# Resize Video — Resize video resolution on Mac

Scale videos to a standard resolution. Part of OneMacTools, 151 private tools in one native Mac app (macOS 26 or later); category: Video. Runs on your Mac; nothing is uploaded.

Scale videos to 4K, 1440p, 1080p, 720p, 480p or 360p while keeping their shape. Smaller resolutions mean smaller files and smoother playback on older devices.

Page: https://www.onemactools.com/tools/resize-video · Download: https://www.onemactools.com/download · Pricing: https://www.onemactools.com/pricing

## How to use it
1. **Install FFmpeg once.** The first time, OneMacTools offers to install FFmpeg through Homebrew with one click.
2. **Drop your videos.** Add one video or a batch that should all end up the same size.
3. **Choose the resolution.** Pick 4K, 1440p, 1080p, 720p, 480p or 360p in the right-hand panel.
4. **Click Resize.** Each video is scaled so its shorter side matches the resolution, with the other side worked out so nothing is stretched.
5. **Check the copies.** The resized videos, with the resolution in the name, are saved in a new dated folder in Downloads › OneMacTools. Open them with the Preview (eye) button or Show in Finder. Your originals stay the same.

## Options
- **Resolution:** 4K, 1440p, 1080p, 720p (the default), 480p or 360p: 2160, 1440, 1080, 720, 480 or 360 pixels on the shorter side. Landscape and vertical videos both work, and a video already smaller than this is left at its own size.

## Tips
- The resolution applies to the shorter side, so a vertical phone video at 1080p comes out 1080 × 1920, the same quality as a landscape one.
- Videos smaller than the chosen resolution are never enlarged, because that would make the file bigger without adding detail.
- 720p is a good choice for slow connections and older devices, and still looks clear on a laptop screen.
- If you mainly want a smaller file, Compress Video with a Max resolution caps the size without ever enlarging.
- To change the shape rather than the size, use Crop Video or Social Video Presets.

## Questions
**How do I change a video's resolution on a Mac?**
Drop it onto Resize Video, pick a resolution such as 720p and click Resize. The width is worked out from the video's shape, so it's never stretched.

**How do I downscale 4K video to 1080p?**
Choose 1080p and click Resize. The result is much smaller and easier to edit or play on older Macs.

**Will resizing make my video smaller?**
Going down in resolution usually makes the file much smaller. Videos already at or below the chosen resolution are only re-encoded, not enlarged.

**Can I upscale a video to 4K?**
No. Resize Video only scales down, because enlarging can't add detail; videos already smaller than the resolution you pick keep their size.

**What does 720p mean for a vertical video?**
It sets the shorter side, the width, to 720 pixels, so a 9:16 phone clip comes out 720 × 1280.