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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:b300/120
First address
2c19:dd:d9:dd:c25:c25:94de:b300
Last address
2c19:dd:d9:dd:c25:c25:94de:b3ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:b300
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.b.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:b300/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:b300/1282c19:dd:d9:dd:c25:c25:94de:b300
22c19:dd:d9:dd:c25:c25:94de:b301/1282c19:dd:d9:dd:c25:c25:94de:b301
32c19:dd:d9:dd:c25:c25:94de:b302/1282c19:dd:d9:dd:c25:c25:94de:b302
42c19:dd:d9:dd:c25:c25:94de:b303/1282c19:dd:d9:dd:c25:c25:94de:b303
52c19:dd:d9:dd:c25:c25:94de:b304/1282c19:dd:d9:dd:c25:c25:94de:b304
62c19:dd:d9:dd:c25:c25:94de:b305/1282c19:dd:d9:dd:c25:c25:94de:b305
72c19:dd:d9:dd:c25:c25:94de:b306/1282c19:dd:d9:dd:c25:c25:94de:b306
82c19:dd:d9:dd:c25:c25:94de:b307/1282c19:dd:d9:dd:c25:c25:94de:b307
92c19:dd:d9:dd:c25:c25:94de:b308/1282c19:dd:d9:dd:c25:c25:94de:b308
102c19:dd:d9:dd:c25:c25:94de:b309/1282c19:dd:d9:dd:c25:c25:94de:b309
112c19:dd:d9:dd:c25:c25:94de:b30a/1282c19:dd:d9:dd:c25:c25:94de:b30a
122c19:dd:d9:dd:c25:c25:94de:b30b/1282c19:dd:d9:dd:c25:c25:94de:b30b
132c19:dd:d9:dd:c25:c25:94de:b30c/1282c19:dd:d9:dd:c25:c25:94de:b30c
142c19:dd:d9:dd:c25:c25:94de:b30d/1282c19:dd:d9:dd:c25:c25:94de:b30d
152c19:dd:d9:dd:c25:c25:94de:b30e/1282c19:dd:d9:dd:c25:c25:94de:b30e
162c19:dd:d9:dd:c25:c25:94de:b30f/1282c19:dd:d9:dd:c25:c25:94de:b30f
172c19:dd:d9:dd:c25:c25:94de:b310/1282c19:dd:d9:dd:c25:c25:94de:b310
182c19:dd:d9:dd:c25:c25:94de:b311/1282c19:dd:d9:dd:c25:c25:94de:b311
192c19:dd:d9:dd:c25:c25:94de:b312/1282c19:dd:d9:dd:c25:c25:94de:b312
202c19:dd:d9:dd:c25:c25:94de:b313/1282c19:dd:d9:dd:c25:c25:94de:b313
212c19:dd:d9:dd:c25:c25:94de:b314/1282c19:dd:d9:dd:c25:c25:94de:b314
222c19:dd:d9:dd:c25:c25:94de:b315/1282c19:dd:d9:dd:c25:c25:94de:b315
232c19:dd:d9:dd:c25:c25:94de:b316/1282c19:dd:d9:dd:c25:c25:94de:b316
242c19:dd:d9:dd:c25:c25:94de:b317/1282c19:dd:d9:dd:c25:c25:94de:b317
252c19:dd:d9:dd:c25:c25:94de:b318/1282c19:dd:d9:dd:c25:c25:94de:b318
262c19:dd:d9:dd:c25:c25:94de:b319/1282c19:dd:d9:dd:c25:c25:94de:b319
272c19:dd:d9:dd:c25:c25:94de:b31a/1282c19:dd:d9:dd:c25:c25:94de:b31a
