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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:4900/120
First address
2c19:dd:d9:dd:c25:c25:94de:4900
Last address
2c19:dd:d9:dd:c25:c25:94de:49ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:4900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.4.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:4900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:4900/1282c19:dd:d9:dd:c25:c25:94de:4900
22c19:dd:d9:dd:c25:c25:94de:4901/1282c19:dd:d9:dd:c25:c25:94de:4901
32c19:dd:d9:dd:c25:c25:94de:4902/1282c19:dd:d9:dd:c25:c25:94de:4902
42c19:dd:d9:dd:c25:c25:94de:4903/1282c19:dd:d9:dd:c25:c25:94de:4903
52c19:dd:d9:dd:c25:c25:94de:4904/1282c19:dd:d9:dd:c25:c25:94de:4904
62c19:dd:d9:dd:c25:c25:94de:4905/1282c19:dd:d9:dd:c25:c25:94de:4905
72c19:dd:d9:dd:c25:c25:94de:4906/1282c19:dd:d9:dd:c25:c25:94de:4906
82c19:dd:d9:dd:c25:c25:94de:4907/1282c19:dd:d9:dd:c25:c25:94de:4907
92c19:dd:d9:dd:c25:c25:94de:4908/1282c19:dd:d9:dd:c25:c25:94de:4908
102c19:dd:d9:dd:c25:c25:94de:4909/1282c19:dd:d9:dd:c25:c25:94de:4909
112c19:dd:d9:dd:c25:c25:94de:490a/1282c19:dd:d9:dd:c25:c25:94de:490a
122c19:dd:d9:dd:c25:c25:94de:490b/1282c19:dd:d9:dd:c25:c25:94de:490b
132c19:dd:d9:dd:c25:c25:94de:490c/1282c19:dd:d9:dd:c25:c25:94de:490c
142c19:dd:d9:dd:c25:c25:94de:490d/1282c19:dd:d9:dd:c25:c25:94de:490d
152c19:dd:d9:dd:c25:c25:94de:490e/1282c19:dd:d9:dd:c25:c25:94de:490e
162c19:dd:d9:dd:c25:c25:94de:490f/1282c19:dd:d9:dd:c25:c25:94de:490f
172c19:dd:d9:dd:c25:c25:94de:4910/1282c19:dd:d9:dd:c25:c25:94de:4910
182c19:dd:d9:dd:c25:c25:94de:4911/1282c19:dd:d9:dd:c25:c25:94de:4911
192c19:dd:d9:dd:c25:c25:94de:4912/1282c19:dd:d9:dd:c25:c25:94de:4912
202c19:dd:d9:dd:c25:c25:94de:4913/1282c19:dd:d9:dd:c25:c25:94de:4913
212c19:dd:d9:dd:c25:c25:94de:4914/1282c19:dd:d9:dd:c25:c25:94de:4914
222c19:dd:d9:dd:c25:c25:94de:4915/1282c19:dd:d9:dd:c25:c25:94de:4915
232c19:dd:d9:dd:c25:c25:94de:4916/1282c19:dd:d9:dd:c25:c25:94de:4916
242c19:dd:d9:dd:c25:c25:94de:4917/1282c19:dd:d9:dd:c25:c25:94de:4917
252c19:dd:d9:dd:c25:c25:94de:4918/1282c19:dd:d9:dd:c25:c25:94de:4918
262c19:dd:d9:dd:c25:c25:94de:4919/1282c19:dd:d9:dd:c25:c25:94de:4919
272c19:dd:d9:dd:c25:c25:94de:491a/1282c19:dd:d9:dd:c25:c25:94de:491a
