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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:c25a:d00a:8900/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:8900
Last address
2c19:dd:d9:dd:c25:c25a:d00a:89ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:8900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.8.a.0.0.d.a.5.2.c.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:c25a:d00a:8900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:8900/1282c19:dd:d9:dd:c25:c25a:d00a:8900
22c19:dd:d9:dd:c25:c25a:d00a:8901/1282c19:dd:d9:dd:c25:c25a:d00a:8901
32c19:dd:d9:dd:c25:c25a:d00a:8902/1282c19:dd:d9:dd:c25:c25a:d00a:8902
42c19:dd:d9:dd:c25:c25a:d00a:8903/1282c19:dd:d9:dd:c25:c25a:d00a:8903
52c19:dd:d9:dd:c25:c25a:d00a:8904/1282c19:dd:d9:dd:c25:c25a:d00a:8904
62c19:dd:d9:dd:c25:c25a:d00a:8905/1282c19:dd:d9:dd:c25:c25a:d00a:8905
72c19:dd:d9:dd:c25:c25a:d00a:8906/1282c19:dd:d9:dd:c25:c25a:d00a:8906
82c19:dd:d9:dd:c25:c25a:d00a:8907/1282c19:dd:d9:dd:c25:c25a:d00a:8907
92c19:dd:d9:dd:c25:c25a:d00a:8908/1282c19:dd:d9:dd:c25:c25a:d00a:8908
102c19:dd:d9:dd:c25:c25a:d00a:8909/1282c19:dd:d9:dd:c25:c25a:d00a:8909
112c19:dd:d9:dd:c25:c25a:d00a:890a/1282c19:dd:d9:dd:c25:c25a:d00a:890a
122c19:dd:d9:dd:c25:c25a:d00a:890b/1282c19:dd:d9:dd:c25:c25a:d00a:890b
132c19:dd:d9:dd:c25:c25a:d00a:890c/1282c19:dd:d9:dd:c25:c25a:d00a:890c
142c19:dd:d9:dd:c25:c25a:d00a:890d/1282c19:dd:d9:dd:c25:c25a:d00a:890d
152c19:dd:d9:dd:c25:c25a:d00a:890e/1282c19:dd:d9:dd:c25:c25a:d00a:890e
162c19:dd:d9:dd:c25:c25a:d00a:890f/1282c19:dd:d9:dd:c25:c25a:d00a:890f
172c19:dd:d9:dd:c25:c25a:d00a:8910/1282c19:dd:d9:dd:c25:c25a:d00a:8910
182c19:dd:d9:dd:c25:c25a:d00a:8911/1282c19:dd:d9:dd:c25:c25a:d00a:8911
192c19:dd:d9:dd:c25:c25a:d00a:8912/1282c19:dd:d9:dd:c25:c25a:d00a:8912
202c19:dd:d9:dd:c25:c25a:d00a:8913/1282c19:dd:d9:dd:c25:c25a:d00a:8913
212c19:dd:d9:dd:c25:c25a:d00a:8914/1282c19:dd:d9:dd:c25:c25a:d00a:8914
222c19:dd:d9:dd:c25:c25a:d00a:8915/1282c19:dd:d9:dd:c25:c25a:d00a:8915
232c19:dd:d9:dd:c25:c25a:d00a:8916/1282c19:dd:d9:dd:c25:c25a:d00a:8916
242c19:dd:d9:dd:c25:c25a:d00a:8917/1282c19:dd:d9:dd:c25:c25a:d00a:8917
252c19:dd:d9:dd:c25:c25a:d00a:8918/1282c19:dd:d9:dd:c25:c25a:d00a:8918
262c19:dd:d9:dd:c25:c25a:d00a:8919/1282c19:dd:d9:dd:c25:c25a:d00a:8919
272c19:dd:d9:dd:c25:c25a:d00a:891a/1282c19:dd:d9:dd:c25:c25a:d00a:891a
