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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:c300/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:c300
Last address
2c19:dd:d9:dd:c25:c25a:d00a:c3ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:c300
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.c.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:c300/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:c300/1282c19:dd:d9:dd:c25:c25a:d00a:c300
22c19:dd:d9:dd:c25:c25a:d00a:c301/1282c19:dd:d9:dd:c25:c25a:d00a:c301
32c19:dd:d9:dd:c25:c25a:d00a:c302/1282c19:dd:d9:dd:c25:c25a:d00a:c302
42c19:dd:d9:dd:c25:c25a:d00a:c303/1282c19:dd:d9:dd:c25:c25a:d00a:c303
52c19:dd:d9:dd:c25:c25a:d00a:c304/1282c19:dd:d9:dd:c25:c25a:d00a:c304
62c19:dd:d9:dd:c25:c25a:d00a:c305/1282c19:dd:d9:dd:c25:c25a:d00a:c305
72c19:dd:d9:dd:c25:c25a:d00a:c306/1282c19:dd:d9:dd:c25:c25a:d00a:c306
82c19:dd:d9:dd:c25:c25a:d00a:c307/1282c19:dd:d9:dd:c25:c25a:d00a:c307
92c19:dd:d9:dd:c25:c25a:d00a:c308/1282c19:dd:d9:dd:c25:c25a:d00a:c308
102c19:dd:d9:dd:c25:c25a:d00a:c309/1282c19:dd:d9:dd:c25:c25a:d00a:c309
112c19:dd:d9:dd:c25:c25a:d00a:c30a/1282c19:dd:d9:dd:c25:c25a:d00a:c30a
122c19:dd:d9:dd:c25:c25a:d00a:c30b/1282c19:dd:d9:dd:c25:c25a:d00a:c30b
132c19:dd:d9:dd:c25:c25a:d00a:c30c/1282c19:dd:d9:dd:c25:c25a:d00a:c30c
142c19:dd:d9:dd:c25:c25a:d00a:c30d/1282c19:dd:d9:dd:c25:c25a:d00a:c30d
152c19:dd:d9:dd:c25:c25a:d00a:c30e/1282c19:dd:d9:dd:c25:c25a:d00a:c30e
162c19:dd:d9:dd:c25:c25a:d00a:c30f/1282c19:dd:d9:dd:c25:c25a:d00a:c30f
172c19:dd:d9:dd:c25:c25a:d00a:c310/1282c19:dd:d9:dd:c25:c25a:d00a:c310
182c19:dd:d9:dd:c25:c25a:d00a:c311/1282c19:dd:d9:dd:c25:c25a:d00a:c311
192c19:dd:d9:dd:c25:c25a:d00a:c312/1282c19:dd:d9:dd:c25:c25a:d00a:c312
202c19:dd:d9:dd:c25:c25a:d00a:c313/1282c19:dd:d9:dd:c25:c25a:d00a:c313
212c19:dd:d9:dd:c25:c25a:d00a:c314/1282c19:dd:d9:dd:c25:c25a:d00a:c314
222c19:dd:d9:dd:c25:c25a:d00a:c315/1282c19:dd:d9:dd:c25:c25a:d00a:c315
232c19:dd:d9:dd:c25:c25a:d00a:c316/1282c19:dd:d9:dd:c25:c25a:d00a:c316
242c19:dd:d9:dd:c25:c25a:d00a:c317/1282c19:dd:d9:dd:c25:c25a:d00a:c317
252c19:dd:d9:dd:c25:c25a:d00a:c318/1282c19:dd:d9:dd:c25:c25a:d00a:c318
262c19:dd:d9:dd:c25:c25a:d00a:c319/1282c19:dd:d9:dd:c25:c25a:d00a:c319
272c19:dd:d9:dd:c25:c25a:d00a:c31a/1282c19:dd:d9:dd:c25:c25a:d00a:c31a
