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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:c418:e800/120
First address
2c19:dd:d9:dd:c25:c25:c418:e800
Last address
2c19:dd:d9:dd:c25:c25:c418:e8ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:c418:e800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.e.8.1.4.c.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:c418:e800/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:c418:e800/1282c19:dd:d9:dd:c25:c25:c418:e800
22c19:dd:d9:dd:c25:c25:c418:e801/1282c19:dd:d9:dd:c25:c25:c418:e801
32c19:dd:d9:dd:c25:c25:c418:e802/1282c19:dd:d9:dd:c25:c25:c418:e802
42c19:dd:d9:dd:c25:c25:c418:e803/1282c19:dd:d9:dd:c25:c25:c418:e803
52c19:dd:d9:dd:c25:c25:c418:e804/1282c19:dd:d9:dd:c25:c25:c418:e804
62c19:dd:d9:dd:c25:c25:c418:e805/1282c19:dd:d9:dd:c25:c25:c418:e805
72c19:dd:d9:dd:c25:c25:c418:e806/1282c19:dd:d9:dd:c25:c25:c418:e806
82c19:dd:d9:dd:c25:c25:c418:e807/1282c19:dd:d9:dd:c25:c25:c418:e807
92c19:dd:d9:dd:c25:c25:c418:e808/1282c19:dd:d9:dd:c25:c25:c418:e808
102c19:dd:d9:dd:c25:c25:c418:e809/1282c19:dd:d9:dd:c25:c25:c418:e809
112c19:dd:d9:dd:c25:c25:c418:e80a/1282c19:dd:d9:dd:c25:c25:c418:e80a
122c19:dd:d9:dd:c25:c25:c418:e80b/1282c19:dd:d9:dd:c25:c25:c418:e80b
132c19:dd:d9:dd:c25:c25:c418:e80c/1282c19:dd:d9:dd:c25:c25:c418:e80c
142c19:dd:d9:dd:c25:c25:c418:e80d/1282c19:dd:d9:dd:c25:c25:c418:e80d
152c19:dd:d9:dd:c25:c25:c418:e80e/1282c19:dd:d9:dd:c25:c25:c418:e80e
162c19:dd:d9:dd:c25:c25:c418:e80f/1282c19:dd:d9:dd:c25:c25:c418:e80f
172c19:dd:d9:dd:c25:c25:c418:e810/1282c19:dd:d9:dd:c25:c25:c418:e810
182c19:dd:d9:dd:c25:c25:c418:e811/1282c19:dd:d9:dd:c25:c25:c418:e811
192c19:dd:d9:dd:c25:c25:c418:e812/1282c19:dd:d9:dd:c25:c25:c418:e812
202c19:dd:d9:dd:c25:c25:c418:e813/1282c19:dd:d9:dd:c25:c25:c418:e813
212c19:dd:d9:dd:c25:c25:c418:e814/1282c19:dd:d9:dd:c25:c25:c418:e814
222c19:dd:d9:dd:c25:c25:c418:e815/1282c19:dd:d9:dd:c25:c25:c418:e815
232c19:dd:d9:dd:c25:c25:c418:e816/1282c19:dd:d9:dd:c25:c25:c418:e816
242c19:dd:d9:dd:c25:c25:c418:e817/1282c19:dd:d9:dd:c25:c25:c418:e817
252c19:dd:d9:dd:c25:c25:c418:e818/1282c19:dd:d9:dd:c25:c25:c418:e818
262c19:dd:d9:dd:c25:c25:c418:e819/1282c19:dd:d9:dd:c25:c25:c418:e819
272c19:dd:d9:dd:c25:c25:c418:e81a/1282c19:dd:d9:dd:c25:c25:c418:e81a
