Not all images are created equal. Choosing the right format – and keeping files lean – helps your pages look good and load fast. It’s a simple win for user experience and search rankings.
Before picking an image type, it helps to know if your image is vector‑based or raster‑based. Vector images are made from lines and shapes and scale perfectly at any size, which makes them ideal for logos, icons and simple illustrations. Raster images are made of pixels; they’re great for photos and detailed artwork, but if you enlarge them you’ll see blurring and jagged edges.
Classic formats: JPEG, PNG & GIF
JPEG (sometimes written .jpg) remains the workhorse for photographs and large backgrounds. It uses a lossy compression method to reduce file size, which makes it light and quick to load, but the trade‑off is some loss of detail and the fact it cannot handle transparency. Use JPEGs for things like hero images, blog photos and banners — but avoid using them for logos or text because the edges will look fuzzy and there’s no way to allow the background to show through.
PNG is the go‑to format for clear graphics and anything requiring transparency. Its lossless compression preserves details, so text and sharp lines remain crisp. The downside is that file sizes can be larger than JPEG, especially for complex images. Logos, icons and diagrams benefit most from PNG’s clarity. For photographs or full‑width backgrounds, save bandwidth by sticking to JPEG or a modern alternative.
GIF has largely fallen out of favour on websites except for simple animations or preloaders. It is limited to a palette of 256 colours, which keeps file sizes down but makes photos look blotchy. If you need a short, looping animation, consider using a small MP4 video instead — it compresses more efficiently and plays smoothly on modern browsers.
Modern options: SVG, WebP & AVIF
SVG stands for Scalable Vector Graphics. As a vector format it scales perfectly without losing sharpness and supports transparency, making it a great choice for logos, icons and simple illustrations. An SVG file is usually tiny because it only stores instructions for shapes rather than pixel data. If your artwork contains gradients or photo‑like detail, however, you may run into compatibility quirks on older browsers — stick to raster formats for those cases.
WebP is a next‑generation raster format created by Google. It supports both lossy and lossless compression, transparency and even simple animation. In practice a WebP file is around a quarter smaller than a comparable JPEG or PNG, which means pages load more quickly without any perceptible drop in quality. Nearly all modern browsers support WebP, and Safari has joined the club in recent releases. Because older browsers still lag behind, the safest approach is to provide a JPEG or PNG fallback using the <picture> element or a Joomla plugin that serves the right version automatically.
AVIF is another emerging format that offers even better compression than WebP. Support is growing but not yet universal. As with WebP, you can serve AVIF alongside a more widely supported format to cover all visitors. For now, most Joomla users will get the biggest benefit from moving photos and graphics to WebP while monitoring AVIF adoption.
How to use WebP in Joomla
Joomla’s built‑in media manager can accept WebP files if you add webp to the list of allowed extensions. The downside is that it cannot generate a preview, so you’ll only see a file name. When inserting images into an article, you can wrap them in a <picture> tag to serve WebP to supported browsers and fall back to JPEG or PNG for others. A typical snippet looks like this:
<picture> <source srcset="/path/to/image.webp" type="image/webp" /> <img src="/path/to/image.jpg" alt="Alternative description" width="600" height="400" /> </picture>If writing HTML isn’t your thing, you can let extensions do the heavy lifting. Plugins like DJ WebP convert uploaded JPEG and PNG files into WebP on the fly and serve the right version based on the visitor’s browser. SP Page Builder has native WebP support — just enable WebP in your server’s GD library, upload the WebP file in place of a PNG or JPEG and the addon takes care of the rest. Aimy Speed Optimization is another handy plugin that offers lazy loading and caching for WebP images to squeeze out extra performance.
Practical guidelines for managing images
Keeping your media library under control isn’t just about choosing the right format. It’s about consistency and discipline. Here are some simple habits that make a big difference:
- Use descriptive names and folders – name files in lowercase with hyphens (for example
company-logo.webp) and organise them in folders (likeimages/blog/2025/) so you and your colleagues can find them easily. - Resize and compress before uploading – don’t upload a 4000 pixel photo if you only need 800 pixels on the page. Export at 72 dpi for web use and compress the file with a tool like TinyPNG or Squoosh to remove invisible data.
- Set size and type guidelines – if your team collaborates on content, agree on maximum file sizes, preferred formats and naming conventions. Just one rogue 5 MB image can drag down your whole page speed.
- Leverage lazy loading and caching – enable Joomla’s built‑in lazy loading or use an optimisation plugin to ensure images load only when they enter the viewport and are cached efficiently.
Our agency’s view
From our experience building and managing Joomla sites, switching to WebP is one of the easiest wins for performance. We still keep JPEGs and PNGs around as fallbacks, but for most photos and graphics the WebP version becomes the default.
What makes the biggest difference, though, is discipline 🙂: agreeing on naming conventions, compressing files before upload and auditing your media library regularly. A few giant files hidden deep in a folder can slow your site more than anything else.
Key takeaways
- Use vector formats like SVG for logos and icons.
- Choose JPEG for photos and backgrounds, PNG for graphics with transparency, and WebP for the best of both worlds.
- When serving WebP or AVIF, always provide a JPEG or PNG fallback.
- Set naming, size and compression guidelines for anyone who uploads images.
