How To Easily Optimise Images And Boost Your Website Performance

Laggy load times are the worst. There’s little more infuriating than clicking through to a website and finding it blank, because the images are so humongous they’ve not loaded yet. Most people, to be honest, don’t bother waiting for them to load. They just click back and find another option. It takes less time for them to return to the SERPs and click through to another site that loads so fast it appears instant, than it does to wait for your laggy images to load. Failing to optimise images on your website is one of the biggest mistakes people make.

It’s also one of the most underestimated ones. It doesn’t seem like a big thing. But these days, the performance of a website is paramount. Not just for providing a superior user experience but also for achieving higher rankings in search engine results. Those two things are inextricably linked, and each year the Google gods are giving ever-greater priority to user experience. And laggy load times caused by unoptimised images are a killer when it comes to UX. 

Why should you care about optimising your images? Because the algorithms do. Website speed is a critical ranking factor. When users visit a website, they expect a seamless and fast loading experience, regardless of the device they are using. A delay of even a few seconds in page load time can lead to increased bounce rates, decreased engagement, and ultimately, a loss in potential conversions. This makes website performance optimisation an essential aspect of both user satisfaction and search engine optimisation (SEO) strategy.

One of the most effective ways to enhance website performance is through the optimisation of images. Images often account for the majority of a webpage’s data, and without proper optimisation, they can significantly slow down page load times. 

But how exactly do you optimise your images? Let’s dig in…

Understanding Image Optimisation

Image optimisation is a critical process for any website aiming to improve its loading times, enhance user experience, and boost its SEO rankings. At its core, image optimisation involves reducing the file size of your images as much as possible without sacrificing quality, so your website loads faster for visitors. This balance is crucial because while high-quality images are essential for engaging users and conveying your website’s message, large image files can significantly slow down your site.

The direct link between image Optimisation and web performance cannot be overstated. Websites with optimised images load quicker, consume less bandwidth, and provide a smoother experience for users across all device types. For mobile users, who may be on slower or limited data plans, this is especially critical. Optimising images not only helps in retaining users but also plays a pivotal role in improving the visibility of your site on search engines. Faster websites are ranked better by search engines, leading to higher visibility, more traffic, and potentially, more conversions.

Achieving the right balance between image quality and file size is the essence of image optimisation. This balance ensures that your website offers an appealing visual experience without compromising on speed. 

Reasons to Optimise Your Images

Image Optimisation is not just a technical step towards a faster website; it is a crucial element that impacts every aspect of a site’s success, from user engagement to search engine rankings. Understanding the reasons to optimise your images can help underline the importance of this practice.

Impact on Page Loading Times and User Experience

The size of images directly affects the loading times of web pages. Large, unoptimised images are the main culprits behind slow-loading pages, a major deterrent for website visitors. In an age where attention spans are short, users expect websites to load almost instantaneously. Pages that take more than a few seconds to load are likely to frustrate users, leading to a poor user experience. This dissatisfaction is often reflected in higher bounce rates as users abandon slow-loading sites in favour of faster alternatives. Optimising images reduces their file size, which in turn speeds up page loading times, enhancing the user experience and keeping users engaged with your content longer.

Influence on SEO

Search engines like Google use page speed as a ranking factor, meaning that faster websites have a better chance of appearing higher in search results. By optimising your images, you contribute significantly to your website’s overall speed and performance, which can improve your SEO rankings. Furthermore, optimised images require less bandwidth to load, which is particularly beneficial for users on mobile devices or limited data plans. This inclusivity in user experience is something search engines favour, aligning with their goal to deliver the best possible results to users regardless of their browsing conditions.

Benefits for Mobile Browsing

The rise of mobile internet usage has made mobile browsing performance a critical consideration for website owners. Mobile users expect the same level of performance and speed as desktop users, despite the limitations of mobile networks and devices. Large, heavy images can drastically affect mobile site speed, leading to increased frustration and a higher likelihood of users abandoning the site. Optimising images not only helps in speeding up load times for mobile users but also ensures that your site is accessible and user-friendly across all devices and connection speeds. This accessibility is crucial for reaching a wider audience and can significantly impact your site’s traffic and engagement levels.