282c19:dd:d9:dd:c25:c25a:d00a:c31b/1282c19:dd:d9:dd:c25:c25a:d00a:c31b
292c19:dd:d9:dd:c25:c25a:d00a:c31c/1282c19:dd:d9:dd:c25:c25a:d00a:c31c
302c19:dd:d9:dd:c25:c25a:d00a:c31d/1282c19:dd:d9:dd:c25:c25a:d00a:c31d
312c19:dd:d9:dd:c25:c25a:d00a:c31e/1282c19:dd:d9:dd:c25:c25a:d00a:c31e
322c19:dd:d9:dd:c25:c25a:d00a:c31f/1282c19:dd:d9:dd:c25:c25a:d00a:c31f
332c19:dd:d9:dd:c25:c25a:d00a:c320/1282c19:dd:d9:dd:c25:c25a:d00a:c320
342c19:dd:d9:dd:c25:c25a:d00a:c321/1282c19:dd:d9:dd:c25:c25a:d00a:c321
352c19:dd:d9:dd:c25:c25a:d00a:c322/1282c19:dd:d9:dd:c25:c25a:d00a:c322
362c19:dd:d9:dd:c25:c25a:d00a:c323/1282c19:dd:d9:dd:c25:c25a:d00a:c323
372c19:dd:d9:dd:c25:c25a:d00a:c324/1282c19:dd:d9:dd:c25:c25a:d00a:c324
382c19:dd:d9:dd:c25:c25a:d00a:c325/1282c19:dd:d9:dd:c25:c25a:d00a:c325
392c19:dd:d9:dd:c25:c25a:d00a:c326/1282c19:dd:d9:dd:c25:c25a:d00a:c326
402c19:dd:d9:dd:c25:c25a:d00a:c327/1282c19:dd:d9:dd:c25:c25a:d00a:c327
412c19:dd:d9:dd:c25:c25a:d00a:c328/1282c19:dd:d9:dd:c25:c25a:d00a:c328
422c19:dd:d9:dd:c25:c25a:d00a:c329/1282c19:dd:d9:dd:c25:c25a:d00a:c329
432c19:dd:d9:dd:c25:c25a:d00a:c32a/1282c19:dd:d9:dd:c25:c25a:d00a:c32a
442c19:dd:d9:dd:c25:c25a:d00a:c32b/1282c19:dd:d9:dd:c25:c25a:d00a:c32b
452c19:dd:d9:dd:c25:c25a:d00a:c32c/1282c19:dd:d9:dd:c25:c25a:d00a:c32c
462c19:dd:d9:dd:c25:c25a:d00a:c32d/1282c19:dd:d9:dd:c25:c25a:d00a:c32d
472c19:dd:d9:dd:c25:c25a:d00a:c32e/1282c19:dd:d9:dd:c25:c25a:d00a:c32e
482c19:dd:d9:dd:c25:c25a:d00a:c32f/1282c19:dd:d9:dd:c25:c25a:d00a:c32f
492c19:dd:d9:dd:c25:c25a:d00a:c330/1282c19:dd:d9:dd:c25:c25a:d00a:c330
502c19:dd:d9:dd:c25:c25a:d00a:c331/1282c19:dd:d9:dd:c25:c25a:d00a:c331
512c19:dd:d9:dd:c25:c25a:d00a:c332/1282c19:dd:d9:dd:c25:c25a:d00a:c332
522c19:dd:d9:dd:c25:c25a:d00a:c333/1282c19:dd:d9:dd:c25:c25a:d00a:c333
532c19:dd:d9:dd:c25:c25a:d00a:c334/1282c19:dd:d9:dd:c25:c25a:d00a:c334
542c19:dd:d9:dd:c25:c25a:d00a:c335/1282c19:dd:d9:dd:c25:c25a:d00a:c335
552c19:dd:d9:dd:c25:c25a:d00a:c336/1282c19:dd:d9:dd:c25:c25a:d00a:c336
562c19:dd:d9:dd:c25:c25a:d00a:c337/1282c19:dd:d9:dd:c25:c25a:d00a:c337
572c19:dd:d9:dd:c25:c25a:d00a:c338/1282c19:dd:d9:dd:c25:c25a:d00a:c338
582c19:dd:d9:dd:c25:c25a:d00a:c339/1282c19:dd:d9:dd:c25:c25a:d00a:c339
592c19:dd:d9:dd:c25:c25a:d00a:c33a/1282c19:dd:d9:dd:c25:c25a:d00a:c33a
602c19:dd:d9:dd:c25:c25a:d00a:c33b/1282c19:dd:d9:dd:c25:c25a:d00a:c33b
