SEO for Images: Best Practices for Image Optimization

Matt Crowley - June 18, 2014

Imagery and multimedia enable webmasters to illustrate important concepts, tell stories, and otherwise engage their online audiences. But images that aren’t optimized cannot be easily understood by search engines. This makes for a less than optimal experience when it comes to SEO. In this post, we’ll look at the basic SEO best practices for image optimization.

Images are inherently difficult for search engines to read. Sure, there is Google image search, and even reverse image search, but search engines are only able to associate images that look like one another. If you have truly unique imagery (which you should!) then it will be far more difficult for a search engine to understand what each image is about, unless you employ basic SEO for images. Follow the steps below to ensure that you images meet the basic requirements of a well optimized asset.

Before Uploading your Images:

1. Save the image offline at the size that it will be used on your website. Uploading a very large image and then scaling it to a smaller size once it is on your website can be very problematic. It can lead to issues with design and / or page load time.
2. Save the image offline with a descriptive file name. The file name “image-14.jpg” is not descriptive. Instead, use words that describe the image. For example, the graphic to the right could be titled “elements-of-great-web-content-graphic.jpg.”
3. Compress your image files so that users are able to load them as quickly as possible.

After Uploading your Images:

1. Include a descriptive alt attribute for each image. This attribute is rarely seen by users, but provides a brief description of the image for search engines. We recommend using no more than 7 words for this attribute.
2. Associate the image with any relevant meta data such as OpenGraph protocol for Facebook, Rich Pin Markup for Pinterest, or schema.org for search engines.
3. Leverage social media sharing buttons when relevant. Does your audience use Pinterest? If so, be sure to include a Pin It button.
4. Create an image XML sitemap. XML sitemaps are extremely beneficial for ensuring that search engines can find all of the URLs on your website. This is true for images as well. Creating a separate XML sitemap that lists all your images can help search engines find and understand the images on your website.

Creating and using images throughout your website is the first step to ensuring that they play a strong role within your websites overall content strategy. Without optimizing these images, you are making it difficult for search engines to “see” your image content. And if your content can’t be seen, it’s harder for search engines to deliver it to users.