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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/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25a:d00a:a300/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:a300
Last address
2c19:dd:d9:dd:c25:c25a:d00a:a3ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:a300
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.a.a.0.0.d.a.5.2.c.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25a:d00a:a300/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:a300/1282c19:dd:d9:dd:c25:c25a:d00a:a300
22c19:dd:d9:dd:c25:c25a:d00a:a301/1282c19:dd:d9:dd:c25:c25a:d00a:a301
32c19:dd:d9:dd:c25:c25a:d00a:a302/1282c19:dd:d9:dd:c25:c25a:d00a:a302
42c19:dd:d9:dd:c25:c25a:d00a:a303/1282c19:dd:d9:dd:c25:c25a:d00a:a303
52c19:dd:d9:dd:c25:c25a:d00a:a304/1282c19:dd:d9:dd:c25:c25a:d00a:a304
62c19:dd:d9:dd:c25:c25a:d00a:a305/1282c19:dd:d9:dd:c25:c25a:d00a:a305
72c19:dd:d9:dd:c25:c25a:d00a:a306/1282c19:dd:d9:dd:c25:c25a:d00a:a306
82c19:dd:d9:dd:c25:c25a:d00a:a307/1282c19:dd:d9:dd:c25:c25a:d00a:a307
92c19:dd:d9:dd:c25:c25a:d00a:a308/1282c19:dd:d9:dd:c25:c25a:d00a:a308
102c19:dd:d9:dd:c25:c25a:d00a:a309/1282c19:dd:d9:dd:c25:c25a:d00a:a309
112c19:dd:d9:dd:c25:c25a:d00a:a30a/1282c19:dd:d9:dd:c25:c25a:d00a:a30a
122c19:dd:d9:dd:c25:c25a:d00a:a30b/1282c19:dd:d9:dd:c25:c25a:d00a:a30b
132c19:dd:d9:dd:c25:c25a:d00a:a30c/1282c19:dd:d9:dd:c25:c25a:d00a:a30c
142c19:dd:d9:dd:c25:c25a:d00a:a30d/1282c19:dd:d9:dd:c25:c25a:d00a:a30d
152c19:dd:d9:dd:c25:c25a:d00a:a30e/1282c19:dd:d9:dd:c25:c25a:d00a:a30e
162c19:dd:d9:dd:c25:c25a:d00a:a30f/1282c19:dd:d9:dd:c25:c25a:d00a:a30f
172c19:dd:d9:dd:c25:c25a:d00a:a310/1282c19:dd:d9:dd:c25:c25a:d00a:a310
182c19:dd:d9:dd:c25:c25a:d00a:a311/1282c19:dd:d9:dd:c25:c25a:d00a:a311
192c19:dd:d9:dd:c25:c25a:d00a:a312/1282c19:dd:d9:dd:c25:c25a:d00a:a312
202c19:dd:d9:dd:c25:c25a:d00a:a313/1282c19:dd:d9:dd:c25:c25a:d00a:a313
212c19:dd:d9:dd:c25:c25a:d00a:a314/1282c19:dd:d9:dd:c25:c25a:d00a:a314
222c19:dd:d9:dd:c25:c25a:d00a:a315/1282c19:dd:d9:dd:c25:c25a:d00a:a315
232c19:dd:d9:dd:c25:c25a:d00a:a316/1282c19:dd:d9:dd:c25:c25a:d00a:a316
242c19:dd:d9:dd:c25:c25a:d00a:a317/1282c19:dd:d9:dd:c25:c25a:d00a:a317
252c19:dd:d9:dd:c25:c25a:d00a:a318/1282c19:dd:d9:dd:c25:c25a:d00a:a318
262c19:dd:d9:dd:c25:c25a:d00a:a319/1282c19:dd:d9:dd:c25:c25a:d00a:a319
