How to reduce PowerPoint file size before e-mailing a deck
Most heavy decks are heavy because of a few large photos inserted at full camera resolution, or because of images hidden in unused slide layouts copied over from other decks. Compressing pictures and removing unused layouts usually brings a deck back under typical 20 MB e-mail limits.
Compress pictures (Windows)
- Select any picture, then Picture Format, Compress Pictures.
- Untick Apply only to this picture so the whole deck is compressed.
- Tick Delete cropped areas of pictures, unless you still need them.
- Choose a resolution. 150 ppi is fine for e-mail and screens, 220 ppi for printing.
- Save the file under a new name and compare the sizes.
Compress pictures (Mac)
- Go to File, Compress Pictures.
- Choose a picture quality and apply it to all pictures.
- Save under a new name.
Remove what you cannot see
- Go to View, Slide Master.
- Hover over each layout: PowerPoint shows which slides use it.
- Delete layouts that no slide uses, and masters that came in with pasted slides. Their background images stay in the file even if no slide shows them.
What the manual way misses
- Compress Pictures treats all images the same. A logo shown small and a full-page photo get the same resolution.
- It does not show which images make up most of the file, so you cannot tell whether it was worth it until you save.
- Images in unused layouts and masters are not touched at all.