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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:3500/120
First address
2c19:dd:d9:dd:c25:c25:94de:3500
Last address
2c19:dd:d9:dd:c25:c25:94de:35ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:3500
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.3.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:3500/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:3500/1282c19:dd:d9:dd:c25:c25:94de:3500
22c19:dd:d9:dd:c25:c25:94de:3501/1282c19:dd:d9:dd:c25:c25:94de:3501
32c19:dd:d9:dd:c25:c25:94de:3502/1282c19:dd:d9:dd:c25:c25:94de:3502
42c19:dd:d9:dd:c25:c25:94de:3503/1282c19:dd:d9:dd:c25:c25:94de:3503
52c19:dd:d9:dd:c25:c25:94de:3504/1282c19:dd:d9:dd:c25:c25:94de:3504
62c19:dd:d9:dd:c25:c25:94de:3505/1282c19:dd:d9:dd:c25:c25:94de:3505
72c19:dd:d9:dd:c25:c25:94de:3506/1282c19:dd:d9:dd:c25:c25:94de:3506
82c19:dd:d9:dd:c25:c25:94de:3507/1282c19:dd:d9:dd:c25:c25:94de:3507
92c19:dd:d9:dd:c25:c25:94de:3508/1282c19:dd:d9:dd:c25:c25:94de:3508
102c19:dd:d9:dd:c25:c25:94de:3509/1282c19:dd:d9:dd:c25:c25:94de:3509
112c19:dd:d9:dd:c25:c25:94de:350a/1282c19:dd:d9:dd:c25:c25:94de:350a
122c19:dd:d9:dd:c25:c25:94de:350b/1282c19:dd:d9:dd:c25:c25:94de:350b
132c19:dd:d9:dd:c25:c25:94de:350c/1282c19:dd:d9:dd:c25:c25:94de:350c
142c19:dd:d9:dd:c25:c25:94de:350d/1282c19:dd:d9:dd:c25:c25:94de:350d
152c19:dd:d9:dd:c25:c25:94de:350e/1282c19:dd:d9:dd:c25:c25:94de:350e
162c19:dd:d9:dd:c25:c25:94de:350f/1282c19:dd:d9:dd:c25:c25:94de:350f
172c19:dd:d9:dd:c25:c25:94de:3510/1282c19:dd:d9:dd:c25:c25:94de:3510
182c19:dd:d9:dd:c25:c25:94de:3511/1282c19:dd:d9:dd:c25:c25:94de:3511
192c19:dd:d9:dd:c25:c25:94de:3512/1282c19:dd:d9:dd:c25:c25:94de:3512
202c19:dd:d9:dd:c25:c25:94de:3513/1282c19:dd:d9:dd:c25:c25:94de:3513
212c19:dd:d9:dd:c25:c25:94de:3514/1282c19:dd:d9:dd:c25:c25:94de:3514
222c19:dd:d9:dd:c25:c25:94de:3515/1282c19:dd:d9:dd:c25:c25:94de:3515
232c19:dd:d9:dd:c25:c25:94de:3516/1282c19:dd:d9:dd:c25:c25:94de:3516
242c19:dd:d9:dd:c25:c25:94de:3517/1282c19:dd:d9:dd:c25:c25:94de:3517
252c19:dd:d9:dd:c25:c25:94de:3518/1282c19:dd:d9:dd:c25:c25:94de:3518
262c19:dd:d9:dd:c25:c25:94de:3519/1282c19:dd:d9:dd:c25:c25:94de:3519
272c19:dd:d9:dd:c25:c25:94de:351a/1282c19:dd:d9:dd:c25:c25:94de:351a
