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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:c25:94de:f300/120
First address
2c19:dd:d9:dd:c25:c25:94de:f300
Last address
2c19:dd:d9:dd:c25:c25:94de:f3ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:f300
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.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
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:94de:f300/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:f300/1282c19:dd:d9:dd:c25:c25:94de:f300
22c19:dd:d9:dd:c25:c25:94de:f301/1282c19:dd:d9:dd:c25:c25:94de:f301
32c19:dd:d9:dd:c25:c25:94de:f302/1282c19:dd:d9:dd:c25:c25:94de:f302
42c19:dd:d9:dd:c25:c25:94de:f303/1282c19:dd:d9:dd:c25:c25:94de:f303
52c19:dd:d9:dd:c25:c25:94de:f304/1282c19:dd:d9:dd:c25:c25:94de:f304
62c19:dd:d9:dd:c25:c25:94de:f305/1282c19:dd:d9:dd:c25:c25:94de:f305
72c19:dd:d9:dd:c25:c25:94de:f306/1282c19:dd:d9:dd:c25:c25:94de:f306
82c19:dd:d9:dd:c25:c25:94de:f307/1282c19:dd:d9:dd:c25:c25:94de:f307
92c19:dd:d9:dd:c25:c25:94de:f308/1282c19:dd:d9:dd:c25:c25:94de:f308
102c19:dd:d9:dd:c25:c25:94de:f309/1282c19:dd:d9:dd:c25:c25:94de:f309
112c19:dd:d9:dd:c25:c25:94de:f30a/1282c19:dd:d9:dd:c25:c25:94de:f30a
122c19:dd:d9:dd:c25:c25:94de:f30b/1282c19:dd:d9:dd:c25:c25:94de:f30b
132c19:dd:d9:dd:c25:c25:94de:f30c/1282c19:dd:d9:dd:c25:c25:94de:f30c
142c19:dd:d9:dd:c25:c25:94de:f30d/1282c19:dd:d9:dd:c25:c25:94de:f30d
152c19:dd:d9:dd:c25:c25:94de:f30e/1282c19:dd:d9:dd:c25:c25:94de:f30e
162c19:dd:d9:dd:c25:c25:94de:f30f/1282c19:dd:d9:dd:c25:c25:94de:f30f
172c19:dd:d9:dd:c25:c25:94de:f310/1282c19:dd:d9:dd:c25:c25:94de:f310
182c19:dd:d9:dd:c25:c25:94de:f311/1282c19:dd:d9:dd:c25:c25:94de:f311
192c19:dd:d9:dd:c25:c25:94de:f312/1282c19:dd:d9:dd:c25:c25:94de:f312
202c19:dd:d9:dd:c25:c25:94de:f313/1282c19:dd:d9:dd:c25:c25:94de:f313
212c19:dd:d9:dd:c25:c25:94de:f314/1282c19:dd:d9:dd:c25:c25:94de:f314
222c19:dd:d9:dd:c25:c25:94de:f315/1282c19:dd:d9:dd:c25:c25:94de:f315
232c19:dd:d9:dd:c25:c25:94de:f316/1282c19:dd:d9:dd:c25:c25:94de:f316
242c19:dd:d9:dd:c25:c25:94de:f317/1282c19:dd:d9:dd:c25:c25:94de:f317
252c19:dd:d9:dd:c25:c25:94de:f318/1282c19:dd:d9:dd:c25:c25:94de:f318
262c19:dd:d9:dd:c25:c25:94de:f319/1282c19:dd:d9:dd:c25:c25:94de:f319
272c19:dd:d9:dd:c25:c25:94de:f31a/1282c19:dd:d9:dd:c25:c25:94de:f31a