612c19:dd:d9:dd:c25:c25a:d00a:c33c/1282c19:dd:d9:dd:c25:c25a:d00a:c33c
622c19:dd:d9:dd:c25:c25a:d00a:c33d/1282c19:dd:d9:dd:c25:c25a:d00a:c33d
632c19:dd:d9:dd:c25:c25a:d00a:c33e/1282c19:dd:d9:dd:c25:c25a:d00a:c33e
642c19:dd:d9:dd:c25:c25a:d00a:c33f/1282c19:dd:d9:dd:c25:c25a:d00a:c33f
652c19:dd:d9:dd:c25:c25a:d00a:c340/1282c19:dd:d9:dd:c25:c25a:d00a:c340
662c19:dd:d9:dd:c25:c25a:d00a:c341/1282c19:dd:d9:dd:c25:c25a:d00a:c341
672c19:dd:d9:dd:c25:c25a:d00a:c342/1282c19:dd:d9:dd:c25:c25a:d00a:c342
682c19:dd:d9:dd:c25:c25a:d00a:c343/1282c19:dd:d9:dd:c25:c25a:d00a:c343
692c19:dd:d9:dd:c25:c25a:d00a:c344/1282c19:dd:d9:dd:c25:c25a:d00a:c344
702c19:dd:d9:dd:c25:c25a:d00a:c345/1282c19:dd:d9:dd:c25:c25a:d00a:c345
712c19:dd:d9:dd:c25:c25a:d00a:c346/1282c19:dd:d9:dd:c25:c25a:d00a:c346
722c19:dd:d9:dd:c25:c25a:d00a:c347/1282c19:dd:d9:dd:c25:c25a:d00a:c347
732c19:dd:d9:dd:c25:c25a:d00a:c348/1282c19:dd:d9:dd:c25:c25a:d00a:c348
742c19:dd:d9:dd:c25:c25a:d00a:c349/1282c19:dd:d9:dd:c25:c25a:d00a:c349
752c19:dd:d9:dd:c25:c25a:d00a:c34a/1282c19:dd:d9:dd:c25:c25a:d00a:c34a
762c19:dd:d9:dd:c25:c25a:d00a:c34b/1282c19:dd:d9:dd:c25:c25a:d00a:c34b
772c19:dd:d9:dd:c25:c25a:d00a:c34c/1282c19:dd:d9:dd:c25:c25a:d00a:c34c
782c19:dd:d9:dd:c25:c25a:d00a:c34d/1282c19:dd:d9:dd:c25:c25a:d00a:c34d
792c19:dd:d9:dd:c25:c25a:d00a:c34e/1282c19:dd:d9:dd:c25:c25a:d00a:c34e
802c19:dd:d9:dd:c25:c25a:d00a:c34f/1282c19:dd:d9:dd:c25:c25a:d00a:c34f
812c19:dd:d9:dd:c25:c25a:d00a:c350/1282c19:dd:d9:dd:c25:c25a:d00a:c350
822c19:dd:d9:dd:c25:c25a:d00a:c351/1282c19:dd:d9:dd:c25:c25a:d00a:c351
832c19:dd:d9:dd:c25:c25a:d00a:c352/1282c19:dd:d9:dd:c25:c25a:d00a:c352
842c19:dd:d9:dd:c25:c25a:d00a:c353/1282c19:dd:d9:dd:c25:c25a:d00a:c353
852c19:dd:d9:dd:c25:c25a:d00a:c354/1282c19:dd:d9:dd:c25:c25a:d00a:c354
862c19:dd:d9:dd:c25:c25a:d00a:c355/1282c19:dd:d9:dd:c25:c25a:d00a:c355
872c19:dd:d9:dd:c25:c25a:d00a:c356/1282c19:dd:d9:dd:c25:c25a:d00a:c356
882c19:dd:d9:dd:c25:c25a:d00a:c357/1282c19:dd:d9:dd:c25:c25a:d00a:c357
892c19:dd:d9:dd:c25:c25a:d00a:c358/1282c19:dd:d9:dd:c25:c25a:d00a:c358
902c19:dd:d9:dd:c25:c25a:d00a:c359/1282c19:dd:d9:dd:c25:c25a:d00a:c359
912c19:dd:d9:dd:c25:c25a:d00a:c35a/1282c19:dd:d9:dd:c25:c25a:d00a:c35a
922c19:dd:d9:dd:c25:c25a:d00a:c35b/1282c19:dd:d9:dd:c25:c25a:d00a:c35b
932c19:dd:d9:dd:c25:c25a:d00a:c35c/1282c19:dd:d9:dd:c25:c25a:d00a:c35c
942c19:dd:d9:dd:c25:c25a:d00a:c35d/1282c19:dd:d9:dd:c25:c25a:d00a:c35d
