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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:d300/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:d300
Last address
2c19:dd:d9:dd:c25:c25a:d00a:d3ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:d300
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.d.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:d300/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:d300/1282c19:dd:d9:dd:c25:c25a:d00a:d300
22c19:dd:d9:dd:c25:c25a:d00a:d301/1282c19:dd:d9:dd:c25:c25a:d00a:d301
32c19:dd:d9:dd:c25:c25a:d00a:d302/1282c19:dd:d9:dd:c25:c25a:d00a:d302
42c19:dd:d9:dd:c25:c25a:d00a:d303/1282c19:dd:d9:dd:c25:c25a:d00a:d303
52c19:dd:d9:dd:c25:c25a:d00a:d304/1282c19:dd:d9:dd:c25:c25a:d00a:d304
62c19:dd:d9:dd:c25:c25a:d00a:d305/1282c19:dd:d9:dd:c25:c25a:d00a:d305
72c19:dd:d9:dd:c25:c25a:d00a:d306/1282c19:dd:d9:dd:c25:c25a:d00a:d306
82c19:dd:d9:dd:c25:c25a:d00a:d307/1282c19:dd:d9:dd:c25:c25a:d00a:d307
92c19:dd:d9:dd:c25:c25a:d00a:d308/1282c19:dd:d9:dd:c25:c25a:d00a:d308
102c19:dd:d9:dd:c25:c25a:d00a:d309/1282c19:dd:d9:dd:c25:c25a:d00a:d309
112c19:dd:d9:dd:c25:c25a:d00a:d30a/1282c19:dd:d9:dd:c25:c25a:d00a:d30a
122c19:dd:d9:dd:c25:c25a:d00a:d30b/1282c19:dd:d9:dd:c25:c25a:d00a:d30b
132c19:dd:d9:dd:c25:c25a:d00a:d30c/1282c19:dd:d9:dd:c25:c25a:d00a:d30c
142c19:dd:d9:dd:c25:c25a:d00a:d30d/1282c19:dd:d9:dd:c25:c25a:d00a:d30d
152c19:dd:d9:dd:c25:c25a:d00a:d30e/1282c19:dd:d9:dd:c25:c25a:d00a:d30e
162c19:dd:d9:dd:c25:c25a:d00a:d30f/1282c19:dd:d9:dd:c25:c25a:d00a:d30f
172c19:dd:d9:dd:c25:c25a:d00a:d310/1282c19:dd:d9:dd:c25:c25a:d00a:d310
182c19:dd:d9:dd:c25:c25a:d00a:d311/1282c19:dd:d9:dd:c25:c25a:d00a:d311
192c19:dd:d9:dd:c25:c25a:d00a:d312/1282c19:dd:d9:dd:c25:c25a:d00a:d312
202c19:dd:d9:dd:c25:c25a:d00a:d313/1282c19:dd:d9:dd:c25:c25a:d00a:d313
212c19:dd:d9:dd:c25:c25a:d00a:d314/1282c19:dd:d9:dd:c25:c25a:d00a:d314
222c19:dd:d9:dd:c25:c25a:d00a:d315/1282c19:dd:d9:dd:c25:c25a:d00a:d315
232c19:dd:d9:dd:c25:c25a:d00a:d316/1282c19:dd:d9:dd:c25:c25a:d00a:d316
242c19:dd:d9:dd:c25:c25a:d00a:d317/1282c19:dd:d9:dd:c25:c25a:d00a:d317
252c19:dd:d9:dd:c25:c25a:d00a:d318/1282c19:dd:d9:dd:c25:c25a:d00a:d318
262c19:dd:d9:dd:c25:c25a:d00a:d319/1282c19:dd:d9:dd:c25:c25a:d00a:d319
272c19:dd:d9:dd:c25:c25a:d00a:d31a/1282c19:dd:d9:dd:c25:c25a:d00a:d31a