282c19:dd:d9:dd:c25:c25:94de:491b/1282c19:dd:d9:dd:c25:c25:94de:491b
292c19:dd:d9:dd:c25:c25:94de:491c/1282c19:dd:d9:dd:c25:c25:94de:491c
302c19:dd:d9:dd:c25:c25:94de:491d/1282c19:dd:d9:dd:c25:c25:94de:491d
312c19:dd:d9:dd:c25:c25:94de:491e/1282c19:dd:d9:dd:c25:c25:94de:491e
322c19:dd:d9:dd:c25:c25:94de:491f/1282c19:dd:d9:dd:c25:c25:94de:491f
332c19:dd:d9:dd:c25:c25:94de:4920/1282c19:dd:d9:dd:c25:c25:94de:4920
342c19:dd:d9:dd:c25:c25:94de:4921/1282c19:dd:d9:dd:c25:c25:94de:4921
352c19:dd:d9:dd:c25:c25:94de:4922/1282c19:dd:d9:dd:c25:c25:94de:4922
362c19:dd:d9:dd:c25:c25:94de:4923/1282c19:dd:d9:dd:c25:c25:94de:4923
372c19:dd:d9:dd:c25:c25:94de:4924/1282c19:dd:d9:dd:c25:c25:94de:4924
382c19:dd:d9:dd:c25:c25:94de:4925/1282c19:dd:d9:dd:c25:c25:94de:4925
392c19:dd:d9:dd:c25:c25:94de:4926/1282c19:dd:d9:dd:c25:c25:94de:4926
402c19:dd:d9:dd:c25:c25:94de:4927/1282c19:dd:d9:dd:c25:c25:94de:4927
412c19:dd:d9:dd:c25:c25:94de:4928/1282c19:dd:d9:dd:c25:c25:94de:4928
422c19:dd:d9:dd:c25:c25:94de:4929/1282c19:dd:d9:dd:c25:c25:94de:4929
432c19:dd:d9:dd:c25:c25:94de:492a/1282c19:dd:d9:dd:c25:c25:94de:492a
442c19:dd:d9:dd:c25:c25:94de:492b/1282c19:dd:d9:dd:c25:c25:94de:492b
452c19:dd:d9:dd:c25:c25:94de:492c/1282c19:dd:d9:dd:c25:c25:94de:492c
462c19:dd:d9:dd:c25:c25:94de:492d/1282c19:dd:d9:dd:c25:c25:94de:492d
472c19:dd:d9:dd:c25:c25:94de:492e/1282c19:dd:d9:dd:c25:c25:94de:492e
482c19:dd:d9:dd:c25:c25:94de:492f/1282c19:dd:d9:dd:c25:c25:94de:492f
492c19:dd:d9:dd:c25:c25:94de:4930/1282c19:dd:d9:dd:c25:c25:94de:4930
502c19:dd:d9:dd:c25:c25:94de:4931/1282c19:dd:d9:dd:c25:c25:94de:4931
512c19:dd:d9:dd:c25:c25:94de:4932/1282c19:dd:d9:dd:c25:c25:94de:4932
522c19:dd:d9:dd:c25:c25:94de:4933/1282c19:dd:d9:dd:c25:c25:94de:4933
532c19:dd:d9:dd:c25:c25:94de:4934/1282c19:dd:d9:dd:c25:c25:94de:4934
542c19:dd:d9:dd:c25:c25:94de:4935/1282c19:dd:d9:dd:c25:c25:94de:4935
552c19:dd:d9:dd:c25:c25:94de:4936/1282c19:dd:d9:dd:c25:c25:94de:4936
562c19:dd:d9:dd:c25:c25:94de:4937/1282c19:dd:d9:dd:c25:c25:94de:4937
572c19:dd:d9:dd:c25:c25:94de:4938/1282c19:dd:d9:dd:c25:c25:94de:4938
582c19:dd:d9:dd:c25:c25:94de:4939/1282c19:dd:d9:dd:c25:c25:94de:4939
592c19:dd:d9:dd:c25:c25:94de:493a/1282c19:dd:d9:dd:c25:c25:94de:493a
602c19:dd:d9:dd:c25:c25:94de:493b/1282c19:dd:d9:dd:c25:c25:94de:493b