282c19:dd:d9:dd:c25:c25:c418:e81b/1282c19:dd:d9:dd:c25:c25:c418:e81b
292c19:dd:d9:dd:c25:c25:c418:e81c/1282c19:dd:d9:dd:c25:c25:c418:e81c
302c19:dd:d9:dd:c25:c25:c418:e81d/1282c19:dd:d9:dd:c25:c25:c418:e81d
312c19:dd:d9:dd:c25:c25:c418:e81e/1282c19:dd:d9:dd:c25:c25:c418:e81e
322c19:dd:d9:dd:c25:c25:c418:e81f/1282c19:dd:d9:dd:c25:c25:c418:e81f
332c19:dd:d9:dd:c25:c25:c418:e820/1282c19:dd:d9:dd:c25:c25:c418:e820
342c19:dd:d9:dd:c25:c25:c418:e821/1282c19:dd:d9:dd:c25:c25:c418:e821
352c19:dd:d9:dd:c25:c25:c418:e822/1282c19:dd:d9:dd:c25:c25:c418:e822
362c19:dd:d9:dd:c25:c25:c418:e823/1282c19:dd:d9:dd:c25:c25:c418:e823
372c19:dd:d9:dd:c25:c25:c418:e824/1282c19:dd:d9:dd:c25:c25:c418:e824
382c19:dd:d9:dd:c25:c25:c418:e825/1282c19:dd:d9:dd:c25:c25:c418:e825
392c19:dd:d9:dd:c25:c25:c418:e826/1282c19:dd:d9:dd:c25:c25:c418:e826
402c19:dd:d9:dd:c25:c25:c418:e827/1282c19:dd:d9:dd:c25:c25:c418:e827
412c19:dd:d9:dd:c25:c25:c418:e828/1282c19:dd:d9:dd:c25:c25:c418:e828
422c19:dd:d9:dd:c25:c25:c418:e829/1282c19:dd:d9:dd:c25:c25:c418:e829
432c19:dd:d9:dd:c25:c25:c418:e82a/1282c19:dd:d9:dd:c25:c25:c418:e82a
442c19:dd:d9:dd:c25:c25:c418:e82b/1282c19:dd:d9:dd:c25:c25:c418:e82b
452c19:dd:d9:dd:c25:c25:c418:e82c/1282c19:dd:d9:dd:c25:c25:c418:e82c
462c19:dd:d9:dd:c25:c25:c418:e82d/1282c19:dd:d9:dd:c25:c25:c418:e82d
472c19:dd:d9:dd:c25:c25:c418:e82e/1282c19:dd:d9:dd:c25:c25:c418:e82e
482c19:dd:d9:dd:c25:c25:c418:e82f/1282c19:dd:d9:dd:c25:c25:c418:e82f
492c19:dd:d9:dd:c25:c25:c418:e830/1282c19:dd:d9:dd:c25:c25:c418:e830
502c19:dd:d9:dd:c25:c25:c418:e831/1282c19:dd:d9:dd:c25:c25:c418:e831
512c19:dd:d9:dd:c25:c25:c418:e832/1282c19:dd:d9:dd:c25:c25:c418:e832
522c19:dd:d9:dd:c25:c25:c418:e833/1282c19:dd:d9:dd:c25:c25:c418:e833
532c19:dd:d9:dd:c25:c25:c418:e834/1282c19:dd:d9:dd:c25:c25:c418:e834
542c19:dd:d9:dd:c25:c25:c418:e835/1282c19:dd:d9:dd:c25:c25:c418:e835
552c19:dd:d9:dd:c25:c25:c418:e836/1282c19:dd:d9:dd:c25:c25:c418:e836
562c19:dd:d9:dd:c25:c25:c418:e837/1282c19:dd:d9:dd:c25:c25:c418:e837
572c19:dd:d9:dd:c25:c25:c418:e838/1282c19:dd:d9:dd:c25:c25:c418:e838
582c19:dd:d9:dd:c25:c25:c418:e839/1282c19:dd:d9:dd:c25:c25:c418:e839
592c19:dd:d9:dd:c25:c25:c418:e83a/1282c19:dd:d9:dd:c25:c25:c418:e83a
602c19:dd:d9:dd:c25:c25:c418:e83b/1282c19:dd:d9:dd:c25:c25:c418:e83b
