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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:8400/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:8400
Last address
2c19:dd:d9:dd:c25:c25a:d00a:84ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:8400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.8.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:8400/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:8400/1282c19:dd:d9:dd:c25:c25a:d00a:8400
22c19:dd:d9:dd:c25:c25a:d00a:8401/1282c19:dd:d9:dd:c25:c25a:d00a:8401
32c19:dd:d9:dd:c25:c25a:d00a:8402/1282c19:dd:d9:dd:c25:c25a:d00a:8402
42c19:dd:d9:dd:c25:c25a:d00a:8403/1282c19:dd:d9:dd:c25:c25a:d00a:8403
52c19:dd:d9:dd:c25:c25a:d00a:8404/1282c19:dd:d9:dd:c25:c25a:d00a:8404
62c19:dd:d9:dd:c25:c25a:d00a:8405/1282c19:dd:d9:dd:c25:c25a:d00a:8405
72c19:dd:d9:dd:c25:c25a:d00a:8406/1282c19:dd:d9:dd:c25:c25a:d00a:8406
82c19:dd:d9:dd:c25:c25a:d00a:8407/1282c19:dd:d9:dd:c25:c25a:d00a:8407
92c19:dd:d9:dd:c25:c25a:d00a:8408/1282c19:dd:d9:dd:c25:c25a:d00a:8408
102c19:dd:d9:dd:c25:c25a:d00a:8409/1282c19:dd:d9:dd:c25:c25a:d00a:8409
112c19:dd:d9:dd:c25:c25a:d00a:840a/1282c19:dd:d9:dd:c25:c25a:d00a:840a
122c19:dd:d9:dd:c25:c25a:d00a:840b/1282c19:dd:d9:dd:c25:c25a:d00a:840b
132c19:dd:d9:dd:c25:c25a:d00a:840c/1282c19:dd:d9:dd:c25:c25a:d00a:840c
142c19:dd:d9:dd:c25:c25a:d00a:840d/1282c19:dd:d9:dd:c25:c25a:d00a:840d
152c19:dd:d9:dd:c25:c25a:d00a:840e/1282c19:dd:d9:dd:c25:c25a:d00a:840e
162c19:dd:d9:dd:c25:c25a:d00a:840f/1282c19:dd:d9:dd:c25:c25a:d00a:840f
172c19:dd:d9:dd:c25:c25a:d00a:8410/1282c19:dd:d9:dd:c25:c25a:d00a:8410
182c19:dd:d9:dd:c25:c25a:d00a:8411/1282c19:dd:d9:dd:c25:c25a:d00a:8411
192c19:dd:d9:dd:c25:c25a:d00a:8412/1282c19:dd:d9:dd:c25:c25a:d00a:8412
202c19:dd:d9:dd:c25:c25a:d00a:8413/1282c19:dd:d9:dd:c25:c25a:d00a:8413
212c19:dd:d9:dd:c25:c25a:d00a:8414/1282c19:dd:d9:dd:c25:c25a:d00a:8414
222c19:dd:d9:dd:c25:c25a:d00a:8415/1282c19:dd:d9:dd:c25:c25a:d00a:8415
232c19:dd:d9:dd:c25:c25a:d00a:8416/1282c19:dd:d9:dd:c25:c25a:d00a:8416
242c19:dd:d9:dd:c25:c25a:d00a:8417/1282c19:dd:d9:dd:c25:c25a:d00a:8417
252c19:dd:d9:dd:c25:c25a:d00a:8418/1282c19:dd:d9:dd:c25:c25a:d00a:8418
262c19:dd:d9:dd:c25:c25a:d00a:8419/1282c19:dd:d9:dd:c25:c25a:d00a:8419
272c19:dd:d9:dd:c25:c25a:d00a:841a/1282c19:dd:d9:dd:c25:c25a:d00a:841a