282c19:dd:d9:dd:c25:c25:94de:b31b/1282c19:dd:d9:dd:c25:c25:94de:b31b
292c19:dd:d9:dd:c25:c25:94de:b31c/1282c19:dd:d9:dd:c25:c25:94de:b31c
302c19:dd:d9:dd:c25:c25:94de:b31d/1282c19:dd:d9:dd:c25:c25:94de:b31d
312c19:dd:d9:dd:c25:c25:94de:b31e/1282c19:dd:d9:dd:c25:c25:94de:b31e
322c19:dd:d9:dd:c25:c25:94de:b31f/1282c19:dd:d9:dd:c25:c25:94de:b31f
332c19:dd:d9:dd:c25:c25:94de:b320/1282c19:dd:d9:dd:c25:c25:94de:b320
342c19:dd:d9:dd:c25:c25:94de:b321/1282c19:dd:d9:dd:c25:c25:94de:b321
352c19:dd:d9:dd:c25:c25:94de:b322/1282c19:dd:d9:dd:c25:c25:94de:b322
362c19:dd:d9:dd:c25:c25:94de:b323/1282c19:dd:d9:dd:c25:c25:94de:b323
372c19:dd:d9:dd:c25:c25:94de:b324/1282c19:dd:d9:dd:c25:c25:94de:b324
382c19:dd:d9:dd:c25:c25:94de:b325/1282c19:dd:d9:dd:c25:c25:94de:b325
392c19:dd:d9:dd:c25:c25:94de:b326/1282c19:dd:d9:dd:c25:c25:94de:b326
402c19:dd:d9:dd:c25:c25:94de:b327/1282c19:dd:d9:dd:c25:c25:94de:b327
412c19:dd:d9:dd:c25:c25:94de:b328/1282c19:dd:d9:dd:c25:c25:94de:b328
422c19:dd:d9:dd:c25:c25:94de:b329/1282c19:dd:d9:dd:c25:c25:94de:b329
432c19:dd:d9:dd:c25:c25:94de:b32a/1282c19:dd:d9:dd:c25:c25:94de:b32a
442c19:dd:d9:dd:c25:c25:94de:b32b/1282c19:dd:d9:dd:c25:c25:94de:b32b
452c19:dd:d9:dd:c25:c25:94de:b32c/1282c19:dd:d9:dd:c25:c25:94de:b32c
462c19:dd:d9:dd:c25:c25:94de:b32d/1282c19:dd:d9:dd:c25:c25:94de:b32d
472c19:dd:d9:dd:c25:c25:94de:b32e/1282c19:dd:d9:dd:c25:c25:94de:b32e
482c19:dd:d9:dd:c25:c25:94de:b32f/1282c19:dd:d9:dd:c25:c25:94de:b32f
492c19:dd:d9:dd:c25:c25:94de:b330/1282c19:dd:d9:dd:c25:c25:94de:b330
502c19:dd:d9:dd:c25:c25:94de:b331/1282c19:dd:d9:dd:c25:c25:94de:b331
512c19:dd:d9:dd:c25:c25:94de:b332/1282c19:dd:d9:dd:c25:c25:94de:b332
522c19:dd:d9:dd:c25:c25:94de:b333/1282c19:dd:d9:dd:c25:c25:94de:b333
532c19:dd:d9:dd:c25:c25:94de:b334/1282c19:dd:d9:dd:c25:c25:94de:b334
542c19:dd:d9:dd:c25:c25:94de:b335/1282c19:dd:d9:dd:c25:c25:94de:b335
552c19:dd:d9:dd:c25:c25:94de:b336/1282c19:dd:d9:dd:c25:c25:94de:b336
562c19:dd:d9:dd:c25:c25:94de:b337/1282c19:dd:d9:dd:c25:c25:94de:b337
572c19:dd:d9:dd:c25:c25:94de:b338/1282c19:dd:d9:dd:c25:c25:94de:b338
582c19:dd:d9:dd:c25:c25:94de:b339/1282c19:dd:d9:dd:c25:c25:94de:b339
592c19:dd:d9:dd:c25:c25:94de:b33a/1282c19:dd:d9:dd:c25:c25:94de:b33a
602c19:dd:d9:dd:c25:c25:94de:b33b/1282c19:dd:d9:dd:c25:c25:94de:b33b