282c19:dd:d9:dd:c25:c25:94de:351b/1282c19:dd:d9:dd:c25:c25:94de:351b
292c19:dd:d9:dd:c25:c25:94de:351c/1282c19:dd:d9:dd:c25:c25:94de:351c
302c19:dd:d9:dd:c25:c25:94de:351d/1282c19:dd:d9:dd:c25:c25:94de:351d
312c19:dd:d9:dd:c25:c25:94de:351e/1282c19:dd:d9:dd:c25:c25:94de:351e
322c19:dd:d9:dd:c25:c25:94de:351f/1282c19:dd:d9:dd:c25:c25:94de:351f
332c19:dd:d9:dd:c25:c25:94de:3520/1282c19:dd:d9:dd:c25:c25:94de:3520
342c19:dd:d9:dd:c25:c25:94de:3521/1282c19:dd:d9:dd:c25:c25:94de:3521
352c19:dd:d9:dd:c25:c25:94de:3522/1282c19:dd:d9:dd:c25:c25:94de:3522
362c19:dd:d9:dd:c25:c25:94de:3523/1282c19:dd:d9:dd:c25:c25:94de:3523
372c19:dd:d9:dd:c25:c25:94de:3524/1282c19:dd:d9:dd:c25:c25:94de:3524
382c19:dd:d9:dd:c25:c25:94de:3525/1282c19:dd:d9:dd:c25:c25:94de:3525
392c19:dd:d9:dd:c25:c25:94de:3526/1282c19:dd:d9:dd:c25:c25:94de:3526
402c19:dd:d9:dd:c25:c25:94de:3527/1282c19:dd:d9:dd:c25:c25:94de:3527
412c19:dd:d9:dd:c25:c25:94de:3528/1282c19:dd:d9:dd:c25:c25:94de:3528
422c19:dd:d9:dd:c25:c25:94de:3529/1282c19:dd:d9:dd:c25:c25:94de:3529
432c19:dd:d9:dd:c25:c25:94de:352a/1282c19:dd:d9:dd:c25:c25:94de:352a
442c19:dd:d9:dd:c25:c25:94de:352b/1282c19:dd:d9:dd:c25:c25:94de:352b
452c19:dd:d9:dd:c25:c25:94de:352c/1282c19:dd:d9:dd:c25:c25:94de:352c
462c19:dd:d9:dd:c25:c25:94de:352d/1282c19:dd:d9:dd:c25:c25:94de:352d
472c19:dd:d9:dd:c25:c25:94de:352e/1282c19:dd:d9:dd:c25:c25:94de:352e
482c19:dd:d9:dd:c25:c25:94de:352f/1282c19:dd:d9:dd:c25:c25:94de:352f
492c19:dd:d9:dd:c25:c25:94de:3530/1282c19:dd:d9:dd:c25:c25:94de:3530
502c19:dd:d9:dd:c25:c25:94de:3531/1282c19:dd:d9:dd:c25:c25:94de:3531
512c19:dd:d9:dd:c25:c25:94de:3532/1282c19:dd:d9:dd:c25:c25:94de:3532
522c19:dd:d9:dd:c25:c25:94de:3533/1282c19:dd:d9:dd:c25:c25:94de:3533
532c19:dd:d9:dd:c25:c25:94de:3534/1282c19:dd:d9:dd:c25:c25:94de:3534
542c19:dd:d9:dd:c25:c25:94de:3535/1282c19:dd:d9:dd:c25:c25:94de:3535
552c19:dd:d9:dd:c25:c25:94de:3536/1282c19:dd:d9:dd:c25:c25:94de:3536
562c19:dd:d9:dd:c25:c25:94de:3537/1282c19:dd:d9:dd:c25:c25:94de:3537
572c19:dd:d9:dd:c25:c25:94de:3538/1282c19:dd:d9:dd:c25:c25:94de:3538
582c19:dd:d9:dd:c25:c25:94de:3539/1282c19:dd:d9:dd:c25:c25:94de:3539
592c19:dd:d9:dd:c25:c25:94de:353a/1282c19:dd:d9:dd:c25:c25:94de:353a
602c19:dd:d9:dd:c25:c25:94de:353b/1282c19:dd:d9:dd:c25:c25:94de:353b
