How to Reduce the File Size of a PowerPoint (Compress Pictures and Media)
"The file is too large to send" usually means one thing: photos straight off a phone, each one several megabytes, when the slide only needs a fraction of that. PowerPoint can shrink them all in one go, and it can do the same for videos.
Quick reference
| What you want | How |
|---|---|
| Shrink every picture | Select any picture → Picture Format → Compress Pictures → untick Apply only to this picture |
| Throw away cropped-off parts | Tick Delete cropped areas of pictures |
| Shrink videos and audio | File → Info → Compress Media |
| Always compress on save | File → Options → Advanced → Image Size and Quality |
| Remove leftover masters | View → Slide Master → delete unused ones |
1. Compress all the pictures
1. Click any picture on any slide.
2. Go to Picture Format → Compress Pictures.
3. Untick Apply only to this picture so it does every picture in the file.
4. Tick Delete cropped areas of pictures.
5. Choose a resolution: HD (330 ppi) for printing, Web (150 ppi) for most presentations, E-mail (96 ppi) for the smallest file.
6. Click OK and save.
2. Go to Picture Format → Compress Pictures.
3. Untick Apply only to this picture so it does every picture in the file.
4. Tick Delete cropped areas of pictures.
5. Choose a resolution: HD (330 ppi) for printing, Web (150 ppi) for most presentations, E-mail (96 ppi) for the smallest file.
6. Click OK and save.
Check a couple of photos afterwards. If one looks soft, undo and choose a higher resolution.
2. Compress videos and audio
File → Info → Compress Media and choose Full HD (1080p), HD (720p) or Standard (480p). This also discards trimmed-off parts of videos. It can take a few minutes for long clips. Save when it's done — and keep the original videos somewhere in case you need them.
3. Make it the default
File → Options → Advanced, under Image Size and Quality, set Default resolution to 150 ppi and make sure Do not compress images in file is unticked. New pictures are compressed automatically when you save.
4. Remove hidden bulk
• Unused slide masters — pasting from other decks brings their masters along. View → Slide Master, right-click each unused one → Delete Master.
• Embedded fonts — File → Options → Save, untick Embed fonts unless you need it.
• Old versions — File → Info → Check for Issues → Inspect Document removes hidden data and comments.
• Embedded fonts — File → Options → Save, untick Embed fonts unless you need it.
• Old versions — File → Info → Check for Issues → Inspect Document removes hidden data and comments.
5. Find what's big
Save the file, then rename a copy from .pptx to .zip and open it. The ppt/media folder shows every picture and video with its size. The biggest culprits jump out.
6. When it's still too big
Save as PDF with Minimum size, share it from OneDrive and send a link, or export as a video. Email attachments over 20 MB will bounce from many systems whatever you do.
Troubleshooting
Compress Pictures didn't change anything. The pictures are already small, or Do not compress images in file is ticked in Options.
My pictures look blurry now. You chose 96 ppi. Undo, and use 150 ppi or higher.
The file is big but has no pictures. Check for an embedded video, an embedded Excel workbook behind a chart, or dozens of unused masters.
Wrapping up
Compress Pictures with Apply only to this picture unticked, Compress Media for videos, delete spare masters. A 60 MB deck becomes a 6 MB one, and it emails first time.