272c19:dd:d9:dd:c25:c25a:d00a:a31a/1282c19:dd:d9:dd:c25:c25a:d00a:a31a
282c19:dd:d9:dd:c25:c25a:d00a:a31b/1282c19:dd:d9:dd:c25:c25a:d00a:a31b
292c19:dd:d9:dd:c25:c25a:d00a:a31c/1282c19:dd:d9:dd:c25:c25a:d00a:a31c
302c19:dd:d9:dd:c25:c25a:d00a:a31d/1282c19:dd:d9:dd:c25:c25a:d00a:a31d
312c19:dd:d9:dd:c25:c25a:d00a:a31e/1282c19:dd:d9:dd:c25:c25a:d00a:a31e
322c19:dd:d9:dd:c25:c25a:d00a:a31f/1282c19:dd:d9:dd:c25:c25a:d00a:a31f
332c19:dd:d9:dd:c25:c25a:d00a:a320/1282c19:dd:d9:dd:c25:c25a:d00a:a320
342c19:dd:d9:dd:c25:c25a:d00a:a321/1282c19:dd:d9:dd:c25:c25a:d00a:a321
352c19:dd:d9:dd:c25:c25a:d00a:a322/1282c19:dd:d9:dd:c25:c25a:d00a:a322
362c19:dd:d9:dd:c25:c25a:d00a:a323/1282c19:dd:d9:dd:c25:c25a:d00a:a323
372c19:dd:d9:dd:c25:c25a:d00a:a324/1282c19:dd:d9:dd:c25:c25a:d00a:a324
382c19:dd:d9:dd:c25:c25a:d00a:a325/1282c19:dd:d9:dd:c25:c25a:d00a:a325
392c19:dd:d9:dd:c25:c25a:d00a:a326/1282c19:dd:d9:dd:c25:c25a:d00a:a326
402c19:dd:d9:dd:c25:c25a:d00a:a327/1282c19:dd:d9:dd:c25:c25a:d00a:a327
412c19:dd:d9:dd:c25:c25a:d00a:a328/1282c19:dd:d9:dd:c25:c25a:d00a:a328
422c19:dd:d9:dd:c25:c25a:d00a:a329/1282c19:dd:d9:dd:c25:c25a:d00a:a329
432c19:dd:d9:dd:c25:c25a:d00a:a32a/1282c19:dd:d9:dd:c25:c25a:d00a:a32a
442c19:dd:d9:dd:c25:c25a:d00a:a32b/1282c19:dd:d9:dd:c25:c25a:d00a:a32b
452c19:dd:d9:dd:c25:c25a:d00a:a32c/1282c19:dd:d9:dd:c25:c25a:d00a:a32c
462c19:dd:d9:dd:c25:c25a:d00a:a32d/1282c19:dd:d9:dd:c25:c25a:d00a:a32d
472c19:dd:d9:dd:c25:c25a:d00a:a32e/1282c19:dd:d9:dd:c25:c25a:d00a:a32e
482c19:dd:d9:dd:c25:c25a:d00a:a32f/1282c19:dd:d9:dd:c25:c25a:d00a:a32f
492c19:dd:d9:dd:c25:c25a:d00a:a330/1282c19:dd:d9:dd:c25:c25a:d00a:a330
502c19:dd:d9:dd:c25:c25a:d00a:a331/1282c19:dd:d9:dd:c25:c25a:d00a:a331
512c19:dd:d9:dd:c25:c25a:d00a:a332/1282c19:dd:d9:dd:c25:c25a:d00a:a332
522c19:dd:d9:dd:c25:c25a:d00a:a333/1282c19:dd:d9:dd:c25:c25a:d00a:a333
532c19:dd:d9:dd:c25:c25a:d00a:a334/1282c19:dd:d9:dd:c25:c25a:d00a:a334
542c19:dd:d9:dd:c25:c25a:d00a:a335/1282c19:dd:d9:dd:c25:c25a:d00a:a335
552c19:dd:d9:dd:c25:c25a:d00a:a336/1282c19:dd:d9:dd:c25:c25a:d00a:a336
562c19:dd:d9:dd:c25:c25a:d00a:a337/1282c19:dd:d9:dd:c25:c25a:d00a:a337
572c19:dd:d9:dd:c25:c25a:d00a:a338/1282c19:dd:d9:dd:c25:c25a:d00a:a338
582c19:dd:d9:dd:c25:c25a:d00a:a339/1282c19:dd:d9:dd:c25:c25a:d00a:a339
592c19:dd:d9:dd:c25:c25a:d00a:a33a/1282c19:dd:d9:dd:c25:c25a:d00a:a33a
602c19:dd:d9:dd:c25:c25a:d00a:a33b/1282c19:dd:d9:dd:c25:c25a:d00a:a33b
