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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:4600/120
First address
2c19:dd:d9:dd:c25:c25:94de:4600
Last address
2c19:dd:d9:dd:c25:c25:94de:46ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:4600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.4.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:4600/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:4600/1282c19:dd:d9:dd:c25:c25:94de:4600
22c19:dd:d9:dd:c25:c25:94de:4601/1282c19:dd:d9:dd:c25:c25:94de:4601
32c19:dd:d9:dd:c25:c25:94de:4602/1282c19:dd:d9:dd:c25:c25:94de:4602
42c19:dd:d9:dd:c25:c25:94de:4603/1282c19:dd:d9:dd:c25:c25:94de:4603
52c19:dd:d9:dd:c25:c25:94de:4604/1282c19:dd:d9:dd:c25:c25:94de:4604
62c19:dd:d9:dd:c25:c25:94de:4605/1282c19:dd:d9:dd:c25:c25:94de:4605
72c19:dd:d9:dd:c25:c25:94de:4606/1282c19:dd:d9:dd:c25:c25:94de:4606
82c19:dd:d9:dd:c25:c25:94de:4607/1282c19:dd:d9:dd:c25:c25:94de:4607
92c19:dd:d9:dd:c25:c25:94de:4608/1282c19:dd:d9:dd:c25:c25:94de:4608
102c19:dd:d9:dd:c25:c25:94de:4609/1282c19:dd:d9:dd:c25:c25:94de:4609
112c19:dd:d9:dd:c25:c25:94de:460a/1282c19:dd:d9:dd:c25:c25:94de:460a
122c19:dd:d9:dd:c25:c25:94de:460b/1282c19:dd:d9:dd:c25:c25:94de:460b
132c19:dd:d9:dd:c25:c25:94de:460c/1282c19:dd:d9:dd:c25:c25:94de:460c
142c19:dd:d9:dd:c25:c25:94de:460d/1282c19:dd:d9:dd:c25:c25:94de:460d
152c19:dd:d9:dd:c25:c25:94de:460e/1282c19:dd:d9:dd:c25:c25:94de:460e
162c19:dd:d9:dd:c25:c25:94de:460f/1282c19:dd:d9:dd:c25:c25:94de:460f
172c19:dd:d9:dd:c25:c25:94de:4610/1282c19:dd:d9:dd:c25:c25:94de:4610
182c19:dd:d9:dd:c25:c25:94de:4611/1282c19:dd:d9:dd:c25:c25:94de:4611
192c19:dd:d9:dd:c25:c25:94de:4612/1282c19:dd:d9:dd:c25:c25:94de:4612
202c19:dd:d9:dd:c25:c25:94de:4613/1282c19:dd:d9:dd:c25:c25:94de:4613
212c19:dd:d9:dd:c25:c25:94de:4614/1282c19:dd:d9:dd:c25:c25:94de:4614
222c19:dd:d9:dd:c25:c25:94de:4615/1282c19:dd:d9:dd:c25:c25:94de:4615
232c19:dd:d9:dd:c25:c25:94de:4616/1282c19:dd:d9:dd:c25:c25:94de:4616
242c19:dd:d9:dd:c25:c25:94de:4617/1282c19:dd:d9:dd:c25:c25:94de:4617
252c19:dd:d9:dd:c25:c25:94de:4618/1282c19:dd:d9:dd:c25:c25:94de:4618
262c19:dd:d9:dd:c25:c25:94de:4619/1282c19:dd:d9:dd:c25:c25:94de:4619
272c19:dd:d9:dd:c25:c25:94de:461a/1282c19:dd:d9:dd:c25:c25:94de:461a