282c19:dd:d9:dd:c25:c25a:d00a:841b/1282c19:dd:d9:dd:c25:c25a:d00a:841b
292c19:dd:d9:dd:c25:c25a:d00a:841c/1282c19:dd:d9:dd:c25:c25a:d00a:841c
302c19:dd:d9:dd:c25:c25a:d00a:841d/1282c19:dd:d9:dd:c25:c25a:d00a:841d
312c19:dd:d9:dd:c25:c25a:d00a:841e/1282c19:dd:d9:dd:c25:c25a:d00a:841e
322c19:dd:d9:dd:c25:c25a:d00a:841f/1282c19:dd:d9:dd:c25:c25a:d00a:841f
332c19:dd:d9:dd:c25:c25a:d00a:8420/1282c19:dd:d9:dd:c25:c25a:d00a:8420
342c19:dd:d9:dd:c25:c25a:d00a:8421/1282c19:dd:d9:dd:c25:c25a:d00a:8421
352c19:dd:d9:dd:c25:c25a:d00a:8422/1282c19:dd:d9:dd:c25:c25a:d00a:8422
362c19:dd:d9:dd:c25:c25a:d00a:8423/1282c19:dd:d9:dd:c25:c25a:d00a:8423
372c19:dd:d9:dd:c25:c25a:d00a:8424/1282c19:dd:d9:dd:c25:c25a:d00a:8424
382c19:dd:d9:dd:c25:c25a:d00a:8425/1282c19:dd:d9:dd:c25:c25a:d00a:8425
392c19:dd:d9:dd:c25:c25a:d00a:8426/1282c19:dd:d9:dd:c25:c25a:d00a:8426
402c19:dd:d9:dd:c25:c25a:d00a:8427/1282c19:dd:d9:dd:c25:c25a:d00a:8427
412c19:dd:d9:dd:c25:c25a:d00a:8428/1282c19:dd:d9:dd:c25:c25a:d00a:8428
422c19:dd:d9:dd:c25:c25a:d00a:8429/1282c19:dd:d9:dd:c25:c25a:d00a:8429
432c19:dd:d9:dd:c25:c25a:d00a:842a/1282c19:dd:d9:dd:c25:c25a:d00a:842a
442c19:dd:d9:dd:c25:c25a:d00a:842b/1282c19:dd:d9:dd:c25:c25a:d00a:842b
452c19:dd:d9:dd:c25:c25a:d00a:842c/1282c19:dd:d9:dd:c25:c25a:d00a:842c
462c19:dd:d9:dd:c25:c25a:d00a:842d/1282c19:dd:d9:dd:c25:c25a:d00a:842d
472c19:dd:d9:dd:c25:c25a:d00a:842e/1282c19:dd:d9:dd:c25:c25a:d00a:842e
482c19:dd:d9:dd:c25:c25a:d00a:842f/1282c19:dd:d9:dd:c25:c25a:d00a:842f
492c19:dd:d9:dd:c25:c25a:d00a:8430/1282c19:dd:d9:dd:c25:c25a:d00a:8430
502c19:dd:d9:dd:c25:c25a:d00a:8431/1282c19:dd:d9:dd:c25:c25a:d00a:8431
512c19:dd:d9:dd:c25:c25a:d00a:8432/1282c19:dd:d9:dd:c25:c25a:d00a:8432
522c19:dd:d9:dd:c25:c25a:d00a:8433/1282c19:dd:d9:dd:c25:c25a:d00a:8433
532c19:dd:d9:dd:c25:c25a:d00a:8434/1282c19:dd:d9:dd:c25:c25a:d00a:8434
542c19:dd:d9:dd:c25:c25a:d00a:8435/1282c19:dd:d9:dd:c25:c25a:d00a:8435
552c19:dd:d9:dd:c25:c25a:d00a:8436/1282c19:dd:d9:dd:c25:c25a:d00a:8436
562c19:dd:d9:dd:c25:c25a:d00a:8437/1282c19:dd:d9:dd:c25:c25a:d00a:8437
572c19:dd:d9:dd:c25:c25a:d00a:8438/1282c19:dd:d9:dd:c25:c25a:d00a:8438
582c19:dd:d9:dd:c25:c25a:d00a:8439/1282c19:dd:d9:dd:c25:c25a:d00a:8439
592c19:dd:d9:dd:c25:c25a:d00a:843a/1282c19:dd:d9:dd:c25:c25a:d00a:843a
602c19:dd:d9:dd:c25:c25a:d00a:843b/1282c19:dd:d9:dd:c25:c25a:d00a:843b
