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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:5900/120
First address
2c19:dd:d9:dd:c25:c25:94de:5900
Last address
2c19:dd:d9:dd:c25:c25:94de:59ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:5900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.5.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:5900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:5900/1282c19:dd:d9:dd:c25:c25:94de:5900
22c19:dd:d9:dd:c25:c25:94de:5901/1282c19:dd:d9:dd:c25:c25:94de:5901
32c19:dd:d9:dd:c25:c25:94de:5902/1282c19:dd:d9:dd:c25:c25:94de:5902
42c19:dd:d9:dd:c25:c25:94de:5903/1282c19:dd:d9:dd:c25:c25:94de:5903
52c19:dd:d9:dd:c25:c25:94de:5904/1282c19:dd:d9:dd:c25:c25:94de:5904
62c19:dd:d9:dd:c25:c25:94de:5905/1282c19:dd:d9:dd:c25:c25:94de:5905
72c19:dd:d9:dd:c25:c25:94de:5906/1282c19:dd:d9:dd:c25:c25:94de:5906
82c19:dd:d9:dd:c25:c25:94de:5907/1282c19:dd:d9:dd:c25:c25:94de:5907
92c19:dd:d9:dd:c25:c25:94de:5908/1282c19:dd:d9:dd:c25:c25:94de:5908
102c19:dd:d9:dd:c25:c25:94de:5909/1282c19:dd:d9:dd:c25:c25:94de:5909
112c19:dd:d9:dd:c25:c25:94de:590a/1282c19:dd:d9:dd:c25:c25:94de:590a
122c19:dd:d9:dd:c25:c25:94de:590b/1282c19:dd:d9:dd:c25:c25:94de:590b
132c19:dd:d9:dd:c25:c25:94de:590c/1282c19:dd:d9:dd:c25:c25:94de:590c
142c19:dd:d9:dd:c25:c25:94de:590d/1282c19:dd:d9:dd:c25:c25:94de:590d
152c19:dd:d9:dd:c25:c25:94de:590e/1282c19:dd:d9:dd:c25:c25:94de:590e
162c19:dd:d9:dd:c25:c25:94de:590f/1282c19:dd:d9:dd:c25:c25:94de:590f
172c19:dd:d9:dd:c25:c25:94de:5910/1282c19:dd:d9:dd:c25:c25:94de:5910
182c19:dd:d9:dd:c25:c25:94de:5911/1282c19:dd:d9:dd:c25:c25:94de:5911
192c19:dd:d9:dd:c25:c25:94de:5912/1282c19:dd:d9:dd:c25:c25:94de:5912
202c19:dd:d9:dd:c25:c25:94de:5913/1282c19:dd:d9:dd:c25:c25:94de:5913
212c19:dd:d9:dd:c25:c25:94de:5914/1282c19:dd:d9:dd:c25:c25:94de:5914
222c19:dd:d9:dd:c25:c25:94de:5915/1282c19:dd:d9:dd:c25:c25:94de:5915
232c19:dd:d9:dd:c25:c25:94de:5916/1282c19:dd:d9:dd:c25:c25:94de:5916
242c19:dd:d9:dd:c25:c25:94de:5917/1282c19:dd:d9:dd:c25:c25:94de:5917
252c19:dd:d9:dd:c25:c25:94de:5918/1282c19:dd:d9:dd:c25:c25:94de:5918
262c19:dd:d9:dd:c25:c25:94de:5919/1282c19:dd:d9:dd:c25:c25:94de:5919
272c19:dd:d9:dd:c25:c25:94de:591a/1282c19:dd:d9:dd:c25:c25:94de:591a
