- The file size of the image should be around 100KB. Images over 200KB may slow site loading time significantly.
- To ensure the image also looks good on a phone, make sure that the middle of the image has relevant visual elements that look good in the event that the image is cropped vertically for the phone view.
KEEP THE IMAGE SIZE SMALL
The best thing about choosing images for the site, is that they tend to bring in more traffic. However, increasing traffic requires the right kind of optimization for images. An important thing in choosing images is keeping them relevant to the topic of the page, so the user experience does not suffer.“Large images slow down the loading time of the site”
Choosing high quality images is also important, and so is keeping them small. Images on the site should always be compressed to be as small as possible while keeping them sharp and high quality. Low quality images weaken the user experience.
Large images increase loading times, which directly impacts the site's ranking in search results. If the images force the site's loading time above 10 seconds, you can kiss your potential customers goodbye. Amazon conducted a study where it was found that if a specific site's loading time increased by one second, the company lost $1.6 billion over the year. The size of the image should be around 100KB. Images sized over 200KB may slow site loading time significantly.
A good tool for resizing images is JPEGmini. And you can always use the trusty Paint-program to downsize your images by clicking Home → Image → Resize.