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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:4800/120
First address
2c19:dd:d9:dd:c25:c25:94de:4800
Last address
2c19:dd:d9:dd:c25:c25:94de:48ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:4800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.4.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:4800/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:4800/1282c19:dd:d9:dd:c25:c25:94de:4800
22c19:dd:d9:dd:c25:c25:94de:4801/1282c19:dd:d9:dd:c25:c25:94de:4801
32c19:dd:d9:dd:c25:c25:94de:4802/1282c19:dd:d9:dd:c25:c25:94de:4802
42c19:dd:d9:dd:c25:c25:94de:4803/1282c19:dd:d9:dd:c25:c25:94de:4803
52c19:dd:d9:dd:c25:c25:94de:4804/1282c19:dd:d9:dd:c25:c25:94de:4804
62c19:dd:d9:dd:c25:c25:94de:4805/1282c19:dd:d9:dd:c25:c25:94de:4805
72c19:dd:d9:dd:c25:c25:94de:4806/1282c19:dd:d9:dd:c25:c25:94de:4806
82c19:dd:d9:dd:c25:c25:94de:4807/1282c19:dd:d9:dd:c25:c25:94de:4807
92c19:dd:d9:dd:c25:c25:94de:4808/1282c19:dd:d9:dd:c25:c25:94de:4808
102c19:dd:d9:dd:c25:c25:94de:4809/1282c19:dd:d9:dd:c25:c25:94de:4809
112c19:dd:d9:dd:c25:c25:94de:480a/1282c19:dd:d9:dd:c25:c25:94de:480a
122c19:dd:d9:dd:c25:c25:94de:480b/1282c19:dd:d9:dd:c25:c25:94de:480b
132c19:dd:d9:dd:c25:c25:94de:480c/1282c19:dd:d9:dd:c25:c25:94de:480c
142c19:dd:d9:dd:c25:c25:94de:480d/1282c19:dd:d9:dd:c25:c25:94de:480d
152c19:dd:d9:dd:c25:c25:94de:480e/1282c19:dd:d9:dd:c25:c25:94de:480e
162c19:dd:d9:dd:c25:c25:94de:480f/1282c19:dd:d9:dd:c25:c25:94de:480f
172c19:dd:d9:dd:c25:c25:94de:4810/1282c19:dd:d9:dd:c25:c25:94de:4810
182c19:dd:d9:dd:c25:c25:94de:4811/1282c19:dd:d9:dd:c25:c25:94de:4811
192c19:dd:d9:dd:c25:c25:94de:4812/1282c19:dd:d9:dd:c25:c25:94de:4812
202c19:dd:d9:dd:c25:c25:94de:4813/1282c19:dd:d9:dd:c25:c25:94de:4813
212c19:dd:d9:dd:c25:c25:94de:4814/1282c19:dd:d9:dd:c25:c25:94de:4814
222c19:dd:d9:dd:c25:c25:94de:4815/1282c19:dd:d9:dd:c25:c25:94de:4815
232c19:dd:d9:dd:c25:c25:94de:4816/1282c19:dd:d9:dd:c25:c25:94de:4816
242c19:dd:d9:dd:c25:c25:94de:4817/1282c19:dd:d9:dd:c25:c25:94de:4817
252c19:dd:d9:dd:c25:c25:94de:4818/1282c19:dd:d9:dd:c25:c25:94de:4818
262c19:dd:d9:dd:c25:c25:94de:4819/1282c19:dd:d9:dd:c25:c25:94de:4819
272c19:dd:d9:dd:c25:c25:94de:481a/1282c19:dd:d9:dd:c25:c25:94de:481a
