MKV to MP4 Conversion on macOS
Complete macOS guide for converting MKV files to MP4 format. Learn Terminal commands, Homebrew FFmpeg installation, GUI applications, and native macOS tools for seamless video conversion.
What You'll Learn
Install FFmpeg via Homebrew
Terminal commands for conversion
Preserve video quality settings
Batch conversion techniques
GUI application alternatives
Keep subtitles and audio tracks
Optimize for macOS playback
Troubleshooting common issues
Method 1: FFmpeg via Terminal
Professional-grade conversion using command line tools
1Install Homebrew Package Manager
First, we need Homebrew to easily install FFmpeg and its dependencies. Open Terminal and run:
/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"2Install FFmpeg with All Codecs
Once Homebrew is installed, install FFmpeg with comprehensive codec support:
brew install ffmpegVerify installation by checking the version:
ffmpeg -version3Convert MKV to MP4
Navigate to your video folder and use these commands:
🔄 Lossless conversion (fastest, keeps original quality):
ffmpeg -i input.mkv -c copy output.mp4⚡ High quality conversion with H.264:
ffmpeg -i input.mkv -c:v libx264 -crf 18 -c:a aac -b:a 128k output.mp4📝 Preserve all subtitle tracks:
ffmpeg -i input.mkv -c copy -c:s mov_text output.mp44Batch Convert Multiple Files
Convert all MKV files in a folder using a simple bash loop:
for i in *.mkv; do ffmpeg -i "$i" -c copy "${i%.*}.mp4"; doneMethod 2: GUI Applications
User-friendly applications with drag-and-drop interface
1HandBrake (Recommended)
Free, open-source video transcoder with excellent macOS support and presets.
✅ Advantages:
- • Free and open-source
- • Apple Silicon native
- • Excellent quality presets
- • Batch processing
- • Preview functionality
2IINA (Media Player + Conversion)
Modern media player for macOS with built-in conversion capabilities.
✅ Features:
- • Native macOS design
- • Plays MKV natively
- • Simple conversion tools
- • TouchBar support
- • Picture-in-Picture
3Permute 3 (Premium)
Professional media conversion app designed specifically for macOS.
✅ Features:
- • Drag-and-drop interface
- • Background processing
- • Notification Center integration
- • Multiple format presets
- • Watch folder automation
💰 Pricing:
$39.99 on Mac App Store
Free trial available
Advanced Tips for macOS Users
🚀 Hardware Acceleration (Apple Silicon)
M1/M2 Mac users can leverage VideoToolbox for faster encoding:
ffmpeg -i input.mkv -c:v h264_videotoolbox -b:v 5M -c:a aac output.mp4📱 Optimize for Apple Devices
Create files optimized for iPhone, iPad, and Apple TV playback:
ffmpeg -i input.mkv -c:v libx264 -profile:v baseline -level 3.0 -pix_fmt yuv420p -c:a aac -movflags +faststart output.mp4🔧 Automator Workflow
Create a right-click context menu for MKV files:
1. Open Automator → New Document → Quick Action
2. Set "Workflow receives" to "movie files" in "Finder"
3. Add "Run Shell Script" action
4. Paste the FFmpeg command and save
📂 File Associations
Set default applications for MKV files:
1. Right-click any MKV file → "Get Info"
2. In "Open with" section, choose your preferred app
3. Click "Change All..." to apply to all MKV files
4. Recommended: IINA or VLC for playback
Troubleshooting Common Issues
❌ "Permission denied" errors
Solution: Use sudo for Homebrew installation or check file permissions:
sudo chown -R $(whoami) /usr/local/Homebrew❌ "Unknown encoder" errors
Solution: Reinstall FFmpeg with full codec support:
brew uninstall ffmpeg && brew install ffmpeg❌ Slow conversion speeds
Solution: Use hardware acceleration or adjust thread count:
ffmpeg -i input.mkv -threads $(sysctl -n hw.ncpu) -c copy output.mp4❌ "Command not found" errors
Solution: Add Homebrew to your PATH in shell profile:
echo 'export PATH="/opt/homebrew/bin:$PATH"' >> ~/.zshrc && source ~/.zshrcmacOS Performance Tips
⚡ Speed Optimizations
- • Close unnecessary applications during conversion
- • Use SSD for temporary files (set TMPDIR)
- • Enable hardware acceleration on Apple Silicon
- • Use appropriate thread count (# of CPU cores)
- • Convert multiple files simultaneously
🎯 Quality Settings
- • CRF 18-23 for high quality H.264
- • Use -preset slow for better compression
- • Keep original resolution unless necessary
- • AAC 128k sufficient for most content
- • Test with short clips first
Need a Simpler Solution?
While this guide shows professional methods, you can also use our free online MKV to MP4 converter that works directly in your Mac's browser - no installation required!
100% browser-based • No installation needed • Privacy protected • Works on any Mac