612c19:dd:d9:dd:c25:c25:94de:b33c/1282c19:dd:d9:dd:c25:c25:94de:b33c
622c19:dd:d9:dd:c25:c25:94de:b33d/1282c19:dd:d9:dd:c25:c25:94de:b33d
632c19:dd:d9:dd:c25:c25:94de:b33e/1282c19:dd:d9:dd:c25:c25:94de:b33e
642c19:dd:d9:dd:c25:c25:94de:b33f/1282c19:dd:d9:dd:c25:c25:94de:b33f
652c19:dd:d9:dd:c25:c25:94de:b340/1282c19:dd:d9:dd:c25:c25:94de:b340
662c19:dd:d9:dd:c25:c25:94de:b341/1282c19:dd:d9:dd:c25:c25:94de:b341
672c19:dd:d9:dd:c25:c25:94de:b342/1282c19:dd:d9:dd:c25:c25:94de:b342
682c19:dd:d9:dd:c25:c25:94de:b343/1282c19:dd:d9:dd:c25:c25:94de:b343
692c19:dd:d9:dd:c25:c25:94de:b344/1282c19:dd:d9:dd:c25:c25:94de:b344
702c19:dd:d9:dd:c25:c25:94de:b345/1282c19:dd:d9:dd:c25:c25:94de:b345
712c19:dd:d9:dd:c25:c25:94de:b346/1282c19:dd:d9:dd:c25:c25:94de:b346
722c19:dd:d9:dd:c25:c25:94de:b347/1282c19:dd:d9:dd:c25:c25:94de:b347
732c19:dd:d9:dd:c25:c25:94de:b348/1282c19:dd:d9:dd:c25:c25:94de:b348
742c19:dd:d9:dd:c25:c25:94de:b349/1282c19:dd:d9:dd:c25:c25:94de:b349
752c19:dd:d9:dd:c25:c25:94de:b34a/1282c19:dd:d9:dd:c25:c25:94de:b34a
762c19:dd:d9:dd:c25:c25:94de:b34b/1282c19:dd:d9:dd:c25:c25:94de:b34b
772c19:dd:d9:dd:c25:c25:94de:b34c/1282c19:dd:d9:dd:c25:c25:94de:b34c
782c19:dd:d9:dd:c25:c25:94de:b34d/1282c19:dd:d9:dd:c25:c25:94de:b34d
792c19:dd:d9:dd:c25:c25:94de:b34e/1282c19:dd:d9:dd:c25:c25:94de:b34e
802c19:dd:d9:dd:c25:c25:94de:b34f/1282c19:dd:d9:dd:c25:c25:94de:b34f
812c19:dd:d9:dd:c25:c25:94de:b350/1282c19:dd:d9:dd:c25:c25:94de:b350
822c19:dd:d9:dd:c25:c25:94de:b351/1282c19:dd:d9:dd:c25:c25:94de:b351
832c19:dd:d9:dd:c25:c25:94de:b352/1282c19:dd:d9:dd:c25:c25:94de:b352
842c19:dd:d9:dd:c25:c25:94de:b353/1282c19:dd:d9:dd:c25:c25:94de:b353
852c19:dd:d9:dd:c25:c25:94de:b354/1282c19:dd:d9:dd:c25:c25:94de:b354
862c19:dd:d9:dd:c25:c25:94de:b355/1282c19:dd:d9:dd:c25:c25:94de:b355
872c19:dd:d9:dd:c25:c25:94de:b356/1282c19:dd:d9:dd:c25:c25:94de:b356
882c19:dd:d9:dd:c25:c25:94de:b357/1282c19:dd:d9:dd:c25:c25:94de:b357
892c19:dd:d9:dd:c25:c25:94de:b358/1282c19:dd:d9:dd:c25:c25:94de:b358
902c19:dd:d9:dd:c25:c25:94de:b359/1282c19:dd:d9:dd:c25:c25:94de:b359
912c19:dd:d9:dd:c25:c25:94de:b35a/1282c19:dd:d9:dd:c25:c25:94de:b35a
922c19:dd:d9:dd:c25:c25:94de:b35b/1282c19:dd:d9:dd:c25:c25:94de:b35b
932c19:dd:d9:dd:c25:c25:94de:b35c/1282c19:dd:d9:dd:c25:c25:94de:b35c
942c19:dd:d9:dd:c25:c25:94de:b35d/1282c19:dd:d9:dd:c25:c25:94de:b35d