282c19:dd:d9:dd:c25:c25:94de:481b/1282c19:dd:d9:dd:c25:c25:94de:481b
292c19:dd:d9:dd:c25:c25:94de:481c/1282c19:dd:d9:dd:c25:c25:94de:481c
302c19:dd:d9:dd:c25:c25:94de:481d/1282c19:dd:d9:dd:c25:c25:94de:481d
312c19:dd:d9:dd:c25:c25:94de:481e/1282c19:dd:d9:dd:c25:c25:94de:481e
322c19:dd:d9:dd:c25:c25:94de:481f/1282c19:dd:d9:dd:c25:c25:94de:481f
332c19:dd:d9:dd:c25:c25:94de:4820/1282c19:dd:d9:dd:c25:c25:94de:4820
342c19:dd:d9:dd:c25:c25:94de:4821/1282c19:dd:d9:dd:c25:c25:94de:4821
352c19:dd:d9:dd:c25:c25:94de:4822/1282c19:dd:d9:dd:c25:c25:94de:4822
362c19:dd:d9:dd:c25:c25:94de:4823/1282c19:dd:d9:dd:c25:c25:94de:4823
372c19:dd:d9:dd:c25:c25:94de:4824/1282c19:dd:d9:dd:c25:c25:94de:4824
382c19:dd:d9:dd:c25:c25:94de:4825/1282c19:dd:d9:dd:c25:c25:94de:4825
392c19:dd:d9:dd:c25:c25:94de:4826/1282c19:dd:d9:dd:c25:c25:94de:4826
402c19:dd:d9:dd:c25:c25:94de:4827/1282c19:dd:d9:dd:c25:c25:94de:4827
412c19:dd:d9:dd:c25:c25:94de:4828/1282c19:dd:d9:dd:c25:c25:94de:4828
422c19:dd:d9:dd:c25:c25:94de:4829/1282c19:dd:d9:dd:c25:c25:94de:4829
432c19:dd:d9:dd:c25:c25:94de:482a/1282c19:dd:d9:dd:c25:c25:94de:482a
442c19:dd:d9:dd:c25:c25:94de:482b/1282c19:dd:d9:dd:c25:c25:94de:482b
452c19:dd:d9:dd:c25:c25:94de:482c/1282c19:dd:d9:dd:c25:c25:94de:482c
462c19:dd:d9:dd:c25:c25:94de:482d/1282c19:dd:d9:dd:c25:c25:94de:482d
472c19:dd:d9:dd:c25:c25:94de:482e/1282c19:dd:d9:dd:c25:c25:94de:482e
482c19:dd:d9:dd:c25:c25:94de:482f/1282c19:dd:d9:dd:c25:c25:94de:482f
492c19:dd:d9:dd:c25:c25:94de:4830/1282c19:dd:d9:dd:c25:c25:94de:4830
502c19:dd:d9:dd:c25:c25:94de:4831/1282c19:dd:d9:dd:c25:c25:94de:4831
512c19:dd:d9:dd:c25:c25:94de:4832/1282c19:dd:d9:dd:c25:c25:94de:4832
522c19:dd:d9:dd:c25:c25:94de:4833/1282c19:dd:d9:dd:c25:c25:94de:4833
532c19:dd:d9:dd:c25:c25:94de:4834/1282c19:dd:d9:dd:c25:c25:94de:4834
542c19:dd:d9:dd:c25:c25:94de:4835/1282c19:dd:d9:dd:c25:c25:94de:4835
552c19:dd:d9:dd:c25:c25:94de:4836/1282c19:dd:d9:dd:c25:c25:94de:4836
562c19:dd:d9:dd:c25:c25:94de:4837/1282c19:dd:d9:dd:c25:c25:94de:4837
572c19:dd:d9:dd:c25:c25:94de:4838/1282c19:dd:d9:dd:c25:c25:94de:4838
582c19:dd:d9:dd:c25:c25:94de:4839/1282c19:dd:d9:dd:c25:c25:94de:4839
592c19:dd:d9:dd:c25:c25:94de:483a/1282c19:dd:d9:dd:c25:c25:94de:483a
602c19:dd:d9:dd:c25:c25:94de:483b/1282c19:dd:d9:dd:c25:c25:94de:483b
