An Image Optimization Case Study: How To Use Photos To Drive Website Traffic

Sam Zastrow

Sam Zastrow

Sam Zastrow has worked in digital marketing for 9 years. He's a generalist with particular interests in B2B lead generation, analytics, and keyword strategy. Outside of the office, he enjoys hiking, travel, and following Aston Villa FC.

A few weeks ago, our site was experiencing record-setting levels of traffic. After a few moments of blissfully (and ignorantly) thinking our sound inbound strategy had set off some sort of viral content extravaganza we realized the real reason for the traffic. Almost all of it was coming from a single blog post or, more specifically, a single image within that blog post.

We'd recently written a blog post covering how to generate inbound leads and strengthen brand recognition. The post contained an image of a person-like figure pondering next to a large question mark. When we inserted the image, we used the alternate text “man with blue question mark.” It turns out this last step, adding alternate text to the image, was what drove all the traffic—more than 5,500 views in 10 days, as you can see in the traffic report below.


Source: HubSpot

The alt text, "man with blue question mark," ranked very highly on Google image searches for "question mark," "blue question mark," and "?." So a good chunk of people making this simple search were directed to our site, boosting our traffic several hundred percent the following week. Now, this wasn't exactly what you'd call "high-quality traffic," as the bounce rate for these searchers was probably quite high. But this example illustrates the power of optimizing images for search.

Google search can be difficult to understand, but knowing how to optimize images is something even the most novice webmasters can gain from. Here are a few tips to optimize images on your website:

  • Use descriptive image alt text, captions and titles. Enter a keyword-laden description of the image into its alt text field. This makes it much easier for Google to identify exactly what the image is. Using what you entered in the alt text field as a title and in the caption is a good idea, too.
  • Use descriptive filenames for images. Similarly, provide a succinct description of each image in its filename. For example, you'd be better served with "man-with-blue-question-mark.png" than" IMG4881392.png."
  • Provide context for the image in the page copy. Referring to the image in a descriptive manner near it on the page helps associate it with the text and makes it easier for search engines to figure out what the image is. (You'll notice I did this by referring to the graph above in the paragraph immediately preceding it.)
  • Include images in your Sitemap. A Sitemap is a tool that essentially provides an information guide to search engines so it picks up on pages it might otherwise miss. Similarly, you can include image files in this map (or in a separate map of their own) to make sure search engines index all of your images. You can even highlight the images you deem as most important. You can find a more extensive explanation of Sitemaps and how Google uses them here.
  • Only use image file types supported by Google. These include JPEG, PNG, GIF, BMP, SVG and WebP.

Not sure where to start when it comes to optimizing the images on your business' website? We can help.

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