282c19:dd:d9:dd:c25:c25:94de:591b/1282c19:dd:d9:dd:c25:c25:94de:591b
292c19:dd:d9:dd:c25:c25:94de:591c/1282c19:dd:d9:dd:c25:c25:94de:591c
302c19:dd:d9:dd:c25:c25:94de:591d/1282c19:dd:d9:dd:c25:c25:94de:591d
312c19:dd:d9:dd:c25:c25:94de:591e/1282c19:dd:d9:dd:c25:c25:94de:591e
322c19:dd:d9:dd:c25:c25:94de:591f/1282c19:dd:d9:dd:c25:c25:94de:591f
332c19:dd:d9:dd:c25:c25:94de:5920/1282c19:dd:d9:dd:c25:c25:94de:5920
342c19:dd:d9:dd:c25:c25:94de:5921/1282c19:dd:d9:dd:c25:c25:94de:5921
352c19:dd:d9:dd:c25:c25:94de:5922/1282c19:dd:d9:dd:c25:c25:94de:5922
362c19:dd:d9:dd:c25:c25:94de:5923/1282c19:dd:d9:dd:c25:c25:94de:5923
372c19:dd:d9:dd:c25:c25:94de:5924/1282c19:dd:d9:dd:c25:c25:94de:5924
382c19:dd:d9:dd:c25:c25:94de:5925/1282c19:dd:d9:dd:c25:c25:94de:5925
392c19:dd:d9:dd:c25:c25:94de:5926/1282c19:dd:d9:dd:c25:c25:94de:5926
402c19:dd:d9:dd:c25:c25:94de:5927/1282c19:dd:d9:dd:c25:c25:94de:5927
412c19:dd:d9:dd:c25:c25:94de:5928/1282c19:dd:d9:dd:c25:c25:94de:5928
422c19:dd:d9:dd:c25:c25:94de:5929/1282c19:dd:d9:dd:c25:c25:94de:5929
432c19:dd:d9:dd:c25:c25:94de:592a/1282c19:dd:d9:dd:c25:c25:94de:592a
442c19:dd:d9:dd:c25:c25:94de:592b/1282c19:dd:d9:dd:c25:c25:94de:592b
452c19:dd:d9:dd:c25:c25:94de:592c/1282c19:dd:d9:dd:c25:c25:94de:592c
462c19:dd:d9:dd:c25:c25:94de:592d/1282c19:dd:d9:dd:c25:c25:94de:592d
472c19:dd:d9:dd:c25:c25:94de:592e/1282c19:dd:d9:dd:c25:c25:94de:592e
482c19:dd:d9:dd:c25:c25:94de:592f/1282c19:dd:d9:dd:c25:c25:94de:592f
492c19:dd:d9:dd:c25:c25:94de:5930/1282c19:dd:d9:dd:c25:c25:94de:5930
502c19:dd:d9:dd:c25:c25:94de:5931/1282c19:dd:d9:dd:c25:c25:94de:5931
512c19:dd:d9:dd:c25:c25:94de:5932/1282c19:dd:d9:dd:c25:c25:94de:5932
522c19:dd:d9:dd:c25:c25:94de:5933/1282c19:dd:d9:dd:c25:c25:94de:5933
532c19:dd:d9:dd:c25:c25:94de:5934/1282c19:dd:d9:dd:c25:c25:94de:5934
542c19:dd:d9:dd:c25:c25:94de:5935/1282c19:dd:d9:dd:c25:c25:94de:5935
552c19:dd:d9:dd:c25:c25:94de:5936/1282c19:dd:d9:dd:c25:c25:94de:5936
562c19:dd:d9:dd:c25:c25:94de:5937/1282c19:dd:d9:dd:c25:c25:94de:5937
572c19:dd:d9:dd:c25:c25:94de:5938/1282c19:dd:d9:dd:c25:c25:94de:5938
582c19:dd:d9:dd:c25:c25:94de:5939/1282c19:dd:d9:dd:c25:c25:94de:5939
592c19:dd:d9:dd:c25:c25:94de:593a/1282c19:dd:d9:dd:c25:c25:94de:593a
602c19:dd:d9:dd:c25:c25:94de:593b/1282c19:dd:d9:dd:c25:c25:94de:593b