952c19:dd:d9:dd:c25:c25a:d00a:c35e/1282c19:dd:d9:dd:c25:c25a:d00a:c35e
962c19:dd:d9:dd:c25:c25a:d00a:c35f/1282c19:dd:d9:dd:c25:c25a:d00a:c35f
972c19:dd:d9:dd:c25:c25a:d00a:c360/1282c19:dd:d9:dd:c25:c25a:d00a:c360
982c19:dd:d9:dd:c25:c25a:d00a:c361/1282c19:dd:d9:dd:c25:c25a:d00a:c361
992c19:dd:d9:dd:c25:c25a:d00a:c362/1282c19:dd:d9:dd:c25:c25a:d00a:c362
1002c19:dd:d9:dd:c25:c25a:d00a:c363/1282c19:dd:d9:dd:c25:c25a:d00a:c363
1012c19:dd:d9:dd:c25:c25a:d00a:c364/1282c19:dd:d9:dd:c25:c25a:d00a:c364
1022c19:dd:d9:dd:c25:c25a:d00a:c365/1282c19:dd:d9:dd:c25:c25a:d00a:c365
1032c19:dd:d9:dd:c25:c25a:d00a:c366/1282c19:dd:d9:dd:c25:c25a:d00a:c366
1042c19:dd:d9:dd:c25:c25a:d00a:c367/1282c19:dd:d9:dd:c25:c25a:d00a:c367
1052c19:dd:d9:dd:c25:c25a:d00a:c368/1282c19:dd:d9:dd:c25:c25a:d00a:c368
1062c19:dd:d9:dd:c25:c25a:d00a:c369/1282c19:dd:d9:dd:c25:c25a:d00a:c369
1072c19:dd:d9:dd:c25:c25a:d00a:c36a/1282c19:dd:d9:dd:c25:c25a:d00a:c36a
1082c19:dd:d9:dd:c25:c25a:d00a:c36b/1282c19:dd:d9:dd:c25:c25a:d00a:c36b
1092c19:dd:d9:dd:c25:c25a:d00a:c36c/1282c19:dd:d9:dd:c25:c25a:d00a:c36c
1102c19:dd:d9:dd:c25:c25a:d00a:c36d/1282c19:dd:d9:dd:c25:c25a:d00a:c36d
1112c19:dd:d9:dd:c25:c25a:d00a:c36e/1282c19:dd:d9:dd:c25:c25a:d00a:c36e
1122c19:dd:d9:dd:c25:c25a:d00a:c36f/1282c19:dd:d9:dd:c25:c25a:d00a:c36f
1132c19:dd:d9:dd:c25:c25a:d00a:c370/1282c19:dd:d9:dd:c25:c25a:d00a:c370
1142c19:dd:d9:dd:c25:c25a:d00a:c371/1282c19:dd:d9:dd:c25:c25a:d00a:c371
1152c19:dd:d9:dd:c25:c25a:d00a:c372/1282c19:dd:d9:dd:c25:c25a:d00a:c372
1162c19:dd:d9:dd:c25:c25a:d00a:c373/1282c19:dd:d9:dd:c25:c25a:d00a:c373
1172c19:dd:d9:dd:c25:c25a:d00a:c374/1282c19:dd:d9:dd:c25:c25a:d00a:c374
1182c19:dd:d9:dd:c25:c25a:d00a:c375/1282c19:dd:d9:dd:c25:c25a:d00a:c375
1192c19:dd:d9:dd:c25:c25a:d00a:c376/1282c19:dd:d9:dd:c25:c25a:d00a:c376
1202c19:dd:d9:dd:c25:c25a:d00a:c377/1282c19:dd:d9:dd:c25:c25a:d00a:c377
1212c19:dd:d9:dd:c25:c25a:d00a:c378/1282c19:dd:d9:dd:c25:c25a:d00a:c378
1222c19:dd:d9:dd:c25:c25a:d00a:c379/1282c19:dd:d9:dd:c25:c25a:d00a:c379
1232c19:dd:d9:dd:c25:c25a:d00a:c37a/1282c19:dd:d9:dd:c25:c25a:d00a:c37a
1242c19:dd:d9:dd:c25:c25a:d00a:c37b/1282c19:dd:d9:dd:c25:c25a:d00a:c37b
1252c19:dd:d9:dd:c25:c25a:d00a:c37c/1282c19:dd:d9:dd:c25:c25a:d00a:c37c
1262c19:dd:d9:dd:c25:c25a:d00a:c37d/1282c19:dd:d9:dd:c25:c25a:d00a:c37d