612c19:dd:d9:dd:c25:c25:c418:e83c/1282c19:dd:d9:dd:c25:c25:c418:e83c
622c19:dd:d9:dd:c25:c25:c418:e83d/1282c19:dd:d9:dd:c25:c25:c418:e83d
632c19:dd:d9:dd:c25:c25:c418:e83e/1282c19:dd:d9:dd:c25:c25:c418:e83e
642c19:dd:d9:dd:c25:c25:c418:e83f/1282c19:dd:d9:dd:c25:c25:c418:e83f
652c19:dd:d9:dd:c25:c25:c418:e840/1282c19:dd:d9:dd:c25:c25:c418:e840
662c19:dd:d9:dd:c25:c25:c418:e841/1282c19:dd:d9:dd:c25:c25:c418:e841
672c19:dd:d9:dd:c25:c25:c418:e842/1282c19:dd:d9:dd:c25:c25:c418:e842
682c19:dd:d9:dd:c25:c25:c418:e843/1282c19:dd:d9:dd:c25:c25:c418:e843
692c19:dd:d9:dd:c25:c25:c418:e844/1282c19:dd:d9:dd:c25:c25:c418:e844
702c19:dd:d9:dd:c25:c25:c418:e845/1282c19:dd:d9:dd:c25:c25:c418:e845
712c19:dd:d9:dd:c25:c25:c418:e846/1282c19:dd:d9:dd:c25:c25:c418:e846
722c19:dd:d9:dd:c25:c25:c418:e847/1282c19:dd:d9:dd:c25:c25:c418:e847
732c19:dd:d9:dd:c25:c25:c418:e848/1282c19:dd:d9:dd:c25:c25:c418:e848
742c19:dd:d9:dd:c25:c25:c418:e849/1282c19:dd:d9:dd:c25:c25:c418:e849
752c19:dd:d9:dd:c25:c25:c418:e84a/1282c19:dd:d9:dd:c25:c25:c418:e84a
762c19:dd:d9:dd:c25:c25:c418:e84b/1282c19:dd:d9:dd:c25:c25:c418:e84b
772c19:dd:d9:dd:c25:c25:c418:e84c/1282c19:dd:d9:dd:c25:c25:c418:e84c
782c19:dd:d9:dd:c25:c25:c418:e84d/1282c19:dd:d9:dd:c25:c25:c418:e84d
792c19:dd:d9:dd:c25:c25:c418:e84e/1282c19:dd:d9:dd:c25:c25:c418:e84e
802c19:dd:d9:dd:c25:c25:c418:e84f/1282c19:dd:d9:dd:c25:c25:c418:e84f
812c19:dd:d9:dd:c25:c25:c418:e850/1282c19:dd:d9:dd:c25:c25:c418:e850
822c19:dd:d9:dd:c25:c25:c418:e851/1282c19:dd:d9:dd:c25:c25:c418:e851
832c19:dd:d9:dd:c25:c25:c418:e852/1282c19:dd:d9:dd:c25:c25:c418:e852
842c19:dd:d9:dd:c25:c25:c418:e853/1282c19:dd:d9:dd:c25:c25:c418:e853
852c19:dd:d9:dd:c25:c25:c418:e854/1282c19:dd:d9:dd:c25:c25:c418:e854
862c19:dd:d9:dd:c25:c25:c418:e855/1282c19:dd:d9:dd:c25:c25:c418:e855
872c19:dd:d9:dd:c25:c25:c418:e856/1282c19:dd:d9:dd:c25:c25:c418:e856
882c19:dd:d9:dd:c25:c25:c418:e857/1282c19:dd:d9:dd:c25:c25:c418:e857
892c19:dd:d9:dd:c25:c25:c418:e858/1282c19:dd:d9:dd:c25:c25:c418:e858
902c19:dd:d9:dd:c25:c25:c418:e859/1282c19:dd:d9:dd:c25:c25:c418:e859
912c19:dd:d9:dd:c25:c25:c418:e85a/1282c19:dd:d9:dd:c25:c25:c418:e85a
922c19:dd:d9:dd:c25:c25:c418:e85b/1282c19:dd:d9:dd:c25:c25:c418:e85b
932c19:dd:d9:dd:c25:c25:c418:e85c/1282c19:dd:d9:dd:c25:c25:c418:e85c
