Image optimization is a method that involves formatting and delivering images in a way that minimizes the overall file size without sacrificing the image’s visual quality. It is an important aspect of Search Engine Optimization (SEO).
SEO is all about optimizing web content to appear higher in search engine rankings, leading to increased website traffic. When we talk about content, it’s not just text but also images, videos, infographics, etc. Properly optimized images can improve your website ranking and enhance the user experience significantly.
The primary process of image optimization for SEO involves choosing the right file format (JPEG, PNG, Gif, BMP etc.), name your images descriptively and in plain language, resizing your images (the size of your images can significantly impact your website’s speed), optimizing your alt attributes carefully, choosing your image dimensions and product angles wisely, reducing the file size for faster loading (using tools like Adobe Photoshop, TinyPNG), and leveraging browser caching.
Let’s consider examples of image optimization:
1. Properly naming an image: Instead of keeping the default file name (like “IMG001.jpeg”), name them descriptively. For example, if you own a bakery and you’re uploading pictures of a cake, use a descriptive name like “Chocolate_Cherry_Cake.jpeg” – this tells search engines exactly what the image is.
1. Using Alt Text: Alt text or alternative text is an attribute added to an image tag in HTML. For example, if your image doesn’t load, the alt text would appear instead. It’s another way to indicate to search engines what the image shows. An example of an alt attribute would be 
1. Image file size: High-resolution images are large files, and large files slow down your web page. So, ideally using photo compression tools can help reduce the image file size without a noticeable change in quality.
These practices intrigued Google’s interest as Google’s search algorithm takes into account page loading speed and user experience. Google Images also account for a significant amount of search traffic on the internet. So, properly optimized images can also result in better rankings in Google Images search, leading to additional traffic.
Sources:
1. “Choose the right image format” – Google Web Fundamentals (https://developers.google.com/web/fundamentals/performance/optimizing-content-efficiency/image-optimization)
2. “10 Must Know Image Optimization Tips” – Shopify Blog (https://www.shopify.com/blog/7412852-10-must-know-image-optimization-tips)
3. “Image SEO: Optimizing images for search engines” – Yoast SEO Blog (https://yoast.com/image-seo/)
4. “Optimize Images” – Google PageSpeed Insights (https://developers.google.com/speed/docs/insights/OptimizeImages)