282c19:dd:d9:dd:c25:c25:94de:f31b/1282c19:dd:d9:dd:c25:c25:94de:f31b
292c19:dd:d9:dd:c25:c25:94de:f31c/1282c19:dd:d9:dd:c25:c25:94de:f31c
302c19:dd:d9:dd:c25:c25:94de:f31d/1282c19:dd:d9:dd:c25:c25:94de:f31d
312c19:dd:d9:dd:c25:c25:94de:f31e/1282c19:dd:d9:dd:c25:c25:94de:f31e
322c19:dd:d9:dd:c25:c25:94de:f31f/1282c19:dd:d9:dd:c25:c25:94de:f31f
332c19:dd:d9:dd:c25:c25:94de:f320/1282c19:dd:d9:dd:c25:c25:94de:f320
342c19:dd:d9:dd:c25:c25:94de:f321/1282c19:dd:d9:dd:c25:c25:94de:f321
352c19:dd:d9:dd:c25:c25:94de:f322/1282c19:dd:d9:dd:c25:c25:94de:f322
362c19:dd:d9:dd:c25:c25:94de:f323/1282c19:dd:d9:dd:c25:c25:94de:f323
372c19:dd:d9:dd:c25:c25:94de:f324/1282c19:dd:d9:dd:c25:c25:94de:f324
382c19:dd:d9:dd:c25:c25:94de:f325/1282c19:dd:d9:dd:c25:c25:94de:f325
392c19:dd:d9:dd:c25:c25:94de:f326/1282c19:dd:d9:dd:c25:c25:94de:f326
402c19:dd:d9:dd:c25:c25:94de:f327/1282c19:dd:d9:dd:c25:c25:94de:f327
412c19:dd:d9:dd:c25:c25:94de:f328/1282c19:dd:d9:dd:c25:c25:94de:f328
422c19:dd:d9:dd:c25:c25:94de:f329/1282c19:dd:d9:dd:c25:c25:94de:f329
432c19:dd:d9:dd:c25:c25:94de:f32a/1282c19:dd:d9:dd:c25:c25:94de:f32a
442c19:dd:d9:dd:c25:c25:94de:f32b/1282c19:dd:d9:dd:c25:c25:94de:f32b
452c19:dd:d9:dd:c25:c25:94de:f32c/1282c19:dd:d9:dd:c25:c25:94de:f32c
462c19:dd:d9:dd:c25:c25:94de:f32d/1282c19:dd:d9:dd:c25:c25:94de:f32d
472c19:dd:d9:dd:c25:c25:94de:f32e/1282c19:dd:d9:dd:c25:c25:94de:f32e
482c19:dd:d9:dd:c25:c25:94de:f32f/1282c19:dd:d9:dd:c25:c25:94de:f32f
492c19:dd:d9:dd:c25:c25:94de:f330/1282c19:dd:d9:dd:c25:c25:94de:f330
502c19:dd:d9:dd:c25:c25:94de:f331/1282c19:dd:d9:dd:c25:c25:94de:f331
512c19:dd:d9:dd:c25:c25:94de:f332/1282c19:dd:d9:dd:c25:c25:94de:f332
522c19:dd:d9:dd:c25:c25:94de:f333/1282c19:dd:d9:dd:c25:c25:94de:f333
532c19:dd:d9:dd:c25:c25:94de:f334/1282c19:dd:d9:dd:c25:c25:94de:f334
542c19:dd:d9:dd:c25:c25:94de:f335/1282c19:dd:d9:dd:c25:c25:94de:f335
552c19:dd:d9:dd:c25:c25:94de:f336/1282c19:dd:d9:dd:c25:c25:94de:f336
562c19:dd:d9:dd:c25:c25:94de:f337/1282c19:dd:d9:dd:c25:c25:94de:f337
572c19:dd:d9:dd:c25:c25:94de:f338/1282c19:dd:d9:dd:c25:c25:94de:f338
582c19:dd:d9:dd:c25:c25:94de:f339/1282c19:dd:d9:dd:c25:c25:94de:f339
592c19:dd:d9:dd:c25:c25:94de:f33a/1282c19:dd:d9:dd:c25:c25:94de:f33a
602c19:dd:d9:dd:c25:c25:94de:f33b/1282c19:dd:d9:dd:c25:c25:94de:f33b
