Why It Matters

Alt text ensures compliance with Web Content Accessibility Guidelines (WCAG) by allowing visually impaired users relying on screen readers to understand document imagery. Additionally, alt text allows search engines to index images in Google Images and comprehend image context relative to surrounding text.

Key Best Practices & Guidelines

  • Be Specific & Contextual: Describe the visual details and purpose of the image (e.g., alt="Bar chart showing 35% organic traffic growth after SEO audit" instead of alt="chart").

  • Maintain Concise Length: Aim for about 125 characters or fewer. Modern screen readers read the whole description, but short, specific alt text is easier to listen to; put longer explanations (such as the data in a chart) in a caption or the surrounding text.

  • Empty Alt for Decorative Imagery: Use empty null alt attributes (alt="") for purely aesthetic background images or icons so screen readers skip them quietly.

  • Omit Redundant Lead-Ins: Never start alt text with redundant phrases like "Image of" or "Photo of", as screen readers already announce the presence of an image element.