What quality is lost when you save a jpeg file using MS Paint?

I tried opening an existing jpeg file which has a file size of 4 kb using MS Paint. Then I just save it using MS Paint and the size decreases to 900 kb. I compared the quality of the previous and the new file and I can not distinguish any difference.What quality is lost when you save a jpeg file using MS Paint?
That's what jpeg was design for. It's an advance compression format that has small size while still retaining 99% of the original quality.




How can the size decrease from 4 kb to 900 kb? Sounds like a 225% increase in size to me.



Anyway, Microsoft's JPEG implementation results in a LARGE amount of quality loss. I'd recommended editing files in a more capable editor such as Photoshop or GIMP (which is free), both of which properly use the JPEG format.What quality is lost when you save a jpeg file using MS Paint?
Try saving a colorful, detailed image as a .bmp file in Paint. Then save it again as a .jpg. Close and reopen it, and it looks washed out and grainy.



Maybe going from 4 kb to 900 bytes (I assume your file didn't go UP in bytes) isn'r enough of a jump to notice, but going from, say, 200 kb to 40 kb really shows it.
MS paint version of the jpeg picture is a little bit grainy, and doesn't look smooth as the original version of a picture.What quality is lost when you save a jpeg file using MS Paint?
Use .png instead, no quality is lost at all.