1272c19:dd:d9:dd:c25:c25a:d00a:c37e/1282c19:dd:d9:dd:c25:c25a:d00a:c37e
1282c19:dd:d9:dd:c25:c25a:d00a:c37f/1282c19:dd:d9:dd:c25:c25a:d00a:c37f
1292c19:dd:d9:dd:c25:c25a:d00a:c380/1282c19:dd:d9:dd:c25:c25a:d00a:c380
1302c19:dd:d9:dd:c25:c25a:d00a:c381/1282c19:dd:d9:dd:c25:c25a:d00a:c381
1312c19:dd:d9:dd:c25:c25a:d00a:c382/1282c19:dd:d9:dd:c25:c25a:d00a:c382
1322c19:dd:d9:dd:c25:c25a:d00a:c383/1282c19:dd:d9:dd:c25:c25a:d00a:c383
1332c19:dd:d9:dd:c25:c25a:d00a:c384/1282c19:dd:d9:dd:c25:c25a:d00a:c384
1342c19:dd:d9:dd:c25:c25a:d00a:c385/1282c19:dd:d9:dd:c25:c25a:d00a:c385
1352c19:dd:d9:dd:c25:c25a:d00a:c386/1282c19:dd:d9:dd:c25:c25a:d00a:c386
1362c19:dd:d9:dd:c25:c25a:d00a:c387/1282c19:dd:d9:dd:c25:c25a:d00a:c387
1372c19:dd:d9:dd:c25:c25a:d00a:c388/1282c19:dd:d9:dd:c25:c25a:d00a:c388
1382c19:dd:d9:dd:c25:c25a:d00a:c389/1282c19:dd:d9:dd:c25:c25a:d00a:c389
1392c19:dd:d9:dd:c25:c25a:d00a:c38a/1282c19:dd:d9:dd:c25:c25a:d00a:c38a
1402c19:dd:d9:dd:c25:c25a:d00a:c38b/1282c19:dd:d9:dd:c25:c25a:d00a:c38b
1412c19:dd:d9:dd:c25:c25a:d00a:c38c/1282c19:dd:d9:dd:c25:c25a:d00a:c38c
1422c19:dd:d9:dd:c25:c25a:d00a:c38d/1282c19:dd:d9:dd:c25:c25a:d00a:c38d
1432c19:dd:d9:dd:c25:c25a:d00a:c38e/1282c19:dd:d9:dd:c25:c25a:d00a:c38e
1442c19:dd:d9:dd:c25:c25a:d00a:c38f/1282c19:dd:d9:dd:c25:c25a:d00a:c38f
1452c19:dd:d9:dd:c25:c25a:d00a:c390/1282c19:dd:d9:dd:c25:c25a:d00a:c390
1462c19:dd:d9:dd:c25:c25a:d00a:c391/1282c19:dd:d9:dd:c25:c25a:d00a:c391
1472c19:dd:d9:dd:c25:c25a:d00a:c392/1282c19:dd:d9:dd:c25:c25a:d00a:c392
1482c19:dd:d9:dd:c25:c25a:d00a:c393/1282c19:dd:d9:dd:c25:c25a:d00a:c393
1492c19:dd:d9:dd:c25:c25a:d00a:c394/1282c19:dd:d9:dd:c25:c25a:d00a:c394
1502c19:dd:d9:dd:c25:c25a:d00a:c395/1282c19:dd:d9:dd:c25:c25a:d00a:c395
1512c19:dd:d9:dd:c25:c25a:d00a:c396/1282c19:dd:d9:dd:c25:c25a:d00a:c396
1522c19:dd:d9:dd:c25:c25a:d00a:c397/1282c19:dd:d9:dd:c25:c25a:d00a:c397
1532c19:dd:d9:dd:c25:c25a:d00a:c398/1282c19:dd:d9:dd:c25:c25a:d00a:c398
1542c19:dd:d9:dd:c25:c25a:d00a:c399/1282c19:dd:d9:dd:c25:c25a:d00a:c399
1552c19:dd:d9:dd:c25:c25a:d00a:c39a/1282c19:dd:d9:dd:c25:c25a:d00a:c39a
1562c19:dd:d9:dd:c25:c25a:d00a:c39b/1282c19:dd:d9:dd:c25:c25a:d00a:c39b
1572c19:dd:d9:dd:c25:c25a:d00a:c39c/1282c19:dd:d9:dd:c25:c25a:d00a:c39c
1582c19:dd:d9:dd:c25:c25a:d00a:c39d/1282c19:dd:d9:dd:c25:c25a:d00a:c39d
1592c19:dd:d9:dd:c25:c25a:d00a:c39e/1282c19:dd:d9:dd:c25:c25a:d00a:c39e
