What a good image description includes
A useful description answers the questions a reader would ask if they couldn’t see the picture: what is the main subject, where is it, what is happening, and what does it look and feel like. The describer covers the subject and setting first, then composition, lighting, colours, style and mood, in plain prose without jargon or tags.
Because it only describes what is visible, the result stays factual. It won’t guess names of real people or invent details that aren’t in the image, which matters when descriptions are used publicly.
Turning a description into alt text
Alt text helps people who use screen readers and helps search engines understand your images. Good alt text is shorter than a full description: usually one sentence that captures what matters in the context of your page. Use the generated description as raw material, then keep the details your readers need.
For a product photo, that might be colour, material and angle. For an illustration in an article, it’s the idea the image supports. Leave out phrases such as “image of”, because screen readers already announce that it’s an image. Decorative images that add no information can have empty alt text instead.
Other ways people use it
Photographers use descriptions to tag and search large archives. Online sellers use them as a first draft for listings. Writers and teachers use them to explain artworks and diagrams, and designers use them to brief colleagues on a reference without sending a dozen screenshots.
Descriptions are available in 14 languages, which is handy when you publish the same catalogue or article in more than one language.
From description to AI prompt
The same description is also a solid general-purpose prompt for most image generators. When you want a prompt formatted for a specific model, pick it in the tool, for example Midjourney or Stable Diffusion, and the description is rewritten in that model’s style.
Checking a description before you publish
AI descriptions are a strong first draft, but a quick human check is worth it. Make sure colours, counts and any text in the image are right, and add context the picture can’t show, such as a product name, a place or the reason the image appears on your page. If an image contains a chart or diagram, add the key numbers or conclusion yourself. Remove details that don’t matter to your readers; a precise short description beats a long, generic one.
Guides from our blog
- How to reverse-engineer any image into a prompt, and when it works
A practical reverse prompting workflow: describe an image, format it for your generator, and refine one element at a time. What works, and what never will.