Understanding the Importance of Alt Attributes

What is the alt and why does it matter?

The alt attribute (for alternative text ) describes the content of an image in the HTML code:

If there's a display issue, this text appears in place of the image. Crucially, it's read by assistive technologies (screen readers) and serves as a semantic signal for search engines. When well-written, it improves accessibility, user experience, and SEO.

Accessibility: giving meaning to images

• Screen readers : alt text is the spoken description of an image. Without it, the user perceives a meaningless “image…”

• Content understanding : a good alt text places the image in the editorial context, not in an absolute sense.

• Navigation : it avoids dead ends (especially for image links or button icons).

When to use alt="" (empty)

• Decorative images that provide no information (features, backgrounds, patterns):

  <img src="ornament.svg" alt="" aria-hidden="true">


  They are silenced so as not to interfere with the reading experience.

SEO: a relevant signal, but one to be handled with care

Search engines don't "see" pixels; they interpret what you declare. A alt text :

• Provides context to the page and image (useful for Google Images).

• It improves overall relevance if it naturally incorporates the terms of the topic.

• Avoid keyword stuffing : stay natural, specific, concise.

Good writing practices

1. Describe what the image shows + the intention on the page.
   Bad: alt="image of a shoe"
   Good: alt="Black leather pointed-toe pumps, Winter 2025 collection"

2. Be concise : aim for 5 to 15 words (or ~80–140 characters if necessary).

3. Avoid unnecessary prefixes : no “photo of”, “image of”, “visual of” (the screen reader already announces that it is an image).

4. Adapt to the role of the image :

   • Functional (image-link/button): describe the action, not the image.

     <a href="/cart">img <" src = " cart.svg alt = " View cart " > a >




   • Logo : use the name of the organization.

     <img src="logo.svg" alt="Maison Dupont">


   • Infographic/graphic : alt text + caption or detailed description nearby (<figcaption>(link “Learn more”).

     <figure>img <src = "sales-2024.png" alt = " DetailedSales Trends 2020–2024, Upward Trend" > <figcaption> figures in the table below . >





5. Language and precision : use the language of the page, clear terms, avoid unnecessary jargon.

6. Images containing text : if the text is essential (e.g., poster), include it in the alt text or, better yet, in the accessible caption.

Frequent special cases

• Decorative icons in buttons with pre-existing text :

  <button>
<img src="download.svg" alt="" aria-hidden="true"> Download the guide
button>


• SVG inline : prefer <title> pour l’accessibilité, et role="img" si nécessaire.

• Variable product images : dynamically generate a alt : “Silk midi dress, midnight blue, size 38”.

Common mistakes to avoid

• Forgetting the attribute : it's an accessibility flaw and a missed SEO opportunity.

• Vague descriptions : “image”, “photo”, “banner”.

• Text that is too long or marketing (“the best on the market, incredible…”): stick to the facts.

• Keyword stuffing : “luxury bag, luxury women’s bag, luxury leather bag” hinders comprehension.

Concrete examples

• Good practice

  <img src="plage-coucher-soleil.jpg"
alt="Sunset on a sandy beach with palm trees">


• Bad practice

  <img src="plage.jpg" alt="Beach Image">


• Image link

  <a href="/lookbook-ete">img <src = " vignette-lookbook.jpg" alt = " Open the summer lookbook " > a >




Editorial integration and process

• Checklist in the CMS : alt , contextual help with examples.

• Team training : designers, writers, integrators—everyone must know the “describe the intent” rule.

• Regular audit : accessibility/SEO tools to identify images without alt or irrelevant alt

• Governance : define who writes, who reviews, and at what time (e.g., during pre-publication QA).

Mini check-up in 7 questions

1. Is the image informative or purely decorative?

2. the alt text describe what is useful in the context of the page?

3. Is it concise, natural, without an “image of / photo of”?

4. For an image link, does the alt text describe theaction ?

5. For a graph, have I added a legend or a link to the data ?

6. Are the language, spelling, and terminology correct?

7. alt text prevent keyword stuffing ?

Key points to remember

The alt is a small detail with a big impact: it opens up your content to people who cannot see images, it clarifies your message for search engines, and it enhances the overall quality of your site.

Adopt a simple approach: describe the intent, remain concise, distinguish between informative and decorative images, and establish an audit process. Your accessibility improves, your SEO benefits, and your user experience becomes clearer.

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