282c19:dd:d9:dd:c25:c25a:d00a:891b/1282c19:dd:d9:dd:c25:c25a:d00a:891b
292c19:dd:d9:dd:c25:c25a:d00a:891c/1282c19:dd:d9:dd:c25:c25a:d00a:891c
302c19:dd:d9:dd:c25:c25a:d00a:891d/1282c19:dd:d9:dd:c25:c25a:d00a:891d
312c19:dd:d9:dd:c25:c25a:d00a:891e/1282c19:dd:d9:dd:c25:c25a:d00a:891e
322c19:dd:d9:dd:c25:c25a:d00a:891f/1282c19:dd:d9:dd:c25:c25a:d00a:891f
332c19:dd:d9:dd:c25:c25a:d00a:8920/1282c19:dd:d9:dd:c25:c25a:d00a:8920
342c19:dd:d9:dd:c25:c25a:d00a:8921/1282c19:dd:d9:dd:c25:c25a:d00a:8921
352c19:dd:d9:dd:c25:c25a:d00a:8922/1282c19:dd:d9:dd:c25:c25a:d00a:8922
362c19:dd:d9:dd:c25:c25a:d00a:8923/1282c19:dd:d9:dd:c25:c25a:d00a:8923
372c19:dd:d9:dd:c25:c25a:d00a:8924/1282c19:dd:d9:dd:c25:c25a:d00a:8924
382c19:dd:d9:dd:c25:c25a:d00a:8925/1282c19:dd:d9:dd:c25:c25a:d00a:8925
392c19:dd:d9:dd:c25:c25a:d00a:8926/1282c19:dd:d9:dd:c25:c25a:d00a:8926
402c19:dd:d9:dd:c25:c25a:d00a:8927/1282c19:dd:d9:dd:c25:c25a:d00a:8927
412c19:dd:d9:dd:c25:c25a:d00a:8928/1282c19:dd:d9:dd:c25:c25a:d00a:8928
422c19:dd:d9:dd:c25:c25a:d00a:8929/1282c19:dd:d9:dd:c25:c25a:d00a:8929
432c19:dd:d9:dd:c25:c25a:d00a:892a/1282c19:dd:d9:dd:c25:c25a:d00a:892a
442c19:dd:d9:dd:c25:c25a:d00a:892b/1282c19:dd:d9:dd:c25:c25a:d00a:892b
452c19:dd:d9:dd:c25:c25a:d00a:892c/1282c19:dd:d9:dd:c25:c25a:d00a:892c
462c19:dd:d9:dd:c25:c25a:d00a:892d/1282c19:dd:d9:dd:c25:c25a:d00a:892d
472c19:dd:d9:dd:c25:c25a:d00a:892e/1282c19:dd:d9:dd:c25:c25a:d00a:892e
482c19:dd:d9:dd:c25:c25a:d00a:892f/1282c19:dd:d9:dd:c25:c25a:d00a:892f
492c19:dd:d9:dd:c25:c25a:d00a:8930/1282c19:dd:d9:dd:c25:c25a:d00a:8930
502c19:dd:d9:dd:c25:c25a:d00a:8931/1282c19:dd:d9:dd:c25:c25a:d00a:8931
512c19:dd:d9:dd:c25:c25a:d00a:8932/1282c19:dd:d9:dd:c25:c25a:d00a:8932
522c19:dd:d9:dd:c25:c25a:d00a:8933/1282c19:dd:d9:dd:c25:c25a:d00a:8933
532c19:dd:d9:dd:c25:c25a:d00a:8934/1282c19:dd:d9:dd:c25:c25a:d00a:8934
542c19:dd:d9:dd:c25:c25a:d00a:8935/1282c19:dd:d9:dd:c25:c25a:d00a:8935
552c19:dd:d9:dd:c25:c25a:d00a:8936/1282c19:dd:d9:dd:c25:c25a:d00a:8936
562c19:dd:d9:dd:c25:c25a:d00a:8937/1282c19:dd:d9:dd:c25:c25a:d00a:8937
572c19:dd:d9:dd:c25:c25a:d00a:8938/1282c19:dd:d9:dd:c25:c25a:d00a:8938
582c19:dd:d9:dd:c25:c25a:d00a:8939/1282c19:dd:d9:dd:c25:c25a:d00a:8939
592c19:dd:d9:dd:c25:c25a:d00a:893a/1282c19:dd:d9:dd:c25:c25a:d00a:893a
602c19:dd:d9:dd:c25:c25a:d00a:893b/1282c19:dd:d9:dd:c25:c25a:d00a:893b
