The visual side of a website is undoubtedly important. It attracts attention and helps communicate your message. Yet even the most beautiful graphics can have a negative impact on your website's performance and its position in search engines (SEO) if they are not properly optimised. Let us look at how images affect loading speed, Google's assessment and user satisfaction, and what you can do to put things right.
Why is website loading speed so important?
Page loading speed is not just a matter of user convenience; it is a fundamental factor that directly affects the success of your website. Google officially confirms that it takes website speed into account when ranking pages in search results, especially on mobile devices. A faster website can therefore mean better visibility in search engines.
The impact on user experience is just as important. A slower website leads to a higher bounce rate. This term refers to the percentage of visitors who arrive on one page of your website and leave immediately without taking any further action (such as clicking a link). If, for example, 600 out of 1,000 visitors leave the page without interacting, your bounce rate is 60%.
People on the internet are impatient. If your website takes more than a few seconds to load, users often lose interest, close the browser tab, go back to the search results and move on to a competitor. Data from Google shows that increasing the loading time from 1 to 3 seconds can raise the probability of a bounce by up to 32%. With loading times over 5 seconds, the bounce rate can reach 90% or more.
Most at risk from slow loading are online shops, where a few seconds' delay can mean a lost customer, blogs and magazines, where the reader can easily find a faster source of information, and single-page websites (landing pages), which need to grab attention with their content immediately.
A high bounce rate then has several negative consequences:
- Lost potential customers: Every extra second of loading time can mean tens of percent of lost orders or enquiries.
- Worse SEO ranking: Google may judge your page to be of lower quality or less relevant to users if they leave it quickly.
- Wasted advertising money: If you pay per click (for example in Google Ads) and visitors leave immediately, your advertising investment is ineffective.
The most common problems with website graphics
Which graphic sins most often slow websites down?
- Oversized images: Images are often uploaded with far larger dimensions (for example 3,000 pixels wide for a small icon) than are needed for display on the page.
- Large files: Related to this is the unnecessarily large file size of images (megabytes instead of kilobytes).
- Unsuitable file formats: Using formats such as PNG for photographs, where the more economical JPEG or more modern formats would be more appropriate.
- No lazy loading: Loading all the images on a page as soon as it opens, including those the user cannot yet see.
- Missing alternative texts (alt tags): These descriptions are important not only for SEO but also for the accessibility of the website for visually impaired users.
How to optimise graphics for the web properly
Optimising graphics is not complicated, but it does require consistency. Here are the key steps:
1. Reduce image dimensions: Before uploading to the web, resize images to the maximum size at which they will actually be displayed on the page. If, for example, you have an article thumbnail 350 pixels wide, there is no point uploading the original image at 2,000 pixels wide.
2. Compress images: After adjusting the dimensions, use compression tools that reduce the file size without any visible loss of quality. Online tools such as TinyPNG are popular.
3. Use modern formats: Formats such as WebP (developed by Google) or AVIF offer significantly better compression than traditional JPEG and PNG, often by 30–80%, while maintaining comparable or even better visual quality. AVIF also supports advanced features such as HDR and animation, so it can replace even animated GIFs at a much smaller file size.
4. Implement lazy loading: This technique delays the loading of images (or other elements, such as videos in an iframe) until the user scrolls down the page and the image enters the visible area of the browser. Instead of all images downloading at once when the page opens, they load progressively as needed. Modern browsers and content management systems such as Joomla 4 often support this natively using the loading="lazy" attribute
5. Do not forget ALT texts: Filling in the alternative text (alt attribute) for every image helps search engines understand the content of the image and improves the accessibility of the website. The description should be brief and to the point. For example:
<img src="/boat-on-the-lake.webp" alt="Fast aluminium boat on a calm lake at sunset">What do you gain by optimising graphics?
The time invested in optimising images will pay for itself many times over. Speeding up your website's loading can lead to:
- Better positions in search engines and higher organic traffic.
- A lower bounce rate, because users will not leave due to slow loading.
- Higher conversions (more orders, enquiries, registrations).
- Better Core Web Vitals scores. The metrics Google uses to assess user experience (LCP, FID, CLS).
Bonus: recommended tools
These tools can be useful for measuring and optimising the performance of your website and graphics:
- Lighthouse: A tool built into Chrome DevTools for a comprehensive website audit, including performance.
- PageSpeed Insights: An online tool from Google that analyses page speed and provides specific recommendations.
- Graphics editors (Figma, Canva, Photoshop): Let you export images directly in optimised formats and sizes.
- Online converters (for example WebP Converter): For bulk conversion of images to modern formats.
Optimising graphics is an essential part of building a fast and successful website. Do not underestimate its influence and give it the attention it deserves; your users and the search engines will thank you.
Did you know that low user engagement can lead to pages being removed from search results?
Google has confirmed that if users do not interact with your page in the search results, for example by not clicking on it, it may remove the page from the results or even drop it from the index entirely. Even if a page is in the sitemap and has been successfully indexed, it may still not appear in search results if Google judges that other content provides a better answer to a specific query.
The reason may be that the query is unusual or rarely searched for, or that your content is not of sufficient quality or relevance.
So if Google notices that your page repeatedly fails to attract users' attention, it may be removed from the results even though it was originally considered useful. This means it is not enough to have a technically well-configured website with a sitemap; the key is for the content to be genuinely useful, attractive and to motivate users to interact. Creating quality content that answers users' real questions and engages them therefore plays a fundamental role in whether your pages stay in Google's index. Read how to start a successful blog step by step.