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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:9300/120
First address
2c19:dd:d9:dd:c25:c25:94de:9300
Last address
2c19:dd:d9:dd:c25:c25:94de:93ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:9300
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.9.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:9300/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:9300/1282c19:dd:d9:dd:c25:c25:94de:9300
22c19:dd:d9:dd:c25:c25:94de:9301/1282c19:dd:d9:dd:c25:c25:94de:9301
32c19:dd:d9:dd:c25:c25:94de:9302/1282c19:dd:d9:dd:c25:c25:94de:9302
42c19:dd:d9:dd:c25:c25:94de:9303/1282c19:dd:d9:dd:c25:c25:94de:9303
52c19:dd:d9:dd:c25:c25:94de:9304/1282c19:dd:d9:dd:c25:c25:94de:9304
62c19:dd:d9:dd:c25:c25:94de:9305/1282c19:dd:d9:dd:c25:c25:94de:9305
72c19:dd:d9:dd:c25:c25:94de:9306/1282c19:dd:d9:dd:c25:c25:94de:9306
82c19:dd:d9:dd:c25:c25:94de:9307/1282c19:dd:d9:dd:c25:c25:94de:9307
92c19:dd:d9:dd:c25:c25:94de:9308/1282c19:dd:d9:dd:c25:c25:94de:9308
102c19:dd:d9:dd:c25:c25:94de:9309/1282c19:dd:d9:dd:c25:c25:94de:9309
112c19:dd:d9:dd:c25:c25:94de:930a/1282c19:dd:d9:dd:c25:c25:94de:930a
122c19:dd:d9:dd:c25:c25:94de:930b/1282c19:dd:d9:dd:c25:c25:94de:930b
132c19:dd:d9:dd:c25:c25:94de:930c/1282c19:dd:d9:dd:c25:c25:94de:930c
142c19:dd:d9:dd:c25:c25:94de:930d/1282c19:dd:d9:dd:c25:c25:94de:930d
152c19:dd:d9:dd:c25:c25:94de:930e/1282c19:dd:d9:dd:c25:c25:94de:930e
162c19:dd:d9:dd:c25:c25:94de:930f/1282c19:dd:d9:dd:c25:c25:94de:930f
172c19:dd:d9:dd:c25:c25:94de:9310/1282c19:dd:d9:dd:c25:c25:94de:9310
182c19:dd:d9:dd:c25:c25:94de:9311/1282c19:dd:d9:dd:c25:c25:94de:9311
192c19:dd:d9:dd:c25:c25:94de:9312/1282c19:dd:d9:dd:c25:c25:94de:9312
202c19:dd:d9:dd:c25:c25:94de:9313/1282c19:dd:d9:dd:c25:c25:94de:9313
212c19:dd:d9:dd:c25:c25:94de:9314/1282c19:dd:d9:dd:c25:c25:94de:9314
222c19:dd:d9:dd:c25:c25:94de:9315/1282c19:dd:d9:dd:c25:c25:94de:9315
232c19:dd:d9:dd:c25:c25:94de:9316/1282c19:dd:d9:dd:c25:c25:94de:9316
242c19:dd:d9:dd:c25:c25:94de:9317/1282c19:dd:d9:dd:c25:c25:94de:9317
252c19:dd:d9:dd:c25:c25:94de:9318/1282c19:dd:d9:dd:c25:c25:94de:9318
262c19:dd:d9:dd:c25:c25:94de:9319/1282c19:dd:d9:dd:c25:c25:94de:9319
272c19:dd:d9:dd:c25:c25:94de:931a/1282c19:dd:d9:dd:c25:c25:94de:931a
