PNG vs WebP: Which Image Format Is Better for Your Website?

Images often make up the largest part of a web page’s total size. Picking the right format is one of the easiest ways to make a site load faster, rank better, and feel smoother for visitors. Two formats come up in this discussion more than any other: PNG and WebP.

This guide compares PNG vs WebP on file size, image quality, transparency, browser support, and SEO. It ends with clear advice on when to use each one.

Quick Answer: Is WebP Better Than PNG?

For most website images, yes. WebP is better than PNG. WebP files are usually much smaller than PNG files at the same visual quality. That means faster page loads and better Core Web Vitals scores. PNG is still the better choice for some cases: source files you plan to edit, images for email newsletters, and assets that must open in every piece of software.

What Is PNG?

PNG (Portable Network Graphics) was introduced in 1996 as an open replacement for GIF. It is a lossless format. When you compress it, no image data is thrown away, so the image looks exactly like the original.

Key features of PNG:

• Lossless compression
• Full alpha transparency, which gives smooth, soft edges
• Universal support in browsers, operating systems, design tools, and email clients
• Well suited to screenshots, logos, icons, and graphics with sharp lines or text

The main drawback: PNG files can get very large, especially for photos and detailed images.

What Is WebP?

WebP is an image format Google released in 2010, designed specifically for the web. It supports both lossy and lossless compression, and one format covers transparency and animation.

Key features of WebP:

• Lossy and lossless compression modes
• Alpha transparency, supported in both lossy and lossless modes
• Animation support, which can replace GIFs
• Much smaller file sizes than PNG and JPEG

According to Google’s own tests, lossless WebP images are around 26% smaller than PNGs, and lossy WebP images are 25–34% smaller than comparable JPEGs. When you use lossy WebP with transparency, the savings compared with PNG can be even bigger.

PNG vs WebP: Side-by-Side Comparison

Feature	PNG	WebP
Compression	Lossless only	Lossy and lossless
Typical file size	Large	Small (often 25–80% smaller)
Transparency	Yes	Yes (in both modes)
Animation	No (only APNG, a separate variant)	Yes
Browser support	Universal	All modern browsers
Email client support	Excellent	Inconsistent
Editing software support	Universal	Good and improving
Best for	Source files, editing, email, print prep	Website images, speed optimization

File Size: WebP Wins Clearly

File size is where the difference between PNG and WebP matters most. A detailed hero image saved as PNG might be 1–2 MB. The same image as lossy WebP can often come in under 200 KB with no difference most viewers would notice.

Smaller images mean:

• Faster page loads, especially on mobile data
• Lower bandwidth and hosting costs
• Better Largest Contentful Paint (LCP), which is one of Google’s Core Web Vitals

If your largest visible element is an image, switching from PNG to WebP is one of the quickest ways to improve LCP.

Image Quality: It Depends on the Mode

Lossless WebP vs PNG: Both keep every pixel exactly the same. Quality is identical, and WebP is simply smaller.

Lossy WebP vs PNG: Lossy WebP removes some data to save space. At a quality setting of around 75–85, most photos and illustrations look the same as the original to the human eye. Very sharp graphics, such as small text, thin lines, or pixel art, can show slight softness or artifacts at low quality settings. For those images, use lossless WebP or a higher quality setting.

Tip: Don’t guess. Export the image at a few quality levels, compare them at 100% zoom, and pick the smallest file that still looks clean.

Transparency: Both Handle It Well

PNG has long been the standard choice for transparent logos and icons. WebP supports the same full alpha transparency. Unlike PNG, it can also combine transparency with lossy compression. That makes WebP a strong choice for transparent product photos and overlays, where PNG files tend to be especially large.

Browser Support: No Longer a Problem

A few years ago, limited browser support was the main reason to avoid WebP. That is no longer true. Chrome, Edge, Firefox, Opera, and Safari (since version 14) all support WebP, which covers the vast majority of users worldwide.

If you still need to support very old browsers, you can serve a fallback with the HTML <picture> element:

<picture>
  <source srcset="image.webp" type="image/webp">
  <img src="image.png" alt="Descriptive alt text" width="800" height="600">
</picture>

Browsers that understand WebP load the smaller file. Everything else falls back to the PNG.

PNG vs WebP for SEO

Image format does not directly affect rankings. Google does not reward a file for being WebP. Format affects SEO indirectly through page speed and user experience:

1. Faster load times improve Core Web Vitals, which are part of Google’s page experience signals.
2. Lower bounce rates, because visitors are less likely to leave a fast page.
3. Better mobile performance, which matters under mobile-first indexing.
4. Tools like Google PageSpeed Insights flag PNG and JPEG images with the “Serve images in next-gen formats” suggestion.

Google Images indexes WebP without any problem, so switching formats won’t hurt your image search visibility. Keep the other image SEO basics in place too: descriptive file names, useful alt text, set width and height attributes, and lazy loading for images below the fold.

When to Use WebP

Choose WebP for:

• Blog images, hero banners, and featured images
• Product photos in online stores (WooCommerce, Shopify)
• Transparent images displayed on web pages
• Replacing animated GIFs
• Any site where speed and Core Web Vitals matter

When to Use PNG

Choose PNG for:

• Master and source files you’ll edit later, since lossless PNG is a safe archive format
• Email newsletters, because some email clients, including certain Outlook versions, don’t display WebP reliably
• Files you share with clients or print vendors who may use older software
• Detailed screenshots or diagrams where you want guaranteed pixel-perfect output and file size doesn’t matter much

How to Convert PNG to WebP

Online tools: Squoosh (by Google) lets you compare quality and file size side by side in the browser.

Command line: Google’s cwebp tool converts files in bulk:

cwebp -q 80 input.png -o output.webp

Design tools: Photoshop, Figma, and other modern editors can export directly to WebP.

WordPress: WordPress has supported WebP uploads since version 5.8. For existing media libraries, image optimization plugins can convert your PNG and JPEG files to WebP automatically and serve them with fallbacks. That way you don’t have to replace images one by one.

Shopify: Shopify’s CDN automatically serves WebP to supported browsers, even if you upload PNG or JPEG files.

Final Verdict: PNG vs WebP

For images displayed on websites, WebP is the better format in most cases. It gives you smaller files, transparency, and animation, with quality that matches PNG when you use lossless mode. PNG still has a clear role as a lossless source format and for email and wide software compatibility.

A practical workflow is to keep PNG as your master file and publish WebP on your website. You get the best of both: safe, editable originals and fast-loading pages.