612c19:dd:d9:dd:c25:c25:94de:593c/1282c19:dd:d9:dd:c25:c25:94de:593c
622c19:dd:d9:dd:c25:c25:94de:593d/1282c19:dd:d9:dd:c25:c25:94de:593d
632c19:dd:d9:dd:c25:c25:94de:593e/1282c19:dd:d9:dd:c25:c25:94de:593e
642c19:dd:d9:dd:c25:c25:94de:593f/1282c19:dd:d9:dd:c25:c25:94de:593f
652c19:dd:d9:dd:c25:c25:94de:5940/1282c19:dd:d9:dd:c25:c25:94de:5940
662c19:dd:d9:dd:c25:c25:94de:5941/1282c19:dd:d9:dd:c25:c25:94de:5941
672c19:dd:d9:dd:c25:c25:94de:5942/1282c19:dd:d9:dd:c25:c25:94de:5942
682c19:dd:d9:dd:c25:c25:94de:5943/1282c19:dd:d9:dd:c25:c25:94de:5943
692c19:dd:d9:dd:c25:c25:94de:5944/1282c19:dd:d9:dd:c25:c25:94de:5944
702c19:dd:d9:dd:c25:c25:94de:5945/1282c19:dd:d9:dd:c25:c25:94de:5945
712c19:dd:d9:dd:c25:c25:94de:5946/1282c19:dd:d9:dd:c25:c25:94de:5946
722c19:dd:d9:dd:c25:c25:94de:5947/1282c19:dd:d9:dd:c25:c25:94de:5947
732c19:dd:d9:dd:c25:c25:94de:5948/1282c19:dd:d9:dd:c25:c25:94de:5948
742c19:dd:d9:dd:c25:c25:94de:5949/1282c19:dd:d9:dd:c25:c25:94de:5949
752c19:dd:d9:dd:c25:c25:94de:594a/1282c19:dd:d9:dd:c25:c25:94de:594a
762c19:dd:d9:dd:c25:c25:94de:594b/1282c19:dd:d9:dd:c25:c25:94de:594b
772c19:dd:d9:dd:c25:c25:94de:594c/1282c19:dd:d9:dd:c25:c25:94de:594c
782c19:dd:d9:dd:c25:c25:94de:594d/1282c19:dd:d9:dd:c25:c25:94de:594d
792c19:dd:d9:dd:c25:c25:94de:594e/1282c19:dd:d9:dd:c25:c25:94de:594e
802c19:dd:d9:dd:c25:c25:94de:594f/1282c19:dd:d9:dd:c25:c25:94de:594f
812c19:dd:d9:dd:c25:c25:94de:5950/1282c19:dd:d9:dd:c25:c25:94de:5950
822c19:dd:d9:dd:c25:c25:94de:5951/1282c19:dd:d9:dd:c25:c25:94de:5951
832c19:dd:d9:dd:c25:c25:94de:5952/1282c19:dd:d9:dd:c25:c25:94de:5952
842c19:dd:d9:dd:c25:c25:94de:5953/1282c19:dd:d9:dd:c25:c25:94de:5953
852c19:dd:d9:dd:c25:c25:94de:5954/1282c19:dd:d9:dd:c25:c25:94de:5954
862c19:dd:d9:dd:c25:c25:94de:5955/1282c19:dd:d9:dd:c25:c25:94de:5955
872c19:dd:d9:dd:c25:c25:94de:5956/1282c19:dd:d9:dd:c25:c25:94de:5956
882c19:dd:d9:dd:c25:c25:94de:5957/1282c19:dd:d9:dd:c25:c25:94de:5957
892c19:dd:d9:dd:c25:c25:94de:5958/1282c19:dd:d9:dd:c25:c25:94de:5958
902c19:dd:d9:dd:c25:c25:94de:5959/1282c19:dd:d9:dd:c25:c25:94de:5959
912c19:dd:d9:dd:c25:c25:94de:595a/1282c19:dd:d9:dd:c25:c25:94de:595a
922c19:dd:d9:dd:c25:c25:94de:595b/1282c19:dd:d9:dd:c25:c25:94de:595b
932c19:dd:d9:dd:c25:c25:94de:595c/1282c19:dd:d9:dd:c25:c25:94de:595c
942c19:dd:d9:dd:c25:c25:94de:595d/1282c19:dd:d9:dd:c25:c25:94de:595d
