FastStone Photo Resizer - Convert and Rename images in batch mode Support JPEG, BMP, GIF, PNG, TIFF and JPEG2000
DVDVideoSoft Image Convert and Resize - Free Image Convert and Resize is a compact yet powerful program for batch mode image processing.
ImBatch - ImBatch is a batch image processor with a nice graphical user interface.
Caesium Image Compressor - Compress your pictures up to 90% without visible quality loss.
XnConvert - XnConvert is an easy image converter for graphic files, photos and images available on Windows...
PhotoBulk - PhotoBulk is a bulk image editor for Mac that was created for the best experience of batch editing. With this image editing software for macOS you can add watermarks, optimize and resize pictures, convert images or rename photos in bulk.