612c19:dd:d9:dd:c25:c25a:d00a:843c/1282c19:dd:d9:dd:c25:c25a:d00a:843c
622c19:dd:d9:dd:c25:c25a:d00a:843d/1282c19:dd:d9:dd:c25:c25a:d00a:843d
632c19:dd:d9:dd:c25:c25a:d00a:843e/1282c19:dd:d9:dd:c25:c25a:d00a:843e
642c19:dd:d9:dd:c25:c25a:d00a:843f/1282c19:dd:d9:dd:c25:c25a:d00a:843f
652c19:dd:d9:dd:c25:c25a:d00a:8440/1282c19:dd:d9:dd:c25:c25a:d00a:8440
662c19:dd:d9:dd:c25:c25a:d00a:8441/1282c19:dd:d9:dd:c25:c25a:d00a:8441
672c19:dd:d9:dd:c25:c25a:d00a:8442/1282c19:dd:d9:dd:c25:c25a:d00a:8442
682c19:dd:d9:dd:c25:c25a:d00a:8443/1282c19:dd:d9:dd:c25:c25a:d00a:8443
692c19:dd:d9:dd:c25:c25a:d00a:8444/1282c19:dd:d9:dd:c25:c25a:d00a:8444
702c19:dd:d9:dd:c25:c25a:d00a:8445/1282c19:dd:d9:dd:c25:c25a:d00a:8445
712c19:dd:d9:dd:c25:c25a:d00a:8446/1282c19:dd:d9:dd:c25:c25a:d00a:8446
722c19:dd:d9:dd:c25:c25a:d00a:8447/1282c19:dd:d9:dd:c25:c25a:d00a:8447
732c19:dd:d9:dd:c25:c25a:d00a:8448/1282c19:dd:d9:dd:c25:c25a:d00a:8448
742c19:dd:d9:dd:c25:c25a:d00a:8449/1282c19:dd:d9:dd:c25:c25a:d00a:8449
752c19:dd:d9:dd:c25:c25a:d00a:844a/1282c19:dd:d9:dd:c25:c25a:d00a:844a
762c19:dd:d9:dd:c25:c25a:d00a:844b/1282c19:dd:d9:dd:c25:c25a:d00a:844b
772c19:dd:d9:dd:c25:c25a:d00a:844c/1282c19:dd:d9:dd:c25:c25a:d00a:844c
782c19:dd:d9:dd:c25:c25a:d00a:844d/1282c19:dd:d9:dd:c25:c25a:d00a:844d
792c19:dd:d9:dd:c25:c25a:d00a:844e/1282c19:dd:d9:dd:c25:c25a:d00a:844e
802c19:dd:d9:dd:c25:c25a:d00a:844f/1282c19:dd:d9:dd:c25:c25a:d00a:844f
812c19:dd:d9:dd:c25:c25a:d00a:8450/1282c19:dd:d9:dd:c25:c25a:d00a:8450
822c19:dd:d9:dd:c25:c25a:d00a:8451/1282c19:dd:d9:dd:c25:c25a:d00a:8451
832c19:dd:d9:dd:c25:c25a:d00a:8452/1282c19:dd:d9:dd:c25:c25a:d00a:8452
842c19:dd:d9:dd:c25:c25a:d00a:8453/1282c19:dd:d9:dd:c25:c25a:d00a:8453
852c19:dd:d9:dd:c25:c25a:d00a:8454/1282c19:dd:d9:dd:c25:c25a:d00a:8454
862c19:dd:d9:dd:c25:c25a:d00a:8455/1282c19:dd:d9:dd:c25:c25a:d00a:8455
872c19:dd:d9:dd:c25:c25a:d00a:8456/1282c19:dd:d9:dd:c25:c25a:d00a:8456
882c19:dd:d9:dd:c25:c25a:d00a:8457/1282c19:dd:d9:dd:c25:c25a:d00a:8457
892c19:dd:d9:dd:c25:c25a:d00a:8458/1282c19:dd:d9:dd:c25:c25a:d00a:8458
902c19:dd:d9:dd:c25:c25a:d00a:8459/1282c19:dd:d9:dd:c25:c25a:d00a:8459
912c19:dd:d9:dd:c25:c25a:d00a:845a/1282c19:dd:d9:dd:c25:c25a:d00a:845a
922c19:dd:d9:dd:c25:c25a:d00a:845b/1282c19:dd:d9:dd:c25:c25a:d00a:845b
932c19:dd:d9:dd:c25:c25a:d00a:845c/1282c19:dd:d9:dd:c25:c25a:d00a:845c
942c19:dd:d9:dd:c25:c25a:d00a:845d/1282c19:dd:d9:dd:c25:c25a:d00a:845d