1602c19:dd:d9:dd:c25:c25a:d00a:c39f/1282c19:dd:d9:dd:c25:c25a:d00a:c39f
1612c19:dd:d9:dd:c25:c25a:d00a:c3a0/1282c19:dd:d9:dd:c25:c25a:d00a:c3a0
1622c19:dd:d9:dd:c25:c25a:d00a:c3a1/1282c19:dd:d9:dd:c25:c25a:d00a:c3a1
1632c19:dd:d9:dd:c25:c25a:d00a:c3a2/1282c19:dd:d9:dd:c25:c25a:d00a:c3a2
1642c19:dd:d9:dd:c25:c25a:d00a:c3a3/1282c19:dd:d9:dd:c25:c25a:d00a:c3a3
1652c19:dd:d9:dd:c25:c25a:d00a:c3a4/1282c19:dd:d9:dd:c25:c25a:d00a:c3a4
1662c19:dd:d9:dd:c25:c25a:d00a:c3a5/1282c19:dd:d9:dd:c25:c25a:d00a:c3a5
1672c19:dd:d9:dd:c25:c25a:d00a:c3a6/1282c19:dd:d9:dd:c25:c25a:d00a:c3a6
1682c19:dd:d9:dd:c25:c25a:d00a:c3a7/1282c19:dd:d9:dd:c25:c25a:d00a:c3a7
1692c19:dd:d9:dd:c25:c25a:d00a:c3a8/1282c19:dd:d9:dd:c25:c25a:d00a:c3a8
1702c19:dd:d9:dd:c25:c25a:d00a:c3a9/1282c19:dd:d9:dd:c25:c25a:d00a:c3a9
1712c19:dd:d9:dd:c25:c25a:d00a:c3aa/1282c19:dd:d9:dd:c25:c25a:d00a:c3aa
1722c19:dd:d9:dd:c25:c25a:d00a:c3ab/1282c19:dd:d9:dd:c25:c25a:d00a:c3ab
1732c19:dd:d9:dd:c25:c25a:d00a:c3ac/1282c19:dd:d9:dd:c25:c25a:d00a:c3ac
1742c19:dd:d9:dd:c25:c25a:d00a:c3ad/1282c19:dd:d9:dd:c25:c25a:d00a:c3ad
1752c19:dd:d9:dd:c25:c25a:d00a:c3ae/1282c19:dd:d9:dd:c25:c25a:d00a:c3ae
1762c19:dd:d9:dd:c25:c25a:d00a:c3af/1282c19:dd:d9:dd:c25:c25a:d00a:c3af
1772c19:dd:d9:dd:c25:c25a:d00a:c3b0/1282c19:dd:d9:dd:c25:c25a:d00a:c3b0
1782c19:dd:d9:dd:c25:c25a:d00a:c3b1/1282c19:dd:d9:dd:c25:c25a:d00a:c3b1
1792c19:dd:d9:dd:c25:c25a:d00a:c3b2/1282c19:dd:d9:dd:c25:c25a:d00a:c3b2
1802c19:dd:d9:dd:c25:c25a:d00a:c3b3/1282c19:dd:d9:dd:c25:c25a:d00a:c3b3
1812c19:dd:d9:dd:c25:c25a:d00a:c3b4/1282c19:dd:d9:dd:c25:c25a:d00a:c3b4
1822c19:dd:d9:dd:c25:c25a:d00a:c3b5/1282c19:dd:d9:dd:c25:c25a:d00a:c3b5
1832c19:dd:d9:dd:c25:c25a:d00a:c3b6/1282c19:dd:d9:dd:c25:c25a:d00a:c3b6
1842c19:dd:d9:dd:c25:c25a:d00a:c3b7/1282c19:dd:d9:dd:c25:c25a:d00a:c3b7
1852c19:dd:d9:dd:c25:c25a:d00a:c3b8/1282c19:dd:d9:dd:c25:c25a:d00a:c3b8
1862c19:dd:d9:dd:c25:c25a:d00a:c3b9/1282c19:dd:d9:dd:c25:c25a:d00a:c3b9
1872c19:dd:d9:dd:c25:c25a:d00a:c3ba/1282c19:dd:d9:dd:c25:c25a:d00a:c3ba
1882c19:dd:d9:dd:c25:c25a:d00a:c3bb/1282c19:dd:d9:dd:c25:c25a:d00a:c3bb
1892c19:dd:d9:dd:c25:c25a:d00a:c3bc/1282c19:dd:d9:dd:c25:c25a:d00a:c3bc
1902c19:dd:d9:dd:c25:c25a:d00a:c3bd/1282c19:dd:d9:dd:c25:c25a:d00a:c3bd
1912c19:dd:d9:dd:c25:c25a:d00a:c3be/1282c19:dd:d9:dd:c25:c25a:d00a:c3be
1922c19:dd:d9:dd:c25:c25a:d00a:c3bf/1282c19:dd:d9:dd:c25:c25a:d00a:c3bf
