/1272c19:dd:d9:dd:c25:c25:94de:f5d7
2372c19:dd:d9:dd:c25:c25:94de:f5d8/1272c19:dd:d9:dd:c25:c25:94de:f5d9
2382c19:dd:d9:dd:c25:c25:94de:f5da/1272c19:dd:d9:dd:c25:c25:94de:f5db
2392c19:dd:d9:dd:c25:c25:94de:f5dc/1272c19:dd:d9:dd:c25:c25:94de:f5dd
2402c19:dd:d9:dd:c25:c25:94de:f5de/1272c19:dd:d9:dd:c25:c25:94de:f5df
2412c19:dd:d9:dd:c25:c25:94de:f5e0/1272c19:dd:d9:dd:c25:c25:94de:f5e1
2422c19:dd:d9:dd:c25:c25:94de:f5e2/1272c19:dd:d9:dd:c25:c25:94de:f5e3
2432c19:dd:d9:dd:c25:c25:94de:f5e4/1272c19:dd:d9:dd:c25:c25:94de:f5e5
2442c19:dd:d9:dd:c25:c25:94de:f5e6/1272c19:dd:d9:dd:c25:c25:94de:f5e7
2452c19:dd:d9:dd:c25:c25:94de:f5e8/1272c19:dd:d9:dd:c25:c25:94de:f5e9
2462c19:dd:d9:dd:c25:c25:94de:f5ea/1272c19:dd:d9:dd:c25:c25:94de:f5eb
2472c19:dd:d9:dd:c25:c25:94de:f5ec/1272c19:dd:d9:dd:c25:c25:94de:f5ed
2482c19:dd:d9:dd:c25:c25:94de:f5ee/1272c19:dd:d9:dd:c25:c25:94de:f5ef
2492c19:dd:d9:dd:c25:c25:94de:f5f0/1272c19:dd:d9:dd:c25:c25:94de:f5f1
2502c19:dd:d9:dd:c25:c25:94de:f5f2/1272c19:dd:d9:dd:c25:c25:94de:f5f3
2512c19:dd:d9:dd:c25:c25:94de:f5f4/1272c19:dd:d9:dd:c25:c25:94de:f5f5
2522c19:dd:d9:dd:c25:c25:94de:f5f6/1272c19:dd:d9:dd:c25:c25:94de:f5f7
2532c19:dd:d9:dd:c25:c25:94de:f5f8/1272c19:dd:d9:dd:c25:c25:94de:f5f9
2542c19:dd:d9:dd:c25:c25:94de:f5fa/1272c19:dd:d9:dd:c25:c25:94de:f5fb
2552c19:dd:d9:dd:c25:c25:94de:f5fc/1272c19:dd:d9:dd:c25:c25:94de:f5fd
2562c19:dd:d9:dd:c25:c25:94de:f5fe/1272c19:dd:d9:dd:c25:c25:94de:f5ff

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.