952c19:dd:d9:dd:c25:c25a:d00a:845e/1282c19:dd:d9:dd:c25:c25a:d00a:845e
962c19:dd:d9:dd:c25:c25a:d00a:845f/1282c19:dd:d9:dd:c25:c25a:d00a:845f
972c19:dd:d9:dd:c25:c25a:d00a:8460/1282c19:dd:d9:dd:c25:c25a:d00a:8460
982c19:dd:d9:dd:c25:c25a:d00a:8461/1282c19:dd:d9:dd:c25:c25a:d00a:8461
992c19:dd:d9:dd:c25:c25a:d00a:8462/1282c19:dd:d9:dd:c25:c25a:d00a:8462
1002c19:dd:d9:dd:c25:c25a:d00a:8463/1282c19:dd:d9:dd:c25:c25a:d00a:8463
1012c19:dd:d9:dd:c25:c25a:d00a:8464/1282c19:dd:d9:dd:c25:c25a:d00a:8464
1022c19:dd:d9:dd:c25:c25a:d00a:8465/1282c19:dd:d9:dd:c25:c25a:d00a:8465
1032c19:dd:d9:dd:c25:c25a:d00a:8466/1282c19:dd:d9:dd:c25:c25a:d00a:8466
1042c19:dd:d9:dd:c25:c25a:d00a:8467/1282c19:dd:d9:dd:c25:c25a:d00a:8467
1052c19:dd:d9:dd:c25:c25a:d00a:8468/1282c19:dd:d9:dd:c25:c25a:d00a:8468
1062c19:dd:d9:dd:c25:c25a:d00a:8469/1282c19:dd:d9:dd:c25:c25a:d00a:8469
1072c19:dd:d9:dd:c25:c25a:d00a:846a/1282c19:dd:d9:dd:c25:c25a:d00a:846a
1082c19:dd:d9:dd:c25:c25a:d00a:846b/1282c19:dd:d9:dd:c25:c25a:d00a:846b
1092c19:dd:d9:dd:c25:c25a:d00a:846c/1282c19:dd:d9:dd:c25:c25a:d00a:846c
1102c19:dd:d9:dd:c25:c25a:d00a:846d/1282c19:dd:d9:dd:c25:c25a:d00a:846d
1112c19:dd:d9:dd:c25:c25a:d00a:846e/1282c19:dd:d9:dd:c25:c25a:d00a:846e
1122c19:dd:d9:dd:c25:c25a:d00a:846f/1282c19:dd:d9:dd:c25:c25a:d00a:846f
1132c19:dd:d9:dd:c25:c25a:d00a:8470/1282c19:dd:d9:dd:c25:c25a:d00a:8470
1142c19:dd:d9:dd:c25:c25a:d00a:8471/1282c19:dd:d9:dd:c25:c25a:d00a:8471
1152c19:dd:d9:dd:c25:c25a:d00a:8472/1282c19:dd:d9:dd:c25:c25a:d00a:8472
1162c19:dd:d9:dd:c25:c25a:d00a:8473/1282c19:dd:d9:dd:c25:c25a:d00a:8473
1172c19:dd:d9:dd:c25:c25a:d00a:8474/1282c19:dd:d9:dd:c25:c25a:d00a:8474
1182c19:dd:d9:dd:c25:c25a:d00a:8475/1282c19:dd:d9:dd:c25:c25a:d00a:8475
1192c19:dd:d9:dd:c25:c25a:d00a:8476/1282c19:dd:d9:dd:c25:c25a:d00a:8476
1202c19:dd:d9:dd:c25:c25a:d00a:8477/1282c19:dd:d9:dd:c25:c25a:d00a:8477
1212c19:dd:d9:dd:c25:c25a:d00a:8478/1282c19:dd:d9:dd:c25:c25a:d00a:8478
1222c19:dd:d9:dd:c25:c25a:d00a:8479/1282c19:dd:d9:dd:c25:c25a:d00a:8479
1232c19:dd:d9:dd:c25:c25a:d00a:847a/1282c19:dd:d9:dd:c25:c25a:d00a:847a
1242c19:dd:d9:dd:c25:c25a:d00a:847b/1282c19:dd:d9:dd:c25:c25a:d00a:847b
1252c19:dd:d9:dd:c25:c25a:d00a:847c/1282c19:dd:d9:dd:c25:c25a:d00a:847c
1262c19:dd:d9:dd:c25:c25a:d00a:847d/1282c19:dd:d9:dd:c25:c25a:d00a:847d
