How to Compress a PNG Without Losing Quality

PNG has a reputation for producing large files, and for good reason: it's a lossless format, meaning it stores every pixel exactly as it is, with no data thrown away. That's great for quality but often means a simple screenshot or logo ends up several megabytes in size, far bigger than it needs to be for how it will actually be used.

The trick to compressing a PNG well is understanding that you're not really "compressing" a PNG at all in the traditional sense, you're converting it to a smarter format that achieves a similar look at a fraction of the size.

Why you can't just 'compress' a PNG directly

PNG's compression is lossless and largely fixed, there's no quality slider because there's no quality to trade away. Every pixel is preserved exactly. That's precisely why PNG files can be so large: unlike JPG, which can throw away detail the eye barely notices, PNG has to represent everything faithfully.

The practical way to shrink a large PNG, then, is to re-encode it into a format that does support a quality trade-off, most commonly WebP or JPG, while keeping the visual result close enough to the original that nobody notices the difference.

WebP: the best option for most PNGs

WebP is the modern choice for shrinking PNGs, for one key reason: it supports transparency, just like PNG does, but with far more efficient compression. A logo, icon, or screenshot with a transparent background can typically be converted to WebP at 90%+ quality and come out 60–90% smaller than the original PNG, with no visible difference at normal viewing sizes.

This makes WebP the default recommendation for anything that started life as a PNG because it needed transparency or sharp edges, screenshots, icons, logos, UI mockups. You keep the exact same visual behavior, just in a dramatically smaller file.

When JPG makes more sense instead

If the destination absolutely requires maximum compatibility, an older system, a print shop, or a platform that doesn't accept WebP, JPG is the fallback. The catch is that JPG doesn't support transparency at all, so any transparent areas in your PNG get filled with a solid background color you choose. For a photo-like PNG with no transparency, this is a fine option; for a logo with a transparent background, it usually isn't what you want.

A practical workflow

1. Start with your original PNG, don't compress a copy that's already been compressed once, since starting fresh gives the cleanest result.


2. Choose WebP as the output format if the image has transparency or will only be used digitally.


3. Set the quality to around 90% as a starting point, this typically preserves fine detail and text while still shrinking the file substantially.


4. Compare the before and after file sizes. If the saving isn't enough and the image quality still looks fine, try lowering the quality a bit further.


5. Only fall back to JPG if the destination specifically can't accept WebP.

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