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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:3400/120
First address
2c19:dd:d9:dd:c25:c25:94de:3400
Last address
2c19:dd:d9:dd:c25:c25:94de:34ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:3400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.3.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:3400/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:3400/1282c19:dd:d9:dd:c25:c25:94de:3400
22c19:dd:d9:dd:c25:c25:94de:3401/1282c19:dd:d9:dd:c25:c25:94de:3401
32c19:dd:d9:dd:c25:c25:94de:3402/1282c19:dd:d9:dd:c25:c25:94de:3402
42c19:dd:d9:dd:c25:c25:94de:3403/1282c19:dd:d9:dd:c25:c25:94de:3403
52c19:dd:d9:dd:c25:c25:94de:3404/1282c19:dd:d9:dd:c25:c25:94de:3404
62c19:dd:d9:dd:c25:c25:94de:3405/1282c19:dd:d9:dd:c25:c25:94de:3405
72c19:dd:d9:dd:c25:c25:94de:3406/1282c19:dd:d9:dd:c25:c25:94de:3406
82c19:dd:d9:dd:c25:c25:94de:3407/1282c19:dd:d9:dd:c25:c25:94de:3407
92c19:dd:d9:dd:c25:c25:94de:3408/1282c19:dd:d9:dd:c25:c25:94de:3408
102c19:dd:d9:dd:c25:c25:94de:3409/1282c19:dd:d9:dd:c25:c25:94de:3409
112c19:dd:d9:dd:c25:c25:94de:340a/1282c19:dd:d9:dd:c25:c25:94de:340a
122c19:dd:d9:dd:c25:c25:94de:340b/1282c19:dd:d9:dd:c25:c25:94de:340b
132c19:dd:d9:dd:c25:c25:94de:340c/1282c19:dd:d9:dd:c25:c25:94de:340c
142c19:dd:d9:dd:c25:c25:94de:340d/1282c19:dd:d9:dd:c25:c25:94de:340d
152c19:dd:d9:dd:c25:c25:94de:340e/1282c19:dd:d9:dd:c25:c25:94de:340e
162c19:dd:d9:dd:c25:c25:94de:340f/1282c19:dd:d9:dd:c25:c25:94de:340f
172c19:dd:d9:dd:c25:c25:94de:3410/1282c19:dd:d9:dd:c25:c25:94de:3410
182c19:dd:d9:dd:c25:c25:94de:3411/1282c19:dd:d9:dd:c25:c25:94de:3411
192c19:dd:d9:dd:c25:c25:94de:3412/1282c19:dd:d9:dd:c25:c25:94de:3412
202c19:dd:d9:dd:c25:c25:94de:3413/1282c19:dd:d9:dd:c25:c25:94de:3413
212c19:dd:d9:dd:c25:c25:94de:3414/1282c19:dd:d9:dd:c25:c25:94de:3414
222c19:dd:d9:dd:c25:c25:94de:3415/1282c19:dd:d9:dd:c25:c25:94de:3415
232c19:dd:d9:dd:c25:c25:94de:3416/1282c19:dd:d9:dd:c25:c25:94de:3416
242c19:dd:d9:dd:c25:c25:94de:3417/1282c19:dd:d9:dd:c25:c25:94de:3417
252c19:dd:d9:dd:c25:c25:94de:3418/1282c19:dd:d9:dd:c25:c25:94de:3418
262c19:dd:d9:dd:c25:c25:94de:3419/1282c19:dd:d9:dd:c25:c25:94de:3419
272c19:dd:d9:dd:c25:c25:94de:341a/1282c19:dd:d9:dd:c25:c25:94de:341a