282c19:dd:d9:dd:c25:c25:94de:931b/1282c19:dd:d9:dd:c25:c25:94de:931b
292c19:dd:d9:dd:c25:c25:94de:931c/1282c19:dd:d9:dd:c25:c25:94de:931c
302c19:dd:d9:dd:c25:c25:94de:931d/1282c19:dd:d9:dd:c25:c25:94de:931d
312c19:dd:d9:dd:c25:c25:94de:931e/1282c19:dd:d9:dd:c25:c25:94de:931e
322c19:dd:d9:dd:c25:c25:94de:931f/1282c19:dd:d9:dd:c25:c25:94de:931f
332c19:dd:d9:dd:c25:c25:94de:9320/1282c19:dd:d9:dd:c25:c25:94de:9320
342c19:dd:d9:dd:c25:c25:94de:9321/1282c19:dd:d9:dd:c25:c25:94de:9321
352c19:dd:d9:dd:c25:c25:94de:9322/1282c19:dd:d9:dd:c25:c25:94de:9322
362c19:dd:d9:dd:c25:c25:94de:9323/1282c19:dd:d9:dd:c25:c25:94de:9323
372c19:dd:d9:dd:c25:c25:94de:9324/1282c19:dd:d9:dd:c25:c25:94de:9324
382c19:dd:d9:dd:c25:c25:94de:9325/1282c19:dd:d9:dd:c25:c25:94de:9325
392c19:dd:d9:dd:c25:c25:94de:9326/1282c19:dd:d9:dd:c25:c25:94de:9326
402c19:dd:d9:dd:c25:c25:94de:9327/1282c19:dd:d9:dd:c25:c25:94de:9327
412c19:dd:d9:dd:c25:c25:94de:9328/1282c19:dd:d9:dd:c25:c25:94de:9328
422c19:dd:d9:dd:c25:c25:94de:9329/1282c19:dd:d9:dd:c25:c25:94de:9329
432c19:dd:d9:dd:c25:c25:94de:932a/1282c19:dd:d9:dd:c25:c25:94de:932a
442c19:dd:d9:dd:c25:c25:94de:932b/1282c19:dd:d9:dd:c25:c25:94de:932b
452c19:dd:d9:dd:c25:c25:94de:932c/1282c19:dd:d9:dd:c25:c25:94de:932c
462c19:dd:d9:dd:c25:c25:94de:932d/1282c19:dd:d9:dd:c25:c25:94de:932d
472c19:dd:d9:dd:c25:c25:94de:932e/1282c19:dd:d9:dd:c25:c25:94de:932e
482c19:dd:d9:dd:c25:c25:94de:932f/1282c19:dd:d9:dd:c25:c25:94de:932f
492c19:dd:d9:dd:c25:c25:94de:9330/1282c19:dd:d9:dd:c25:c25:94de:9330
502c19:dd:d9:dd:c25:c25:94de:9331/1282c19:dd:d9:dd:c25:c25:94de:9331
512c19:dd:d9:dd:c25:c25:94de:9332/1282c19:dd:d9:dd:c25:c25:94de:9332
522c19:dd:d9:dd:c25:c25:94de:9333/1282c19:dd:d9:dd:c25:c25:94de:9333
532c19:dd:d9:dd:c25:c25:94de:9334/1282c19:dd:d9:dd:c25:c25:94de:9334
542c19:dd:d9:dd:c25:c25:94de:9335/1282c19:dd:d9:dd:c25:c25:94de:9335
552c19:dd:d9:dd:c25:c25:94de:9336/1282c19:dd:d9:dd:c25:c25:94de:9336
562c19:dd:d9:dd:c25:c25:94de:9337/1282c19:dd:d9:dd:c25:c25:94de:9337
572c19:dd:d9:dd:c25:c25:94de:9338/1282c19:dd:d9:dd:c25:c25:94de:9338
582c19:dd:d9:dd:c25:c25:94de:9339/1282c19:dd:d9:dd:c25:c25:94de:9339
592c19:dd:d9:dd:c25:c25:94de:933a/1282c19:dd:d9:dd:c25:c25:94de:933a
602c19:dd:d9:dd:c25:c25:94de:933b/1282c19:dd:d9:dd:c25:c25:94de:933b