612c19:dd:d9:dd:c25:c25a:d00a:893c/1282c19:dd:d9:dd:c25:c25a:d00a:893c
622c19:dd:d9:dd:c25:c25a:d00a:893d/1282c19:dd:d9:dd:c25:c25a:d00a:893d
632c19:dd:d9:dd:c25:c25a:d00a:893e/1282c19:dd:d9:dd:c25:c25a:d00a:893e
642c19:dd:d9:dd:c25:c25a:d00a:893f/1282c19:dd:d9:dd:c25:c25a:d00a:893f
652c19:dd:d9:dd:c25:c25a:d00a:8940/1282c19:dd:d9:dd:c25:c25a:d00a:8940
662c19:dd:d9:dd:c25:c25a:d00a:8941/1282c19:dd:d9:dd:c25:c25a:d00a:8941
672c19:dd:d9:dd:c25:c25a:d00a:8942/1282c19:dd:d9:dd:c25:c25a:d00a:8942
682c19:dd:d9:dd:c25:c25a:d00a:8943/1282c19:dd:d9:dd:c25:c25a:d00a:8943
692c19:dd:d9:dd:c25:c25a:d00a:8944/1282c19:dd:d9:dd:c25:c25a:d00a:8944
702c19:dd:d9:dd:c25:c25a:d00a:8945/1282c19:dd:d9:dd:c25:c25a:d00a:8945
712c19:dd:d9:dd:c25:c25a:d00a:8946/1282c19:dd:d9:dd:c25:c25a:d00a:8946
722c19:dd:d9:dd:c25:c25a:d00a:8947/1282c19:dd:d9:dd:c25:c25a:d00a:8947
732c19:dd:d9:dd:c25:c25a:d00a:8948/1282c19:dd:d9:dd:c25:c25a:d00a:8948
742c19:dd:d9:dd:c25:c25a:d00a:8949/1282c19:dd:d9:dd:c25:c25a:d00a:8949
752c19:dd:d9:dd:c25:c25a:d00a:894a/1282c19:dd:d9:dd:c25:c25a:d00a:894a
762c19:dd:d9:dd:c25:c25a:d00a:894b/1282c19:dd:d9:dd:c25:c25a:d00a:894b
772c19:dd:d9:dd:c25:c25a:d00a:894c/1282c19:dd:d9:dd:c25:c25a:d00a:894c
782c19:dd:d9:dd:c25:c25a:d00a:894d/1282c19:dd:d9:dd:c25:c25a:d00a:894d
792c19:dd:d9:dd:c25:c25a:d00a:894e/1282c19:dd:d9:dd:c25:c25a:d00a:894e
802c19:dd:d9:dd:c25:c25a:d00a:894f/1282c19:dd:d9:dd:c25:c25a:d00a:894f
812c19:dd:d9:dd:c25:c25a:d00a:8950/1282c19:dd:d9:dd:c25:c25a:d00a:8950
822c19:dd:d9:dd:c25:c25a:d00a:8951/1282c19:dd:d9:dd:c25:c25a:d00a:8951
832c19:dd:d9:dd:c25:c25a:d00a:8952/1282c19:dd:d9:dd:c25:c25a:d00a:8952
842c19:dd:d9:dd:c25:c25a:d00a:8953/1282c19:dd:d9:dd:c25:c25a:d00a:8953
852c19:dd:d9:dd:c25:c25a:d00a:8954/1282c19:dd:d9:dd:c25:c25a:d00a:8954
862c19:dd:d9:dd:c25:c25a:d00a:8955/1282c19:dd:d9:dd:c25:c25a:d00a:8955
872c19:dd:d9:dd:c25:c25a:d00a:8956/1282c19:dd:d9:dd:c25:c25a:d00a:8956
882c19:dd:d9:dd:c25:c25a:d00a:8957/1282c19:dd:d9:dd:c25:c25a:d00a:8957
892c19:dd:d9:dd:c25:c25a:d00a:8958/1282c19:dd:d9:dd:c25:c25a:d00a:8958
902c19:dd:d9:dd:c25:c25a:d00a:8959/1282c19:dd:d9:dd:c25:c25a:d00a:8959
912c19:dd:d9:dd:c25:c25a:d00a:895a/1282c19:dd:d9:dd:c25:c25a:d00a:895a
922c19:dd:d9:dd:c25:c25a:d00a:895b/1282c19:dd:d9:dd:c25:c25a:d00a:895b
932c19:dd:d9:dd:c25:c25a:d00a:895c/1282c19:dd:d9:dd:c25:c25a:d00a:895c