612c19:dd:d9:dd:c25:c25:94de:483c/1282c19:dd:d9:dd:c25:c25:94de:483c
622c19:dd:d9:dd:c25:c25:94de:483d/1282c19:dd:d9:dd:c25:c25:94de:483d
632c19:dd:d9:dd:c25:c25:94de:483e/1282c19:dd:d9:dd:c25:c25:94de:483e
642c19:dd:d9:dd:c25:c25:94de:483f/1282c19:dd:d9:dd:c25:c25:94de:483f
652c19:dd:d9:dd:c25:c25:94de:4840/1282c19:dd:d9:dd:c25:c25:94de:4840
662c19:dd:d9:dd:c25:c25:94de:4841/1282c19:dd:d9:dd:c25:c25:94de:4841
672c19:dd:d9:dd:c25:c25:94de:4842/1282c19:dd:d9:dd:c25:c25:94de:4842
682c19:dd:d9:dd:c25:c25:94de:4843/1282c19:dd:d9:dd:c25:c25:94de:4843
692c19:dd:d9:dd:c25:c25:94de:4844/1282c19:dd:d9:dd:c25:c25:94de:4844
702c19:dd:d9:dd:c25:c25:94de:4845/1282c19:dd:d9:dd:c25:c25:94de:4845
712c19:dd:d9:dd:c25:c25:94de:4846/1282c19:dd:d9:dd:c25:c25:94de:4846
722c19:dd:d9:dd:c25:c25:94de:4847/1282c19:dd:d9:dd:c25:c25:94de:4847
732c19:dd:d9:dd:c25:c25:94de:4848/1282c19:dd:d9:dd:c25:c25:94de:4848
742c19:dd:d9:dd:c25:c25:94de:4849/1282c19:dd:d9:dd:c25:c25:94de:4849
752c19:dd:d9:dd:c25:c25:94de:484a/1282c19:dd:d9:dd:c25:c25:94de:484a
762c19:dd:d9:dd:c25:c25:94de:484b/1282c19:dd:d9:dd:c25:c25:94de:484b
772c19:dd:d9:dd:c25:c25:94de:484c/1282c19:dd:d9:dd:c25:c25:94de:484c
782c19:dd:d9:dd:c25:c25:94de:484d/1282c19:dd:d9:dd:c25:c25:94de:484d
792c19:dd:d9:dd:c25:c25:94de:484e/1282c19:dd:d9:dd:c25:c25:94de:484e
802c19:dd:d9:dd:c25:c25:94de:484f/1282c19:dd:d9:dd:c25:c25:94de:484f
812c19:dd:d9:dd:c25:c25:94de:4850/1282c19:dd:d9:dd:c25:c25:94de:4850
822c19:dd:d9:dd:c25:c25:94de:4851/1282c19:dd:d9:dd:c25:c25:94de:4851
832c19:dd:d9:dd:c25:c25:94de:4852/1282c19:dd:d9:dd:c25:c25:94de:4852
842c19:dd:d9:dd:c25:c25:94de:4853/1282c19:dd:d9:dd:c25:c25:94de:4853
852c19:dd:d9:dd:c25:c25:94de:4854/1282c19:dd:d9:dd:c25:c25:94de:4854
862c19:dd:d9:dd:c25:c25:94de:4855/1282c19:dd:d9:dd:c25:c25:94de:4855
872c19:dd:d9:dd:c25:c25:94de:4856/1282c19:dd:d9:dd:c25:c25:94de:4856
882c19:dd:d9:dd:c25:c25:94de:4857/1282c19:dd:d9:dd:c25:c25:94de:4857
892c19:dd:d9:dd:c25:c25:94de:4858/1282c19:dd:d9:dd:c25:c25:94de:4858
902c19:dd:d9:dd:c25:c25:94de:4859/1282c19:dd:d9:dd:c25:c25:94de:4859
912c19:dd:d9:dd:c25:c25:94de:485a/1282c19:dd:d9:dd:c25:c25:94de:485a
922c19:dd:d9:dd:c25:c25:94de:485b/1282c19:dd:d9:dd:c25:c25:94de:485b
932c19:dd:d9:dd:c25:c25:94de:485c/1282c19:dd:d9:dd:c25:c25:94de:485c
942c19:dd:d9:dd:c25:c25:94de:485d/1282c19:dd:d9:dd:c25:c25:94de:485d