612c19:dd:d9:dd:c25:c25a:d00a:a33c/1282c19:dd:d9:dd:c25:c25a:d00a:a33c
622c19:dd:d9:dd:c25:c25a:d00a:a33d/1282c19:dd:d9:dd:c25:c25a:d00a:a33d
632c19:dd:d9:dd:c25:c25a:d00a:a33e/1282c19:dd:d9:dd:c25:c25a:d00a:a33e
642c19:dd:d9:dd:c25:c25a:d00a:a33f/1282c19:dd:d9:dd:c25:c25a:d00a:a33f
652c19:dd:d9:dd:c25:c25a:d00a:a340/1282c19:dd:d9:dd:c25:c25a:d00a:a340
662c19:dd:d9:dd:c25:c25a:d00a:a341/1282c19:dd:d9:dd:c25:c25a:d00a:a341
672c19:dd:d9:dd:c25:c25a:d00a:a342/1282c19:dd:d9:dd:c25:c25a:d00a:a342
682c19:dd:d9:dd:c25:c25a:d00a:a343/1282c19:dd:d9:dd:c25:c25a:d00a:a343
692c19:dd:d9:dd:c25:c25a:d00a:a344/1282c19:dd:d9:dd:c25:c25a:d00a:a344
702c19:dd:d9:dd:c25:c25a:d00a:a345/1282c19:dd:d9:dd:c25:c25a:d00a:a345
712c19:dd:d9:dd:c25:c25a:d00a:a346/1282c19:dd:d9:dd:c25:c25a:d00a:a346
722c19:dd:d9:dd:c25:c25a:d00a:a347/1282c19:dd:d9:dd:c25:c25a:d00a:a347
732c19:dd:d9:dd:c25:c25a:d00a:a348/1282c19:dd:d9:dd:c25:c25a:d00a:a348
742c19:dd:d9:dd:c25:c25a:d00a:a349/1282c19:dd:d9:dd:c25:c25a:d00a:a349
752c19:dd:d9:dd:c25:c25a:d00a:a34a/1282c19:dd:d9:dd:c25:c25a:d00a:a34a
762c19:dd:d9:dd:c25:c25a:d00a:a34b/1282c19:dd:d9:dd:c25:c25a:d00a:a34b
772c19:dd:d9:dd:c25:c25a:d00a:a34c/1282c19:dd:d9:dd:c25:c25a:d00a:a34c
782c19:dd:d9:dd:c25:c25a:d00a:a34d/1282c19:dd:d9:dd:c25:c25a:d00a:a34d
792c19:dd:d9:dd:c25:c25a:d00a:a34e/1282c19:dd:d9:dd:c25:c25a:d00a:a34e
802c19:dd:d9:dd:c25:c25a:d00a:a34f/1282c19:dd:d9:dd:c25:c25a:d00a:a34f
812c19:dd:d9:dd:c25:c25a:d00a:a350/1282c19:dd:d9:dd:c25:c25a:d00a:a350
822c19:dd:d9:dd:c25:c25a:d00a:a351/1282c19:dd:d9:dd:c25:c25a:d00a:a351
832c19:dd:d9:dd:c25:c25a:d00a:a352/1282c19:dd:d9:dd:c25:c25a:d00a:a352
842c19:dd:d9:dd:c25:c25a:d00a:a353/1282c19:dd:d9:dd:c25:c25a:d00a:a353
852c19:dd:d9:dd:c25:c25a:d00a:a354/1282c19:dd:d9:dd:c25:c25a:d00a:a354
862c19:dd:d9:dd:c25:c25a:d00a:a355/1282c19:dd:d9:dd:c25:c25a:d00a:a355
872c19:dd:d9:dd:c25:c25a:d00a:a356/1282c19:dd:d9:dd:c25:c25a:d00a:a356
882c19:dd:d9:dd:c25:c25a:d00a:a357/1282c19:dd:d9:dd:c25:c25a:d00a:a357
892c19:dd:d9:dd:c25:c25a:d00a:a358/1282c19:dd:d9:dd:c25:c25a:d00a:a358
902c19:dd:d9:dd:c25:c25a:d00a:a359/1282c19:dd:d9:dd:c25:c25a:d00a:a359
912c19:dd:d9:dd:c25:c25a:d00a:a35a/1282c19:dd:d9:dd:c25:c25a:d00a:a35a
922c19:dd:d9:dd:c25:c25a:d00a:a35b/1282c19:dd:d9:dd:c25:c25a:d00a:a35b
932c19:dd:d9:dd:c25:c25a:d00a:a35c/1282c19:dd:d9:dd:c25:c25a:d00a:a35c