1272c19:dd:d9:dd:c25:c25a:d00a:847e/1282c19:dd:d9:dd:c25:c25a:d00a:847e
1282c19:dd:d9:dd:c25:c25a:d00a:847f/1282c19:dd:d9:dd:c25:c25a:d00a:847f
1292c19:dd:d9:dd:c25:c25a:d00a:8480/1282c19:dd:d9:dd:c25:c25a:d00a:8480
1302c19:dd:d9:dd:c25:c25a:d00a:8481/1282c19:dd:d9:dd:c25:c25a:d00a:8481
1312c19:dd:d9:dd:c25:c25a:d00a:8482/1282c19:dd:d9:dd:c25:c25a:d00a:8482
1322c19:dd:d9:dd:c25:c25a:d00a:8483/1282c19:dd:d9:dd:c25:c25a:d00a:8483
1332c19:dd:d9:dd:c25:c25a:d00a:8484/1282c19:dd:d9:dd:c25:c25a:d00a:8484
1342c19:dd:d9:dd:c25:c25a:d00a:8485/1282c19:dd:d9:dd:c25:c25a:d00a:8485
1352c19:dd:d9:dd:c25:c25a:d00a:8486/1282c19:dd:d9:dd:c25:c25a:d00a:8486
1362c19:dd:d9:dd:c25:c25a:d00a:8487/1282c19:dd:d9:dd:c25:c25a:d00a:8487
1372c19:dd:d9:dd:c25:c25a:d00a:8488/1282c19:dd:d9:dd:c25:c25a:d00a:8488
1382c19:dd:d9:dd:c25:c25a:d00a:8489/1282c19:dd:d9:dd:c25:c25a:d00a:8489
1392c19:dd:d9:dd:c25:c25a:d00a:848a/1282c19:dd:d9:dd:c25:c25a:d00a:848a
1402c19:dd:d9:dd:c25:c25a:d00a:848b/1282c19:dd:d9:dd:c25:c25a:d00a:848b
1412c19:dd:d9:dd:c25:c25a:d00a:848c/1282c19:dd:d9:dd:c25:c25a:d00a:848c
1422c19:dd:d9:dd:c25:c25a:d00a:848d/1282c19:dd:d9:dd:c25:c25a:d00a:848d
1432c19:dd:d9:dd:c25:c25a:d00a:848e/1282c19:dd:d9:dd:c25:c25a:d00a:848e
1442c19:dd:d9:dd:c25:c25a:d00a:848f/1282c19:dd:d9:dd:c25:c25a:d00a:848f
1452c19:dd:d9:dd:c25:c25a:d00a:8490/1282c19:dd:d9:dd:c25:c25a:d00a:8490
1462c19:dd:d9:dd:c25:c25a:d00a:8491/1282c19:dd:d9:dd:c25:c25a:d00a:8491
1472c19:dd:d9:dd:c25:c25a:d00a:8492/1282c19:dd:d9:dd:c25:c25a:d00a:8492
1482c19:dd:d9:dd:c25:c25a:d00a:8493/1282c19:dd:d9:dd:c25:c25a:d00a:8493
1492c19:dd:d9:dd:c25:c25a:d00a:8494/1282c19:dd:d9:dd:c25:c25a:d00a:8494
1502c19:dd:d9:dd:c25:c25a:d00a:8495/1282c19:dd:d9:dd:c25:c25a:d00a:8495
1512c19:dd:d9:dd:c25:c25a:d00a:8496/1282c19:dd:d9:dd:c25:c25a:d00a:8496
1522c19:dd:d9:dd:c25:c25a:d00a:8497/1282c19:dd:d9:dd:c25:c25a:d00a:8497
1532c19:dd:d9:dd:c25:c25a:d00a:8498/1282c19:dd:d9:dd:c25:c25a:d00a:8498
1542c19:dd:d9:dd:c25:c25a:d00a:8499/1282c19:dd:d9:dd:c25:c25a:d00a:8499
1552c19:dd:d9:dd:c25:c25a:d00a:849a/1282c19:dd:d9:dd:c25:c25a:d00a:849a
1562c19:dd:d9:dd:c25:c25a:d00a:849b/1282c19:dd:d9:dd:c25:c25a:d00a:849b
1572c19:dd:d9:dd:c25:c25a:d00a:849c/1282c19:dd:d9:dd:c25:c25a:d00a:849c
1582c19:dd:d9:dd:c25:c25a:d00a:849d/1282c19:dd:d9:dd:c25:c25a:d00a:849d
1592c19:dd:d9:dd:c25:c25a:d00a:849e/1282c19:dd:d9:dd:c25:c25a:d00a:849e
