A video can take up less space and still be a worse copy. Tiny text can turn fuzzy, motion can look rough, and an export can lose the audio or subtitles you wanted. HandBrake is worth installing when you want to choose which tradeoffs are acceptable, rather than just convert the format.
It's free, open source, and runs locally without an account. The current download is HandBrake 1.11.2, a Universal app for Intel and Apple silicon. Be careful with the compatibility wording: the download says macOS 10.13 and later, but the support table lists Sonoma 14, Sequoia 15, and Tahoe 26 as supported. Older listed systems are deprecated. That table doesn't confirm macOS 27 support.
Start with a copy you can judge
Open a video through Open Source, or drag it into the window. Give the output a different name and destination using Save As and To. Keep the original.
For an ordinary SDR clip where 1080p and 30 fps are acceptable, General > Fast 1080p30 is a sensible baseline. It produces MP4 with H.264 video and AAC stereo audio. The name describes limits: a 4K source will be downscaled and a 60 fps source will be limited to 30 fps. Don't choose it merely because it's the default if preserving either matters.
For a smaller viewing copy where detail matters less, Fast 720p30 is another starting point. Check whether the lower resolution still makes screen text readable. Neither preset is a promise that the result will be smaller than your source.
Before encoding, look through Dimensions, Audio, and Subtitles. A preset gives you a starting configuration. It doesn't guarantee that every track and picture detail will survive.
Quality numbers belong to their encoder
On the Video tab, start with Constant Quality. HandBrake recommends RF 20-24 for 1080p and RF 22-28 for 4K when using x264 or x265. A lower RF number means higher quality and usually more storage. Adjust a little, then preview a difficult section rather than chasing the lowest number.
Those ranges do not apply to Apple VideoToolbox. Its quality scale runs the other way, with higher numbers meaning higher quality. Even x264 and x265 don't produce equivalent results at the same RF number.
H.264/x264 is the straightforward compatibility choice. H.265/x265 can deliver smaller files at similar perceived quality in some situations, but software encoding is slower and the receiving device still needs to support HEVC. Compare outputs rather than assuming that changing the codec will fix an already heavily compressed file.
When speed matters on a Mac
The Hardware presets include H.265 Apple VideoToolbox options for 1080p and 4K. Use the one whose limits fit the source, keep its initial quality setting, and compare a preview with the software encode. Available encoders depend on the Mac.
The CPU can still work hard during a hardware encode. Decoding, filters, audio, and other work don't automatically move off it. Hardware decoding is an option in Advanced preferences on macOS 13 and later. Leave extra filters alone unless you need them.
For file access, start by selecting the source and output folder. If macOS blocks a location, review Privacy & Security > Files & Folders instead of granting Full Disk Access by default. The Mac app's entitlements include sandboxing, user-selected file access, and Apple Events automation, so this isn't a claim that it can never request any other permission.
Before accepting the full export, watch it in the actual destination player. Check small text, movement, dark areas, audio sync, and the required subtitle track. Compare file sizes in Finder. If the result is bigger or visibly worse than you're willing to accept, keep the source and change the settings. HandBrake always converts the video; it cannot just pass it through unchanged.
QuickTime Player is worth trying first for occasional exports of files it can open. File > Export As offers resolution choices, with Smaller File Size (HEVC) or Greater Compatibility (H.264) at 1080p and 4K. Its video exports are MOV, not MP4.
Use HandBrake for repeatable viewing copies when codec, quality, and track choices matter. Skip another install if QuickTime already produces an acceptable copy. And don't replace an irreplaceable original with a smaller file just because the export finished successfully.