942c19:dd:d9:dd:c25:c25:c418:e85d/1282c19:dd:d9:dd:c25:c25:c418:e85d
952c19:dd:d9:dd:c25:c25:c418:e85e/1282c19:dd:d9:dd:c25:c25:c418:e85e
962c19:dd:d9:dd:c25:c25:c418:e85f/1282c19:dd:d9:dd:c25:c25:c418:e85f
972c19:dd:d9:dd:c25:c25:c418:e860/1282c19:dd:d9:dd:c25:c25:c418:e860
982c19:dd:d9:dd:c25:c25:c418:e861/1282c19:dd:d9:dd:c25:c25:c418:e861
992c19:dd:d9:dd:c25:c25:c418:e862/1282c19:dd:d9:dd:c25:c25:c418:e862
1002c19:dd:d9:dd:c25:c25:c418:e863/1282c19:dd:d9:dd:c25:c25:c418:e863
1012c19:dd:d9:dd:c25:c25:c418:e864/1282c19:dd:d9:dd:c25:c25:c418:e864
1022c19:dd:d9:dd:c25:c25:c418:e865/1282c19:dd:d9:dd:c25:c25:c418:e865
1032c19:dd:d9:dd:c25:c25:c418:e866/1282c19:dd:d9:dd:c25:c25:c418:e866
1042c19:dd:d9:dd:c25:c25:c418:e867/1282c19:dd:d9:dd:c25:c25:c418:e867
1052c19:dd:d9:dd:c25:c25:c418:e868/1282c19:dd:d9:dd:c25:c25:c418:e868
1062c19:dd:d9:dd:c25:c25:c418:e869/1282c19:dd:d9:dd:c25:c25:c418:e869
1072c19:dd:d9:dd:c25:c25:c418:e86a/1282c19:dd:d9:dd:c25:c25:c418:e86a
1082c19:dd:d9:dd:c25:c25:c418:e86b/1282c19:dd:d9:dd:c25:c25:c418:e86b
1092c19:dd:d9:dd:c25:c25:c418:e86c/1282c19:dd:d9:dd:c25:c25:c418:e86c
1102c19:dd:d9:dd:c25:c25:c418:e86d/1282c19:dd:d9:dd:c25:c25:c418:e86d
1112c19:dd:d9:dd:c25:c25:c418:e86e/1282c19:dd:d9:dd:c25:c25:c418:e86e
1122c19:dd:d9:dd:c25:c25:c418:e86f/1282c19:dd:d9:dd:c25:c25:c418:e86f
1132c19:dd:d9:dd:c25:c25:c418:e870/1282c19:dd:d9:dd:c25:c25:c418:e870
1142c19:dd:d9:dd:c25:c25:c418:e871/1282c19:dd:d9:dd:c25:c25:c418:e871
1152c19:dd:d9:dd:c25:c25:c418:e872/1282c19:dd:d9:dd:c25:c25:c418:e872
1162c19:dd:d9:dd:c25:c25:c418:e873/1282c19:dd:d9:dd:c25:c25:c418:e873
1172c19:dd:d9:dd:c25:c25:c418:e874/1282c19:dd:d9:dd:c25:c25:c418:e874
1182c19:dd:d9:dd:c25:c25:c418:e875/1282c19:dd:d9:dd:c25:c25:c418:e875
1192c19:dd:d9:dd:c25:c25:c418:e876/1282c19:dd:d9:dd:c25:c25:c418:e876
1202c19:dd:d9:dd:c25:c25:c418:e877/1282c19:dd:d9:dd:c25:c25:c418:e877
1212c19:dd:d9:dd:c25:c25:c418:e878/1282c19:dd:d9:dd:c25:c25:c418:e878
1222c19:dd:d9:dd:c25:c25:c418:e879/1282c19:dd:d9:dd:c25:c25:c418:e879
1232c19:dd:d9:dd:c25:c25:c418:e87a/1282c19:dd:d9:dd:c25:c25:c418:e87a
1242c19:dd:d9:dd:c25:c25:c418:e87b/1282c19:dd:d9:dd:c25:c25:c418:e87b
1252c19:dd:d9:dd:c25:c25:c418:e87c/1282c19:dd:d9:dd:c25:c25:c418:e87c
1262c19:dd:d9:dd:c25:c25:c418:e87d/1282c19:dd:d9:dd:c25:c25:c418:e87d