612c19:dd:d9:dd:c25:c25:94de:493c/1282c19:dd:d9:dd:c25:c25:94de:493c
622c19:dd:d9:dd:c25:c25:94de:493d/1282c19:dd:d9:dd:c25:c25:94de:493d
632c19:dd:d9:dd:c25:c25:94de:493e/1282c19:dd:d9:dd:c25:c25:94de:493e
642c19:dd:d9:dd:c25:c25:94de:493f/1282c19:dd:d9:dd:c25:c25:94de:493f
652c19:dd:d9:dd:c25:c25:94de:4940/1282c19:dd:d9:dd:c25:c25:94de:4940
662c19:dd:d9:dd:c25:c25:94de:4941/1282c19:dd:d9:dd:c25:c25:94de:4941
672c19:dd:d9:dd:c25:c25:94de:4942/1282c19:dd:d9:dd:c25:c25:94de:4942
682c19:dd:d9:dd:c25:c25:94de:4943/1282c19:dd:d9:dd:c25:c25:94de:4943
692c19:dd:d9:dd:c25:c25:94de:4944/1282c19:dd:d9:dd:c25:c25:94de:4944
702c19:dd:d9:dd:c25:c25:94de:4945/1282c19:dd:d9:dd:c25:c25:94de:4945
712c19:dd:d9:dd:c25:c25:94de:4946/1282c19:dd:d9:dd:c25:c25:94de:4946
722c19:dd:d9:dd:c25:c25:94de:4947/1282c19:dd:d9:dd:c25:c25:94de:4947
732c19:dd:d9:dd:c25:c25:94de:4948/1282c19:dd:d9:dd:c25:c25:94de:4948
742c19:dd:d9:dd:c25:c25:94de:4949/1282c19:dd:d9:dd:c25:c25:94de:4949
752c19:dd:d9:dd:c25:c25:94de:494a/1282c19:dd:d9:dd:c25:c25:94de:494a
762c19:dd:d9:dd:c25:c25:94de:494b/1282c19:dd:d9:dd:c25:c25:94de:494b
772c19:dd:d9:dd:c25:c25:94de:494c/1282c19:dd:d9:dd:c25:c25:94de:494c
782c19:dd:d9:dd:c25:c25:94de:494d/1282c19:dd:d9:dd:c25:c25:94de:494d
792c19:dd:d9:dd:c25:c25:94de:494e/1282c19:dd:d9:dd:c25:c25:94de:494e
802c19:dd:d9:dd:c25:c25:94de:494f/1282c19:dd:d9:dd:c25:c25:94de:494f
812c19:dd:d9:dd:c25:c25:94de:4950/1282c19:dd:d9:dd:c25:c25:94de:4950
822c19:dd:d9:dd:c25:c25:94de:4951/1282c19:dd:d9:dd:c25:c25:94de:4951
832c19:dd:d9:dd:c25:c25:94de:4952/1282c19:dd:d9:dd:c25:c25:94de:4952
842c19:dd:d9:dd:c25:c25:94de:4953/1282c19:dd:d9:dd:c25:c25:94de:4953
852c19:dd:d9:dd:c25:c25:94de:4954/1282c19:dd:d9:dd:c25:c25:94de:4954
862c19:dd:d9:dd:c25:c25:94de:4955/1282c19:dd:d9:dd:c25:c25:94de:4955
872c19:dd:d9:dd:c25:c25:94de:4956/1282c19:dd:d9:dd:c25:c25:94de:4956
882c19:dd:d9:dd:c25:c25:94de:4957/1282c19:dd:d9:dd:c25:c25:94de:4957
892c19:dd:d9:dd:c25:c25:94de:4958/1282c19:dd:d9:dd:c25:c25:94de:4958
902c19:dd:d9:dd:c25:c25:94de:4959/1282c19:dd:d9:dd:c25:c25:94de:4959
912c19:dd:d9:dd:c25:c25:94de:495a/1282c19:dd:d9:dd:c25:c25:94de:495a
922c19:dd:d9:dd:c25:c25:94de:495b/1282c19:dd:d9:dd:c25:c25:94de:495b
932c19:dd:d9:dd:c25:c25:94de:495c/1282c19:dd:d9:dd:c25:c25:94de:495c
942c19:dd:d9:dd:c25:c25:94de:495d/1282c19:dd:d9:dd:c25:c25:94de:495d
