Duplicate files · Duplicates basics
Will it find downloads saved twice, like "file (1).pdf"?
Short answer: Yes, if they're exact copies of at least 1 MB (or Include small files is on). Downloads is checked, and when another copy is filed in a working folder like Documents, Storage Studio recommends keeping that one and removing the Downloads copy.
Yes, as long as the two downloads are exact copies and at least 1 MB (or you've turned on Include small files). Downloads is one of the folders the This Mac source checks, and repeat downloads are one of the most common kinds of duplicate.
When one copy is in Downloads or on the Desktop and another has been filed in a working folder such as Documents, Storage Studio recommends keeping the filed copy and removing the one in Downloads.