282c19:dd:d9:dd:c25:c25:94de:461b/1282c19:dd:d9:dd:c25:c25:94de:461b
292c19:dd:d9:dd:c25:c25:94de:461c/1282c19:dd:d9:dd:c25:c25:94de:461c
302c19:dd:d9:dd:c25:c25:94de:461d/1282c19:dd:d9:dd:c25:c25:94de:461d
312c19:dd:d9:dd:c25:c25:94de:461e/1282c19:dd:d9:dd:c25:c25:94de:461e
322c19:dd:d9:dd:c25:c25:94de:461f/1282c19:dd:d9:dd:c25:c25:94de:461f
332c19:dd:d9:dd:c25:c25:94de:4620/1282c19:dd:d9:dd:c25:c25:94de:4620
342c19:dd:d9:dd:c25:c25:94de:4621/1282c19:dd:d9:dd:c25:c25:94de:4621
352c19:dd:d9:dd:c25:c25:94de:4622/1282c19:dd:d9:dd:c25:c25:94de:4622
362c19:dd:d9:dd:c25:c25:94de:4623/1282c19:dd:d9:dd:c25:c25:94de:4623
372c19:dd:d9:dd:c25:c25:94de:4624/1282c19:dd:d9:dd:c25:c25:94de:4624
382c19:dd:d9:dd:c25:c25:94de:4625/1282c19:dd:d9:dd:c25:c25:94de:4625
392c19:dd:d9:dd:c25:c25:94de:4626/1282c19:dd:d9:dd:c25:c25:94de:4626
402c19:dd:d9:dd:c25:c25:94de:4627/1282c19:dd:d9:dd:c25:c25:94de:4627
412c19:dd:d9:dd:c25:c25:94de:4628/1282c19:dd:d9:dd:c25:c25:94de:4628
422c19:dd:d9:dd:c25:c25:94de:4629/1282c19:dd:d9:dd:c25:c25:94de:4629
432c19:dd:d9:dd:c25:c25:94de:462a/1282c19:dd:d9:dd:c25:c25:94de:462a
442c19:dd:d9:dd:c25:c25:94de:462b/1282c19:dd:d9:dd:c25:c25:94de:462b
452c19:dd:d9:dd:c25:c25:94de:462c/1282c19:dd:d9:dd:c25:c25:94de:462c
462c19:dd:d9:dd:c25:c25:94de:462d/1282c19:dd:d9:dd:c25:c25:94de:462d
472c19:dd:d9:dd:c25:c25:94de:462e/1282c19:dd:d9:dd:c25:c25:94de:462e
482c19:dd:d9:dd:c25:c25:94de:462f/1282c19:dd:d9:dd:c25:c25:94de:462f
492c19:dd:d9:dd:c25:c25:94de:4630/1282c19:dd:d9:dd:c25:c25:94de:4630
502c19:dd:d9:dd:c25:c25:94de:4631/1282c19:dd:d9:dd:c25:c25:94de:4631
512c19:dd:d9:dd:c25:c25:94de:4632/1282c19:dd:d9:dd:c25:c25:94de:4632
522c19:dd:d9:dd:c25:c25:94de:4633/1282c19:dd:d9:dd:c25:c25:94de:4633
532c19:dd:d9:dd:c25:c25:94de:4634/1282c19:dd:d9:dd:c25:c25:94de:4634
542c19:dd:d9:dd:c25:c25:94de:4635/1282c19:dd:d9:dd:c25:c25:94de:4635
552c19:dd:d9:dd:c25:c25:94de:4636/1282c19:dd:d9:dd:c25:c25:94de:4636
562c19:dd:d9:dd:c25:c25:94de:4637/1282c19:dd:d9:dd:c25:c25:94de:4637
572c19:dd:d9:dd:c25:c25:94de:4638/1282c19:dd:d9:dd:c25:c25:94de:4638
582c19:dd:d9:dd:c25:c25:94de:4639/1282c19:dd:d9:dd:c25:c25:94de:4639
592c19:dd:d9:dd:c25:c25:94de:463a/1282c19:dd:d9:dd:c25:c25:94de:463a
602c19:dd:d9:dd:c25:c25:94de:463b/1282c19:dd:d9:dd:c25:c25:94de:463b