1932c19:dd:d9:dd:c25:c25a:d00a:c3c0/1282c19:dd:d9:dd:c25:c25a:d00a:c3c0
1942c19:dd:d9:dd:c25:c25a:d00a:c3c1/1282c19:dd:d9:dd:c25:c25a:d00a:c3c1
1952c19:dd:d9:dd:c25:c25a:d00a:c3c2/1282c19:dd:d9:dd:c25:c25a:d00a:c3c2
1962c19:dd:d9:dd:c25:c25a:d00a:c3c3/1282c19:dd:d9:dd:c25:c25a:d00a:c3c3
1972c19:dd:d9:dd:c25:c25a:d00a:c3c4/1282c19:dd:d9:dd:c25:c25a:d00a:c3c4
1982c19:dd:d9:dd:c25:c25a:d00a:c3c5/1282c19:dd:d9:dd:c25:c25a:d00a:c3c5
1992c19:dd:d9:dd:c25:c25a:d00a:c3c6/1282c19:dd:d9:dd:c25:c25a:d00a:c3c6
2002c19:dd:d9:dd:c25:c25a:d00a:c3c7/1282c19:dd:d9:dd:c25:c25a:d00a:c3c7
2012c19:dd:d9:dd:c25:c25a:d00a:c3c8/1282c19:dd:d9:dd:c25:c25a:d00a:c3c8
2022c19:dd:d9:dd:c25:c25a:d00a:c3c9/1282c19:dd:d9:dd:c25:c25a:d00a:c3c9
2032c19:dd:d9:dd:c25:c25a:d00a:c3ca/1282c19:dd:d9:dd:c25:c25a:d00a:c3ca
2042c19:dd:d9:dd:c25:c25a:d00a:c3cb/1282c19:dd:d9:dd:c25:c25a:d00a:c3cb
2052c19:dd:d9:dd:c25:c25a:d00a:c3cc/1282c19:dd:d9:dd:c25:c25a:d00a:c3cc
2062c19:dd:d9:dd:c25:c25a:d00a:c3cd/1282c19:dd:d9:dd:c25:c25a:d00a:c3cd
2072c19:dd:d9:dd:c25:c25a:d00a:c3ce/1282c19:dd:d9:dd:c25:c25a:d00a:c3ce
2082c19:dd:d9:dd:c25:c25a:d00a:c3cf/1282c19:dd:d9:dd:c25:c25a:d00a:c3cf
2092c19:dd:d9:dd:c25:c25a:d00a:c3d0/1282c19:dd:d9:dd:c25:c25a:d00a:c3d0
2102c19:dd:d9:dd:c25:c25a:d00a:c3d1/1282c19:dd:d9:dd:c25:c25a:d00a:c3d1
2112c19:dd:d9:dd:c25:c25a:d00a:c3d2/1282c19:dd:d9:dd:c25:c25a:d00a:c3d2
2122c19:dd:d9:dd:c25:c25a:d00a:c3d3/1282c19:dd:d9:dd:c25:c25a:d00a:c3d3
2132c19:dd:d9:dd:c25:c25a:d00a:c3d4/1282c19:dd:d9:dd:c25:c25a:d00a:c3d4
2142c19:dd:d9:dd:c25:c25a:d00a:c3d5/1282c19:dd:d9:dd:c25:c25a:d00a:c3d5
2152c19:dd:d9:dd:c25:c25a:d00a:c3d6/1282c19:dd:d9:dd:c25:c25a:d00a:c3d6
2162c19:dd:d9:dd:c25:c25a:d00a:c3d7/1282c19:dd:d9:dd:c25:c25a:d00a:c3d7
2172c19:dd:d9:dd:c25:c25a:d00a:c3d8/1282c19:dd:d9:dd:c25:c25a:d00a:c3d8
2182c19:dd:d9:dd:c25:c25a:d00a:c3d9/1282c19:dd:d9:dd:c25:c25a:d00a:c3d9
2192c19:dd:d9:dd:c25:c25a:d00a:c3da/1282c19:dd:d9:dd:c25:c25a:d00a:c3da
2202c19:dd:d9:dd:c25:c25a:d00a:c3db/1282c19:dd:d9:dd:c25:c25a:d00a:c3db
2212c19:dd:d9:dd:c25:c25a:d00a:c3dc/1282c19:dd:d9:dd:c25:c25a:d00a:c3dc
2222c19:dd:d9:dd:c25:c25a:d00a:c3dd/1282c19:dd:d9:dd:c25:c25a:d00a:c3dd
2232c19:dd:d9:dd:c25:c25a:d00a:c3de/1282c19:dd:d9:dd:c25:c25a:d00a:c3de
2242c19:dd:d9:dd:c25:c25a:d00a:c3df/1282c19:dd:d9:dd:c25:c25a:d00a:c3df
