If you’ve spent any time optimising a website, you’ve probably heard someone mention WebP. It’s not a buzzword — it’s a genuinely better way to handle images on the web, and the evidence behind that claim is hard to argue with. WebP has steadily replaced JPEG and PNG as the preferred image format for developers, designers, and site owners who care about performance, and understanding why can make a real difference to how your website looks and loads.
What Exactly Is WebP?
WebP is an image format developed by Google, first introduced in 2010 and built specifically for the modern web. Unlike JPEG and PNG, which were designed decades earlier for different use cases, WebP was engineered from the ground up with web performance in mind.
The format supports both lossy and lossless compression, transparency (like PNG), and even animation (like GIF). That flexibility means it can replace multiple formats simultaneously without forcing developers to choose between quality and functionality.
Google developed it based on technology from the VP8 video codec. That foundation is part of what makes its compression so efficient — it borrows techniques from video encoding that older image formats simply weren’t designed to use.
The Numbers: How Much Smaller Are WebP Files?
This is where the case for WebP becomes concrete. According to Google’s own benchmarks, WebP images are:
- 25–34% smaller than JPEG at equivalent visual quality (lossy compression)
- 26% smaller than PNG on average (lossless compression)
These aren’t marginal improvements. On a page with 20 or 30 images — which is common for e-commerce sites or photography portfolios — that difference in file size translates directly into faster load times.
To put it in practical terms: if your product page currently loads 3MB worth of images in JPEG format, switching to WebP could bring that figure closer to 2MB without any visible change in quality. For mobile users on slower connections, that gap matters enormously.
Why JPEG and PNG Still Have Limitations
JPEG’s Compression Artefacts
JPEG has been the dominant lossy format since the 1990s, and it’s still widely used. But it comes with a well-known problem: artefacts. When you compress a JPEG too heavily, you start to see blocky distortions around sharp edges and fine details — that characteristic "muddy" look in areas of high contrast.
WebP’s lossy compression handles these transitions more gracefully. The visual degradation at equivalent compression ratios is noticeably less severe.
PNG’s File Size Problem
PNG solved the artefact problem by using lossless compression. What you put in is exactly what you get out. But the trade-off is file size — PNG images can be significantly larger than their JPEG counterparts, especially for photographs or complex graphics.
For transparency-heavy designs or icons, PNG made sense for years. Now WebP lossless handles transparency just as well, at a fraction of the size.
WebP and Website Performance: A Direct Connection
Page speed isn’t just a user experience issue — it has real consequences for search rankings and conversion rates. Google has made page speed a ranking signal, and its own Core Web Vitals framework includes metrics like Largest Contentful Paint (LCP), which is directly influenced by how quickly images load.
The Impact on Core Web Vitals
LCP measures how long it takes for the largest visible element on the page to load. For most pages, that element is an image. Reducing image file size through WebP directly improves LCP scores, which in turn improves your Core Web Vitals performance.
Google’s PageSpeed Insights tool will often flag JPEG and PNG images as opportunities for improvement and explicitly recommend serving images in next-generation formats — WebP being the primary recommendation.
Real-World Load Time Differences
A study by web performance consultancy Cloudinary found that switching to WebP reduced total image payload on test pages by an average of 30%. For a site receiving thousands of visitors per day, that reduction has compounding benefits: lower bandwidth costs, faster rendering times, and improved engagement metrics.
Browser Support: Is WebP Actually Safe to Use?
One of the historic objections to WebP was browser compatibility. In the early years, Safari didn’t support it. That’s no longer the case.
As of 2024, WebP is supported by all major browsers, including:
- Chrome (full support since 2014)
- Firefox (full support since 2019)
- Safari (full support since version 14, released in 2020)
- Edge and Opera
Global browser support for WebP now sits above 95% according to the Can I Use database. For most websites, that’s effectively universal coverage.
For the remaining edge cases — older browsers or specific enterprise environments — it’s still straightforward to implement a fallback using the HTML <picture> element, serving JPEG or PNG to browsers that don’t support WebP.