952c19:dd:d9:dd:c25:c25:94de:595e/1282c19:dd:d9:dd:c25:c25:94de:595e
962c19:dd:d9:dd:c25:c25:94de:595f/1282c19:dd:d9:dd:c25:c25:94de:595f
972c19:dd:d9:dd:c25:c25:94de:5960/1282c19:dd:d9:dd:c25:c25:94de:5960
982c19:dd:d9:dd:c25:c25:94de:5961/1282c19:dd:d9:dd:c25:c25:94de:5961
992c19:dd:d9:dd:c25:c25:94de:5962/1282c19:dd:d9:dd:c25:c25:94de:5962
1002c19:dd:d9:dd:c25:c25:94de:5963/1282c19:dd:d9:dd:c25:c25:94de:5963
1012c19:dd:d9:dd:c25:c25:94de:5964/1282c19:dd:d9:dd:c25:c25:94de:5964
1022c19:dd:d9:dd:c25:c25:94de:5965/1282c19:dd:d9:dd:c25:c25:94de:5965
1032c19:dd:d9:dd:c25:c25:94de:5966/1282c19:dd:d9:dd:c25:c25:94de:5966
1042c19:dd:d9:dd:c25:c25:94de:5967/1282c19:dd:d9:dd:c25:c25:94de:5967
1052c19:dd:d9:dd:c25:c25:94de:5968/1282c19:dd:d9:dd:c25:c25:94de:5968
1062c19:dd:d9:dd:c25:c25:94de:5969/1282c19:dd:d9:dd:c25:c25:94de:5969
1072c19:dd:d9:dd:c25:c25:94de:596a/1282c19:dd:d9:dd:c25:c25:94de:596a
1082c19:dd:d9:dd:c25:c25:94de:596b/1282c19:dd:d9:dd:c25:c25:94de:596b
1092c19:dd:d9:dd:c25:c25:94de:596c/1282c19:dd:d9:dd:c25:c25:94de:596c
1102c19:dd:d9:dd:c25:c25:94de:596d/1282c19:dd:d9:dd:c25:c25:94de:596d
1112c19:dd:d9:dd:c25:c25:94de:596e/1282c19:dd:d9:dd:c25:c25:94de:596e
1122c19:dd:d9:dd:c25:c25:94de:596f/1282c19:dd:d9:dd:c25:c25:94de:596f
1132c19:dd:d9:dd:c25:c25:94de:5970/1282c19:dd:d9:dd:c25:c25:94de:5970
1142c19:dd:d9:dd:c25:c25:94de:5971/1282c19:dd:d9:dd:c25:c25:94de:5971
1152c19:dd:d9:dd:c25:c25:94de:5972/1282c19:dd:d9:dd:c25:c25:94de:5972
1162c19:dd:d9:dd:c25:c25:94de:5973/1282c19:dd:d9:dd:c25:c25:94de:5973
1172c19:dd:d9:dd:c25:c25:94de:5974/1282c19:dd:d9:dd:c25:c25:94de:5974
1182c19:dd:d9:dd:c25:c25:94de:5975/1282c19:dd:d9:dd:c25:c25:94de:5975
1192c19:dd:d9:dd:c25:c25:94de:5976/1282c19:dd:d9:dd:c25:c25:94de:5976
1202c19:dd:d9:dd:c25:c25:94de:5977/1282c19:dd:d9:dd:c25:c25:94de:5977
1212c19:dd:d9:dd:c25:c25:94de:5978/1282c19:dd:d9:dd:c25:c25:94de:5978
1222c19:dd:d9:dd:c25:c25:94de:5979/1282c19:dd:d9:dd:c25:c25:94de:5979
1232c19:dd:d9:dd:c25:c25:94de:597a/1282c19:dd:d9:dd:c25:c25:94de:597a
1242c19:dd:d9:dd:c25:c25:94de:597b/1282c19:dd:d9:dd:c25:c25:94de:597b
1252c19:dd:d9:dd:c25:c25:94de:597c/1282c19:dd:d9:dd:c25:c25:94de:597c
1262c19:dd:d9:dd:c25:c25:94de:597d/1282c19:dd:d9:dd:c25:c25:94de:597d