612c19:dd:d9:dd:c25:c25:94de:463c/1282c19:dd:d9:dd:c25:c25:94de:463c
622c19:dd:d9:dd:c25:c25:94de:463d/1282c19:dd:d9:dd:c25:c25:94de:463d
632c19:dd:d9:dd:c25:c25:94de:463e/1282c19:dd:d9:dd:c25:c25:94de:463e
642c19:dd:d9:dd:c25:c25:94de:463f/1282c19:dd:d9:dd:c25:c25:94de:463f
652c19:dd:d9:dd:c25:c25:94de:4640/1282c19:dd:d9:dd:c25:c25:94de:4640
662c19:dd:d9:dd:c25:c25:94de:4641/1282c19:dd:d9:dd:c25:c25:94de:4641
672c19:dd:d9:dd:c25:c25:94de:4642/1282c19:dd:d9:dd:c25:c25:94de:4642
682c19:dd:d9:dd:c25:c25:94de:4643/1282c19:dd:d9:dd:c25:c25:94de:4643
692c19:dd:d9:dd:c25:c25:94de:4644/1282c19:dd:d9:dd:c25:c25:94de:4644
702c19:dd:d9:dd:c25:c25:94de:4645/1282c19:dd:d9:dd:c25:c25:94de:4645
712c19:dd:d9:dd:c25:c25:94de:4646/1282c19:dd:d9:dd:c25:c25:94de:4646
722c19:dd:d9:dd:c25:c25:94de:4647/1282c19:dd:d9:dd:c25:c25:94de:4647
732c19:dd:d9:dd:c25:c25:94de:4648/1282c19:dd:d9:dd:c25:c25:94de:4648
742c19:dd:d9:dd:c25:c25:94de:4649/1282c19:dd:d9:dd:c25:c25:94de:4649
752c19:dd:d9:dd:c25:c25:94de:464a/1282c19:dd:d9:dd:c25:c25:94de:464a
762c19:dd:d9:dd:c25:c25:94de:464b/1282c19:dd:d9:dd:c25:c25:94de:464b
772c19:dd:d9:dd:c25:c25:94de:464c/1282c19:dd:d9:dd:c25:c25:94de:464c
782c19:dd:d9:dd:c25:c25:94de:464d/1282c19:dd:d9:dd:c25:c25:94de:464d
792c19:dd:d9:dd:c25:c25:94de:464e/1282c19:dd:d9:dd:c25:c25:94de:464e
802c19:dd:d9:dd:c25:c25:94de:464f/1282c19:dd:d9:dd:c25:c25:94de:464f
812c19:dd:d9:dd:c25:c25:94de:4650/1282c19:dd:d9:dd:c25:c25:94de:4650
822c19:dd:d9:dd:c25:c25:94de:4651/1282c19:dd:d9:dd:c25:c25:94de:4651
832c19:dd:d9:dd:c25:c25:94de:4652/1282c19:dd:d9:dd:c25:c25:94de:4652
842c19:dd:d9:dd:c25:c25:94de:4653/1282c19:dd:d9:dd:c25:c25:94de:4653
852c19:dd:d9:dd:c25:c25:94de:4654/1282c19:dd:d9:dd:c25:c25:94de:4654
862c19:dd:d9:dd:c25:c25:94de:4655/1282c19:dd:d9:dd:c25:c25:94de:4655
872c19:dd:d9:dd:c25:c25:94de:4656/1282c19:dd:d9:dd:c25:c25:94de:4656
882c19:dd:d9:dd:c25:c25:94de:4657/1282c19:dd:d9:dd:c25:c25:94de:4657
892c19:dd:d9:dd:c25:c25:94de:4658/1282c19:dd:d9:dd:c25:c25:94de:4658
902c19:dd:d9:dd:c25:c25:94de:4659/1282c19:dd:d9:dd:c25:c25:94de:4659
912c19:dd:d9:dd:c25:c25:94de:465a/1282c19:dd:d9:dd:c25:c25:94de:465a
922c19:dd:d9:dd:c25:c25:94de:465b/1282c19:dd:d9:dd:c25:c25:94de:465b
932c19:dd:d9:dd:c25:c25:94de:465c/1282c19:dd:d9:dd:c25:c25:94de:465c
942c19:dd:d9:dd:c25:c25:94de:465d/1282c19:dd:d9:dd:c25:c25:94de:465d
