What is ALT text and why is it important?

ALT text (alternative text) is the text description that displays when an image can't be shown-whether blocked by the email client, failed to load, or being read by a screen reader. It's specified in the alt attribute: <img alt="Description here">

Why it matters: Accessibility-screen readers announce alt text to visually impaired users. Image blocking-many clients block images by default; alt text communicates content until images load. Failed loads-broken images show alt text instead of broken image icons.

Alt text is content, not decoration. Write alt text that conveys the image's purpose, not just its appearance. For a product photo: "Red running shoes, $89" not "image of shoes." For decorative images, use empty alt (alt="") so screen readers skip them. Good alt text makes your email functional for everyone in every condition.