The minimum billable size for Object Storage Service (OSS) Infrequent Access (IA) and Archive objects is 64 KB. Objects smaller than 64 KB are charged as 64 KB. Therefore, if a bucket contains a large number of IA or Archive objects smaller than 64 KB, the billed storage usage may be greater than the actual storage usage.
You can view the actual storage usage and billed storage usage of IA and Archive objects on the Overview page of the bucket in the OSS console. For more information, see Bucket overview.