TL;DR: In the WebP vs PNG debate, WebP usually wins on file size: Google says lossless WebP files are about 26% smaller than PNGs, and WebP can also do lossy compression, transparency and animation. PNG is the safer pick for maximum compatibility, editing workflows, archiving and print hand-offs, because practically every app opens it. For most websites, serve WebP and keep a PNG master.
WebP vs PNG is one of the most common choices you face when saving graphics for the web. Both formats support transparency and both can be lossless, so it is not obvious which one to choose. This guide compares them side by side, explains when each format makes sense, and shows how to convert between them without losing quality.
What is PNG?
PNG (Portable Network Graphics) is a raster image format created in the mid-1990s as an open, patent-free alternative to GIF. It is published as a W3C specification. PNG compresses images losslessly, which means every pixel is preserved exactly. It supports full color and an alpha channel for smooth transparency.
That makes PNG a favorite for screenshots, user-interface graphics, logos exported as images, diagrams and anything with sharp edges or text. The trade-off is size: for photographs, PNG files are often much larger than lossy formats. If you are comparing PNG with JPG for photos, see our PNG vs JPG guide.
What is WebP?
WebP is an image format developed by Google that supports both lossy and lossless compression, alpha transparency and animation. According to Google’s WebP FAQ, WebP typically achieves about 30% more compression than JPEG without a loss of image quality, and WebP lossless images are 26% smaller than PNGs. Those figures come from Google’s own studies, so your results will vary by image.
WebP’s lossy mode is based on the VP8 video codec, while its lossless mode uses a separate encoder designed for graphics. A single WebP file can be up to 16,383 x 16,383 pixels, per Google’s documentation.
WebP vs PNG: side-by-side comparison
| Feature | WebP | PNG |
|---|---|---|
| Compression | Lossy or lossless | Lossless only |
| Typical file size | Smaller (Google cites ~26% smaller lossless) | Larger, especially for photos |
| Transparency | Yes (8-bit alpha, also in lossy mode) | Yes (full alpha) |
| Animation | Yes | Not in standard PNG (APNG is a separate extension) |
| Browser support | All major modern browsers | Universal |
| Software support | Good and growing, but not every older tool | Practically every editor, OS and app |
| Best for | Web delivery of photos and graphics | Masters, screenshots, editing, archiving |
The key differences explained
File size and page speed
Smaller images load faster, and image weight is one of the biggest factors in page speed. Because WebP can be lossless or lossy, you can often shrink a transparent PNG dramatically by switching to lossy WebP with alpha, something PNG cannot do at all. For a flat graphic with few colors, the gap may be small; for a photo with transparency, it can be large.
Quality
Lossless WebP and PNG both preserve every pixel, so quality is identical in that mode. In lossy mode, WebP discards some detail. At sensible quality settings that is hard to see, but text and fine lines can show artifacts if you compress too hard. Google’s FAQ also warns that converting a low-color PNG to lossy WebP can sometimes produce a larger file, so test both modes.
Compatibility
Google lists WebP support in Chrome, Edge, Firefox, Opera and Safari 14 or later (iOS 14 and macOS Big Sur onward). That covers nearly all current web visitors. PNG’s advantage is outside the browser: email clients, office documents, older design software and print shops all accept PNG without a second thought.
Editing and workflow
PNG is a better working format. It is lossless by definition, so you can re-save it repeatedly without degradation. Many teams keep PNG (or the original design file) as the master and export WebP only for publishing.
When to use WebP
- Photos and hero images on websites and blogs.
- Product images that need transparent backgrounds but should load fast.
- Replacing animated GIFs; Google says animated GIFs converted to lossy WebP are 64% smaller on average.
- Any page where Core Web Vitals and mobile speed matter.
When to use PNG
- Screenshots and UI mockups you will edit again.
- Files you send to clients, printers or people using older software.
- Archival masters where you want guaranteed lossless quality.
- Simple logos and icons when a vector isn’t available. If you can, use SVG instead; our SVG vs PNG guide explains why.
How to convert PNG to WebP (and back)
- Command line: Google’s free
cwebptool converts files, for examplecwebp -lossless image.png -o image.webpfor a lossless copy, orcwebp -q 80 image.png -o image.webpfor lossy. The matchingdwebptool converts WebP back to PNG. See Google’s WebP usage guide. - Design apps: many current editors can export WebP directly. Check your app’s export menu.
- WordPress: WordPress has accepted WebP uploads since version 5.8, according to the WordPress core team, and many image-optimization plugins can create WebP versions automatically.
- Serve with a fallback: if you need to support very old browsers, use the HTML
<picture>element to offer WebP first and PNG as a fallback.
Common mistakes to avoid
- Converting a JPG to lossless WebP and expecting it to shrink; it usually grows.
- Deleting your PNG masters after converting.
- Using heavy lossy compression on images with small text.
- Forgetting to check color and transparency edges after conversion. For screen versus print color, see our RGB vs CMYK guide.
The bottom line on WebP vs PNG
For publishing images on the web, WebP is usually the better choice: smaller files, transparency, animation and wide browser support. PNG remains the best format for editing, sharing outside the browser and archiving. The practical workflow for most designers and site owners is simple: keep a PNG master, publish WebP. For more on resolution, read our DPI vs PPI explainer.
Sources
- Google for Developers: WebP Frequently Asked Questions
- Google for Developers: Using cwebp, dwebp and other WebP tools
- W3C: Portable Network Graphics (PNG) Specification
- Make WordPress Core: WordPress 5.8 adds WebP support
The Teck Hustlers Editorial Team covers technology, business, finance and gaming news for readers who want the story behind the headline. Every article is researched, written and edited by our in-house team, checked against company announcements, filings and reputable reporting, and updated when new facts emerge. We focus on what each development means for founders, professionals, investors and everyday users. Have a tip or a correction? Reach us through our contact page.