942c19:dd:d9:dd:c25:c25a:d00a:a35d/1282c19:dd:d9:dd:c25:c25a:d00a:a35d
952c19:dd:d9:dd:c25:c25a:d00a:a35e/1282c19:dd:d9:dd:c25:c25a:d00a:a35e
962c19:dd:d9:dd:c25:c25a:d00a:a35f/1282c19:dd:d9:dd:c25:c25a:d00a:a35f
972c19:dd:d9:dd:c25:c25a:d00a:a360/1282c19:dd:d9:dd:c25:c25a:d00a:a360
982c19:dd:d9:dd:c25:c25a:d00a:a361/1282c19:dd:d9:dd:c25:c25a:d00a:a361
992c19:dd:d9:dd:c25:c25a:d00a:a362/1282c19:dd:d9:dd:c25:c25a:d00a:a362
1002c19:dd:d9:dd:c25:c25a:d00a:a363/1282c19:dd:d9:dd:c25:c25a:d00a:a363
1012c19:dd:d9:dd:c25:c25a:d00a:a364/1282c19:dd:d9:dd:c25:c25a:d00a:a364
1022c19:dd:d9:dd:c25:c25a:d00a:a365/1282c19:dd:d9:dd:c25:c25a:d00a:a365
1032c19:dd:d9:dd:c25:c25a:d00a:a366/1282c19:dd:d9:dd:c25:c25a:d00a:a366
1042c19:dd:d9:dd:c25:c25a:d00a:a367/1282c19:dd:d9:dd:c25:c25a:d00a:a367
1052c19:dd:d9:dd:c25:c25a:d00a:a368/1282c19:dd:d9:dd:c25:c25a:d00a:a368
1062c19:dd:d9:dd:c25:c25a:d00a:a369/1282c19:dd:d9:dd:c25:c25a:d00a:a369
1072c19:dd:d9:dd:c25:c25a:d00a:a36a/1282c19:dd:d9:dd:c25:c25a:d00a:a36a
1082c19:dd:d9:dd:c25:c25a:d00a:a36b/1282c19:dd:d9:dd:c25:c25a:d00a:a36b
1092c19:dd:d9:dd:c25:c25a:d00a:a36c/1282c19:dd:d9:dd:c25:c25a:d00a:a36c
1102c19:dd:d9:dd:c25:c25a:d00a:a36d/1282c19:dd:d9:dd:c25:c25a:d00a:a36d
1112c19:dd:d9:dd:c25:c25a:d00a:a36e/1282c19:dd:d9:dd:c25:c25a:d00a:a36e
1122c19:dd:d9:dd:c25:c25a:d00a:a36f/1282c19:dd:d9:dd:c25:c25a:d00a:a36f
1132c19:dd:d9:dd:c25:c25a:d00a:a370/1282c19:dd:d9:dd:c25:c25a:d00a:a370
1142c19:dd:d9:dd:c25:c25a:d00a:a371/1282c19:dd:d9:dd:c25:c25a:d00a:a371
1152c19:dd:d9:dd:c25:c25a:d00a:a372/1282c19:dd:d9:dd:c25:c25a:d00a:a372
1162c19:dd:d9:dd:c25:c25a:d00a:a373/1282c19:dd:d9:dd:c25:c25a:d00a:a373
1172c19:dd:d9:dd:c25:c25a:d00a:a374/1282c19:dd:d9:dd:c25:c25a:d00a:a374
1182c19:dd:d9:dd:c25:c25a:d00a:a375/1282c19:dd:d9:dd:c25:c25a:d00a:a375
1192c19:dd:d9:dd:c25:c25a:d00a:a376/1282c19:dd:d9:dd:c25:c25a:d00a:a376
1202c19:dd:d9:dd:c25:c25a:d00a:a377/1282c19:dd:d9:dd:c25:c25a:d00a:a377
1212c19:dd:d9:dd:c25:c25a:d00a:a378/1282c19:dd:d9:dd:c25:c25a:d00a:a378
1222c19:dd:d9:dd:c25:c25a:d00a:a379/1282c19:dd:d9:dd:c25:c25a:d00a:a379
1232c19:dd:d9:dd:c25:c25a:d00a:a37a/1282c19:dd:d9:dd:c25:c25a:d00a:a37a
1242c19:dd:d9:dd:c25:c25a:d00a:a37b/1282c19:dd:d9:dd:c25:c25a:d00a:a37b
1252c19:dd:d9:dd:c25:c25a:d00a:a37c/1282c19:dd:d9:dd:c25:c25a:d00a:a37c
1262c19:dd:d9:dd:c25:c25a:d00a:a37d/1282c19:dd:d9:dd:c25:c25a:d00a:a37d
