Describe what matters
Write a short, specific description that communicates the image's meaning in its surrounding content. “Red hiking backpack beside a trail map ” is more useful than “image ” or ’ backpack photo. ”
Use context, not keyword stuffing
Alt text is not a place to list search terms. Include a keyword only when it accurately describes the image and helps explain the page. Repeating a phrase can make the text awkward for screen-reader users and does not create useful relevance.
Match the image's role
- Product: name the product and an important visible feature.
- Editorial: describe the event, people or action relevant to the story.
- Chart: summarize the takeaway, and provide the full data in nearby text.
- Link image: describe the destination or action.
- Decorative image: use an empty alt attribute, `alt=""`, so assistive technology skips it.
Keep it concise: aim for one natural sentence. Do not start with “image of ’ or “picture of ” the assistive technology already identifies it as an image.
Alt text and captions are different
A caption is visible to everyone and can add attribution or editorial detail. Alt text is an equivalent for the image when it is unavailable. They can overlap, but they should not blindly repeat each other.
Examples
Weak: “ SEO image optimization best image alt text website marketing.”
Better: “Editor reviewing descriptive alt text for a product photograph.”
Before publishing, check that every meaningful image has an intentional `alt` value. The OptmizeImage analyzer can suggest a starting filename and alt text after you load an image, but human context makes the final wording better.
Open the image toolkit →