Image alt text, also known as “alternative text” or “alt attributes,” refers to the descriptive text added to an image’s HTML tag on a webpage. It is intended to provide context and convey the content and function of the image to search engine crawlers and to assistive technologies used by individuals who are visually impaired.
Importance in SEO:
Alt text plays a crucial role in search engine optimization (SEO) as it helps search engines understand the content and context of images, which can be indexed and returned in image search results. Properly optimized alt text can contribute to a website’s relevance and accessibility, potentially improving its search engine rankings.
Best Practices:
- Ensure that the alt text is descriptive and accurately reflects the subject matter of the image.
- Keep the alt attribute concise, generally under 125 characters, allowing screen readers to process the content effectively.
- Include relevant keywords that pertain to the image and the content of the page but avoid keyword stuffing.
- Do not use phrases like image of or picture of as screen readers already announce the image presence.
- For purely decorative images that hold no informational value, alt text can be left empty (alt=””) to prevent screen readers from focusing on them.
- Alt text should also conform to the page content and the context in which the image is used.
Accessibility Benefits:
Beyond SEO, alt text is central to web accessibility, making visual content usable for individuals using screen readers or when images fail to load. It highlights the importance of creating a web experience that is inclusive and optimized for all users, in line with best practices and web accessibility guidelines such as the Web Content Accessibility Guidelines (WCAG).