How to do SEO for images

Image SEO starts with technical optimization and extends through file management, metadata, and contextual relevance. The most immediate action is reducing file size without sacrificing quality—large images slow page load times, which Google factors into rankings. Use compression tools like TinyPNG or ImageOptim, and serve images in modern formats like WebP instead of older JPG or PNG formats. For your clients' websites, implement lazy loading so images only load when users scroll near them, improving initial page speed metrics that directly impact search visibility.

Filename and alt text are where most agencies see quick wins with image SEO. Instead of generic filenames like "IMG_2849.jpg," use descriptive, keyword-relevant names such as "blue-ceramic-coffee-mugs-handmade.jpg." Alt text serves two purposes: it helps Google understand image content for indexing, and it provides accessibility for screen readers. Write alt text that describes what's in the image and naturally includes relevant keywords where appropriate—don't stuff keywords artificially. For a product photo, instead of "mug," write "handmade blue ceramic coffee mug with handle." This matters because Google increasingly indexes images separately and can rank them in image search results, which drives referral traffic for many e-commerce and visual content clients.

Structural markup amplifies image SEO by telling Google more context. Use schema.org markup, particularly Product schema for e-commerce sites or Article schema for images within blog content. This helps Google understand whether an image is a product photo, a diagram, or illustrative content, which improves how it's indexed and displayed. Additionally, place images strategically within content—images that appear near relevant text get more contextual weight. For clients in visual industries like design, fashion, or food, optimize the page containing the image for that topic. An image of a wedding dress performs better in image search when it's on a page optimized for "bohemian wedding dresses" rather than a generic page.

Don't overlook image sitemaps for sites with heavy visual content. Submit an image sitemap through Google Search Console so Google crawls and indexes all images, especially important for e-commerce sites with hundreds of product photos. Finally, ensure images are responsive and display properly on mobile devices—Google prioritizes mobile-first indexing, so images must scale appropriately across devices. These fundamentals combined create a comprehensive image SEO strategy that drives visibility in both regular search results and Google Images.