952c19:dd:d9:dd:c25:c25:94de:b35e/1282c19:dd:d9:dd:c25:c25:94de:b35e
962c19:dd:d9:dd:c25:c25:94de:b35f/1282c19:dd:d9:dd:c25:c25:94de:b35f
972c19:dd:d9:dd:c25:c25:94de:b360/1282c19:dd:d9:dd:c25:c25:94de:b360
982c19:dd:d9:dd:c25:c25:94de:b361/1282c19:dd:d9:dd:c25:c25:94de:b361
992c19:dd:d9:dd:c25:c25:94de:b362/1282c19:dd:d9:dd:c25:c25:94de:b362
1002c19:dd:d9:dd:c25:c25:94de:b363/1282c19:dd:d9:dd:c25:c25:94de:b363
1012c19:dd:d9:dd:c25:c25:94de:b364/1282c19:dd:d9:dd:c25:c25:94de:b364
1022c19:dd:d9:dd:c25:c25:94de:b365/1282c19:dd:d9:dd:c25:c25:94de:b365
1032c19:dd:d9:dd:c25:c25:94de:b366/1282c19:dd:d9:dd:c25:c25:94de:b366
1042c19:dd:d9:dd:c25:c25:94de:b367/1282c19:dd:d9:dd:c25:c25:94de:b367
1052c19:dd:d9:dd:c25:c25:94de:b368/1282c19:dd:d9:dd:c25:c25:94de:b368
1062c19:dd:d9:dd:c25:c25:94de:b369/1282c19:dd:d9:dd:c25:c25:94de:b369
1072c19:dd:d9:dd:c25:c25:94de:b36a/1282c19:dd:d9:dd:c25:c25:94de:b36a
1082c19:dd:d9:dd:c25:c25:94de:b36b/1282c19:dd:d9:dd:c25:c25:94de:b36b
1092c19:dd:d9:dd:c25:c25:94de:b36c/1282c19:dd:d9:dd:c25:c25:94de:b36c
1102c19:dd:d9:dd:c25:c25:94de:b36d/1282c19:dd:d9:dd:c25:c25:94de:b36d
1112c19:dd:d9:dd:c25:c25:94de:b36e/1282c19:dd:d9:dd:c25:c25:94de:b36e
1122c19:dd:d9:dd:c25:c25:94de:b36f/1282c19:dd:d9:dd:c25:c25:94de:b36f
1132c19:dd:d9:dd:c25:c25:94de:b370/1282c19:dd:d9:dd:c25:c25:94de:b370
1142c19:dd:d9:dd:c25:c25:94de:b371/1282c19:dd:d9:dd:c25:c25:94de:b371
1152c19:dd:d9:dd:c25:c25:94de:b372/1282c19:dd:d9:dd:c25:c25:94de:b372
1162c19:dd:d9:dd:c25:c25:94de:b373/1282c19:dd:d9:dd:c25:c25:94de:b373
1172c19:dd:d9:dd:c25:c25:94de:b374/1282c19:dd:d9:dd:c25:c25:94de:b374
1182c19:dd:d9:dd:c25:c25:94de:b375/1282c19:dd:d9:dd:c25:c25:94de:b375
1192c19:dd:d9:dd:c25:c25:94de:b376/1282c19:dd:d9:dd:c25:c25:94de:b376
1202c19:dd:d9:dd:c25:c25:94de:b377/1282c19:dd:d9:dd:c25:c25:94de:b377
1212c19:dd:d9:dd:c25:c25:94de:b378/1282c19:dd:d9:dd:c25:c25:94de:b378
1222c19:dd:d9:dd:c25:c25:94de:b379/1282c19:dd:d9:dd:c25:c25:94de:b379
1232c19:dd:d9:dd:c25:c25:94de:b37a/1282c19:dd:d9:dd:c25:c25:94de:b37a
1242c19:dd:d9:dd:c25:c25:94de:b37b/1282c19:dd:d9:dd:c25:c25:94de:b37b
1252c19:dd:d9:dd:c25:c25:94de:b37c/1282c19:dd:d9:dd:c25:c25:94de:b37c
1262c19:dd:d9:dd:c25:c25:94de:b37d/1282c19:dd:d9:dd:c25:c25:94de:b37d
