PNG vs JPG: what's the difference, and when should you use each?
PNG and JPG are the two most common image formats, and choosing between them trips up almost everyone at some point. Save the wrong one and your file is either needlessly enormous or noticeably fuzzy. The good news is that once you understand the one core difference between them, the choice becomes obvious nearly every time. Here's the difference, the simple rule that follows from it, and the two classic mistakes to avoid.
The one difference that explains everything
JPG and PNG compress images in fundamentally different ways, and that single distinction drives everything else.
JPG is "lossy." To make files small, it throws away some image information — details your eye is unlikely to notice. This works brilliantly for photographs, where there's so much subtle variation that discarding a little is invisible. The payoff is dramatically smaller files.
PNG is "lossless." It preserves every single pixel exactly as it was, throwing nothing away. That makes it perfect for images that must stay crisp — but it also makes it much larger for complex images, because it isn't cutting any corners to save space.
The short version: JPG trades a little quality for much smaller files. PNG keeps perfect quality but produces larger files. Everything else follows from that.
The simple rule
Because of that difference, there's a rule that gets it right the vast majority of the time:
- Use JPG for photographs — anything from a camera or phone, with natural detail and gradients. JPG shrinks these enormously with no visible loss.
- Use PNG for graphics — logos, icons, screenshots, diagrams, illustrations, and anything containing text, sharp edges, flat colour, or transparency. PNG keeps these pin-sharp.
Photographs to JPG, everything computer-made to PNG. That one sentence covers most situations you'll meet.
The one thing only PNG can do: transparency
There's a hard functional difference beyond quality and size: PNG supports transparency and JPG does not. If you need an image with a transparent background — a logo that sits cleanly on top of a coloured page, say — it has to be PNG (or WebP, more on that below). Save that logo as JPG and the transparent areas fill in with solid white. This alone decides the format in a lot of design work.
| JPG | PNG | |
|---|---|---|
| Compression | Lossy (discards some detail) | Lossless (keeps everything) |
| Best for | Photographs | Graphics, logos, screenshots, text |
| File size | Small | Small for simple graphics, very large for photos |
| Transparency | No | Yes |
| Quality on edges/text | Can look fuzzy | Perfectly sharp |
The two classic mistakes
Almost all format regret comes down to one of these two, and they're mirror images of each other.
Saving a photo as PNG. The photo looks fine, but the file is huge — often five to ten times larger than it needs to be. This is why a screenshot of a photograph, or a photo exported as PNG, can be several megabytes when a JPG would be a few hundred kilobytes. If a photo's file size seems absurd, it's very often a PNG that should be a JPG.
Saving a logo, screenshot, or text image as JPG. Here JPG's lossy compression works against you: it smears the crisp edges of text and flat colour, leaving faint fuzzy halos around letters and lines. The file might be small, but it looks slightly dirty. Those should be PNG, which keeps every edge razor-sharp.
Converting between them
Knowing the rule, converting is easy. Got a photo that's a bloated PNG? Convert it to JPG and watch the file size collapse with no visible difference. Got a JPG logo with ugly fuzz around the text, or one you need to place on a transparent background? Converting to PNG restores sharpness (though it can't undo compression that already happened, so start from the best original you have).
One note when converting a PNG to JPG: because JPG has no transparency, any transparent areas have to be filled with a solid colour — usually white. That's expected, not a bug; it's simply JPG doing what JPG does.
Convert between PNG and JPG
Both run entirely in your browser — your images are never uploaded to a server.
Where WebP fits in
If you've been handed a third option and wondered where it belongs: WebP is a newer format designed to beat both. It can do lossy compression like JPG and lossless with transparency like PNG, and it's typically 25–35% smaller than either at similar quality. On paper it's the best of both worlds, and it's excellent for websites, where smaller files mean faster pages.
The catch is the familiar one: compatibility. WebP works in every current browser, but some older software and a few upload forms still don't accept it — which is exactly why people often need to convert a WebP back to JPG after saving one from the web. So WebP is a great choice when you control where the image is used (like your own website), and a riskier one when you're sending a file to someone whose software you can't predict. When in doubt for sharing, JPG remains the safest currency.
The bottom line
Remember the one difference and the rest is easy: JPG discards a little to make photos small; PNG keeps everything, which is perfect for graphics and essential for transparency. Photos go to JPG, computer-made images go to PNG, and WebP is a smart modern option when you control where the image will be used. Match the format to the job and you'll never end up with a bloated screenshot or a fuzzy logo again.