GIPHY Create - Create animated GIFs from videos (by Giphy)
Bulk Resize Photos - Resize large photos in bulk
Instagiffer - Create GIFs from anything!
Bulk Image Resizer by RedKetchup - Resize, convert, or compress multiple images quickly. Compress PNG, JPEG, WEBP, or HEIC images in batch. Convert multiple images to the PNG, JPEG, WEBP, HEIC, GIF, ICO, TIFF, or BMP formats.
Giffing Tool - Giffing Tool is simply put: The fastest creator of high quality captioned GIFs available.
GIF Resizer - Create animated GIFs and resize GIFs too big to tweet!