282c19:dd:d9:dd:c25:c25a:d00a:d31b/1282c19:dd:d9:dd:c25:c25a:d00a:d31b
292c19:dd:d9:dd:c25:c25a:d00a:d31c/1282c19:dd:d9:dd:c25:c25a:d00a:d31c
302c19:dd:d9:dd:c25:c25a:d00a:d31d/1282c19:dd:d9:dd:c25:c25a:d00a:d31d
312c19:dd:d9:dd:c25:c25a:d00a:d31e/1282c19:dd:d9:dd:c25:c25a:d00a:d31e
322c19:dd:d9:dd:c25:c25a:d00a:d31f/1282c19:dd:d9:dd:c25:c25a:d00a:d31f
332c19:dd:d9:dd:c25:c25a:d00a:d320/1282c19:dd:d9:dd:c25:c25a:d00a:d320
342c19:dd:d9:dd:c25:c25a:d00a:d321/1282c19:dd:d9:dd:c25:c25a:d00a:d321
352c19:dd:d9:dd:c25:c25a:d00a:d322/1282c19:dd:d9:dd:c25:c25a:d00a:d322
362c19:dd:d9:dd:c25:c25a:d00a:d323/1282c19:dd:d9:dd:c25:c25a:d00a:d323
372c19:dd:d9:dd:c25:c25a:d00a:d324/1282c19:dd:d9:dd:c25:c25a:d00a:d324
382c19:dd:d9:dd:c25:c25a:d00a:d325/1282c19:dd:d9:dd:c25:c25a:d00a:d325
392c19:dd:d9:dd:c25:c25a:d00a:d326/1282c19:dd:d9:dd:c25:c25a:d00a:d326
402c19:dd:d9:dd:c25:c25a:d00a:d327/1282c19:dd:d9:dd:c25:c25a:d00a:d327
412c19:dd:d9:dd:c25:c25a:d00a:d328/1282c19:dd:d9:dd:c25:c25a:d00a:d328
422c19:dd:d9:dd:c25:c25a:d00a:d329/1282c19:dd:d9:dd:c25:c25a:d00a:d329
432c19:dd:d9:dd:c25:c25a:d00a:d32a/1282c19:dd:d9:dd:c25:c25a:d00a:d32a
442c19:dd:d9:dd:c25:c25a:d00a:d32b/1282c19:dd:d9:dd:c25:c25a:d00a:d32b
452c19:dd:d9:dd:c25:c25a:d00a:d32c/1282c19:dd:d9:dd:c25:c25a:d00a:d32c
462c19:dd:d9:dd:c25:c25a:d00a:d32d/1282c19:dd:d9:dd:c25:c25a:d00a:d32d
472c19:dd:d9:dd:c25:c25a:d00a:d32e/1282c19:dd:d9:dd:c25:c25a:d00a:d32e
482c19:dd:d9:dd:c25:c25a:d00a:d32f/1282c19:dd:d9:dd:c25:c25a:d00a:d32f
492c19:dd:d9:dd:c25:c25a:d00a:d330/1282c19:dd:d9:dd:c25:c25a:d00a:d330
502c19:dd:d9:dd:c25:c25a:d00a:d331/1282c19:dd:d9:dd:c25:c25a:d00a:d331
512c19:dd:d9:dd:c25:c25a:d00a:d332/1282c19:dd:d9:dd:c25:c25a:d00a:d332
522c19:dd:d9:dd:c25:c25a:d00a:d333/1282c19:dd:d9:dd:c25:c25a:d00a:d333
532c19:dd:d9:dd:c25:c25a:d00a:d334/1282c19:dd:d9:dd:c25:c25a:d00a:d334
542c19:dd:d9:dd:c25:c25a:d00a:d335/1282c19:dd:d9:dd:c25:c25a:d00a:d335
552c19:dd:d9:dd:c25:c25a:d00a:d336/1282c19:dd:d9:dd:c25:c25a:d00a:d336
562c19:dd:d9:dd:c25:c25a:d00a:d337/1282c19:dd:d9:dd:c25:c25a:d00a:d337
572c19:dd:d9:dd:c25:c25a:d00a:d338/1282c19:dd:d9:dd:c25:c25a:d00a:d338
582c19:dd:d9:dd:c25:c25a:d00a:d339/1282c19:dd:d9:dd:c25:c25a:d00a:d339
592c19:dd:d9:dd:c25:c25a:d00a:d33a/1282c19:dd:d9:dd:c25:c25a:d00a:d33a
602c19:dd:d9:dd:c25:c25a:d00a:d33b/1282c19:dd:d9:dd:c25:c25a:d00a:d33b
