JPG, PNG, WebP or AVIF: which image format should you use?
Updated · 4 min read
Four formats cover almost every image you'll save or share today. Each one is the right answer somewhere and the wrong one somewhere else: a photo saved as PNG can be several times bigger than it needs to be, and a logo saved as JPG gets fuzzy edges and loses its transparent background. Here's how to choose.
Lossy and lossless, in one minute
Lossy formats throw away detail your eyes are unlikely to miss, in exchange for much smaller files. JPG is lossy; WebP and AVIF usually are, though both also have a lossless mode. Lossless formats keep every pixel exactly; PNG is the everyday example. Lossy suits photographs, where there's so much fine detail that small changes go unnoticed. Lossless suits screenshots, text, logos and diagrams, where lossy compression leaves visible smudges around sharp edges.
The second question is transparency — whether parts of the image can be see-through, like a logo placed on a coloured background. PNG, WebP and AVIF can store it. JPG can't: transparent areas have to be filled with a solid colour.
The four formats compared
| Format | Type | Transparency | Typical size | Opens in |
|---|---|---|---|---|
| JPG | Lossy | No | Small for photos | Practically everything |
| PNG | Lossless | Yes | Large for photos, compact for simple graphics | Practically everything |
| WebP | Lossy or lossless | Yes | Usually noticeably smaller than JPG | Every current browser; some older apps and editors don't |
| AVIF | Lossy or lossless | Yes | Often the smallest | Current major browsers; many desktop apps can't yet |
JPG
The universal photo format. Every phone, computer, printer and website reads it, and photos come out small. Its weaknesses: no transparency, blurry halos around text and sharp lines, and a little more detail lost every time a JPG is edited and saved again.
PNG
Lossless and transparent, which makes it the right choice for screenshots, interface graphics, logos, charts and anything with text. For photographs it's a poor fit: a photo saved as PNG is usually several times larger than the same photo as a JPG, with no difference you could see.
WebP
A modern web format from Google that does nearly everything: lossy or lossless, transparency, even animation. For photos it's usually noticeably smaller than JPG at a similar quality, and every current browser displays it. The catch is outside the browser — some older image viewers, editors and upload forms still don't accept it.
AVIF
The newest of the four, based on the AV1 video codec. It is often the smallest at a similar quality and handles transparency, and current versions of the major browsers display it. It's slower to create, and many desktop apps, older devices and forms can't open it yet — so it's best kept for websites that also have a fallback.
Which format for which job
| You're saving… | Use | Why |
|---|---|---|
| A photo to email, print or upload to a form | JPG | Opens everywhere and is accepted by almost every form |
| A screenshot, chart or image with text | PNG | Sharp edges stay sharp; nothing smudges |
| A logo or graphic with a transparent background | PNG (or WebP for the web) | Keeps transparency; JPG would fill it in |
| Photos for your own website | WebP or AVIF | Much smaller pages at the same look |
| An image someone will edit later | PNG | Lossless, so editing and re-saving doesn't add damage |
Tip: When a site or person doesn't say which format they want, send JPG for photos and PNG for everything else. Those two open everywhere.
Converting between formats
Image Converter changes up to 100 images at a time between JPG, PNG, WebP and AVIF, and can also write GIF, BMP and ICO icons. It reads HEIC and TIFF too. When you convert to JPG, transparent areas are filled with white by default (or black if you choose), so nothing turns into an unexpected black box. JPG, WebP and AVIF have a quality setting, 85% by default.
For the most common switches there are pages with the target format already set: PNG to JPG, JPG to PNG, WebP to JPG, JPG to WebP, PNG to WebP and AVIF to JPG.
Two things conversion can't do. It can't bring back detail: turning a small, blurry JPG into PNG gives you a bigger file with the same blur. And converting a photo to PNG "for quality" only makes it larger — the detail the JPG discarded is already gone.
Let your image decide
General rules are a good start, but every picture compresses differently — a flat illustration and a detailed landscape can rank the formats in a different order. Which Format Is Smallest? encodes one image as JPG and WebP at 80% quality, AVIF at 62% (which looks similar) and lossless PNG, then shows each size and lets you download the smallest. Images with transparency skip JPG, because it can't store it. Treat the result as a fair guide, not a lab measurement.
If you already know the format and just need a smaller file, Compress Image re-encodes JPG, PNG, WebP and AVIF at a quality you pick, or down to a size in KB. PNG savings there are modest because PNG is lossless — converting a photo from PNG to JPG or WebP usually saves far more.
Questions
Is WebP better than JPG?
For websites, usually: it's typically smaller at a similar quality and supports transparency. For email, printing and upload forms, JPG is still the safer choice because everything accepts it.
Why is my PNG so much bigger than the JPG?
PNG is lossless, so it stores every pixel of a photo exactly. That's ideal for screenshots and graphics but wasteful for photos — convert photos to JPG or WebP with Image Converter.
Does converting from JPG to PNG improve quality?
No. PNG keeps exactly what's in the JPG, including any compression artefacts, in a larger file. Convert to PNG only when you need lossless editing or transparency.