1272c19:dd:d9:dd:c25:c25:c418:e87e/1282c19:dd:d9:dd:c25:c25:c418:e87e
1282c19:dd:d9:dd:c25:c25:c418:e87f/1282c19:dd:d9:dd:c25:c25:c418:e87f
1292c19:dd:d9:dd:c25:c25:c418:e880/1282c19:dd:d9:dd:c25:c25:c418:e880
1302c19:dd:d9:dd:c25:c25:c418:e881/1282c19:dd:d9:dd:c25:c25:c418:e881
1312c19:dd:d9:dd:c25:c25:c418:e882/1282c19:dd:d9:dd:c25:c25:c418:e882
1322c19:dd:d9:dd:c25:c25:c418:e883/1282c19:dd:d9:dd:c25:c25:c418:e883
1332c19:dd:d9:dd:c25:c25:c418:e884/1282c19:dd:d9:dd:c25:c25:c418:e884
1342c19:dd:d9:dd:c25:c25:c418:e885/1282c19:dd:d9:dd:c25:c25:c418:e885
1352c19:dd:d9:dd:c25:c25:c418:e886/1282c19:dd:d9:dd:c25:c25:c418:e886
1362c19:dd:d9:dd:c25:c25:c418:e887/1282c19:dd:d9:dd:c25:c25:c418:e887
1372c19:dd:d9:dd:c25:c25:c418:e888/1282c19:dd:d9:dd:c25:c25:c418:e888
1382c19:dd:d9:dd:c25:c25:c418:e889/1282c19:dd:d9:dd:c25:c25:c418:e889
1392c19:dd:d9:dd:c25:c25:c418:e88a/1282c19:dd:d9:dd:c25:c25:c418:e88a
1402c19:dd:d9:dd:c25:c25:c418:e88b/1282c19:dd:d9:dd:c25:c25:c418:e88b
1412c19:dd:d9:dd:c25:c25:c418:e88c/1282c19:dd:d9:dd:c25:c25:c418:e88c
1422c19:dd:d9:dd:c25:c25:c418:e88d/1282c19:dd:d9:dd:c25:c25:c418:e88d
1432c19:dd:d9:dd:c25:c25:c418:e88e/1282c19:dd:d9:dd:c25:c25:c418:e88e
1442c19:dd:d9:dd:c25:c25:c418:e88f/1282c19:dd:d9:dd:c25:c25:c418:e88f
1452c19:dd:d9:dd:c25:c25:c418:e890/1282c19:dd:d9:dd:c25:c25:c418:e890
1462c19:dd:d9:dd:c25:c25:c418:e891/1282c19:dd:d9:dd:c25:c25:c418:e891
1472c19:dd:d9:dd:c25:c25:c418:e892/1282c19:dd:d9:dd:c25:c25:c418:e892
1482c19:dd:d9:dd:c25:c25:c418:e893/1282c19:dd:d9:dd:c25:c25:c418:e893
1492c19:dd:d9:dd:c25:c25:c418:e894/1282c19:dd:d9:dd:c25:c25:c418:e894
1502c19:dd:d9:dd:c25:c25:c418:e895/1282c19:dd:d9:dd:c25:c25:c418:e895
1512c19:dd:d9:dd:c25:c25:c418:e896/1282c19:dd:d9:dd:c25:c25:c418:e896
1522c19:dd:d9:dd:c25:c25:c418:e897/1282c19:dd:d9:dd:c25:c25:c418:e897
1532c19:dd:d9:dd:c25:c25:c418:e898/1282c19:dd:d9:dd:c25:c25:c418:e898
1542c19:dd:d9:dd:c25:c25:c418:e899/1282c19:dd:d9:dd:c25:c25:c418:e899
1552c19:dd:d9:dd:c25:c25:c418:e89a/1282c19:dd:d9:dd:c25:c25:c418:e89a
1562c19:dd:d9:dd:c25:c25:c418:e89b/1282c19:dd:d9:dd:c25:c25:c418:e89b
1572c19:dd:d9:dd:c25:c25:c418:e89c/1282c19:dd:d9:dd:c25:c25:c418:e89c
1582c19:dd:d9:dd:c25:c25:c418:e89d/1282c19:dd:d9:dd:c25:c25:c418:e89d
1592c19:dd:d9:dd:c25:c25:c418:e89e/1282c19:dd:d9:dd:c25:c25:c418:e89e