1272c19:dd:d9:dd:c25:c25a:d00a:a37e/1282c19:dd:d9:dd:c25:c25a:d00a:a37e
1282c19:dd:d9:dd:c25:c25a:d00a:a37f/1282c19:dd:d9:dd:c25:c25a:d00a:a37f
1292c19:dd:d9:dd:c25:c25a:d00a:a380/1282c19:dd:d9:dd:c25:c25a:d00a:a380
1302c19:dd:d9:dd:c25:c25a:d00a:a381/1282c19:dd:d9:dd:c25:c25a:d00a:a381
1312c19:dd:d9:dd:c25:c25a:d00a:a382/1282c19:dd:d9:dd:c25:c25a:d00a:a382
1322c19:dd:d9:dd:c25:c25a:d00a:a383/1282c19:dd:d9:dd:c25:c25a:d00a:a383
1332c19:dd:d9:dd:c25:c25a:d00a:a384/1282c19:dd:d9:dd:c25:c25a:d00a:a384
1342c19:dd:d9:dd:c25:c25a:d00a:a385/1282c19:dd:d9:dd:c25:c25a:d00a:a385
1352c19:dd:d9:dd:c25:c25a:d00a:a386/1282c19:dd:d9:dd:c25:c25a:d00a:a386
1362c19:dd:d9:dd:c25:c25a:d00a:a387/1282c19:dd:d9:dd:c25:c25a:d00a:a387
1372c19:dd:d9:dd:c25:c25a:d00a:a388/1282c19:dd:d9:dd:c25:c25a:d00a:a388
1382c19:dd:d9:dd:c25:c25a:d00a:a389/1282c19:dd:d9:dd:c25:c25a:d00a:a389
1392c19:dd:d9:dd:c25:c25a:d00a:a38a/1282c19:dd:d9:dd:c25:c25a:d00a:a38a
1402c19:dd:d9:dd:c25:c25a:d00a:a38b/1282c19:dd:d9:dd:c25:c25a:d00a:a38b
1412c19:dd:d9:dd:c25:c25a:d00a:a38c/1282c19:dd:d9:dd:c25:c25a:d00a:a38c
1422c19:dd:d9:dd:c25:c25a:d00a:a38d/1282c19:dd:d9:dd:c25:c25a:d00a:a38d
1432c19:dd:d9:dd:c25:c25a:d00a:a38e/1282c19:dd:d9:dd:c25:c25a:d00a:a38e
1442c19:dd:d9:dd:c25:c25a:d00a:a38f/1282c19:dd:d9:dd:c25:c25a:d00a:a38f
1452c19:dd:d9:dd:c25:c25a:d00a:a390/1282c19:dd:d9:dd:c25:c25a:d00a:a390
1462c19:dd:d9:dd:c25:c25a:d00a:a391/1282c19:dd:d9:dd:c25:c25a:d00a:a391
1472c19:dd:d9:dd:c25:c25a:d00a:a392/1282c19:dd:d9:dd:c25:c25a:d00a:a392
1482c19:dd:d9:dd:c25:c25a:d00a:a393/1282c19:dd:d9:dd:c25:c25a:d00a:a393
1492c19:dd:d9:dd:c25:c25a:d00a:a394/1282c19:dd:d9:dd:c25:c25a:d00a:a394
1502c19:dd:d9:dd:c25:c25a:d00a:a395/1282c19:dd:d9:dd:c25:c25a:d00a:a395
1512c19:dd:d9:dd:c25:c25a:d00a:a396/1282c19:dd:d9:dd:c25:c25a:d00a:a396
1522c19:dd:d9:dd:c25:c25a:d00a:a397/1282c19:dd:d9:dd:c25:c25a:d00a:a397
1532c19:dd:d9:dd:c25:c25a:d00a:a398/1282c19:dd:d9:dd:c25:c25a:d00a:a398
1542c19:dd:d9:dd:c25:c25a:d00a:a399/1282c19:dd:d9:dd:c25:c25a:d00a:a399
1552c19:dd:d9:dd:c25:c25a:d00a:a39a/1282c19:dd:d9:dd:c25:c25a:d00a:a39a
1562c19:dd:d9:dd:c25:c25a:d00a:a39b/1282c19:dd:d9:dd:c25:c25a:d00a:a39b
1572c19:dd:d9:dd:c25:c25a:d00a:a39c/1282c19:dd:d9:dd:c25:c25a:d00a:a39c
1582c19:dd:d9:dd:c25:c25a:d00a:a39d/1282c19:dd:d9:dd:c25:c25a:d00a:a39d
