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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:c25:c25f:dd4e:dd:dd:7400/120
First address
2c19:dd:c25:c25f:dd4e:dd:dd:7400
Last address
2c19:dd:c25:c25f:dd4e:dd:dd:74ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25f:dd4e:00dd:00dd:7400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.7.d.d.0.0.d.d.0.0.e.4.d.d.f.5.2.c.5.2.c.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:c25:c25f:dd4e:dd:dd:7400/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:c25:c25f:dd4e:dd:dd:7400/1282c19:dd:c25:c25f:dd4e:dd:dd:7400
22c19:dd:c25:c25f:dd4e:dd:dd:7401/1282c19:dd:c25:c25f:dd4e:dd:dd:7401
32c19:dd:c25:c25f:dd4e:dd:dd:7402/1282c19:dd:c25:c25f:dd4e:dd:dd:7402
42c19:dd:c25:c25f:dd4e:dd:dd:7403/1282c19:dd:c25:c25f:dd4e:dd:dd:7403
52c19:dd:c25:c25f:dd4e:dd:dd:7404/1282c19:dd:c25:c25f:dd4e:dd:dd:7404
62c19:dd:c25:c25f:dd4e:dd:dd:7405/1282c19:dd:c25:c25f:dd4e:dd:dd:7405
72c19:dd:c25:c25f:dd4e:dd:dd:7406/1282c19:dd:c25:c25f:dd4e:dd:dd:7406
82c19:dd:c25:c25f:dd4e:dd:dd:7407/1282c19:dd:c25:c25f:dd4e:dd:dd:7407
92c19:dd:c25:c25f:dd4e:dd:dd:7408/1282c19:dd:c25:c25f:dd4e:dd:dd:7408
102c19:dd:c25:c25f:dd4e:dd:dd:7409/1282c19:dd:c25:c25f:dd4e:dd:dd:7409
112c19:dd:c25:c25f:dd4e:dd:dd:740a/1282c19:dd:c25:c25f:dd4e:dd:dd:740a
122c19:dd:c25:c25f:dd4e:dd:dd:740b/1282c19:dd:c25:c25f:dd4e:dd:dd:740b
132c19:dd:c25:c25f:dd4e:dd:dd:740c/1282c19:dd:c25:c25f:dd4e:dd:dd:740c
142c19:dd:c25:c25f:dd4e:dd:dd:740d/1282c19:dd:c25:c25f:dd4e:dd:dd:740d
152c19:dd:c25:c25f:dd4e:dd:dd:740e/1282c19:dd:c25:c25f:dd4e:dd:dd:740e
162c19:dd:c25:c25f:dd4e:dd:dd:740f/1282c19:dd:c25:c25f:dd4e:dd:dd:740f
172c19:dd:c25:c25f:dd4e:dd:dd:7410/1282c19:dd:c25:c25f:dd4e:dd:dd:7410
182c19:dd:c25:c25f:dd4e:dd:dd:7411/1282c19:dd:c25:c25f:dd4e:dd:dd:7411
192c19:dd:c25:c25f:dd4e:dd:dd:7412/1282c19:dd:c25:c25f:dd4e:dd:dd:7412
202c19:dd:c25:c25f:dd4e:dd:dd:7413/1282c19:dd:c25:c25f:dd4e:dd:dd:7413
212c19:dd:c25:c25f:dd4e:dd:dd:7414/1282c19:dd:c25:c25f:dd4e:dd:dd:7414
222c19:dd:c25:c25f:dd4e:dd:dd:7415/1282c19:dd:c25:c25f:dd4e:dd:dd:7415
232c19:dd:c25:c25f:dd4e:dd:dd:7416/1282c19:dd:c25:c25f:dd4e:dd:dd:7416
242c19:dd:c25:c25f:dd4e:dd:dd:7417/1282c19:dd:c25:c25f:dd4e:dd:dd:7417
252c19:dd:c25:c25f:dd4e:dd:dd:7418/1282c19:dd:c25:c25f:dd4e:dd:dd:7418
262c19:dd:c25:c25f:dd4e:dd:dd:7419/1282c19:dd:c25:c25f:dd4e:dd:dd:7419