612c19:dd:d9:dd:c25:c25:94de:f33c/1282c19:dd:d9:dd:c25:c25:94de:f33c
622c19:dd:d9:dd:c25:c25:94de:f33d/1282c19:dd:d9:dd:c25:c25:94de:f33d
632c19:dd:d9:dd:c25:c25:94de:f33e/1282c19:dd:d9:dd:c25:c25:94de:f33e
642c19:dd:d9:dd:c25:c25:94de:f33f/1282c19:dd:d9:dd:c25:c25:94de:f33f
652c19:dd:d9:dd:c25:c25:94de:f340/1282c19:dd:d9:dd:c25:c25:94de:f340
662c19:dd:d9:dd:c25:c25:94de:f341/1282c19:dd:d9:dd:c25:c25:94de:f341
672c19:dd:d9:dd:c25:c25:94de:f342/1282c19:dd:d9:dd:c25:c25:94de:f342
682c19:dd:d9:dd:c25:c25:94de:f343/1282c19:dd:d9:dd:c25:c25:94de:f343
692c19:dd:d9:dd:c25:c25:94de:f344/1282c19:dd:d9:dd:c25:c25:94de:f344
702c19:dd:d9:dd:c25:c25:94de:f345/1282c19:dd:d9:dd:c25:c25:94de:f345
712c19:dd:d9:dd:c25:c25:94de:f346/1282c19:dd:d9:dd:c25:c25:94de:f346
722c19:dd:d9:dd:c25:c25:94de:f347/1282c19:dd:d9:dd:c25:c25:94de:f347
732c19:dd:d9:dd:c25:c25:94de:f348/1282c19:dd:d9:dd:c25:c25:94de:f348
742c19:dd:d9:dd:c25:c25:94de:f349/1282c19:dd:d9:dd:c25:c25:94de:f349
752c19:dd:d9:dd:c25:c25:94de:f34a/1282c19:dd:d9:dd:c25:c25:94de:f34a
762c19:dd:d9:dd:c25:c25:94de:f34b/1282c19:dd:d9:dd:c25:c25:94de:f34b
772c19:dd:d9:dd:c25:c25:94de:f34c/1282c19:dd:d9:dd:c25:c25:94de:f34c
782c19:dd:d9:dd:c25:c25:94de:f34d/1282c19:dd:d9:dd:c25:c25:94de:f34d
792c19:dd:d9:dd:c25:c25:94de:f34e/1282c19:dd:d9:dd:c25:c25:94de:f34e
802c19:dd:d9:dd:c25:c25:94de:f34f/1282c19:dd:d9:dd:c25:c25:94de:f34f
812c19:dd:d9:dd:c25:c25:94de:f350/1282c19:dd:d9:dd:c25:c25:94de:f350
822c19:dd:d9:dd:c25:c25:94de:f351/1282c19:dd:d9:dd:c25:c25:94de:f351
832c19:dd:d9:dd:c25:c25:94de:f352/1282c19:dd:d9:dd:c25:c25:94de:f352
842c19:dd:d9:dd:c25:c25:94de:f353/1282c19:dd:d9:dd:c25:c25:94de:f353
852c19:dd:d9:dd:c25:c25:94de:f354/1282c19:dd:d9:dd:c25:c25:94de:f354
862c19:dd:d9:dd:c25:c25:94de:f355/1282c19:dd:d9:dd:c25:c25:94de:f355
872c19:dd:d9:dd:c25:c25:94de:f356/1282c19:dd:d9:dd:c25:c25:94de:f356
882c19:dd:d9:dd:c25:c25:94de:f357/1282c19:dd:d9:dd:c25:c25:94de:f357
892c19:dd:d9:dd:c25:c25:94de:f358/1282c19:dd:d9:dd:c25:c25:94de:f358
902c19:dd:d9:dd:c25:c25:94de:f359/1282c19:dd:d9:dd:c25:c25:94de:f359
912c19:dd:d9:dd:c25:c25:94de:f35a/1282c19:dd:d9:dd:c25:c25:94de:f35a
922c19:dd:d9:dd:c25:c25:94de:f35b/1282c19:dd:d9:dd:c25:c25:94de:f35b
932c19:dd:d9:dd:c25:c25:94de:f35c/1282c19:dd:d9:dd:c25:c25:94de:f35c