942c19:dd:d9:dd:c25:c25a:d00a:895d/1282c19:dd:d9:dd:c25:c25a:d00a:895d
952c19:dd:d9:dd:c25:c25a:d00a:895e/1282c19:dd:d9:dd:c25:c25a:d00a:895e
962c19:dd:d9:dd:c25:c25a:d00a:895f/1282c19:dd:d9:dd:c25:c25a:d00a:895f
972c19:dd:d9:dd:c25:c25a:d00a:8960/1282c19:dd:d9:dd:c25:c25a:d00a:8960
982c19:dd:d9:dd:c25:c25a:d00a:8961/1282c19:dd:d9:dd:c25:c25a:d00a:8961
992c19:dd:d9:dd:c25:c25a:d00a:8962/1282c19:dd:d9:dd:c25:c25a:d00a:8962
1002c19:dd:d9:dd:c25:c25a:d00a:8963/1282c19:dd:d9:dd:c25:c25a:d00a:8963
1012c19:dd:d9:dd:c25:c25a:d00a:8964/1282c19:dd:d9:dd:c25:c25a:d00a:8964
1022c19:dd:d9:dd:c25:c25a:d00a:8965/1282c19:dd:d9:dd:c25:c25a:d00a:8965
1032c19:dd:d9:dd:c25:c25a:d00a:8966/1282c19:dd:d9:dd:c25:c25a:d00a:8966
1042c19:dd:d9:dd:c25:c25a:d00a:8967/1282c19:dd:d9:dd:c25:c25a:d00a:8967
1052c19:dd:d9:dd:c25:c25a:d00a:8968/1282c19:dd:d9:dd:c25:c25a:d00a:8968
1062c19:dd:d9:dd:c25:c25a:d00a:8969/1282c19:dd:d9:dd:c25:c25a:d00a:8969
1072c19:dd:d9:dd:c25:c25a:d00a:896a/1282c19:dd:d9:dd:c25:c25a:d00a:896a
1082c19:dd:d9:dd:c25:c25a:d00a:896b/1282c19:dd:d9:dd:c25:c25a:d00a:896b
1092c19:dd:d9:dd:c25:c25a:d00a:896c/1282c19:dd:d9:dd:c25:c25a:d00a:896c
1102c19:dd:d9:dd:c25:c25a:d00a:896d/1282c19:dd:d9:dd:c25:c25a:d00a:896d
1112c19:dd:d9:dd:c25:c25a:d00a:896e/1282c19:dd:d9:dd:c25:c25a:d00a:896e
1122c19:dd:d9:dd:c25:c25a:d00a:896f/1282c19:dd:d9:dd:c25:c25a:d00a:896f
1132c19:dd:d9:dd:c25:c25a:d00a:8970/1282c19:dd:d9:dd:c25:c25a:d00a:8970
1142c19:dd:d9:dd:c25:c25a:d00a:8971/1282c19:dd:d9:dd:c25:c25a:d00a:8971
1152c19:dd:d9:dd:c25:c25a:d00a:8972/1282c19:dd:d9:dd:c25:c25a:d00a:8972
1162c19:dd:d9:dd:c25:c25a:d00a:8973/1282c19:dd:d9:dd:c25:c25a:d00a:8973
1172c19:dd:d9:dd:c25:c25a:d00a:8974/1282c19:dd:d9:dd:c25:c25a:d00a:8974
1182c19:dd:d9:dd:c25:c25a:d00a:8975/1282c19:dd:d9:dd:c25:c25a:d00a:8975
1192c19:dd:d9:dd:c25:c25a:d00a:8976/1282c19:dd:d9:dd:c25:c25a:d00a:8976
1202c19:dd:d9:dd:c25:c25a:d00a:8977/1282c19:dd:d9:dd:c25:c25a:d00a:8977
1212c19:dd:d9:dd:c25:c25a:d00a:8978/1282c19:dd:d9:dd:c25:c25a:d00a:8978
1222c19:dd:d9:dd:c25:c25a:d00a:8979/1282c19:dd:d9:dd:c25:c25a:d00a:8979
1232c19:dd:d9:dd:c25:c25a:d00a:897a/1282c19:dd:d9:dd:c25:c25a:d00a:897a
1242c19:dd:d9:dd:c25:c25a:d00a:897b/1282c19:dd:d9:dd:c25:c25a:d00a:897b
1252c19:dd:d9:dd:c25:c25a:d00a:897c/1282c19:dd:d9:dd:c25:c25a:d00a:897c
1262c19:dd:d9:dd:c25:c25a:d00a:897d/1282c19:dd:d9:dd:c25:c25a:d00a:897d