1272c19:dd:d9:dd:c25:c25:94de:597e/1282c19:dd:d9:dd:c25:c25:94de:597e
1282c19:dd:d9:dd:c25:c25:94de:597f/1282c19:dd:d9:dd:c25:c25:94de:597f
1292c19:dd:d9:dd:c25:c25:94de:5980/1282c19:dd:d9:dd:c25:c25:94de:5980
1302c19:dd:d9:dd:c25:c25:94de:5981/1282c19:dd:d9:dd:c25:c25:94de:5981
1312c19:dd:d9:dd:c25:c25:94de:5982/1282c19:dd:d9:dd:c25:c25:94de:5982
1322c19:dd:d9:dd:c25:c25:94de:5983/1282c19:dd:d9:dd:c25:c25:94de:5983
1332c19:dd:d9:dd:c25:c25:94de:5984/1282c19:dd:d9:dd:c25:c25:94de:5984
1342c19:dd:d9:dd:c25:c25:94de:5985/1282c19:dd:d9:dd:c25:c25:94de:5985
1352c19:dd:d9:dd:c25:c25:94de:5986/1282c19:dd:d9:dd:c25:c25:94de:5986
1362c19:dd:d9:dd:c25:c25:94de:5987/1282c19:dd:d9:dd:c25:c25:94de:5987
1372c19:dd:d9:dd:c25:c25:94de:5988/1282c19:dd:d9:dd:c25:c25:94de:5988
1382c19:dd:d9:dd:c25:c25:94de:5989/1282c19:dd:d9:dd:c25:c25:94de:5989
1392c19:dd:d9:dd:c25:c25:94de:598a/1282c19:dd:d9:dd:c25:c25:94de:598a
1402c19:dd:d9:dd:c25:c25:94de:598b/1282c19:dd:d9:dd:c25:c25:94de:598b
1412c19:dd:d9:dd:c25:c25:94de:598c/1282c19:dd:d9:dd:c25:c25:94de:598c
1422c19:dd:d9:dd:c25:c25:94de:598d/1282c19:dd:d9:dd:c25:c25:94de:598d
1432c19:dd:d9:dd:c25:c25:94de:598e/1282c19:dd:d9:dd:c25:c25:94de:598e
1442c19:dd:d9:dd:c25:c25:94de:598f/1282c19:dd:d9:dd:c25:c25:94de:598f
1452c19:dd:d9:dd:c25:c25:94de:5990/1282c19:dd:d9:dd:c25:c25:94de:5990
1462c19:dd:d9:dd:c25:c25:94de:5991/1282c19:dd:d9:dd:c25:c25:94de:5991
1472c19:dd:d9:dd:c25:c25:94de:5992/1282c19:dd:d9:dd:c25:c25:94de:5992
1482c19:dd:d9:dd:c25:c25:94de:5993/1282c19:dd:d9:dd:c25:c25:94de:5993
1492c19:dd:d9:dd:c25:c25:94de:5994/1282c19:dd:d9:dd:c25:c25:94de:5994
1502c19:dd:d9:dd:c25:c25:94de:5995/1282c19:dd:d9:dd:c25:c25:94de:5995
1512c19:dd:d9:dd:c25:c25:94de:5996/1282c19:dd:d9:dd:c25:c25:94de:5996
1522c19:dd:d9:dd:c25:c25:94de:5997/1282c19:dd:d9:dd:c25:c25:94de:5997
1532c19:dd:d9:dd:c25:c25:94de:5998/1282c19:dd:d9:dd:c25:c25:94de:5998
1542c19:dd:d9:dd:c25:c25:94de:5999/1282c19:dd:d9:dd:c25:c25:94de:5999
1552c19:dd:d9:dd:c25:c25:94de:599a/1282c19:dd:d9:dd:c25:c25:94de:599a
1562c19:dd:d9:dd:c25:c25:94de:599b/1282c19:dd:d9:dd:c25:c25:94de:599b
1572c19:dd:d9:dd:c25:c25:94de:599c/1282c19:dd:d9:dd:c25:c25:94de:599c
1582c19:dd:d9:dd:c25:c25:94de:599d/1282c19:dd:d9:dd:c25:c25:94de:599d
1592c19:dd:d9:dd:c25:c25:94de:599e/1282c19:dd:d9:dd:c25:c25:94de:599e