952c19:dd:d9:dd:c25:c25:94de:485e/1282c19:dd:d9:dd:c25:c25:94de:485e
962c19:dd:d9:dd:c25:c25:94de:485f/1282c19:dd:d9:dd:c25:c25:94de:485f
972c19:dd:d9:dd:c25:c25:94de:4860/1282c19:dd:d9:dd:c25:c25:94de:4860
982c19:dd:d9:dd:c25:c25:94de:4861/1282c19:dd:d9:dd:c25:c25:94de:4861
992c19:dd:d9:dd:c25:c25:94de:4862/1282c19:dd:d9:dd:c25:c25:94de:4862
1002c19:dd:d9:dd:c25:c25:94de:4863/1282c19:dd:d9:dd:c25:c25:94de:4863
1012c19:dd:d9:dd:c25:c25:94de:4864/1282c19:dd:d9:dd:c25:c25:94de:4864
1022c19:dd:d9:dd:c25:c25:94de:4865/1282c19:dd:d9:dd:c25:c25:94de:4865
1032c19:dd:d9:dd:c25:c25:94de:4866/1282c19:dd:d9:dd:c25:c25:94de:4866
1042c19:dd:d9:dd:c25:c25:94de:4867/1282c19:dd:d9:dd:c25:c25:94de:4867
1052c19:dd:d9:dd:c25:c25:94de:4868/1282c19:dd:d9:dd:c25:c25:94de:4868
1062c19:dd:d9:dd:c25:c25:94de:4869/1282c19:dd:d9:dd:c25:c25:94de:4869
1072c19:dd:d9:dd:c25:c25:94de:486a/1282c19:dd:d9:dd:c25:c25:94de:486a
1082c19:dd:d9:dd:c25:c25:94de:486b/1282c19:dd:d9:dd:c25:c25:94de:486b
1092c19:dd:d9:dd:c25:c25:94de:486c/1282c19:dd:d9:dd:c25:c25:94de:486c
1102c19:dd:d9:dd:c25:c25:94de:486d/1282c19:dd:d9:dd:c25:c25:94de:486d
1112c19:dd:d9:dd:c25:c25:94de:486e/1282c19:dd:d9:dd:c25:c25:94de:486e
1122c19:dd:d9:dd:c25:c25:94de:486f/1282c19:dd:d9:dd:c25:c25:94de:486f
1132c19:dd:d9:dd:c25:c25:94de:4870/1282c19:dd:d9:dd:c25:c25:94de:4870
1142c19:dd:d9:dd:c25:c25:94de:4871/1282c19:dd:d9:dd:c25:c25:94de:4871
1152c19:dd:d9:dd:c25:c25:94de:4872/1282c19:dd:d9:dd:c25:c25:94de:4872
1162c19:dd:d9:dd:c25:c25:94de:4873/1282c19:dd:d9:dd:c25:c25:94de:4873
1172c19:dd:d9:dd:c25:c25:94de:4874/1282c19:dd:d9:dd:c25:c25:94de:4874
1182c19:dd:d9:dd:c25:c25:94de:4875/1282c19:dd:d9:dd:c25:c25:94de:4875
1192c19:dd:d9:dd:c25:c25:94de:4876/1282c19:dd:d9:dd:c25:c25:94de:4876
1202c19:dd:d9:dd:c25:c25:94de:4877/1282c19:dd:d9:dd:c25:c25:94de:4877
1212c19:dd:d9:dd:c25:c25:94de:4878/1282c19:dd:d9:dd:c25:c25:94de:4878
1222c19:dd:d9:dd:c25:c25:94de:4879/1282c19:dd:d9:dd:c25:c25:94de:4879
1232c19:dd:d9:dd:c25:c25:94de:487a/1282c19:dd:d9:dd:c25:c25:94de:487a
1242c19:dd:d9:dd:c25:c25:94de:487b/1282c19:dd:d9:dd:c25:c25:94de:487b
1252c19:dd:d9:dd:c25:c25:94de:487c/1282c19:dd:d9:dd:c25:c25:94de:487c
1262c19:dd:d9:dd:c25:c25:94de:487d/1282c19:dd:d9:dd:c25:c25:94de:487d
