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Make Smaller guide

Reduce ZIP and 7z Archive Sizes on Windows

Recompress supported archives into separate smaller copies while keeping the files inside unchanged.

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Short answer

Select a ZIP or 7z archive in File Explorer and choose Make Smaller, then Preserve quality. If the archive can be recompressed enough and verified, the app creates a separate copy in the same format. The files inside an ordinary archive remain unchanged, including when you select a stronger profile.

Before you start

  • Make Smaller with an active license on Windows 11 24H2 or later, x64.
  • A supported, unencrypted ZIP or 7z archive available locally, with enough free space for processing.
  • An archive reader for testing the output and a disposable folder if you need to extract samples.

Start here

  1. Choose the archive itself

    Select the .zip or .7z file in File Explorer. This workflow recompresses an existing archive; it does not create a new archive from a selection of loose files.

  2. Start with Preserve quality

    Right-click, choose Make Smaller and select Preserve quality. Balanced and Smallest size do not resize or re-encode the files inside an ordinary ZIP or 7z.

  3. Read the outcome

    Wait for verification. No improvement is common for archives that are already well compressed, particularly those containing compact photos, audio or video.

  4. Test the output

    If a smaller copy exists, choose Show in folder. Open it in your archive reader, compare its file list and use the reader's integrity check if available.

  5. Check sample contents

    Extract representative files into a separate disposable folder and open them. Avoid extracting over your originals. Keep the original archive until the receiving system accepts the inspected copy.

Check your result

  • The output remains ZIP or 7z and opens successfully.
  • Required entries and their contents are present.
  • The actual size is smaller and the original archive is still available.

When an archive cannot be processed

Encrypted archives and certain compression methods or internal features cannot be processed. Read the result instead of changing the filename extension or assuming all ZIP and 7z files are supported.

A file containing a large amount of already compressed material may have no worthwhile saving. The app does not reduce the quality of that material to force a smaller archive.

Office documents have their own rules

Some document formats use ZIP internally, but Make Smaller recognizes them as documents. Eligible embedded images or media can be adjusted by document profiles. Use the PDF and Office guide for those files instead of renaming a document to .zip.

The app used in this guide

Make Smaller

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Related guides

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