1602c19:dd:d9:dd:c25:c25:c418:e89f/1282c19:dd:d9:dd:c25:c25:c418:e89f
1612c19:dd:d9:dd:c25:c25:c418:e8a0/1282c19:dd:d9:dd:c25:c25:c418:e8a0
1622c19:dd:d9:dd:c25:c25:c418:e8a1/1282c19:dd:d9:dd:c25:c25:c418:e8a1
1632c19:dd:d9:dd:c25:c25:c418:e8a2/1282c19:dd:d9:dd:c25:c25:c418:e8a2
1642c19:dd:d9:dd:c25:c25:c418:e8a3/1282c19:dd:d9:dd:c25:c25:c418:e8a3
1652c19:dd:d9:dd:c25:c25:c418:e8a4/1282c19:dd:d9:dd:c25:c25:c418:e8a4
1662c19:dd:d9:dd:c25:c25:c418:e8a5/1282c19:dd:d9:dd:c25:c25:c418:e8a5
1672c19:dd:d9:dd:c25:c25:c418:e8a6/1282c19:dd:d9:dd:c25:c25:c418:e8a6
1682c19:dd:d9:dd:c25:c25:c418:e8a7/1282c19:dd:d9:dd:c25:c25:c418:e8a7
1692c19:dd:d9:dd:c25:c25:c418:e8a8/1282c19:dd:d9:dd:c25:c25:c418:e8a8
1702c19:dd:d9:dd:c25:c25:c418:e8a9/1282c19:dd:d9:dd:c25:c25:c418:e8a9
1712c19:dd:d9:dd:c25:c25:c418:e8aa/1282c19:dd:d9:dd:c25:c25:c418:e8aa
1722c19:dd:d9:dd:c25:c25:c418:e8ab/1282c19:dd:d9:dd:c25:c25:c418:e8ab
1732c19:dd:d9:dd:c25:c25:c418:e8ac/1282c19:dd:d9:dd:c25:c25:c418:e8ac
1742c19:dd:d9:dd:c25:c25:c418:e8ad/1282c19:dd:d9:dd:c25:c25:c418:e8ad
1752c19:dd:d9:dd:c25:c25:c418:e8ae/1282c19:dd:d9:dd:c25:c25:c418:e8ae
1762c19:dd:d9:dd:c25:c25:c418:e8af/1282c19:dd:d9:dd:c25:c25:c418:e8af
1772c19:dd:d9:dd:c25:c25:c418:e8b0/1282c19:dd:d9:dd:c25:c25:c418:e8b0
1782c19:dd:d9:dd:c25:c25:c418:e8b1/1282c19:dd:d9:dd:c25:c25:c418:e8b1
1792c19:dd:d9:dd:c25:c25:c418:e8b2/1282c19:dd:d9:dd:c25:c25:c418:e8b2
1802c19:dd:d9:dd:c25:c25:c418:e8b3/1282c19:dd:d9:dd:c25:c25:c418:e8b3
1812c19:dd:d9:dd:c25:c25:c418:e8b4/1282c19:dd:d9:dd:c25:c25:c418:e8b4
1822c19:dd:d9:dd:c25:c25:c418:e8b5/1282c19:dd:d9:dd:c25:c25:c418:e8b5
1832c19:dd:d9:dd:c25:c25:c418:e8b6/1282c19:dd:d9:dd:c25:c25:c418:e8b6
1842c19:dd:d9:dd:c25:c25:c418:e8b7/1282c19:dd:d9:dd:c25:c25:c418:e8b7
1852c19:dd:d9:dd:c25:c25:c418:e8b8/1282c19:dd:d9:dd:c25:c25:c418:e8b8
1862c19:dd:d9:dd:c25:c25:c418:e8b9/1282c19:dd:d9:dd:c25:c25:c418:e8b9
1872c19:dd:d9:dd:c25:c25:c418:e8ba/1282c19:dd:d9:dd:c25:c25:c418:e8ba
1882c19:dd:d9:dd:c25:c25:c418:e8bb/1282c19:dd:d9:dd:c25:c25:c418:e8bb
1892c19:dd:d9:dd:c25:c25:c418:e8bc/1282c19:dd:d9:dd:c25:c25:c418:e8bc
1902c19:dd:d9:dd:c25:c25:c418:e8bd/1282c19:dd:d9:dd:c25:c25:c418:e8bd
1912c19:dd:d9:dd:c25:c25:c418:e8be/1282c19:dd:d9:dd:c25:c25:c418:e8be
