What is the difference between JPG and PNG?
JPG (also written JPEG) uses lossy compression — it permanently discards some image data to achieve smaller file sizes. This makes JPG excellent for photographs where subtle quality loss is acceptable. PNG uses lossless compression — it preserves every single pixel of data exactly. PNG also supports full alpha transparency, which JPG does not. The tradeoff is that PNG files are significantly larger than JPG for photographic content, but they're ideal for graphics, logos, screenshots, and any image where precise colours and sharp edges matter.
When should I convert JPG to PNG?
Convert JPG to PNG when you need to edit an image multiple times without accumulating quality loss, when you need transparency in your image, when you're working with screenshots or UI graphics where sharp text and edges matter, or when you need to pass an image to a design tool that works better with lossless formats. Note that converting JPG to PNG will not recover any quality already lost during original JPG compression — it simply prevents any further loss going forward.