272c19:dd:c25:c25f:dd4e:dd:dd:741a/1282c19:dd:c25:c25f:dd4e:dd:dd:741a
282c19:dd:c25:c25f:dd4e:dd:dd:741b/1282c19:dd:c25:c25f:dd4e:dd:dd:741b
292c19:dd:c25:c25f:dd4e:dd:dd:741c/1282c19:dd:c25:c25f:dd4e:dd:dd:741c
302c19:dd:c25:c25f:dd4e:dd:dd:741d/1282c19:dd:c25:c25f:dd4e:dd:dd:741d
312c19:dd:c25:c25f:dd4e:dd:dd:741e/1282c19:dd:c25:c25f:dd4e:dd:dd:741e
322c19:dd:c25:c25f:dd4e:dd:dd:741f/1282c19:dd:c25:c25f:dd4e:dd:dd:741f
332c19:dd:c25:c25f:dd4e:dd:dd:7420/1282c19:dd:c25:c25f:dd4e:dd:dd:7420
342c19:dd:c25:c25f:dd4e:dd:dd:7421/1282c19:dd:c25:c25f:dd4e:dd:dd:7421
352c19:dd:c25:c25f:dd4e:dd:dd:7422/1282c19:dd:c25:c25f:dd4e:dd:dd:7422
362c19:dd:c25:c25f:dd4e:dd:dd:7423/1282c19:dd:c25:c25f:dd4e:dd:dd:7423
372c19:dd:c25:c25f:dd4e:dd:dd:7424/1282c19:dd:c25:c25f:dd4e:dd:dd:7424
382c19:dd:c25:c25f:dd4e:dd:dd:7425/1282c19:dd:c25:c25f:dd4e:dd:dd:7425
392c19:dd:c25:c25f:dd4e:dd:dd:7426/1282c19:dd:c25:c25f:dd4e:dd:dd:7426
402c19:dd:c25:c25f:dd4e:dd:dd:7427/1282c19:dd:c25:c25f:dd4e:dd:dd:7427
412c19:dd:c25:c25f:dd4e:dd:dd:7428/1282c19:dd:c25:c25f:dd4e:dd:dd:7428
422c19:dd:c25:c25f:dd4e:dd:dd:7429/1282c19:dd:c25:c25f:dd4e:dd:dd:7429
432c19:dd:c25:c25f:dd4e:dd:dd:742a/1282c19:dd:c25:c25f:dd4e:dd:dd:742a
442c19:dd:c25:c25f:dd4e:dd:dd:742b/1282c19:dd:c25:c25f:dd4e:dd:dd:742b
452c19:dd:c25:c25f:dd4e:dd:dd:742c/1282c19:dd:c25:c25f:dd4e:dd:dd:742c
462c19:dd:c25:c25f:dd4e:dd:dd:742d/1282c19:dd:c25:c25f:dd4e:dd:dd:742d
472c19:dd:c25:c25f:dd4e:dd:dd:742e/1282c19:dd:c25:c25f:dd4e:dd:dd:742e
482c19:dd:c25:c25f:dd4e:dd:dd:742f/1282c19:dd:c25:c25f:dd4e:dd:dd:742f
492c19:dd:c25:c25f:dd4e:dd:dd:7430/1282c19:dd:c25:c25f:dd4e:dd:dd:7430
502c19:dd:c25:c25f:dd4e:dd:dd:7431/1282c19:dd:c25:c25f:dd4e:dd:dd:7431
512c19:dd:c25:c25f:dd4e:dd:dd:7432/1282c19:dd:c25:c25f:dd4e:dd:dd:7432
522c19:dd:c25:c25f:dd4e:dd:dd:7433/1282c19:dd:c25:c25f:dd4e:dd:dd:7433
532c19:dd:c25:c25f:dd4e:dd:dd:7434/1282c19:dd:c25:c25f:dd4e:dd:dd:7434
542c19:dd:c25:c25f:dd4e:dd:dd:7435/1282c19:dd:c25:c25f:dd4e:dd:dd:7435
552c19:dd:c25:c25f:dd4e:dd:dd:7436/1282c19:dd:c25:c25f:dd4e:dd:dd:7436
562c19:dd:c25:c25f:dd4e:dd:dd:7437/1282c19:dd:c25:c25f:dd4e:dd:dd:7437
572c19:dd:c25:c25f:dd4e:dd:dd:7438/1282c19:dd:c25:c25f:dd4e:dd:dd:7438
582c19:dd:c25:c25f:dd4e:dd:dd:7439/1282c19:dd:c25:c25f:dd4e:dd:dd:7439
592c19:dd:c25:c25f:dd4e:dd:dd:743a/1282c19:dd:c25:c25f:dd4e:dd:dd:743a