942c19:dd:d9:dd:c25:c25:94de:f35d/1282c19:dd:d9:dd:c25:c25:94de:f35d
952c19:dd:d9:dd:c25:c25:94de:f35e/1282c19:dd:d9:dd:c25:c25:94de:f35e
962c19:dd:d9:dd:c25:c25:94de:f35f/1282c19:dd:d9:dd:c25:c25:94de:f35f
972c19:dd:d9:dd:c25:c25:94de:f360/1282c19:dd:d9:dd:c25:c25:94de:f360
982c19:dd:d9:dd:c25:c25:94de:f361/1282c19:dd:d9:dd:c25:c25:94de:f361
992c19:dd:d9:dd:c25:c25:94de:f362/1282c19:dd:d9:dd:c25:c25:94de:f362
1002c19:dd:d9:dd:c25:c25:94de:f363/1282c19:dd:d9:dd:c25:c25:94de:f363
1012c19:dd:d9:dd:c25:c25:94de:f364/1282c19:dd:d9:dd:c25:c25:94de:f364
1022c19:dd:d9:dd:c25:c25:94de:f365/1282c19:dd:d9:dd:c25:c25:94de:f365
1032c19:dd:d9:dd:c25:c25:94de:f366/1282c19:dd:d9:dd:c25:c25:94de:f366
1042c19:dd:d9:dd:c25:c25:94de:f367/1282c19:dd:d9:dd:c25:c25:94de:f367
1052c19:dd:d9:dd:c25:c25:94de:f368/1282c19:dd:d9:dd:c25:c25:94de:f368
1062c19:dd:d9:dd:c25:c25:94de:f369/1282c19:dd:d9:dd:c25:c25:94de:f369
1072c19:dd:d9:dd:c25:c25:94de:f36a/1282c19:dd:d9:dd:c25:c25:94de:f36a
1082c19:dd:d9:dd:c25:c25:94de:f36b/1282c19:dd:d9:dd:c25:c25:94de:f36b
1092c19:dd:d9:dd:c25:c25:94de:f36c/1282c19:dd:d9:dd:c25:c25:94de:f36c
1102c19:dd:d9:dd:c25:c25:94de:f36d/1282c19:dd:d9:dd:c25:c25:94de:f36d
1112c19:dd:d9:dd:c25:c25:94de:f36e/1282c19:dd:d9:dd:c25:c25:94de:f36e
1122c19:dd:d9:dd:c25:c25:94de:f36f/1282c19:dd:d9:dd:c25:c25:94de:f36f
1132c19:dd:d9:dd:c25:c25:94de:f370/1282c19:dd:d9:dd:c25:c25:94de:f370
1142c19:dd:d9:dd:c25:c25:94de:f371/1282c19:dd:d9:dd:c25:c25:94de:f371
1152c19:dd:d9:dd:c25:c25:94de:f372/1282c19:dd:d9:dd:c25:c25:94de:f372
1162c19:dd:d9:dd:c25:c25:94de:f373/1282c19:dd:d9:dd:c25:c25:94de:f373
1172c19:dd:d9:dd:c25:c25:94de:f374/1282c19:dd:d9:dd:c25:c25:94de:f374
1182c19:dd:d9:dd:c25:c25:94de:f375/1282c19:dd:d9:dd:c25:c25:94de:f375
1192c19:dd:d9:dd:c25:c25:94de:f376/1282c19:dd:d9:dd:c25:c25:94de:f376
1202c19:dd:d9:dd:c25:c25:94de:f377/1282c19:dd:d9:dd:c25:c25:94de:f377
1212c19:dd:d9:dd:c25:c25:94de:f378/1282c19:dd:d9:dd:c25:c25:94de:f378
1222c19:dd:d9:dd:c25:c25:94de:f379/1282c19:dd:d9:dd:c25:c25:94de:f379
1232c19:dd:d9:dd:c25:c25:94de:f37a/1282c19:dd:d9:dd:c25:c25:94de:f37a
1242c19:dd:d9:dd:c25:c25:94de:f37b/1282c19:dd:d9:dd:c25:c25:94de:f37b
1252c19:dd:d9:dd:c25:c25:94de:f37c/1282c19:dd:d9:dd:c25:c25:94de:f37c
1262c19:dd:d9:dd:c25:c25:94de:f37d/1282c19:dd:d9:dd:c25:c25:94de:f37d