1272c19:dd:d9:dd:c25:c25:94de:487e/1282c19:dd:d9:dd:c25:c25:94de:487e
1282c19:dd:d9:dd:c25:c25:94de:487f/1282c19:dd:d9:dd:c25:c25:94de:487f
1292c19:dd:d9:dd:c25:c25:94de:4880/1282c19:dd:d9:dd:c25:c25:94de:4880
1302c19:dd:d9:dd:c25:c25:94de:4881/1282c19:dd:d9:dd:c25:c25:94de:4881
1312c19:dd:d9:dd:c25:c25:94de:4882/1282c19:dd:d9:dd:c25:c25:94de:4882
1322c19:dd:d9:dd:c25:c25:94de:4883/1282c19:dd:d9:dd:c25:c25:94de:4883
1332c19:dd:d9:dd:c25:c25:94de:4884/1282c19:dd:d9:dd:c25:c25:94de:4884
1342c19:dd:d9:dd:c25:c25:94de:4885/1282c19:dd:d9:dd:c25:c25:94de:4885
1352c19:dd:d9:dd:c25:c25:94de:4886/1282c19:dd:d9:dd:c25:c25:94de:4886
1362c19:dd:d9:dd:c25:c25:94de:4887/1282c19:dd:d9:dd:c25:c25:94de:4887
1372c19:dd:d9:dd:c25:c25:94de:4888/1282c19:dd:d9:dd:c25:c25:94de:4888
1382c19:dd:d9:dd:c25:c25:94de:4889/1282c19:dd:d9:dd:c25:c25:94de:4889
1392c19:dd:d9:dd:c25:c25:94de:488a/1282c19:dd:d9:dd:c25:c25:94de:488a
1402c19:dd:d9:dd:c25:c25:94de:488b/1282c19:dd:d9:dd:c25:c25:94de:488b
1412c19:dd:d9:dd:c25:c25:94de:488c/1282c19:dd:d9:dd:c25:c25:94de:488c
1422c19:dd:d9:dd:c25:c25:94de:488d/1282c19:dd:d9:dd:c25:c25:94de:488d
1432c19:dd:d9:dd:c25:c25:94de:488e/1282c19:dd:d9:dd:c25:c25:94de:488e
1442c19:dd:d9:dd:c25:c25:94de:488f/1282c19:dd:d9:dd:c25:c25:94de:488f
1452c19:dd:d9:dd:c25:c25:94de:4890/1282c19:dd:d9:dd:c25:c25:94de:4890
1462c19:dd:d9:dd:c25:c25:94de:4891/1282c19:dd:d9:dd:c25:c25:94de:4891
1472c19:dd:d9:dd:c25:c25:94de:4892/1282c19:dd:d9:dd:c25:c25:94de:4892
1482c19:dd:d9:dd:c25:c25:94de:4893/1282c19:dd:d9:dd:c25:c25:94de:4893
1492c19:dd:d9:dd:c25:c25:94de:4894/1282c19:dd:d9:dd:c25:c25:94de:4894
1502c19:dd:d9:dd:c25:c25:94de:4895/1282c19:dd:d9:dd:c25:c25:94de:4895
1512c19:dd:d9:dd:c25:c25:94de:4896/1282c19:dd:d9:dd:c25:c25:94de:4896
1522c19:dd:d9:dd:c25:c25:94de:4897/1282c19:dd:d9:dd:c25:c25:94de:4897
1532c19:dd:d9:dd:c25:c25:94de:4898/1282c19:dd:d9:dd:c25:c25:94de:4898
1542c19:dd:d9:dd:c25:c25:94de:4899/1282c19:dd:d9:dd:c25:c25:94de:4899
1552c19:dd:d9:dd:c25:c25:94de:489a/1282c19:dd:d9:dd:c25:c25:94de:489a
1562c19:dd:d9:dd:c25:c25:94de:489b/1282c19:dd:d9:dd:c25:c25:94de:489b
1572c19:dd:d9:dd:c25:c25:94de:489c/1282c19:dd:d9:dd:c25:c25:94de:489c
1582c19:dd:d9:dd:c25:c25:94de:489d/1282c19:dd:d9:dd:c25:c25:94de:489d
1592c19:dd:d9:dd:c25:c25:94de:489e/1282c19:dd:d9:dd:c25:c25:94de:489e
