If you’re building a website or just trying to shrink some images, you’ve probably seen WebP show up next to the familiar JPG. They both store photos, but they’re not interchangeable. Here’s how they actually differ and which one you should reach for.

Quick answer: Use WebP for images on websites you control — it’s 25–35% smaller than JPG at the same quality, so pages load faster. Use JPG anywhere you need guaranteed compatibility — email attachments, print shops, older software, or anyone you’re sending a file to directly.

What is WebP?

WebP is an image format Google released in 2010 specifically to make the web faster. It uses smarter compression than JPG, so a WebP image looks the same but downloads less data. It also does things JPG can’t:

  • Transparency (an alpha channel), like PNG
  • Both lossy and lossless modes in one format
  • Animation, like GIF but far smaller

How much smaller is WebP than JPG?

For a typical photo, WebP is usually 25–35% smaller than a JPG of equivalent quality. On an image-heavy page, that can shave meaningful time off load speed and improve your Core Web Vitals scores — which Google factors into search rankings. That’s the whole reason WebP exists.

So why not use WebP everywhere?

Compatibility. JPG has been universally supported for over 30 years — every phone, camera, browser, editor, and print service reads it. WebP is supported by all modern browsers (Chrome, Firefox, Safari, and Edge since around 2020), but it can still trip up:

  • Older software and operating systems
  • Some print shops and photo labs
  • Apps and forms that only accept .jpg uploads
  • People you email a file to, who then can’t open it

JPG is the “it just works” format. WebP is the “faster, if the destination supports it” format.

Which should I choose?

A simple rule of thumb:

  • Publishing images on your own website? Use WebP. Faster pages, same quality. You can convert JPG to WebP here.
  • Sending a file to a person, a printer, or an older app? Use JPG. If you downloaded a WebP and something won’t accept it, convert WebP to JPG and you’re set.

Both conversions run entirely in your browser here, so your images are never uploaded anywhere.

A note on quality

Remember that both WebP (in lossy mode) and JPG are lossy — they discard some detail to save space. Converting back and forth repeatedly will slowly degrade an image, since each save compresses again. Keep an original (or a lossless PNG) if you plan to edit, and only export to WebP or JPG as the final step.