Question 1

How do I know if quality loss is visible?

Accepted Answer

Compare on the slider. Look at small type, hair, and high-contrast edges. If those hold, the rest of the photo usually does.

Question 2

What does quality 80 apply to?

Accepted Answer

JPEG or WebP only. PNG uses a colour count from 2 to 256. For AVIF, compare on the slider instead of copying 80.

Question 3

Why keep the original JPEG sometimes?

Accepted Answer

When output is the same format and the re-encode is not smaller, the download is the original file. A format change always returns the new file.

Question 4

Does re-encoding remove EXIF?

Accepted Answer

Yes. A new encode strips GPS, camera model, and timestamps. A kept original still has them.

Question 5

Should I resize before dropping quality?

Accepted Answer

If the photo is wider than it will display, yes. Fewer pixels beat a harsh quality drop on a full-size camera file.

Question 6

What should I use for screenshots and UI?

Accepted Answer

Stay on PNG and lower the colour count. JPEG and WebP at 80 will smear sharp UI edges.

Question 7

Can I compare JPEG, WebP, and AVIF on the same photo?

Accepted Answer

Yes. Change the output format, compress again, and use the slider each time. Keep the tab open for AVIF.

Compress without visible quality loss

How to check quality before you save