1602c19:dd:d9:dd:c25:c25:94de:489f/1282c19:dd:d9:dd:c25:c25:94de:489f
1612c19:dd:d9:dd:c25:c25:94de:48a0/1282c19:dd:d9:dd:c25:c25:94de:48a0
1622c19:dd:d9:dd:c25:c25:94de:48a1/1282c19:dd:d9:dd:c25:c25:94de:48a1
1632c19:dd:d9:dd:c25:c25:94de:48a2/1282c19:dd:d9:dd:c25:c25:94de:48a2
1642c19:dd:d9:dd:c25:c25:94de:48a3/1282c19:dd:d9:dd:c25:c25:94de:48a3
1652c19:dd:d9:dd:c25:c25:94de:48a4/1282c19:dd:d9:dd:c25:c25:94de:48a4
1662c19:dd:d9:dd:c25:c25:94de:48a5/1282c19:dd:d9:dd:c25:c25:94de:48a5
1672c19:dd:d9:dd:c25:c25:94de:48a6/1282c19:dd:d9:dd:c25:c25:94de:48a6
1682c19:dd:d9:dd:c25:c25:94de:48a7/1282c19:dd:d9:dd:c25:c25:94de:48a7
1692c19:dd:d9:dd:c25:c25:94de:48a8/1282c19:dd:d9:dd:c25:c25:94de:48a8
1702c19:dd:d9:dd:c25:c25:94de:48a9/1282c19:dd:d9:dd:c25:c25:94de:48a9
1712c19:dd:d9:dd:c25:c25:94de:48aa/1282c19:dd:d9:dd:c25:c25:94de:48aa
1722c19:dd:d9:dd:c25:c25:94de:48ab/1282c19:dd:d9:dd:c25:c25:94de:48ab
1732c19:dd:d9:dd:c25:c25:94de:48ac/1282c19:dd:d9:dd:c25:c25:94de:48ac
1742c19:dd:d9:dd:c25:c25:94de:48ad/1282c19:dd:d9:dd:c25:c25:94de:48ad
1752c19:dd:d9:dd:c25:c25:94de:48ae/1282c19:dd:d9:dd:c25:c25:94de:48ae
1762c19:dd:d9:dd:c25:c25:94de:48af/1282c19:dd:d9:dd:c25:c25:94de:48af
1772c19:dd:d9:dd:c25:c25:94de:48b0/1282c19:dd:d9:dd:c25:c25:94de:48b0
1782c19:dd:d9:dd:c25:c25:94de:48b1/1282c19:dd:d9:dd:c25:c25:94de:48b1
1792c19:dd:d9:dd:c25:c25:94de:48b2/1282c19:dd:d9:dd:c25:c25:94de:48b2
1802c19:dd:d9:dd:c25:c25:94de:48b3/1282c19:dd:d9:dd:c25:c25:94de:48b3
1812c19:dd:d9:dd:c25:c25:94de:48b4/1282c19:dd:d9:dd:c25:c25:94de:48b4
1822c19:dd:d9:dd:c25:c25:94de:48b5/1282c19:dd:d9:dd:c25:c25:94de:48b5
1832c19:dd:d9:dd:c25:c25:94de:48b6/1282c19:dd:d9:dd:c25:c25:94de:48b6
1842c19:dd:d9:dd:c25:c25:94de:48b7/1282c19:dd:d9:dd:c25:c25:94de:48b7
1852c19:dd:d9:dd:c25:c25:94de:48b8/1282c19:dd:d9:dd:c25:c25:94de:48b8
1862c19:dd:d9:dd:c25:c25:94de:48b9/1282c19:dd:d9:dd:c25:c25:94de:48b9
1872c19:dd:d9:dd:c25:c25:94de:48ba/1282c19:dd:d9:dd:c25:c25:94de:48ba
1882c19:dd:d9:dd:c25:c25:94de:48bb/1282c19:dd:d9:dd:c25:c25:94de:48bb
1892c19:dd:d9:dd:c25:c25:94de:48bc/1282c19:dd:d9:dd:c25:c25:94de:48bc
1902c19:dd:d9:dd:c25:c25:94de:48bd/1282c19:dd:d9:dd:c25:c25:94de:48bd
1912c19:dd:d9:dd:c25:c25:94de:48be/1282c19:dd:d9:dd:c25:c25:94de:48be
1922c19:dd:d9:dd:c25:c25:94de:48bf/1282c19:dd:d9:dd:c25:c25:94de:48bf