612c19:dd:d9:dd:c25:c25:94de:353c/1282c19:dd:d9:dd:c25:c25:94de:353c
622c19:dd:d9:dd:c25:c25:94de:353d/1282c19:dd:d9:dd:c25:c25:94de:353d
632c19:dd:d9:dd:c25:c25:94de:353e/1282c19:dd:d9:dd:c25:c25:94de:353e
642c19:dd:d9:dd:c25:c25:94de:353f/1282c19:dd:d9:dd:c25:c25:94de:353f
652c19:dd:d9:dd:c25:c25:94de:3540/1282c19:dd:d9:dd:c25:c25:94de:3540
662c19:dd:d9:dd:c25:c25:94de:3541/1282c19:dd:d9:dd:c25:c25:94de:3541
672c19:dd:d9:dd:c25:c25:94de:3542/1282c19:dd:d9:dd:c25:c25:94de:3542
682c19:dd:d9:dd:c25:c25:94de:3543/1282c19:dd:d9:dd:c25:c25:94de:3543
692c19:dd:d9:dd:c25:c25:94de:3544/1282c19:dd:d9:dd:c25:c25:94de:3544
702c19:dd:d9:dd:c25:c25:94de:3545/1282c19:dd:d9:dd:c25:c25:94de:3545
712c19:dd:d9:dd:c25:c25:94de:3546/1282c19:dd:d9:dd:c25:c25:94de:3546
722c19:dd:d9:dd:c25:c25:94de:3547/1282c19:dd:d9:dd:c25:c25:94de:3547
732c19:dd:d9:dd:c25:c25:94de:3548/1282c19:dd:d9:dd:c25:c25:94de:3548
742c19:dd:d9:dd:c25:c25:94de:3549/1282c19:dd:d9:dd:c25:c25:94de:3549
752c19:dd:d9:dd:c25:c25:94de:354a/1282c19:dd:d9:dd:c25:c25:94de:354a
762c19:dd:d9:dd:c25:c25:94de:354b/1282c19:dd:d9:dd:c25:c25:94de:354b
772c19:dd:d9:dd:c25:c25:94de:354c/1282c19:dd:d9:dd:c25:c25:94de:354c
782c19:dd:d9:dd:c25:c25:94de:354d/1282c19:dd:d9:dd:c25:c25:94de:354d
792c19:dd:d9:dd:c25:c25:94de:354e/1282c19:dd:d9:dd:c25:c25:94de:354e
802c19:dd:d9:dd:c25:c25:94de:354f/1282c19:dd:d9:dd:c25:c25:94de:354f
812c19:dd:d9:dd:c25:c25:94de:3550/1282c19:dd:d9:dd:c25:c25:94de:3550
822c19:dd:d9:dd:c25:c25:94de:3551/1282c19:dd:d9:dd:c25:c25:94de:3551
832c19:dd:d9:dd:c25:c25:94de:3552/1282c19:dd:d9:dd:c25:c25:94de:3552
842c19:dd:d9:dd:c25:c25:94de:3553/1282c19:dd:d9:dd:c25:c25:94de:3553
852c19:dd:d9:dd:c25:c25:94de:3554/1282c19:dd:d9:dd:c25:c25:94de:3554
862c19:dd:d9:dd:c25:c25:94de:3555/1282c19:dd:d9:dd:c25:c25:94de:3555
872c19:dd:d9:dd:c25:c25:94de:3556/1282c19:dd:d9:dd:c25:c25:94de:3556
882c19:dd:d9:dd:c25:c25:94de:3557/1282c19:dd:d9:dd:c25:c25:94de:3557
892c19:dd:d9:dd:c25:c25:94de:3558/1282c19:dd:d9:dd:c25:c25:94de:3558
902c19:dd:d9:dd:c25:c25:94de:3559/1282c19:dd:d9:dd:c25:c25:94de:3559
912c19:dd:d9:dd:c25:c25:94de:355a/1282c19:dd:d9:dd:c25:c25:94de:355a
922c19:dd:d9:dd:c25:c25:94de:355b/1282c19:dd:d9:dd:c25:c25:94de:355b
932c19:dd:d9:dd:c25:c25:94de:355c/1282c19:dd:d9:dd:c25:c25:94de:355c
942c19:dd:d9:dd:c25:c25:94de:355d/1282c19:dd:d9:dd:c25:c25:94de:355d