1272c19:dd:d9:dd:c25:c25:94de:b37e/1282c19:dd:d9:dd:c25:c25:94de:b37e
1282c19:dd:d9:dd:c25:c25:94de:b37f/1282c19:dd:d9:dd:c25:c25:94de:b37f
1292c19:dd:d9:dd:c25:c25:94de:b380/1282c19:dd:d9:dd:c25:c25:94de:b380
1302c19:dd:d9:dd:c25:c25:94de:b381/1282c19:dd:d9:dd:c25:c25:94de:b381
1312c19:dd:d9:dd:c25:c25:94de:b382/1282c19:dd:d9:dd:c25:c25:94de:b382
1322c19:dd:d9:dd:c25:c25:94de:b383/1282c19:dd:d9:dd:c25:c25:94de:b383
1332c19:dd:d9:dd:c25:c25:94de:b384/1282c19:dd:d9:dd:c25:c25:94de:b384
1342c19:dd:d9:dd:c25:c25:94de:b385/1282c19:dd:d9:dd:c25:c25:94de:b385
1352c19:dd:d9:dd:c25:c25:94de:b386/1282c19:dd:d9:dd:c25:c25:94de:b386
1362c19:dd:d9:dd:c25:c25:94de:b387/1282c19:dd:d9:dd:c25:c25:94de:b387
1372c19:dd:d9:dd:c25:c25:94de:b388/1282c19:dd:d9:dd:c25:c25:94de:b388
1382c19:dd:d9:dd:c25:c25:94de:b389/1282c19:dd:d9:dd:c25:c25:94de:b389
1392c19:dd:d9:dd:c25:c25:94de:b38a/1282c19:dd:d9:dd:c25:c25:94de:b38a
1402c19:dd:d9:dd:c25:c25:94de:b38b/1282c19:dd:d9:dd:c25:c25:94de:b38b
1412c19:dd:d9:dd:c25:c25:94de:b38c/1282c19:dd:d9:dd:c25:c25:94de:b38c
1422c19:dd:d9:dd:c25:c25:94de:b38d/1282c19:dd:d9:dd:c25:c25:94de:b38d
1432c19:dd:d9:dd:c25:c25:94de:b38e/1282c19:dd:d9:dd:c25:c25:94de:b38e
1442c19:dd:d9:dd:c25:c25:94de:b38f/1282c19:dd:d9:dd:c25:c25:94de:b38f
1452c19:dd:d9:dd:c25:c25:94de:b390/1282c19:dd:d9:dd:c25:c25:94de:b390
1462c19:dd:d9:dd:c25:c25:94de:b391/1282c19:dd:d9:dd:c25:c25:94de:b391
1472c19:dd:d9:dd:c25:c25:94de:b392/1282c19:dd:d9:dd:c25:c25:94de:b392
1482c19:dd:d9:dd:c25:c25:94de:b393/1282c19:dd:d9:dd:c25:c25:94de:b393
1492c19:dd:d9:dd:c25:c25:94de:b394/1282c19:dd:d9:dd:c25:c25:94de:b394
1502c19:dd:d9:dd:c25:c25:94de:b395/1282c19:dd:d9:dd:c25:c25:94de:b395
1512c19:dd:d9:dd:c25:c25:94de:b396/1282c19:dd:d9:dd:c25:c25:94de:b396
1522c19:dd:d9:dd:c25:c25:94de:b397/1282c19:dd:d9:dd:c25:c25:94de:b397
1532c19:dd:d9:dd:c25:c25:94de:b398/1282c19:dd:d9:dd:c25:c25:94de:b398
1542c19:dd:d9:dd:c25:c25:94de:b399/1282c19:dd:d9:dd:c25:c25:94de:b399
1552c19:dd:d9:dd:c25:c25:94de:b39a/1282c19:dd:d9:dd:c25:c25:94de:b39a
1562c19:dd:d9:dd:c25:c25:94de:b39b/1282c19:dd:d9:dd:c25:c25:94de:b39b
1572c19:dd:d9:dd:c25:c25:94de:b39c/1282c19:dd:d9:dd:c25:c25:94de:b39c
1582c19:dd:d9:dd:c25:c25:94de:b39d/1282c19:dd:d9:dd:c25:c25:94de:b39d
1592c19:dd:d9:dd:c25:c25:94de:b39e/1282c19:dd:d9:dd:c25:c25:94de:b39e