612c19:dd:d9:dd:c25:c25:94de:933c/1282c19:dd:d9:dd:c25:c25:94de:933c
622c19:dd:d9:dd:c25:c25:94de:933d/1282c19:dd:d9:dd:c25:c25:94de:933d
632c19:dd:d9:dd:c25:c25:94de:933e/1282c19:dd:d9:dd:c25:c25:94de:933e
642c19:dd:d9:dd:c25:c25:94de:933f/1282c19:dd:d9:dd:c25:c25:94de:933f
652c19:dd:d9:dd:c25:c25:94de:9340/1282c19:dd:d9:dd:c25:c25:94de:9340
662c19:dd:d9:dd:c25:c25:94de:9341/1282c19:dd:d9:dd:c25:c25:94de:9341
672c19:dd:d9:dd:c25:c25:94de:9342/1282c19:dd:d9:dd:c25:c25:94de:9342
682c19:dd:d9:dd:c25:c25:94de:9343/1282c19:dd:d9:dd:c25:c25:94de:9343
692c19:dd:d9:dd:c25:c25:94de:9344/1282c19:dd:d9:dd:c25:c25:94de:9344
702c19:dd:d9:dd:c25:c25:94de:9345/1282c19:dd:d9:dd:c25:c25:94de:9345
712c19:dd:d9:dd:c25:c25:94de:9346/1282c19:dd:d9:dd:c25:c25:94de:9346
722c19:dd:d9:dd:c25:c25:94de:9347/1282c19:dd:d9:dd:c25:c25:94de:9347
732c19:dd:d9:dd:c25:c25:94de:9348/1282c19:dd:d9:dd:c25:c25:94de:9348
742c19:dd:d9:dd:c25:c25:94de:9349/1282c19:dd:d9:dd:c25:c25:94de:9349
752c19:dd:d9:dd:c25:c25:94de:934a/1282c19:dd:d9:dd:c25:c25:94de:934a
762c19:dd:d9:dd:c25:c25:94de:934b/1282c19:dd:d9:dd:c25:c25:94de:934b
772c19:dd:d9:dd:c25:c25:94de:934c/1282c19:dd:d9:dd:c25:c25:94de:934c
782c19:dd:d9:dd:c25:c25:94de:934d/1282c19:dd:d9:dd:c25:c25:94de:934d
792c19:dd:d9:dd:c25:c25:94de:934e/1282c19:dd:d9:dd:c25:c25:94de:934e
802c19:dd:d9:dd:c25:c25:94de:934f/1282c19:dd:d9:dd:c25:c25:94de:934f
812c19:dd:d9:dd:c25:c25:94de:9350/1282c19:dd:d9:dd:c25:c25:94de:9350
822c19:dd:d9:dd:c25:c25:94de:9351/1282c19:dd:d9:dd:c25:c25:94de:9351
832c19:dd:d9:dd:c25:c25:94de:9352/1282c19:dd:d9:dd:c25:c25:94de:9352
842c19:dd:d9:dd:c25:c25:94de:9353/1282c19:dd:d9:dd:c25:c25:94de:9353
852c19:dd:d9:dd:c25:c25:94de:9354/1282c19:dd:d9:dd:c25:c25:94de:9354
862c19:dd:d9:dd:c25:c25:94de:9355/1282c19:dd:d9:dd:c25:c25:94de:9355
872c19:dd:d9:dd:c25:c25:94de:9356/1282c19:dd:d9:dd:c25:c25:94de:9356
882c19:dd:d9:dd:c25:c25:94de:9357/1282c19:dd:d9:dd:c25:c25:94de:9357
892c19:dd:d9:dd:c25:c25:94de:9358/1282c19:dd:d9:dd:c25:c25:94de:9358
902c19:dd:d9:dd:c25:c25:94de:9359/1282c19:dd:d9:dd:c25:c25:94de:9359
912c19:dd:d9:dd:c25:c25:94de:935a/1282c19:dd:d9:dd:c25:c25:94de:935a
922c19:dd:d9:dd:c25:c25:94de:935b/1282c19:dd:d9:dd:c25:c25:94de:935b
932c19:dd:d9:dd:c25:c25:94de:935c/1282c19:dd:d9:dd:c25:c25:94de:935c
942c19:dd:d9:dd:c25:c25:94de:935d/1282c19:dd:d9:dd:c25:c25:94de:935d
