Optimise Ecommerce Images for SEO

Learn how to optimise ecommerce images for SEO to boost rankings, improve site speed, and increase conversions for online shops.

At Lillian Purge, we specialise in SEO for Ecommerce. Find out how to optimise ecommerce images for SEO and better rankings.

Optimising ecommerce images for SEO is about more than just making your website look good. It’s about ensuring that every image contributes to your site’s visibility, speed, and user experience. Search engines rely on text-based data to understand images, so if your product photos aren’t properly optimised, you’re missing valuable ranking opportunities.

Why Image SEO Matters for Ecommerce

Images are the backbone of any ecommerce website. They influence buying decisions, build trust, and showcase your products. However, large, unoptimised files can slow down your site, hurting both user experience and search rankings.

Image optimisation ensures that visuals are clear, lightweight, and descriptive enough for both customers and search engines. When done correctly, it can improve page speed, boost organic traffic, and even increase conversions.

What Image Optimisation Involves

Image optimisation refers to the process of reducing file sizes, improving accessibility, and enhancing discoverability without compromising visual quality. For ecommerce sites, this means:

Compressing image files for faster load times.
Naming files descriptively with relevant keywords.
Adding alt text that accurately describes the product.
Choosing the right file format for performance.
Structuring images for mobile users and accessibility.

The goal is to create a seamless shopping experience that loads fast, looks great, and supports SEO objectives.

How to Optimise Ecommerce Images for SEO

1. Choose the Right File Format

Selecting the right image format affects both quality and performance. For most ecommerce stores, JPEG is the best choice for product photos as it balances clarity and file size. PNG works well for transparent backgrounds or logos, while WebP provides excellent compression for modern browsers without visible quality loss.

When possible, use WebP for your main images since it can reduce file sizes by up to 30 percent compared to JPEG, improving page speed significantly.

2. Resize Images to the Correct Dimensions

Uploading unnecessarily large images is a common mistake. Always resize images to the dimensions they’ll appear on your website. For example, if your Shopify or WooCommerce product image container displays at 800px wide, there’s no need to upload a 3000px file.

Smaller file sizes load faster, which helps with both SEO and user experience.

3. Compress Images Without Losing Quality

Image compression reduces file size while maintaining quality. Tools like TinyPNG, ShortPixel, or ImageOptim can automatically compress files before upload. Many ecommerce platforms, including Shopify and WordPress, also have plugins that compress images automatically on upload.

Aim for the smallest file size possible without visible quality loss. A typical optimised product image should be under 150KB.

4. Use Descriptive File Names

Search engines read file names to understand image content. Instead of using default names like “IMG_0023.jpg,” rename files to something descriptive, such as “black-leather-wallet-men.jpg.”

File names should be clear, concise, and keyword-rich but natural. Avoid keyword stuffing or unnecessary repetition.

5. Write Accurate Alt Text

Alt text (alternative text) serves two purposes: it makes your site accessible to visually impaired users and helps search engines understand what your image represents.

Good alt text should describe the image in context. For example: “Handmade black leather wallet with card holder slots.”

Avoid phrases like “image of” or “photo of,” as search engines already know it’s an image. The key is to make it descriptive enough for someone who can’t see it to understand what’s shown.

6. Optimise Image Titles and Captions

While alt text is the most important for SEO, titles and captions also add context. Titles appear when users hover over an image, and captions can provide additional product information.

Keep them relevant and consistent with the page’s target keywords. This not only improves SEO but also enhances user engagement.

7. Use Structured Data for Product Images

Structured data, or schema markup, helps search engines display your product images in rich results such as Google Shopping or image search. Adding schema to your product pages allows Google to understand price, availability, and image relationships.

Platforms like Shopify and WooCommerce often include product schema by default, but you can validate it using Google’s Rich Results Test to ensure images are being picked up correctly.

8. Enable Lazy Loading

Lazy loading delays the loading of off-screen images until the user scrolls down to view them. This improves perceived page speed and overall performance.

In WordPress, lazy loading is enabled by default. Shopify also supports it through modern themes or lightweight scripts. For custom-built ecommerce sites, adding a simple JavaScript snippet can achieve the same effect.

9. Create an Image Sitemap

An image sitemap helps search engines discover images that might not be found through normal crawling. It lists all the image URLs and their corresponding pages.

If you’re using WordPress, SEO plugins like Rank Math or Yoast automatically generate image sitemaps. Submitting these through Google Search Console ensures all your product images are indexed correctly.

10. Ensure Mobile Optimisation

Since most ecommerce traffic comes from mobile devices, images must load quickly and look sharp across all screen sizes. Use responsive design so images scale correctly and avoid forcing mobile users to load desktop-sized files.

Google’s PageSpeed Insights can help identify mobile image issues that need addressing.

Challenges in Ecommerce Image SEO

Optimising thousands of product images can be time-consuming, particularly for large online stores. Some sellers rely too heavily on automatic compression, which can reduce quality, while others upload overly large files, slowing their site down.

Another challenge is maintaining consistency across all product images. Mismatched dimensions or styles can hurt visual appeal, even if SEO is well executed. Using templates and image guidelines for your team or suppliers helps ensure standardisation.

Complementary Strategies

Image optimisation is most effective when combined with other on-page SEO tactics. For best results, pair it with:

Optimised product titles and meta descriptions.
Fast, secure hosting for your ecommerce site.
Internal linking between related products.
Structured category pages that support crawlability.
A strong backlink profile to build authority.

These elements work together to improve overall visibility and conversion performance.

Expert Tips for Image SEO

Batch process your images before upload using an image editor or optimisation tool.
Test your site speed regularly after uploading new images.
Replace outdated product photos with newer, higher-quality versions.
Keep file naming consistent with your brand and product categories.
Regularly audit your alt text to ensure it reflects your keyword strategy.
Avoid decorative or duplicate images that don’t add value to the user experience.
Consider using CDN (Content Delivery Network) hosting for faster global image delivery.

Final Thoughts

Image SEO might seem like a small part of ecommerce optimisation, but it plays a major role in how your store performs in search and how customers experience your brand. Fast-loading, well-structured, and properly described images not only attract more visitors but also convert them more effectively. By combining technical precision with visual consistency, your ecommerce store can gain a significant competitive edge.