How to Make a File Smaller on a Mac

Squash those files down to size

What to Know

  • In Finder: Right-click a file and click Compress to save it as an archive.
  • To resize a PDF, open it in Preview, then click File > Export > Quartz Filter > Reduce File Size.
  • In Pages, reduce a file containing media files by clicking File > Reduce File Size.

This article teaches you numerous methods to make a file smaller on Mac. It looks at how to reduce the size of a file and how to resize a PDF document. It also looks at reducing other file types.

How Do I Compress a Large File on a Mac to Make It Smaller?

If you want to compress a large file on a Mac, the process is quite simple and is the same method for all files. If you're sending the file to someone, it requires the recipient to be able to 'unzip' the file (also known as an archive), but there are plenty of free ways to do this, and some operating systems have the option built-in. Here's what to do. 

  1. In the Finder, find the file or folder you wish to compress.

  2. Right-click the file. 

  3. Click Compress.

    MacOS with Compress highlighted on right-click file menu
  4. Wait for the file to be compressed.

  5. The file is in the same folder with the same name but with the file extension .zip.

How Do I Resize a PDF File on a Mac?

If you have a PDF file that needs resizing and reducing in file size, it takes mere seconds. Here's how to do it using the Preview app.

  1. Open the PDF in Preview.

  2. Click File.

    MacOS Preview app with File highlighted
  3. Click Export.

    MacOS Preview with File menu open and Export highlighted
  4. Click Quartz Filter.

    MacOS Preview app with Quartz Filter on save file dialog highlighted
  5. Click Reduce File Size.

    MacOS Preview app with Reduce File Size highlighted on Save File Dialog
  6. Click Save to save the smaller PDF.

How Do I Reduce the MB Size of a File on a Mac?

Another common file you may wish to reduce the size of is a Pages document. Here's how to reduce the size of a file within Pages. 

This method only works if your Pages document contains images or videos.

  1. In Pages, click File.

  2. Click Reduce File Size.

    Pages on MacOS with File menu open and Reduce File Size highlighted
  3. Choose how you wish to reduce the file size. It's possible to crop and scale images, as well as reduce movie quality to save space.

  4. Click Reduce A Copy to make a second version of the file or Reduce This File to cut down the current verison.

    Pages app on MacOS with Reduce File Size dialog open

How Do I Reduce the Size of a Video File on a Mac?

Video files take up a lot of space. While there are complex ways to reduce a file size, there are also some very simple methods. Here's how to do so using iMovie.

  1. Open iMovie.

  2. Click Create New > Movie.

    iMovie app on MacOS with Create New highlighted
  3. Click File.

    iMovie app with File menu highlighted
  4. Click Import Media to import the file.

  5. Click File > Share > File.

    iMovie app with File Share option highlighted
  6. Adjust the resolution or quality and make it lower.

    It's also possible to strip out the audio or video to further reduce the size.

  7. Click Next.

    iMovie app with File compression options open
  8. Click Save to save the file in a smaller file size.

  • How do I make a picture file smaller on my Mac?

    You can reduce a picture's file size by resizing an image on your Mac. Open a photo in the Preview app > choose Tools > Adjust Size > adjust width and height in the dimensions boxes > OK. You can also select the box beside Resample image and edit the Resolution field.

  • How do I make a PowerPoint file smaller on a Mac?

    Compress images to reduce PowerPoint file size on your Mac. Select File > Compress Pictures > select whether to resize a chosen image or all images > and check the box beside Delete cropped areas of pictures if you want to remove them. Then choose your preferred resolution and click OK.

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