JPEG cannot store transparent pixels
A transparent image has pixels that can show the background behind them. JPEG does not have an alpha channel for transparency, so converting a transparent image to JPEG requires filling those areas with a solid color.
If you need the transparent areas to remain see-through, choose PNG or WebP when the receiving app accepts it. If JPEG is required, choose a background color that will work wherever the image is displayed.
Before you convert
- Check whether the destination requires JPEG or accepts PNG or WebP.
- If JPEG is required, choose a background that matches the page, document, or design where the image will appear.
- Preview the converted image against a checkerboard or contrasting surface so you can spot filled transparent areas.
- Keep the transparent original if you may need to use it again on a different background.
Convert with the background in mind
The shrinkpixel converter exposes a background choice when converting to JPEG. That background is used where the source image is transparent; the resulting JPEG will be opaque.
Conversion also re-encodes the image, so inspect the output for quality and color changes before using it. Browser encoder support can vary.