1922c19:dd:d9:dd:c25:c25:c418:e8bf/1282c19:dd:d9:dd:c25:c25:c418:e8bf
1932c19:dd:d9:dd:c25:c25:c418:e8c0/1282c19:dd:d9:dd:c25:c25:c418:e8c0
1942c19:dd:d9:dd:c25:c25:c418:e8c1/1282c19:dd:d9:dd:c25:c25:c418:e8c1
1952c19:dd:d9:dd:c25:c25:c418:e8c2/1282c19:dd:d9:dd:c25:c25:c418:e8c2
1962c19:dd:d9:dd:c25:c25:c418:e8c3/1282c19:dd:d9:dd:c25:c25:c418:e8c3
1972c19:dd:d9:dd:c25:c25:c418:e8c4/1282c19:dd:d9:dd:c25:c25:c418:e8c4
1982c19:dd:d9:dd:c25:c25:c418:e8c5/1282c19:dd:d9:dd:c25:c25:c418:e8c5
1992c19:dd:d9:dd:c25:c25:c418:e8c6/1282c19:dd:d9:dd:c25:c25:c418:e8c6
2002c19:dd:d9:dd:c25:c25:c418:e8c7/1282c19:dd:d9:dd:c25:c25:c418:e8c7
2012c19:dd:d9:dd:c25:c25:c418:e8c8/1282c19:dd:d9:dd:c25:c25:c418:e8c8
2022c19:dd:d9:dd:c25:c25:c418:e8c9/1282c19:dd:d9:dd:c25:c25:c418:e8c9
2032c19:dd:d9:dd:c25:c25:c418:e8ca/1282c19:dd:d9:dd:c25:c25:c418:e8ca
2042c19:dd:d9:dd:c25:c25:c418:e8cb/1282c19:dd:d9:dd:c25:c25:c418:e8cb
2052c19:dd:d9:dd:c25:c25:c418:e8cc/1282c19:dd:d9:dd:c25:c25:c418:e8cc
2062c19:dd:d9:dd:c25:c25:c418:e8cd/1282c19:dd:d9:dd:c25:c25:c418:e8cd
2072c19:dd:d9:dd:c25:c25:c418:e8ce/1282c19:dd:d9:dd:c25:c25:c418:e8ce
2082c19:dd:d9:dd:c25:c25:c418:e8cf/1282c19:dd:d9:dd:c25:c25:c418:e8cf
2092c19:dd:d9:dd:c25:c25:c418:e8d0/1282c19:dd:d9:dd:c25:c25:c418:e8d0
2102c19:dd:d9:dd:c25:c25:c418:e8d1/1282c19:dd:d9:dd:c25:c25:c418:e8d1
2112c19:dd:d9:dd:c25:c25:c418:e8d2/1282c19:dd:d9:dd:c25:c25:c418:e8d2
2122c19:dd:d9:dd:c25:c25:c418:e8d3/1282c19:dd:d9:dd:c25:c25:c418:e8d3
2132c19:dd:d9:dd:c25:c25:c418:e8d4/1282c19:dd:d9:dd:c25:c25:c418:e8d4
2142c19:dd:d9:dd:c25:c25:c418:e8d5/1282c19:dd:d9:dd:c25:c25:c418:e8d5
2152c19:dd:d9:dd:c25:c25:c418:e8d6/1282c19:dd:d9:dd:c25:c25:c418:e8d6
2162c19:dd:d9:dd:c25:c25:c418:e8d7/1282c19:dd:d9:dd:c25:c25:c418:e8d7
2172c19:dd:d9:dd:c25:c25:c418:e8d8/1282c19:dd:d9:dd:c25:c25:c418:e8d8
2182c19:dd:d9:dd:c25:c25:c418:e8d9/1282c19:dd:d9:dd:c25:c25:c418:e8d9
2192c19:dd:d9:dd:c25:c25:c418:e8da/1282c19:dd:d9:dd:c25:c25:c418:e8da
2202c19:dd:d9:dd:c25:c25:c418:e8db/1282c19:dd:d9:dd:c25:c25:c418:e8db
2212c19:dd:d9:dd:c25:c25:c418:e8dc/1282c19:dd:d9:dd:c25:c25:c418:e8dc
2222c19:dd:d9:dd:c25:c25:c418:e8dd/1282c19:dd:d9:dd:c25:c25:c418:e8dd
2232c19:dd:d9:dd:c25:c25:c418:e8de/1282c19:dd:d9:dd:c25:c25:c418:e8de
2242c19:dd:d9:dd:c25:c25:c418:e8df/1282c19:dd:d9:dd:c25:c25:c418:e8df