602c19:dd:c25:c25f:dd4e:dd:dd:743b/1282c19:dd:c25:c25f:dd4e:dd:dd:743b
612c19:dd:c25:c25f:dd4e:dd:dd:743c/1282c19:dd:c25:c25f:dd4e:dd:dd:743c
622c19:dd:c25:c25f:dd4e:dd:dd:743d/1282c19:dd:c25:c25f:dd4e:dd:dd:743d
632c19:dd:c25:c25f:dd4e:dd:dd:743e/1282c19:dd:c25:c25f:dd4e:dd:dd:743e
642c19:dd:c25:c25f:dd4e:dd:dd:743f/1282c19:dd:c25:c25f:dd4e:dd:dd:743f
652c19:dd:c25:c25f:dd4e:dd:dd:7440/1282c19:dd:c25:c25f:dd4e:dd:dd:7440
662c19:dd:c25:c25f:dd4e:dd:dd:7441/1282c19:dd:c25:c25f:dd4e:dd:dd:7441
672c19:dd:c25:c25f:dd4e:dd:dd:7442/1282c19:dd:c25:c25f:dd4e:dd:dd:7442
682c19:dd:c25:c25f:dd4e:dd:dd:7443/1282c19:dd:c25:c25f:dd4e:dd:dd:7443
692c19:dd:c25:c25f:dd4e:dd:dd:7444/1282c19:dd:c25:c25f:dd4e:dd:dd:7444
702c19:dd:c25:c25f:dd4e:dd:dd:7445/1282c19:dd:c25:c25f:dd4e:dd:dd:7445
712c19:dd:c25:c25f:dd4e:dd:dd:7446/1282c19:dd:c25:c25f:dd4e:dd:dd:7446
722c19:dd:c25:c25f:dd4e:dd:dd:7447/1282c19:dd:c25:c25f:dd4e:dd:dd:7447
732c19:dd:c25:c25f:dd4e:dd:dd:7448/1282c19:dd:c25:c25f:dd4e:dd:dd:7448
742c19:dd:c25:c25f:dd4e:dd:dd:7449/1282c19:dd:c25:c25f:dd4e:dd:dd:7449
752c19:dd:c25:c25f:dd4e:dd:dd:744a/1282c19:dd:c25:c25f:dd4e:dd:dd:744a
762c19:dd:c25:c25f:dd4e:dd:dd:744b/1282c19:dd:c25:c25f:dd4e:dd:dd:744b
772c19:dd:c25:c25f:dd4e:dd:dd:744c/1282c19:dd:c25:c25f:dd4e:dd:dd:744c
782c19:dd:c25:c25f:dd4e:dd:dd:744d/1282c19:dd:c25:c25f:dd4e:dd:dd:744d
792c19:dd:c25:c25f:dd4e:dd:dd:744e/1282c19:dd:c25:c25f:dd4e:dd:dd:744e
802c19:dd:c25:c25f:dd4e:dd:dd:744f/1282c19:dd:c25:c25f:dd4e:dd:dd:744f
812c19:dd:c25:c25f:dd4e:dd:dd:7450/1282c19:dd:c25:c25f:dd4e:dd:dd:7450
822c19:dd:c25:c25f:dd4e:dd:dd:7451/1282c19:dd:c25:c25f:dd4e:dd:dd:7451
832c19:dd:c25:c25f:dd4e:dd:dd:7452/1282c19:dd:c25:c25f:dd4e:dd:dd:7452
842c19:dd:c25:c25f:dd4e:dd:dd:7453/1282c19:dd:c25:c25f:dd4e:dd:dd:7453
852c19:dd:c25:c25f:dd4e:dd:dd:7454/1282c19:dd:c25:c25f:dd4e:dd:dd:7454
862c19:dd:c25:c25f:dd4e:dd:dd:7455/1282c19:dd:c25:c25f:dd4e:dd:dd:7455
872c19:dd:c25:c25f:dd4e:dd:dd:7456/1282c19:dd:c25:c25f:dd4e:dd:dd:7456
882c19:dd:c25:c25f:dd4e:dd:dd:7457/1282c19:dd:c25:c25f:dd4e:dd:dd:7457
892c19:dd:c25:c25f:dd4e:dd:dd:7458/1282c19:dd:c25:c25f:dd4e:dd:dd:7458
902c19:dd:c25:c25f:dd4e:dd:dd:7459/1282c19:dd:c25:c25f:dd4e:dd:dd:7459
912c19:dd:c25:c25f:dd4e:dd:dd:745a/1282c19:dd:c25:c25f:dd4e:dd:dd:745a
922c19:dd:c25:c25f:dd4e:dd:dd:745b/1282c19:dd:c25:c25f:dd4e:dd:dd:745b
932c19:dd:c25:c25f:dd4e:dd:dd:745c/1282c19:dd:c25:c25f:dd4e:dd:dd:745c
