Resize a transparent PNG and keep its clear background. Choose a compatible export format and distinguish real transparency from a white preview area.
Check that the original is transparent
A logo can appear to have a transparent background when it actually contains white pixels. Resizing does not remove that background. Open the source against a contrasting surface or inspect it in an editor to confirm whether the empty area is truly transparent.
If a photo needs its background removed, prepare a cutout with Background Remover first. Keep the resulting transparent image as your source for resizing. This separates the task of identifying the foreground from the task of changing dimensions.
Select a format that retains transparency
Open Image Resizer, select the PNG and enter the required dimensions. Keep the aspect ratio enabled unless intentional distortion is part of your design. Choose PNG as the output format to keep transparent areas in the resized file.
WebP can also carry transparency when your browser supports its export and the destination accepts that format. JPEG cannot preserve those areas in this tool: it fills them with white. Changing a JPEG filename to end in .png does not restore transparency that has already been lost.
Inspect the boundary around the subject
Generate the result and examine thin edges, small lettering and semi-transparent shadows. Reducing a detailed logo to a very small size can make fine strokes disappear. That is a resolution limitation, not necessarily a problem with the transparent background.
The tool uses a checkerboard behind previews to make empty areas easier to see. That checkerboard is a display aid, not a pattern deliberately added to the exported PNG. Some image viewers show transparency as white, so a white display alone is not proof that the export failed.
Save a clear working copy
Download the PNG and place it over a colored background in your intended design. Check that the empty regions reveal the background beneath them. Retain a larger transparent original so future versions can be resized directly from it instead of enlarged from the small copy.