612c19:dd:d9:dd:c25:c25a:d00a:d33c/1282c19:dd:d9:dd:c25:c25a:d00a:d33c
622c19:dd:d9:dd:c25:c25a:d00a:d33d/1282c19:dd:d9:dd:c25:c25a:d00a:d33d
632c19:dd:d9:dd:c25:c25a:d00a:d33e/1282c19:dd:d9:dd:c25:c25a:d00a:d33e
642c19:dd:d9:dd:c25:c25a:d00a:d33f/1282c19:dd:d9:dd:c25:c25a:d00a:d33f
652c19:dd:d9:dd:c25:c25a:d00a:d340/1282c19:dd:d9:dd:c25:c25a:d00a:d340
662c19:dd:d9:dd:c25:c25a:d00a:d341/1282c19:dd:d9:dd:c25:c25a:d00a:d341
672c19:dd:d9:dd:c25:c25a:d00a:d342/1282c19:dd:d9:dd:c25:c25a:d00a:d342
682c19:dd:d9:dd:c25:c25a:d00a:d343/1282c19:dd:d9:dd:c25:c25a:d00a:d343
692c19:dd:d9:dd:c25:c25a:d00a:d344/1282c19:dd:d9:dd:c25:c25a:d00a:d344
702c19:dd:d9:dd:c25:c25a:d00a:d345/1282c19:dd:d9:dd:c25:c25a:d00a:d345
712c19:dd:d9:dd:c25:c25a:d00a:d346/1282c19:dd:d9:dd:c25:c25a:d00a:d346
722c19:dd:d9:dd:c25:c25a:d00a:d347/1282c19:dd:d9:dd:c25:c25a:d00a:d347
732c19:dd:d9:dd:c25:c25a:d00a:d348/1282c19:dd:d9:dd:c25:c25a:d00a:d348
742c19:dd:d9:dd:c25:c25a:d00a:d349/1282c19:dd:d9:dd:c25:c25a:d00a:d349
752c19:dd:d9:dd:c25:c25a:d00a:d34a/1282c19:dd:d9:dd:c25:c25a:d00a:d34a
762c19:dd:d9:dd:c25:c25a:d00a:d34b/1282c19:dd:d9:dd:c25:c25a:d00a:d34b
772c19:dd:d9:dd:c25:c25a:d00a:d34c/1282c19:dd:d9:dd:c25:c25a:d00a:d34c
782c19:dd:d9:dd:c25:c25a:d00a:d34d/1282c19:dd:d9:dd:c25:c25a:d00a:d34d
792c19:dd:d9:dd:c25:c25a:d00a:d34e/1282c19:dd:d9:dd:c25:c25a:d00a:d34e
802c19:dd:d9:dd:c25:c25a:d00a:d34f/1282c19:dd:d9:dd:c25:c25a:d00a:d34f
812c19:dd:d9:dd:c25:c25a:d00a:d350/1282c19:dd:d9:dd:c25:c25a:d00a:d350
822c19:dd:d9:dd:c25:c25a:d00a:d351/1282c19:dd:d9:dd:c25:c25a:d00a:d351
832c19:dd:d9:dd:c25:c25a:d00a:d352/1282c19:dd:d9:dd:c25:c25a:d00a:d352
842c19:dd:d9:dd:c25:c25a:d00a:d353/1282c19:dd:d9:dd:c25:c25a:d00a:d353
852c19:dd:d9:dd:c25:c25a:d00a:d354/1282c19:dd:d9:dd:c25:c25a:d00a:d354
862c19:dd:d9:dd:c25:c25a:d00a:d355/1282c19:dd:d9:dd:c25:c25a:d00a:d355
872c19:dd:d9:dd:c25:c25a:d00a:d356/1282c19:dd:d9:dd:c25:c25a:d00a:d356
882c19:dd:d9:dd:c25:c25a:d00a:d357/1282c19:dd:d9:dd:c25:c25a:d00a:d357
892c19:dd:d9:dd:c25:c25a:d00a:d358/1282c19:dd:d9:dd:c25:c25a:d00a:d358
902c19:dd:d9:dd:c25:c25a:d00a:d359/1282c19:dd:d9:dd:c25:c25a:d00a:d359
912c19:dd:d9:dd:c25:c25a:d00a:d35a/1282c19:dd:d9:dd:c25:c25a:d00a:d35a
922c19:dd:d9:dd:c25:c25a:d00a:d35b/1282c19:dd:d9:dd:c25:c25a:d00a:d35b
932c19:dd:d9:dd:c25:c25a:d00a:d35c/1282c19:dd:d9:dd:c25:c25a:d00a:d35c
942c19:dd:d9:dd:c25:c25a:d00a:d35d/1282c19:dd:d9:dd:c25:c25a:d00a:d35d
