Understanding Image Compression Techniques
Why are some websites filled with crisp visuals that load faster than you can blink, while others leave us feeling like we’re stuck in the days of dial-up. It seems like there’s some magic at play, but there’s a less mystical explanation at hand. Image compression is an often overlooked hero behind seamless web experiences, and its techniques can feel more art than science.
Some believe that images have to lose quality if you want them to load faster. But it’s not quite so simple - and most importantly, it doesn’t have to be so brutal. Image compression revolves around clever methods of reducing file sizes without severely sacrificing what makes a picture ‘pop’.
In fact, a few minor technical tweaks and file format changes can have a fairly significant impact on image clarity and performance. Sort of. It’s all about deciding which compression method best serves your purpose, balancing the imperceptible dip in quality with the fast loading times that make users want to browse longer.
More or less. Lossy and lossless compression are the big buzzwords here. More or less. It isn’t as self-explanatory as it appears.
Lossless compression preserves every little detail from the original photo - which can be helpful for high-res product images or logos where every bit matters. Sort of. You get the same detailed image as what you put in, but with smaller file sizes thanks to some clever data encoding. Lossy compression does what it says on the tin - irreversibly shrinks your images by removing data beyond what the eye might see (or at least notice on first glance).
Sometimes you might get away with a slightly blurry image to make your website load like a dream. Other times, that lost detail could affect functionality - like losing those droplets on a shampoo bottle or losing text in an infographic. Choosing wisely between lossy and lossless isn’t always straightforward, but being aware of their effects on your site’s bandwidth is fairly vital to making sense of each technique’s pros and cons.
More or less. Most sites lean into lossy for hero images or placeholder pictures, or lossless for highly interactive media that needs more clarity or transparency. With third-party plugins and media management tools getting smarter by the day, much of this work can now happen behind the scenes for sites that can afford their services. But no plugin or AI automation can do much without human oversight from someone who understands image optimisation basics quite well.
Knowing your trade-offs is half the battle won when it comes to helping people access great content fast, no matter what device they’re on or how patchy their internet connection might be.
Choosing the Right File Formats
Do you remember the last time you uploaded an image file and saw it look a bit odd. Or perhaps it ended up pixelated or compressed. The way I see it, for those of us who want a crisp image that is nearly always quick to load, choosing the right file format is so important. There are several common types of file formats that come to mind - JPG (or JPEG), GIF, PNG, SVG, and WEBP.
These are all lossy compression formats - meaning that they lose some part of their data in compression and cannot be reverted back to the original form. JPGs are usually used for images with lots of colours and complex gradients, and are sometimes not a great option for simplistic graphic design images as they end up getting too compressed. PNGs can compress images but do so in a lossless way so they’re ideal for graphic design elements, as well as images with text over them. However, PNGs do take up a lot of storage space because of their lossless compression.
GIFs are nearly always best for simple animated images but cannot be used for photos or complicated graphics. These files can create animation effects but need to be used sparingly unless your page ends up looking like a B-grade movie streaming site. SVGs work best with icons and logos.
And finally, WEBP is fairly new but very trendy when it comes to modern website design - it offers lossy or lossless compression while providing better quality than JPEG or PNG without drastically increasing file size. It’s important to know that there are several more file formats out there, including PSD, TIFF, AI, EPS, APNG and more. Knowing the difference between all the different file formats isn’t just good cocktail party trivia (although they might be) – they could help you increase your site speed and help you make sure your content looks exactly how you want it to.
Responsive Images for Different Devices
Ever wondered why the same website looks different on your phone, tablet, or laptop. You can seldom thank responsive images for that. They’re those clever bits of code that automatically change size, quality, or even file format based on your device.
Not only does this make everything look better, but it also makes the site faster to load. Sort of. That means you don’t have to deal with fuzzy photos or wait for hours to look at one good picture. Most people use multiple devices in a day to browse the internet.
Responsive images help make sure their experience is not disappointing. This often involves creating images in different sizes and then adding code to automatically display the most appropriate one for your screen. The idea is to avoid making phones download massive files meant for desktops while also not showing tiny pictures on larger screens.
It makes a difference even if you don’t notice it right away. The best part is presumably that it’s not all that hard to implement responsive images.
The main thing is that it should be done at the start of building a website because making these changes after can take a lot of time and effort. It’s also great for SEO since mobile browsing has long overtaken desktop usage and search engines tend to penalise websites that don’t follow mobile-first practices. In general, using responsive images is about putting your users first and offering them an experience they want to return to. No matter how many new devices come out or how often phones get bigger or smaller, your images will be ready for them all.
