Picking the wrong image format can make a page several times heavier than it needs to be.
PNG, WebP and JPG each win in different situations.
Here is how to choose in under a minute - and the details if you want them.
The quick answer
- Screenshots, logos, icons, text, sharp graphics - PNG (optimized), or lossless WebP on websites.
- Photos on a website - WebP, with JPG as the universal fallback.
- Photos you email, print or upload anywhere - JPG.
- Anything with a transparent background on a website - WebP, or PNG when the file must work everywhere.
PNG vs WebP vs JPG side by side
| Feature | PNG | WebP | JPG |
|---|---|---|---|
| Compression | Lossless | Lossless or lossy | Lossy |
| Transparency | Yes, full alpha | Yes, full alpha | No |
| Animation | APNG only | Yes | No |
| Photos | Very large files | Small | Small |
| Text and sharp edges | Pixel-perfect | Good (lossless mode) | Blurry halos |
| Browser support | Universal | All modern browsers | Universal |
| Support outside browsers | Universal | Good, still patchy in older apps | Universal |
| Re-saving | No quality loss | Loss in lossy mode | Loses quality every save |
When PNG wins
PNG never changes a pixel, so text, UI and line art stay razor sharp. It is also the format every editor, OS, CMS and upload form accepts.
Its weakness is size on complex images. Fix that by optimizing the PNG - typically 50-80% smaller while staying a PNG - or by using an 8-bit palette for flat graphics.
When WebP wins
WebP does almost everything PNG and JPG do, in fewer bytes. Lossless WebP is typically around a quarter smaller than PNG, and lossy WebP usually beats JPG at the same visual quality.
It is the best default for images on your own website. Keep a PNG or JPG master copy, though - some desktop apps, print shops and upload forms still reject WebP.
When JPG wins
JPG is still the most compatible way to share a photo. Every phone, camera, printer and email client handles it.
Avoid it for screenshots, text and logos: its compression smears sharp edges into visible halos. And never use it when you need transparency.
What about AVIF?
AVIF often compresses photos even better than WebP and supports transparency and HDR. All major browsers support it today.
The trade-offs are slower encoding and weaker support in desktop apps. For most sites, WebP with a JPG or PNG fallback is the simpler choice, with AVIF as an optional extra for large hero photos.
Image formats, page speed and SEO
Images are often the heaviest part of a page and frequently the Largest Contentful Paint element. Lighter images load sooner, which helps Core Web Vitals and keeps visitors around.
The biggest wins usually come from the right dimensions and a modern format, not from squeezing the last few percent out of quality settings. Serve the size you display, pick the right format, then compress.
Whatever the format, always set width and height attributes on your images. It prevents layout shift while they load.
How to convert between PNG, WebP and JPG
All of these are free and need no signup:
- Convert PNG to JPG, WebP or AVIF - with quality control and a background color for transparent areas.
- Convert WebP to PNG - for apps that will not open WebP.
- Convert JPG, GIF, BMP, TIFF or AVIF to PNG - when you need a lossless editable copy.
- Optimize a PNG - when the file has to stay PNG but needs to be smaller.
Still deciding how to shrink an image? Our guide on reducing PNG file size walks through every option.
Frequently Asked Questions
For websites, usually yes. Lossless WebP files are typically around a quarter smaller than the equivalent PNG, and lossy WebP with transparency can be far smaller still. PNG remains the safer choice for files you send to people, print, edit or upload to tools that may not accept WebP.
JPG (or WebP). Photos have millions of subtle color changes that lossless PNG stores at great cost - a photo as PNG is often 5-10x larger than a good-quality JPG that looks the same.
Yes. JPG has no alpha channel, so transparent areas are filled with a background color, usually white. Convert to WebP instead if you need to keep transparency with a smaller file.
Use the free WebP to PNG converter. It keeps transparency and works in batches, which is handy when a website or app hands you WebP files your editor will not open.