282c19:dd:d9:dd:c25:c25:94de:341b/1282c19:dd:d9:dd:c25:c25:94de:341b
292c19:dd:d9:dd:c25:c25:94de:341c/1282c19:dd:d9:dd:c25:c25:94de:341c
302c19:dd:d9:dd:c25:c25:94de:341d/1282c19:dd:d9:dd:c25:c25:94de:341d
312c19:dd:d9:dd:c25:c25:94de:341e/1282c19:dd:d9:dd:c25:c25:94de:341e
322c19:dd:d9:dd:c25:c25:94de:341f/1282c19:dd:d9:dd:c25:c25:94de:341f
332c19:dd:d9:dd:c25:c25:94de:3420/1282c19:dd:d9:dd:c25:c25:94de:3420
342c19:dd:d9:dd:c25:c25:94de:3421/1282c19:dd:d9:dd:c25:c25:94de:3421
352c19:dd:d9:dd:c25:c25:94de:3422/1282c19:dd:d9:dd:c25:c25:94de:3422
362c19:dd:d9:dd:c25:c25:94de:3423/1282c19:dd:d9:dd:c25:c25:94de:3423
372c19:dd:d9:dd:c25:c25:94de:3424/1282c19:dd:d9:dd:c25:c25:94de:3424
382c19:dd:d9:dd:c25:c25:94de:3425/1282c19:dd:d9:dd:c25:c25:94de:3425
392c19:dd:d9:dd:c25:c25:94de:3426/1282c19:dd:d9:dd:c25:c25:94de:3426
402c19:dd:d9:dd:c25:c25:94de:3427/1282c19:dd:d9:dd:c25:c25:94de:3427
412c19:dd:d9:dd:c25:c25:94de:3428/1282c19:dd:d9:dd:c25:c25:94de:3428
422c19:dd:d9:dd:c25:c25:94de:3429/1282c19:dd:d9:dd:c25:c25:94de:3429
432c19:dd:d9:dd:c25:c25:94de:342a/1282c19:dd:d9:dd:c25:c25:94de:342a
442c19:dd:d9:dd:c25:c25:94de:342b/1282c19:dd:d9:dd:c25:c25:94de:342b
452c19:dd:d9:dd:c25:c25:94de:342c/1282c19:dd:d9:dd:c25:c25:94de:342c
462c19:dd:d9:dd:c25:c25:94de:342d/1282c19:dd:d9:dd:c25:c25:94de:342d
472c19:dd:d9:dd:c25:c25:94de:342e/1282c19:dd:d9:dd:c25:c25:94de:342e
482c19:dd:d9:dd:c25:c25:94de:342f/1282c19:dd:d9:dd:c25:c25:94de:342f
492c19:dd:d9:dd:c25:c25:94de:3430/1282c19:dd:d9:dd:c25:c25:94de:3430
502c19:dd:d9:dd:c25:c25:94de:3431/1282c19:dd:d9:dd:c25:c25:94de:3431
512c19:dd:d9:dd:c25:c25:94de:3432/1282c19:dd:d9:dd:c25:c25:94de:3432
522c19:dd:d9:dd:c25:c25:94de:3433/1282c19:dd:d9:dd:c25:c25:94de:3433
532c19:dd:d9:dd:c25:c25:94de:3434/1282c19:dd:d9:dd:c25:c25:94de:3434
542c19:dd:d9:dd:c25:c25:94de:3435/1282c19:dd:d9:dd:c25:c25:94de:3435
552c19:dd:d9:dd:c25:c25:94de:3436/1282c19:dd:d9:dd:c25:c25:94de:3436
562c19:dd:d9:dd:c25:c25:94de:3437/1282c19:dd:d9:dd:c25:c25:94de:3437
572c19:dd:d9:dd:c25:c25:94de:3438/1282c19:dd:d9:dd:c25:c25:94de:3438
582c19:dd:d9:dd:c25:c25:94de:3439/1282c19:dd:d9:dd:c25:c25:94de:3439
592c19:dd:d9:dd:c25:c25:94de:343a/1282c19:dd:d9:dd:c25:c25:94de:343a
602c19:dd:d9:dd:c25:c25:94de:343b/1282c19:dd:d9:dd:c25:c25:94de:343b