This will be invaluable for growing your business since things are only going to get more complicated as time goes on.
Implementing Lazy Loading for Enhanced Performance
Ever found yourself stuck on a website waiting for what feels like hours as images slowly appear one after another. Loading time is such an under-recognised but massively important part of the user experience. When you’ve poured your heart and soul into a beautifully designed website, every second spent waiting for it to come alive is agony.
Lazy loading seems a little counter-intuitive to those of us who want everything at once, but it enhances performance in ways few other image optimisation solutions can. Lazy loading involves the delayed loading of images on a website until they are actually needed. That means there’s no rush to load in visuals until they’re visible on the user’s screen, and nothing distracting or interruptive happens while the page loads either. Lazy loading offers more than just reduced loading times - there’s a couple dozen benefits to lazy loading from SEO ranking to efficiency improvements.
More or less. It’s as easy as checking off some boxes if you happen to use Shopify or BigCommerce, but there are plug-ins available for all sorts of different platforms. If you’re one of those overachievers who hand-codes their websites, lazy loading can still be implemented simply by using HTML and JavaScript.
The inbuilt “lazy” attribute can be added when an image is first placed on a web page by using: . There are more advanced solutions too that take laziness and make it smart by accounting for high-traffic periods in the day or prioritising higher quality visuals throughout certain sections.
Making use of this type of loading can make all the difference between getting lost in endless search results and standing out as an engaging experience worth remembering. While Google still considers user experience relevant to SEO rankings, faster-loading times will help boost your site up those rankings and get you onto an ‘explore’ page where you’ll find half your target audience these days anyway. If you’re running an e-commerce store or are simply trying to build up your portfolio, then staying performance-forward with lazy loading is absolutely crucial right now.
Leveraging Content Delivery Networks (CDNs)
Where is your website hosted, and does that location matter. The answer is yes, sort of. As a general rule, the farther your content physically is from your users, the slower it will load.
If you’re aiming to deliver video or high-resolution images across different cities, countries and continents, this is where content delivery networks (CDNs) can be helpful. A CDN hosts assets like images and videos on multiple servers in many locations globally. So when someone lands on your website in London while you’re based in Sydney, for example, they’re receiving content from a nearby server rather than from yours halfway across the world.
This means faster loading times for your website regardless of where your visitors are nearly always based - and more seamless viewing experiences for everybody. The other interesting thing about a CDN is that it distributes high-resolution image files without losing quality - so you don’t need to worry about pixelation with compression.
Some popular CDNs today include Amazon Web Services (AWS), Microsoft Azure, Google Cloud CDN and Rackspace. More or less. If you’re running an online store or working with a website developer or designer to build your portfolio or business website, CDNs can be useful additions to image optimisation software as another way of making sure everything loads quickly.
I’ll admit not everybody needs to use one - especially if you have a small site with mostly text-based content. But when used in conjunction with image compression tools, lazy loading plugins and browser caching strategies they can be reliable additions to any speed optimisation strategy for more engaging visuals.
Best Practices for Image Dimensions and Resolutions
Seems Like what do you reckon the difference is between image size and resolution. In my experience, most people don’t get it quite right. Image dimensions refer to width and height, while resolution is all about how many pixels are packed into that space.
If you’re looking to up your image optimisation game, these two things are more or less a great starting point. Let’s start with dimensions. Sort of.
When uploading images to your website, you want to make sure they fit perfectly into their containers, otherwise browsers will have to resize them which can slow your site down and affect performance. Find out the exact size you want your images to display at and upload them in that exact size - this way they’ll load much quicker. It’s all about reducing the number of pixels being loaded on a page. When it comes to resolution, remember that anything over 72 dpi is not doing your site any favours.
Higher resolution means higher quality but also means higher file sizes which can possibly slow down loading speeds significantly. Sure, higher resolutions work for print images, but when it comes to web images you want a lower file size without sacrificing too much on quality.
If you’re someone who uses WordPress or similar CMS platforms, plugins can help automate this process but I always think manual resizing is best because it gives me more control over what’s being displayed on my website - but if automation works for you then by all means use it. The main thing is finding out what works best for you - ultimately this means making sure those pesky images aren’t affecting loading speeds or performance in any way possible so visitors don’t bounce away before even seeing what great content awaits them.