1592c19:dd:d9:dd:c25:c25a:d00a:a39e/1282c19:dd:d9:dd:c25:c25a:d00a:a39e
1602c19:dd:d9:dd:c25:c25a:d00a:a39f/1282c19:dd:d9:dd:c25:c25a:d00a:a39f
1612c19:dd:d9:dd:c25:c25a:d00a:a3a0/1282c19:dd:d9:dd:c25:c25a:d00a:a3a0
1622c19:dd:d9:dd:c25:c25a:d00a:a3a1/1282c19:dd:d9:dd:c25:c25a:d00a:a3a1
1632c19:dd:d9:dd:c25:c25a:d00a:a3a2/1282c19:dd:d9:dd:c25:c25a:d00a:a3a2
1642c19:dd:d9:dd:c25:c25a:d00a:a3a3/1282c19:dd:d9:dd:c25:c25a:d00a:a3a3
1652c19:dd:d9:dd:c25:c25a:d00a:a3a4/1282c19:dd:d9:dd:c25:c25a:d00a:a3a4
1662c19:dd:d9:dd:c25:c25a:d00a:a3a5/1282c19:dd:d9:dd:c25:c25a:d00a:a3a5
1672c19:dd:d9:dd:c25:c25a:d00a:a3a6/1282c19:dd:d9:dd:c25:c25a:d00a:a3a6
1682c19:dd:d9:dd:c25:c25a:d00a:a3a7/1282c19:dd:d9:dd:c25:c25a:d00a:a3a7
1692c19:dd:d9:dd:c25:c25a:d00a:a3a8/1282c19:dd:d9:dd:c25:c25a:d00a:a3a8
1702c19:dd:d9:dd:c25:c25a:d00a:a3a9/1282c19:dd:d9:dd:c25:c25a:d00a:a3a9
1712c19:dd:d9:dd:c25:c25a:d00a:a3aa/1282c19:dd:d9:dd:c25:c25a:d00a:a3aa
1722c19:dd:d9:dd:c25:c25a:d00a:a3ab/1282c19:dd:d9:dd:c25:c25a:d00a:a3ab
1732c19:dd:d9:dd:c25:c25a:d00a:a3ac/1282c19:dd:d9:dd:c25:c25a:d00a:a3ac
1742c19:dd:d9:dd:c25:c25a:d00a:a3ad/1282c19:dd:d9:dd:c25:c25a:d00a:a3ad
1752c19:dd:d9:dd:c25:c25a:d00a:a3ae/1282c19:dd:d9:dd:c25:c25a:d00a:a3ae
1762c19:dd:d9:dd:c25:c25a:d00a:a3af/1282c19:dd:d9:dd:c25:c25a:d00a:a3af
1772c19:dd:d9:dd:c25:c25a:d00a:a3b0/1282c19:dd:d9:dd:c25:c25a:d00a:a3b0
1782c19:dd:d9:dd:c25:c25a:d00a:a3b1/1282c19:dd:d9:dd:c25:c25a:d00a:a3b1
1792c19:dd:d9:dd:c25:c25a:d00a:a3b2/1282c19:dd:d9:dd:c25:c25a:d00a:a3b2
1802c19:dd:d9:dd:c25:c25a:d00a:a3b3/1282c19:dd:d9:dd:c25:c25a:d00a:a3b3
1812c19:dd:d9:dd:c25:c25a:d00a:a3b4/1282c19:dd:d9:dd:c25:c25a:d00a:a3b4
1822c19:dd:d9:dd:c25:c25a:d00a:a3b5/1282c19:dd:d9:dd:c25:c25a:d00a:a3b5
1832c19:dd:d9:dd:c25:c25a:d00a:a3b6/1282c19:dd:d9:dd:c25:c25a:d00a:a3b6
1842c19:dd:d9:dd:c25:c25a:d00a:a3b7/1282c19:dd:d9:dd:c25:c25a:d00a:a3b7
1852c19:dd:d9:dd:c25:c25a:d00a:a3b8/1282c19:dd:d9:dd:c25:c25a:d00a:a3b8
1862c19:dd:d9:dd:c25:c25a:d00a:a3b9/1282c19:dd:d9:dd:c25:c25a:d00a:a3b9
1872c19:dd:d9:dd:c25:c25a:d00a:a3ba/1282c19:dd:d9:dd:c25:c25a:d00a:a3ba
1882c19:dd:d9:dd:c25:c25a:d00a:a3bb/1282c19:dd:d9:dd:c25:c25a:d00a:a3bb
1892c19:dd:d9:dd:c25:c25a:d00a:a3bc/1282c19:dd:d9:dd:c25:c25a:d00a:a3bc
1902c19:dd:d9:dd:c25:c25a:d00a:a3bd/1282c19:dd:d9:dd:c25:c25a:d00a:a3bd
1912c19:dd:d9:dd:c25:c25a:d00a:a3be/1282c19:dd:d9:dd:c25:c25a:d00a:a3be
