How JPG, PNG and WebP compress differently
JPG discards detail the eye is bad at noticing, working in 8 by 8 pixel blocks. That is why it is small, and why hard edges can pick up fuzzy halos. PNG keeps every pixel exactly and compresses the way a zip file does, so it is lossless and usually large for photos. WebP supports both approaches, plus transparency.
| Attribute | JPG | PNG | WebP |
|---|---|---|---|
| Compression | Lossy | Lossless | Lossy or lossless |
| Transparency | No | Yes | Yes |
| Best for | Photos | Screenshots, logos, text | Photos and graphics on the web |
| Support | Everywhere | Everywhere | All current browsers, some older apps |
When JPG is the right choice
JPG opens in practically everything: email clients, print shops, old phones, upload forms. For a photo whose destination you do not control, that reach matters more than the last few percent of file size.
The trade-off is that every save re-compresses the picture, so keep an original and export a new copy each time.
When PNG is worth the file size
A screenshot of text saved as JPG shows ringing around the letters. Saved as PNG, it stays sharp, and it is often small too, because flat areas of color compress very well.
PNG is also the choice when you need a transparent background, for example a logo you will place over other images. The same rule works in reverse: a photo saved as PNG is commonly several times larger than the JPG, with no visible gain.
When WebP beats both
Google's published comparison found lossy WebP 25 to 34 percent smaller than JPEG at equal visual quality, and lossless WebP about 26 percent smaller than PNG. That saving adds up on a page with many images.
The catch is compatibility. Current browsers display WebP, but some older apps, email tools and upload forms reject it. If a site refuses your file, convert it to JPG.
What happens when you convert between formats
Converting does not restore detail. JPG to PNG gives you a bigger file with the same artifacts, because PNG only prevents further loss. PNG to JPG has a different catch: JPG cannot be transparent, so transparent areas get filled with a solid color. PixDazzle's converters fill with white by default and let you pick another color.
Convert from the best copy you have
If you still have the original camera file or the source PNG, convert from that, not from a file that has already been compressed once.