952c19:dd:d9:dd:c25:c25:94de:355e/1282c19:dd:d9:dd:c25:c25:94de:355e
962c19:dd:d9:dd:c25:c25:94de:355f/1282c19:dd:d9:dd:c25:c25:94de:355f
972c19:dd:d9:dd:c25:c25:94de:3560/1282c19:dd:d9:dd:c25:c25:94de:3560
982c19:dd:d9:dd:c25:c25:94de:3561/1282c19:dd:d9:dd:c25:c25:94de:3561
992c19:dd:d9:dd:c25:c25:94de:3562/1282c19:dd:d9:dd:c25:c25:94de:3562
1002c19:dd:d9:dd:c25:c25:94de:3563/1282c19:dd:d9:dd:c25:c25:94de:3563
1012c19:dd:d9:dd:c25:c25:94de:3564/1282c19:dd:d9:dd:c25:c25:94de:3564
1022c19:dd:d9:dd:c25:c25:94de:3565/1282c19:dd:d9:dd:c25:c25:94de:3565
1032c19:dd:d9:dd:c25:c25:94de:3566/1282c19:dd:d9:dd:c25:c25:94de:3566
1042c19:dd:d9:dd:c25:c25:94de:3567/1282c19:dd:d9:dd:c25:c25:94de:3567
1052c19:dd:d9:dd:c25:c25:94de:3568/1282c19:dd:d9:dd:c25:c25:94de:3568
1062c19:dd:d9:dd:c25:c25:94de:3569/1282c19:dd:d9:dd:c25:c25:94de:3569
1072c19:dd:d9:dd:c25:c25:94de:356a/1282c19:dd:d9:dd:c25:c25:94de:356a
1082c19:dd:d9:dd:c25:c25:94de:356b/1282c19:dd:d9:dd:c25:c25:94de:356b
1092c19:dd:d9:dd:c25:c25:94de:356c/1282c19:dd:d9:dd:c25:c25:94de:356c
1102c19:dd:d9:dd:c25:c25:94de:356d/1282c19:dd:d9:dd:c25:c25:94de:356d
1112c19:dd:d9:dd:c25:c25:94de:356e/1282c19:dd:d9:dd:c25:c25:94de:356e
1122c19:dd:d9:dd:c25:c25:94de:356f/1282c19:dd:d9:dd:c25:c25:94de:356f
1132c19:dd:d9:dd:c25:c25:94de:3570/1282c19:dd:d9:dd:c25:c25:94de:3570
1142c19:dd:d9:dd:c25:c25:94de:3571/1282c19:dd:d9:dd:c25:c25:94de:3571
1152c19:dd:d9:dd:c25:c25:94de:3572/1282c19:dd:d9:dd:c25:c25:94de:3572
1162c19:dd:d9:dd:c25:c25:94de:3573/1282c19:dd:d9:dd:c25:c25:94de:3573
1172c19:dd:d9:dd:c25:c25:94de:3574/1282c19:dd:d9:dd:c25:c25:94de:3574
1182c19:dd:d9:dd:c25:c25:94de:3575/1282c19:dd:d9:dd:c25:c25:94de:3575
1192c19:dd:d9:dd:c25:c25:94de:3576/1282c19:dd:d9:dd:c25:c25:94de:3576
1202c19:dd:d9:dd:c25:c25:94de:3577/1282c19:dd:d9:dd:c25:c25:94de:3577
1212c19:dd:d9:dd:c25:c25:94de:3578/1282c19:dd:d9:dd:c25:c25:94de:3578
1222c19:dd:d9:dd:c25:c25:94de:3579/1282c19:dd:d9:dd:c25:c25:94de:3579
1232c19:dd:d9:dd:c25:c25:94de:357a/1282c19:dd:d9:dd:c25:c25:94de:357a
1242c19:dd:d9:dd:c25:c25:94de:357b/1282c19:dd:d9:dd:c25:c25:94de:357b
1252c19:dd:d9:dd:c25:c25:94de:357c/1282c19:dd:d9:dd:c25:c25:94de:357c
1262c19:dd:d9:dd:c25:c25:94de:357d/1282c19:dd:d9:dd:c25:c25:94de:357d