952c19:dd:d9:dd:c25:c25:94de:935e/1282c19:dd:d9:dd:c25:c25:94de:935e
962c19:dd:d9:dd:c25:c25:94de:935f/1282c19:dd:d9:dd:c25:c25:94de:935f
972c19:dd:d9:dd:c25:c25:94de:9360/1282c19:dd:d9:dd:c25:c25:94de:9360
982c19:dd:d9:dd:c25:c25:94de:9361/1282c19:dd:d9:dd:c25:c25:94de:9361
992c19:dd:d9:dd:c25:c25:94de:9362/1282c19:dd:d9:dd:c25:c25:94de:9362
1002c19:dd:d9:dd:c25:c25:94de:9363/1282c19:dd:d9:dd:c25:c25:94de:9363
1012c19:dd:d9:dd:c25:c25:94de:9364/1282c19:dd:d9:dd:c25:c25:94de:9364
1022c19:dd:d9:dd:c25:c25:94de:9365/1282c19:dd:d9:dd:c25:c25:94de:9365
1032c19:dd:d9:dd:c25:c25:94de:9366/1282c19:dd:d9:dd:c25:c25:94de:9366
1042c19:dd:d9:dd:c25:c25:94de:9367/1282c19:dd:d9:dd:c25:c25:94de:9367
1052c19:dd:d9:dd:c25:c25:94de:9368/1282c19:dd:d9:dd:c25:c25:94de:9368
1062c19:dd:d9:dd:c25:c25:94de:9369/1282c19:dd:d9:dd:c25:c25:94de:9369
1072c19:dd:d9:dd:c25:c25:94de:936a/1282c19:dd:d9:dd:c25:c25:94de:936a
1082c19:dd:d9:dd:c25:c25:94de:936b/1282c19:dd:d9:dd:c25:c25:94de:936b
1092c19:dd:d9:dd:c25:c25:94de:936c/1282c19:dd:d9:dd:c25:c25:94de:936c
1102c19:dd:d9:dd:c25:c25:94de:936d/1282c19:dd:d9:dd:c25:c25:94de:936d
1112c19:dd:d9:dd:c25:c25:94de:936e/1282c19:dd:d9:dd:c25:c25:94de:936e
1122c19:dd:d9:dd:c25:c25:94de:936f/1282c19:dd:d9:dd:c25:c25:94de:936f
1132c19:dd:d9:dd:c25:c25:94de:9370/1282c19:dd:d9:dd:c25:c25:94de:9370
1142c19:dd:d9:dd:c25:c25:94de:9371/1282c19:dd:d9:dd:c25:c25:94de:9371
1152c19:dd:d9:dd:c25:c25:94de:9372/1282c19:dd:d9:dd:c25:c25:94de:9372
1162c19:dd:d9:dd:c25:c25:94de:9373/1282c19:dd:d9:dd:c25:c25:94de:9373
1172c19:dd:d9:dd:c25:c25:94de:9374/1282c19:dd:d9:dd:c25:c25:94de:9374
1182c19:dd:d9:dd:c25:c25:94de:9375/1282c19:dd:d9:dd:c25:c25:94de:9375
1192c19:dd:d9:dd:c25:c25:94de:9376/1282c19:dd:d9:dd:c25:c25:94de:9376
1202c19:dd:d9:dd:c25:c25:94de:9377/1282c19:dd:d9:dd:c25:c25:94de:9377
1212c19:dd:d9:dd:c25:c25:94de:9378/1282c19:dd:d9:dd:c25:c25:94de:9378
1222c19:dd:d9:dd:c25:c25:94de:9379/1282c19:dd:d9:dd:c25:c25:94de:9379
1232c19:dd:d9:dd:c25:c25:94de:937a/1282c19:dd:d9:dd:c25:c25:94de:937a
1242c19:dd:d9:dd:c25:c25:94de:937b/1282c19:dd:d9:dd:c25:c25:94de:937b
1252c19:dd:d9:dd:c25:c25:94de:937c/1282c19:dd:d9:dd:c25:c25:94de:937c
1262c19:dd:d9:dd:c25:c25:94de:937d/1282c19:dd:d9:dd:c25:c25:94de:937d
