The short answer
For anything delivered through a browser or an app you control, WebP. For files you send to other people, attach to email, print, or upload to a form that lists accepted types, JPG. If you can serve both, serve WebP with a JPG fallback.
WebP vs JPG at a glance
| WebP | JPG | |
|---|---|---|
| Compression | Lossless: optional | Lossy |
| Transparency | Yes | No |
| Animation | Yes | No |
| Keeps EXIF in ConvertX | Yes | Yes |
| ConvertX reads it | Yes | Yes |
| ConvertX writes it | Yes | Yes |
| Extensions | .webp | .jpg, .jpeg |
WebP: Google's web format: about a third smaller than JPG, with optional transparency and lossless mode. JPG: The universal photo format. Small, lossy, opens everywhere, no transparency.
Choose WebP when
- Website and app images: 25–35 % smaller pages at no visible cost.
- Graphics with transparent backgrounds that must stay small.
- A large photo library you want to keep on a phone.
Choose JPG when
- Sharing with people whose software you don't control.
- Printing services, government forms, marketplaces and older CMSs.
- Devices and viewers made before about 2018.
File size
At the same visible quality, WebP photos are typically 25–35 % smaller than JPG. Lossless WebP is larger than JPG but exact.
Converting between them, offline
ConvertX converts on your device with no upload, in batches, and strips location data by default.
Frequently asked questions
Does WebP look worse than JPG?
At matched file sizes WebP looks better; at matched quality it is smaller. Both are lossy and both soften with aggressive settings.
Can every phone open WebP?
Every current Android and iOS version can. Problems appear in older desktop software and some email clients.
Should I convert my whole photo library to WebP?
Only if it stays on devices you control. Keep JPG or the camera original for anything you may share or print.