FastStone Photo Resizer - Convert and Rename images in batch mode Support JPEG, BMP, GIF, PNG, TIFF and JPEG2000
Batch Image Resizer - Resize, crop, shrink, flip, exif-rotate, convert, enhance, process multiple pictures and photos with professional software! 120+ Actions, 30+ Image Formats
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.
Bulk Resize Photos - Resize large photos in bulk
IrfanView - IrfanView ... one of the most popular viewers worldwide.
Compress JPG Online - Online image compression tool to reduce the file size of JPG images.