952c19:dd:d9:dd:c25:c25:94de:495e/1282c19:dd:d9:dd:c25:c25:94de:495e
962c19:dd:d9:dd:c25:c25:94de:495f/1282c19:dd:d9:dd:c25:c25:94de:495f
972c19:dd:d9:dd:c25:c25:94de:4960/1282c19:dd:d9:dd:c25:c25:94de:4960
982c19:dd:d9:dd:c25:c25:94de:4961/1282c19:dd:d9:dd:c25:c25:94de:4961
992c19:dd:d9:dd:c25:c25:94de:4962/1282c19:dd:d9:dd:c25:c25:94de:4962
1002c19:dd:d9:dd:c25:c25:94de:4963/1282c19:dd:d9:dd:c25:c25:94de:4963
1012c19:dd:d9:dd:c25:c25:94de:4964/1282c19:dd:d9:dd:c25:c25:94de:4964
1022c19:dd:d9:dd:c25:c25:94de:4965/1282c19:dd:d9:dd:c25:c25:94de:4965
1032c19:dd:d9:dd:c25:c25:94de:4966/1282c19:dd:d9:dd:c25:c25:94de:4966
1042c19:dd:d9:dd:c25:c25:94de:4967/1282c19:dd:d9:dd:c25:c25:94de:4967
1052c19:dd:d9:dd:c25:c25:94de:4968/1282c19:dd:d9:dd:c25:c25:94de:4968
1062c19:dd:d9:dd:c25:c25:94de:4969/1282c19:dd:d9:dd:c25:c25:94de:4969
1072c19:dd:d9:dd:c25:c25:94de:496a/1282c19:dd:d9:dd:c25:c25:94de:496a
1082c19:dd:d9:dd:c25:c25:94de:496b/1282c19:dd:d9:dd:c25:c25:94de:496b
1092c19:dd:d9:dd:c25:c25:94de:496c/1282c19:dd:d9:dd:c25:c25:94de:496c
1102c19:dd:d9:dd:c25:c25:94de:496d/1282c19:dd:d9:dd:c25:c25:94de:496d
1112c19:dd:d9:dd:c25:c25:94de:496e/1282c19:dd:d9:dd:c25:c25:94de:496e
1122c19:dd:d9:dd:c25:c25:94de:496f/1282c19:dd:d9:dd:c25:c25:94de:496f
1132c19:dd:d9:dd:c25:c25:94de:4970/1282c19:dd:d9:dd:c25:c25:94de:4970
1142c19:dd:d9:dd:c25:c25:94de:4971/1282c19:dd:d9:dd:c25:c25:94de:4971
1152c19:dd:d9:dd:c25:c25:94de:4972/1282c19:dd:d9:dd:c25:c25:94de:4972
1162c19:dd:d9:dd:c25:c25:94de:4973/1282c19:dd:d9:dd:c25:c25:94de:4973
1172c19:dd:d9:dd:c25:c25:94de:4974/1282c19:dd:d9:dd:c25:c25:94de:4974
1182c19:dd:d9:dd:c25:c25:94de:4975/1282c19:dd:d9:dd:c25:c25:94de:4975
1192c19:dd:d9:dd:c25:c25:94de:4976/1282c19:dd:d9:dd:c25:c25:94de:4976
1202c19:dd:d9:dd:c25:c25:94de:4977/1282c19:dd:d9:dd:c25:c25:94de:4977
1212c19:dd:d9:dd:c25:c25:94de:4978/1282c19:dd:d9:dd:c25:c25:94de:4978
1222c19:dd:d9:dd:c25:c25:94de:4979/1282c19:dd:d9:dd:c25:c25:94de:4979
1232c19:dd:d9:dd:c25:c25:94de:497a/1282c19:dd:d9:dd:c25:c25:94de:497a
1242c19:dd:d9:dd:c25:c25:94de:497b/1282c19:dd:d9:dd:c25:c25:94de:497b
1252c19:dd:d9:dd:c25:c25:94de:497c/1282c19:dd:d9:dd:c25:c25:94de:497c
1262c19:dd:d9:dd:c25:c25:94de:497d/1282c19:dd:d9:dd:c25:c25:94de:497d