952c19:dd:d9:dd:c25:c25a:d00a:d35e/1282c19:dd:d9:dd:c25:c25a:d00a:d35e
962c19:dd:d9:dd:c25:c25a:d00a:d35f/1282c19:dd:d9:dd:c25:c25a:d00a:d35f
972c19:dd:d9:dd:c25:c25a:d00a:d360/1282c19:dd:d9:dd:c25:c25a:d00a:d360
982c19:dd:d9:dd:c25:c25a:d00a:d361/1282c19:dd:d9:dd:c25:c25a:d00a:d361
992c19:dd:d9:dd:c25:c25a:d00a:d362/1282c19:dd:d9:dd:c25:c25a:d00a:d362
1002c19:dd:d9:dd:c25:c25a:d00a:d363/1282c19:dd:d9:dd:c25:c25a:d00a:d363
1012c19:dd:d9:dd:c25:c25a:d00a:d364/1282c19:dd:d9:dd:c25:c25a:d00a:d364
1022c19:dd:d9:dd:c25:c25a:d00a:d365/1282c19:dd:d9:dd:c25:c25a:d00a:d365
1032c19:dd:d9:dd:c25:c25a:d00a:d366/1282c19:dd:d9:dd:c25:c25a:d00a:d366
1042c19:dd:d9:dd:c25:c25a:d00a:d367/1282c19:dd:d9:dd:c25:c25a:d00a:d367
1052c19:dd:d9:dd:c25:c25a:d00a:d368/1282c19:dd:d9:dd:c25:c25a:d00a:d368
1062c19:dd:d9:dd:c25:c25a:d00a:d369/1282c19:dd:d9:dd:c25:c25a:d00a:d369
1072c19:dd:d9:dd:c25:c25a:d00a:d36a/1282c19:dd:d9:dd:c25:c25a:d00a:d36a
1082c19:dd:d9:dd:c25:c25a:d00a:d36b/1282c19:dd:d9:dd:c25:c25a:d00a:d36b
1092c19:dd:d9:dd:c25:c25a:d00a:d36c/1282c19:dd:d9:dd:c25:c25a:d00a:d36c
1102c19:dd:d9:dd:c25:c25a:d00a:d36d/1282c19:dd:d9:dd:c25:c25a:d00a:d36d
1112c19:dd:d9:dd:c25:c25a:d00a:d36e/1282c19:dd:d9:dd:c25:c25a:d00a:d36e
1122c19:dd:d9:dd:c25:c25a:d00a:d36f/1282c19:dd:d9:dd:c25:c25a:d00a:d36f
1132c19:dd:d9:dd:c25:c25a:d00a:d370/1282c19:dd:d9:dd:c25:c25a:d00a:d370
1142c19:dd:d9:dd:c25:c25a:d00a:d371/1282c19:dd:d9:dd:c25:c25a:d00a:d371
1152c19:dd:d9:dd:c25:c25a:d00a:d372/1282c19:dd:d9:dd:c25:c25a:d00a:d372
1162c19:dd:d9:dd:c25:c25a:d00a:d373/1282c19:dd:d9:dd:c25:c25a:d00a:d373
1172c19:dd:d9:dd:c25:c25a:d00a:d374/1282c19:dd:d9:dd:c25:c25a:d00a:d374
1182c19:dd:d9:dd:c25:c25a:d00a:d375/1282c19:dd:d9:dd:c25:c25a:d00a:d375
1192c19:dd:d9:dd:c25:c25a:d00a:d376/1282c19:dd:d9:dd:c25:c25a:d00a:d376
1202c19:dd:d9:dd:c25:c25a:d00a:d377/1282c19:dd:d9:dd:c25:c25a:d00a:d377
1212c19:dd:d9:dd:c25:c25a:d00a:d378/1282c19:dd:d9:dd:c25:c25a:d00a:d378
1222c19:dd:d9:dd:c25:c25a:d00a:d379/1282c19:dd:d9:dd:c25:c25a:d00a:d379
1232c19:dd:d9:dd:c25:c25a:d00a:d37a/1282c19:dd:d9:dd:c25:c25a:d00a:d37a
1242c19:dd:d9:dd:c25:c25a:d00a:d37b/1282c19:dd:d9:dd:c25:c25a:d00a:d37b
1252c19:dd:d9:dd:c25:c25a:d00a:d37c/1282c19:dd:d9:dd:c25:c25a:d00a:d37c
1262c19:dd:d9:dd:c25:c25a:d00a:d37d/1282c19:dd:d9:dd:c25:c25a:d00a:d37d