1272c19:dd:d9:dd:c25:c25:94de:f37e/1282c19:dd:d9:dd:c25:c25:94de:f37e
1282c19:dd:d9:dd:c25:c25:94de:f37f/1282c19:dd:d9:dd:c25:c25:94de:f37f
1292c19:dd:d9:dd:c25:c25:94de:f380/1282c19:dd:d9:dd:c25:c25:94de:f380
1302c19:dd:d9:dd:c25:c25:94de:f381/1282c19:dd:d9:dd:c25:c25:94de:f381
1312c19:dd:d9:dd:c25:c25:94de:f382/1282c19:dd:d9:dd:c25:c25:94de:f382
1322c19:dd:d9:dd:c25:c25:94de:f383/1282c19:dd:d9:dd:c25:c25:94de:f383
1332c19:dd:d9:dd:c25:c25:94de:f384/1282c19:dd:d9:dd:c25:c25:94de:f384
1342c19:dd:d9:dd:c25:c25:94de:f385/1282c19:dd:d9:dd:c25:c25:94de:f385
1352c19:dd:d9:dd:c25:c25:94de:f386/1282c19:dd:d9:dd:c25:c25:94de:f386
1362c19:dd:d9:dd:c25:c25:94de:f387/1282c19:dd:d9:dd:c25:c25:94de:f387
1372c19:dd:d9:dd:c25:c25:94de:f388/1282c19:dd:d9:dd:c25:c25:94de:f388
1382c19:dd:d9:dd:c25:c25:94de:f389/1282c19:dd:d9:dd:c25:c25:94de:f389
1392c19:dd:d9:dd:c25:c25:94de:f38a/1282c19:dd:d9:dd:c25:c25:94de:f38a
1402c19:dd:d9:dd:c25:c25:94de:f38b/1282c19:dd:d9:dd:c25:c25:94de:f38b
1412c19:dd:d9:dd:c25:c25:94de:f38c/1282c19:dd:d9:dd:c25:c25:94de:f38c
1422c19:dd:d9:dd:c25:c25:94de:f38d/1282c19:dd:d9:dd:c25:c25:94de:f38d
1432c19:dd:d9:dd:c25:c25:94de:f38e/1282c19:dd:d9:dd:c25:c25:94de:f38e
1442c19:dd:d9:dd:c25:c25:94de:f38f/1282c19:dd:d9:dd:c25:c25:94de:f38f
1452c19:dd:d9:dd:c25:c25:94de:f390/1282c19:dd:d9:dd:c25:c25:94de:f390
1462c19:dd:d9:dd:c25:c25:94de:f391/1282c19:dd:d9:dd:c25:c25:94de:f391
1472c19:dd:d9:dd:c25:c25:94de:f392/1282c19:dd:d9:dd:c25:c25:94de:f392
1482c19:dd:d9:dd:c25:c25:94de:f393/1282c19:dd:d9:dd:c25:c25:94de:f393
1492c19:dd:d9:dd:c25:c25:94de:f394/1282c19:dd:d9:dd:c25:c25:94de:f394
1502c19:dd:d9:dd:c25:c25:94de:f395/1282c19:dd:d9:dd:c25:c25:94de:f395
1512c19:dd:d9:dd:c25:c25:94de:f396/1282c19:dd:d9:dd:c25:c25:94de:f396
1522c19:dd:d9:dd:c25:c25:94de:f397/1282c19:dd:d9:dd:c25:c25:94de:f397
1532c19:dd:d9:dd:c25:c25:94de:f398/1282c19:dd:d9:dd:c25:c25:94de:f398
1542c19:dd:d9:dd:c25:c25:94de:f399/1282c19:dd:d9:dd:c25:c25:94de:f399
1552c19:dd:d9:dd:c25:c25:94de:f39a/1282c19:dd:d9:dd:c25:c25:94de:f39a
1562c19:dd:d9:dd:c25:c25:94de:f39b/1282c19:dd:d9:dd:c25:c25:94de:f39b
1572c19:dd:d9:dd:c25:c25:94de:f39c/1282c19:dd:d9:dd:c25:c25:94de:f39c
1582c19:dd:d9:dd:c25:c25:94de:f39d/1282c19:dd:d9:dd:c25:c25:94de:f39d
1592c19:dd:d9:dd:c25:c25:94de:f39e/1282c19:dd:d9:dd:c25:c25:94de:f39e
