How Alt Text Helps with On-Page SEO
Alt text, or “alternative text,” is a short description added to an image in HTML. Its main purpose is to describe the image for screen readers and users who can't view it. But it also plays an important role in On-Page SEO.
Adding meaningful alt text to your images improves your website’s accessibility and helps Google understand your content better, which can positively influence your rankings.
🧠 What Is Alt Text?
Alt text is an attribute in an <img>
tag that describes what the image is about. Example:
If the image doesn’t load, the alt text is displayed in its place. It also helps search engines read and interpret images correctly.
🔍 Why Alt Text Matters for SEO
1. Improves Image SEO
Search engines can't "see" images like humans do. Alt text gives them context. This makes your images more likely to appear in Google Image Search, increasing visibility.
2. Enhances Accessibility
Alt text is read aloud by screen readers for visually impaired users. Accessible websites perform better in SEO and are compliant with global web standards.
3. Supports Keyword Strategy
Using relevant keywords in your alt text helps improve the page’s overall keyword relevance — but avoid keyword stuffing.
4. Boosts Page Relevance
Alt text contributes to the theme and subject of the page. If your images are aligned with the page topic and described correctly, Google better understands your page content.
✅ Best Practices for Writing Alt Text
Be Descriptive but Concise
Good:"Woman holding a phone showing Google Analytics report"
Bad:"image123"
or"SEO"
Use Keywords Naturally
Include a primary keyword if it fits the image naturally — don't force it.Avoid Keyword Stuffing
Google may penalize over-optimized or spammy alt text. Keep it readable.Don’t Use “Image of…” or “Picture of…”
It's unnecessary. Just describe the image directly.Apply Alt Text to All Informative Images
Decorative images (e.g., icons, dividers) should have empty alt text:alt=""
❌ Common Mistakes
Using generic text like "image" or "photo"
Stuffing alt text with multiple keywords
Leaving alt attributes blank on key visuals
Using the same alt text on all images
📊 Example Comparison
Bad Alt Text:
Good Alt Text:
🛠 Tools to Audit Alt Text
Screaming Frog SEO Spider
Ahrefs Site Audit
Google Lighthouse (DevTools > Lighthouse)
WAVE Web Accessibility Tool
These can help you find missing or poor-quality alt attributes on your site.
📌 Final Thoughts
Alt text may seem like a small detail, but it plays a big role in On-Page SEO and web accessibility. When used correctly, it improves your site’s visibility in image search, enhances user experience, and contributes to better search engine rankings.
Tip: Review all your existing images and add optimized alt text where missing.