1272c19:dd:d9:dd:c25:c25a:d00a:897e/1282c19:dd:d9:dd:c25:c25a:d00a:897e
1282c19:dd:d9:dd:c25:c25a:d00a:897f/1282c19:dd:d9:dd:c25:c25a:d00a:897f
1292c19:dd:d9:dd:c25:c25a:d00a:8980/1282c19:dd:d9:dd:c25:c25a:d00a:8980
1302c19:dd:d9:dd:c25:c25a:d00a:8981/1282c19:dd:d9:dd:c25:c25a:d00a:8981
1312c19:dd:d9:dd:c25:c25a:d00a:8982/1282c19:dd:d9:dd:c25:c25a:d00a:8982
1322c19:dd:d9:dd:c25:c25a:d00a:8983/1282c19:dd:d9:dd:c25:c25a:d00a:8983
1332c19:dd:d9:dd:c25:c25a:d00a:8984/1282c19:dd:d9:dd:c25:c25a:d00a:8984
1342c19:dd:d9:dd:c25:c25a:d00a:8985/1282c19:dd:d9:dd:c25:c25a:d00a:8985
1352c19:dd:d9:dd:c25:c25a:d00a:8986/1282c19:dd:d9:dd:c25:c25a:d00a:8986
1362c19:dd:d9:dd:c25:c25a:d00a:8987/1282c19:dd:d9:dd:c25:c25a:d00a:8987
1372c19:dd:d9:dd:c25:c25a:d00a:8988/1282c19:dd:d9:dd:c25:c25a:d00a:8988
1382c19:dd:d9:dd:c25:c25a:d00a:8989/1282c19:dd:d9:dd:c25:c25a:d00a:8989
1392c19:dd:d9:dd:c25:c25a:d00a:898a/1282c19:dd:d9:dd:c25:c25a:d00a:898a
1402c19:dd:d9:dd:c25:c25a:d00a:898b/1282c19:dd:d9:dd:c25:c25a:d00a:898b
1412c19:dd:d9:dd:c25:c25a:d00a:898c/1282c19:dd:d9:dd:c25:c25a:d00a:898c
1422c19:dd:d9:dd:c25:c25a:d00a:898d/1282c19:dd:d9:dd:c25:c25a:d00a:898d
1432c19:dd:d9:dd:c25:c25a:d00a:898e/1282c19:dd:d9:dd:c25:c25a:d00a:898e
1442c19:dd:d9:dd:c25:c25a:d00a:898f/1282c19:dd:d9:dd:c25:c25a:d00a:898f
1452c19:dd:d9:dd:c25:c25a:d00a:8990/1282c19:dd:d9:dd:c25:c25a:d00a:8990
1462c19:dd:d9:dd:c25:c25a:d00a:8991/1282c19:dd:d9:dd:c25:c25a:d00a:8991
1472c19:dd:d9:dd:c25:c25a:d00a:8992/1282c19:dd:d9:dd:c25:c25a:d00a:8992
1482c19:dd:d9:dd:c25:c25a:d00a:8993/1282c19:dd:d9:dd:c25:c25a:d00a:8993
1492c19:dd:d9:dd:c25:c25a:d00a:8994/1282c19:dd:d9:dd:c25:c25a:d00a:8994
1502c19:dd:d9:dd:c25:c25a:d00a:8995/1282c19:dd:d9:dd:c25:c25a:d00a:8995
1512c19:dd:d9:dd:c25:c25a:d00a:8996/1282c19:dd:d9:dd:c25:c25a:d00a:8996
1522c19:dd:d9:dd:c25:c25a:d00a:8997/1282c19:dd:d9:dd:c25:c25a:d00a:8997
1532c19:dd:d9:dd:c25:c25a:d00a:8998/1282c19:dd:d9:dd:c25:c25a:d00a:8998
1542c19:dd:d9:dd:c25:c25a:d00a:8999/1282c19:dd:d9:dd:c25:c25a:d00a:8999
1552c19:dd:d9:dd:c25:c25a:d00a:899a/1282c19:dd:d9:dd:c25:c25a:d00a:899a
1562c19:dd:d9:dd:c25:c25a:d00a:899b/1282c19:dd:d9:dd:c25:c25a:d00a:899b
1572c19:dd:d9:dd:c25:c25a:d00a:899c/1282c19:dd:d9:dd:c25:c25a:d00a:899c
1582c19:dd:d9:dd:c25:c25a:d00a:899d/1282c19:dd:d9:dd:c25:c25a:d00a:899d
1592c19:dd:d9:dd:c25:c25a:d00a:899e/1282c19:dd:d9:dd:c25:c25a:d00a:899e