1602c19:dd:d9:dd:c25:c25:94de:f39f/1282c19:dd:d9:dd:c25:c25:94de:f39f
1612c19:dd:d9:dd:c25:c25:94de:f3a0/1282c19:dd:d9:dd:c25:c25:94de:f3a0
1622c19:dd:d9:dd:c25:c25:94de:f3a1/1282c19:dd:d9:dd:c25:c25:94de:f3a1
1632c19:dd:d9:dd:c25:c25:94de:f3a2/1282c19:dd:d9:dd:c25:c25:94de:f3a2
1642c19:dd:d9:dd:c25:c25:94de:f3a3/1282c19:dd:d9:dd:c25:c25:94de:f3a3
1652c19:dd:d9:dd:c25:c25:94de:f3a4/1282c19:dd:d9:dd:c25:c25:94de:f3a4
1662c19:dd:d9:dd:c25:c25:94de:f3a5/1282c19:dd:d9:dd:c25:c25:94de:f3a5
1672c19:dd:d9:dd:c25:c25:94de:f3a6/1282c19:dd:d9:dd:c25:c25:94de:f3a6
1682c19:dd:d9:dd:c25:c25:94de:f3a7/1282c19:dd:d9:dd:c25:c25:94de:f3a7
1692c19:dd:d9:dd:c25:c25:94de:f3a8/1282c19:dd:d9:dd:c25:c25:94de:f3a8
1702c19:dd:d9:dd:c25:c25:94de:f3a9/1282c19:dd:d9:dd:c25:c25:94de:f3a9
1712c19:dd:d9:dd:c25:c25:94de:f3aa/1282c19:dd:d9:dd:c25:c25:94de:f3aa
1722c19:dd:d9:dd:c25:c25:94de:f3ab/1282c19:dd:d9:dd:c25:c25:94de:f3ab
1732c19:dd:d9:dd:c25:c25:94de:f3ac/1282c19:dd:d9:dd:c25:c25:94de:f3ac
1742c19:dd:d9:dd:c25:c25:94de:f3ad/1282c19:dd:d9:dd:c25:c25:94de:f3ad
1752c19:dd:d9:dd:c25:c25:94de:f3ae/1282c19:dd:d9:dd:c25:c25:94de:f3ae
1762c19:dd:d9:dd:c25:c25:94de:f3af/1282c19:dd:d9:dd:c25:c25:94de:f3af
1772c19:dd:d9:dd:c25:c25:94de:f3b0/1282c19:dd:d9:dd:c25:c25:94de:f3b0
1782c19:dd:d9:dd:c25:c25:94de:f3b1/1282c19:dd:d9:dd:c25:c25:94de:f3b1
1792c19:dd:d9:dd:c25:c25:94de:f3b2/1282c19:dd:d9:dd:c25:c25:94de:f3b2
1802c19:dd:d9:dd:c25:c25:94de:f3b3/1282c19:dd:d9:dd:c25:c25:94de:f3b3
1812c19:dd:d9:dd:c25:c25:94de:f3b4/1282c19:dd:d9:dd:c25:c25:94de:f3b4
1822c19:dd:d9:dd:c25:c25:94de:f3b5/1282c19:dd:d9:dd:c25:c25:94de:f3b5
1832c19:dd:d9:dd:c25:c25:94de:f3b6/1282c19:dd:d9:dd:c25:c25:94de:f3b6
1842c19:dd:d9:dd:c25:c25:94de:f3b7/1282c19:dd:d9:dd:c25:c25:94de:f3b7
1852c19:dd:d9:dd:c25:c25:94de:f3b8/1282c19:dd:d9:dd:c25:c25:94de:f3b8
1862c19:dd:d9:dd:c25:c25:94de:f3b9/1282c19:dd:d9:dd:c25:c25:94de:f3b9
1872c19:dd:d9:dd:c25:c25:94de:f3ba/1282c19:dd:d9:dd:c25:c25:94de:f3ba
1882c19:dd:d9:dd:c25:c25:94de:f3bb/1282c19:dd:d9:dd:c25:c25:94de:f3bb
1892c19:dd:d9:dd:c25:c25:94de:f3bc/1282c19:dd:d9:dd:c25:c25:94de:f3bc
1902c19:dd:d9:dd:c25:c25:94de:f3bd/1282c19:dd:d9:dd:c25:c25:94de:f3bd
1912c19:dd:d9:dd:c25:c25:94de:f3be/1282c19:dd:d9:dd:c25:c25:94de:f3be