952c19:dd:d9:dd:c25:c25:94de:465e/1282c19:dd:d9:dd:c25:c25:94de:465e
962c19:dd:d9:dd:c25:c25:94de:465f/1282c19:dd:d9:dd:c25:c25:94de:465f
972c19:dd:d9:dd:c25:c25:94de:4660/1282c19:dd:d9:dd:c25:c25:94de:4660
982c19:dd:d9:dd:c25:c25:94de:4661/1282c19:dd:d9:dd:c25:c25:94de:4661
992c19:dd:d9:dd:c25:c25:94de:4662/1282c19:dd:d9:dd:c25:c25:94de:4662
1002c19:dd:d9:dd:c25:c25:94de:4663/1282c19:dd:d9:dd:c25:c25:94de:4663
1012c19:dd:d9:dd:c25:c25:94de:4664/1282c19:dd:d9:dd:c25:c25:94de:4664
1022c19:dd:d9:dd:c25:c25:94de:4665/1282c19:dd:d9:dd:c25:c25:94de:4665
1032c19:dd:d9:dd:c25:c25:94de:4666/1282c19:dd:d9:dd:c25:c25:94de:4666
1042c19:dd:d9:dd:c25:c25:94de:4667/1282c19:dd:d9:dd:c25:c25:94de:4667
1052c19:dd:d9:dd:c25:c25:94de:4668/1282c19:dd:d9:dd:c25:c25:94de:4668
1062c19:dd:d9:dd:c25:c25:94de:4669/1282c19:dd:d9:dd:c25:c25:94de:4669
1072c19:dd:d9:dd:c25:c25:94de:466a/1282c19:dd:d9:dd:c25:c25:94de:466a
1082c19:dd:d9:dd:c25:c25:94de:466b/1282c19:dd:d9:dd:c25:c25:94de:466b
1092c19:dd:d9:dd:c25:c25:94de:466c/1282c19:dd:d9:dd:c25:c25:94de:466c
1102c19:dd:d9:dd:c25:c25:94de:466d/1282c19:dd:d9:dd:c25:c25:94de:466d
1112c19:dd:d9:dd:c25:c25:94de:466e/1282c19:dd:d9:dd:c25:c25:94de:466e
1122c19:dd:d9:dd:c25:c25:94de:466f/1282c19:dd:d9:dd:c25:c25:94de:466f
1132c19:dd:d9:dd:c25:c25:94de:4670/1282c19:dd:d9:dd:c25:c25:94de:4670
1142c19:dd:d9:dd:c25:c25:94de:4671/1282c19:dd:d9:dd:c25:c25:94de:4671
1152c19:dd:d9:dd:c25:c25:94de:4672/1282c19:dd:d9:dd:c25:c25:94de:4672
1162c19:dd:d9:dd:c25:c25:94de:4673/1282c19:dd:d9:dd:c25:c25:94de:4673
1172c19:dd:d9:dd:c25:c25:94de:4674/1282c19:dd:d9:dd:c25:c25:94de:4674
1182c19:dd:d9:dd:c25:c25:94de:4675/1282c19:dd:d9:dd:c25:c25:94de:4675
1192c19:dd:d9:dd:c25:c25:94de:4676/1282c19:dd:d9:dd:c25:c25:94de:4676
1202c19:dd:d9:dd:c25:c25:94de:4677/1282c19:dd:d9:dd:c25:c25:94de:4677
1212c19:dd:d9:dd:c25:c25:94de:4678/1282c19:dd:d9:dd:c25:c25:94de:4678
1222c19:dd:d9:dd:c25:c25:94de:4679/1282c19:dd:d9:dd:c25:c25:94de:4679
1232c19:dd:d9:dd:c25:c25:94de:467a/1282c19:dd:d9:dd:c25:c25:94de:467a
1242c19:dd:d9:dd:c25:c25:94de:467b/1282c19:dd:d9:dd:c25:c25:94de:467b
1252c19:dd:d9:dd:c25:c25:94de:467c/1282c19:dd:d9:dd:c25:c25:94de:467c
1262c19:dd:d9:dd:c25:c25:94de:467d/1282c19:dd:d9:dd:c25:c25:94de:467d