1272c19:dd:d9:dd:c25:c25:94de:357e/1282c19:dd:d9:dd:c25:c25:94de:357e
1282c19:dd:d9:dd:c25:c25:94de:357f/1282c19:dd:d9:dd:c25:c25:94de:357f
1292c19:dd:d9:dd:c25:c25:94de:3580/1282c19:dd:d9:dd:c25:c25:94de:3580
1302c19:dd:d9:dd:c25:c25:94de:3581/1282c19:dd:d9:dd:c25:c25:94de:3581
1312c19:dd:d9:dd:c25:c25:94de:3582/1282c19:dd:d9:dd:c25:c25:94de:3582
1322c19:dd:d9:dd:c25:c25:94de:3583/1282c19:dd:d9:dd:c25:c25:94de:3583
1332c19:dd:d9:dd:c25:c25:94de:3584/1282c19:dd:d9:dd:c25:c25:94de:3584
1342c19:dd:d9:dd:c25:c25:94de:3585/1282c19:dd:d9:dd:c25:c25:94de:3585
1352c19:dd:d9:dd:c25:c25:94de:3586/1282c19:dd:d9:dd:c25:c25:94de:3586
1362c19:dd:d9:dd:c25:c25:94de:3587/1282c19:dd:d9:dd:c25:c25:94de:3587
1372c19:dd:d9:dd:c25:c25:94de:3588/1282c19:dd:d9:dd:c25:c25:94de:3588
1382c19:dd:d9:dd:c25:c25:94de:3589/1282c19:dd:d9:dd:c25:c25:94de:3589
1392c19:dd:d9:dd:c25:c25:94de:358a/1282c19:dd:d9:dd:c25:c25:94de:358a
1402c19:dd:d9:dd:c25:c25:94de:358b/1282c19:dd:d9:dd:c25:c25:94de:358b
1412c19:dd:d9:dd:c25:c25:94de:358c/1282c19:dd:d9:dd:c25:c25:94de:358c
1422c19:dd:d9:dd:c25:c25:94de:358d/1282c19:dd:d9:dd:c25:c25:94de:358d
1432c19:dd:d9:dd:c25:c25:94de:358e/1282c19:dd:d9:dd:c25:c25:94de:358e
1442c19:dd:d9:dd:c25:c25:94de:358f/1282c19:dd:d9:dd:c25:c25:94de:358f
1452c19:dd:d9:dd:c25:c25:94de:3590/1282c19:dd:d9:dd:c25:c25:94de:3590
1462c19:dd:d9:dd:c25:c25:94de:3591/1282c19:dd:d9:dd:c25:c25:94de:3591
1472c19:dd:d9:dd:c25:c25:94de:3592/1282c19:dd:d9:dd:c25:c25:94de:3592
1482c19:dd:d9:dd:c25:c25:94de:3593/1282c19:dd:d9:dd:c25:c25:94de:3593
1492c19:dd:d9:dd:c25:c25:94de:3594/1282c19:dd:d9:dd:c25:c25:94de:3594
1502c19:dd:d9:dd:c25:c25:94de:3595/1282c19:dd:d9:dd:c25:c25:94de:3595
1512c19:dd:d9:dd:c25:c25:94de:3596/1282c19:dd:d9:dd:c25:c25:94de:3596
1522c19:dd:d9:dd:c25:c25:94de:3597/1282c19:dd:d9:dd:c25:c25:94de:3597
1532c19:dd:d9:dd:c25:c25:94de:3598/1282c19:dd:d9:dd:c25:c25:94de:3598
1542c19:dd:d9:dd:c25:c25:94de:3599/1282c19:dd:d9:dd:c25:c25:94de:3599
1552c19:dd:d9:dd:c25:c25:94de:359a/1282c19:dd:d9:dd:c25:c25:94de:359a
1562c19:dd:d9:dd:c25:c25:94de:359b/1282c19:dd:d9:dd:c25:c25:94de:359b
1572c19:dd:d9:dd:c25:c25:94de:359c/1282c19:dd:d9:dd:c25:c25:94de:359c
1582c19:dd:d9:dd:c25:c25:94de:359d/1282c19:dd:d9:dd:c25:c25:94de:359d
1592c19:dd:d9:dd:c25:c25:94de:359e/1282c19:dd:d9:dd:c25:c25:94de:359e
