How can I reduce video size for mp4 file on my pc?

To reduce video size, the Microsoft Photos approach is your best bet among the built-in options. You don't have to manually set a resolution—just pick a quality preset and let it do its thing.

Windows actually has a built-in video editor that can export compressed videos . It's pre-installed on Windows 10 and available for free on Windows 11.

How to use it to reduce video size:

1. Open Microsoft Photos (look for "Photos Legacy" in the Start menu)

2. Click Video Editor at the top

3. Create a new project and add your video

4. Drag it to the storyboard

5. Click Finish video in the top-right

6. Choose a quality preset

The honest catch: While you don't need to change resolution manually, the quality presets (like "540p for smallest size") are basically lowering the resolution behind the scenes. The method you export with determines the file size—lower quality presets produce smaller files.