1272c19:dd:d9:dd:c25:c25:94de:467e/1282c19:dd:d9:dd:c25:c25:94de:467e
1282c19:dd:d9:dd:c25:c25:94de:467f/1282c19:dd:d9:dd:c25:c25:94de:467f
1292c19:dd:d9:dd:c25:c25:94de:4680/1282c19:dd:d9:dd:c25:c25:94de:4680
1302c19:dd:d9:dd:c25:c25:94de:4681/1282c19:dd:d9:dd:c25:c25:94de:4681
1312c19:dd:d9:dd:c25:c25:94de:4682/1282c19:dd:d9:dd:c25:c25:94de:4682
1322c19:dd:d9:dd:c25:c25:94de:4683/1282c19:dd:d9:dd:c25:c25:94de:4683
1332c19:dd:d9:dd:c25:c25:94de:4684/1282c19:dd:d9:dd:c25:c25:94de:4684
1342c19:dd:d9:dd:c25:c25:94de:4685/1282c19:dd:d9:dd:c25:c25:94de:4685
1352c19:dd:d9:dd:c25:c25:94de:4686/1282c19:dd:d9:dd:c25:c25:94de:4686
1362c19:dd:d9:dd:c25:c25:94de:4687/1282c19:dd:d9:dd:c25:c25:94de:4687
1372c19:dd:d9:dd:c25:c25:94de:4688/1282c19:dd:d9:dd:c25:c25:94de:4688
1382c19:dd:d9:dd:c25:c25:94de:4689/1282c19:dd:d9:dd:c25:c25:94de:4689
1392c19:dd:d9:dd:c25:c25:94de:468a/1282c19:dd:d9:dd:c25:c25:94de:468a
1402c19:dd:d9:dd:c25:c25:94de:468b/1282c19:dd:d9:dd:c25:c25:94de:468b
1412c19:dd:d9:dd:c25:c25:94de:468c/1282c19:dd:d9:dd:c25:c25:94de:468c
1422c19:dd:d9:dd:c25:c25:94de:468d/1282c19:dd:d9:dd:c25:c25:94de:468d
1432c19:dd:d9:dd:c25:c25:94de:468e/1282c19:dd:d9:dd:c25:c25:94de:468e
1442c19:dd:d9:dd:c25:c25:94de:468f/1282c19:dd:d9:dd:c25:c25:94de:468f
1452c19:dd:d9:dd:c25:c25:94de:4690/1282c19:dd:d9:dd:c25:c25:94de:4690
1462c19:dd:d9:dd:c25:c25:94de:4691/1282c19:dd:d9:dd:c25:c25:94de:4691
1472c19:dd:d9:dd:c25:c25:94de:4692/1282c19:dd:d9:dd:c25:c25:94de:4692
1482c19:dd:d9:dd:c25:c25:94de:4693/1282c19:dd:d9:dd:c25:c25:94de:4693
1492c19:dd:d9:dd:c25:c25:94de:4694/1282c19:dd:d9:dd:c25:c25:94de:4694
1502c19:dd:d9:dd:c25:c25:94de:4695/1282c19:dd:d9:dd:c25:c25:94de:4695
1512c19:dd:d9:dd:c25:c25:94de:4696/1282c19:dd:d9:dd:c25:c25:94de:4696
1522c19:dd:d9:dd:c25:c25:94de:4697/1282c19:dd:d9:dd:c25:c25:94de:4697
1532c19:dd:d9:dd:c25:c25:94de:4698/1282c19:dd:d9:dd:c25:c25:94de:4698
1542c19:dd:d9:dd:c25:c25:94de:4699/1282c19:dd:d9:dd:c25:c25:94de:4699
1552c19:dd:d9:dd:c25:c25:94de:469a/1282c19:dd:d9:dd:c25:c25:94de:469a
1562c19:dd:d9:dd:c25:c25:94de:469b/1282c19:dd:d9:dd:c25:c25:94de:469b
1572c19:dd:d9:dd:c25:c25:94de:469c/1282c19:dd:d9:dd:c25:c25:94de:469c
1582c19:dd:d9:dd:c25:c25:94de:469d/1282c19:dd:d9:dd:c25:c25:94de:469d
1592c19:dd:d9:dd:c25:c25:94de:469e/1282c19:dd:d9:dd:c25:c25:94de:469e