1602c19:dd:d9:dd:c25:c25:94de:359f/1282c19:dd:d9:dd:c25:c25:94de:359f
1612c19:dd:d9:dd:c25:c25:94de:35a0/1282c19:dd:d9:dd:c25:c25:94de:35a0
1622c19:dd:d9:dd:c25:c25:94de:35a1/1282c19:dd:d9:dd:c25:c25:94de:35a1
1632c19:dd:d9:dd:c25:c25:94de:35a2/1282c19:dd:d9:dd:c25:c25:94de:35a2
1642c19:dd:d9:dd:c25:c25:94de:35a3/1282c19:dd:d9:dd:c25:c25:94de:35a3
1652c19:dd:d9:dd:c25:c25:94de:35a4/1282c19:dd:d9:dd:c25:c25:94de:35a4
1662c19:dd:d9:dd:c25:c25:94de:35a5/1282c19:dd:d9:dd:c25:c25:94de:35a5
1672c19:dd:d9:dd:c25:c25:94de:35a6/1282c19:dd:d9:dd:c25:c25:94de:35a6
1682c19:dd:d9:dd:c25:c25:94de:35a7/1282c19:dd:d9:dd:c25:c25:94de:35a7
1692c19:dd:d9:dd:c25:c25:94de:35a8/1282c19:dd:d9:dd:c25:c25:94de:35a8
1702c19:dd:d9:dd:c25:c25:94de:35a9/1282c19:dd:d9:dd:c25:c25:94de:35a9
1712c19:dd:d9:dd:c25:c25:94de:35aa/1282c19:dd:d9:dd:c25:c25:94de:35aa
1722c19:dd:d9:dd:c25:c25:94de:35ab/1282c19:dd:d9:dd:c25:c25:94de:35ab
1732c19:dd:d9:dd:c25:c25:94de:35ac/1282c19:dd:d9:dd:c25:c25:94de:35ac
1742c19:dd:d9:dd:c25:c25:94de:35ad/1282c19:dd:d9:dd:c25:c25:94de:35ad
1752c19:dd:d9:dd:c25:c25:94de:35ae/1282c19:dd:d9:dd:c25:c25:94de:35ae
1762c19:dd:d9:dd:c25:c25:94de:35af/1282c19:dd:d9:dd:c25:c25:94de:35af
1772c19:dd:d9:dd:c25:c25:94de:35b0/1282c19:dd:d9:dd:c25:c25:94de:35b0
1782c19:dd:d9:dd:c25:c25:94de:35b1/1282c19:dd:d9:dd:c25:c25:94de:35b1
1792c19:dd:d9:dd:c25:c25:94de:35b2/1282c19:dd:d9:dd:c25:c25:94de:35b2
1802c19:dd:d9:dd:c25:c25:94de:35b3/1282c19:dd:d9:dd:c25:c25:94de:35b3
1812c19:dd:d9:dd:c25:c25:94de:35b4/1282c19:dd:d9:dd:c25:c25:94de:35b4
1822c19:dd:d9:dd:c25:c25:94de:35b5/1282c19:dd:d9:dd:c25:c25:94de:35b5
1832c19:dd:d9:dd:c25:c25:94de:35b6/1282c19:dd:d9:dd:c25:c25:94de:35b6
1842c19:dd:d9:dd:c25:c25:94de:35b7/1282c19:dd:d9:dd:c25:c25:94de:35b7
1852c19:dd:d9:dd:c25:c25:94de:35b8/1282c19:dd:d9:dd:c25:c25:94de:35b8
1862c19:dd:d9:dd:c25:c25:94de:35b9/1282c19:dd:d9:dd:c25:c25:94de:35b9
1872c19:dd:d9:dd:c25:c25:94de:35ba/1282c19:dd:d9:dd:c25:c25:94de:35ba
1882c19:dd:d9:dd:c25:c25:94de:35bb/1282c19:dd:d9:dd:c25:c25:94de:35bb
1892c19:dd:d9:dd:c25:c25:94de:35bc/1282c19:dd:d9:dd:c25:c25:94de:35bc
1902c19:dd:d9:dd:c25:c25:94de:35bd/1282c19:dd:d9:dd:c25:c25:94de:35bd
1912c19:dd:d9:dd:c25:c25:94de:35be/1282c19:dd:d9:dd:c25:c25:94de:35be
1922c19:dd:d9:dd:c25:c25:94de:35bf/1282c19:dd:d9:dd:c25:c25:94de:35bf