942c19:dd:c25:c25f:dd4e:dd:dd:745d/1282c19:dd:c25:c25f:dd4e:dd:dd:745d
952c19:dd:c25:c25f:dd4e:dd:dd:745e/1282c19:dd:c25:c25f:dd4e:dd:dd:745e
962c19:dd:c25:c25f:dd4e:dd:dd:745f/1282c19:dd:c25:c25f:dd4e:dd:dd:745f
972c19:dd:c25:c25f:dd4e:dd:dd:7460/1282c19:dd:c25:c25f:dd4e:dd:dd:7460
982c19:dd:c25:c25f:dd4e:dd:dd:7461/1282c19:dd:c25:c25f:dd4e:dd:dd:7461
992c19:dd:c25:c25f:dd4e:dd:dd:7462/1282c19:dd:c25:c25f:dd4e:dd:dd:7462
1002c19:dd:c25:c25f:dd4e:dd:dd:7463/1282c19:dd:c25:c25f:dd4e:dd:dd:7463
1012c19:dd:c25:c25f:dd4e:dd:dd:7464/1282c19:dd:c25:c25f:dd4e:dd:dd:7464
1022c19:dd:c25:c25f:dd4e:dd:dd:7465/1282c19:dd:c25:c25f:dd4e:dd:dd:7465
1032c19:dd:c25:c25f:dd4e:dd:dd:7466/1282c19:dd:c25:c25f:dd4e:dd:dd:7466
1042c19:dd:c25:c25f:dd4e:dd:dd:7467/1282c19:dd:c25:c25f:dd4e:dd:dd:7467
1052c19:dd:c25:c25f:dd4e:dd:dd:7468/1282c19:dd:c25:c25f:dd4e:dd:dd:7468
1062c19:dd:c25:c25f:dd4e:dd:dd:7469/1282c19:dd:c25:c25f:dd4e:dd:dd:7469
1072c19:dd:c25:c25f:dd4e:dd:dd:746a/1282c19:dd:c25:c25f:dd4e:dd:dd:746a
1082c19:dd:c25:c25f:dd4e:dd:dd:746b/1282c19:dd:c25:c25f:dd4e:dd:dd:746b
1092c19:dd:c25:c25f:dd4e:dd:dd:746c/1282c19:dd:c25:c25f:dd4e:dd:dd:746c
1102c19:dd:c25:c25f:dd4e:dd:dd:746d/1282c19:dd:c25:c25f:dd4e:dd:dd:746d
1112c19:dd:c25:c25f:dd4e:dd:dd:746e/1282c19:dd:c25:c25f:dd4e:dd:dd:746e
1122c19:dd:c25:c25f:dd4e:dd:dd:746f/1282c19:dd:c25:c25f:dd4e:dd:dd:746f
1132c19:dd:c25:c25f:dd4e:dd:dd:7470/1282c19:dd:c25:c25f:dd4e:dd:dd:7470
1142c19:dd:c25:c25f:dd4e:dd:dd:7471/1282c19:dd:c25:c25f:dd4e:dd:dd:7471
1152c19:dd:c25:c25f:dd4e:dd:dd:7472/1282c19:dd:c25:c25f:dd4e:dd:dd:7472
1162c19:dd:c25:c25f:dd4e:dd:dd:7473/1282c19:dd:c25:c25f:dd4e:dd:dd:7473
1172c19:dd:c25:c25f:dd4e:dd:dd:7474/1282c19:dd:c25:c25f:dd4e:dd:dd:7474
1182c19:dd:c25:c25f:dd4e:dd:dd:7475/1282c19:dd:c25:c25f:dd4e:dd:dd:7475
1192c19:dd:c25:c25f:dd4e:dd:dd:7476/1282c19:dd:c25:c25f:dd4e:dd:dd:7476
1202c19:dd:c25:c25f:dd4e:dd:dd:7477/1282c19:dd:c25:c25f:dd4e:dd:dd:7477
1212c19:dd:c25:c25f:dd4e:dd:dd:7478/1282c19:dd:c25:c25f:dd4e:dd:dd:7478
1222c19:dd:c25:c25f:dd4e:dd:dd:7479/1282c19:dd:c25:c25f:dd4e:dd:dd:7479
1232c19:dd:c25:c25f:dd4e:dd:dd:747a/1282c19:dd:c25:c25f:dd4e:dd:dd:747a
1242c19:dd:c25:c25f:dd4e:dd:dd:747b/1282c19:dd:c25:c25f:dd4e:dd:dd:747b
1252c19:dd:c25:c25f:dd4e:dd:dd:747c/1282c19:dd:c25:c25f:dd4e:dd:dd:747c
1262c19:dd:c25:c25f:dd4e:dd:dd:747d/1282c19:dd:c25:c25f:dd4e:dd:dd:747d