1602c19:dd:d9:dd:c25:c25:94de:469f/1282c19:dd:d9:dd:c25:c25:94de:469f
1612c19:dd:d9:dd:c25:c25:94de:46a0/1282c19:dd:d9:dd:c25:c25:94de:46a0
1622c19:dd:d9:dd:c25:c25:94de:46a1/1282c19:dd:d9:dd:c25:c25:94de:46a1
1632c19:dd:d9:dd:c25:c25:94de:46a2/1282c19:dd:d9:dd:c25:c25:94de:46a2
1642c19:dd:d9:dd:c25:c25:94de:46a3/1282c19:dd:d9:dd:c25:c25:94de:46a3
1652c19:dd:d9:dd:c25:c25:94de:46a4/1282c19:dd:d9:dd:c25:c25:94de:46a4
1662c19:dd:d9:dd:c25:c25:94de:46a5/1282c19:dd:d9:dd:c25:c25:94de:46a5
1672c19:dd:d9:dd:c25:c25:94de:46a6/1282c19:dd:d9:dd:c25:c25:94de:46a6
1682c19:dd:d9:dd:c25:c25:94de:46a7/1282c19:dd:d9:dd:c25:c25:94de:46a7
1692c19:dd:d9:dd:c25:c25:94de:46a8/1282c19:dd:d9:dd:c25:c25:94de:46a8
1702c19:dd:d9:dd:c25:c25:94de:46a9/1282c19:dd:d9:dd:c25:c25:94de:46a9
1712c19:dd:d9:dd:c25:c25:94de:46aa/1282c19:dd:d9:dd:c25:c25:94de:46aa
1722c19:dd:d9:dd:c25:c25:94de:46ab/1282c19:dd:d9:dd:c25:c25:94de:46ab
1732c19:dd:d9:dd:c25:c25:94de:46ac/1282c19:dd:d9:dd:c25:c25:94de:46ac
1742c19:dd:d9:dd:c25:c25:94de:46ad/1282c19:dd:d9:dd:c25:c25:94de:46ad
1752c19:dd:d9:dd:c25:c25:94de:46ae/1282c19:dd:d9:dd:c25:c25:94de:46ae
1762c19:dd:d9:dd:c25:c25:94de:46af/1282c19:dd:d9:dd:c25:c25:94de:46af
1772c19:dd:d9:dd:c25:c25:94de:46b0/1282c19:dd:d9:dd:c25:c25:94de:46b0
1782c19:dd:d9:dd:c25:c25:94de:46b1/1282c19:dd:d9:dd:c25:c25:94de:46b1
1792c19:dd:d9:dd:c25:c25:94de:46b2/1282c19:dd:d9:dd:c25:c25:94de:46b2
1802c19:dd:d9:dd:c25:c25:94de:46b3/1282c19:dd:d9:dd:c25:c25:94de:46b3
1812c19:dd:d9:dd:c25:c25:94de:46b4/1282c19:dd:d9:dd:c25:c25:94de:46b4
1822c19:dd:d9:dd:c25:c25:94de:46b5/1282c19:dd:d9:dd:c25:c25:94de:46b5
1832c19:dd:d9:dd:c25:c25:94de:46b6/1282c19:dd:d9:dd:c25:c25:94de:46b6
1842c19:dd:d9:dd:c25:c25:94de:46b7/1282c19:dd:d9:dd:c25:c25:94de:46b7
1852c19:dd:d9:dd:c25:c25:94de:46b8/1282c19:dd:d9:dd:c25:c25:94de:46b8
1862c19:dd:d9:dd:c25:c25:94de:46b9/1282c19:dd:d9:dd:c25:c25:94de:46b9
1872c19:dd:d9:dd:c25:c25:94de:46ba/1282c19:dd:d9:dd:c25:c25:94de:46ba
1882c19:dd:d9:dd:c25:c25:94de:46bb/1282c19:dd:d9:dd:c25:c25:94de:46bb
1892c19:dd:d9:dd:c25:c25:94de:46bc/1282c19:dd:d9:dd:c25:c25:94de:46bc
1902c19:dd:d9:dd:c25:c25:94de:46bd/1282c19:dd:d9:dd:c25:c25:94de:46bd
1912c19:dd:d9:dd:c25:c25:94de:46be/1282c19:dd:d9:dd:c25:c25:94de:46be
1922c19:dd:d9:dd:c25:c25:94de:46bf/1282c19:dd:d9:dd:c25:c25:94de:46bf