1602c19:dd:d9:dd:c25:c25a:d00a:849f/1282c19:dd:d9:dd:c25:c25a:d00a:849f
1612c19:dd:d9:dd:c25:c25a:d00a:84a0/1282c19:dd:d9:dd:c25:c25a:d00a:84a0
1622c19:dd:d9:dd:c25:c25a:d00a:84a1/1282c19:dd:d9:dd:c25:c25a:d00a:84a1
1632c19:dd:d9:dd:c25:c25a:d00a:84a2/1282c19:dd:d9:dd:c25:c25a:d00a:84a2
1642c19:dd:d9:dd:c25:c25a:d00a:84a3/1282c19:dd:d9:dd:c25:c25a:d00a:84a3
1652c19:dd:d9:dd:c25:c25a:d00a:84a4/1282c19:dd:d9:dd:c25:c25a:d00a:84a4
1662c19:dd:d9:dd:c25:c25a:d00a:84a5/1282c19:dd:d9:dd:c25:c25a:d00a:84a5
1672c19:dd:d9:dd:c25:c25a:d00a:84a6/1282c19:dd:d9:dd:c25:c25a:d00a:84a6
1682c19:dd:d9:dd:c25:c25a:d00a:84a7/1282c19:dd:d9:dd:c25:c25a:d00a:84a7
1692c19:dd:d9:dd:c25:c25a:d00a:84a8/1282c19:dd:d9:dd:c25:c25a:d00a:84a8
1702c19:dd:d9:dd:c25:c25a:d00a:84a9/1282c19:dd:d9:dd:c25:c25a:d00a:84a9
1712c19:dd:d9:dd:c25:c25a:d00a:84aa/1282c19:dd:d9:dd:c25:c25a:d00a:84aa
1722c19:dd:d9:dd:c25:c25a:d00a:84ab/1282c19:dd:d9:dd:c25:c25a:d00a:84ab
1732c19:dd:d9:dd:c25:c25a:d00a:84ac/1282c19:dd:d9:dd:c25:c25a:d00a:84ac
1742c19:dd:d9:dd:c25:c25a:d00a:84ad/1282c19:dd:d9:dd:c25:c25a:d00a:84ad
1752c19:dd:d9:dd:c25:c25a:d00a:84ae/1282c19:dd:d9:dd:c25:c25a:d00a:84ae
1762c19:dd:d9:dd:c25:c25a:d00a:84af/1282c19:dd:d9:dd:c25:c25a:d00a:84af
1772c19:dd:d9:dd:c25:c25a:d00a:84b0/1282c19:dd:d9:dd:c25:c25a:d00a:84b0
1782c19:dd:d9:dd:c25:c25a:d00a:84b1/1282c19:dd:d9:dd:c25:c25a:d00a:84b1
1792c19:dd:d9:dd:c25:c25a:d00a:84b2/1282c19:dd:d9:dd:c25:c25a:d00a:84b2
1802c19:dd:d9:dd:c25:c25a:d00a:84b3/1282c19:dd:d9:dd:c25:c25a:d00a:84b3
1812c19:dd:d9:dd:c25:c25a:d00a:84b4/1282c19:dd:d9:dd:c25:c25a:d00a:84b4
1822c19:dd:d9:dd:c25:c25a:d00a:84b5/1282c19:dd:d9:dd:c25:c25a:d00a:84b5
1832c19:dd:d9:dd:c25:c25a:d00a:84b6/1282c19:dd:d9:dd:c25:c25a:d00a:84b6
1842c19:dd:d9:dd:c25:c25a:d00a:84b7/1282c19:dd:d9:dd:c25:c25a:d00a:84b7
1852c19:dd:d9:dd:c25:c25a:d00a:84b8/1282c19:dd:d9:dd:c25:c25a:d00a:84b8
1862c19:dd:d9:dd:c25:c25a:d00a:84b9/1282c19:dd:d9:dd:c25:c25a:d00a:84b9
1872c19:dd:d9:dd:c25:c25a:d00a:84ba/1282c19:dd:d9:dd:c25:c25a:d00a:84ba
1882c19:dd:d9:dd:c25:c25a:d00a:84bb/1282c19:dd:d9:dd:c25:c25a:d00a:84bb
1892c19:dd:d9:dd:c25:c25a:d00a:84bc/1282c19:dd:d9:dd:c25:c25a:d00a:84bc
1902c19:dd:d9:dd:c25:c25a:d00a:84bd/1282c19:dd:d9:dd:c25:c25a:d00a:84bd
1912c19:dd:d9:dd:c25:c25a:d00a:84be/1282c19:dd:d9:dd:c25:c25a:d00a:84be
1922c19:dd:d9:dd:c25:c25a:d00a:84bf/1282c19:dd:d9:dd:c25:c25a:d00a:84bf