Types of Image Compression

Image compression is a technique used to reduce the file size of images, which is essential for improving website performance. There are two main types of image compression: lossy and lossless. Understanding the differences between these types and knowing when to use each is crucial for effective image optimisation.

Lossy Compression

Definition: Lossy compression reduces file size by permanently removing certain information from the image. This process results in a loss of quality, which can vary from negligible to significant depending on the compression level applied.

When to Use: Lossy compression is best used for photographs and complex images where a slight loss of quality is not noticeable to the average viewer. It’s particularly effective for web images where the balance between quality and speed is crucial. Formats like JPEG are typically associated with lossy compression.

Lossless Compression

Definition: Lossless compression reduces file size without any quality loss, meaning the original image can be perfectly reconstructed from the compressed image. This is achieved by efficiently encoding the image data rather than removing it.

When to Use: Lossless compression is ideal for images where every detail is important, such as logos, text, or images containing sharp lines and contrasts. It is also preferred when images will undergo further editing or processing. Formats like PNG and GIF use lossless compression.

Overview of Common Image Formats and Their Best Use Cases

JPEG (Joint Photographic Experts Group): Best for photographs and realistic paintings due to its ability to handle colours and gradients smoothly. JPEG uses lossy compression, allowing for smaller file sizes at the cost of some quality loss.

PNG (Portable Network Graphics): Ideal for images requiring transparency or images with text, sharp edges, and significant contrast. PNG uses lossless compression, ensuring no quality loss and supporting transparency, making it perfect for logos and icons.

GIF (Graphics Interchange Format): Suitable for simple animations and images with a limited colour palette. GIF uses lossless compression but is limited to 256 colours, making it less ideal for full-colour photographs.

WebP: A relatively new format developed by Google, WebP supports both lossy and lossless compression. It provides superior compression compared to JPEG (for lossy) and PNG (for lossless), making it a versatile choice for all types of web images. WebP offers the benefits of both JPEG and PNG formats, including transparency and animation support, often with smaller file sizes.

Choosing the right image format and compression type is key to Optimising your website’s images effectively. By understanding the strengths and limitations of each format and compression method, you can ensure that your website loads quickly while maintaining the visual quality of your images.

Tools and Techniques to Optimise Images

Optimising images for the web is a critical step in improving website performance. Fortunately, there are numerous tools and techniques available, ranging from manual software options to automated services and plugins. Whether you’re a professional web developer or a website owner with minimal technical expertise, there’s a tool that can simplify the image optimisation process for you.

Software and Online Tools for Manual Image Optimisation

Adobe Photoshop: A powerful, industry-standard software that offers extensive features for image editing and optimisation. Photoshop allows users to manually adjust the quality and size of images, choose the optimal format, and use the “Save for Web” option, which provides a balance between image quality and file size.

GIMP (GNU Image Manipulation Program): A free and open-source alternative to Photoshop, GIMP offers robust features for image editing, including resizing, cropping, and compressing images without significant quality loss. It’s suitable for those who need a comprehensive editing tool without the cost of premium software.

TinyPNG/TinyJPG: These are online tools that use smart lossy compression techniques to reduce the file size of PNG and JPEG images. By selectively decreasing the number of colours in the image, they achieve significant reductions in size without visibly affecting the quality. These tools are user-friendly and ideal for quick optimisations without the need for software installation.

Automated Image Optimisation Services and Plugins

Imagify: An online service and WordPress plugin that automatically Optimises images as you upload them to your website. It offers options for different levels of compression (normal, aggressive, and ultra), making it easy to balance image quality and performance. Imagify can also convert images to WebP format for further performance improvements.

ShortPixel: Another excellent service that provides both lossy and lossless image compression. It’s available as an online tool and a WordPress plugin, supporting various image formats including JPG, PNG, GIF, and WebP. ShortPixel is known for its ability to Optimise images in the background, ensuring that your website’s performance is continuously improved without manual intervention.

WP Smush: Specifically designed for WordPress websites, WP Smush automatically compresses images on upload and can also bulk smush previously uploaded images. It focuses on preserving image quality while reducing file size and supports lazy loading to further speed up your website.

These tools and techniques offer a range of options for optimising images, whether you prefer hands-on control over every detail or automated solutions that handle the process for you. By selecting the right tools for your needs, you can significantly improve your website’s load time, user experience, and SEO performance, all through the power of image optimisation.