1602c19:dd:d9:dd:c25:c25a:d00a:899f/1282c19:dd:d9:dd:c25:c25a:d00a:899f
1612c19:dd:d9:dd:c25:c25a:d00a:89a0/1282c19:dd:d9:dd:c25:c25a:d00a:89a0
1622c19:dd:d9:dd:c25:c25a:d00a:89a1/1282c19:dd:d9:dd:c25:c25a:d00a:89a1
1632c19:dd:d9:dd:c25:c25a:d00a:89a2/1282c19:dd:d9:dd:c25:c25a:d00a:89a2
1642c19:dd:d9:dd:c25:c25a:d00a:89a3/1282c19:dd:d9:dd:c25:c25a:d00a:89a3
1652c19:dd:d9:dd:c25:c25a:d00a:89a4/1282c19:dd:d9:dd:c25:c25a:d00a:89a4
1662c19:dd:d9:dd:c25:c25a:d00a:89a5/1282c19:dd:d9:dd:c25:c25a:d00a:89a5
1672c19:dd:d9:dd:c25:c25a:d00a:89a6/1282c19:dd:d9:dd:c25:c25a:d00a:89a6
1682c19:dd:d9:dd:c25:c25a:d00a:89a7/1282c19:dd:d9:dd:c25:c25a:d00a:89a7
1692c19:dd:d9:dd:c25:c25a:d00a:89a8/1282c19:dd:d9:dd:c25:c25a:d00a:89a8
1702c19:dd:d9:dd:c25:c25a:d00a:89a9/1282c19:dd:d9:dd:c25:c25a:d00a:89a9
1712c19:dd:d9:dd:c25:c25a:d00a:89aa/1282c19:dd:d9:dd:c25:c25a:d00a:89aa
1722c19:dd:d9:dd:c25:c25a:d00a:89ab/1282c19:dd:d9:dd:c25:c25a:d00a:89ab
1732c19:dd:d9:dd:c25:c25a:d00a:89ac/1282c19:dd:d9:dd:c25:c25a:d00a:89ac
1742c19:dd:d9:dd:c25:c25a:d00a:89ad/1282c19:dd:d9:dd:c25:c25a:d00a:89ad
1752c19:dd:d9:dd:c25:c25a:d00a:89ae/1282c19:dd:d9:dd:c25:c25a:d00a:89ae
1762c19:dd:d9:dd:c25:c25a:d00a:89af/1282c19:dd:d9:dd:c25:c25a:d00a:89af
1772c19:dd:d9:dd:c25:c25a:d00a:89b0/1282c19:dd:d9:dd:c25:c25a:d00a:89b0
1782c19:dd:d9:dd:c25:c25a:d00a:89b1/1282c19:dd:d9:dd:c25:c25a:d00a:89b1
1792c19:dd:d9:dd:c25:c25a:d00a:89b2/1282c19:dd:d9:dd:c25:c25a:d00a:89b2
1802c19:dd:d9:dd:c25:c25a:d00a:89b3/1282c19:dd:d9:dd:c25:c25a:d00a:89b3
1812c19:dd:d9:dd:c25:c25a:d00a:89b4/1282c19:dd:d9:dd:c25:c25a:d00a:89b4
1822c19:dd:d9:dd:c25:c25a:d00a:89b5/1282c19:dd:d9:dd:c25:c25a:d00a:89b5
1832c19:dd:d9:dd:c25:c25a:d00a:89b6/1282c19:dd:d9:dd:c25:c25a:d00a:89b6
1842c19:dd:d9:dd:c25:c25a:d00a:89b7/1282c19:dd:d9:dd:c25:c25a:d00a:89b7
1852c19:dd:d9:dd:c25:c25a:d00a:89b8/1282c19:dd:d9:dd:c25:c25a:d00a:89b8
1862c19:dd:d9:dd:c25:c25a:d00a:89b9/1282c19:dd:d9:dd:c25:c25a:d00a:89b9
1872c19:dd:d9:dd:c25:c25a:d00a:89ba/1282c19:dd:d9:dd:c25:c25a:d00a:89ba
1882c19:dd:d9:dd:c25:c25a:d00a:89bb/1282c19:dd:d9:dd:c25:c25a:d00a:89bb
1892c19:dd:d9:dd:c25:c25a:d00a:89bc/1282c19:dd:d9:dd:c25:c25a:d00a:89bc
1902c19:dd:d9:dd:c25:c25a:d00a:89bd/1282c19:dd:d9:dd:c25:c25a:d00a:89bd
1912c19:dd:d9:dd:c25:c25a:d00a:89be/1282c19:dd:d9:dd:c25:c25a:d00a:89be