1272c19:dd:c25:c25f:dd4e:dd:dd:747e/1282c19:dd:c25:c25f:dd4e:dd:dd:747e
1282c19:dd:c25:c25f:dd4e:dd:dd:747f/1282c19:dd:c25:c25f:dd4e:dd:dd:747f
1292c19:dd:c25:c25f:dd4e:dd:dd:7480/1282c19:dd:c25:c25f:dd4e:dd:dd:7480
1302c19:dd:c25:c25f:dd4e:dd:dd:7481/1282c19:dd:c25:c25f:dd4e:dd:dd:7481
1312c19:dd:c25:c25f:dd4e:dd:dd:7482/1282c19:dd:c25:c25f:dd4e:dd:dd:7482
1322c19:dd:c25:c25f:dd4e:dd:dd:7483/1282c19:dd:c25:c25f:dd4e:dd:dd:7483
1332c19:dd:c25:c25f:dd4e:dd:dd:7484/1282c19:dd:c25:c25f:dd4e:dd:dd:7484
1342c19:dd:c25:c25f:dd4e:dd:dd:7485/1282c19:dd:c25:c25f:dd4e:dd:dd:7485
1352c19:dd:c25:c25f:dd4e:dd:dd:7486/1282c19:dd:c25:c25f:dd4e:dd:dd:7486
1362c19:dd:c25:c25f:dd4e:dd:dd:7487/1282c19:dd:c25:c25f:dd4e:dd:dd:7487
1372c19:dd:c25:c25f:dd4e:dd:dd:7488/1282c19:dd:c25:c25f:dd4e:dd:dd:7488
1382c19:dd:c25:c25f:dd4e:dd:dd:7489/1282c19:dd:c25:c25f:dd4e:dd:dd:7489
1392c19:dd:c25:c25f:dd4e:dd:dd:748a/1282c19:dd:c25:c25f:dd4e:dd:dd:748a
1402c19:dd:c25:c25f:dd4e:dd:dd:748b/1282c19:dd:c25:c25f:dd4e:dd:dd:748b
1412c19:dd:c25:c25f:dd4e:dd:dd:748c/1282c19:dd:c25:c25f:dd4e:dd:dd:748c
1422c19:dd:c25:c25f:dd4e:dd:dd:748d/1282c19:dd:c25:c25f:dd4e:dd:dd:748d
1432c19:dd:c25:c25f:dd4e:dd:dd:748e/1282c19:dd:c25:c25f:dd4e:dd:dd:748e
1442c19:dd:c25:c25f:dd4e:dd:dd:748f/1282c19:dd:c25:c25f:dd4e:dd:dd:748f
1452c19:dd:c25:c25f:dd4e:dd:dd:7490/1282c19:dd:c25:c25f:dd4e:dd:dd:7490
1462c19:dd:c25:c25f:dd4e:dd:dd:7491/1282c19:dd:c25:c25f:dd4e:dd:dd:7491
1472c19:dd:c25:c25f:dd4e:dd:dd:7492/1282c19:dd:c25:c25f:dd4e:dd:dd:7492
1482c19:dd:c25:c25f:dd4e:dd:dd:7493/1282c19:dd:c25:c25f:dd4e:dd:dd:7493
1492c19:dd:c25:c25f:dd4e:dd:dd:7494/1282c19:dd:c25:c25f:dd4e:dd:dd:7494
1502c19:dd:c25:c25f:dd4e:dd:dd:7495/1282c19:dd:c25:c25f:dd4e:dd:dd:7495
1512c19:dd:c25:c25f:dd4e:dd:dd:7496/1282c19:dd:c25:c25f:dd4e:dd:dd:7496
1522c19:dd:c25:c25f:dd4e:dd:dd:7497/1282c19:dd:c25:c25f:dd4e:dd:dd:7497
1532c19:dd:c25:c25f:dd4e:dd:dd:7498/1282c19:dd:c25:c25f:dd4e:dd:dd:7498
1542c19:dd:c25:c25f:dd4e:dd:dd:7499/1282c19:dd:c25:c25f:dd4e:dd:dd:7499
1552c19:dd:c25:c25f:dd4e:dd:dd:749a/1282c19:dd:c25:c25f:dd4e:dd:dd:749a
1562c19:dd:c25:c25f:dd4e:dd:dd:749b/1282c19:dd:c25:c25f:dd4e:dd:dd:749b
1572c19:dd:c25:c25f:dd4e:dd:dd:749c/1282c19:dd:c25:c25f:dd4e:dd:dd:749c
1582c19:dd:c25:c25f:dd4e:dd:dd:749d/1282c19:dd:c25:c25f:dd4e:dd:dd:749d