612c19:dd:d9:dd:c25:c25:94de:343c/1282c19:dd:d9:dd:c25:c25:94de:343c
622c19:dd:d9:dd:c25:c25:94de:343d/1282c19:dd:d9:dd:c25:c25:94de:343d
632c19:dd:d9:dd:c25:c25:94de:343e/1282c19:dd:d9:dd:c25:c25:94de:343e
642c19:dd:d9:dd:c25:c25:94de:343f/1282c19:dd:d9:dd:c25:c25:94de:343f
652c19:dd:d9:dd:c25:c25:94de:3440/1282c19:dd:d9:dd:c25:c25:94de:3440
662c19:dd:d9:dd:c25:c25:94de:3441/1282c19:dd:d9:dd:c25:c25:94de:3441
672c19:dd:d9:dd:c25:c25:94de:3442/1282c19:dd:d9:dd:c25:c25:94de:3442
682c19:dd:d9:dd:c25:c25:94de:3443/1282c19:dd:d9:dd:c25:c25:94de:3443
692c19:dd:d9:dd:c25:c25:94de:3444/1282c19:dd:d9:dd:c25:c25:94de:3444
702c19:dd:d9:dd:c25:c25:94de:3445/1282c19:dd:d9:dd:c25:c25:94de:3445
712c19:dd:d9:dd:c25:c25:94de:3446/1282c19:dd:d9:dd:c25:c25:94de:3446
722c19:dd:d9:dd:c25:c25:94de:3447/1282c19:dd:d9:dd:c25:c25:94de:3447
732c19:dd:d9:dd:c25:c25:94de:3448/1282c19:dd:d9:dd:c25:c25:94de:3448
742c19:dd:d9:dd:c25:c25:94de:3449/1282c19:dd:d9:dd:c25:c25:94de:3449
752c19:dd:d9:dd:c25:c25:94de:344a/1282c19:dd:d9:dd:c25:c25:94de:344a
762c19:dd:d9:dd:c25:c25:94de:344b/1282c19:dd:d9:dd:c25:c25:94de:344b
772c19:dd:d9:dd:c25:c25:94de:344c/1282c19:dd:d9:dd:c25:c25:94de:344c
782c19:dd:d9:dd:c25:c25:94de:344d/1282c19:dd:d9:dd:c25:c25:94de:344d
792c19:dd:d9:dd:c25:c25:94de:344e/1282c19:dd:d9:dd:c25:c25:94de:344e
802c19:dd:d9:dd:c25:c25:94de:344f/1282c19:dd:d9:dd:c25:c25:94de:344f
812c19:dd:d9:dd:c25:c25:94de:3450/1282c19:dd:d9:dd:c25:c25:94de:3450
822c19:dd:d9:dd:c25:c25:94de:3451/1282c19:dd:d9:dd:c25:c25:94de:3451
832c19:dd:d9:dd:c25:c25:94de:3452/1282c19:dd:d9:dd:c25:c25:94de:3452
842c19:dd:d9:dd:c25:c25:94de:3453/1282c19:dd:d9:dd:c25:c25:94de:3453
852c19:dd:d9:dd:c25:c25:94de:3454/1282c19:dd:d9:dd:c25:c25:94de:3454
862c19:dd:d9:dd:c25:c25:94de:3455/1282c19:dd:d9:dd:c25:c25:94de:3455
872c19:dd:d9:dd:c25:c25:94de:3456/1282c19:dd:d9:dd:c25:c25:94de:3456
882c19:dd:d9:dd:c25:c25:94de:3457/1282c19:dd:d9:dd:c25:c25:94de:3457
892c19:dd:d9:dd:c25:c25:94de:3458/1282c19:dd:d9:dd:c25:c25:94de:3458
902c19:dd:d9:dd:c25:c25:94de:3459/1282c19:dd:d9:dd:c25:c25:94de:3459
912c19:dd:d9:dd:c25:c25:94de:345a/1282c19:dd:d9:dd:c25:c25:94de:345a
922c19:dd:d9:dd:c25:c25:94de:345b/1282c19:dd:d9:dd:c25:c25:94de:345b
932c19:dd:d9:dd:c25:c25:94de:345c/1282c19:dd:d9:dd:c25:c25:94de:345c
942c19:dd:d9:dd:c25:c25:94de:345d/1282c19:dd:d9:dd:c25:c25:94de:345d
