Alt Text
Alt text (alternative text) is a written description added to an image's HTML code that describes the image's content and function for screen readers and search engines.
Alt text serves two critical purposes: web accessibility and SEO. For visually impaired users who rely on screen readers, alt text provides a verbal description of images they cannot see. For search engines that cannot "see" images either, alt text explains what an image depicts, helping it appear in image search results.
Decorative images that don't convey information can have empty alt attributes (alt="") so screen readers skip them. Alt text is also what displays when an image fails to load, giving users context about what they're missing. This fallback function makes it important for user experience even beyond accessibility and SEO.
In practice
- A food blog added descriptive alt text to 500 recipe photos and saw Google Images traffic increase by 40% within two months
- An e-commerce store wrote unique alt text for 2,000 product images instead of using file names, leading to a 15% increase in organic product page visits
- A real estate agency described each property photo with location, features, and room type, capturing searches like 'modern kitchen in Austin TX'
- A nonprofit improved their website's WCAG compliance score from 62% to 94% simply by adding proper alt text to all images
Not sure how this applies to you?
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