If you are looking for the best tool to view, convert, and read OST files without Outlook on Mac then you must use MacSonik OST Viewer Tool. This software is capable of exporting and saving OST files into PDF, DOC, MBOX, and other file formats. With the help of this tool, you can export OST email ranges between specific dates. The users only have to select a start and an end date for the files/folders, and the tool will start converting files into the selected format.