Images SEO are great for improving user experience. But they can also slow down your website possibly even harming your SEO ranking if not optimized properly and when using on-page SEO, search engines take into account page speed, accessibility, and alt text, so image optimization is a part of on-page SEO.
In this guide, we will go through all the best practices for image optimization for SEO performance, website speed and user engagement.
The proper image format should compress the size of files without losing the quality. Some of the more popular formats include:
✔ JPEG – The top choice for photos and images with a lot of colors.
✔ PNG — Best for images with transparencies, but larger file size.
✔ WebP — A newer format which gives you high-quality images with small file sizes.
✔ SVG – Ideal for vector graphics such as logos and illustrations.
Best Practice:
Use WebP, if possible, for the best quality vs compression ratio.
Large image file sizes can also slow down the page loading speed, which can affect the SEO ranking. Then going back and compressing the images as much as possible (without making them too small) to increase performance.
Tools for Image Compression:
✔ TinyPNG – Efficiently decreases file sizes of PNG and JPEG.
✔ Image Optimization- Compress images without losing quality.
✔ ShortPixel -A really top notch plugin for image compression on WordPress.
✔ Squoosh -A fast and free online image compressor.
Best Practice:
Keep them 100KB or less, and they should load fine.
Search engines use image files names to understand what the images are about. Not just a generic name, such as “IMG123. jpg” to “best-water-filter-system-for-home-use.
Example:
❌ bad: img001. optimize-images-for-seo. jpg
✔ good: jpg
This allows search engines to index these images so people using the internet can find them, it also allows for visually impaired users to better access your website as your image will have a description.
Best Practices for Alt Text:
✔ Explain the image in simple and concise words.
✔ Use keywords but in natural way.
✔ Avoid keyword stuffing.
✔ Stay below 125 characters.
Example:
❌ bad: “SEO image optimization alt text example best practice”
✔ good: “An infographic illustrating SEO-friendly image optimization techniques.”
Lazy Loading to Improve Page Speed
Lazy loading loads images only when these are actually needed, increasing the speed of pages and lowering the stress on your server.
✔ HTML loading="lazy" attribute
✔ Install lazy-loading plugins for WordPress (example: WP Rocket, a3 Lazy Load)
✔ If needed, use lazy loading with JavaScript.
With Google’s mobile-first indexing, the fact that images should be mobile-friendly is another essential element of SEO.
Best Practices:
✔ Serve resolutions via secret in HTML for each image.
✔ Check mobile image loading speed via Google’s Page Speed Insights.
✔ Scale images for various devices properly.
Improving Image Sitemaps for Enhanced Indexation
The Sitemap for images helps Googlebot to crawl and index the images that are uploaded on your website.
Creating an Image Sitemap:
✔ Create an image sitemap automatically with Yoast SEO or Rank Math plugins.
✔ Manually add image URLs to your XML sitemap.
✔ (Image sitemap to be submitted to Google Search Console.)
Image context refers to the underlying description of the image and helps ensure it meets search engine algorithms.
Best Practices:
✔ Add JSON-LD Image Object schema.
✔ Add structured data for recipes, product images, infographics.
✔ Test the schema using Google’s Rich Results Test.
Knowing what to improve on tracking the images performance
Key Metrics to Track:
✔ Impressions from image search (Google Search Console).
✔ The speed of websites (Google Page Speed Insights).
✔ Image-related bugs (SEO auditing tools (Ahrefs, SEMrush)).
✔ Adding huge images that are not compressed and that slow down the site.
✔ Using Descriptive Alt Text
✔ Not updating filenames with relevant keywords.
✔ Ignoring lazy loading and responsive images. ⚙️ Structured data for images is ignored.
Of course, one of them is that optimized images increase website speed, improve the user experience, and improve search rankings.
WebP is better for a couple of reasons, file size and quality, which helps speed and performance.
Always check at intervals and optimize the newly uploaded images, particularly if the site has been updated/designed recently.
However, unique and original images should rank better in searches.
Tools such as Google Page Speed Insights or GTmetrix are what you should be using to track image loading times.
From the performance of the website to SEO, everything gets its hands-on optimization including images. In addition, accelerating page speeds and enhancing your search engine discoverability, with the right formats, compressed images, ALT text and lazy loading. Use these tips to improve your image SEO and get ahead of digital marketing!