1922c19:dd:d9:dd:c25:c25a:d00a:a3bf/1282c19:dd:d9:dd:c25:c25a:d00a:a3bf
1932c19:dd:d9:dd:c25:c25a:d00a:a3c0/1282c19:dd:d9:dd:c25:c25a:d00a:a3c0
1942c19:dd:d9:dd:c25:c25a:d00a:a3c1/1282c19:dd:d9:dd:c25:c25a:d00a:a3c1
1952c19:dd:d9:dd:c25:c25a:d00a:a3c2/1282c19:dd:d9:dd:c25:c25a:d00a:a3c2
1962c19:dd:d9:dd:c25:c25a:d00a:a3c3/1282c19:dd:d9:dd:c25:c25a:d00a:a3c3
1972c19:dd:d9:dd:c25:c25a:d00a:a3c4/1282c19:dd:d9:dd:c25:c25a:d00a:a3c4
1982c19:dd:d9:dd:c25:c25a:d00a:a3c5/1282c19:dd:d9:dd:c25:c25a:d00a:a3c5
1992c19:dd:d9:dd:c25:c25a:d00a:a3c6/1282c19:dd:d9:dd:c25:c25a:d00a:a3c6
2002c19:dd:d9:dd:c25:c25a:d00a:a3c7/1282c19:dd:d9:dd:c25:c25a:d00a:a3c7
2012c19:dd:d9:dd:c25:c25a:d00a:a3c8/1282c19:dd:d9:dd:c25:c25a:d00a:a3c8
2022c19:dd:d9:dd:c25:c25a:d00a:a3c9/1282c19:dd:d9:dd:c25:c25a:d00a:a3c9
2032c19:dd:d9:dd:c25:c25a:d00a:a3ca/1282c19:dd:d9:dd:c25:c25a:d00a:a3ca
2042c19:dd:d9:dd:c25:c25a:d00a:a3cb/1282c19:dd:d9:dd:c25:c25a:d00a:a3cb
2052c19:dd:d9:dd:c25:c25a:d00a:a3cc/1282c19:dd:d9:dd:c25:c25a:d00a:a3cc
2062c19:dd:d9:dd:c25:c25a:d00a:a3cd/1282c19:dd:d9:dd:c25:c25a:d00a:a3cd
2072c19:dd:d9:dd:c25:c25a:d00a:a3ce/1282c19:dd:d9:dd:c25:c25a:d00a:a3ce
2082c19:dd:d9:dd:c25:c25a:d00a:a3cf/1282c19:dd:d9:dd:c25:c25a:d00a:a3cf
2092c19:dd:d9:dd:c25:c25a:d00a:a3d0/1282c19:dd:d9:dd:c25:c25a:d00a:a3d0
2102c19:dd:d9:dd:c25:c25a:d00a:a3d1/1282c19:dd:d9:dd:c25:c25a:d00a:a3d1
2112c19:dd:d9:dd:c25:c25a:d00a:a3d2/1282c19:dd:d9:dd:c25:c25a:d00a:a3d2
2122c19:dd:d9:dd:c25:c25a:d00a:a3d3/1282c19:dd:d9:dd:c25:c25a:d00a:a3d3
2132c19:dd:d9:dd:c25:c25a:d00a:a3d4/1282c19:dd:d9:dd:c25:c25a:d00a:a3d4
2142c19:dd:d9:dd:c25:c25a:d00a:a3d5/1282c19:dd:d9:dd:c25:c25a:d00a:a3d5
2152c19:dd:d9:dd:c25:c25a:d00a:a3d6/1282c19:dd:d9:dd:c25:c25a:d00a:a3d6
2162c19:dd:d9:dd:c25:c25a:d00a:a3d7/1282c19:dd:d9:dd:c25:c25a:d00a:a3d7
2172c19:dd:d9:dd:c25:c25a:d00a:a3d8/1282c19:dd:d9:dd:c25:c25a:d00a:a3d8
2182c19:dd:d9:dd:c25:c25a:d00a:a3d9/1282c19:dd:d9:dd:c25:c25a:d00a:a3d9
2192c19:dd:d9:dd:c25:c25a:d00a:a3da/1282c19:dd:d9:dd:c25:c25a:d00a:a3da
2202c19:dd:d9:dd:c25:c25a:d00a:a3db/1282c19:dd:d9:dd:c25:c25a:d00a:a3db
2212c19:dd:d9:dd:c25:c25a:d00a:a3dc/1282c19:dd:d9:dd:c25:c25a:d00a:a3dc
2222c19:dd:d9:dd:c25:c25a:d00a:a3dd/1282c19:dd:d9:dd:c25:c25a:d00a:a3dd
2232c19:dd:d9:dd:c25:c25a:d00a:a3de/1282c19:dd:d9:dd:c25:c25a:d00a:a3de
2242c19:dd:d9:dd:c25:c25a:d00a:a3df/1282c19:dd:d9:dd:c25:c25a:d00a:a3df