How to Start Using WebP
Converting Existing Images
You don’t need to reshoot or recreate your image library to start using WebP. Most image editors and conversion tools can handle the switch:
- Photoshop supports WebP natively (as of version 23.2)
- GIMP can export to WebP
- Squoosh (a free browser-based tool from Google) lets you compare quality and file size side by side before converting
- ImageMagick handles batch conversion via command line
- Cloudflare’s Image Optimisation and similar CDN services can automatically serve WebP to supported browsers
Implementing WebP on Your Website
The <picture> element is the cleanest way to serve WebP with a fallback:
This approach gives WebP-compatible browsers the optimised file while older browsers quietly fall back to JPEG. It requires no JavaScript and has no performance penalty.
If you’re using a CMS like WordPress, plugins such as Imagify, ShortPixel, or WebP Express can automate the conversion and delivery process without touching a single line of code.
WebP for E-Commerce and High-Traffic Sites
For e-commerce businesses, image performance isn’t an abstract technical concern — it’s a commercial one. Research from Google found that as page load time increases from one second to three seconds, the probability of a mobile visitor bouncing increases by 32%. Images are typically the largest contributors to page weight.
Retailers with large product catalogues — sometimes hundreds or thousands of individual product images — stand to gain the most from a systematic switch to WebP. Each image becomes a small performance win, and collectively those wins compound.
Platforms like Shopify, WooCommerce, and BigCommerce have progressively improved their native support for WebP, and many now serve it by default or offer it as a configurable option.
A Note on AVIF: The Format Beyond WebP
It’s worth mentioning that WebP isn’t the final word in image compression. AVIF, a newer format based on the AV1 codec, can compress images even more efficiently than WebP — sometimes by 20–50% at equivalent quality.
However, AVIF is still building out its browser support and tooling ecosystem. For most teams and most projects right now, WebP offers the better balance of compression performance, compatibility, and ease of implementation.
Think of it this way: WebP is the practical choice today. AVIF is worth watching for tomorrow.
Frequently Asked Questions
What is WebP and how is it different from JPEG or PNG?
WebP is a modern image format created by Google that supports both lossy and lossless compression, as well as transparency and animation. Unlike JPEG (which only does lossy) or PNG (which only does lossless), WebP handles all of these in a single format while producing smaller files.
Will switching to WebP affect my image quality?
Not in any visible way for most use cases. At equivalent compression settings, WebP produces noticeably cleaner results than JPEG and files that are significantly smaller than PNG — without the kind of quality loss that would be obvious to the average viewer.
Is it difficult to convert my existing images to WebP?
No. Free tools like Google’s Squoosh make it easy to convert individual images, and CMS plugins automate the process for entire websites. Most modern image editors also support WebP export natively.
Do all browsers support WebP now?
Yes, for all practical purposes. WebP is supported by Chrome, Firefox, Safari, Edge, and Opera, covering more than 95% of global browser usage. Fallback solutions for older browsers are straightforward to implement using the HTML <picture> element.
Is WebP worth the effort if my site only has a few images?
Even for smaller sites, the benefits extend beyond just load time — better Core Web Vitals scores can improve your search rankings, and serving lighter pages improves the experience for mobile users with limited data plans. The conversion process is low-effort enough that there’s rarely a reason not to make the switch.
Conclusion
WebP isn’t a trend — it’s a practical improvement on formats that were built for a different era of the web. Smaller file sizes, better compression quality, broad browser support, and direct benefits to page speed make it the sensible default choice for anyone building or maintaining a website today.
The shift away from JPEG and PNG doesn’t have to be dramatic or disruptive. Start with new images, use existing tools to convert what’s already there, and implement a proper fallback for older browsers. The performance gains are real, measurable, and cumulative.
Ready to Improve Your Website’s Performance?
If you’d like to talk through how image optimisation or web performance improvements could benefit your specific site, our team is happy to help. Whether you’re starting from scratch or looking to optimise an existing setup, we can walk you through the practical steps.
Get in touch today — email us at moc.ssobebolg@ofni or call +353 1 868 2345. We’ll answer your questions and help you figure out the best approach for your needs.
