Why did my watermarked image come out as a heavy PNG, and how do I get a JPG instead?
Because the tool never changes the format: a PNG in is a PNG out, and PNG stores every pixel losslessly, which makes it heavy for photographs. The tool has no output format option, so the fix is to convert the watermarked image to JPEG afterwards with the format converter, picking a background color if it has transparent areas.
Where did the PNG come from?
- Screenshots on most phones and computers are saved as PNG. A product image you took as a screenshot of a supplier's catalogue is most likely a PNG.
- Some design and editing apps export PNG by default.
- Cut-out product shots on a transparent background are PNG because JPEG cannot store transparency.
In all these cases the watermark tool keeps the format, so bag.png comes out as bag-watermarked.png, still a PNG. That is deliberate: silently switching formats could destroy the transparency you need.
Convert after watermarking, not before
There are two possible orders, and the difference is how many lossy saves you get:
- Watermark first, then convert: the PNG is saved after watermarking with no loss, then turned into JPEG once at the quality you choose. Just one lossy save.
- Convert first, then watermark: the image becomes a JPEG at your chosen quality, then the watermark tool saves it again at quality 92. Two lossy saves, and the final size is set by 92, not by you.
The first order is cleaner and leaves the final size in your hands. The second is acceptable if converting first is more convenient, but it will not give you the smallest file.
Steps
- Watermark your PNG images in the Image watermark editor tool and download them.
- Open the Image format converter, choose the watermarked images and pick JPEG as the output.
- If they have transparency, choose the background color that will fill it, such as white for white product pages.
- Pick the quality, compare the sizes and download.
When to keep PNG or choose WebP
- If the image is a cut-out product you will place over a design or a colored background, converting to JPEG bakes the background in for good. Keep it as PNG, or convert to WebP, which keeps transparency at a smaller size, once you have checked your platform accepts it.
- Images with lots of text and hard edges, such as a screenshot of a size chart, stay cleaner as PNG. JPEG can add smudges around letters.
- Ordinary product photographs are where JPEG gains the most.
Common questions
Can I make the watermark tool save JPEG directly?
No, the output always matches the input format. Converting is a separate step.
Does the watermark disappear when converting?
No. The mark is now part of the pixels, so it goes with the image into any format.
Should I convert WebP images too?
WebP is saved at quality 92 and is usually small. Convert it only if your platform does not accept it.