ThumbsUp is a helpful tool that enables Mac users to transform their favorite pictures into thumbnails suitable for being uploaded onto webpages. The application lets you choose from various output formats, supports batch processing, and offers the results you need in minimum time.
This program doesn't provide you with a main window as all the output settings can be found in the Preferences menu. All you need to do is drag-and-drop the input files onto the app's icon (located on the Dock), and the tool automatically processes the images.
I like the fact that you can choose the proper naming pattern (with prefix or suffix) for the output files. This feature comes in handy when you wish to avoid overwriting situations, as the program saves the thumbnails into the same directory as the input images. The only disadvantage I could find during my testing was the fact that the application doesn't offer you an option to choose the destination folder for the output files. Instead, as I already mentioned, it saves the created thumbnails in the same folder with the input files.
However, ThumbsUp provides you with quality results within seconds, works with various input formats (images, PDFs, QuickTime movies, etc.), and delivers the output files you need with just a few clicks. Furthermore, the app doesn't come with a price tag.