952c19:dd:d9:dd:c25:c25:94de:345e/1282c19:dd:d9:dd:c25:c25:94de:345e
962c19:dd:d9:dd:c25:c25:94de:345f/1282c19:dd:d9:dd:c25:c25:94de:345f
972c19:dd:d9:dd:c25:c25:94de:3460/1282c19:dd:d9:dd:c25:c25:94de:3460
982c19:dd:d9:dd:c25:c25:94de:3461/1282c19:dd:d9:dd:c25:c25:94de:3461
992c19:dd:d9:dd:c25:c25:94de:3462/1282c19:dd:d9:dd:c25:c25:94de:3462
1002c19:dd:d9:dd:c25:c25:94de:3463/1282c19:dd:d9:dd:c25:c25:94de:3463
1012c19:dd:d9:dd:c25:c25:94de:3464/1282c19:dd:d9:dd:c25:c25:94de:3464
1022c19:dd:d9:dd:c25:c25:94de:3465/1282c19:dd:d9:dd:c25:c25:94de:3465
1032c19:dd:d9:dd:c25:c25:94de:3466/1282c19:dd:d9:dd:c25:c25:94de:3466
1042c19:dd:d9:dd:c25:c25:94de:3467/1282c19:dd:d9:dd:c25:c25:94de:3467
1052c19:dd:d9:dd:c25:c25:94de:3468/1282c19:dd:d9:dd:c25:c25:94de:3468
1062c19:dd:d9:dd:c25:c25:94de:3469/1282c19:dd:d9:dd:c25:c25:94de:3469
1072c19:dd:d9:dd:c25:c25:94de:346a/1282c19:dd:d9:dd:c25:c25:94de:346a
1082c19:dd:d9:dd:c25:c25:94de:346b/1282c19:dd:d9:dd:c25:c25:94de:346b
1092c19:dd:d9:dd:c25:c25:94de:346c/1282c19:dd:d9:dd:c25:c25:94de:346c
1102c19:dd:d9:dd:c25:c25:94de:346d/1282c19:dd:d9:dd:c25:c25:94de:346d
1112c19:dd:d9:dd:c25:c25:94de:346e/1282c19:dd:d9:dd:c25:c25:94de:346e
1122c19:dd:d9:dd:c25:c25:94de:346f/1282c19:dd:d9:dd:c25:c25:94de:346f
1132c19:dd:d9:dd:c25:c25:94de:3470/1282c19:dd:d9:dd:c25:c25:94de:3470
1142c19:dd:d9:dd:c25:c25:94de:3471/1282c19:dd:d9:dd:c25:c25:94de:3471
1152c19:dd:d9:dd:c25:c25:94de:3472/1282c19:dd:d9:dd:c25:c25:94de:3472
1162c19:dd:d9:dd:c25:c25:94de:3473/1282c19:dd:d9:dd:c25:c25:94de:3473
1172c19:dd:d9:dd:c25:c25:94de:3474/1282c19:dd:d9:dd:c25:c25:94de:3474
1182c19:dd:d9:dd:c25:c25:94de:3475/1282c19:dd:d9:dd:c25:c25:94de:3475
1192c19:dd:d9:dd:c25:c25:94de:3476/1282c19:dd:d9:dd:c25:c25:94de:3476
1202c19:dd:d9:dd:c25:c25:94de:3477/1282c19:dd:d9:dd:c25:c25:94de:3477
1212c19:dd:d9:dd:c25:c25:94de:3478/1282c19:dd:d9:dd:c25:c25:94de:3478
1222c19:dd:d9:dd:c25:c25:94de:3479/1282c19:dd:d9:dd:c25:c25:94de:3479
1232c19:dd:d9:dd:c25:c25:94de:347a/1282c19:dd:d9:dd:c25:c25:94de:347a
1242c19:dd:d9:dd:c25:c25:94de:347b/1282c19:dd:d9:dd:c25:c25:94de:347b
1252c19:dd:d9:dd:c25:c25:94de:347c/1282c19:dd:d9:dd:c25:c25:94de:347c
1262c19:dd:d9:dd:c25:c25:94de:347d/1282c19:dd:d9:dd:c25:c25:94de:347d
