Alt Text vs Image Descriptions: The Clear Guide for Real Results

byTheAmazingMG

1.6K followers

3 months ago

Laptop on a minimalist desk, showing a media upload

Key Takeaways:

Alt text = short, functional, invisible.

Image description = detailed, human, visible.

Both improve accessibility and SEO when used right.

Don’t keyword-stuff. Keep it natural and valuable.

Write for people first, algorithms second.

Alt Text vs Image Descriptions

When discussing image SEO, people often use snazzy terms like alt text and image descriptions.
But most site owners still mix them up.

Let’s fix that. I’ll show you what each one does, how to write them right, and how to use them to rank higher and make your site more accessible.

What Alt Text Really Does

Alt text (short for “alternative text”) describes an image in code.
Screen readers read it aloud when someone can’t see the image.
Search engines also read it to understand what’s shown.

Think of alt text as the image’s backup voice.

Why It Matters

• Accessibility: It lets people with vision loss understand your content.
• SEO: It helps Google index your images correctly.
• User experience: It shows text if an image fails to load.

How to Write Alt Text That Works

• Keep it under 125 characters.
• Describe what’s important, not every pixel in the image.
• Write like you’re explaining the image to a friend.
• Add a keyword only if it fits naturally.

Bad example:
alt="SEO image alt text best practice guide for optimization keyword ranking using jogging image"

Good example:
alt="Person jogging in a park during sunrise"

That’s clear, short, and readable for both humans and the Google bots!

What Image Descriptions Do

Image descriptions give more context than alt text.
They’re written for humans, not for screen readers.
You usually see them as captions or nearby text.

Example:

A man jogs through a quiet park as sunlight cuts through the trees. It’s a peaceful start to the day.

That line provides emotion and context, which alt text should avoid.

Why It Matters

• It makes your content feel richer and more complete.
• It keeps readers on the page longer (a ranking signal).
• It adds crawlable text that supports your topic.

The Simple Difference

Both matter, but for different reasons.
Alt text helps Google understand the image.
Image descriptions help get a grasp of what your image is about.

How to Use Both in WordPress

1. Add Alt Text in Media Library:
2. • Go to Media ➡️ Library
   • Click your image
   • Fill in the Alt Text box (keep it simple)
2. Add a Description or Caption:
3. • Use the caption field or write it under the image.
   • Add details that give context or tell a story.
3. Test Your Work:
4. • Use tools like Lighthouse or SiteImprove to check accessibility.
   • Use Google Search Console ➡️ Image Search to track indexed visuals.

Writing Tips That Google and Users Love

Infographic showing blog traffic growth” beats “chart with green bars."

• Describe intent, not just looks.
• An Infographic showing “blog traffic growth” beats “chart with green bars.”
• Don’t repeat text that’s already nearby.
• Mention your keyword once if it fits.
• You can even test how your images sound through a screen reader.

Example Workflow I Use

When I upload a new blog image:

1. Add short alt text in WordPress.
2. Write a caption that adds personality.
3. Compress it with TinyPNG or Kracken.
4. Recheck it in Search Console after indexing.

This simple process keeps my images fast, findable, and accessible.

Ready to fix your site’s images?
Go through ten of your posts today and rewrite the alt text using this guide.
You’ll help your readers, and you’ll help Google help you.