1602c19:dd:d9:dd:c25:c25:94de:b39f/1282c19:dd:d9:dd:c25:c25:94de:b39f
1612c19:dd:d9:dd:c25:c25:94de:b3a0/1282c19:dd:d9:dd:c25:c25:94de:b3a0
1622c19:dd:d9:dd:c25:c25:94de:b3a1/1282c19:dd:d9:dd:c25:c25:94de:b3a1
1632c19:dd:d9:dd:c25:c25:94de:b3a2/1282c19:dd:d9:dd:c25:c25:94de:b3a2
1642c19:dd:d9:dd:c25:c25:94de:b3a3/1282c19:dd:d9:dd:c25:c25:94de:b3a3
1652c19:dd:d9:dd:c25:c25:94de:b3a4/1282c19:dd:d9:dd:c25:c25:94de:b3a4
1662c19:dd:d9:dd:c25:c25:94de:b3a5/1282c19:dd:d9:dd:c25:c25:94de:b3a5
1672c19:dd:d9:dd:c25:c25:94de:b3a6/1282c19:dd:d9:dd:c25:c25:94de:b3a6
1682c19:dd:d9:dd:c25:c25:94de:b3a7/1282c19:dd:d9:dd:c25:c25:94de:b3a7
1692c19:dd:d9:dd:c25:c25:94de:b3a8/1282c19:dd:d9:dd:c25:c25:94de:b3a8
1702c19:dd:d9:dd:c25:c25:94de:b3a9/1282c19:dd:d9:dd:c25:c25:94de:b3a9
1712c19:dd:d9:dd:c25:c25:94de:b3aa/1282c19:dd:d9:dd:c25:c25:94de:b3aa
1722c19:dd:d9:dd:c25:c25:94de:b3ab/1282c19:dd:d9:dd:c25:c25:94de:b3ab
1732c19:dd:d9:dd:c25:c25:94de:b3ac/1282c19:dd:d9:dd:c25:c25:94de:b3ac
1742c19:dd:d9:dd:c25:c25:94de:b3ad/1282c19:dd:d9:dd:c25:c25:94de:b3ad
1752c19:dd:d9:dd:c25:c25:94de:b3ae/1282c19:dd:d9:dd:c25:c25:94de:b3ae
1762c19:dd:d9:dd:c25:c25:94de:b3af/1282c19:dd:d9:dd:c25:c25:94de:b3af
1772c19:dd:d9:dd:c25:c25:94de:b3b0/1282c19:dd:d9:dd:c25:c25:94de:b3b0
1782c19:dd:d9:dd:c25:c25:94de:b3b1/1282c19:dd:d9:dd:c25:c25:94de:b3b1
1792c19:dd:d9:dd:c25:c25:94de:b3b2/1282c19:dd:d9:dd:c25:c25:94de:b3b2
1802c19:dd:d9:dd:c25:c25:94de:b3b3/1282c19:dd:d9:dd:c25:c25:94de:b3b3
1812c19:dd:d9:dd:c25:c25:94de:b3b4/1282c19:dd:d9:dd:c25:c25:94de:b3b4
1822c19:dd:d9:dd:c25:c25:94de:b3b5/1282c19:dd:d9:dd:c25:c25:94de:b3b5
1832c19:dd:d9:dd:c25:c25:94de:b3b6/1282c19:dd:d9:dd:c25:c25:94de:b3b6
1842c19:dd:d9:dd:c25:c25:94de:b3b7/1282c19:dd:d9:dd:c25:c25:94de:b3b7
1852c19:dd:d9:dd:c25:c25:94de:b3b8/1282c19:dd:d9:dd:c25:c25:94de:b3b8
1862c19:dd:d9:dd:c25:c25:94de:b3b9/1282c19:dd:d9:dd:c25:c25:94de:b3b9
1872c19:dd:d9:dd:c25:c25:94de:b3ba/1282c19:dd:d9:dd:c25:c25:94de:b3ba
1882c19:dd:d9:dd:c25:c25:94de:b3bb/1282c19:dd:d9:dd:c25:c25:94de:b3bb
1892c19:dd:d9:dd:c25:c25:94de:b3bc/1282c19:dd:d9:dd:c25:c25:94de:b3bc
1902c19:dd:d9:dd:c25:c25:94de:b3bd/1282c19:dd:d9:dd:c25:c25:94de:b3bd
1912c19:dd:d9:dd:c25:c25:94de:b3be/1282c19:dd:d9:dd:c25:c25:94de:b3be
1922c19:dd:d9:dd:c25:c25:94de:b3bf/1282c19:dd:d9:dd:c25:c25:94de:b3bf