How To Optimise Images: A Step-by-Step Guide

Optimising images for the web involves several key steps that can significantly improve your website’s loading speed and performance. This guide will walk you through the process, from choosing the right format to implementing advanced techniques like lazy loading.

1. Choosing the Right Format

Content Type Analysis: Determine the type of content your image will display. Use JPEG for photographs and realistic images due to its efficient compression methods. For graphics with sharp edges, text, or transparency, PNG is more suitable. GIF is ideal for simple animations. Consider WebP for its versatility and superior compression algorithms that work well for both types of images.

Format Selection: Choose a format based on your analysis. Keep in mind that newer formats like WebP offer benefits across both photographic and graphic images, often with better compression ratios than traditional formats.

2. Resizing Images

Determine Optimal Display Size: Assess the largest size your images will be displayed at on your website. There’s no need to use an image larger than its maximum display dimensions.

Use Image Editing Tools: Tools like Photoshop or GIMP can resize images. When resizing, maintain the aspect ratio to avoid distorting the image. Aim for the dimensions that match your layout needs while keeping the file size down.

3. Compression

Choosing Compression Type: Decide between lossy and lossless compression based on your quality requirements. Use lossy compression for web photos where slight quality loss is acceptable for significant size reduction. Opt for lossless for images where detail is crucial.

utilise Compression Tools: Leverage tools like TinyPNG or online services like Imagify for automating the compression process. These tools often offer the ability to adjust the compression level to find the right balance between quality and file size.

4. Using Responsive Images

HTML5 <picture> Element: Use the <picture> element to define multiple source images for different screen sizes and resolutions. This allows browsers to download the most appropriate version, saving bandwidth and improving load times.

CSS Media Queries: Alternatively, use CSS media queries to serve different background images based on device screen sizes. This method works well for images used as part of your design rather than content.

5. Lazy Loading

Implementation: Lazy loading defers the loading of images not in the viewport. Images are only loaded as the user scrolls down, improving initial page load time.

Using HTML Attribute: The loading=”lazy” attribute on <img> and <iframe> elements is the simplest way to implement lazy loading. This native lazy loading is supported by most modern browsers.

JavaScript Libraries: For more control or for browsers that do not support the loading=”lazy” attribute, use a JavaScript library like Lozad.js or LazySizes to implement lazy loading.

By following these steps, you can significantly reduce the impact of images on your site’s load time. Remember, Optimising images is not just about reducing their size; it’s about ensuring that your site delivers the best possible user experience across all devices and connection speeds.

Optimising Your Image Metadata

Beyond resizing and compressing your images, another crucial step in the optimisation process involves the careful management of image metadata. Metadata, which includes information like titles, descriptions, and tags, plays a significant role in SEO and accessibility.

Importance of Image Metadata

SEO Benefits: Search engines use metadata to understand and index images more accurately. Well-crafted titles and alt text (alternative text) can improve your images’ visibility in search results and contribute to the overall SEO strength of your page.

Enhancing Accessibility: Alt text is essential for screen readers used by visually impaired users. It describes the image content, ensuring that all users can understand images on your site, enhancing the site’s accessibility.

Improving User Engagement: Metadata can also include captions or descriptions that appear on hover or when an image is clicked. These can provide additional context to images, improving user engagement and retention.

How to Optimise Image Metadata

Alt Text: Write descriptive, concise alt text for each image, incorporating relevant keywords without keyword stuffing. Alt text should accurately describe the image content, helping both search engines and users who rely on screen readers.

Image Titles and Filenames: Choose descriptive filenames before uploading images to your site. Including keywords and separating words with hyphens (e.g., “how-to-optimise-images.jpg”) can improve SEO. Similarly, the image title tag can be used to provide additional context.

Captions and Descriptions: While not always necessary, adding captions or descriptions to images can improve user engagement, especially for images that convey important information or are meant to invoke a response from the user.

EXIF Data: Although not directly related to SEO, stripping unnecessary EXIF data (camera settings, geolocation, etc.) from images can reduce file size further, improving load times. However, for photography websites, retaining some EXIF data can add value by providing details about the photograph.

