When converting PNG to JPG makes sense
PNG is lossless, which makes it large for photographs. A 4 MB PNG of a photo often becomes a 400 KB JPG with no visible difference. If you are emailing pictures, attaching them to a job application, or uploading to a site with a size cap, JPG is usually the better pick.
PNG still wins for screenshots with text, logos, diagrams and anything with sharp edges or flat color. JPG adds faint fuzz around such edges, and the file may not even end up smaller.
The transparency issue
PNG can have transparent areas. JPG cannot. When you convert, every transparent pixel is filled with white. For a logo that will sit on a white page that is perfect. For a logo that needs to sit on a colored background, keep it as PNG or WebP.
If you want a different background color than white, the background remover can place your subject on a solid color first, and then you can convert the result.
Choosing a quality value
Start at 85 percent. It keeps photographs clean and typically reduces size by 70 to 90 percent compared with PNG. For screenshots that include small text, go up to 92 or 95 percent to keep letters crisp. Anything under 60 percent will show visible blockiness.
The tool shows the percentage saved for each file, so you can see immediately whether the conversion is worth it. If a screenshot grows or barely shrinks, keep the PNG.
Metadata and batches
PNG files rarely carry location data, but any text chunks and color profiles are not carried forward after re-encoding. You can convert up to 20 files at once, each up to 25 MB, and download them as a ZIP.
A worked example
Say you have a 1920 by 1080 screenshot of a holiday photo saved as PNG at 3.2 MB. Converted to JPG at 85 percent, it might come to around 350 KB, a saving of nearly 90 percent. Open both side by side and the difference is hard to spot.
Now take a PNG of a spreadsheet with thin gridlines and small text. At the same settings the JPG may be 280 KB against a 120 KB PNG, with visible fuzz around the numbers. The rule of thumb is simple: photographs go to JPG, text and line art stay PNG.
If the PNG came from a high resolution display, it may be far larger in pixels than you need. Set a width of 1600 pixels or less in the same step. You get a smaller JPG and one less export to run later.