png vs webp: which format should you use?
both png and webp support transparency, both produce high-quality images, and both are widely supported. so when should you actually use each one? here's the practical breakdown.
the fundamental difference
png uses lossless compression. its decoded pixel values are preserved without compression artifacts, although metadata or color-profile handling can still differ between tools.
webp supports both lossy and lossless compression. in lossless mode, it preserves decoded pixels; in lossy mode, it trades some image detail for a smaller file.
the choice between them often comes down to: do you need pixel-perfect accuracy, or do you need the smallest possible file size?
file size: how much smaller is webp really?
the difference can be substantial, but it is not consistent enough to predict from format names alone.
lossless webp vs png
Google reports that lossless webp files were 26% smaller than png in its test corpus. your result depends on the image and encoder, so compare the actual output rather than assuming a fixed saving.
lossy webp vs png
the comparison here isn't strictly like-for-like because png is lossless. converting a png photo to lossy webp can reduce the file substantially, but the result depends on its content and quality setting.
for large images like product photos, hero images, or blog post illustrations, smaller files can reduce transfer time and bandwidth use.
in our reproducible browser test, WEBP at 85% reduced a text-heavy PNG by 96%, but only reduced an already-small transparent PNG icon by 26%. the text graphic needs closer visual inspection because a large saving does not prove its sharp edges survived acceptably.
transparency support: a draw
both png and webp support full alpha channel transparency. this means both formats can handle partially transparent images, gradual fade effects, and complex cutouts with soft edges.
in practice, the transparency quality between the two formats is indistinguishable when webp is used in lossless mode. when using lossy webp with transparency, there can occasionally be very slight artifacts along the edges of transparent areas at lower quality settings, though this is rarely visible at 80% quality or above.
if your image uses transparency, this isn't a reason to stick with png. webp handles it well.
where png still wins
there are genuine use cases where png is the better choice, and it's worth knowing them.
source and working files. if you're saving an image you'll open and edit again, png's lossless nature means no degradation. every time you re-save a lossy format, you lose a tiny bit of quality. over multiple save cycles this adds up. keep working files as png (or psd, tiff, etc).
screenshots with text or ui elements. lossy compression introduces subtle artifacts around high-contrast edges, which is especially noticeable with text. a screenshot saved as png will always look crisper than lossy webp.
digital art with flat colors. illustrations with large areas of solid color sometimes compress better as png because lossless compression handles repeated identical pixels very efficiently. try both and compare.
maximum compatibility requirements. png has very broad support, including in older software. if you're unsure, check what the destination accepts.
where webp wins
website images in general. for anything going onto a public-facing website, webp produces smaller files than png for equivalent quality. faster loads, better seo.
photographs with transparency. if you need a photo with a transparent background, lossy webp can be much smaller than a png. compare edge detail around the cutout.
hero images and banners. large decorative images can benefit from lossy webp compression. test a few quality settings and inspect the result at its rendered size.
animation. webp supports animation like gif, and animated webp is dramatically more efficient than both animated gif and animated png.
browser and software support
png has been around since 1996 and is supported absolutely everywhere without exception. every browser, every operating system, every image editing tool, every cms.
webp is supported in all modern browsers: chrome, firefox, safari (2020+), edge, opera, samsung internet. the only gaps are internet explorer and very old mobile browsers that represent negligible traffic in 2026.
where webp has more friction is outside browsers. not all image editing apps support it natively, though most major ones do now. some older cms platforms and enterprise tools may not handle webp uploads. if you need your images to work beyond the web, png remains the safer choice.
the side-by-side comparison
| PNG | WEBP | |
|---|---|---|
| compression | lossless only | lossy + lossless |
| file size | larger | 26-80% smaller |
| transparency | yes (full alpha) | yes (full alpha) |
| animation | apng (limited support) | yes |
| browser support | very broad | current major browsers |
| software support | very broad | many current tools |
| best for | working files, screenshots | web publishing |
the practical workflow
the best approach for most people is to keep working files as png (or in your native app format), and test webp when you're ready to publish. this way you retain the original lossless version and can compare the real output before choosing it.
think of png as your archival format and webp as your delivery format. create and edit in png, publish in webp.
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