1272c19:dd:d9:dd:c25:c25:94de:497e/1282c19:dd:d9:dd:c25:c25:94de:497e
1282c19:dd:d9:dd:c25:c25:94de:497f/1282c19:dd:d9:dd:c25:c25:94de:497f
1292c19:dd:d9:dd:c25:c25:94de:4980/1282c19:dd:d9:dd:c25:c25:94de:4980
1302c19:dd:d9:dd:c25:c25:94de:4981/1282c19:dd:d9:dd:c25:c25:94de:4981
1312c19:dd:d9:dd:c25:c25:94de:4982/1282c19:dd:d9:dd:c25:c25:94de:4982
1322c19:dd:d9:dd:c25:c25:94de:4983/1282c19:dd:d9:dd:c25:c25:94de:4983
1332c19:dd:d9:dd:c25:c25:94de:4984/1282c19:dd:d9:dd:c25:c25:94de:4984
1342c19:dd:d9:dd:c25:c25:94de:4985/1282c19:dd:d9:dd:c25:c25:94de:4985
1352c19:dd:d9:dd:c25:c25:94de:4986/1282c19:dd:d9:dd:c25:c25:94de:4986
1362c19:dd:d9:dd:c25:c25:94de:4987/1282c19:dd:d9:dd:c25:c25:94de:4987
1372c19:dd:d9:dd:c25:c25:94de:4988/1282c19:dd:d9:dd:c25:c25:94de:4988
1382c19:dd:d9:dd:c25:c25:94de:4989/1282c19:dd:d9:dd:c25:c25:94de:4989
1392c19:dd:d9:dd:c25:c25:94de:498a/1282c19:dd:d9:dd:c25:c25:94de:498a
1402c19:dd:d9:dd:c25:c25:94de:498b/1282c19:dd:d9:dd:c25:c25:94de:498b
1412c19:dd:d9:dd:c25:c25:94de:498c/1282c19:dd:d9:dd:c25:c25:94de:498c
1422c19:dd:d9:dd:c25:c25:94de:498d/1282c19:dd:d9:dd:c25:c25:94de:498d
1432c19:dd:d9:dd:c25:c25:94de:498e/1282c19:dd:d9:dd:c25:c25:94de:498e
1442c19:dd:d9:dd:c25:c25:94de:498f/1282c19:dd:d9:dd:c25:c25:94de:498f
1452c19:dd:d9:dd:c25:c25:94de:4990/1282c19:dd:d9:dd:c25:c25:94de:4990
1462c19:dd:d9:dd:c25:c25:94de:4991/1282c19:dd:d9:dd:c25:c25:94de:4991
1472c19:dd:d9:dd:c25:c25:94de:4992/1282c19:dd:d9:dd:c25:c25:94de:4992
1482c19:dd:d9:dd:c25:c25:94de:4993/1282c19:dd:d9:dd:c25:c25:94de:4993
1492c19:dd:d9:dd:c25:c25:94de:4994/1282c19:dd:d9:dd:c25:c25:94de:4994
1502c19:dd:d9:dd:c25:c25:94de:4995/1282c19:dd:d9:dd:c25:c25:94de:4995
1512c19:dd:d9:dd:c25:c25:94de:4996/1282c19:dd:d9:dd:c25:c25:94de:4996
1522c19:dd:d9:dd:c25:c25:94de:4997/1282c19:dd:d9:dd:c25:c25:94de:4997
1532c19:dd:d9:dd:c25:c25:94de:4998/1282c19:dd:d9:dd:c25:c25:94de:4998
1542c19:dd:d9:dd:c25:c25:94de:4999/1282c19:dd:d9:dd:c25:c25:94de:4999
1552c19:dd:d9:dd:c25:c25:94de:499a/1282c19:dd:d9:dd:c25:c25:94de:499a
1562c19:dd:d9:dd:c25:c25:94de:499b/1282c19:dd:d9:dd:c25:c25:94de:499b
1572c19:dd:d9:dd:c25:c25:94de:499c/1282c19:dd:d9:dd:c25:c25:94de:499c
1582c19:dd:d9:dd:c25:c25:94de:499d/1282c19:dd:d9:dd:c25:c25:94de:499d
1592c19:dd:d9:dd:c25:c25:94de:499e/1282c19:dd:d9:dd:c25:c25:94de:499e