1922c19:dd:d9:dd:c25:c25a:d00a:89bf/1282c19:dd:d9:dd:c25:c25a:d00a:89bf
1932c19:dd:d9:dd:c25:c25a:d00a:89c0/1282c19:dd:d9:dd:c25:c25a:d00a:89c0
1942c19:dd:d9:dd:c25:c25a:d00a:89c1/1282c19:dd:d9:dd:c25:c25a:d00a:89c1
1952c19:dd:d9:dd:c25:c25a:d00a:89c2/1282c19:dd:d9:dd:c25:c25a:d00a:89c2
1962c19:dd:d9:dd:c25:c25a:d00a:89c3/1282c19:dd:d9:dd:c25:c25a:d00a:89c3
1972c19:dd:d9:dd:c25:c25a:d00a:89c4/1282c19:dd:d9:dd:c25:c25a:d00a:89c4
1982c19:dd:d9:dd:c25:c25a:d00a:89c5/1282c19:dd:d9:dd:c25:c25a:d00a:89c5
1992c19:dd:d9:dd:c25:c25a:d00a:89c6/1282c19:dd:d9:dd:c25:c25a:d00a:89c6
2002c19:dd:d9:dd:c25:c25a:d00a:89c7/1282c19:dd:d9:dd:c25:c25a:d00a:89c7
2012c19:dd:d9:dd:c25:c25a:d00a:89c8/1282c19:dd:d9:dd:c25:c25a:d00a:89c8
2022c19:dd:d9:dd:c25:c25a:d00a:89c9/1282c19:dd:d9:dd:c25:c25a:d00a:89c9
2032c19:dd:d9:dd:c25:c25a:d00a:89ca/1282c19:dd:d9:dd:c25:c25a:d00a:89ca
2042c19:dd:d9:dd:c25:c25a:d00a:89cb/1282c19:dd:d9:dd:c25:c25a:d00a:89cb
2052c19:dd:d9:dd:c25:c25a:d00a:89cc/1282c19:dd:d9:dd:c25:c25a:d00a:89cc
2062c19:dd:d9:dd:c25:c25a:d00a:89cd/1282c19:dd:d9:dd:c25:c25a:d00a:89cd
2072c19:dd:d9:dd:c25:c25a:d00a:89ce/1282c19:dd:d9:dd:c25:c25a:d00a:89ce
2082c19:dd:d9:dd:c25:c25a:d00a:89cf/1282c19:dd:d9:dd:c25:c25a:d00a:89cf
2092c19:dd:d9:dd:c25:c25a:d00a:89d0/1282c19:dd:d9:dd:c25:c25a:d00a:89d0
2102c19:dd:d9:dd:c25:c25a:d00a:89d1/1282c19:dd:d9:dd:c25:c25a:d00a:89d1
2112c19:dd:d9:dd:c25:c25a:d00a:89d2/1282c19:dd:d9:dd:c25:c25a:d00a:89d2
2122c19:dd:d9:dd:c25:c25a:d00a:89d3/1282c19:dd:d9:dd:c25:c25a:d00a:89d3
2132c19:dd:d9:dd:c25:c25a:d00a:89d4/1282c19:dd:d9:dd:c25:c25a:d00a:89d4
2142c19:dd:d9:dd:c25:c25a:d00a:89d5/1282c19:dd:d9:dd:c25:c25a:d00a:89d5
2152c19:dd:d9:dd:c25:c25a:d00a:89d6/1282c19:dd:d9:dd:c25:c25a:d00a:89d6
2162c19:dd:d9:dd:c25:c25a:d00a:89d7/1282c19:dd:d9:dd:c25:c25a:d00a:89d7
2172c19:dd:d9:dd:c25:c25a:d00a:89d8/1282c19:dd:d9:dd:c25:c25a:d00a:89d8
2182c19:dd:d9:dd:c25:c25a:d00a:89d9/1282c19:dd:d9:dd:c25:c25a:d00a:89d9
2192c19:dd:d9:dd:c25:c25a:d00a:89da/1282c19:dd:d9:dd:c25:c25a:d00a:89da
2202c19:dd:d9:dd:c25:c25a:d00a:89db/1282c19:dd:d9:dd:c25:c25a:d00a:89db
2212c19:dd:d9:dd:c25:c25a:d00a:89dc/1282c19:dd:d9:dd:c25:c25a:d00a:89dc
2222c19:dd:d9:dd:c25:c25a:d00a:89dd/1282c19:dd:d9:dd:c25:c25a:d00a:89dd
2232c19:dd:d9:dd:c25:c25a:d00a:89de/1282c19:dd:d9:dd:c25:c25a:d00a:89de
2242c19:dd:d9:dd:c25:c25a:d00a:89df/1282c19:dd:d9:dd:c25:c25a:d00a:89df
