Alt text (alternative text, or the `alt attribute`) is a text description of an image embedded in the HTML `<img>` tag. It serves two main purposes: displaying when an image fails to load, and helping Google understand image content for ranking.
Why Alt Text Matters for SEO
- ▸Google can't "see" images the way humans do — alt text is how Google understands images
- ▸Alt text is a direct ranking signal in both Google Search and Google Images
- ▸Makes your website accessible to visually impaired users (screen readers)
- ▸Displays when images haven't loaded on slow connections
- ▸Used by Google as anchor text when an image is a link
A 2025 Semrush study of 800,000 pages found: 65% of pages with keyword-targeted alt text ranked in the top 10 of Google Images, compared to only 12% of pages without optimized alt text.
How to Write SEO-Optimized Alt Text — A Simple Formula
The best formula: **Describe what's in the image** + **Include your keyword naturally** + **Add context** (if needed). Keep it under 125 characters.
Examples for product images:
- ▸❌ Wrong: "product_image_1"
- ▸❌ Wrong: "shoes running shoes nike shoes sneakers buy"
- ▸✅ Right: "White Nike Air Max 270 running shoes for men 2026"
- ▸✅ Right: "Nike Air Max 270 white men's running shoes size 10"
Examples for blog/editorial images:
- ▸❌ Wrong: "image.jpg" or "screenshot"
- ▸❌ Wrong: "Image about image SEO optimization for websites"
- ▸✅ Right: "SEO Image Pro interface showing bulk image processing results"
- ▸✅ Right: "Screenshot of bulk EXIF metadata editor with 500 images processed"
5 Common Alt Text Mistakes to Avoid
- ▸1. Leaving alt="" blank on all images — Google has no idea what the image contains
- ▸2. Keyword stuffing: "shoes running shoes buy shoes online cheap" — Google penalizes this
- ▸3. Using the raw filename as alt text: "img_20260115_113045"
- ▸4. Using the same alt text for all images — image-level duplicate content
- ▸5. Starting with "Image of..." or "Picture of..." — redundant, Google already knows it's an image
Alt Text vs EXIF Metadata — Which One Should You Use?
This isn't a choice — you need both. Alt text is an HTML-level SEO signal (on-page), while EXIF metadata is a file-level signal. Google reads both and combines them to evaluate images.
In practice, EXIF metadata is especially important when images are shared, downloaded, or displayed on other platforms — alt text is lost, EXIF persists.
Managing Alt Text at Scale
For a website with hundreds of products, writing alt text manually for every image isn't practical. Solutions:
- ▸WordPress/WooCommerce: Bulk edit alt text with a plugin like Bulk Image Alt Text
- ▸Shopify: Use the Bulk Image Edit app
- ▸Custom website: Auto-generate alt text from filename or product title via script
- ▸EXIF metadata: SEO Image Pro writes EXIF Title — many CMSs auto-map EXIF Title to alt text