1932c19:dd:d9:dd:c25:c25:94de:35c0/1282c19:dd:d9:dd:c25:c25:94de:35c0
1942c19:dd:d9:dd:c25:c25:94de:35c1/1282c19:dd:d9:dd:c25:c25:94de:35c1
1952c19:dd:d9:dd:c25:c25:94de:35c2/1282c19:dd:d9:dd:c25:c25:94de:35c2
1962c19:dd:d9:dd:c25:c25:94de:35c3/1282c19:dd:d9:dd:c25:c25:94de:35c3
1972c19:dd:d9:dd:c25:c25:94de:35c4/1282c19:dd:d9:dd:c25:c25:94de:35c4
1982c19:dd:d9:dd:c25:c25:94de:35c5/1282c19:dd:d9:dd:c25:c25:94de:35c5
1992c19:dd:d9:dd:c25:c25:94de:35c6/1282c19:dd:d9:dd:c25:c25:94de:35c6
2002c19:dd:d9:dd:c25:c25:94de:35c7/1282c19:dd:d9:dd:c25:c25:94de:35c7
2012c19:dd:d9:dd:c25:c25:94de:35c8/1282c19:dd:d9:dd:c25:c25:94de:35c8
2022c19:dd:d9:dd:c25:c25:94de:35c9/1282c19:dd:d9:dd:c25:c25:94de:35c9
2032c19:dd:d9:dd:c25:c25:94de:35ca/1282c19:dd:d9:dd:c25:c25:94de:35ca
2042c19:dd:d9:dd:c25:c25:94de:35cb/1282c19:dd:d9:dd:c25:c25:94de:35cb
2052c19:dd:d9:dd:c25:c25:94de:35cc/1282c19:dd:d9:dd:c25:c25:94de:35cc
2062c19:dd:d9:dd:c25:c25:94de:35cd/1282c19:dd:d9:dd:c25:c25:94de:35cd
2072c19:dd:d9:dd:c25:c25:94de:35ce/1282c19:dd:d9:dd:c25:c25:94de:35ce
2082c19:dd:d9:dd:c25:c25:94de:35cf/1282c19:dd:d9:dd:c25:c25:94de:35cf
2092c19:dd:d9:dd:c25:c25:94de:35d0/1282c19:dd:d9:dd:c25:c25:94de:35d0
2102c19:dd:d9:dd:c25:c25:94de:35d1/1282c19:dd:d9:dd:c25:c25:94de:35d1
2112c19:dd:d9:dd:c25:c25:94de:35d2/1282c19:dd:d9:dd:c25:c25:94de:35d2
2122c19:dd:d9:dd:c25:c25:94de:35d3/1282c19:dd:d9:dd:c25:c25:94de:35d3
2132c19:dd:d9:dd:c25:c25:94de:35d4/1282c19:dd:d9:dd:c25:c25:94de:35d4
2142c19:dd:d9:dd:c25:c25:94de:35d5/1282c19:dd:d9:dd:c25:c25:94de:35d5
2152c19:dd:d9:dd:c25:c25:94de:35d6/1282c19:dd:d9:dd:c25:c25:94de:35d6
2162c19:dd:d9:dd:c25:c25:94de:35d7/1282c19:dd:d9:dd:c25:c25:94de:35d7
2172c19:dd:d9:dd:c25:c25:94de:35d8/1282c19:dd:d9:dd:c25:c25:94de:35d8
2182c19:dd:d9:dd:c25:c25:94de:35d9/1282c19:dd:d9:dd:c25:c25:94de:35d9
2192c19:dd:d9:dd:c25:c25:94de:35da/1282c19:dd:d9:dd:c25:c25:94de:35da
2202c19:dd:d9:dd:c25:c25:94de:35db/1282c19:dd:d9:dd:c25:c25:94de:35db
2212c19:dd:d9:dd:c25:c25:94de:35dc/1282c19:dd:d9:dd:c25:c25:94de:35dc
2222c19:dd:d9:dd:c25:c25:94de:35dd/1282c19:dd:d9:dd:c25:c25:94de:35dd
2232c19:dd:d9:dd:c25:c25:94de:35de/1282c19:dd:d9:dd:c25:c25:94de:35de
2242c19:dd:d9:dd:c25:c25:94de:35df/1282c19:dd:d9:dd:c25:c25:94de:35df