1592c19:dd:c25:c25f:dd4e:dd:dd:749e/1282c19:dd:c25:c25f:dd4e:dd:dd:749e
1602c19:dd:c25:c25f:dd4e:dd:dd:749f/1282c19:dd:c25:c25f:dd4e:dd:dd:749f
1612c19:dd:c25:c25f:dd4e:dd:dd:74a0/1282c19:dd:c25:c25f:dd4e:dd:dd:74a0
1622c19:dd:c25:c25f:dd4e:dd:dd:74a1/1282c19:dd:c25:c25f:dd4e:dd:dd:74a1
1632c19:dd:c25:c25f:dd4e:dd:dd:74a2/1282c19:dd:c25:c25f:dd4e:dd:dd:74a2
1642c19:dd:c25:c25f:dd4e:dd:dd:74a3/1282c19:dd:c25:c25f:dd4e:dd:dd:74a3
1652c19:dd:c25:c25f:dd4e:dd:dd:74a4/1282c19:dd:c25:c25f:dd4e:dd:dd:74a4
1662c19:dd:c25:c25f:dd4e:dd:dd:74a5/1282c19:dd:c25:c25f:dd4e:dd:dd:74a5
1672c19:dd:c25:c25f:dd4e:dd:dd:74a6/1282c19:dd:c25:c25f:dd4e:dd:dd:74a6
1682c19:dd:c25:c25f:dd4e:dd:dd:74a7/1282c19:dd:c25:c25f:dd4e:dd:dd:74a7
1692c19:dd:c25:c25f:dd4e:dd:dd:74a8/1282c19:dd:c25:c25f:dd4e:dd:dd:74a8
1702c19:dd:c25:c25f:dd4e:dd:dd:74a9/1282c19:dd:c25:c25f:dd4e:dd:dd:74a9
1712c19:dd:c25:c25f:dd4e:dd:dd:74aa/1282c19:dd:c25:c25f:dd4e:dd:dd:74aa
1722c19:dd:c25:c25f:dd4e:dd:dd:74ab/1282c19:dd:c25:c25f:dd4e:dd:dd:74ab
1732c19:dd:c25:c25f:dd4e:dd:dd:74ac/1282c19:dd:c25:c25f:dd4e:dd:dd:74ac
1742c19:dd:c25:c25f:dd4e:dd:dd:74ad/1282c19:dd:c25:c25f:dd4e:dd:dd:74ad
1752c19:dd:c25:c25f:dd4e:dd:dd:74ae/1282c19:dd:c25:c25f:dd4e:dd:dd:74ae
1762c19:dd:c25:c25f:dd4e:dd:dd:74af/1282c19:dd:c25:c25f:dd4e:dd:dd:74af
1772c19:dd:c25:c25f:dd4e:dd:dd:74b0/1282c19:dd:c25:c25f:dd4e:dd:dd:74b0
1782c19:dd:c25:c25f:dd4e:dd:dd:74b1/1282c19:dd:c25:c25f:dd4e:dd:dd:74b1
1792c19:dd:c25:c25f:dd4e:dd:dd:74b2/1282c19:dd:c25:c25f:dd4e:dd:dd:74b2
1802c19:dd:c25:c25f:dd4e:dd:dd:74b3/1282c19:dd:c25:c25f:dd4e:dd:dd:74b3
1812c19:dd:c25:c25f:dd4e:dd:dd:74b4/1282c19:dd:c25:c25f:dd4e:dd:dd:74b4
1822c19:dd:c25:c25f:dd4e:dd:dd:74b5/1282c19:dd:c25:c25f:dd4e:dd:dd:74b5
1832c19:dd:c25:c25f:dd4e:dd:dd:74b6/1282c19:dd:c25:c25f:dd4e:dd:dd:74b6
1842c19:dd:c25:c25f:dd4e:dd:dd:74b7/1282c19:dd:c25:c25f:dd4e:dd:dd:74b7
1852c19:dd:c25:c25f:dd4e:dd:dd:74b8/1282c19:dd:c25:c25f:dd4e:dd:dd:74b8
1862c19:dd:c25:c25f:dd4e:dd:dd:74b9/1282c19:dd:c25:c25f:dd4e:dd:dd:74b9
1872c19:dd:c25:c25f:dd4e:dd:dd:74ba/1282c19:dd:c25:c25f:dd4e:dd:dd:74ba
1882c19:dd:c25:c25f:dd4e:dd:dd:74bb/1282c19:dd:c25:c25f:dd4e:dd:dd:74bb
1892c19:dd:c25:c25f:dd4e:dd:dd:74bc/1282c19:dd:c25:c25f:dd4e:dd:dd:74bc
1902c19:dd:c25:c25f:dd4e:dd:dd:74bd/1282c19:dd:c25:c25f:dd4e:dd:dd:74bd
1912c19:dd:c25:c25f:dd4e:dd:dd:74be/1282c19:dd:c25:c25f:dd4e:dd:dd:74be
