10 Image SEO Mistakes That Are Killing Your Rankings

Most websites make the same image SEO mistakes. Each one costs rankings, traffic, and conversions. Here are the 10 most common mistakes — and exactly how to fix them.

Mistake 1: Missing Alt Text

What's happening: Images have no alt attribute at all.

Impact: Screen readers announce the filename. Google cannot understand the image. Zero image search visibility.

Fix: Add descriptive alt text to every informative image. Use our free alt text generator to speed this up.

Mistake 2: Generic Alt Text

What's happening: Alt text like "image", "photo", "picture", or the filename.

Impact: Provides no useful information to Google or users.

Fix: Describe what's actually in the image specifically and accurately.

Mistake 3: Keyword Stuffing in Alt Text

What's happening: Alt text like "buy shoes cheap shoes sale shoes trainers".

Impact: Google penalises this as spam. Also creates terrible user experience for screen reader users.

Fix: Include one primary keyword naturally. Write for humans, not algorithms.

Mistake 4: Using the Same Alt Text on Multiple Images

What's happening: Multiple product images on a page all have identical alt text.

Impact: Duplicate content signals. Google may struggle to determine which image is most relevant.

Fix: Each image gets unique alt text that describes that specific image.

Mistake 5: Not Compressing Images

What's happening: 5MB photos uploaded directly from cameras.

Impact: Severely slow page load times. Poor Core Web Vitals scores. Lower rankings.

Fix: Compress all images to target sizes before upload.

Mistake 6: Bad File Names

What's happening: Files named IMG_1234.jpg, DSC_0056.jpg.

Impact: Missed keyword opportunity in a signal Google does read.

Fix: Rename files descriptively before uploading.

Mistake 7: Using PNG for Photos

What's happening: Photographs saved as PNG files.

Impact: PNG files for photos are 5-10x larger than equivalent JPEGs.

Fix: Use JPEG for photographs. Only use PNG when transparency is needed.

Mistake 8: No Dimensions on Images

What's happening: img tags without width and height attributes.

Impact: Cumulative Layout Shift (CLS) — content jumps as images load. Bad Core Web Vitals score.

Fix: Always specify width and height: <img src="photo.jpg" width="800" height="600" alt="...">

Mistake 9: Lazy Loading Hero Images

What's happening: loading="lazy" applied to above-fold hero images.

Impact: Dramatically worsens LCP (Largest Contentful Paint).

Fix: Never lazy load images that are visible without scrolling.

Mistake 10: Not Submitting an Image Sitemap

What's happening: Images on JavaScript-heavy pages not discovered by Google.

Impact: Images never indexed, never shown in image search.

Fix: Create an image sitemap and submit it in Google Search Console.

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