1602c19:dd:d9:dd:c25:c25:94de:599f/1282c19:dd:d9:dd:c25:c25:94de:599f
1612c19:dd:d9:dd:c25:c25:94de:59a0/1282c19:dd:d9:dd:c25:c25:94de:59a0
1622c19:dd:d9:dd:c25:c25:94de:59a1/1282c19:dd:d9:dd:c25:c25:94de:59a1
1632c19:dd:d9:dd:c25:c25:94de:59a2/1282c19:dd:d9:dd:c25:c25:94de:59a2
1642c19:dd:d9:dd:c25:c25:94de:59a3/1282c19:dd:d9:dd:c25:c25:94de:59a3
1652c19:dd:d9:dd:c25:c25:94de:59a4/1282c19:dd:d9:dd:c25:c25:94de:59a4
1662c19:dd:d9:dd:c25:c25:94de:59a5/1282c19:dd:d9:dd:c25:c25:94de:59a5
1672c19:dd:d9:dd:c25:c25:94de:59a6/1282c19:dd:d9:dd:c25:c25:94de:59a6
1682c19:dd:d9:dd:c25:c25:94de:59a7/1282c19:dd:d9:dd:c25:c25:94de:59a7
1692c19:dd:d9:dd:c25:c25:94de:59a8/1282c19:dd:d9:dd:c25:c25:94de:59a8
1702c19:dd:d9:dd:c25:c25:94de:59a9/1282c19:dd:d9:dd:c25:c25:94de:59a9
1712c19:dd:d9:dd:c25:c25:94de:59aa/1282c19:dd:d9:dd:c25:c25:94de:59aa
1722c19:dd:d9:dd:c25:c25:94de:59ab/1282c19:dd:d9:dd:c25:c25:94de:59ab
1732c19:dd:d9:dd:c25:c25:94de:59ac/1282c19:dd:d9:dd:c25:c25:94de:59ac
1742c19:dd:d9:dd:c25:c25:94de:59ad/1282c19:dd:d9:dd:c25:c25:94de:59ad
1752c19:dd:d9:dd:c25:c25:94de:59ae/1282c19:dd:d9:dd:c25:c25:94de:59ae
1762c19:dd:d9:dd:c25:c25:94de:59af/1282c19:dd:d9:dd:c25:c25:94de:59af
1772c19:dd:d9:dd:c25:c25:94de:59b0/1282c19:dd:d9:dd:c25:c25:94de:59b0
1782c19:dd:d9:dd:c25:c25:94de:59b1/1282c19:dd:d9:dd:c25:c25:94de:59b1
1792c19:dd:d9:dd:c25:c25:94de:59b2/1282c19:dd:d9:dd:c25:c25:94de:59b2
1802c19:dd:d9:dd:c25:c25:94de:59b3/1282c19:dd:d9:dd:c25:c25:94de:59b3
1812c19:dd:d9:dd:c25:c25:94de:59b4/1282c19:dd:d9:dd:c25:c25:94de:59b4
1822c19:dd:d9:dd:c25:c25:94de:59b5/1282c19:dd:d9:dd:c25:c25:94de:59b5
1832c19:dd:d9:dd:c25:c25:94de:59b6/1282c19:dd:d9:dd:c25:c25:94de:59b6
1842c19:dd:d9:dd:c25:c25:94de:59b7/1282c19:dd:d9:dd:c25:c25:94de:59b7
1852c19:dd:d9:dd:c25:c25:94de:59b8/1282c19:dd:d9:dd:c25:c25:94de:59b8
1862c19:dd:d9:dd:c25:c25:94de:59b9/1282c19:dd:d9:dd:c25:c25:94de:59b9
1872c19:dd:d9:dd:c25:c25:94de:59ba/1282c19:dd:d9:dd:c25:c25:94de:59ba
1882c19:dd:d9:dd:c25:c25:94de:59bb/1282c19:dd:d9:dd:c25:c25:94de:59bb
1892c19:dd:d9:dd:c25:c25:94de:59bc/1282c19:dd:d9:dd:c25:c25:94de:59bc
1902c19:dd:d9:dd:c25:c25:94de:59bd/1282c19:dd:d9:dd:c25:c25:94de:59bd
1912c19:dd:d9:dd:c25:c25:94de:59be/1282c19:dd:d9:dd:c25:c25:94de:59be
1922c19:dd:d9:dd:c25:c25:94de:59bf/1282c19:dd:d9:dd:c25:c25:94de:59bf
