How to Shrink Images in PowerPoint and Word
A deck or document full of phone photos gets huge fast. Here is how Office's Compress Pictures works on Windows and Mac, and when to shrink the photos before they go in.
To compress an image in PowerPoint or Word, select the picture, open the Picture Format tab, click Compress Pictures, pick a lower resolution, and click OK. That is Microsoft's own method, and it works in the desktop apps for Windows and Mac. If you'd rather shrink a photo before it goes into the file, Compress Image does it in your browser, with nothing uploaded.
How to compress pictures in PowerPoint and Word on Windows
These steps come from Microsoft's page Reduce the file size of a picture in Microsoft Office, which covers Word, PowerPoint, Excel and Outlook:
- Select a picture. If the Picture Format tab doesn't appear, double-click the picture.
- On the Picture Format tab, in the Adjust group, click Compress Pictures.
- Leave "Apply only to this picture" ticked to compress just this one, or untick it to compress every picture in the file.
- Under Resolution, choose a lower option and click OK.
The same dialog has a "Delete cropped areas of pictures" box. When you crop a picture in Office, the hidden part stays in the file; ticking this box throws it away and makes the file smaller. Microsoft's Reduce the file size of your Word documents warns that deleted cropped data can't be restored, so do it on a copy if you might re-crop later.
How to compress pictures on a Mac
Microsoft's page gives two routes on a Mac. To compress everything, open the File menu and choose Compress Pictures. To compress only some, hold Shift, select those pictures, and click Compress Pictures on the Picture Format tab. Then pick an option in the Picture Quality box and tick "Delete cropped areas of pictures" if you want the extra saving. If you came in through the Picture Format tab, also choose "Selected pictures only" or "All pictures in this file"; Microsoft notes those two options are unavailable when you start from the File menu.
Compress Pictures isn't available in Microsoft 365 for the web, according to the same page. In the browser version, shrink the photo before you insert it.
Stop big photos coming back
Compress Pictures fixes the pictures already in the file. To keep new ones small on Windows, go to File > Options > Advanced and look under Image Size and Quality. Microsoft's Word guide suggests:
- Set Default resolution to 150ppi or lower. Microsoft says most documents don't need more.
- Make sure "Do not compress images in file" is unticked.
- Tick "Discard editing data" if you don't need to undo picture edits. After that, an edited picture can't be restored to its original.
How to shrink photos before you insert them
Office's dialog offers resolution choices, not a file size. When you want to know how big each photo will be, compress it first:
- Open Compress Image and drop in your photos. It takes JPG, PNG and WebP, up to 50 at once. An iPhone HEIC needs converting to JPG first.
- Move the quality slider (it starts at 0.8) and watch the "Estimated output" line, or type a limit into "Target max size in MB".
- Download and insert the result. Several photos come back in one zip.
The photo keeps its format and file name, and its width and height stay the same unless a target is too tight to reach at full size, in which case the tool scales it down until it fits. If compressing would make a file bigger, you get the original back. A photo straight off a phone is often far wider than a slide needs; Resize Image starts at 1920 pixels wide and keeps the proportions, which also cuts the file size.
FAQ
Why is my PowerPoint so big?
Usually the pictures. Phone photos go in at full resolution, and cropped parts stay in the file until you delete them with Compress Pictures. For more on what drives size, see why an image file is so big.
Does Compress Pictures lower quality?
It lowers resolution, and Microsoft notes the picture can look different afterwards, so check it at the size you'll present.
How small does the file need to be to email it?
See how to compress a photo for email for attachment limits.