1272c19:dd:d9:dd:c25:c25:94de:347e/1282c19:dd:d9:dd:c25:c25:94de:347e
1282c19:dd:d9:dd:c25:c25:94de:347f/1282c19:dd:d9:dd:c25:c25:94de:347f
1292c19:dd:d9:dd:c25:c25:94de:3480/1282c19:dd:d9:dd:c25:c25:94de:3480
1302c19:dd:d9:dd:c25:c25:94de:3481/1282c19:dd:d9:dd:c25:c25:94de:3481
1312c19:dd:d9:dd:c25:c25:94de:3482/1282c19:dd:d9:dd:c25:c25:94de:3482
1322c19:dd:d9:dd:c25:c25:94de:3483/1282c19:dd:d9:dd:c25:c25:94de:3483
1332c19:dd:d9:dd:c25:c25:94de:3484/1282c19:dd:d9:dd:c25:c25:94de:3484
1342c19:dd:d9:dd:c25:c25:94de:3485/1282c19:dd:d9:dd:c25:c25:94de:3485
1352c19:dd:d9:dd:c25:c25:94de:3486/1282c19:dd:d9:dd:c25:c25:94de:3486
1362c19:dd:d9:dd:c25:c25:94de:3487/1282c19:dd:d9:dd:c25:c25:94de:3487
1372c19:dd:d9:dd:c25:c25:94de:3488/1282c19:dd:d9:dd:c25:c25:94de:3488
1382c19:dd:d9:dd:c25:c25:94de:3489/1282c19:dd:d9:dd:c25:c25:94de:3489
1392c19:dd:d9:dd:c25:c25:94de:348a/1282c19:dd:d9:dd:c25:c25:94de:348a
1402c19:dd:d9:dd:c25:c25:94de:348b/1282c19:dd:d9:dd:c25:c25:94de:348b
1412c19:dd:d9:dd:c25:c25:94de:348c/1282c19:dd:d9:dd:c25:c25:94de:348c
1422c19:dd:d9:dd:c25:c25:94de:348d/1282c19:dd:d9:dd:c25:c25:94de:348d
1432c19:dd:d9:dd:c25:c25:94de:348e/1282c19:dd:d9:dd:c25:c25:94de:348e
1442c19:dd:d9:dd:c25:c25:94de:348f/1282c19:dd:d9:dd:c25:c25:94de:348f
1452c19:dd:d9:dd:c25:c25:94de:3490/1282c19:dd:d9:dd:c25:c25:94de:3490
1462c19:dd:d9:dd:c25:c25:94de:3491/1282c19:dd:d9:dd:c25:c25:94de:3491
1472c19:dd:d9:dd:c25:c25:94de:3492/1282c19:dd:d9:dd:c25:c25:94de:3492
1482c19:dd:d9:dd:c25:c25:94de:3493/1282c19:dd:d9:dd:c25:c25:94de:3493
1492c19:dd:d9:dd:c25:c25:94de:3494/1282c19:dd:d9:dd:c25:c25:94de:3494
1502c19:dd:d9:dd:c25:c25:94de:3495/1282c19:dd:d9:dd:c25:c25:94de:3495
1512c19:dd:d9:dd:c25:c25:94de:3496/1282c19:dd:d9:dd:c25:c25:94de:3496
1522c19:dd:d9:dd:c25:c25:94de:3497/1282c19:dd:d9:dd:c25:c25:94de:3497
1532c19:dd:d9:dd:c25:c25:94de:3498/1282c19:dd:d9:dd:c25:c25:94de:3498
1542c19:dd:d9:dd:c25:c25:94de:3499/1282c19:dd:d9:dd:c25:c25:94de:3499
1552c19:dd:d9:dd:c25:c25:94de:349a/1282c19:dd:d9:dd:c25:c25:94de:349a
1562c19:dd:d9:dd:c25:c25:94de:349b/1282c19:dd:d9:dd:c25:c25:94de:349b
1572c19:dd:d9:dd:c25:c25:94de:349c/1282c19:dd:d9:dd:c25:c25:94de:349c
1582c19:dd:d9:dd:c25:c25:94de:349d/1282c19:dd:d9:dd:c25:c25:94de:349d
1592c19:dd:d9:dd:c25:c25:94de:349e/1282c19:dd:d9:dd:c25:c25:94de:349e