2252c19:dd:d9:dd:c25:c25:94de:35e0/1282c19:dd:d9:dd:c25:c25:94de:35e0
2262c19:dd:d9:dd:c25:c25:94de:35e1/1282c19:dd:d9:dd:c25:c25:94de:35e1
2272c19:dd:d9:dd:c25:c25:94de:35e2/1282c19:dd:d9:dd:c25:c25:94de:35e2
2282c19:dd:d9:dd:c25:c25:94de:35e3/1282c19:dd:d9:dd:c25:c25:94de:35e3
2292c19:dd:d9:dd:c25:c25:94de:35e4/1282c19:dd:d9:dd:c25:c25:94de:35e4
2302c19:dd:d9:dd:c25:c25:94de:35e5/1282c19:dd:d9:dd:c25:c25:94de:35e5
2312c19:dd:d9:dd:c25:c25:94de:35e6/1282c19:dd:d9:dd:c25:c25:94de:35e6
2322c19:dd:d9:dd:c25:c25:94de:35e7/1282c19:dd:d9:dd:c25:c25:94de:35e7
2332c19:dd:d9:dd:c25:c25:94de:35e8/1282c19:dd:d9:dd:c25:c25:94de:35e8
2342c19:dd:d9:dd:c25:c25:94de:35e9/1282c19:dd:d9:dd:c25:c25:94de:35e9
2352c19:dd:d9:dd:c25:c25:94de:35ea/1282c19:dd:d9:dd:c25:c25:94de:35ea
2362c19:dd:d9:dd:c25:c25:94de:35eb/1282c19:dd:d9:dd:c25:c25:94de:35eb
2372c19:dd:d9:dd:c25:c25:94de:35ec/1282c19:dd:d9:dd:c25:c25:94de:35ec
2382c19:dd:d9:dd:c25:c25:94de:35ed/1282c19:dd:d9:dd:c25:c25:94de:35ed
2392c19:dd:d9:dd:c25:c25:94de:35ee/1282c19:dd:d9:dd:c25:c25:94de:35ee
2402c19:dd:d9:dd:c25:c25:94de:35ef/1282c19:dd:d9:dd:c25:c25:94de:35ef
2412c19:dd:d9:dd:c25:c25:94de:35f0/1282c19:dd:d9:dd:c25:c25:94de:35f0
2422c19:dd:d9:dd:c25:c25:94de:35f1/1282c19:dd:d9:dd:c25:c25:94de:35f1
2432c19:dd:d9:dd:c25:c25:94de:35f2/1282c19:dd:d9:dd:c25:c25:94de:35f2
2442c19:dd:d9:dd:c25:c25:94de:35f3/1282c19:dd:d9:dd:c25:c25:94de:35f3
2452c19:dd:d9:dd:c25:c25:94de:35f4/1282c19:dd:d9:dd:c25:c25:94de:35f4
2462c19:dd:d9:dd:c25:c25:94de:35f5/1282c19:dd:d9:dd:c25:c25:94de:35f5
2472c19:dd:d9:dd:c25:c25:94de:35f6/1282c19:dd:d9:dd:c25:c25:94de:35f6
2482c19:dd:d9:dd:c25:c25:94de:35f7/1282c19:dd:d9:dd:c25:c25:94de:35f7
2492c19:dd:d9:dd:c25:c25:94de:35f8/1282c19:dd:d9:dd:c25:c25:94de:35f8
2502c19:dd:d9:dd:c25:c25:94de:35f9/1282c19:dd:d9:dd:c25:c25:94de:35f9
2512c19:dd:d9:dd:c25:c25:94de:35fa/1282c19:dd:d9:dd:c25:c25:94de:35fa
2522c19:dd:d9:dd:c25:c25:94de:35fb/1282c19:dd:d9:dd:c25:c25:94de:35fb
2532c19:dd:d9:dd:c25:c25:94de:35fc/1282c19:dd:d9:dd:c25:c25:94de:35fc
2542c19:dd:d9:dd:c25:c25:94de:35fd/1282c19:dd:d9:dd:c25:c25:94de:35fd
2552c19:dd:d9:dd:c25:c25:94de:35fe/1282c19:dd:d9:dd:c25:c25:94de:35fe
2562c19:dd:d9:dd:c25:c25:94de:35ff/1282c19:dd:d9:dd:c25:c25:94de:35ff

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.