1272c19:dd:d9:dd:c25:c25:94de:937e/1282c19:dd:d9:dd:c25:c25:94de:937e
1282c19:dd:d9:dd:c25:c25:94de:937f/1282c19:dd:d9:dd:c25:c25:94de:937f
1292c19:dd:d9:dd:c25:c25:94de:9380/1282c19:dd:d9:dd:c25:c25:94de:9380
1302c19:dd:d9:dd:c25:c25:94de:9381/1282c19:dd:d9:dd:c25:c25:94de:9381
1312c19:dd:d9:dd:c25:c25:94de:9382/1282c19:dd:d9:dd:c25:c25:94de:9382
1322c19:dd:d9:dd:c25:c25:94de:9383/1282c19:dd:d9:dd:c25:c25:94de:9383
1332c19:dd:d9:dd:c25:c25:94de:9384/1282c19:dd:d9:dd:c25:c25:94de:9384
1342c19:dd:d9:dd:c25:c25:94de:9385/1282c19:dd:d9:dd:c25:c25:94de:9385
1352c19:dd:d9:dd:c25:c25:94de:9386/1282c19:dd:d9:dd:c25:c25:94de:9386
1362c19:dd:d9:dd:c25:c25:94de:9387/1282c19:dd:d9:dd:c25:c25:94de:9387
1372c19:dd:d9:dd:c25:c25:94de:9388/1282c19:dd:d9:dd:c25:c25:94de:9388
1382c19:dd:d9:dd:c25:c25:94de:9389/1282c19:dd:d9:dd:c25:c25:94de:9389
1392c19:dd:d9:dd:c25:c25:94de:938a/1282c19:dd:d9:dd:c25:c25:94de:938a
1402c19:dd:d9:dd:c25:c25:94de:938b/1282c19:dd:d9:dd:c25:c25:94de:938b
1412c19:dd:d9:dd:c25:c25:94de:938c/1282c19:dd:d9:dd:c25:c25:94de:938c
1422c19:dd:d9:dd:c25:c25:94de:938d/1282c19:dd:d9:dd:c25:c25:94de:938d
1432c19:dd:d9:dd:c25:c25:94de:938e/1282c19:dd:d9:dd:c25:c25:94de:938e
1442c19:dd:d9:dd:c25:c25:94de:938f/1282c19:dd:d9:dd:c25:c25:94de:938f
1452c19:dd:d9:dd:c25:c25:94de:9390/1282c19:dd:d9:dd:c25:c25:94de:9390
1462c19:dd:d9:dd:c25:c25:94de:9391/1282c19:dd:d9:dd:c25:c25:94de:9391
1472c19:dd:d9:dd:c25:c25:94de:9392/1282c19:dd:d9:dd:c25:c25:94de:9392
1482c19:dd:d9:dd:c25:c25:94de:9393/1282c19:dd:d9:dd:c25:c25:94de:9393
1492c19:dd:d9:dd:c25:c25:94de:9394/1282c19:dd:d9:dd:c25:c25:94de:9394
1502c19:dd:d9:dd:c25:c25:94de:9395/1282c19:dd:d9:dd:c25:c25:94de:9395
1512c19:dd:d9:dd:c25:c25:94de:9396/1282c19:dd:d9:dd:c25:c25:94de:9396
1522c19:dd:d9:dd:c25:c25:94de:9397/1282c19:dd:d9:dd:c25:c25:94de:9397
1532c19:dd:d9:dd:c25:c25:94de:9398/1282c19:dd:d9:dd:c25:c25:94de:9398
1542c19:dd:d9:dd:c25:c25:94de:9399/1282c19:dd:d9:dd:c25:c25:94de:9399
1552c19:dd:d9:dd:c25:c25:94de:939a/1282c19:dd:d9:dd:c25:c25:94de:939a
1562c19:dd:d9:dd:c25:c25:94de:939b/1282c19:dd:d9:dd:c25:c25:94de:939b
1572c19:dd:d9:dd:c25:c25:94de:939c/1282c19:dd:d9:dd:c25:c25:94de:939c
1582c19:dd:d9:dd:c25:c25:94de:939d/1282c19:dd:d9:dd:c25:c25:94de:939d
1592c19:dd:d9:dd:c25:c25:94de:939e/1282c19:dd:d9:dd:c25:c25:94de:939e