1272c19:dd:d9:dd:c25:c25a:d00a:d37e/1282c19:dd:d9:dd:c25:c25a:d00a:d37e
1282c19:dd:d9:dd:c25:c25a:d00a:d37f/1282c19:dd:d9:dd:c25:c25a:d00a:d37f
1292c19:dd:d9:dd:c25:c25a:d00a:d380/1282c19:dd:d9:dd:c25:c25a:d00a:d380
1302c19:dd:d9:dd:c25:c25a:d00a:d381/1282c19:dd:d9:dd:c25:c25a:d00a:d381
1312c19:dd:d9:dd:c25:c25a:d00a:d382/1282c19:dd:d9:dd:c25:c25a:d00a:d382
1322c19:dd:d9:dd:c25:c25a:d00a:d383/1282c19:dd:d9:dd:c25:c25a:d00a:d383
1332c19:dd:d9:dd:c25:c25a:d00a:d384/1282c19:dd:d9:dd:c25:c25a:d00a:d384
1342c19:dd:d9:dd:c25:c25a:d00a:d385/1282c19:dd:d9:dd:c25:c25a:d00a:d385
1352c19:dd:d9:dd:c25:c25a:d00a:d386/1282c19:dd:d9:dd:c25:c25a:d00a:d386
1362c19:dd:d9:dd:c25:c25a:d00a:d387/1282c19:dd:d9:dd:c25:c25a:d00a:d387
1372c19:dd:d9:dd:c25:c25a:d00a:d388/1282c19:dd:d9:dd:c25:c25a:d00a:d388
1382c19:dd:d9:dd:c25:c25a:d00a:d389/1282c19:dd:d9:dd:c25:c25a:d00a:d389
1392c19:dd:d9:dd:c25:c25a:d00a:d38a/1282c19:dd:d9:dd:c25:c25a:d00a:d38a
1402c19:dd:d9:dd:c25:c25a:d00a:d38b/1282c19:dd:d9:dd:c25:c25a:d00a:d38b
1412c19:dd:d9:dd:c25:c25a:d00a:d38c/1282c19:dd:d9:dd:c25:c25a:d00a:d38c
1422c19:dd:d9:dd:c25:c25a:d00a:d38d/1282c19:dd:d9:dd:c25:c25a:d00a:d38d
1432c19:dd:d9:dd:c25:c25a:d00a:d38e/1282c19:dd:d9:dd:c25:c25a:d00a:d38e
1442c19:dd:d9:dd:c25:c25a:d00a:d38f/1282c19:dd:d9:dd:c25:c25a:d00a:d38f
1452c19:dd:d9:dd:c25:c25a:d00a:d390/1282c19:dd:d9:dd:c25:c25a:d00a:d390
1462c19:dd:d9:dd:c25:c25a:d00a:d391/1282c19:dd:d9:dd:c25:c25a:d00a:d391
1472c19:dd:d9:dd:c25:c25a:d00a:d392/1282c19:dd:d9:dd:c25:c25a:d00a:d392
1482c19:dd:d9:dd:c25:c25a:d00a:d393/1282c19:dd:d9:dd:c25:c25a:d00a:d393
1492c19:dd:d9:dd:c25:c25a:d00a:d394/1282c19:dd:d9:dd:c25:c25a:d00a:d394
1502c19:dd:d9:dd:c25:c25a:d00a:d395/1282c19:dd:d9:dd:c25:c25a:d00a:d395
1512c19:dd:d9:dd:c25:c25a:d00a:d396/1282c19:dd:d9:dd:c25:c25a:d00a:d396
1522c19:dd:d9:dd:c25:c25a:d00a:d397/1282c19:dd:d9:dd:c25:c25a:d00a:d397
1532c19:dd:d9:dd:c25:c25a:d00a:d398/1282c19:dd:d9:dd:c25:c25a:d00a:d398
1542c19:dd:d9:dd:c25:c25a:d00a:d399/1282c19:dd:d9:dd:c25:c25a:d00a:d399
1552c19:dd:d9:dd:c25:c25a:d00a:d39a/1282c19:dd:d9:dd:c25:c25a:d00a:d39a
1562c19:dd:d9:dd:c25:c25a:d00a:d39b/1282c19:dd:d9:dd:c25:c25a:d00a:d39b
1572c19:dd:d9:dd:c25:c25a:d00a:d39c/1282c19:dd:d9:dd:c25:c25a:d00a:d39c
1582c19:dd:d9:dd:c25:c25a:d00a:d39d/1282c19:dd:d9:dd:c25:c25a:d00a:d39d
1592c19:dd:d9:dd:c25:c25a:d00a:d39e/1282c19:dd:d9:dd:c25:c25a:d00a:d39e