1932c19:dd:d9:dd:c25:c25:94de:b3c0/1282c19:dd:d9:dd:c25:c25:94de:b3c0
1942c19:dd:d9:dd:c25:c25:94de:b3c1/1282c19:dd:d9:dd:c25:c25:94de:b3c1
1952c19:dd:d9:dd:c25:c25:94de:b3c2/1282c19:dd:d9:dd:c25:c25:94de:b3c2
1962c19:dd:d9:dd:c25:c25:94de:b3c3/1282c19:dd:d9:dd:c25:c25:94de:b3c3
1972c19:dd:d9:dd:c25:c25:94de:b3c4/1282c19:dd:d9:dd:c25:c25:94de:b3c4
1982c19:dd:d9:dd:c25:c25:94de:b3c5/1282c19:dd:d9:dd:c25:c25:94de:b3c5
1992c19:dd:d9:dd:c25:c25:94de:b3c6/1282c19:dd:d9:dd:c25:c25:94de:b3c6
2002c19:dd:d9:dd:c25:c25:94de:b3c7/1282c19:dd:d9:dd:c25:c25:94de:b3c7
2012c19:dd:d9:dd:c25:c25:94de:b3c8/1282c19:dd:d9:dd:c25:c25:94de:b3c8
2022c19:dd:d9:dd:c25:c25:94de:b3c9/1282c19:dd:d9:dd:c25:c25:94de:b3c9
2032c19:dd:d9:dd:c25:c25:94de:b3ca/1282c19:dd:d9:dd:c25:c25:94de:b3ca
2042c19:dd:d9:dd:c25:c25:94de:b3cb/1282c19:dd:d9:dd:c25:c25:94de:b3cb
2052c19:dd:d9:dd:c25:c25:94de:b3cc/1282c19:dd:d9:dd:c25:c25:94de:b3cc
2062c19:dd:d9:dd:c25:c25:94de:b3cd/1282c19:dd:d9:dd:c25:c25:94de:b3cd
2072c19:dd:d9:dd:c25:c25:94de:b3ce/1282c19:dd:d9:dd:c25:c25:94de:b3ce
2082c19:dd:d9:dd:c25:c25:94de:b3cf/1282c19:dd:d9:dd:c25:c25:94de:b3cf
2092c19:dd:d9:dd:c25:c25:94de:b3d0/1282c19:dd:d9:dd:c25:c25:94de:b3d0
2102c19:dd:d9:dd:c25:c25:94de:b3d1/1282c19:dd:d9:dd:c25:c25:94de:b3d1
2112c19:dd:d9:dd:c25:c25:94de:b3d2/1282c19:dd:d9:dd:c25:c25:94de:b3d2
2122c19:dd:d9:dd:c25:c25:94de:b3d3/1282c19:dd:d9:dd:c25:c25:94de:b3d3
2132c19:dd:d9:dd:c25:c25:94de:b3d4/1282c19:dd:d9:dd:c25:c25:94de:b3d4
2142c19:dd:d9:dd:c25:c25:94de:b3d5/1282c19:dd:d9:dd:c25:c25:94de:b3d5
2152c19:dd:d9:dd:c25:c25:94de:b3d6/1282c19:dd:d9:dd:c25:c25:94de:b3d6
2162c19:dd:d9:dd:c25:c25:94de:b3d7/1282c19:dd:d9:dd:c25:c25:94de:b3d7
2172c19:dd:d9:dd:c25:c25:94de:b3d8/1282c19:dd:d9:dd:c25:c25:94de:b3d8
2182c19:dd:d9:dd:c25:c25:94de:b3d9/1282c19:dd:d9:dd:c25:c25:94de:b3d9
2192c19:dd:d9:dd:c25:c25:94de:b3da/1282c19:dd:d9:dd:c25:c25:94de:b3da
2202c19:dd:d9:dd:c25:c25:94de:b3db/1282c19:dd:d9:dd:c25:c25:94de:b3db
2212c19:dd:d9:dd:c25:c25:94de:b3dc/1282c19:dd:d9:dd:c25:c25:94de:b3dc
2222c19:dd:d9:dd:c25:c25:94de:b3dd/1282c19:dd:d9:dd:c25:c25:94de:b3dd
2232c19:dd:d9:dd:c25:c25:94de:b3de/1282c19:dd:d9:dd:c25:c25:94de:b3de
2242c19:dd:d9:dd:c25:c25:94de:b3df/1282c19:dd:d9:dd:c25:c25:94de:b3df