1932c19:dd:d9:dd:c25:c25a:d00a:84c0/1282c19:dd:d9:dd:c25:c25a:d00a:84c0
1942c19:dd:d9:dd:c25:c25a:d00a:84c1/1282c19:dd:d9:dd:c25:c25a:d00a:84c1
1952c19:dd:d9:dd:c25:c25a:d00a:84c2/1282c19:dd:d9:dd:c25:c25a:d00a:84c2
1962c19:dd:d9:dd:c25:c25a:d00a:84c3/1282c19:dd:d9:dd:c25:c25a:d00a:84c3
1972c19:dd:d9:dd:c25:c25a:d00a:84c4/1282c19:dd:d9:dd:c25:c25a:d00a:84c4
1982c19:dd:d9:dd:c25:c25a:d00a:84c5/1282c19:dd:d9:dd:c25:c25a:d00a:84c5
1992c19:dd:d9:dd:c25:c25a:d00a:84c6/1282c19:dd:d9:dd:c25:c25a:d00a:84c6
2002c19:dd:d9:dd:c25:c25a:d00a:84c7/1282c19:dd:d9:dd:c25:c25a:d00a:84c7
2012c19:dd:d9:dd:c25:c25a:d00a:84c8/1282c19:dd:d9:dd:c25:c25a:d00a:84c8
2022c19:dd:d9:dd:c25:c25a:d00a:84c9/1282c19:dd:d9:dd:c25:c25a:d00a:84c9
2032c19:dd:d9:dd:c25:c25a:d00a:84ca/1282c19:dd:d9:dd:c25:c25a:d00a:84ca
2042c19:dd:d9:dd:c25:c25a:d00a:84cb/1282c19:dd:d9:dd:c25:c25a:d00a:84cb
2052c19:dd:d9:dd:c25:c25a:d00a:84cc/1282c19:dd:d9:dd:c25:c25a:d00a:84cc
2062c19:dd:d9:dd:c25:c25a:d00a:84cd/1282c19:dd:d9:dd:c25:c25a:d00a:84cd
2072c19:dd:d9:dd:c25:c25a:d00a:84ce/1282c19:dd:d9:dd:c25:c25a:d00a:84ce
2082c19:dd:d9:dd:c25:c25a:d00a:84cf/1282c19:dd:d9:dd:c25:c25a:d00a:84cf
2092c19:dd:d9:dd:c25:c25a:d00a:84d0/1282c19:dd:d9:dd:c25:c25a:d00a:84d0
2102c19:dd:d9:dd:c25:c25a:d00a:84d1/1282c19:dd:d9:dd:c25:c25a:d00a:84d1
2112c19:dd:d9:dd:c25:c25a:d00a:84d2/1282c19:dd:d9:dd:c25:c25a:d00a:84d2
2122c19:dd:d9:dd:c25:c25a:d00a:84d3/1282c19:dd:d9:dd:c25:c25a:d00a:84d3
2132c19:dd:d9:dd:c25:c25a:d00a:84d4/1282c19:dd:d9:dd:c25:c25a:d00a:84d4
2142c19:dd:d9:dd:c25:c25a:d00a:84d5/1282c19:dd:d9:dd:c25:c25a:d00a:84d5
2152c19:dd:d9:dd:c25:c25a:d00a:84d6/1282c19:dd:d9:dd:c25:c25a:d00a:84d6
2162c19:dd:d9:dd:c25:c25a:d00a:84d7/1282c19:dd:d9:dd:c25:c25a:d00a:84d7
2172c19:dd:d9:dd:c25:c25a:d00a:84d8/1282c19:dd:d9:dd:c25:c25a:d00a:84d8
2182c19:dd:d9:dd:c25:c25a:d00a:84d9/1282c19:dd:d9:dd:c25:c25a:d00a:84d9
2192c19:dd:d9:dd:c25:c25a:d00a:84da/1282c19:dd:d9:dd:c25:c25a:d00a:84da
2202c19:dd:d9:dd:c25:c25a:d00a:84db/1282c19:dd:d9:dd:c25:c25a:d00a:84db
2212c19:dd:d9:dd:c25:c25a:d00a:84dc/1282c19:dd:d9:dd:c25:c25a:d00a:84dc
2222c19:dd:d9:dd:c25:c25a:d00a:84dd/1282c19:dd:d9:dd:c25:c25a:d00a:84dd
2232c19:dd:d9:dd:c25:c25a:d00a:84de/1282c19:dd:d9:dd:c25:c25a:d00a:84de
2242c19:dd:d9:dd:c25:c25a:d00a:84df/1282c19:dd:d9:dd:c25:c25a:d00a:84df
