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Considering that Microsoft PowerPoint presentations are generally accompanied with tons of images, gifs, embedded videos, charts, graphs, and other content, it’s no surprise that you get some pretty big files. Here are a few steps you can take to reduce a presentation's file size.

Large files can be annoying. They take up loads of precious disk space, slow down playback performance, and can cause emails to bounce back due to exceeding the file size limit. You can prevent all of these things by reducing the file size of your presentation.

We’ve mentioned it before, but the first thing you’d think of when considering file size reduction is images—and for a good reason. Image files can be quite large. There are steps you can take to reduce the size, such as compressing the images in the presentation. If you suspect the reason your PowerPoint file is so large is due to images, then be sure to read the article we’ve written on how to reduce the size of Office documents that contain images.

Related: How to Reduce the Size of a Microsoft Word Document

We do have some additional tips to add if you followed these steps but still need to reduce your presentation’s file size.

Convert Your Presentation to the PPTX Format

Microsoft released the PPTX format in Office 2007. Still, it’s not uncommon to see PPT files floating around. So what’s the difference between a PPT and PPTX file? The PPTX version compresses all of the content within the presentation. If you have a PPT file and convert it into a PPTX file, you’ll notice a decrease in the file size.

Converting the file is as simple as pressing a button and choosing the file type. Go ahead and open your PPT file, head over to the “File” tab, and then click “Convert.”

Convert presentation

Windows File Explorer will appear. You’ll notice the Save As type is set as "PowerPoint Presentation." This is the PPTX file type. Click “Save.”

Save as type

Your PPT file will now be converted to a PPTX file. As you can see, the size of the file has been reduced.

reduced file example

HTG Presentation 2 is our PPT file, and HTG Presentation 3 is our PPTX file. Merely converting the file type reduced the size by 335 KB.

While this isn’t a breathtaking drop in file size, we managed to reduce a Word document file size from 6,001 KB to 721 KB. It all depends on what’s inside the file. With any luck, this will be the only step you need to take. If not, keep reading.

Insert Your Pictures—Don’t Copy and Paste

It’s tempting to copy and paste an image in PowerPoint instead of using the insert function. This won’t be an issue if you’re not concerned about file size, but if you are, then beware of copy and paste—it may reformat your image to BMP or PNG. Why is this an issue? Both of those file formats are larger than JPG.

png to jpg conversion size difference

You can see in the above screenshot that the PNG file is 153KB compared to the 120KB JPG file of the same image. Each time you copy and paste a JPG file to PowerPoint, and it gets converted to PNG, you’re adding a bit of unnecessary file size to the presentation. Using the insert function will ensure your images are inserted as intended.

Do Image Edits in an Image Editor—Not in PowerPoint

When you insert an image in PowerPoint, it’s best to make sure that it doesn’t need any edits. If it does require edits, you’re better off doing it in an image editor. Why? When you use PowerPoint to edit your image, it stores all of those edits as part of the presentation. For example, when you change an image to black and white, PowerPoint retains the full-color image as well. That’s a lot of extra bites being stored.

If you don’t have an image editor (you do) or you simply must use PowerPoint, be sure to tell PowerPoint to discard all of that excess data saved from the edits. It won't save you as much space as working in a dedicated editor, but it will help.

Compress All of the Images in Your Presentation

You can compress images in PowerPoint one at a time or all at once. If you’re looking to do the latter, here’s how.

Open your presentation, head over to the “File” tab, and then select “Save As” in the left-hand pane.

select save as option

Next, select “More Options,” which you'll find under the area where you would name your file and choose the file type.

More Options in Save as tab

The “Save As” window will appear—this time with a few extra options available to you. Next to the “Save” button, click “Tools.”

Tools in save as dialogue box

In the drop-down menu that appears, select “Compress Pictures.”

Compress pictures option in tools

The “Compress Pictures” window will appear. Here, you can choose the resolution type of the images (based on PPI) in the presentation. You’ll also notice that you’re not able to select the “Apply only to this picture” option in the “Compression Options” group. That’s because, due to the way we accessed this tool, this option isn’t available.

Note: If you do want to compress a single picture, select it and then head to Picture Tools Format > Compress Pictures.

Once you’re happy with your selection, click “OK.”

compress pictures window

Be sure to save your presentation afterward.

Don’t Use Embedded Fonts

We get why you might want to embed fonts—you might be making a Star Wars themed presentation and, as a result, anyone you may be sharing the presentation with is not likely to have those special fonts available to them. Embedding the fonts in your presentation could prevent issues down the line, but it comes at the cost of increased file sizes.

In general, unless you are sure you need to display a particular font, we recommend turning off font embedding.