2252c19:dd:d9:dd:c25:c25:94de:b3e0/1282c19:dd:d9:dd:c25:c25:94de:b3e0
2262c19:dd:d9:dd:c25:c25:94de:b3e1/1282c19:dd:d9:dd:c25:c25:94de:b3e1
2272c19:dd:d9:dd:c25:c25:94de:b3e2/1282c19:dd:d9:dd:c25:c25:94de:b3e2
2282c19:dd:d9:dd:c25:c25:94de:b3e3/1282c19:dd:d9:dd:c25:c25:94de:b3e3
2292c19:dd:d9:dd:c25:c25:94de:b3e4/1282c19:dd:d9:dd:c25:c25:94de:b3e4
2302c19:dd:d9:dd:c25:c25:94de:b3e5/1282c19:dd:d9:dd:c25:c25:94de:b3e5
2312c19:dd:d9:dd:c25:c25:94de:b3e6/1282c19:dd:d9:dd:c25:c25:94de:b3e6
2322c19:dd:d9:dd:c25:c25:94de:b3e7/1282c19:dd:d9:dd:c25:c25:94de:b3e7
2332c19:dd:d9:dd:c25:c25:94de:b3e8/1282c19:dd:d9:dd:c25:c25:94de:b3e8
2342c19:dd:d9:dd:c25:c25:94de:b3e9/1282c19:dd:d9:dd:c25:c25:94de:b3e9
2352c19:dd:d9:dd:c25:c25:94de:b3ea/1282c19:dd:d9:dd:c25:c25:94de:b3ea
2362c19:dd:d9:dd:c25:c25:94de:b3eb/1282c19:dd:d9:dd:c25:c25:94de:b3eb
2372c19:dd:d9:dd:c25:c25:94de:b3ec/1282c19:dd:d9:dd:c25:c25:94de:b3ec
2382c19:dd:d9:dd:c25:c25:94de:b3ed/1282c19:dd:d9:dd:c25:c25:94de:b3ed
2392c19:dd:d9:dd:c25:c25:94de:b3ee/1282c19:dd:d9:dd:c25:c25:94de:b3ee
2402c19:dd:d9:dd:c25:c25:94de:b3ef/1282c19:dd:d9:dd:c25:c25:94de:b3ef
2412c19:dd:d9:dd:c25:c25:94de:b3f0/1282c19:dd:d9:dd:c25:c25:94de:b3f0
2422c19:dd:d9:dd:c25:c25:94de:b3f1/1282c19:dd:d9:dd:c25:c25:94de:b3f1
2432c19:dd:d9:dd:c25:c25:94de:b3f2/1282c19:dd:d9:dd:c25:c25:94de:b3f2
2442c19:dd:d9:dd:c25:c25:94de:b3f3/1282c19:dd:d9:dd:c25:c25:94de:b3f3
2452c19:dd:d9:dd:c25:c25:94de:b3f4/1282c19:dd:d9:dd:c25:c25:94de:b3f4
2462c19:dd:d9:dd:c25:c25:94de:b3f5/1282c19:dd:d9:dd:c25:c25:94de:b3f5
2472c19:dd:d9:dd:c25:c25:94de:b3f6/1282c19:dd:d9:dd:c25:c25:94de:b3f6
2482c19:dd:d9:dd:c25:c25:94de:b3f7/1282c19:dd:d9:dd:c25:c25:94de:b3f7
2492c19:dd:d9:dd:c25:c25:94de:b3f8/1282c19:dd:d9:dd:c25:c25:94de:b3f8
2502c19:dd:d9:dd:c25:c25:94de:b3f9/1282c19:dd:d9:dd:c25:c25:94de:b3f9
2512c19:dd:d9:dd:c25:c25:94de:b3fa/1282c19:dd:d9:dd:c25:c25:94de:b3fa
2522c19:dd:d9:dd:c25:c25:94de:b3fb/1282c19:dd:d9:dd:c25:c25:94de:b3fb
2532c19:dd:d9:dd:c25:c25:94de:b3fc/1282c19:dd:d9:dd:c25:c25:94de:b3fc
2542c19:dd:d9:dd:c25:c25:94de:b3fd/1282c19:dd:d9:dd:c25:c25:94de:b3fd
2552c19:dd:d9:dd:c25:c25:94de:b3fe/1282c19:dd:d9:dd:c25:c25:94de:b3fe
2562c19:dd:d9:dd:c25:c25:94de:b3ff/1282c19:dd:d9:dd:c25:c25:94de:b3ff

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.