1602c19:dd:d9:dd:c25:c25a:d00a:d39f/1282c19:dd:d9:dd:c25:c25a:d00a:d39f
1612c19:dd:d9:dd:c25:c25a:d00a:d3a0/1282c19:dd:d9:dd:c25:c25a:d00a:d3a0
1622c19:dd:d9:dd:c25:c25a:d00a:d3a1/1282c19:dd:d9:dd:c25:c25a:d00a:d3a1
1632c19:dd:d9:dd:c25:c25a:d00a:d3a2/1282c19:dd:d9:dd:c25:c25a:d00a:d3a2
1642c19:dd:d9:dd:c25:c25a:d00a:d3a3/1282c19:dd:d9:dd:c25:c25a:d00a:d3a3
1652c19:dd:d9:dd:c25:c25a:d00a:d3a4/1282c19:dd:d9:dd:c25:c25a:d00a:d3a4
1662c19:dd:d9:dd:c25:c25a:d00a:d3a5/1282c19:dd:d9:dd:c25:c25a:d00a:d3a5
1672c19:dd:d9:dd:c25:c25a:d00a:d3a6/1282c19:dd:d9:dd:c25:c25a:d00a:d3a6
1682c19:dd:d9:dd:c25:c25a:d00a:d3a7/1282c19:dd:d9:dd:c25:c25a:d00a:d3a7
1692c19:dd:d9:dd:c25:c25a:d00a:d3a8/1282c19:dd:d9:dd:c25:c25a:d00a:d3a8
1702c19:dd:d9:dd:c25:c25a:d00a:d3a9/1282c19:dd:d9:dd:c25:c25a:d00a:d3a9
1712c19:dd:d9:dd:c25:c25a:d00a:d3aa/1282c19:dd:d9:dd:c25:c25a:d00a:d3aa
1722c19:dd:d9:dd:c25:c25a:d00a:d3ab/1282c19:dd:d9:dd:c25:c25a:d00a:d3ab
1732c19:dd:d9:dd:c25:c25a:d00a:d3ac/1282c19:dd:d9:dd:c25:c25a:d00a:d3ac
1742c19:dd:d9:dd:c25:c25a:d00a:d3ad/1282c19:dd:d9:dd:c25:c25a:d00a:d3ad
1752c19:dd:d9:dd:c25:c25a:d00a:d3ae/1282c19:dd:d9:dd:c25:c25a:d00a:d3ae
1762c19:dd:d9:dd:c25:c25a:d00a:d3af/1282c19:dd:d9:dd:c25:c25a:d00a:d3af
1772c19:dd:d9:dd:c25:c25a:d00a:d3b0/1282c19:dd:d9:dd:c25:c25a:d00a:d3b0
1782c19:dd:d9:dd:c25:c25a:d00a:d3b1/1282c19:dd:d9:dd:c25:c25a:d00a:d3b1
1792c19:dd:d9:dd:c25:c25a:d00a:d3b2/1282c19:dd:d9:dd:c25:c25a:d00a:d3b2
1802c19:dd:d9:dd:c25:c25a:d00a:d3b3/1282c19:dd:d9:dd:c25:c25a:d00a:d3b3
1812c19:dd:d9:dd:c25:c25a:d00a:d3b4/1282c19:dd:d9:dd:c25:c25a:d00a:d3b4
1822c19:dd:d9:dd:c25:c25a:d00a:d3b5/1282c19:dd:d9:dd:c25:c25a:d00a:d3b5
1832c19:dd:d9:dd:c25:c25a:d00a:d3b6/1282c19:dd:d9:dd:c25:c25a:d00a:d3b6
1842c19:dd:d9:dd:c25:c25a:d00a:d3b7/1282c19:dd:d9:dd:c25:c25a:d00a:d3b7
1852c19:dd:d9:dd:c25:c25a:d00a:d3b8/1282c19:dd:d9:dd:c25:c25a:d00a:d3b8
1862c19:dd:d9:dd:c25:c25a:d00a:d3b9/1282c19:dd:d9:dd:c25:c25a:d00a:d3b9
1872c19:dd:d9:dd:c25:c25a:d00a:d3ba/1282c19:dd:d9:dd:c25:c25a:d00a:d3ba
1882c19:dd:d9:dd:c25:c25a:d00a:d3bb/1282c19:dd:d9:dd:c25:c25a:d00a:d3bb
1892c19:dd:d9:dd:c25:c25a:d00a:d3bc/1282c19:dd:d9:dd:c25:c25a:d00a:d3bc
1902c19:dd:d9:dd:c25:c25a:d00a:d3bd/1282c19:dd:d9:dd:c25:c25a:d00a:d3bd
1912c19:dd:d9:dd:c25:c25a:d00a:d3be/1282c19:dd:d9:dd:c25:c25a:d00a:d3be
1922c19:dd:d9:dd:c25:c25a:d00a:d3bf/1282c19:dd:d9:dd:c25:c25a:d00a:d3bf