1922c19:dd:d9:dd:c25:c25:94de:f3bf/1282c19:dd:d9:dd:c25:c25:94de:f3bf
1932c19:dd:d9:dd:c25:c25:94de:f3c0/1282c19:dd:d9:dd:c25:c25:94de:f3c0
1942c19:dd:d9:dd:c25:c25:94de:f3c1/1282c19:dd:d9:dd:c25:c25:94de:f3c1
1952c19:dd:d9:dd:c25:c25:94de:f3c2/1282c19:dd:d9:dd:c25:c25:94de:f3c2
1962c19:dd:d9:dd:c25:c25:94de:f3c3/1282c19:dd:d9:dd:c25:c25:94de:f3c3
1972c19:dd:d9:dd:c25:c25:94de:f3c4/1282c19:dd:d9:dd:c25:c25:94de:f3c4
1982c19:dd:d9:dd:c25:c25:94de:f3c5/1282c19:dd:d9:dd:c25:c25:94de:f3c5
1992c19:dd:d9:dd:c25:c25:94de:f3c6/1282c19:dd:d9:dd:c25:c25:94de:f3c6
2002c19:dd:d9:dd:c25:c25:94de:f3c7/1282c19:dd:d9:dd:c25:c25:94de:f3c7
2012c19:dd:d9:dd:c25:c25:94de:f3c8/1282c19:dd:d9:dd:c25:c25:94de:f3c8
2022c19:dd:d9:dd:c25:c25:94de:f3c9/1282c19:dd:d9:dd:c25:c25:94de:f3c9
2032c19:dd:d9:dd:c25:c25:94de:f3ca/1282c19:dd:d9:dd:c25:c25:94de:f3ca
2042c19:dd:d9:dd:c25:c25:94de:f3cb/1282c19:dd:d9:dd:c25:c25:94de:f3cb
2052c19:dd:d9:dd:c25:c25:94de:f3cc/1282c19:dd:d9:dd:c25:c25:94de:f3cc
2062c19:dd:d9:dd:c25:c25:94de:f3cd/1282c19:dd:d9:dd:c25:c25:94de:f3cd
2072c19:dd:d9:dd:c25:c25:94de:f3ce/1282c19:dd:d9:dd:c25:c25:94de:f3ce
2082c19:dd:d9:dd:c25:c25:94de:f3cf/1282c19:dd:d9:dd:c25:c25:94de:f3cf
2092c19:dd:d9:dd:c25:c25:94de:f3d0/1282c19:dd:d9:dd:c25:c25:94de:f3d0
2102c19:dd:d9:dd:c25:c25:94de:f3d1/1282c19:dd:d9:dd:c25:c25:94de:f3d1
2112c19:dd:d9:dd:c25:c25:94de:f3d2/1282c19:dd:d9:dd:c25:c25:94de:f3d2
2122c19:dd:d9:dd:c25:c25:94de:f3d3/1282c19:dd:d9:dd:c25:c25:94de:f3d3
2132c19:dd:d9:dd:c25:c25:94de:f3d4/1282c19:dd:d9:dd:c25:c25:94de:f3d4
2142c19:dd:d9:dd:c25:c25:94de:f3d5/1282c19:dd:d9:dd:c25:c25:94de:f3d5
2152c19:dd:d9:dd:c25:c25:94de:f3d6/1282c19:dd:d9:dd:c25:c25:94de:f3d6
2162c19:dd:d9:dd:c25:c25:94de:f3d7/1282c19:dd:d9:dd:c25:c25:94de:f3d7
2172c19:dd:d9:dd:c25:c25:94de:f3d8/1282c19:dd:d9:dd:c25:c25:94de:f3d8
2182c19:dd:d9:dd:c25:c25:94de:f3d9/1282c19:dd:d9:dd:c25:c25:94de:f3d9
2192c19:dd:d9:dd:c25:c25:94de:f3da/1282c19:dd:d9:dd:c25:c25:94de:f3da
2202c19:dd:d9:dd:c25:c25:94de:f3db/1282c19:dd:d9:dd:c25:c25:94de:f3db
2212c19:dd:d9:dd:c25:c25:94de:f3dc/1282c19:dd:d9:dd:c25:c25:94de:f3dc
2222c19:dd:d9:dd:c25:c25:94de:f3dd/1282c19:dd:d9:dd:c25:c25:94de:f3dd
2232c19:dd:d9:dd:c25:c25:94de:f3de/1282c19:dd:d9:dd:c25:c25:94de:f3de
2242c19:dd:d9:dd:c25:c25:94de:f3df/1282c19:dd:d9:dd:c25:c25:94de:f3df