1602c19:dd:d9:dd:c25:c25:94de:499f/1282c19:dd:d9:dd:c25:c25:94de:499f
1612c19:dd:d9:dd:c25:c25:94de:49a0/1282c19:dd:d9:dd:c25:c25:94de:49a0
1622c19:dd:d9:dd:c25:c25:94de:49a1/1282c19:dd:d9:dd:c25:c25:94de:49a1
1632c19:dd:d9:dd:c25:c25:94de:49a2/1282c19:dd:d9:dd:c25:c25:94de:49a2
1642c19:dd:d9:dd:c25:c25:94de:49a3/1282c19:dd:d9:dd:c25:c25:94de:49a3
1652c19:dd:d9:dd:c25:c25:94de:49a4/1282c19:dd:d9:dd:c25:c25:94de:49a4
1662c19:dd:d9:dd:c25:c25:94de:49a5/1282c19:dd:d9:dd:c25:c25:94de:49a5
1672c19:dd:d9:dd:c25:c25:94de:49a6/1282c19:dd:d9:dd:c25:c25:94de:49a6
1682c19:dd:d9:dd:c25:c25:94de:49a7/1282c19:dd:d9:dd:c25:c25:94de:49a7
1692c19:dd:d9:dd:c25:c25:94de:49a8/1282c19:dd:d9:dd:c25:c25:94de:49a8
1702c19:dd:d9:dd:c25:c25:94de:49a9/1282c19:dd:d9:dd:c25:c25:94de:49a9
1712c19:dd:d9:dd:c25:c25:94de:49aa/1282c19:dd:d9:dd:c25:c25:94de:49aa
1722c19:dd:d9:dd:c25:c25:94de:49ab/1282c19:dd:d9:dd:c25:c25:94de:49ab
1732c19:dd:d9:dd:c25:c25:94de:49ac/1282c19:dd:d9:dd:c25:c25:94de:49ac
1742c19:dd:d9:dd:c25:c25:94de:49ad/1282c19:dd:d9:dd:c25:c25:94de:49ad
1752c19:dd:d9:dd:c25:c25:94de:49ae/1282c19:dd:d9:dd:c25:c25:94de:49ae
1762c19:dd:d9:dd:c25:c25:94de:49af/1282c19:dd:d9:dd:c25:c25:94de:49af
1772c19:dd:d9:dd:c25:c25:94de:49b0/1282c19:dd:d9:dd:c25:c25:94de:49b0
1782c19:dd:d9:dd:c25:c25:94de:49b1/1282c19:dd:d9:dd:c25:c25:94de:49b1
1792c19:dd:d9:dd:c25:c25:94de:49b2/1282c19:dd:d9:dd:c25:c25:94de:49b2
1802c19:dd:d9:dd:c25:c25:94de:49b3/1282c19:dd:d9:dd:c25:c25:94de:49b3
1812c19:dd:d9:dd:c25:c25:94de:49b4/1282c19:dd:d9:dd:c25:c25:94de:49b4
1822c19:dd:d9:dd:c25:c25:94de:49b5/1282c19:dd:d9:dd:c25:c25:94de:49b5
1832c19:dd:d9:dd:c25:c25:94de:49b6/1282c19:dd:d9:dd:c25:c25:94de:49b6
1842c19:dd:d9:dd:c25:c25:94de:49b7/1282c19:dd:d9:dd:c25:c25:94de:49b7
1852c19:dd:d9:dd:c25:c25:94de:49b8/1282c19:dd:d9:dd:c25:c25:94de:49b8
1862c19:dd:d9:dd:c25:c25:94de:49b9/1282c19:dd:d9:dd:c25:c25:94de:49b9
1872c19:dd:d9:dd:c25:c25:94de:49ba/1282c19:dd:d9:dd:c25:c25:94de:49ba
1882c19:dd:d9:dd:c25:c25:94de:49bb/1282c19:dd:d9:dd:c25:c25:94de:49bb
1892c19:dd:d9:dd:c25:c25:94de:49bc/1282c19:dd:d9:dd:c25:c25:94de:49bc
1902c19:dd:d9:dd:c25:c25:94de:49bd/1282c19:dd:d9:dd:c25:c25:94de:49bd
1912c19:dd:d9:dd:c25:c25:94de:49be/1282c19:dd:d9:dd:c25:c25:94de:49be
1922c19:dd:d9:dd:c25:c25:94de:49bf/1282c19:dd:d9:dd:c25:c25:94de:49bf
