Convert MP4 to MKV
Convert MP4 video files to MKV format
MP4 file
Result
Your result appears here.
Choose a file to begin.
Good to know
- Every video and audio track is copied into the MKV unchanged, so there is no quality loss.
- Subtitle tracks are not carried over.
- The file keeps your file name with the .mkv extension.
Free Online MP4 to MKV Converter
Our MP4 to MKV converter transforms your MP4 video files into the versatile Matroska (MKV) container format. MKV is an open-standard multimedia format that supports multiple audio tracks, subtitle streams, chapter markers, and metadata within a single file, making it ideal for media libraries and home theater setups.
The online video format converter offers two ways to convert: on your device, where your file is not uploaded, or by uploading files up to 95 MB to Toolsvana. On your device, every video and audio track is copied unchanged, so there is no quality loss; subtitle tracks are left out.
If you want several audio languages in one file for a media server, the exact video quality kept, or access to the MKV container format's advanced features, our converter handles the job without requiring software downloads. Video and audio tracks are copied as they are, so nothing is re-encoded.
Key Features
- High-quality MP4 to MKV conversion with preserved video and audio fidelity
- Conversion on your device, with no upload
- Optional upload to Toolsvana for files up to 95 MB
- All tracks copied without re-encoding, so there is no quality loss
- MKV container support for multiple audio tracks and subtitle streams
- Original resolution, frame rate, and metadata preservation
- Real-time progress tracking with processing statistics
- Video preview and information display before conversion
- Every video and audio track copied in one pass
- Support for MP4 files up to 500MB
How to Use the MP4 to MKV Converter
- Upload your MP4 file: Click "Choose MP4 File" to select a video file from your device (up to 500MB supported).
- Review video details: Examine the displayed video information including format, duration, resolution, and file size.
- Choose settings: Choose whether to convert on your device or upload the file to Toolsvana (up to 95 MB). There are no quality or codec settings, since every track is copied.
- Convert to MKV: Click "Convert to MKV" and watch the progress bar as the conversion runs. Processing stats are shown upon completion.
- Download the MKV file: Review the conversion summary comparing input and output details, then click "Download MKV" to save the file.
Use Cases
- Home theater libraries: Convert MP4 files to MKV to take advantage of multiple audio tracks and embedded subtitle support for media server playback.
- Multi-language content: Keep every audio language track of your MP4 together in a single MKV file.
- Subtitles: Subtitle tracks are not carried over; add subtitle files to the MKV afterwards with a desktop tool such as MKVToolNix.
- Media archiving: Use MKV's open-standard format for long-term video archiving; tracks are copied without re-encoding, so nothing is lost.
- Video editing workflows: Convert to MKV for editors that prefer the format's flexible stream handling and chapter marker support.
- Streaming media servers: Prepare content for Plex, Jellyfin, and Kodi which offer excellent MKV playback and metadata handling.
- Quick container change: Move a video into MKV without re-encoding, so it keeps its exact quality and converts quickly.
Frequently Asked Questions
Why convert MP4 to MKV?
MKV offers superior container features including support for unlimited audio tracks, subtitle streams, chapter markers, and metadata. It is an open-standard format widely supported by media players like VLC, Kodi, and Plex.
Can I change the codec?
No. The converter copies every video and audio track as it is, so each keeps its codec and quality.
Will the conversion affect video quality?
No. Every video and audio track is copied without re-encoding, so they keep their exact quality.
Tips & Best Practices
- Convert on your device: Converting on your device keeps your file private, since it is not uploaded to any server.
- Check the source codec: The MKV keeps the codecs of your MP4, so a player that cannot play the MP4's video will not play the MKV either.
- Expect a similar file size: Since nothing is re-encoded, the MKV is about the same size as the MP4 and keeps every detail of your original video.
- Check player compatibility: Ensure your target media player supports MKV format. VLC, Kodi, Plex, and most modern players handle MKV natively.
- Compare file sizes: After conversion, review the before/after file sizes shown in the summary to verify the result meets your storage requirements.
- Try the upload option: If conversion on your device fails on certain MP4 files, files up to 95 MB can be converted with Upload to Toolsvana.