2252c19:dd:d9:dd:c25:c25:94de:f3e0/1282c19:dd:d9:dd:c25:c25:94de:f3e0
2262c19:dd:d9:dd:c25:c25:94de:f3e1/1282c19:dd:d9:dd:c25:c25:94de:f3e1
2272c19:dd:d9:dd:c25:c25:94de:f3e2/1282c19:dd:d9:dd:c25:c25:94de:f3e2
2282c19:dd:d9:dd:c25:c25:94de:f3e3/1282c19:dd:d9:dd:c25:c25:94de:f3e3
2292c19:dd:d9:dd:c25:c25:94de:f3e4/1282c19:dd:d9:dd:c25:c25:94de:f3e4
2302c19:dd:d9:dd:c25:c25:94de:f3e5/1282c19:dd:d9:dd:c25:c25:94de:f3e5
2312c19:dd:d9:dd:c25:c25:94de:f3e6/1282c19:dd:d9:dd:c25:c25:94de:f3e6
2322c19:dd:d9:dd:c25:c25:94de:f3e7/1282c19:dd:d9:dd:c25:c25:94de:f3e7
2332c19:dd:d9:dd:c25:c25:94de:f3e8/1282c19:dd:d9:dd:c25:c25:94de:f3e8
2342c19:dd:d9:dd:c25:c25:94de:f3e9/1282c19:dd:d9:dd:c25:c25:94de:f3e9
2352c19:dd:d9:dd:c25:c25:94de:f3ea/1282c19:dd:d9:dd:c25:c25:94de:f3ea
2362c19:dd:d9:dd:c25:c25:94de:f3eb/1282c19:dd:d9:dd:c25:c25:94de:f3eb
2372c19:dd:d9:dd:c25:c25:94de:f3ec/1282c19:dd:d9:dd:c25:c25:94de:f3ec
2382c19:dd:d9:dd:c25:c25:94de:f3ed/1282c19:dd:d9:dd:c25:c25:94de:f3ed
2392c19:dd:d9:dd:c25:c25:94de:f3ee/1282c19:dd:d9:dd:c25:c25:94de:f3ee
2402c19:dd:d9:dd:c25:c25:94de:f3ef/1282c19:dd:d9:dd:c25:c25:94de:f3ef
2412c19:dd:d9:dd:c25:c25:94de:f3f0/1282c19:dd:d9:dd:c25:c25:94de:f3f0
2422c19:dd:d9:dd:c25:c25:94de:f3f1/1282c19:dd:d9:dd:c25:c25:94de:f3f1
2432c19:dd:d9:dd:c25:c25:94de:f3f2/1282c19:dd:d9:dd:c25:c25:94de:f3f2
2442c19:dd:d9:dd:c25:c25:94de:f3f3/1282c19:dd:d9:dd:c25:c25:94de:f3f3
2452c19:dd:d9:dd:c25:c25:94de:f3f4/1282c19:dd:d9:dd:c25:c25:94de:f3f4
2462c19:dd:d9:dd:c25:c25:94de:f3f5/1282c19:dd:d9:dd:c25:c25:94de:f3f5
2472c19:dd:d9:dd:c25:c25:94de:f3f6/1282c19:dd:d9:dd:c25:c25:94de:f3f6
2482c19:dd:d9:dd:c25:c25:94de:f3f7/1282c19:dd:d9:dd:c25:c25:94de:f3f7
2492c19:dd:d9:dd:c25:c25:94de:f3f8/1282c19:dd:d9:dd:c25:c25:94de:f3f8
2502c19:dd:d9:dd:c25:c25:94de:f3f9/1282c19:dd:d9:dd:c25:c25:94de:f3f9
2512c19:dd:d9:dd:c25:c25:94de:f3fa/1282c19:dd:d9:dd:c25:c25:94de:f3fa
2522c19:dd:d9:dd:c25:c25:94de:f3fb/1282c19:dd:d9:dd:c25:c25:94de:f3fb
2532c19:dd:d9:dd:c25:c25:94de:f3fc/1282c19:dd:d9:dd:c25:c25:94de:f3fc
2542c19:dd:d9:dd:c25:c25:94de:f3fd/1282c19:dd:d9:dd:c25:c25:94de:f3fd
2552c19:dd:d9:dd:c25:c25:94de:f3fe/1282c19:dd:d9:dd:c25:c25:94de:f3fe
2562c19:dd:d9:dd:c25:c25:94de:f3ff/1282c19:dd:d9:dd:c25:c25:94de:f3ff

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.