1932c19:dd:d9:dd:c25:c25:94de:49c0/1282c19:dd:d9:dd:c25:c25:94de:49c0
1942c19:dd:d9:dd:c25:c25:94de:49c1/1282c19:dd:d9:dd:c25:c25:94de:49c1
1952c19:dd:d9:dd:c25:c25:94de:49c2/1282c19:dd:d9:dd:c25:c25:94de:49c2
1962c19:dd:d9:dd:c25:c25:94de:49c3/1282c19:dd:d9:dd:c25:c25:94de:49c3
1972c19:dd:d9:dd:c25:c25:94de:49c4/1282c19:dd:d9:dd:c25:c25:94de:49c4
1982c19:dd:d9:dd:c25:c25:94de:49c5/1282c19:dd:d9:dd:c25:c25:94de:49c5
1992c19:dd:d9:dd:c25:c25:94de:49c6/1282c19:dd:d9:dd:c25:c25:94de:49c6
2002c19:dd:d9:dd:c25:c25:94de:49c7/1282c19:dd:d9:dd:c25:c25:94de:49c7
2012c19:dd:d9:dd:c25:c25:94de:49c8/1282c19:dd:d9:dd:c25:c25:94de:49c8
2022c19:dd:d9:dd:c25:c25:94de:49c9/1282c19:dd:d9:dd:c25:c25:94de:49c9
2032c19:dd:d9:dd:c25:c25:94de:49ca/1282c19:dd:d9:dd:c25:c25:94de:49ca
2042c19:dd:d9:dd:c25:c25:94de:49cb/1282c19:dd:d9:dd:c25:c25:94de:49cb
2052c19:dd:d9:dd:c25:c25:94de:49cc/1282c19:dd:d9:dd:c25:c25:94de:49cc
2062c19:dd:d9:dd:c25:c25:94de:49cd/1282c19:dd:d9:dd:c25:c25:94de:49cd
2072c19:dd:d9:dd:c25:c25:94de:49ce/1282c19:dd:d9:dd:c25:c25:94de:49ce
2082c19:dd:d9:dd:c25:c25:94de:49cf/1282c19:dd:d9:dd:c25:c25:94de:49cf
2092c19:dd:d9:dd:c25:c25:94de:49d0/1282c19:dd:d9:dd:c25:c25:94de:49d0
2102c19:dd:d9:dd:c25:c25:94de:49d1/1282c19:dd:d9:dd:c25:c25:94de:49d1
2112c19:dd:d9:dd:c25:c25:94de:49d2/1282c19:dd:d9:dd:c25:c25:94de:49d2
2122c19:dd:d9:dd:c25:c25:94de:49d3/1282c19:dd:d9:dd:c25:c25:94de:49d3
2132c19:dd:d9:dd:c25:c25:94de:49d4/1282c19:dd:d9:dd:c25:c25:94de:49d4
2142c19:dd:d9:dd:c25:c25:94de:49d5/1282c19:dd:d9:dd:c25:c25:94de:49d5
2152c19:dd:d9:dd:c25:c25:94de:49d6/1282c19:dd:d9:dd:c25:c25:94de:49d6
2162c19:dd:d9:dd:c25:c25:94de:49d7/1282c19:dd:d9:dd:c25:c25:94de:49d7
2172c19:dd:d9:dd:c25:c25:94de:49d8/1282c19:dd:d9:dd:c25:c25:94de:49d8
2182c19:dd:d9:dd:c25:c25:94de:49d9/1282c19:dd:d9:dd:c25:c25:94de:49d9
2192c19:dd:d9:dd:c25:c25:94de:49da/1282c19:dd:d9:dd:c25:c25:94de:49da
2202c19:dd:d9:dd:c25:c25:94de:49db/1282c19:dd:d9:dd:c25:c25:94de:49db
2212c19:dd:d9:dd:c25:c25:94de:49dc/1282c19:dd:d9:dd:c25:c25:94de:49dc
2222c19:dd:d9:dd:c25:c25:94de:49dd/1282c19:dd:d9:dd:c25:c25:94de:49dd
2232c19:dd:d9:dd:c25:c25:94de:49de/1282c19:dd:d9:dd:c25:c25:94de:49de
2242c19:dd:d9:dd:c25:c25:94de:49df/1282c19:dd:d9:dd:c25:c25:94de:49df