1932c19:dd:d9:dd:c25:c25:94de:48c0/1282c19:dd:d9:dd:c25:c25:94de:48c0
1942c19:dd:d9:dd:c25:c25:94de:48c1/1282c19:dd:d9:dd:c25:c25:94de:48c1
1952c19:dd:d9:dd:c25:c25:94de:48c2/1282c19:dd:d9:dd:c25:c25:94de:48c2
1962c19:dd:d9:dd:c25:c25:94de:48c3/1282c19:dd:d9:dd:c25:c25:94de:48c3
1972c19:dd:d9:dd:c25:c25:94de:48c4/1282c19:dd:d9:dd:c25:c25:94de:48c4
1982c19:dd:d9:dd:c25:c25:94de:48c5/1282c19:dd:d9:dd:c25:c25:94de:48c5
1992c19:dd:d9:dd:c25:c25:94de:48c6/1282c19:dd:d9:dd:c25:c25:94de:48c6
2002c19:dd:d9:dd:c25:c25:94de:48c7/1282c19:dd:d9:dd:c25:c25:94de:48c7
2012c19:dd:d9:dd:c25:c25:94de:48c8/1282c19:dd:d9:dd:c25:c25:94de:48c8
2022c19:dd:d9:dd:c25:c25:94de:48c9/1282c19:dd:d9:dd:c25:c25:94de:48c9
2032c19:dd:d9:dd:c25:c25:94de:48ca/1282c19:dd:d9:dd:c25:c25:94de:48ca
2042c19:dd:d9:dd:c25:c25:94de:48cb/1282c19:dd:d9:dd:c25:c25:94de:48cb
2052c19:dd:d9:dd:c25:c25:94de:48cc/1282c19:dd:d9:dd:c25:c25:94de:48cc
2062c19:dd:d9:dd:c25:c25:94de:48cd/1282c19:dd:d9:dd:c25:c25:94de:48cd
2072c19:dd:d9:dd:c25:c25:94de:48ce/1282c19:dd:d9:dd:c25:c25:94de:48ce
2082c19:dd:d9:dd:c25:c25:94de:48cf/1282c19:dd:d9:dd:c25:c25:94de:48cf
2092c19:dd:d9:dd:c25:c25:94de:48d0/1282c19:dd:d9:dd:c25:c25:94de:48d0
2102c19:dd:d9:dd:c25:c25:94de:48d1/1282c19:dd:d9:dd:c25:c25:94de:48d1
2112c19:dd:d9:dd:c25:c25:94de:48d2/1282c19:dd:d9:dd:c25:c25:94de:48d2
2122c19:dd:d9:dd:c25:c25:94de:48d3/1282c19:dd:d9:dd:c25:c25:94de:48d3
2132c19:dd:d9:dd:c25:c25:94de:48d4/1282c19:dd:d9:dd:c25:c25:94de:48d4
2142c19:dd:d9:dd:c25:c25:94de:48d5/1282c19:dd:d9:dd:c25:c25:94de:48d5
2152c19:dd:d9:dd:c25:c25:94de:48d6/1282c19:dd:d9:dd:c25:c25:94de:48d6
2162c19:dd:d9:dd:c25:c25:94de:48d7/1282c19:dd:d9:dd:c25:c25:94de:48d7
2172c19:dd:d9:dd:c25:c25:94de:48d8/1282c19:dd:d9:dd:c25:c25:94de:48d8
2182c19:dd:d9:dd:c25:c25:94de:48d9/1282c19:dd:d9:dd:c25:c25:94de:48d9
2192c19:dd:d9:dd:c25:c25:94de:48da/1282c19:dd:d9:dd:c25:c25:94de:48da
2202c19:dd:d9:dd:c25:c25:94de:48db/1282c19:dd:d9:dd:c25:c25:94de:48db
2212c19:dd:d9:dd:c25:c25:94de:48dc/1282c19:dd:d9:dd:c25:c25:94de:48dc
2222c19:dd:d9:dd:c25:c25:94de:48dd/1282c19:dd:d9:dd:c25:c25:94de:48dd
2232c19:dd:d9:dd:c25:c25:94de:48de/1282c19:dd:d9:dd:c25:c25:94de:48de
2242c19:dd:d9:dd:c25:c25:94de:48df/1282c19:dd:d9:dd:c25:c25:94de:48df