1932c19:dd:d9:dd:c25:c25:94de:59c0/1282c19:dd:d9:dd:c25:c25:94de:59c0
1942c19:dd:d9:dd:c25:c25:94de:59c1/1282c19:dd:d9:dd:c25:c25:94de:59c1
1952c19:dd:d9:dd:c25:c25:94de:59c2/1282c19:dd:d9:dd:c25:c25:94de:59c2
1962c19:dd:d9:dd:c25:c25:94de:59c3/1282c19:dd:d9:dd:c25:c25:94de:59c3
1972c19:dd:d9:dd:c25:c25:94de:59c4/1282c19:dd:d9:dd:c25:c25:94de:59c4
1982c19:dd:d9:dd:c25:c25:94de:59c5/1282c19:dd:d9:dd:c25:c25:94de:59c5
1992c19:dd:d9:dd:c25:c25:94de:59c6/1282c19:dd:d9:dd:c25:c25:94de:59c6
2002c19:dd:d9:dd:c25:c25:94de:59c7/1282c19:dd:d9:dd:c25:c25:94de:59c7
2012c19:dd:d9:dd:c25:c25:94de:59c8/1282c19:dd:d9:dd:c25:c25:94de:59c8
2022c19:dd:d9:dd:c25:c25:94de:59c9/1282c19:dd:d9:dd:c25:c25:94de:59c9
2032c19:dd:d9:dd:c25:c25:94de:59ca/1282c19:dd:d9:dd:c25:c25:94de:59ca
2042c19:dd:d9:dd:c25:c25:94de:59cb/1282c19:dd:d9:dd:c25:c25:94de:59cb
2052c19:dd:d9:dd:c25:c25:94de:59cc/1282c19:dd:d9:dd:c25:c25:94de:59cc
2062c19:dd:d9:dd:c25:c25:94de:59cd/1282c19:dd:d9:dd:c25:c25:94de:59cd
2072c19:dd:d9:dd:c25:c25:94de:59ce/1282c19:dd:d9:dd:c25:c25:94de:59ce
2082c19:dd:d9:dd:c25:c25:94de:59cf/1282c19:dd:d9:dd:c25:c25:94de:59cf
2092c19:dd:d9:dd:c25:c25:94de:59d0/1282c19:dd:d9:dd:c25:c25:94de:59d0
2102c19:dd:d9:dd:c25:c25:94de:59d1/1282c19:dd:d9:dd:c25:c25:94de:59d1
2112c19:dd:d9:dd:c25:c25:94de:59d2/1282c19:dd:d9:dd:c25:c25:94de:59d2
2122c19:dd:d9:dd:c25:c25:94de:59d3/1282c19:dd:d9:dd:c25:c25:94de:59d3
2132c19:dd:d9:dd:c25:c25:94de:59d4/1282c19:dd:d9:dd:c25:c25:94de:59d4
2142c19:dd:d9:dd:c25:c25:94de:59d5/1282c19:dd:d9:dd:c25:c25:94de:59d5
2152c19:dd:d9:dd:c25:c25:94de:59d6/1282c19:dd:d9:dd:c25:c25:94de:59d6
2162c19:dd:d9:dd:c25:c25:94de:59d7/1282c19:dd:d9:dd:c25:c25:94de:59d7
2172c19:dd:d9:dd:c25:c25:94de:59d8/1282c19:dd:d9:dd:c25:c25:94de:59d8
2182c19:dd:d9:dd:c25:c25:94de:59d9/1282c19:dd:d9:dd:c25:c25:94de:59d9
2192c19:dd:d9:dd:c25:c25:94de:59da/1282c19:dd:d9:dd:c25:c25:94de:59da
2202c19:dd:d9:dd:c25:c25:94de:59db/1282c19:dd:d9:dd:c25:c25:94de:59db
2212c19:dd:d9:dd:c25:c25:94de:59dc/1282c19:dd:d9:dd:c25:c25:94de:59dc
2222c19:dd:d9:dd:c25:c25:94de:59dd/1282c19:dd:d9:dd:c25:c25:94de:59dd
2232c19:dd:d9:dd:c25:c25:94de:59de/1282c19:dd:d9:dd:c25:c25:94de:59de
2242c19:dd:d9:dd:c25:c25:94de:59df/1282c19:dd:d9:dd:c25:c25:94de:59df
