Image SEO: Alt Text, File Names and Page Speed
Practical image optimization: descriptive file names, useful alt text, modern formats, and compressed files that please Google and visitors.
Images affect rankings through accessibility, image-search traffic, and page speed. Three habits cover most of the benefit: name files well, write honest alt text, and compress aggressively.
File Names and Alt Text
Upload photos as short-earnings-chart.jpg instead of IMG_2048.jpg, and write alt text describing what the image shows for visually impaired users — including the topic naturally when it genuinely fits. Never stuff keywords; screen-reader users deserve honest descriptions.
Formats and Compression
Serve WebP or AVIF where supported, size images to their display dimensions, and enable lazy loading below the fold. A hero image larger than your entire page’s HTML is the most common speed killer on content sites.
Structured Options
Descriptive captions and image sitemaps help image-search discovery. Original images also attract backlinks when others cite your charts — an underrated link source.
Frequently Asked Questions
Does alt text help rankings?
Primarily accessibility and image search — both of which bring real users.
How big should a web image be?
Under 100 KB for typical inline images; hero images under 200 KB with modern formats.
Do I need an image sitemap?
Not usually — good captions and alt text suffice for most content sites.
Rename and re-compress the five heaviest images on your fastest-growing post — measure the speed difference immediately.