2252c19:dd:d9:dd:c25:c25a:d00a:84e0/1282c19:dd:d9:dd:c25:c25a:d00a:84e0
2262c19:dd:d9:dd:c25:c25a:d00a:84e1/1282c19:dd:d9:dd:c25:c25a:d00a:84e1
2272c19:dd:d9:dd:c25:c25a:d00a:84e2/1282c19:dd:d9:dd:c25:c25a:d00a:84e2
2282c19:dd:d9:dd:c25:c25a:d00a:84e3/1282c19:dd:d9:dd:c25:c25a:d00a:84e3
2292c19:dd:d9:dd:c25:c25a:d00a:84e4/1282c19:dd:d9:dd:c25:c25a:d00a:84e4
2302c19:dd:d9:dd:c25:c25a:d00a:84e5/1282c19:dd:d9:dd:c25:c25a:d00a:84e5
2312c19:dd:d9:dd:c25:c25a:d00a:84e6/1282c19:dd:d9:dd:c25:c25a:d00a:84e6
2322c19:dd:d9:dd:c25:c25a:d00a:84e7/1282c19:dd:d9:dd:c25:c25a:d00a:84e7
2332c19:dd:d9:dd:c25:c25a:d00a:84e8/1282c19:dd:d9:dd:c25:c25a:d00a:84e8
2342c19:dd:d9:dd:c25:c25a:d00a:84e9/1282c19:dd:d9:dd:c25:c25a:d00a:84e9
2352c19:dd:d9:dd:c25:c25a:d00a:84ea/1282c19:dd:d9:dd:c25:c25a:d00a:84ea
2362c19:dd:d9:dd:c25:c25a:d00a:84eb/1282c19:dd:d9:dd:c25:c25a:d00a:84eb
2372c19:dd:d9:dd:c25:c25a:d00a:84ec/1282c19:dd:d9:dd:c25:c25a:d00a:84ec
2382c19:dd:d9:dd:c25:c25a:d00a:84ed/1282c19:dd:d9:dd:c25:c25a:d00a:84ed
2392c19:dd:d9:dd:c25:c25a:d00a:84ee/1282c19:dd:d9:dd:c25:c25a:d00a:84ee
2402c19:dd:d9:dd:c25:c25a:d00a:84ef/1282c19:dd:d9:dd:c25:c25a:d00a:84ef
2412c19:dd:d9:dd:c25:c25a:d00a:84f0/1282c19:dd:d9:dd:c25:c25a:d00a:84f0
2422c19:dd:d9:dd:c25:c25a:d00a:84f1/1282c19:dd:d9:dd:c25:c25a:d00a:84f1
2432c19:dd:d9:dd:c25:c25a:d00a:84f2/1282c19:dd:d9:dd:c25:c25a:d00a:84f2
2442c19:dd:d9:dd:c25:c25a:d00a:84f3/1282c19:dd:d9:dd:c25:c25a:d00a:84f3
2452c19:dd:d9:dd:c25:c25a:d00a:84f4/1282c19:dd:d9:dd:c25:c25a:d00a:84f4
2462c19:dd:d9:dd:c25:c25a:d00a:84f5/1282c19:dd:d9:dd:c25:c25a:d00a:84f5
2472c19:dd:d9:dd:c25:c25a:d00a:84f6/1282c19:dd:d9:dd:c25:c25a:d00a:84f6
2482c19:dd:d9:dd:c25:c25a:d00a:84f7/1282c19:dd:d9:dd:c25:c25a:d00a:84f7
2492c19:dd:d9:dd:c25:c25a:d00a:84f8/1282c19:dd:d9:dd:c25:c25a:d00a:84f8
2502c19:dd:d9:dd:c25:c25a:d00a:84f9/1282c19:dd:d9:dd:c25:c25a:d00a:84f9
2512c19:dd:d9:dd:c25:c25a:d00a:84fa/1282c19:dd:d9:dd:c25:c25a:d00a:84fa
2522c19:dd:d9:dd:c25:c25a:d00a:84fb/1282c19:dd:d9:dd:c25:c25a:d00a:84fb
2532c19:dd:d9:dd:c25:c25a:d00a:84fc/1282c19:dd:d9:dd:c25:c25a:d00a:84fc
2542c19:dd:d9:dd:c25:c25a:d00a:84fd/1282c19:dd:d9:dd:c25:c25a:d00a:84fd
2552c19:dd:d9:dd:c25:c25a:d00a:84fe/1282c19:dd:d9:dd:c25:c25a:d00a:84fe
2562c19:dd:d9:dd:c25:c25a:d00a:84ff/1282c19:dd:d9:dd:c25:c25a:d00a:84ff

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.