2252c19:dd:d9:dd:c25:c25:94de:59e0/1282c19:dd:d9:dd:c25:c25:94de:59e0
2262c19:dd:d9:dd:c25:c25:94de:59e1/1282c19:dd:d9:dd:c25:c25:94de:59e1
2272c19:dd:d9:dd:c25:c25:94de:59e2/1282c19:dd:d9:dd:c25:c25:94de:59e2
2282c19:dd:d9:dd:c25:c25:94de:59e3/1282c19:dd:d9:dd:c25:c25:94de:59e3
2292c19:dd:d9:dd:c25:c25:94de:59e4/1282c19:dd:d9:dd:c25:c25:94de:59e4
2302c19:dd:d9:dd:c25:c25:94de:59e5/1282c19:dd:d9:dd:c25:c25:94de:59e5
2312c19:dd:d9:dd:c25:c25:94de:59e6/1282c19:dd:d9:dd:c25:c25:94de:59e6
2322c19:dd:d9:dd:c25:c25:94de:59e7/1282c19:dd:d9:dd:c25:c25:94de:59e7
2332c19:dd:d9:dd:c25:c25:94de:59e8/1282c19:dd:d9:dd:c25:c25:94de:59e8
2342c19:dd:d9:dd:c25:c25:94de:59e9/1282c19:dd:d9:dd:c25:c25:94de:59e9
2352c19:dd:d9:dd:c25:c25:94de:59ea/1282c19:dd:d9:dd:c25:c25:94de:59ea
2362c19:dd:d9:dd:c25:c25:94de:59eb/1282c19:dd:d9:dd:c25:c25:94de:59eb
2372c19:dd:d9:dd:c25:c25:94de:59ec/1282c19:dd:d9:dd:c25:c25:94de:59ec
2382c19:dd:d9:dd:c25:c25:94de:59ed/1282c19:dd:d9:dd:c25:c25:94de:59ed
2392c19:dd:d9:dd:c25:c25:94de:59ee/1282c19:dd:d9:dd:c25:c25:94de:59ee
2402c19:dd:d9:dd:c25:c25:94de:59ef/1282c19:dd:d9:dd:c25:c25:94de:59ef
2412c19:dd:d9:dd:c25:c25:94de:59f0/1282c19:dd:d9:dd:c25:c25:94de:59f0
2422c19:dd:d9:dd:c25:c25:94de:59f1/1282c19:dd:d9:dd:c25:c25:94de:59f1
2432c19:dd:d9:dd:c25:c25:94de:59f2/1282c19:dd:d9:dd:c25:c25:94de:59f2
2442c19:dd:d9:dd:c25:c25:94de:59f3/1282c19:dd:d9:dd:c25:c25:94de:59f3
2452c19:dd:d9:dd:c25:c25:94de:59f4/1282c19:dd:d9:dd:c25:c25:94de:59f4
2462c19:dd:d9:dd:c25:c25:94de:59f5/1282c19:dd:d9:dd:c25:c25:94de:59f5
2472c19:dd:d9:dd:c25:c25:94de:59f6/1282c19:dd:d9:dd:c25:c25:94de:59f6
2482c19:dd:d9:dd:c25:c25:94de:59f7/1282c19:dd:d9:dd:c25:c25:94de:59f7
2492c19:dd:d9:dd:c25:c25:94de:59f8/1282c19:dd:d9:dd:c25:c25:94de:59f8
2502c19:dd:d9:dd:c25:c25:94de:59f9/1282c19:dd:d9:dd:c25:c25:94de:59f9
2512c19:dd:d9:dd:c25:c25:94de:59fa/1282c19:dd:d9:dd:c25:c25:94de:59fa
2522c19:dd:d9:dd:c25:c25:94de:59fb/1282c19:dd:d9:dd:c25:c25:94de:59fb
2532c19:dd:d9:dd:c25:c25:94de:59fc/1282c19:dd:d9:dd:c25:c25:94de:59fc
2542c19:dd:d9:dd:c25:c25:94de:59fd/1282c19:dd:d9:dd:c25:c25:94de:59fd
2552c19:dd:d9:dd:c25:c25:94de:59fe/1282c19:dd:d9:dd:c25:c25:94de:59fe
2562c19:dd:d9:dd:c25:c25:94de:59ff/1282c19:dd:d9:dd:c25:c25:94de:59ff

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.