What Is Alt Text? Describing Images Properly
DICTIONARY · SEO

What Is Alt Text?

Alt text is a written description of an image, used by screen readers, shown when an image fails to load, and read by search engines.

In plain English

Its primary purpose is accessibility. Someone using a screen reader hears the alt text in place of the image, so it should convey what the image communicates.

It is also how search engines understand an image, which is why accurate description and image SEO turn out to be the same task.

What to know

Describe the content
What the image shows, in the context of the page.
Keep it short
A sentence. Detail beyond that belongs in a caption.
Empty when decorative
A purely decorative image takes an empty alt attribute so it is skipped.
Never keyword-stuff
A list of keywords is useless to a listener and to a search engine.

Why it matters

Alt text is one of the few places where accessibility and SEO are the same work. Doing it properly serves people who cannot see the image and makes the image discoverable, and doing it badly fails both.

Common mistakes

×Leaving alt text empty on images that carry meaning.
×Stuffing keywords instead of describing the image.
×Describing the file rather than the content.
×Omitting the attribute entirely rather than setting it empty for decoration.

FAQs

Should every image have alt text?

Every image needs an alt attribute. Decorative ones should have it empty.

How long should it be?

One clear sentence. Longer descriptions belong in a caption or nearby text.

WRITTEN BY TARIQ SALLAM
Marketing Consultant. Entrepreneur. Content Creator.

I'm a marketing consultant, entrepreneur and content creator. I help businesses grow through practical marketing, websites, SEO, content and AI.

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