How to Optimize Images for SEO [Complete Guide]

An aspect that is often forgotten in the work with search engine optimization, SEO, is the optimization of images. They work on optimizing the website’s structure, improving the website’s content, and building links. But in this work, the role of SEO-optimizing the images on the website is often overlooked.

In fact, a successful SEO strategy is about the big picture. As you know, the search engines use hundreds of ranking factors in their algorithms to determine where a page should rank in the search results. To really maximize the results with SEO, it is therefore important to work with all parts of SEO, including images.

In this article, we will therefore focus on how you can improve your website performance and visibility by focusing on image SEO optimization.

Why are SEO-optimized images important?

Images and other visual elements have become an increasingly important part of SEO and website optimization in recent years. This is basically because we humans are visual creatures who find it much easier to understand an image than a long text. Also, the old saying “a picture is worth a thousand words” applies.

Furthermore, images are a great way to break up long texts and make a page more appealing, improving the user experience and extending the time users spend on your website.

For these reasons, images therefore have an important role to play in SEO optimization. The first step is of course to use images but the second step is to optimize them for SEO. here are the top reasons why SEO-optimizing images is important:

Faster load times

One of the main factors that affect the user experience of a website is its speed and how quickly it loads. Large and unoptimized images are often one of the main things that contribute to a slow website.

Large images can therefore significantly increase the load time of your website. Optimizing the size of images and improving their load time creates a smoother and more responsive user experience, which in turn reduces the risk of visitors leaving your site quickly. Since the user experience is central to SEO, this is of course incredibly important for better rankings in the search engines

Reduced bounce rate

Bounce rate is another important component that search engines keep in mind. If a lot of users come to your site and then leave it right after, it indicates that they had a bad user experience or didn’t find what they were looking for. That being said, you want to work to reduce the bounce rate as much as possible.

SEO-optimized images play an important role in creating a visually appealing page while loading quickly. By minimizing the bounce rate, you increase the chance that visitors will stay longer and can thus be rewarded with better rankings in the search engines.

The importance of image search results

Something that many people often forget is that search results are not just specific web pages with text. Google also has an image search function that is widely used. Unfortunately, many website owners overlook this.

In other words, to improve your visibility in image searches, you can drive more traffic to your website that way. Working with SEO for images can therefore help drive more traffic to your page, which is the whole purpose of SEO work. But since most people don’t work with image SEO, it means that the competition is lower, which gives those who work actively with it a clear advantage.

Google’s focus on user experience and relevance

As discussed earlier, user experience is central to search engines. They want their users to be satisfied with the search results they recommend and to provide answers to any questions they have. Therefore, including SEO-optimized images on your website helps to reinforce this and signals to the search engines that your website offers high-quality and relevant visual content. This can lead to an improved positioning in the search results and increased visibility towards your target group.

Basic principles of SEO optimization of images

Now that you understand the importance of SEO optimization of images, you are probably wondering how to do it. There are several different components of image optimization for SEO so let’s take a closer look at these.

Selection of the right image format (JPEG, PNG, GIF)

First of all, you need to choose the optimal aspect ratio for your images. This is a key factor in balancing image quality and file size. JPEG is good for photographs and images with many shades of color, while PNG is more suitable for images with transparent backgrounds and images with a high level of detail. GIF should be used for simple icons or graphics with few colors. Be sure to select the most appropriate image format depending on the type of image to ensure both quality and efficiency.

Image compression for faster loading

Image compression is incredibly important to reduce file size and thus increase the loading speed of your website without losing quality.

Use various compression tools to optimize the size of your images and ensure fast loading times.

Use descriptive filenames

An important part of image SEO is using descriptive filenames so search engines can understand what the image is about. Avoid generic file names like “IMG001.jpg” and instead choose something that clearly explains what the image is about. This helps search engines understand and index the image correctly and thus present the image for relevant search terms.

Write meaningful alt texts for accessibility and SEO

Alt texts are perhaps the most important part of image optimization for SEO. It gives search engines additional information about the content of the image and helps it rank better. Describe the image clearly and concisely and use relevant keywords without over-optimizing.

Use of correct image sizes

As discussed earlier, the right image sizes and optimization of the image sizes are central to good rankings, faster loading times, and improved results in search engines.

1. Adapt to different devices and screen sizes
   First of all, you want to ensure that your images are responsive and adapted to different devices and screen sizes. Using a responsive design automatically resizes images based on the visitor’s device, preventing large images from loading on small screens and vice versa. This is incredibly important for a positive user experience and also affects the page’s ranking in Google’s mobile indexing.
2. Prioritize load times for mobile devices
   As you probably know, a majority of users today use mobile phones. Because of this, mobile users are technically more important than desktop users. That being said, you need to pay close attention to optimizing image sizes for fast load times on mobile networks. By limiting the file size and dimensions of images, you can improve performance and reduce user wait times.
3. Lazy loading to delay loading of images outside the view
   Lazy loading is a technique that means that images are not loaded until they enter the user’s field of view. This reduces initial page load time and avoids all images needing to load at once. In this way, you avoid the user using an unnecessary amount of data and also increase the speed of the page.
4. Adaptive image management using CSS and HTML
   Another tip is to use CSS and HTML to adjust the image sizes based on the screen resolution and size. Having different image versions for different devices and screens optimizes the user experience and also minimizes unnecessary data transfer for users with less capacity on their devices.

Implementation of structured data for images

1. Schedule Markup
   Also known as structured data, Schema Markup is a special type of HTML coding that provides search engines with additional information about the content of the website. In the case of images, Schema Markup enables a detailed description of each image with details such as its meaning, location, and other relevant details. This is therefore a way of giving search engines additional information about your images to help them appear higher in search results.
2. Benefits of Schema Markup for SEO
   Schema markup helps increase the visibility of your images on search engine results pages (SERPs). This is because structured data gives search engines a better understanding of the content and increases the chances of your images appearing as “rich results” meaning previews or additional information directly in the search results.
3. Using JSON-LD for structured data
   The implementation of Schema Markup for images can be done using JSON-LD (JavaScript Object Notation for Linked Data). This provides a simple and clear method for including structured data in the web page source code. By adding relevant markup codes directly to HTML, you help search engines understand the visual content at a deeper level.

4. Descriptive properties and metadata
   When using Schema Markup for images, it’s important to include descriptive properties and metadata such as titles, captions, copyright information, and any related links. This gives search engines a better understanding of each image and also creates a more informative user experience when images appear in search results or as part of “rich results”.
5. TinyPNG and JPEG Optimizer
   TinyPNG and JPEG-Optimizer are two tools that compress images without compromising quality. TinyPNG focuses on PNG images while JPEG-Optimizer specializes in the JPEG format. These two tools are something anyone optimizing images for SEO should use to reduce file sizes and improve page load times.
6. ImageOptim
   ImageOptim is a powerful tool for Mac users that automatically minimizes image sizes without losing visible quality. In addition, it supports various image formats, including JPEG, PNG, and GIF.
7. Google PageSpeed Insights
   PageSpeed Insights is a tool from Google that evaluates your website performance and provides specific recommendations for image optimization. This is a tool you should definitely use to gain better insights into how to improve your site’s speed and user experience, two components that are absolutely central to successful SEO.
8. Web.dev by Google
   Last but not least we have Web.dev which is developed by google. Here you will find a variety of valuable resources for web developers such as guides and tools to improve the performance of your website. You get tips on image optimization, mobile adaptation, and other important ways to improve your page.

It provides insights into image optimization, mobile optimization and other critical aspects of web development.