By paying attention to image metadata, you can enhance your website’s SEO, accessibility, and user engagement. This step, often overlooked, is a simple yet effective way to ensure your images fully contribute to your website’s performance and visibility.

Advanced Strategies

Beyond the basic steps of optimising images, there are advanced strategies that can further enhance your website’s performance and user experience. Leveraging a Content Delivery Network (CDN) and Utilising next-generation image formats are two powerful approaches.

Role of CDN in Optimising Image Delivery

A Content Delivery Network (CDN) is a network of servers distributed globally, designed to deliver content, including images, more efficiently to users based on their geographic location. Here’s how CDNs Optimise image delivery:

Reduced Latency: By storing copies of your images on multiple servers around the world, a CDN can serve images from the server closest to the user. This dramatically reduces the time it takes for images to reach the user, enhancing the speed and performance of your site.

Bandwidth Optimisation: CDNs can reduce the bandwidth consumed by image requests through techniques like compression and caching. This not only speeds up image delivery but also lowers hosting costs.

Improved Availability and Scalability: CDNs can handle spikes in traffic more effectively than a single server, ensuring your images are always available even during traffic surges. This scalability is crucial for maintaining performance during peak times.

Next-Gen Image Formats: AVIF and WebP

Next-generation image formats like AVIF and WebP offer superior compression and quality characteristics compared to traditional formats like JPEG and PNG. Here’s a closer look at these formats:

WebP: Developed by Google, WebP provides both lossy and lossless compression, often delivering smaller file sizes than JPEG, PNG, and GIF formats without sacrificing quality. It supports transparency and animation, making it a versatile choice for various types of web content. WebP is widely supported in modern browsers, making it an excellent option for improving loading times and performance.

AVIF (AV1 Image File Format): AVIF is a newer format that offers significant compression efficiency improvements over WebP. It is based on the AV1 video codec and supports a wide colour gamut, high dynamic range (HDR), and both lossy and lossless compression. While AVIF’s browser support is growing, it promises to further reduce image file sizes without compromising visual quality, making it an exciting option for future-proofing web content.

Advantages of Next-Gen Formats

Efficiency and Performance: Both WebP and AVIF offer better compression than older formats, meaning you can use higher quality images with smaller file sizes. This results in faster page load times and improved user experience.

Enhanced Visual Quality: These formats support a broader range of colours and finer gradations, making them ideal for high-quality photographs and images with rich visual details.

Future-Proofing: As browser support for these formats expands, adopting them early ensures your website remains at the forefront of web performance and user experience trends.

Incorporating CDNs and next-gen image formats into your image Optimisation strategy can significantly enhance your website’s loading speed, efficiency, and visual appeal. These advanced strategies are becoming increasingly important in a web ecosystem that values speed, quality, and user experience above all.

Common Mistakes to Avoid

While Optimising images can significantly enhance your website’s performance, there are common pitfalls that can undermine your efforts. Being aware of these mistakes can help you avoid them and ensure that your image Optimisation strategy is effective.

Overlooking Browser Caching Settings for Images

Browser caching is a mechanism that stores website resources on local computers when a user visits a webpage. When the user returns to the page, the browser can load the page without having to download those resources from the server again, which significantly reduces load times.

Mistake: Failing to configure or Optimise browser caching settings for images can lead to unnecessary re-fetching of images that haven’t changed, increasing load times for repeat visitors.

Solution: Ensure that your server is configured to provide optimal caching instructions for browsers. Set long cache lifetimes for images that change infrequently. Use versioning or fingerprinting for images that update regularly, so browsers can easily determine when to fetch a new version.

Using Too Many Images or Unnecessarily High-Resolution Images

Images enhance the visual appeal and engagement of a website. However, using too many images or images that are much larger than needed can drastically slow down your site.

Mistake: Overloading pages with images or not resizing and compressing images to their optimal display size.

Solution: Be judicious in your use of images. Use CSS and JavaScript for decorative elements where possible, and ensure that all images are appropriately resized and compressed. Consider the context in which the image will be viewed and scale the resolution accordingly.

Forgetting to Test Website Performance Before and After Optimisation

Testing is crucial to understand the impact of your Optimisation efforts and to identify areas for further improvement.

Mistake: Not measuring website performance both before and after making Optimisations, leading to a lack of understanding of the Optimisations’ effectiveness.

