PNG vs WEBP: What's the Difference and Which Format Should You Use?

When building websites or preparing images for digital use, the format you choose matters more than most people realize. PNG and WEBP are both widely used image formats, but they serve very different purposes. Choose the wrong one and you could end up with unnecessarily large files that slow down your website and damage your Google rankings. In this guide, we break down every meaningful difference between PNG and WEBP — covering file size, image quality, transparency support, browser compatibility, and real-world use cases — so you can make the right decision every time.

What is PNG?

PNG (Portable Network Graphics) was introduced in the 1990s as an open-standard alternative to GIF. It uses lossless compression, meaning no image data is discarded during the process — every single pixel is preserved exactly as it was in the original. PNG supports full alpha channel transparency, which is why it's the standard choice for logos, icons, and web graphics that need a transparent background. PNG files are supported by virtually every browser, operating system, application, and design tool in existence. The main drawback is file size: PNG files tend to be considerably larger than other formats, particularly for photographic content or large images with complex color gradients.

What is WEBP?

WEBP is a modern image format developed by Google and officially released in 2010. Unlike PNG, which only supports lossless compression, WEBP supports both lossless and lossy compression within a single format. This flexibility lets you trade some quality for dramatically smaller file sizes (lossy), or maintain perfect pixel quality at still-smaller-than-PNG sizes (lossless). WEBP also supports full alpha channel transparency — meaning it can replace PNG for web use without sacrificing transparent backgrounds. Browser support has reached near-universal levels: Chrome, Firefox, Safari, Edge, and Opera all support WEBP natively, making it the preferred format for modern web development and image delivery.

PNG vs WEBP — Side by Side Comparison

When Should You Use PNG?

Use PNG when absolute lossless quality is non-negotiable. Logos that require crisp edges at any scale, screenshots of software interfaces, icons and graphics used in design workflows, or any image that will be further edited in Photoshop or Illustrator — these all benefit from PNG's lossless nature. PNG is also the correct choice when you need to share images with colleagues using older design software that may not yet support WEBP. If your image will be printed professionally or archived permanently, PNG guarantees nothing is ever lost. But for anything that lives exclusively on a website where speed matters, WEBP is the better option.

When Should You Use WEBP?

WEBP is the clear winner for anything that will be displayed on a website. Blog post images, hero banners, product photos on e-commerce stores, thumbnail images, background images — all of these benefit from WEBP's dramatically smaller file size. Smaller files mean faster page loads, which directly improves Google Core Web Vitals scores (particularly Largest Contentful Paint), reduces bounce rate, and improves organic SEO rankings. In 2025, virtually all modern browsers support WEBP, so there is no meaningful compatibility risk for web-facing images. If page speed and search rankings matter to you, WEBP is the right format for every image on your website.

Does Converting PNG to WEBP Reduce Quality?

The answer depends entirely on which type of WEBP compression you choose. WEBP offers two modes: lossless (zero quality reduction — the output is visually identical to the source PNG and still smaller in size) and lossy (some data is discarded in exchange for a much smaller file). For lossy WEBP, the quality slider controls how much data is removed. At 80–90% quality, the difference between a PNG and a WEBP is essentially invisible to the human eye. In blind tests, most viewers cannot reliably tell the two apart. At 85%, you typically get a file that is 60–75% smaller than the original PNG with no perceptible loss in sharpness, color accuracy, or detail. The Convertify quality slider gives you full control over this trade-off.

Final Verdict — PNG or WEBP?

The answer is straightforward: use WEBP for the web, PNG for everything else. Any image that goes onto a website — whether it's a blog post photo, an e-commerce product image, or a background — should be converted to WEBP. The file size savings alone (typically 60–75% smaller than the equivalent PNG) will meaningfully improve your PageSpeed scores and Core Web Vitals. Keep your original PNG files in your editing library for future edits, and serve WEBP to every visitor. Convertify makes this conversion free, instant, and completely private — with no file uploads and no sign-up required.