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What Is Alt Text?
Accessibility
Quick Answer
Alt text (alternative text) is a short written description added to an image's code, read aloud by screen readers for visually impaired visitors and displayed if the image fails to load — and also read by Google, since search engines can't "see" images directly.
Alt Text vs. Image Caption — What's the Difference?
| Alt Text | Caption | |
|---|---|---|
| Visible to sighted visitors | No | Yes |
| Purpose | Accessibility + SEO | Context for the reader |
Why Does Alt Text Matter for a Small Business?
- It's required for basic website accessibility — visually impaired visitors rely on it to understand your images.
- It gives Google Image Search something to index, which can be a source of additional traffic.
How Do You Write Good Alt Text?
- Describe what's actually in the image, specifically — not "image123" or "photo."
- Keep it concise, typically under 125 characters.
- Don't keyword-stuff it — describe the image, don't just repeat your target keyword.
Key Takeaways
- Alt text serves screen readers, failed image loads, and Google Image Search.
- It should describe the image specifically and concisely.
- It's an accessibility requirement first, an SEO bonus second.
How NetNav Helps
NetNav flags images across your site that are missing alt text.
Frequently Asked Questions
Does every image need alt text?
Yes, functionally — purely decorative images can have empty alt text, but anything conveying real information needs a description.
Does alt text help SEO?
Modestly — it's one of many small signals, and it's more valuable for accessibility than as a major ranking factor on its own.
Where do I add alt text?
Most website platforms have a dedicated alt text field directly in the image upload or edit settings.