1922c19:dd:c25:c25f:dd4e:dd:dd:74bf/1282c19:dd:c25:c25f:dd4e:dd:dd:74bf
1932c19:dd:c25:c25f:dd4e:dd:dd:74c0/1282c19:dd:c25:c25f:dd4e:dd:dd:74c0
1942c19:dd:c25:c25f:dd4e:dd:dd:74c1/1282c19:dd:c25:c25f:dd4e:dd:dd:74c1
1952c19:dd:c25:c25f:dd4e:dd:dd:74c2/1282c19:dd:c25:c25f:dd4e:dd:dd:74c2
1962c19:dd:c25:c25f:dd4e:dd:dd:74c3/1282c19:dd:c25:c25f:dd4e:dd:dd:74c3
1972c19:dd:c25:c25f:dd4e:dd:dd:74c4/1282c19:dd:c25:c25f:dd4e:dd:dd:74c4
1982c19:dd:c25:c25f:dd4e:dd:dd:74c5/1282c19:dd:c25:c25f:dd4e:dd:dd:74c5
1992c19:dd:c25:c25f:dd4e:dd:dd:74c6/1282c19:dd:c25:c25f:dd4e:dd:dd:74c6
2002c19:dd:c25:c25f:dd4e:dd:dd:74c7/1282c19:dd:c25:c25f:dd4e:dd:dd:74c7
2012c19:dd:c25:c25f:dd4e:dd:dd:74c8/1282c19:dd:c25:c25f:dd4e:dd:dd:74c8
2022c19:dd:c25:c25f:dd4e:dd:dd:74c9/1282c19:dd:c25:c25f:dd4e:dd:dd:74c9
2032c19:dd:c25:c25f:dd4e:dd:dd:74ca/1282c19:dd:c25:c25f:dd4e:dd:dd:74ca
2042c19:dd:c25:c25f:dd4e:dd:dd:74cb/1282c19:dd:c25:c25f:dd4e:dd:dd:74cb
2052c19:dd:c25:c25f:dd4e:dd:dd:74cc/1282c19:dd:c25:c25f:dd4e:dd:dd:74cc
2062c19:dd:c25:c25f:dd4e:dd:dd:74cd/1282c19:dd:c25:c25f:dd4e:dd:dd:74cd
2072c19:dd:c25:c25f:dd4e:dd:dd:74ce/1282c19:dd:c25:c25f:dd4e:dd:dd:74ce
2082c19:dd:c25:c25f:dd4e:dd:dd:74cf/1282c19:dd:c25:c25f:dd4e:dd:dd:74cf
2092c19:dd:c25:c25f:dd4e:dd:dd:74d0/1282c19:dd:c25:c25f:dd4e:dd:dd:74d0
2102c19:dd:c25:c25f:dd4e:dd:dd:74d1/1282c19:dd:c25:c25f:dd4e:dd:dd:74d1
2112c19:dd:c25:c25f:dd4e:dd:dd:74d2/1282c19:dd:c25:c25f:dd4e:dd:dd:74d2
2122c19:dd:c25:c25f:dd4e:dd:dd:74d3/1282c19:dd:c25:c25f:dd4e:dd:dd:74d3
2132c19:dd:c25:c25f:dd4e:dd:dd:74d4/1282c19:dd:c25:c25f:dd4e:dd:dd:74d4
2142c19:dd:c25:c25f:dd4e:dd:dd:74d5/1282c19:dd:c25:c25f:dd4e:dd:dd:74d5
2152c19:dd:c25:c25f:dd4e:dd:dd:74d6/1282c19:dd:c25:c25f:dd4e:dd:dd:74d6
2162c19:dd:c25:c25f:dd4e:dd:dd:74d7/1282c19:dd:c25:c25f:dd4e:dd:dd:74d7
2172c19:dd:c25:c25f:dd4e:dd:dd:74d8/1282c19:dd:c25:c25f:dd4e:dd:dd:74d8
2182c19:dd:c25:c25f:dd4e:dd:dd:74d9/1282c19:dd:c25:c25f:dd4e:dd:dd:74d9
2192c19:dd:c25:c25f:dd4e:dd:dd:74da/1282c19:dd:c25:c25f:dd4e:dd:dd:74da
2202c19:dd:c25:c25f:dd4e:dd:dd:74db/1282c19:dd:c25:c25f:dd4e:dd:dd:74db
2212c19:dd:c25:c25f:dd4e:dd:dd:74dc/1282c19:dd:c25:c25f:dd4e:dd:dd:74dc
2222c19:dd:c25:c25f:dd4e:dd:dd:74dd/1282c19:dd:c25:c25f:dd4e:dd:dd:74dd
2232c19:dd:c25:c25f:dd4e:dd:dd:74de/1282c19:dd:c25:c25f:dd4e:dd:dd:74de
2242c19:dd:c25:c25f:dd4e:dd:dd:74df/1282c19:dd:c25:c25f:dd4e:dd:dd:74df