1602c19:dd:d9:dd:c25:c25:94de:939f/1282c19:dd:d9:dd:c25:c25:94de:939f
1612c19:dd:d9:dd:c25:c25:94de:93a0/1282c19:dd:d9:dd:c25:c25:94de:93a0
1622c19:dd:d9:dd:c25:c25:94de:93a1/1282c19:dd:d9:dd:c25:c25:94de:93a1
1632c19:dd:d9:dd:c25:c25:94de:93a2/1282c19:dd:d9:dd:c25:c25:94de:93a2
1642c19:dd:d9:dd:c25:c25:94de:93a3/1282c19:dd:d9:dd:c25:c25:94de:93a3
1652c19:dd:d9:dd:c25:c25:94de:93a4/1282c19:dd:d9:dd:c25:c25:94de:93a4
1662c19:dd:d9:dd:c25:c25:94de:93a5/1282c19:dd:d9:dd:c25:c25:94de:93a5
1672c19:dd:d9:dd:c25:c25:94de:93a6/1282c19:dd:d9:dd:c25:c25:94de:93a6
1682c19:dd:d9:dd:c25:c25:94de:93a7/1282c19:dd:d9:dd:c25:c25:94de:93a7
1692c19:dd:d9:dd:c25:c25:94de:93a8/1282c19:dd:d9:dd:c25:c25:94de:93a8
1702c19:dd:d9:dd:c25:c25:94de:93a9/1282c19:dd:d9:dd:c25:c25:94de:93a9
1712c19:dd:d9:dd:c25:c25:94de:93aa/1282c19:dd:d9:dd:c25:c25:94de:93aa
1722c19:dd:d9:dd:c25:c25:94de:93ab/1282c19:dd:d9:dd:c25:c25:94de:93ab
1732c19:dd:d9:dd:c25:c25:94de:93ac/1282c19:dd:d9:dd:c25:c25:94de:93ac
1742c19:dd:d9:dd:c25:c25:94de:93ad/1282c19:dd:d9:dd:c25:c25:94de:93ad
1752c19:dd:d9:dd:c25:c25:94de:93ae/1282c19:dd:d9:dd:c25:c25:94de:93ae
1762c19:dd:d9:dd:c25:c25:94de:93af/1282c19:dd:d9:dd:c25:c25:94de:93af
1772c19:dd:d9:dd:c25:c25:94de:93b0/1282c19:dd:d9:dd:c25:c25:94de:93b0
1782c19:dd:d9:dd:c25:c25:94de:93b1/1282c19:dd:d9:dd:c25:c25:94de:93b1
1792c19:dd:d9:dd:c25:c25:94de:93b2/1282c19:dd:d9:dd:c25:c25:94de:93b2
1802c19:dd:d9:dd:c25:c25:94de:93b3/1282c19:dd:d9:dd:c25:c25:94de:93b3
1812c19:dd:d9:dd:c25:c25:94de:93b4/1282c19:dd:d9:dd:c25:c25:94de:93b4
1822c19:dd:d9:dd:c25:c25:94de:93b5/1282c19:dd:d9:dd:c25:c25:94de:93b5
1832c19:dd:d9:dd:c25:c25:94de:93b6/1282c19:dd:d9:dd:c25:c25:94de:93b6
1842c19:dd:d9:dd:c25:c25:94de:93b7/1282c19:dd:d9:dd:c25:c25:94de:93b7
1852c19:dd:d9:dd:c25:c25:94de:93b8/1282c19:dd:d9:dd:c25:c25:94de:93b8
1862c19:dd:d9:dd:c25:c25:94de:93b9/1282c19:dd:d9:dd:c25:c25:94de:93b9
1872c19:dd:d9:dd:c25:c25:94de:93ba/1282c19:dd:d9:dd:c25:c25:94de:93ba
1882c19:dd:d9:dd:c25:c25:94de:93bb/1282c19:dd:d9:dd:c25:c25:94de:93bb
1892c19:dd:d9:dd:c25:c25:94de:93bc/1282c19:dd:d9:dd:c25:c25:94de:93bc
1902c19:dd:d9:dd:c25:c25:94de:93bd/1282c19:dd:d9:dd:c25:c25:94de:93bd
1912c19:dd:d9:dd:c25:c25:94de:93be/1282c19:dd:d9:dd:c25:c25:94de:93be
1922c19:dd:d9:dd:c25:c25:94de:93bf/1282c19:dd:d9:dd:c25:c25:94de:93bf