Head over to the “File” tab and select “Options” at the bottom of the left-hand pane.

Options at bottom of lefthand pane

On the “Save” tab, untick the “Embed fonts in the file” checkbox and then click “OK.”

uncheck embed fonts box

We saved a copy of our presentation with all fonts embedded, without fonts embedded, and with only the fonts used in the presentation embedded. Look at the difference if file sizes:

difference in file size with embedded fonts

Convinced yet?

Consider the difference in file size if you embed an entire YouTube video in your presentation instead of linking back to it. Embedding an entire video will significantly increase the size of your presentation. There are certainly some valuable benefits when embedding a file vs. linking to it (such as when the recipient might not have internet access to play the video), but if the file size is an issue, just don’t do it.

Don’t Store a Thumbnail for the Presentation

Way back when Office let you save thumbnail images of your presentation so that you could get a sneak preview of the file when searching for it in File Explorer. Windows has grown to be more sophisticated, so it no longer requires the help of Office applications to do this. But, the option is still available.

We ran a little test to see the difference in file size with and without this option enabled. Here are the results:

don't save thumbnail

With the thumbnail option enabled, our file size was 2,660 KB. Without the option enabled, the file size was reduced to 2,662 KB, saving a total of 7 KB.

This is a pretty small save, but when we tested it with a Word document, the difference was significant, showing 721 KB without the option enabled, and 3,247 KB with the option enabled.

While this is a large gap between applications and it’s not exactly clear why the difference is so large, it’s still an option worth exploring. To disable the feature, open your presentation, head over to the “File” tab, and then select “Properties” found on the right-hand side, then “Advanced Properties.”

select properties

You’ll now be in the “Summary” tab of the “Properties” window. At the bottom of the window, uncheck the box next to “Save preview picture,” and then click “OK.”

uncheck save preview image

Remove Personal and Hidden Information from Your Presentation

Microsoft Office will store your personal information (such as author name) and hidden properties within your presentation. Getting rid of this information can save you a bit of space.

Open your presentation, head over to the “File” tab, select the “Check for Issues” option, then select “Inspect Document."

Inspect Document

The “Document Inspector” window will appear. Make sure the “Document Properties and Personal Information” box is checked, and then click “Inspect."

Inspect the document

In the next window, select “Remove All.” The information will now be removed, saving you a few KB of space.

Turn Off AutoRecover

We don’t necessarily recommend this, and it should only be used as a last resort effort. AutoRecover is an essential tool in Office, and if you’ve ever lost a document before saving, then you understand precisely what we mean.

Each time Office uses AutoRecover, it adds a little to the size of the file. To turn AutoRecover off, head over to the “File” tab and select “Options” found at the bottom of the left-hand pane.

Options at bottom of lefthand pane

In the “Save” tab of the “Options” window, uncheck the box next to “Save AutoRecover information ever xx minutes.”

uncheck autorecover option

If you save and exit out of the presentation immediately, you won’t notice a difference. Over time though, as you continue to progress through the presentation, the AutoRecover feature will add KB to your file.

Copy Everything Into a New Presentation

While you’re creating your presentation, PowerPoint will save various things in the background to help you out. We’ve mentioned how to turn off a lot of these features, delete data PowerPoint saves, and so on, but there’s always a chance something slipped through the cracks, and PowerPoint stored some information you don’t need. Copying your content over to a new presentation may be a good solution to the problem.

This may be a bit of a hassle though as, with PowerPoint, you’ll need to copy and paste each slide (and master slides). Once you do though, the new presentation won’t have any of the previous background saves, AutoRecover information, or previous versions of the file. As a result, you should see a change in file size.

While we can’t tell you exactly how much this will reduce your file size since each presentation will be different, it’s worth a shot.

A Possibility: Unzip the Presentation and Compress It

As we mentioned earlier, a PPTX file is a compressed file (which is why the size is much smaller than an old-school PPT file). This means you can open it with a tool such as 7-Zip or WinRar, extract all the files from your PPTX, add them to a compressed archive, and then rename the archive to a PPTX file extension.

We had some issues here, though.

In Rob’s testing with his Word document, it successfully reduced the size of the file from 721 KB to 72 KB. However, it corrupted the file in the process. In my testing with my 2,614 KB file, it didn’t corrupt it, but it only reduced it to 2,594KB—a total of only 20 KB. We’re unsure what’s at play here, so if you want to give this a go, be sure to have a backup copy of your file before doing so.


That’s all the tips we've got for reducing the size of your PowerPoint presentation. We’re always looking for new and interesting ways to reduce the size of our files, so if you have any tips, let us know in the comment section, and we’ll be happy to test them out!