1602c19:dd:d9:dd:c25:c25:94de:349f/1282c19:dd:d9:dd:c25:c25:94de:349f
1612c19:dd:d9:dd:c25:c25:94de:34a0/1282c19:dd:d9:dd:c25:c25:94de:34a0
1622c19:dd:d9:dd:c25:c25:94de:34a1/1282c19:dd:d9:dd:c25:c25:94de:34a1
1632c19:dd:d9:dd:c25:c25:94de:34a2/1282c19:dd:d9:dd:c25:c25:94de:34a2
1642c19:dd:d9:dd:c25:c25:94de:34a3/1282c19:dd:d9:dd:c25:c25:94de:34a3
1652c19:dd:d9:dd:c25:c25:94de:34a4/1282c19:dd:d9:dd:c25:c25:94de:34a4
1662c19:dd:d9:dd:c25:c25:94de:34a5/1282c19:dd:d9:dd:c25:c25:94de:34a5
1672c19:dd:d9:dd:c25:c25:94de:34a6/1282c19:dd:d9:dd:c25:c25:94de:34a6
1682c19:dd:d9:dd:c25:c25:94de:34a7/1282c19:dd:d9:dd:c25:c25:94de:34a7
1692c19:dd:d9:dd:c25:c25:94de:34a8/1282c19:dd:d9:dd:c25:c25:94de:34a8
1702c19:dd:d9:dd:c25:c25:94de:34a9/1282c19:dd:d9:dd:c25:c25:94de:34a9
1712c19:dd:d9:dd:c25:c25:94de:34aa/1282c19:dd:d9:dd:c25:c25:94de:34aa
1722c19:dd:d9:dd:c25:c25:94de:34ab/1282c19:dd:d9:dd:c25:c25:94de:34ab
1732c19:dd:d9:dd:c25:c25:94de:34ac/1282c19:dd:d9:dd:c25:c25:94de:34ac
1742c19:dd:d9:dd:c25:c25:94de:34ad/1282c19:dd:d9:dd:c25:c25:94de:34ad
1752c19:dd:d9:dd:c25:c25:94de:34ae/1282c19:dd:d9:dd:c25:c25:94de:34ae
1762c19:dd:d9:dd:c25:c25:94de:34af/1282c19:dd:d9:dd:c25:c25:94de:34af
1772c19:dd:d9:dd:c25:c25:94de:34b0/1282c19:dd:d9:dd:c25:c25:94de:34b0
1782c19:dd:d9:dd:c25:c25:94de:34b1/1282c19:dd:d9:dd:c25:c25:94de:34b1
1792c19:dd:d9:dd:c25:c25:94de:34b2/1282c19:dd:d9:dd:c25:c25:94de:34b2
1802c19:dd:d9:dd:c25:c25:94de:34b3/1282c19:dd:d9:dd:c25:c25:94de:34b3
1812c19:dd:d9:dd:c25:c25:94de:34b4/1282c19:dd:d9:dd:c25:c25:94de:34b4
1822c19:dd:d9:dd:c25:c25:94de:34b5/1282c19:dd:d9:dd:c25:c25:94de:34b5
1832c19:dd:d9:dd:c25:c25:94de:34b6/1282c19:dd:d9:dd:c25:c25:94de:34b6
1842c19:dd:d9:dd:c25:c25:94de:34b7/1282c19:dd:d9:dd:c25:c25:94de:34b7
1852c19:dd:d9:dd:c25:c25:94de:34b8/1282c19:dd:d9:dd:c25:c25:94de:34b8
1862c19:dd:d9:dd:c25:c25:94de:34b9/1282c19:dd:d9:dd:c25:c25:94de:34b9
1872c19:dd:d9:dd:c25:c25:94de:34ba/1282c19:dd:d9:dd:c25:c25:94de:34ba
1882c19:dd:d9:dd:c25:c25:94de:34bb/1282c19:dd:d9:dd:c25:c25:94de:34bb
1892c19:dd:d9:dd:c25:c25:94de:34bc/1282c19:dd:d9:dd:c25:c25:94de:34bc
1902c19:dd:d9:dd:c25:c25:94de:34bd/1282c19:dd:d9:dd:c25:c25:94de:34bd
1912c19:dd:d9:dd:c25:c25:94de:34be/1282c19:dd:d9:dd:c25:c25:94de:34be
1922c19:dd:d9:dd:c25:c25:94de:34bf/1282c19:dd:d9:dd:c25:c25:94de:34bf
