I save them as .jpg
Over the decades...I've learned to reduce/change images with large resolutions to approx 800x600 (many phone or camera images are like 2500x3000 or larger). Most times I just change the first dimension to "800" and let the image resizer do its thing.
Like stated above...it prevents having images so large that you have to scroll left/right & up/down just to get some perspective of what you're looking at.
