Online Drive that support Finding File Duplication and Comparison?

I have 5 USB Portable HDD, a old Desktop Drive, and many files on NAS. Some are overlapped as I move from one drive to another. I wanted to back everything into the Cloud. So I can have those HDD thrown away. But I also want to organise those files once and for all. Is there any online Drive that allow Finding File Duplication, by name, by hash and compare?