1932c19:dd:d9:dd:c25:c25:94de:93c0/1282c19:dd:d9:dd:c25:c25:94de:93c0
1942c19:dd:d9:dd:c25:c25:94de:93c1/1282c19:dd:d9:dd:c25:c25:94de:93c1
1952c19:dd:d9:dd:c25:c25:94de:93c2/1282c19:dd:d9:dd:c25:c25:94de:93c2
1962c19:dd:d9:dd:c25:c25:94de:93c3/1282c19:dd:d9:dd:c25:c25:94de:93c3
1972c19:dd:d9:dd:c25:c25:94de:93c4/1282c19:dd:d9:dd:c25:c25:94de:93c4
1982c19:dd:d9:dd:c25:c25:94de:93c5/1282c19:dd:d9:dd:c25:c25:94de:93c5
1992c19:dd:d9:dd:c25:c25:94de:93c6/1282c19:dd:d9:dd:c25:c25:94de:93c6
2002c19:dd:d9:dd:c25:c25:94de:93c7/1282c19:dd:d9:dd:c25:c25:94de:93c7
2012c19:dd:d9:dd:c25:c25:94de:93c8/1282c19:dd:d9:dd:c25:c25:94de:93c8
2022c19:dd:d9:dd:c25:c25:94de:93c9/1282c19:dd:d9:dd:c25:c25:94de:93c9
2032c19:dd:d9:dd:c25:c25:94de:93ca/1282c19:dd:d9:dd:c25:c25:94de:93ca
2042c19:dd:d9:dd:c25:c25:94de:93cb/1282c19:dd:d9:dd:c25:c25:94de:93cb
2052c19:dd:d9:dd:c25:c25:94de:93cc/1282c19:dd:d9:dd:c25:c25:94de:93cc
2062c19:dd:d9:dd:c25:c25:94de:93cd/1282c19:dd:d9:dd:c25:c25:94de:93cd
2072c19:dd:d9:dd:c25:c25:94de:93ce/1282c19:dd:d9:dd:c25:c25:94de:93ce
2082c19:dd:d9:dd:c25:c25:94de:93cf/1282c19:dd:d9:dd:c25:c25:94de:93cf
2092c19:dd:d9:dd:c25:c25:94de:93d0/1282c19:dd:d9:dd:c25:c25:94de:93d0
2102c19:dd:d9:dd:c25:c25:94de:93d1/1282c19:dd:d9:dd:c25:c25:94de:93d1
2112c19:dd:d9:dd:c25:c25:94de:93d2/1282c19:dd:d9:dd:c25:c25:94de:93d2
2122c19:dd:d9:dd:c25:c25:94de:93d3/1282c19:dd:d9:dd:c25:c25:94de:93d3
2132c19:dd:d9:dd:c25:c25:94de:93d4/1282c19:dd:d9:dd:c25:c25:94de:93d4
2142c19:dd:d9:dd:c25:c25:94de:93d5/1282c19:dd:d9:dd:c25:c25:94de:93d5
2152c19:dd:d9:dd:c25:c25:94de:93d6/1282c19:dd:d9:dd:c25:c25:94de:93d6
2162c19:dd:d9:dd:c25:c25:94de:93d7/1282c19:dd:d9:dd:c25:c25:94de:93d7
2172c19:dd:d9:dd:c25:c25:94de:93d8/1282c19:dd:d9:dd:c25:c25:94de:93d8
2182c19:dd:d9:dd:c25:c25:94de:93d9/1282c19:dd:d9:dd:c25:c25:94de:93d9
2192c19:dd:d9:dd:c25:c25:94de:93da/1282c19:dd:d9:dd:c25:c25:94de:93da
2202c19:dd:d9:dd:c25:c25:94de:93db/1282c19:dd:d9:dd:c25:c25:94de:93db
2212c19:dd:d9:dd:c25:c25:94de:93dc/1282c19:dd:d9:dd:c25:c25:94de:93dc
2222c19:dd:d9:dd:c25:c25:94de:93dd/1282c19:dd:d9:dd:c25:c25:94de:93dd
2232c19:dd:d9:dd:c25:c25:94de:93de/1282c19:dd:d9:dd:c25:c25:94de:93de
2242c19:dd:d9:dd:c25:c25:94de:93df/1282c19:dd:d9:dd:c25:c25:94de:93df