Solution: Use tools like Google’s PageSpeed Insights, GTmetrix, or WebPageTest to benchmark your website’s performance before starting your Optimisation efforts. After implementing Optimisations, test again to measure the impact. Regular testing can also help catch any new performance issues as your site evolves.

Avoiding these common mistakes can significantly enhance the effectiveness of your image Optimisation strategy. By properly configuring browser caching, being strategic about the number and size of images used, and regularly testing your website’s performance, you can ensure that your site remains fast, engaging, and competitive.

Real-World Impact Of Optimising Your Images

Image Optimisation can yield significant improvements in website performance. But it’s easy for me to say that, and not so easy for you to really envisage just how much doing this can improve the performance of your site.

So, here’s a real-world example from a client we worked with a couple of years ago. A company in the beverage industry, this client’s website was facing challenges with their performance, particularly in terms of loading speed, which is a critical factor for user experience and SEO. They had hundreds of products across the site, so naturally there were a huge number of images.

Before Image Optimisation

The client’s website initially displayed performance metrics that indicated significant room for improvement:

First Contentful Paint (FCP): With an FCP of over 4 seconds, the delay in loading visible content was far above the ideal threshold, potentially leading to user frustration and higher bounce rates.

Largest Contentful Paint (LCP): The LCP stood at nearly 5 seconds, which could severely impact the user’s experience by delaying the display of the most meaningful content on the page.

Speed Index: The Speed Index was recorded at 3.2 seconds, suggesting that the content visibility during page load was suboptimal. The Speed Index measures how quickly the contents are visually displayed during the loading process, and a lower index is generally indicative of a better user experience.

Total Blocking Time (TBT): The initial Total Blocking Time was 50 ms. This metric measures the total amount of time that a page is blocked from responding to user input, such as mouse clicks or screen taps.

After Image Optimisation

Following the implementation of image Optimisation strategies, the website’s performance metrics improved significantly:

First Contentful Paint (FCP): Improved dramatically to 1.6 seconds, suggesting that users now receive visual feedback much faster when they land on the site.

Largest Contentful Paint (LCP): Decreased to 2.6 seconds, greatly enhancing the user’s experience by making the main content of the page available much quicker than before.

Speed Index: The Speed Index saw a substantial improvement, dropping to 1.1 seconds. This indicates that the visual load of the site’s content became significantly faster, providing a better impression of the page’s speed to the user.

Total Blocking Time (TBT): The TBT was reduced to 0 ms, suggesting that the website is now more responsive to user interactions, with no delay that could potentially frustrate users or dissuade them from engaging with the site.

These improvements in key performance metrics reflect a highly Optimised website that not only enhances the user experience but also aligns with the best practices for Core Web Vitals. With the decrease in both Speed Index and Total Blocking Time, the client’s website is likely to see benefits in terms of user retention, engagement, and possibly SEO rankings due to better page speed.

Impact on Website Performance

After implementing image Optimisation strategies:

User Experience: The user experience was greatly enhanced due to content loading more swiftly, which likely contributed to a decrease in bounce rates and an increase in page views.

SEO Ranking: Faster load times helped improve the website’s SEO ranking, leading to better visibility in search engine results.

Mobile Performance: The client’s website became more accessible to mobile users who typically have more limited bandwidth, thereby improving engagement on mobile devices.

Through strategic image Optimisation, the client’s website performance metrics underwent a significant positive transformation. The improvements in FCP and LCP are indicative of an enhanced overall user experience, which is beneficial for maintaining a competitive edge in the digital marketplace. These results underscore the importance of regular performance audits and the implementation of image Optimisation techniques as part of a comprehensive website performance strategy.

Optimise Your Images For An Easy SEO Hack

Optimising images stands out as one of the simplest yet most effective steps in boosting website performance, offering a clear pathway to faster load times, enhanced user experience, and improved SEO outcomes. From choosing the right format and size to understanding compression techniques and utilising advanced tools, the benefits are well-documented and profound. 

If you’re looking for a proactive way to boost your website performance, that’s relatively simple to do, this is it. If you’ve not done it already, make it a top priority. Well optimised images will ensure your website not only captivates users with visual appeal but also delivers content swiftly and efficiently; an absolute must if you want to please the Google gods (not to mention your audience)!