You can convert Keynote documents to PowerPoint files that can be viewed and edited by PowerPoint users on Windows or Mac OS computers.
Choose Share > Export and then click PPT (PowerPoint).
Click Next.
Type a name and choose a location for the file, and then click Export.
PowerPoint doesn’t support some Keynote features:
Some bulleted text items may be lost. If you hide the bulleted text on a slide (by deselecting Body in the Slide inspector), it is deleted from the outline when you export.
PowerPoint doesn’t support alpha-channel graphics, so if you use a photo cutout frame, the image behind it will appear in front. You may also notice slight variations in other graphics.