1932c19:dd:d9:dd:c25:c25a:d00a:d3c0/1282c19:dd:d9:dd:c25:c25a:d00a:d3c0
1942c19:dd:d9:dd:c25:c25a:d00a:d3c1/1282c19:dd:d9:dd:c25:c25a:d00a:d3c1
1952c19:dd:d9:dd:c25:c25a:d00a:d3c2/1282c19:dd:d9:dd:c25:c25a:d00a:d3c2
1962c19:dd:d9:dd:c25:c25a:d00a:d3c3/1282c19:dd:d9:dd:c25:c25a:d00a:d3c3
1972c19:dd:d9:dd:c25:c25a:d00a:d3c4/1282c19:dd:d9:dd:c25:c25a:d00a:d3c4
1982c19:dd:d9:dd:c25:c25a:d00a:d3c5/1282c19:dd:d9:dd:c25:c25a:d00a:d3c5
1992c19:dd:d9:dd:c25:c25a:d00a:d3c6/1282c19:dd:d9:dd:c25:c25a:d00a:d3c6
2002c19:dd:d9:dd:c25:c25a:d00a:d3c7/1282c19:dd:d9:dd:c25:c25a:d00a:d3c7
2012c19:dd:d9:dd:c25:c25a:d00a:d3c8/1282c19:dd:d9:dd:c25:c25a:d00a:d3c8
2022c19:dd:d9:dd:c25:c25a:d00a:d3c9/1282c19:dd:d9:dd:c25:c25a:d00a:d3c9
2032c19:dd:d9:dd:c25:c25a:d00a:d3ca/1282c19:dd:d9:dd:c25:c25a:d00a:d3ca
2042c19:dd:d9:dd:c25:c25a:d00a:d3cb/1282c19:dd:d9:dd:c25:c25a:d00a:d3cb
2052c19:dd:d9:dd:c25:c25a:d00a:d3cc/1282c19:dd:d9:dd:c25:c25a:d00a:d3cc
2062c19:dd:d9:dd:c25:c25a:d00a:d3cd/1282c19:dd:d9:dd:c25:c25a:d00a:d3cd
2072c19:dd:d9:dd:c25:c25a:d00a:d3ce/1282c19:dd:d9:dd:c25:c25a:d00a:d3ce
2082c19:dd:d9:dd:c25:c25a:d00a:d3cf/1282c19:dd:d9:dd:c25:c25a:d00a:d3cf
2092c19:dd:d9:dd:c25:c25a:d00a:d3d0/1282c19:dd:d9:dd:c25:c25a:d00a:d3d0
2102c19:dd:d9:dd:c25:c25a:d00a:d3d1/1282c19:dd:d9:dd:c25:c25a:d00a:d3d1
2112c19:dd:d9:dd:c25:c25a:d00a:d3d2/1282c19:dd:d9:dd:c25:c25a:d00a:d3d2
2122c19:dd:d9:dd:c25:c25a:d00a:d3d3/1282c19:dd:d9:dd:c25:c25a:d00a:d3d3
2132c19:dd:d9:dd:c25:c25a:d00a:d3d4/1282c19:dd:d9:dd:c25:c25a:d00a:d3d4
2142c19:dd:d9:dd:c25:c25a:d00a:d3d5/1282c19:dd:d9:dd:c25:c25a:d00a:d3d5
2152c19:dd:d9:dd:c25:c25a:d00a:d3d6/1282c19:dd:d9:dd:c25:c25a:d00a:d3d6
2162c19:dd:d9:dd:c25:c25a:d00a:d3d7/1282c19:dd:d9:dd:c25:c25a:d00a:d3d7
2172c19:dd:d9:dd:c25:c25a:d00a:d3d8/1282c19:dd:d9:dd:c25:c25a:d00a:d3d8
2182c19:dd:d9:dd:c25:c25a:d00a:d3d9/1282c19:dd:d9:dd:c25:c25a:d00a:d3d9
2192c19:dd:d9:dd:c25:c25a:d00a:d3da/1282c19:dd:d9:dd:c25:c25a:d00a:d3da
2202c19:dd:d9:dd:c25:c25a:d00a:d3db/1282c19:dd:d9:dd:c25:c25a:d00a:d3db
2212c19:dd:d9:dd:c25:c25a:d00a:d3dc/1282c19:dd:d9:dd:c25:c25a:d00a:d3dc
2222c19:dd:d9:dd:c25:c25a:d00a:d3dd/1282c19:dd:d9:dd:c25:c25a:d00a:d3dd
2232c19:dd:d9:dd:c25:c25a:d00a:d3de/1282c19:dd:d9:dd:c25:c25a:d00a:d3de
2242c19:dd:d9:dd:c25:c25a:d00a:d3df/1282c19:dd:d9:dd:c25:c25a:d00a:d3df