1932c19:dd:d9:dd:c25:c25:94de:46c0/1282c19:dd:d9:dd:c25:c25:94de:46c0
1942c19:dd:d9:dd:c25:c25:94de:46c1/1282c19:dd:d9:dd:c25:c25:94de:46c1
1952c19:dd:d9:dd:c25:c25:94de:46c2/1282c19:dd:d9:dd:c25:c25:94de:46c2
1962c19:dd:d9:dd:c25:c25:94de:46c3/1282c19:dd:d9:dd:c25:c25:94de:46c3
1972c19:dd:d9:dd:c25:c25:94de:46c4/1282c19:dd:d9:dd:c25:c25:94de:46c4
1982c19:dd:d9:dd:c25:c25:94de:46c5/1282c19:dd:d9:dd:c25:c25:94de:46c5
1992c19:dd:d9:dd:c25:c25:94de:46c6/1282c19:dd:d9:dd:c25:c25:94de:46c6
2002c19:dd:d9:dd:c25:c25:94de:46c7/1282c19:dd:d9:dd:c25:c25:94de:46c7
2012c19:dd:d9:dd:c25:c25:94de:46c8/1282c19:dd:d9:dd:c25:c25:94de:46c8
2022c19:dd:d9:dd:c25:c25:94de:46c9/1282c19:dd:d9:dd:c25:c25:94de:46c9
2032c19:dd:d9:dd:c25:c25:94de:46ca/1282c19:dd:d9:dd:c25:c25:94de:46ca
2042c19:dd:d9:dd:c25:c25:94de:46cb/1282c19:dd:d9:dd:c25:c25:94de:46cb
2052c19:dd:d9:dd:c25:c25:94de:46cc/1282c19:dd:d9:dd:c25:c25:94de:46cc
2062c19:dd:d9:dd:c25:c25:94de:46cd/1282c19:dd:d9:dd:c25:c25:94de:46cd
2072c19:dd:d9:dd:c25:c25:94de:46ce/1282c19:dd:d9:dd:c25:c25:94de:46ce
2082c19:dd:d9:dd:c25:c25:94de:46cf/1282c19:dd:d9:dd:c25:c25:94de:46cf
2092c19:dd:d9:dd:c25:c25:94de:46d0/1282c19:dd:d9:dd:c25:c25:94de:46d0
2102c19:dd:d9:dd:c25:c25:94de:46d1/1282c19:dd:d9:dd:c25:c25:94de:46d1
2112c19:dd:d9:dd:c25:c25:94de:46d2/1282c19:dd:d9:dd:c25:c25:94de:46d2
2122c19:dd:d9:dd:c25:c25:94de:46d3/1282c19:dd:d9:dd:c25:c25:94de:46d3
2132c19:dd:d9:dd:c25:c25:94de:46d4/1282c19:dd:d9:dd:c25:c25:94de:46d4
2142c19:dd:d9:dd:c25:c25:94de:46d5/1282c19:dd:d9:dd:c25:c25:94de:46d5
2152c19:dd:d9:dd:c25:c25:94de:46d6/1282c19:dd:d9:dd:c25:c25:94de:46d6
2162c19:dd:d9:dd:c25:c25:94de:46d7/1282c19:dd:d9:dd:c25:c25:94de:46d7
2172c19:dd:d9:dd:c25:c25:94de:46d8/1282c19:dd:d9:dd:c25:c25:94de:46d8
2182c19:dd:d9:dd:c25:c25:94de:46d9/1282c19:dd:d9:dd:c25:c25:94de:46d9
2192c19:dd:d9:dd:c25:c25:94de:46da/1282c19:dd:d9:dd:c25:c25:94de:46da
2202c19:dd:d9:dd:c25:c25:94de:46db/1282c19:dd:d9:dd:c25:c25:94de:46db
2212c19:dd:d9:dd:c25:c25:94de:46dc/1282c19:dd:d9:dd:c25:c25:94de:46dc
2222c19:dd:d9:dd:c25:c25:94de:46dd/1282c19:dd:d9:dd:c25:c25:94de:46dd
2232c19:dd:d9:dd:c25:c25:94de:46de/1282c19:dd:d9:dd:c25:c25:94de:46de
2242c19:dd:d9:dd:c25:c25:94de:46df/1282c19:dd:d9:dd:c25:c25:94de:46df
