How to write alt text for AI-generated images

You made a picture, it is exactly right, and now the page editor asks for "alt text". Most people type the file name, paste the prompt, or skip the box. All three waste the field. Alt text is a few words that stand in for the picture when it cannot be seen: for a screen reader user, for a visitor on a slow connection, for a search engine reading the page. This is a short, practical way to write it for pictures you generated yourself.

What alt text is actually for

It has one job: give the reader what the picture gives a sighted visitor, in the place where the picture sits. It is not a caption (a caption is visible to everyone and adds context), and it is not a keyword box. Search engines do read it, and a clear honest description helps them understand the page, but a sentence stuffed with search terms helps nobody, and screen reader users notice at once.

A simple formula

Ask three questions, in this order, and write one plain sentence from the answers.

1. 01What is it? The main subject, in everyday words: a ceramic mug, a lighthouse, a bar chart.
2. 02What matters about it here? The detail the page needs: the colour of the product, the mood of the cover, the trend of the chart.
3. 03What kind of picture is it? Only when it changes the meaning: illustration, 3D render, photo-style render, watercolour.

Keep it to roughly one sentence. Skip "image of" and "picture of": the screen reader already announces that it is an image.

Informative or decorative: decide first

Before writing anything, ask whether the picture carries information the text next to it does not. A product shot on a product page does. A calm abstract background behind a heading does not. A decorative picture should get an empty alt attribute (alt=""), which tells assistive tools to skip it. That is better than a description that makes someone listen to "purple gradient with soft light" three times a page.

• Informative: product shots, illustrations that explain something, charts, the cover of an article. Describe them.
• Decorative: textures, dividers, mood backgrounds, a header image that only repeats the title. Leave the alt empty.
• Functional: a picture inside a link or button. Describe where it goes or what it does, not how it looks.

Describe the style honestly

A generated picture is not a photograph of a real place, and alt text should not pretend it is. If the style matters to the reader, say what it is: "Illustration of a lighthouse on a cliff at dusk" or "Rendered product image of a ceramic mug on an oak table". Do not write "photo of" for something that was never photographed. The point is not to advertise the tool, it is to avoid misleading the person who cannot check for themselves. If you publish generated images, the guide to telling AI images apart covers the other side of that honesty.

Three examples

A product shot

On a shop page the reader needs what a customer would see: colour, shape, the setting only if it matters.

An illustration

For a blog cover that sets the mood, one short sentence is enough, and an empty alt is fine if the title already says it.

A chart-like image

Here the picture carries data, so the alt must carry the message. Be careful: image models draw things that look like charts, but their numbers and labels are not reliable (the hands and text guide explains why). Build a real chart in a chart tool, and write the alt from its real data. Put the full figures in a table or in the text next to it.

Use your prompt as a draft, not a copy

The prompt you wrote is a useful first draft, because it already names the subject. Do not paste it, though. A good prompt is a recipe for the model: it carries lighting terms, camera words and style tags that mean nothing to a listener (the prompt guide covers why they help the model). And a prompt describes what you wanted, while alt text must describe what is actually in the finished picture. Models drift: the third mug may have no handle. Look at the result, then keep the subject from your prompt, drop the technical words, and fix anything that did not come out as asked.

A quick checklist

• Is the picture informative, decorative or functional?
• One sentence, subject first, no "image of".
• The detail this page needs, not every detail.
• The kind of picture named when it matters (illustration, render).
• Matches the final image, not just the prompt.
• No keyword lists, no file names.

What the studio does and does not do

The studio makes the picture; it does not write alt text for you and it does not add it to your downloads. The picture arrives at 2K and the description is yours to write where you publish it, which is where the page context is known. That is your call: only you know what the picture is for. For product and cover work, the product photography and blog header posts show the images this advice applies to. Open the studio to make them, or see the models page for the styles on offer.