2252c19:dd:d9:dd:c25:c25:94de:93e0/1282c19:dd:d9:dd:c25:c25:94de:93e0
2262c19:dd:d9:dd:c25:c25:94de:93e1/1282c19:dd:d9:dd:c25:c25:94de:93e1
2272c19:dd:d9:dd:c25:c25:94de:93e2/1282c19:dd:d9:dd:c25:c25:94de:93e2
2282c19:dd:d9:dd:c25:c25:94de:93e3/1282c19:dd:d9:dd:c25:c25:94de:93e3
2292c19:dd:d9:dd:c25:c25:94de:93e4/1282c19:dd:d9:dd:c25:c25:94de:93e4
2302c19:dd:d9:dd:c25:c25:94de:93e5/1282c19:dd:d9:dd:c25:c25:94de:93e5
2312c19:dd:d9:dd:c25:c25:94de:93e6/1282c19:dd:d9:dd:c25:c25:94de:93e6
2322c19:dd:d9:dd:c25:c25:94de:93e7/1282c19:dd:d9:dd:c25:c25:94de:93e7
2332c19:dd:d9:dd:c25:c25:94de:93e8/1282c19:dd:d9:dd:c25:c25:94de:93e8
2342c19:dd:d9:dd:c25:c25:94de:93e9/1282c19:dd:d9:dd:c25:c25:94de:93e9
2352c19:dd:d9:dd:c25:c25:94de:93ea/1282c19:dd:d9:dd:c25:c25:94de:93ea
2362c19:dd:d9:dd:c25:c25:94de:93eb/1282c19:dd:d9:dd:c25:c25:94de:93eb
2372c19:dd:d9:dd:c25:c25:94de:93ec/1282c19:dd:d9:dd:c25:c25:94de:93ec
2382c19:dd:d9:dd:c25:c25:94de:93ed/1282c19:dd:d9:dd:c25:c25:94de:93ed
2392c19:dd:d9:dd:c25:c25:94de:93ee/1282c19:dd:d9:dd:c25:c25:94de:93ee
2402c19:dd:d9:dd:c25:c25:94de:93ef/1282c19:dd:d9:dd:c25:c25:94de:93ef
2412c19:dd:d9:dd:c25:c25:94de:93f0/1282c19:dd:d9:dd:c25:c25:94de:93f0
2422c19:dd:d9:dd:c25:c25:94de:93f1/1282c19:dd:d9:dd:c25:c25:94de:93f1
2432c19:dd:d9:dd:c25:c25:94de:93f2/1282c19:dd:d9:dd:c25:c25:94de:93f2
2442c19:dd:d9:dd:c25:c25:94de:93f3/1282c19:dd:d9:dd:c25:c25:94de:93f3
2452c19:dd:d9:dd:c25:c25:94de:93f4/1282c19:dd:d9:dd:c25:c25:94de:93f4
2462c19:dd:d9:dd:c25:c25:94de:93f5/1282c19:dd:d9:dd:c25:c25:94de:93f5
2472c19:dd:d9:dd:c25:c25:94de:93f6/1282c19:dd:d9:dd:c25:c25:94de:93f6
2482c19:dd:d9:dd:c25:c25:94de:93f7/1282c19:dd:d9:dd:c25:c25:94de:93f7
2492c19:dd:d9:dd:c25:c25:94de:93f8/1282c19:dd:d9:dd:c25:c25:94de:93f8
2502c19:dd:d9:dd:c25:c25:94de:93f9/1282c19:dd:d9:dd:c25:c25:94de:93f9
2512c19:dd:d9:dd:c25:c25:94de:93fa/1282c19:dd:d9:dd:c25:c25:94de:93fa
2522c19:dd:d9:dd:c25:c25:94de:93fb/1282c19:dd:d9:dd:c25:c25:94de:93fb
2532c19:dd:d9:dd:c25:c25:94de:93fc/1282c19:dd:d9:dd:c25:c25:94de:93fc
2542c19:dd:d9:dd:c25:c25:94de:93fd/1282c19:dd:d9:dd:c25:c25:94de:93fd
2552c19:dd:d9:dd:c25:c25:94de:93fe/1282c19:dd:d9:dd:c25:c25:94de:93fe
2562c19:dd:d9:dd:c25:c25:94de:93ff/1282c19:dd:d9:dd:c25:c25:94de:93ff

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.