Alt Text

Alt Text (Alternative Text) is a textual description of an image, graphic, or other non-text content used to improve accessibility for users who are visually impaired or using screen readers. Alt text conveys the meaning or purpose of the image, ensuring that the content is understandable even without seeing the visual. It is also used by search engines to index and categorize images.

Missing alt text is one of the most common accessibility failures on the web, and it also hurts SEO since Google can't read images. For product teams, it's a quick win — a one-line change per image that makes your product more inclusive and more discoverable. It also matters in B2B contexts where enterprise buyers run accessibility audits before approving software purchases.

GitHub's UI uses descriptive alt text on all status icons and avatars — so a screen reader user hears 'Pull request merged by @username' instead of just an unlabeled image.