2252c19:dd:d9:dd:c25:c25a:d00a:a3e0/1282c19:dd:d9:dd:c25:c25a:d00a:a3e0
2262c19:dd:d9:dd:c25:c25a:d00a:a3e1/1282c19:dd:d9:dd:c25:c25a:d00a:a3e1
2272c19:dd:d9:dd:c25:c25a:d00a:a3e2/1282c19:dd:d9:dd:c25:c25a:d00a:a3e2
2282c19:dd:d9:dd:c25:c25a:d00a:a3e3/1282c19:dd:d9:dd:c25:c25a:d00a:a3e3
2292c19:dd:d9:dd:c25:c25a:d00a:a3e4/1282c19:dd:d9:dd:c25:c25a:d00a:a3e4
2302c19:dd:d9:dd:c25:c25a:d00a:a3e5/1282c19:dd:d9:dd:c25:c25a:d00a:a3e5
2312c19:dd:d9:dd:c25:c25a:d00a:a3e6/1282c19:dd:d9:dd:c25:c25a:d00a:a3e6
2322c19:dd:d9:dd:c25:c25a:d00a:a3e7/1282c19:dd:d9:dd:c25:c25a:d00a:a3e7
2332c19:dd:d9:dd:c25:c25a:d00a:a3e8/1282c19:dd:d9:dd:c25:c25a:d00a:a3e8
2342c19:dd:d9:dd:c25:c25a:d00a:a3e9/1282c19:dd:d9:dd:c25:c25a:d00a:a3e9
2352c19:dd:d9:dd:c25:c25a:d00a:a3ea/1282c19:dd:d9:dd:c25:c25a:d00a:a3ea
2362c19:dd:d9:dd:c25:c25a:d00a:a3eb/1282c19:dd:d9:dd:c25:c25a:d00a:a3eb
2372c19:dd:d9:dd:c25:c25a:d00a:a3ec/1282c19:dd:d9:dd:c25:c25a:d00a:a3ec
2382c19:dd:d9:dd:c25:c25a:d00a:a3ed/1282c19:dd:d9:dd:c25:c25a:d00a:a3ed
2392c19:dd:d9:dd:c25:c25a:d00a:a3ee/1282c19:dd:d9:dd:c25:c25a:d00a:a3ee
2402c19:dd:d9:dd:c25:c25a:d00a:a3ef/1282c19:dd:d9:dd:c25:c25a:d00a:a3ef
2412c19:dd:d9:dd:c25:c25a:d00a:a3f0/1282c19:dd:d9:dd:c25:c25a:d00a:a3f0
2422c19:dd:d9:dd:c25:c25a:d00a:a3f1/1282c19:dd:d9:dd:c25:c25a:d00a:a3f1
2432c19:dd:d9:dd:c25:c25a:d00a:a3f2/1282c19:dd:d9:dd:c25:c25a:d00a:a3f2
2442c19:dd:d9:dd:c25:c25a:d00a:a3f3/1282c19:dd:d9:dd:c25:c25a:d00a:a3f3
2452c19:dd:d9:dd:c25:c25a:d00a:a3f4/1282c19:dd:d9:dd:c25:c25a:d00a:a3f4
2462c19:dd:d9:dd:c25:c25a:d00a:a3f5/1282c19:dd:d9:dd:c25:c25a:d00a:a3f5
2472c19:dd:d9:dd:c25:c25a:d00a:a3f6/1282c19:dd:d9:dd:c25:c25a:d00a:a3f6
2482c19:dd:d9:dd:c25:c25a:d00a:a3f7/1282c19:dd:d9:dd:c25:c25a:d00a:a3f7
2492c19:dd:d9:dd:c25:c25a:d00a:a3f8/1282c19:dd:d9:dd:c25:c25a:d00a:a3f8
2502c19:dd:d9:dd:c25:c25a:d00a:a3f9/1282c19:dd:d9:dd:c25:c25a:d00a:a3f9
2512c19:dd:d9:dd:c25:c25a:d00a:a3fa/1282c19:dd:d9:dd:c25:c25a:d00a:a3fa
2522c19:dd:d9:dd:c25:c25a:d00a:a3fb/1282c19:dd:d9:dd:c25:c25a:d00a:a3fb
2532c19:dd:d9:dd:c25:c25a:d00a:a3fc/1282c19:dd:d9:dd:c25:c25a:d00a:a3fc
2542c19:dd:d9:dd:c25:c25a:d00a:a3fd/1282c19:dd:d9:dd:c25:c25a:d00a:a3fd
2552c19:dd:d9:dd:c25:c25a:d00a:a3fe/1282c19:dd:d9:dd:c25:c25a:d00a:a3fe
2562c19:dd:d9:dd:c25:c25a:d00a:a3ff/1282c19:dd:d9:dd:c25:c25a:d00a:a3ff

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.