2252c19:dd:d9:dd:c25:c25a:d00a:d3e0/1282c19:dd:d9:dd:c25:c25a:d00a:d3e0
2262c19:dd:d9:dd:c25:c25a:d00a:d3e1/1282c19:dd:d9:dd:c25:c25a:d00a:d3e1
2272c19:dd:d9:dd:c25:c25a:d00a:d3e2/1282c19:dd:d9:dd:c25:c25a:d00a:d3e2
2282c19:dd:d9:dd:c25:c25a:d00a:d3e3/1282c19:dd:d9:dd:c25:c25a:d00a:d3e3
2292c19:dd:d9:dd:c25:c25a:d00a:d3e4/1282c19:dd:d9:dd:c25:c25a:d00a:d3e4
2302c19:dd:d9:dd:c25:c25a:d00a:d3e5/1282c19:dd:d9:dd:c25:c25a:d00a:d3e5
2312c19:dd:d9:dd:c25:c25a:d00a:d3e6/1282c19:dd:d9:dd:c25:c25a:d00a:d3e6
2322c19:dd:d9:dd:c25:c25a:d00a:d3e7/1282c19:dd:d9:dd:c25:c25a:d00a:d3e7
2332c19:dd:d9:dd:c25:c25a:d00a:d3e8/1282c19:dd:d9:dd:c25:c25a:d00a:d3e8
2342c19:dd:d9:dd:c25:c25a:d00a:d3e9/1282c19:dd:d9:dd:c25:c25a:d00a:d3e9
2352c19:dd:d9:dd:c25:c25a:d00a:d3ea/1282c19:dd:d9:dd:c25:c25a:d00a:d3ea
2362c19:dd:d9:dd:c25:c25a:d00a:d3eb/1282c19:dd:d9:dd:c25:c25a:d00a:d3eb
2372c19:dd:d9:dd:c25:c25a:d00a:d3ec/1282c19:dd:d9:dd:c25:c25a:d00a:d3ec
2382c19:dd:d9:dd:c25:c25a:d00a:d3ed/1282c19:dd:d9:dd:c25:c25a:d00a:d3ed
2392c19:dd:d9:dd:c25:c25a:d00a:d3ee/1282c19:dd:d9:dd:c25:c25a:d00a:d3ee
2402c19:dd:d9:dd:c25:c25a:d00a:d3ef/1282c19:dd:d9:dd:c25:c25a:d00a:d3ef
2412c19:dd:d9:dd:c25:c25a:d00a:d3f0/1282c19:dd:d9:dd:c25:c25a:d00a:d3f0
2422c19:dd:d9:dd:c25:c25a:d00a:d3f1/1282c19:dd:d9:dd:c25:c25a:d00a:d3f1
2432c19:dd:d9:dd:c25:c25a:d00a:d3f2/1282c19:dd:d9:dd:c25:c25a:d00a:d3f2
2442c19:dd:d9:dd:c25:c25a:d00a:d3f3/1282c19:dd:d9:dd:c25:c25a:d00a:d3f3
2452c19:dd:d9:dd:c25:c25a:d00a:d3f4/1282c19:dd:d9:dd:c25:c25a:d00a:d3f4
2462c19:dd:d9:dd:c25:c25a:d00a:d3f5/1282c19:dd:d9:dd:c25:c25a:d00a:d3f5
2472c19:dd:d9:dd:c25:c25a:d00a:d3f6/1282c19:dd:d9:dd:c25:c25a:d00a:d3f6
2482c19:dd:d9:dd:c25:c25a:d00a:d3f7/1282c19:dd:d9:dd:c25:c25a:d00a:d3f7
2492c19:dd:d9:dd:c25:c25a:d00a:d3f8/1282c19:dd:d9:dd:c25:c25a:d00a:d3f8
2502c19:dd:d9:dd:c25:c25a:d00a:d3f9/1282c19:dd:d9:dd:c25:c25a:d00a:d3f9
2512c19:dd:d9:dd:c25:c25a:d00a:d3fa/1282c19:dd:d9:dd:c25:c25a:d00a:d3fa
2522c19:dd:d9:dd:c25:c25a:d00a:d3fb/1282c19:dd:d9:dd:c25:c25a:d00a:d3fb
2532c19:dd:d9:dd:c25:c25a:d00a:d3fc/1282c19:dd:d9:dd:c25:c25a:d00a:d3fc
2542c19:dd:d9:dd:c25:c25a:d00a:d3fd/1282c19:dd:d9:dd:c25:c25a:d00a:d3fd
2552c19:dd:d9:dd:c25:c25a:d00a:d3fe/1282c19:dd:d9:dd:c25:c25a:d00a:d3fe
2562c19:dd:d9:dd:c25:c25a:d00a:d3ff/1282c19:dd:d9:dd:c25:c25a:d00a:d3ff

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.