2252c19:dd:d9:dd:c25:c25:94de:46e0/1282c19:dd:d9:dd:c25:c25:94de:46e0
2262c19:dd:d9:dd:c25:c25:94de:46e1/1282c19:dd:d9:dd:c25:c25:94de:46e1
2272c19:dd:d9:dd:c25:c25:94de:46e2/1282c19:dd:d9:dd:c25:c25:94de:46e2
2282c19:dd:d9:dd:c25:c25:94de:46e3/1282c19:dd:d9:dd:c25:c25:94de:46e3
2292c19:dd:d9:dd:c25:c25:94de:46e4/1282c19:dd:d9:dd:c25:c25:94de:46e4
2302c19:dd:d9:dd:c25:c25:94de:46e5/1282c19:dd:d9:dd:c25:c25:94de:46e5
2312c19:dd:d9:dd:c25:c25:94de:46e6/1282c19:dd:d9:dd:c25:c25:94de:46e6
2322c19:dd:d9:dd:c25:c25:94de:46e7/1282c19:dd:d9:dd:c25:c25:94de:46e7
2332c19:dd:d9:dd:c25:c25:94de:46e8/1282c19:dd:d9:dd:c25:c25:94de:46e8
2342c19:dd:d9:dd:c25:c25:94de:46e9/1282c19:dd:d9:dd:c25:c25:94de:46e9
2352c19:dd:d9:dd:c25:c25:94de:46ea/1282c19:dd:d9:dd:c25:c25:94de:46ea
2362c19:dd:d9:dd:c25:c25:94de:46eb/1282c19:dd:d9:dd:c25:c25:94de:46eb
2372c19:dd:d9:dd:c25:c25:94de:46ec/1282c19:dd:d9:dd:c25:c25:94de:46ec
2382c19:dd:d9:dd:c25:c25:94de:46ed/1282c19:dd:d9:dd:c25:c25:94de:46ed
2392c19:dd:d9:dd:c25:c25:94de:46ee/1282c19:dd:d9:dd:c25:c25:94de:46ee
2402c19:dd:d9:dd:c25:c25:94de:46ef/1282c19:dd:d9:dd:c25:c25:94de:46ef
2412c19:dd:d9:dd:c25:c25:94de:46f0/1282c19:dd:d9:dd:c25:c25:94de:46f0
2422c19:dd:d9:dd:c25:c25:94de:46f1/1282c19:dd:d9:dd:c25:c25:94de:46f1
2432c19:dd:d9:dd:c25:c25:94de:46f2/1282c19:dd:d9:dd:c25:c25:94de:46f2
2442c19:dd:d9:dd:c25:c25:94de:46f3/1282c19:dd:d9:dd:c25:c25:94de:46f3
2452c19:dd:d9:dd:c25:c25:94de:46f4/1282c19:dd:d9:dd:c25:c25:94de:46f4
2462c19:dd:d9:dd:c25:c25:94de:46f5/1282c19:dd:d9:dd:c25:c25:94de:46f5
2472c19:dd:d9:dd:c25:c25:94de:46f6/1282c19:dd:d9:dd:c25:c25:94de:46f6
2482c19:dd:d9:dd:c25:c25:94de:46f7/1282c19:dd:d9:dd:c25:c25:94de:46f7
2492c19:dd:d9:dd:c25:c25:94de:46f8/1282c19:dd:d9:dd:c25:c25:94de:46f8
2502c19:dd:d9:dd:c25:c25:94de:46f9/1282c19:dd:d9:dd:c25:c25:94de:46f9
2512c19:dd:d9:dd:c25:c25:94de:46fa/1282c19:dd:d9:dd:c25:c25:94de:46fa
2522c19:dd:d9:dd:c25:c25:94de:46fb/1282c19:dd:d9:dd:c25:c25:94de:46fb
2532c19:dd:d9:dd:c25:c25:94de:46fc/1282c19:dd:d9:dd:c25:c25:94de:46fc
2542c19:dd:d9:dd:c25:c25:94de:46fd/1282c19:dd:d9:dd:c25:c25:94de:46fd
2552c19:dd:d9:dd:c25:c25:94de:46fe/1282c19:dd:d9:dd:c25:c25:94de:46fe
2562c19:dd:d9:dd:c25:c25:94de:46ff/1282c19:dd:d9:dd:c25:c25:94de:46ff

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.