2252c19:dd:c25:c25f:dd4e:dd:dd:74e0/1282c19:dd:c25:c25f:dd4e:dd:dd:74e0
2262c19:dd:c25:c25f:dd4e:dd:dd:74e1/1282c19:dd:c25:c25f:dd4e:dd:dd:74e1
2272c19:dd:c25:c25f:dd4e:dd:dd:74e2/1282c19:dd:c25:c25f:dd4e:dd:dd:74e2
2282c19:dd:c25:c25f:dd4e:dd:dd:74e3/1282c19:dd:c25:c25f:dd4e:dd:dd:74e3
2292c19:dd:c25:c25f:dd4e:dd:dd:74e4/1282c19:dd:c25:c25f:dd4e:dd:dd:74e4
2302c19:dd:c25:c25f:dd4e:dd:dd:74e5/1282c19:dd:c25:c25f:dd4e:dd:dd:74e5
2312c19:dd:c25:c25f:dd4e:dd:dd:74e6/1282c19:dd:c25:c25f:dd4e:dd:dd:74e6
2322c19:dd:c25:c25f:dd4e:dd:dd:74e7/1282c19:dd:c25:c25f:dd4e:dd:dd:74e7
2332c19:dd:c25:c25f:dd4e:dd:dd:74e8/1282c19:dd:c25:c25f:dd4e:dd:dd:74e8
2342c19:dd:c25:c25f:dd4e:dd:dd:74e9/1282c19:dd:c25:c25f:dd4e:dd:dd:74e9
2352c19:dd:c25:c25f:dd4e:dd:dd:74ea/1282c19:dd:c25:c25f:dd4e:dd:dd:74ea
2362c19:dd:c25:c25f:dd4e:dd:dd:74eb/1282c19:dd:c25:c25f:dd4e:dd:dd:74eb
2372c19:dd:c25:c25f:dd4e:dd:dd:74ec/1282c19:dd:c25:c25f:dd4e:dd:dd:74ec
2382c19:dd:c25:c25f:dd4e:dd:dd:74ed/1282c19:dd:c25:c25f:dd4e:dd:dd:74ed
2392c19:dd:c25:c25f:dd4e:dd:dd:74ee/1282c19:dd:c25:c25f:dd4e:dd:dd:74ee
2402c19:dd:c25:c25f:dd4e:dd:dd:74ef/1282c19:dd:c25:c25f:dd4e:dd:dd:74ef
2412c19:dd:c25:c25f:dd4e:dd:dd:74f0/1282c19:dd:c25:c25f:dd4e:dd:dd:74f0
2422c19:dd:c25:c25f:dd4e:dd:dd:74f1/1282c19:dd:c25:c25f:dd4e:dd:dd:74f1
2432c19:dd:c25:c25f:dd4e:dd:dd:74f2/1282c19:dd:c25:c25f:dd4e:dd:dd:74f2
2442c19:dd:c25:c25f:dd4e:dd:dd:74f3/1282c19:dd:c25:c25f:dd4e:dd:dd:74f3
2452c19:dd:c25:c25f:dd4e:dd:dd:74f4/1282c19:dd:c25:c25f:dd4e:dd:dd:74f4
2462c19:dd:c25:c25f:dd4e:dd:dd:74f5/1282c19:dd:c25:c25f:dd4e:dd:dd:74f5
2472c19:dd:c25:c25f:dd4e:dd:dd:74f6/1282c19:dd:c25:c25f:dd4e:dd:dd:74f6
2482c19:dd:c25:c25f:dd4e:dd:dd:74f7/1282c19:dd:c25:c25f:dd4e:dd:dd:74f7
2492c19:dd:c25:c25f:dd4e:dd:dd:74f8/1282c19:dd:c25:c25f:dd4e:dd:dd:74f8
2502c19:dd:c25:c25f:dd4e:dd:dd:74f9/1282c19:dd:c25:c25f:dd4e:dd:dd:74f9
2512c19:dd:c25:c25f:dd4e:dd:dd:74fa/1282c19:dd:c25:c25f:dd4e:dd:dd:74fa
2522c19:dd:c25:c25f:dd4e:dd:dd:74fb/1282c19:dd:c25:c25f:dd4e:dd:dd:74fb
2532c19:dd:c25:c25f:dd4e:dd:dd:74fc/1282c19:dd:c25:c25f:dd4e:dd:dd:74fc
2542c19:dd:c25:c25f:dd4e:dd:dd:74fd/1282c19:dd:c25:c25f:dd4e:dd:dd:74fd
2552c19:dd:c25:c25f:dd4e:dd:dd:74fe/1282c19:dd:c25:c25f:dd4e:dd:dd:74fe
2562c19:dd:c25:c25f:dd4e:dd:dd:74ff/1282c19:dd:c25:c25f:dd4e:dd:dd:74ff

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.