1932c19:dd:d9:dd:c25:c25:94de:34c0/1282c19:dd:d9:dd:c25:c25:94de:34c0
1942c19:dd:d9:dd:c25:c25:94de:34c1/1282c19:dd:d9:dd:c25:c25:94de:34c1
1952c19:dd:d9:dd:c25:c25:94de:34c2/1282c19:dd:d9:dd:c25:c25:94de:34c2
1962c19:dd:d9:dd:c25:c25:94de:34c3/1282c19:dd:d9:dd:c25:c25:94de:34c3
1972c19:dd:d9:dd:c25:c25:94de:34c4/1282c19:dd:d9:dd:c25:c25:94de:34c4
1982c19:dd:d9:dd:c25:c25:94de:34c5/1282c19:dd:d9:dd:c25:c25:94de:34c5
1992c19:dd:d9:dd:c25:c25:94de:34c6/1282c19:dd:d9:dd:c25:c25:94de:34c6
2002c19:dd:d9:dd:c25:c25:94de:34c7/1282c19:dd:d9:dd:c25:c25:94de:34c7
2012c19:dd:d9:dd:c25:c25:94de:34c8/1282c19:dd:d9:dd:c25:c25:94de:34c8
2022c19:dd:d9:dd:c25:c25:94de:34c9/1282c19:dd:d9:dd:c25:c25:94de:34c9
2032c19:dd:d9:dd:c25:c25:94de:34ca/1282c19:dd:d9:dd:c25:c25:94de:34ca
2042c19:dd:d9:dd:c25:c25:94de:34cb/1282c19:dd:d9:dd:c25:c25:94de:34cb
2052c19:dd:d9:dd:c25:c25:94de:34cc/1282c19:dd:d9:dd:c25:c25:94de:34cc
2062c19:dd:d9:dd:c25:c25:94de:34cd/1282c19:dd:d9:dd:c25:c25:94de:34cd
2072c19:dd:d9:dd:c25:c25:94de:34ce/1282c19:dd:d9:dd:c25:c25:94de:34ce
2082c19:dd:d9:dd:c25:c25:94de:34cf/1282c19:dd:d9:dd:c25:c25:94de:34cf
2092c19:dd:d9:dd:c25:c25:94de:34d0/1282c19:dd:d9:dd:c25:c25:94de:34d0
2102c19:dd:d9:dd:c25:c25:94de:34d1/1282c19:dd:d9:dd:c25:c25:94de:34d1
2112c19:dd:d9:dd:c25:c25:94de:34d2/1282c19:dd:d9:dd:c25:c25:94de:34d2
2122c19:dd:d9:dd:c25:c25:94de:34d3/1282c19:dd:d9:dd:c25:c25:94de:34d3
2132c19:dd:d9:dd:c25:c25:94de:34d4/1282c19:dd:d9:dd:c25:c25:94de:34d4
2142c19:dd:d9:dd:c25:c25:94de:34d5/1282c19:dd:d9:dd:c25:c25:94de:34d5
2152c19:dd:d9:dd:c25:c25:94de:34d6/1282c19:dd:d9:dd:c25:c25:94de:34d6
2162c19:dd:d9:dd:c25:c25:94de:34d7/1282c19:dd:d9:dd:c25:c25:94de:34d7
2172c19:dd:d9:dd:c25:c25:94de:34d8/1282c19:dd:d9:dd:c25:c25:94de:34d8
2182c19:dd:d9:dd:c25:c25:94de:34d9/1282c19:dd:d9:dd:c25:c25:94de:34d9
2192c19:dd:d9:dd:c25:c25:94de:34da/1282c19:dd:d9:dd:c25:c25:94de:34da
2202c19:dd:d9:dd:c25:c25:94de:34db/1282c19:dd:d9:dd:c25:c25:94de:34db
2212c19:dd:d9:dd:c25:c25:94de:34dc/1282c19:dd:d9:dd:c25:c25:94de:34dc
2222c19:dd:d9:dd:c25:c25:94de:34dd/1282c19:dd:d9:dd:c25:c25:94de:34dd
2232c19:dd:d9:dd:c25:c25:94de:34de/1282c19:dd:d9:dd:c25:c25:94de:34de
2242c19:dd:d9:dd:c25:c25:94de:34df/1282c19:dd:d9:dd:c25:c25:94de:34df
