Write useful alt text for marketing images
Choose alt text from an image’s purpose, with practical examples for informative covers, linked controls, decorative images and charts.
Ask what the image contributes here
The same photograph can be informative in one context and decorative in another. Decide what a reader would miss if it were unavailable. That question produces more useful alt text than inserting the article’s keywords into every image.
W3C’s image decision tree distinguishes informative, functional, text-containing and decorative uses. The examples below apply those functions to original marketing-page scenarios; they do not establish full accessibility conformance by themselves. [W3C WAI: An alt Decision Tree]
Before-and-after examples by function
| Image and context | Weak alternative | More useful treatment |
|---|---|---|
| Macro cover illustrating measurement boundaries | Best analytics SEO marketing tools | A steel calibration weight on a dark surface |
| Image-only control opening a worksheet | Blue download arrow | Download the planning worksheet |
| Abstract divider with no information | Marketing growth background design | Empty alt when it is purely decorative |
| Chart carrying a revenue comparison | Revenue chart | Short chart purpose plus a nearby accessible table or equivalent detailed explanation |
| Logo link with no other label | Company logo image | Business name or destination purpose as appropriate |
The calibration-weight description states what is visibly present. It should not claim that the image proves measurement precision or contains a real campaign result. A generated editorial cover remains an illustration even when its material looks photographic.
If visible text beside a linked image already provides the accessible link name, avoid repeating an unnecessary long label. Evaluate the combined control, not each asset in isolation. For a control whose only label is the image, the alternative must communicate the action or destination.
Give charts and screenshots an equivalent answer
A complex chart needs more than a miniature transcription in an alt attribute. State the chart’s purpose briefly, then provide the important values, units, period and interpretation in nearby text or a properly structured table. The reader should be able to understand the conclusion without reading pixels.
For a screenshot of a configuration, explain the setting or diagnostic point in the article. Do not require someone to infer an entire procedure from a screenshot full of tiny interface labels. Redact personal values and secrets before publishing the image.
If an image contains a claim, verify that claim independently. Alt text should not make an unsupported guarantee simply because the visible asset uses one. A fabricated testimonial or invented conversion graph remains unsupported in both representations.
Review the final context, not only the file name
- Identify the image’s role in the final page.
- Read the surrounding heading, caption and link text.
- Write the shortest alternative that preserves the needed meaning.
- Use an empty alternative only when the decorative/redundant decision is justified.
- Check the actual rendered alt attribute and the accessible control name.
- Verify that mobile cropping has not changed the meaningful visual content.
Avoid keyword stuffing, filenames and repeated phrases such as “image of” where they add nothing. A meaningful technical term can be included when it describes the content, but a list of target queries is not an image description.
I would keep the cover’s object description separate from the article title and the search description. Those fields do different jobs. The result is easier to maintain when an image is replaced without rewriting the whole article.
Sources
AI-assisted writing and an AI-generated editorial cover. Source links and checked dates are listed below; illustrative examples are labeled in the text.
- W3C WAI: An alt Decision Tree — checked 2026-10-18