2252c19:dd:d9:dd:c25:c25a:d00a:89e0/1282c19:dd:d9:dd:c25:c25a:d00a:89e0
2262c19:dd:d9:dd:c25:c25a:d00a:89e1/1282c19:dd:d9:dd:c25:c25a:d00a:89e1
2272c19:dd:d9:dd:c25:c25a:d00a:89e2/1282c19:dd:d9:dd:c25:c25a:d00a:89e2
2282c19:dd:d9:dd:c25:c25a:d00a:89e3/1282c19:dd:d9:dd:c25:c25a:d00a:89e3
2292c19:dd:d9:dd:c25:c25a:d00a:89e4/1282c19:dd:d9:dd:c25:c25a:d00a:89e4
2302c19:dd:d9:dd:c25:c25a:d00a:89e5/1282c19:dd:d9:dd:c25:c25a:d00a:89e5
2312c19:dd:d9:dd:c25:c25a:d00a:89e6/1282c19:dd:d9:dd:c25:c25a:d00a:89e6
2322c19:dd:d9:dd:c25:c25a:d00a:89e7/1282c19:dd:d9:dd:c25:c25a:d00a:89e7
2332c19:dd:d9:dd:c25:c25a:d00a:89e8/1282c19:dd:d9:dd:c25:c25a:d00a:89e8
2342c19:dd:d9:dd:c25:c25a:d00a:89e9/1282c19:dd:d9:dd:c25:c25a:d00a:89e9
2352c19:dd:d9:dd:c25:c25a:d00a:89ea/1282c19:dd:d9:dd:c25:c25a:d00a:89ea
2362c19:dd:d9:dd:c25:c25a:d00a:89eb/1282c19:dd:d9:dd:c25:c25a:d00a:89eb
2372c19:dd:d9:dd:c25:c25a:d00a:89ec/1282c19:dd:d9:dd:c25:c25a:d00a:89ec
2382c19:dd:d9:dd:c25:c25a:d00a:89ed/1282c19:dd:d9:dd:c25:c25a:d00a:89ed
2392c19:dd:d9:dd:c25:c25a:d00a:89ee/1282c19:dd:d9:dd:c25:c25a:d00a:89ee
2402c19:dd:d9:dd:c25:c25a:d00a:89ef/1282c19:dd:d9:dd:c25:c25a:d00a:89ef
2412c19:dd:d9:dd:c25:c25a:d00a:89f0/1282c19:dd:d9:dd:c25:c25a:d00a:89f0
2422c19:dd:d9:dd:c25:c25a:d00a:89f1/1282c19:dd:d9:dd:c25:c25a:d00a:89f1
2432c19:dd:d9:dd:c25:c25a:d00a:89f2/1282c19:dd:d9:dd:c25:c25a:d00a:89f2
2442c19:dd:d9:dd:c25:c25a:d00a:89f3/1282c19:dd:d9:dd:c25:c25a:d00a:89f3
2452c19:dd:d9:dd:c25:c25a:d00a:89f4/1282c19:dd:d9:dd:c25:c25a:d00a:89f4
2462c19:dd:d9:dd:c25:c25a:d00a:89f5/1282c19:dd:d9:dd:c25:c25a:d00a:89f5
2472c19:dd:d9:dd:c25:c25a:d00a:89f6/1282c19:dd:d9:dd:c25:c25a:d00a:89f6
2482c19:dd:d9:dd:c25:c25a:d00a:89f7/1282c19:dd:d9:dd:c25:c25a:d00a:89f7
2492c19:dd:d9:dd:c25:c25a:d00a:89f8/1282c19:dd:d9:dd:c25:c25a:d00a:89f8
2502c19:dd:d9:dd:c25:c25a:d00a:89f9/1282c19:dd:d9:dd:c25:c25a:d00a:89f9
2512c19:dd:d9:dd:c25:c25a:d00a:89fa/1282c19:dd:d9:dd:c25:c25a:d00a:89fa
2522c19:dd:d9:dd:c25:c25a:d00a:89fb/1282c19:dd:d9:dd:c25:c25a:d00a:89fb
2532c19:dd:d9:dd:c25:c25a:d00a:89fc/1282c19:dd:d9:dd:c25:c25a:d00a:89fc
2542c19:dd:d9:dd:c25:c25a:d00a:89fd/1282c19:dd:d9:dd:c25:c25a:d00a:89fd
2552c19:dd:d9:dd:c25:c25a:d00a:89fe/1282c19:dd:d9:dd:c25:c25a:d00a:89fe
2562c19:dd:d9:dd:c25:c25a:d00a:89ff/1282c19:dd:d9:dd:c25:c25a:d00a:89ff

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.