When it comes to SEO, one area that’s often overlooked is image optimisation. But should it be? Can optimising your images really make a difference?
Absolutely!
Think about this: Google processes a whopping 3.5 billion searches every day, and about 3% of those (roughly 100.5 million searches) are for images. That might seem like a small percentage, but image SEO is much bigger than just appearing in image searches.
Done right, image SEO can improve your click-through rates (CTR) by showing images in snippets (like AI overviews) and even help you earn more backlinks. So, yes—it’s important, and it can bring results.
What is Image SEO?
Image SEO is all about making the images on your website more search-friendly. This helps search engines like Google understand your images better, so they can show them to the right people at the right time. Plus, it makes your site more enjoyable for users.
Where Can Images Show Up in Search?
A lot of people assume that image SEO only applies to images showing up in Google’s Image tab. But it’s more than that. Did you know that in the US, 39% of keywords trigger an image pack in the main search results? That means images appear right alongside traditional text-based listings.
This gives you more space on the search results page (which is great for getting attention), and it increases the chances someone will click on your listing.
And here’s something even cooler: AI-generated snippets are starting to include images, giving you another opportunity to stand out on the SERPs. But without good image SEO, search engines might not fully understand your images, which means they could miss out on opportunities to show them. Even though tools like Google Vision AI are improving how search engines “see” images, optimising them ensures better indexing and ranking.
How to Optimise Images for SEO
If you’re ready to improve your image SEO, here are some easy steps you can take:
1. Use Relevant Images
First things first—you need to have the right images. Look for visuals that add value, like:
- Product photos that show off what you’re selling
- Images that break up long blocks of text
- Infographics that explain an idea or process
- Graphs and tables for complex data
- Logos to represent your brand
- Screenshots that walk readers through a process
Whenever possible, try to use original, high-quality images. Stock photos can work in some cases, but unique images are always better. They tend to be more engaging and can help you stand out.
2. Pick the Right File Formats
There are a bunch of image formats out there, but Google only supports a few. Here’s what you should know:
- SVG: Perfect for logos and icons since they stay sharp at any size.
- WebP: Great for most other images because they load quickly and keep quality intact.
- JPEG: Use for standard images.
- PNG: Best for images with transparent backgrounds.
- GIF: Great for animations.
In most cases, WebP and SVG will give you the best results for SEO and page speed.
3. Use Clear and Descriptive File Names
Even though Google’s getting better at understanding images thanks to tools like Google Lens, it still relies heavily on text. This is where your file names come in. Be specific, clear, and include keywords to help search engines figure out what your image is about.
- Good example: apple-airpod-4-white-case-side-view.webp
- Bad example: IMG_2205325.jpg
Think of it like any other part of SEO—focus on being clear and relevant.
4. Write Effective Alt Text
Alt text is basically a written description of your image that helps search engines and people who use screen readers understand what’s going on in the image.
Here’s an example:
htmlCopy code<img src="image-file-example.jpg" alt="White Apple AirPods with charging case, side view">
Alt text is especially important for accessibility, and it can give your images an SEO boost. When writing alt text, stick to about 125 characters and avoid phrases like “image of” or “photo of.” Just describe the image as clearly as possible.
Need help? There are some great AI-powered tools out there, like Ahrefs’ alt text generator, that can assist with this.
5. Adjust Image Sizes for Performance
Make sure your images aren’t too big or too small. Large images can slow down your site, which hurts your Core Web Vitals and page speed. Small images, on the other hand, might look pixelated on larger screens. Use tools like Photoshop or WordPress plugins (like Resize Image After Upload) to adjust your image sizes automatically.
6. Compress Image File Sizes
Once you’ve adjusted the size, you might still need to compress the image to reduce its file size. This helps your pages load faster, which is key for SEO. Tools like TinyPNG, Optimole, or JPEG Optimize can help with compression while keeping quality intact.
7. Make Images Responsive
Your images should look good on any device—whether it’s a desktop, tablet, or smartphone. Responsive images automatically adjust to the user’s screen size, ensuring the best possible experience. Most platforms like WordPress or Wix do this for you, but if not, there are plenty of plugins available.
8. Use Lazy Loading for Faster Pages
Lazy loading delays the loading of images until the user scrolls to them, which can really speed up your site’s initial load time. Just add the loading=lazy attribute to your images, and watch your page load times (and rankings) improve.
9. Build an Image Sitemap
An image sitemap works just like an XML sitemap but focuses solely on images. This makes sure that search engines, like Googlebot, don’t miss any of your images when crawling your site. Tools like Yoast SEO or Screaming Frog can help you create one.
10. Use a Content Delivery Network (CDN)
A CDN stores copies of your site’s images on servers all over the world, so users can access them faster. This reduces load time and helps with SEO. Services like Cloudflare and Amazon CloudFront are great options.
11. Enable Browser Caching for Images
Browser caching allows returning visitors to load images faster by storing them locally on their browser. You can set different cache durations for different types of images (like a week for some, or even a year for logos) to improve performance.
12. Follow On-Page SEO Best Practices
Good image SEO works hand-in-hand with your overall on-page SEO. That means things like fast load times, well-written meta tags, and high-quality content all play a role in how well your images perform in search results.
13. Add Structured Data
Adding structured data (like schema markup) helps search engines better understand your images and display them in rich snippets. For example, if you run an e-commerce site, you might use Product schema to show off your product images. Check out Google Search Central for a full guide on how to do this.
Final Word: Image SEO
Now that you’ve got a solid understanding of image SEO, it’s clear why it shouldn’t be ignored. Optimising your images can lead to better CTR, more traffic, and even boost the number of backlinks to your site. And the best part? It’s all part of a broader SEO strategy that improves your site’s performance overall. So, if you haven’t already, it’s time to make image SEO a priority and watch the benefits roll in!
