PDF download Download Article
A complete guide to reducing file and video size with 7-Zip
PDF download Download Article

This wikiHow teaches you how to make a .7z or .zip file as small as possible on your PC or Mac. Although the built-in compression tools on both Windows and macOS can compress files quite well, neither gives you the option to add a higher level of compression. Thankfully, there's a free, easy-to-use Windows app called 7-Zip that gives you more control over your file's final size. Although there's no 7-Zip app for macOS, you can use a similar app called Keka to compress files in the 7Z format and achieve comparable results. Keep in mind that files that are already in compressed formats, such as MP3, AVI, MPG, and JPG files, won't get much smaller than their actual sizes when compressed into ZIP or 7Z files.

Compressing Files with 7-Zip

  1. Install 7-Zip for Windows.
  2. Right-click the file you want to compress.
  3. Select 7-Zip > Add to archive…
  4. Select 7z as the archive format.
  5. Select Ultra as the compression level for the smallest file.
  6. Select LZMA2 from the compression method menu.
  7. Click OK .
Section 1 of 3:

Using 7-Zip for Windows

PDF download Download Article
  1. 7-Zip is a free file compression utility that provides more compression options than the standard Windows zip/unzip tool. You can download it for free from www.7-zip.org .
    • Once downloaded, double-click the installer and follow the on-screen instructions to install 7-Zip.
  2. If you want to compress multiple files into one ZIP, you can add them to a folder and right-click that, or just hold down the Control key as you click each file, and then right-click the highlighted area.
    Advertisement
  3. A few options will appear.
    • If you're using Windows 10 or earlier, you will see this option. If you're using Windows 11, click Show more options at the bottom of the right-click menu, then select 7-Zip .
  4. 7-Zip will open to the Add to Archive screen.
  5. The ZIP format is the easiest to open on other platforms, but if you choose the 7z format, you can use a higher level of compression, which will result in a smaller file.
    • If you plan to send a 7z file to someone else or share it over BitTorrent, they'll be able to decompress it without installing additional software on a Mac. If they are using Windows, they'll need to install 7-Zip or another 7z-compatible archive program.
  6. This will produce the smallest possible file size. However, Ultra compression will greatly increase the amount of time your computer will spend compressing the file, so if you want to move quickly, opt for a lower compression level. [1]
  7. LZMA2 is the latest update to LZMA. Either of these options will provide a faster compression level than the others. [2]
  8. 8
    Select a dictionary size (optional). 7-Zip will choose a default dictionary size based on the compression level you selected. If your file is very large, you can increase the dictionary size beyond the 16 MB default to reduce the size of the file, but it will take much longer to compress. The maximum dictionary size is 3840 MB. [3]
  9. When 7-Zip finishes creating your compressed file, it will appear in the same folder as the original files—it's the file with a .zip or .7z file extension.
    • To see the file size of the compressed ZIP, right-click the .7z or .zip file and select Properties .
  10. Advertisement
Section 2 of 3:

Using Keka for Mac

PDF download Download Article
  1. Keka is a free, open-source file compression tool for macOS that provides more compression options than the built-in zip archive utility. To download Keka, open the App Store on your Mac (the blue icon with a white "A" inside) and search for keka . When you find it, click the GET button to install the app. [4]
  2. Once Keka is installed, you'll find it in your Launchpad and the Applications folder.
  3. For the best level of compression, go for 7z or GZIP . ZIP is the most common and can be opened on any platform without installing additional tools, but based on benchmark tests, 7z will actually compress the ZIP to a much smaller size than other formats, and at a faster speed. It's especially better at highly compressing video files. [5]
    • You won't need to install special software on your Mac to decompress a 7z file, but Windows users would need to install 7-Zip (free).
  4. When the slider is at the "Slow" position, Keka will compress the file to the smallest size possible. [6] Because the compression will be so high, the process will take a lot of time, hence the word "Slow."
    • Leave the remaining options set to their defaults for the best level of compression at the fastest possible time.
  5. If you want to compress multiple files into one 7z file, you can add them to a folder and drag the folder to the app. Alternatively, hold down the Command key as you click each file, and then drag the highlighted files to Keka. This will compress the files into a 7z, ZIP, or whichever you selected.
    • To see the size of the resulting file, click it once in Finder, and then press Command + I to view its file info.
  6. Advertisement
Section 3 of 3:

FAQ

PDF download Download Article
  1. 1
    What does compressing a file do? Compressing a file, such as a video, photo, audio file, or program, makes the file smaller so it takes up less space on your device. Compressing files can make backing up data faster and make it far easier to share large files with others. https://www.lenovo.com/us/en/glossary/compressed-file
  2. 2
    How do I reduce the MB size of a file? If you're trying to reduce the size of a video file, you can save the video in a compressed format like MP4 using a codec like H.265 or H.264. You can compress any file using free software like 7-Zip, which is a fast way to get a super-small file on Windows and Mac. [7]
    • There are many software options for compressing video, including FFmpeg and HandBrake .
  3. 3
    What can you do when a ZIP file is still too big? You can split the ZIP file into multiple parts using 7-Zip or WinRAR, or use 7-Zip to compress the ZIP file into an even smaller archive.
  4. 4
    Is 7z better than ZIP? To make the smallest file possible, use 7-Zip, as it allows you more control over your compression options than WinZIP. However, not everyone has 7-Zip (or a program that can decompress 7z files) installed on their computers, so it might be beneficial to use ZIP files if you're worried about compatibility.
  5. Advertisement

Expert Q&A

Ask a Question
      Advertisement

      Video

      Tips

      • If you need to compress a ZIP or 7-Zip file that contains an already-compressed format, begin by reducing the sizes of the files you're compressing. This could mean cutting off the excess from an audio file or reducing the resolution of a JPG .
      • Both 7-Zip and Keka allow you to split a ZIP or 7z file into smaller files as well as create one larger file.
      Submit a Tip
      All tip submissions are carefully reviewed before being published
      Name
      Please provide your name and last initial
      Thanks for submitting a tip for review!
      Advertisement

      About This Article

      Article Summary X

      1. Install 7-Zip.
      2. Right-click the file(s) you want to zip.
      3. Select 7-Zip and click Add to archive…
      4. Select ZIP or 7z as the archive format.
      5. Choose LZMA2 or LZMA as the compression method.
      6. Click OK .

      Did this summary help you?
      Thanks to all authors for creating a page that has been read 228,106 times.

      Is this article up to date?

      Advertisement