2252c19:dd:d9:dd:c25:c25:94de:49e0/1282c19:dd:d9:dd:c25:c25:94de:49e0
2262c19:dd:d9:dd:c25:c25:94de:49e1/1282c19:dd:d9:dd:c25:c25:94de:49e1
2272c19:dd:d9:dd:c25:c25:94de:49e2/1282c19:dd:d9:dd:c25:c25:94de:49e2
2282c19:dd:d9:dd:c25:c25:94de:49e3/1282c19:dd:d9:dd:c25:c25:94de:49e3
2292c19:dd:d9:dd:c25:c25:94de:49e4/1282c19:dd:d9:dd:c25:c25:94de:49e4
2302c19:dd:d9:dd:c25:c25:94de:49e5/1282c19:dd:d9:dd:c25:c25:94de:49e5
2312c19:dd:d9:dd:c25:c25:94de:49e6/1282c19:dd:d9:dd:c25:c25:94de:49e6
2322c19:dd:d9:dd:c25:c25:94de:49e7/1282c19:dd:d9:dd:c25:c25:94de:49e7
2332c19:dd:d9:dd:c25:c25:94de:49e8/1282c19:dd:d9:dd:c25:c25:94de:49e8
2342c19:dd:d9:dd:c25:c25:94de:49e9/1282c19:dd:d9:dd:c25:c25:94de:49e9
2352c19:dd:d9:dd:c25:c25:94de:49ea/1282c19:dd:d9:dd:c25:c25:94de:49ea
2362c19:dd:d9:dd:c25:c25:94de:49eb/1282c19:dd:d9:dd:c25:c25:94de:49eb
2372c19:dd:d9:dd:c25:c25:94de:49ec/1282c19:dd:d9:dd:c25:c25:94de:49ec
2382c19:dd:d9:dd:c25:c25:94de:49ed/1282c19:dd:d9:dd:c25:c25:94de:49ed
2392c19:dd:d9:dd:c25:c25:94de:49ee/1282c19:dd:d9:dd:c25:c25:94de:49ee
2402c19:dd:d9:dd:c25:c25:94de:49ef/1282c19:dd:d9:dd:c25:c25:94de:49ef
2412c19:dd:d9:dd:c25:c25:94de:49f0/1282c19:dd:d9:dd:c25:c25:94de:49f0
2422c19:dd:d9:dd:c25:c25:94de:49f1/1282c19:dd:d9:dd:c25:c25:94de:49f1
2432c19:dd:d9:dd:c25:c25:94de:49f2/1282c19:dd:d9:dd:c25:c25:94de:49f2
2442c19:dd:d9:dd:c25:c25:94de:49f3/1282c19:dd:d9:dd:c25:c25:94de:49f3
2452c19:dd:d9:dd:c25:c25:94de:49f4/1282c19:dd:d9:dd:c25:c25:94de:49f4
2462c19:dd:d9:dd:c25:c25:94de:49f5/1282c19:dd:d9:dd:c25:c25:94de:49f5
2472c19:dd:d9:dd:c25:c25:94de:49f6/1282c19:dd:d9:dd:c25:c25:94de:49f6
2482c19:dd:d9:dd:c25:c25:94de:49f7/1282c19:dd:d9:dd:c25:c25:94de:49f7
2492c19:dd:d9:dd:c25:c25:94de:49f8/1282c19:dd:d9:dd:c25:c25:94de:49f8
2502c19:dd:d9:dd:c25:c25:94de:49f9/1282c19:dd:d9:dd:c25:c25:94de:49f9
2512c19:dd:d9:dd:c25:c25:94de:49fa/1282c19:dd:d9:dd:c25:c25:94de:49fa
2522c19:dd:d9:dd:c25:c25:94de:49fb/1282c19:dd:d9:dd:c25:c25:94de:49fb
2532c19:dd:d9:dd:c25:c25:94de:49fc/1282c19:dd:d9:dd:c25:c25:94de:49fc
2542c19:dd:d9:dd:c25:c25:94de:49fd/1282c19:dd:d9:dd:c25:c25:94de:49fd
2552c19:dd:d9:dd:c25:c25:94de:49fe/1282c19:dd:d9:dd:c25:c25:94de:49fe
2562c19:dd:d9:dd:c25:c25:94de:49ff/1282c19:dd:d9:dd:c25:c25:94de:49ff

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.