2252c19:dd:d9:dd:c25:c25a:d00a:c3e0/1282c19:dd:d9:dd:c25:c25a:d00a:c3e0
2262c19:dd:d9:dd:c25:c25a:d00a:c3e1/1282c19:dd:d9:dd:c25:c25a:d00a:c3e1
2272c19:dd:d9:dd:c25:c25a:d00a:c3e2/1282c19:dd:d9:dd:c25:c25a:d00a:c3e2
2282c19:dd:d9:dd:c25:c25a:d00a:c3e3/1282c19:dd:d9:dd:c25:c25a:d00a:c3e3
2292c19:dd:d9:dd:c25:c25a:d00a:c3e4/1282c19:dd:d9:dd:c25:c25a:d00a:c3e4
2302c19:dd:d9:dd:c25:c25a:d00a:c3e5/1282c19:dd:d9:dd:c25:c25a:d00a:c3e5
2312c19:dd:d9:dd:c25:c25a:d00a:c3e6/1282c19:dd:d9:dd:c25:c25a:d00a:c3e6
2322c19:dd:d9:dd:c25:c25a:d00a:c3e7/1282c19:dd:d9:dd:c25:c25a:d00a:c3e7
2332c19:dd:d9:dd:c25:c25a:d00a:c3e8/1282c19:dd:d9:dd:c25:c25a:d00a:c3e8
2342c19:dd:d9:dd:c25:c25a:d00a:c3e9/1282c19:dd:d9:dd:c25:c25a:d00a:c3e9
2352c19:dd:d9:dd:c25:c25a:d00a:c3ea/1282c19:dd:d9:dd:c25:c25a:d00a:c3ea
2362c19:dd:d9:dd:c25:c25a:d00a:c3eb/1282c19:dd:d9:dd:c25:c25a:d00a:c3eb
2372c19:dd:d9:dd:c25:c25a:d00a:c3ec/1282c19:dd:d9:dd:c25:c25a:d00a:c3ec
2382c19:dd:d9:dd:c25:c25a:d00a:c3ed/1282c19:dd:d9:dd:c25:c25a:d00a:c3ed
2392c19:dd:d9:dd:c25:c25a:d00a:c3ee/1282c19:dd:d9:dd:c25:c25a:d00a:c3ee
2402c19:dd:d9:dd:c25:c25a:d00a:c3ef/1282c19:dd:d9:dd:c25:c25a:d00a:c3ef
2412c19:dd:d9:dd:c25:c25a:d00a:c3f0/1282c19:dd:d9:dd:c25:c25a:d00a:c3f0
2422c19:dd:d9:dd:c25:c25a:d00a:c3f1/1282c19:dd:d9:dd:c25:c25a:d00a:c3f1
2432c19:dd:d9:dd:c25:c25a:d00a:c3f2/1282c19:dd:d9:dd:c25:c25a:d00a:c3f2
2442c19:dd:d9:dd:c25:c25a:d00a:c3f3/1282c19:dd:d9:dd:c25:c25a:d00a:c3f3
2452c19:dd:d9:dd:c25:c25a:d00a:c3f4/1282c19:dd:d9:dd:c25:c25a:d00a:c3f4
2462c19:dd:d9:dd:c25:c25a:d00a:c3f5/1282c19:dd:d9:dd:c25:c25a:d00a:c3f5
2472c19:dd:d9:dd:c25:c25a:d00a:c3f6/1282c19:dd:d9:dd:c25:c25a:d00a:c3f6
2482c19:dd:d9:dd:c25:c25a:d00a:c3f7/1282c19:dd:d9:dd:c25:c25a:d00a:c3f7
2492c19:dd:d9:dd:c25:c25a:d00a:c3f8/1282c19:dd:d9:dd:c25:c25a:d00a:c3f8
2502c19:dd:d9:dd:c25:c25a:d00a:c3f9/1282c19:dd:d9:dd:c25:c25a:d00a:c3f9
2512c19:dd:d9:dd:c25:c25a:d00a:c3fa/1282c19:dd:d9:dd:c25:c25a:d00a:c3fa
2522c19:dd:d9:dd:c25:c25a:d00a:c3fb/1282c19:dd:d9:dd:c25:c25a:d00a:c3fb
2532c19:dd:d9:dd:c25:c25a:d00a:c3fc/1282c19:dd:d9:dd:c25:c25a:d00a:c3fc
2542c19:dd:d9:dd:c25:c25a:d00a:c3fd/1282c19:dd:d9:dd:c25:c25a:d00a:c3fd
2552c19:dd:d9:dd:c25:c25a:d00a:c3fe/1282c19:dd:d9:dd:c25:c25a:d00a:c3fe
2562c19:dd:d9:dd:c25:c25a:d00a:c3ff/1282c19:dd:d9:dd:c25:c25a:d00a:c3ff

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.