2252c19:dd:d9:dd:c25:c25:94de:48e0/1282c19:dd:d9:dd:c25:c25:94de:48e0
2262c19:dd:d9:dd:c25:c25:94de:48e1/1282c19:dd:d9:dd:c25:c25:94de:48e1
2272c19:dd:d9:dd:c25:c25:94de:48e2/1282c19:dd:d9:dd:c25:c25:94de:48e2
2282c19:dd:d9:dd:c25:c25:94de:48e3/1282c19:dd:d9:dd:c25:c25:94de:48e3
2292c19:dd:d9:dd:c25:c25:94de:48e4/1282c19:dd:d9:dd:c25:c25:94de:48e4
2302c19:dd:d9:dd:c25:c25:94de:48e5/1282c19:dd:d9:dd:c25:c25:94de:48e5
2312c19:dd:d9:dd:c25:c25:94de:48e6/1282c19:dd:d9:dd:c25:c25:94de:48e6
2322c19:dd:d9:dd:c25:c25:94de:48e7/1282c19:dd:d9:dd:c25:c25:94de:48e7
2332c19:dd:d9:dd:c25:c25:94de:48e8/1282c19:dd:d9:dd:c25:c25:94de:48e8
2342c19:dd:d9:dd:c25:c25:94de:48e9/1282c19:dd:d9:dd:c25:c25:94de:48e9
2352c19:dd:d9:dd:c25:c25:94de:48ea/1282c19:dd:d9:dd:c25:c25:94de:48ea
2362c19:dd:d9:dd:c25:c25:94de:48eb/1282c19:dd:d9:dd:c25:c25:94de:48eb
2372c19:dd:d9:dd:c25:c25:94de:48ec/1282c19:dd:d9:dd:c25:c25:94de:48ec
2382c19:dd:d9:dd:c25:c25:94de:48ed/1282c19:dd:d9:dd:c25:c25:94de:48ed
2392c19:dd:d9:dd:c25:c25:94de:48ee/1282c19:dd:d9:dd:c25:c25:94de:48ee
2402c19:dd:d9:dd:c25:c25:94de:48ef/1282c19:dd:d9:dd:c25:c25:94de:48ef
2412c19:dd:d9:dd:c25:c25:94de:48f0/1282c19:dd:d9:dd:c25:c25:94de:48f0
2422c19:dd:d9:dd:c25:c25:94de:48f1/1282c19:dd:d9:dd:c25:c25:94de:48f1
2432c19:dd:d9:dd:c25:c25:94de:48f2/1282c19:dd:d9:dd:c25:c25:94de:48f2
2442c19:dd:d9:dd:c25:c25:94de:48f3/1282c19:dd:d9:dd:c25:c25:94de:48f3
2452c19:dd:d9:dd:c25:c25:94de:48f4/1282c19:dd:d9:dd:c25:c25:94de:48f4
2462c19:dd:d9:dd:c25:c25:94de:48f5/1282c19:dd:d9:dd:c25:c25:94de:48f5
2472c19:dd:d9:dd:c25:c25:94de:48f6/1282c19:dd:d9:dd:c25:c25:94de:48f6
2482c19:dd:d9:dd:c25:c25:94de:48f7/1282c19:dd:d9:dd:c25:c25:94de:48f7
2492c19:dd:d9:dd:c25:c25:94de:48f8/1282c19:dd:d9:dd:c25:c25:94de:48f8
2502c19:dd:d9:dd:c25:c25:94de:48f9/1282c19:dd:d9:dd:c25:c25:94de:48f9
2512c19:dd:d9:dd:c25:c25:94de:48fa/1282c19:dd:d9:dd:c25:c25:94de:48fa
2522c19:dd:d9:dd:c25:c25:94de:48fb/1282c19:dd:d9:dd:c25:c25:94de:48fb
2532c19:dd:d9:dd:c25:c25:94de:48fc/1282c19:dd:d9:dd:c25:c25:94de:48fc
2542c19:dd:d9:dd:c25:c25:94de:48fd/1282c19:dd:d9:dd:c25:c25:94de:48fd
2552c19:dd:d9:dd:c25:c25:94de:48fe/1282c19:dd:d9:dd:c25:c25:94de:48fe
2562c19:dd:d9:dd:c25:c25:94de:48ff/1282c19:dd:d9:dd:c25:c25:94de:48ff

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.