How to Compress MP4 Files on MacSave 50-70% storage space without losing quality
What Is MP4 (MPEG-4 Part 14)?
MP4 is the most widely used video container format. It stores video, audio, subtitles, and metadata in a single file. Developed by the Moving Picture Experts Group, MP4 is the standard format for streaming, sharing, and storing video content across virtually every platform and device.
Why Are MP4 Files So Large?
MP4 files are large because modern cameras record at high resolutions (4K at 3840x2160 pixels) with high bitrates. A single minute of 4K video at 60fps can use 300-400MB. iPhone ProRes recordings push this even higher. The H.264 codec commonly used in older MP4 files is also less efficient than newer codecs like H.265/HEVC.
Typical MP4 Compression Results
Before
100MB - 2GB per minute (4K)
After
30MB - 600MB per minute
50-70%
Smaller
Compression Ratio
2:1 to 3:1
Codecs
H.264 (AVC), H.265 (HEVC), AV1
How to Compress MP4 Files on Mac (Step by Step)
Follow these steps to compress your MP4 files using MediaOptim on macOS:
Open MediaOptim
Launch MediaOptim on your Mac. It works natively on both Intel and Apple Silicon.
Add your MP4 files
Drag and drop your MP4 files or folders into the app. MediaOptim can process hundreds of files at once.
Choose compression level
Select your preferred quality. "Balanced" gives the best size-to-quality ratio for most MP4 files, saving 50-60%.
Start compression
Click compress. MediaOptim uses hardware-accelerated HEVC encoding on Apple Silicon Macs for fast processing.
Review and save
Preview the compressed video side-by-side with the original. Save when you are satisfied with the quality.
MP4 Technical Details & Compression Tips
Best Quality Settings
Use H.265 (HEVC) codec with CRF 23-28. For most users, CRF 25 delivers visually identical quality at 50-60% smaller file size. Keep the original resolution unless you specifically need a smaller frame size.
When to Convert vs Compress
MP4 is already the most compatible format. Instead of converting, focus on re-encoding with a more efficient codec (H.264 to H.265). Only convert to WebM if you need files specifically for web embedding.
Technical Specifications
- Container format supporting H.264, H.265, AV1, and AAC audio
- H.265/HEVC provides 40-50% better compression than H.264 at same quality
- Variable bitrate (VBR) encoding saves space on static scenes
- Two-pass encoding improves quality consistency across the file
- Hardware acceleration available on Apple Silicon for fast HEVC encoding
Frequently Asked Questions
How much can I compress an MP4 file on Mac?
Typically 50-70% without visible quality loss. A 1GB MP4 file can be reduced to 300-500MB by re-encoding with H.265/HEVC codec using MediaOptim.
Will compressing MP4 reduce video quality?
With proper settings, compressed MP4 files are visually identical to the originals. MediaOptim uses perceptual quality metrics to ensure the compression is transparent to human eyes.
Can I compress MP4 files without converting to another format?
Yes. MediaOptim compresses MP4 files and outputs MP4 files. The container stays the same while the video is re-encoded with a more efficient codec.
How long does it take to compress a 1GB MP4 on Mac?
On an Apple Silicon Mac (M1 or later), approximately 2-5 minutes for a 1GB file using hardware-accelerated HEVC encoding. Intel Macs take 5-15 minutes.
Is it better to compress or convert MP4 files?
For most uses, compressing (re-encoding) the MP4 is best. The MP4 container is already the most compatible format. Converting to another format only makes sense for specific needs like WebM for web use.
Compress Your MP4 Files Now
Save 50-70% on your MP4 files. No quality loss. Everything stays on your Mac.
Try MediaOptim Free10 files free. No credit card. No signup.