2252c19:dd:d9:dd:c25:c25:c418:e8e0/1282c19:dd:d9:dd:c25:c25:c418:e8e0
2262c19:dd:d9:dd:c25:c25:c418:e8e1/1282c19:dd:d9:dd:c25:c25:c418:e8e1
2272c19:dd:d9:dd:c25:c25:c418:e8e2/1282c19:dd:d9:dd:c25:c25:c418:e8e2
2282c19:dd:d9:dd:c25:c25:c418:e8e3/1282c19:dd:d9:dd:c25:c25:c418:e8e3
2292c19:dd:d9:dd:c25:c25:c418:e8e4/1282c19:dd:d9:dd:c25:c25:c418:e8e4
2302c19:dd:d9:dd:c25:c25:c418:e8e5/1282c19:dd:d9:dd:c25:c25:c418:e8e5
2312c19:dd:d9:dd:c25:c25:c418:e8e6/1282c19:dd:d9:dd:c25:c25:c418:e8e6
2322c19:dd:d9:dd:c25:c25:c418:e8e7/1282c19:dd:d9:dd:c25:c25:c418:e8e7
2332c19:dd:d9:dd:c25:c25:c418:e8e8/1282c19:dd:d9:dd:c25:c25:c418:e8e8
2342c19:dd:d9:dd:c25:c25:c418:e8e9/1282c19:dd:d9:dd:c25:c25:c418:e8e9
2352c19:dd:d9:dd:c25:c25:c418:e8ea/1282c19:dd:d9:dd:c25:c25:c418:e8ea
2362c19:dd:d9:dd:c25:c25:c418:e8eb/1282c19:dd:d9:dd:c25:c25:c418:e8eb
2372c19:dd:d9:dd:c25:c25:c418:e8ec/1282c19:dd:d9:dd:c25:c25:c418:e8ec
2382c19:dd:d9:dd:c25:c25:c418:e8ed/1282c19:dd:d9:dd:c25:c25:c418:e8ed
2392c19:dd:d9:dd:c25:c25:c418:e8ee/1282c19:dd:d9:dd:c25:c25:c418:e8ee
2402c19:dd:d9:dd:c25:c25:c418:e8ef/1282c19:dd:d9:dd:c25:c25:c418:e8ef
2412c19:dd:d9:dd:c25:c25:c418:e8f0/1282c19:dd:d9:dd:c25:c25:c418:e8f0
2422c19:dd:d9:dd:c25:c25:c418:e8f1/1282c19:dd:d9:dd:c25:c25:c418:e8f1
2432c19:dd:d9:dd:c25:c25:c418:e8f2/1282c19:dd:d9:dd:c25:c25:c418:e8f2
2442c19:dd:d9:dd:c25:c25:c418:e8f3/1282c19:dd:d9:dd:c25:c25:c418:e8f3
2452c19:dd:d9:dd:c25:c25:c418:e8f4/1282c19:dd:d9:dd:c25:c25:c418:e8f4
2462c19:dd:d9:dd:c25:c25:c418:e8f5/1282c19:dd:d9:dd:c25:c25:c418:e8f5
2472c19:dd:d9:dd:c25:c25:c418:e8f6/1282c19:dd:d9:dd:c25:c25:c418:e8f6
2482c19:dd:d9:dd:c25:c25:c418:e8f7/1282c19:dd:d9:dd:c25:c25:c418:e8f7
2492c19:dd:d9:dd:c25:c25:c418:e8f8/1282c19:dd:d9:dd:c25:c25:c418:e8f8
2502c19:dd:d9:dd:c25:c25:c418:e8f9/1282c19:dd:d9:dd:c25:c25:c418:e8f9
2512c19:dd:d9:dd:c25:c25:c418:e8fa/1282c19:dd:d9:dd:c25:c25:c418:e8fa
2522c19:dd:d9:dd:c25:c25:c418:e8fb/1282c19:dd:d9:dd:c25:c25:c418:e8fb
2532c19:dd:d9:dd:c25:c25:c418:e8fc/1282c19:dd:d9:dd:c25:c25:c418:e8fc
2542c19:dd:d9:dd:c25:c25:c418:e8fd/1282c19:dd:d9:dd:c25:c25:c418:e8fd
2552c19:dd:d9:dd:c25:c25:c418:e8fe/1282c19:dd:d9:dd:c25:c25:c418:e8fe
2562c19:dd:d9:dd:c25:c25:c418:e8ff/1282c19:dd:d9:dd:c25:c25:c418:e8ff

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.