2252c19:dd:d9:dd:c25:c25:94de:34e0/1282c19:dd:d9:dd:c25:c25:94de:34e0
2262c19:dd:d9:dd:c25:c25:94de:34e1/1282c19:dd:d9:dd:c25:c25:94de:34e1
2272c19:dd:d9:dd:c25:c25:94de:34e2/1282c19:dd:d9:dd:c25:c25:94de:34e2
2282c19:dd:d9:dd:c25:c25:94de:34e3/1282c19:dd:d9:dd:c25:c25:94de:34e3
2292c19:dd:d9:dd:c25:c25:94de:34e4/1282c19:dd:d9:dd:c25:c25:94de:34e4
2302c19:dd:d9:dd:c25:c25:94de:34e5/1282c19:dd:d9:dd:c25:c25:94de:34e5
2312c19:dd:d9:dd:c25:c25:94de:34e6/1282c19:dd:d9:dd:c25:c25:94de:34e6
2322c19:dd:d9:dd:c25:c25:94de:34e7/1282c19:dd:d9:dd:c25:c25:94de:34e7
2332c19:dd:d9:dd:c25:c25:94de:34e8/1282c19:dd:d9:dd:c25:c25:94de:34e8
2342c19:dd:d9:dd:c25:c25:94de:34e9/1282c19:dd:d9:dd:c25:c25:94de:34e9
2352c19:dd:d9:dd:c25:c25:94de:34ea/1282c19:dd:d9:dd:c25:c25:94de:34ea
2362c19:dd:d9:dd:c25:c25:94de:34eb/1282c19:dd:d9:dd:c25:c25:94de:34eb
2372c19:dd:d9:dd:c25:c25:94de:34ec/1282c19:dd:d9:dd:c25:c25:94de:34ec
2382c19:dd:d9:dd:c25:c25:94de:34ed/1282c19:dd:d9:dd:c25:c25:94de:34ed
2392c19:dd:d9:dd:c25:c25:94de:34ee/1282c19:dd:d9:dd:c25:c25:94de:34ee
2402c19:dd:d9:dd:c25:c25:94de:34ef/1282c19:dd:d9:dd:c25:c25:94de:34ef
2412c19:dd:d9:dd:c25:c25:94de:34f0/1282c19:dd:d9:dd:c25:c25:94de:34f0
2422c19:dd:d9:dd:c25:c25:94de:34f1/1282c19:dd:d9:dd:c25:c25:94de:34f1
2432c19:dd:d9:dd:c25:c25:94de:34f2/1282c19:dd:d9:dd:c25:c25:94de:34f2
2442c19:dd:d9:dd:c25:c25:94de:34f3/1282c19:dd:d9:dd:c25:c25:94de:34f3
2452c19:dd:d9:dd:c25:c25:94de:34f4/1282c19:dd:d9:dd:c25:c25:94de:34f4
2462c19:dd:d9:dd:c25:c25:94de:34f5/1282c19:dd:d9:dd:c25:c25:94de:34f5
2472c19:dd:d9:dd:c25:c25:94de:34f6/1282c19:dd:d9:dd:c25:c25:94de:34f6
2482c19:dd:d9:dd:c25:c25:94de:34f7/1282c19:dd:d9:dd:c25:c25:94de:34f7
2492c19:dd:d9:dd:c25:c25:94de:34f8/1282c19:dd:d9:dd:c25:c25:94de:34f8
2502c19:dd:d9:dd:c25:c25:94de:34f9/1282c19:dd:d9:dd:c25:c25:94de:34f9
2512c19:dd:d9:dd:c25:c25:94de:34fa/1282c19:dd:d9:dd:c25:c25:94de:34fa
2522c19:dd:d9:dd:c25:c25:94de:34fb/1282c19:dd:d9:dd:c25:c25:94de:34fb
2532c19:dd:d9:dd:c25:c25:94de:34fc/1282c19:dd:d9:dd:c25:c25:94de:34fc
2542c19:dd:d9:dd:c25:c25:94de:34fd/1282c19:dd:d9:dd:c25:c25:94de:34fd
2552c19:dd:d9:dd:c25:c25:94de:34fe/1282c19:dd:d9:dd:c25:c25:94de:34fe
2562c19:dd:d9:dd:c25:c25:94de:34ff/1282c19:dd:d9:dd:c25:c25:94de:34ff

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.