MKV a MP4 — sin registro
Convert MKV container files to MP4 without re-encoding the video track. MKV is common for high-definition movies and TV shows but lacks support on most smartphones and streaming devices.
Drop your MKV file here
or click to select file
Supports MKV files - Free 100MB (Pro: 500MB)
Selected Video
Conversion Options
Converting...
This may take a few minutes depending on file size
Uploading...
Conversion Complete!
Your MP4 file is ready to download
Need AI video analysis or transcription? Explore Pro video tools →
Why Convert MKV to MP4?
MKV is powerful but not universally supported. MP4 works everywhere.
Universal Compatibility
MP4 plays on all devices - smartphones, tablets, smart TVs, and gaming consoles without any extra software.
Easy Sharing
Upload to YouTube, social media, or send via messaging apps. MP4 is accepted everywhere.
Quality Preserved
Our converter maintains the original video quality. No degradation in your footage.
How to Convert MKV to MP4
Upload MKV File
Drag and drop your MKV file or click to browse your computer.
Choose Settings
Select quality and resolution options. Keep original quality or compress for smaller files.
Download MP4
Wait for conversion to complete and download your MP4 file.
MKV vs MP4 Comparison
video_fileMKV Format
- +Multiple audio/subtitle tracks
- +Chapter support
- +High quality container
- -Limited device support
- -Not accepted by most platforms
video_fileMP4 Format
- +Universal compatibility
- +Widely accepted online
- +Efficient compression
- +Plays on all devices
- -Fewer advanced features
Convert Large MKV Files Without Watermarks
FastlyConvert is built for the most common MKV sharing problem: you have a high-quality video that plays in VLC, but not on your phone, TV, browser, or upload form. Keep the original quality setting when you only need MP4 compatibility, or choose a smaller resolution when the MP4 must be easier to send.
Free up to 100MB
Convert smaller MKV clips with no sign-up, no watermark, and no software install.
Pro up to 500MB
Use Pro for longer MKV videos, priority processing, and larger upload support.
Need smaller output?
After converting to MP4, use the video compressor to target email, Discord, or WhatsApp sizes.
Frequently Asked Questions
Is FastlyConvert MKV to MP4 really free? expand_more
Yes. FastlyConvert lets you convert MKV to MP4 free online with no sign-up and no watermark. The free tier supports MKV files up to 100MB. Pro supports files up to 500MB with priority processing, and no software install is required.
How do I convert MKV to MP4 online for free? expand_more
Open this page, drag your MKV file into the upload area or click to select it, then click Convert to MP4. When the conversion finishes, click Download MP4. The full process usually takes a few seconds because FastlyConvert remuxes streams instead of re-encoding when possible.
Does converting MKV to MP4 reduce quality? expand_more
No. When the source codecs (typically H.264 or H.265 video and AAC or AC3 audio) are MP4-compatible, FastlyConvert remuxes the streams into the MP4 container without re-encoding. The output MP4 keeps the exact same video and audio quality as your original MKV. Quality loss only occurs if you intentionally choose lower resolution or higher compression.
How fast is the MKV to MP4 conversion? expand_more
Most MKV to MP4 conversions complete in seconds because FastlyConvert remuxes the container rather than re-encoding the streams. A typical 1GB MKV file converts in 10 to 30 seconds depending on your connection speed. Re-encoding (when codecs are not MP4-compatible) takes longer, usually 1 to 3 minutes per gigabyte.
Can I convert MKV to MP4 in high quality? expand_more
Yes. Free users can convert MKV files up to 100MB while preserving original quality. The remux process keeps the exact same video bitrate and resolution as your input file when possible. Pro users can convert files up to 500MB and access faster processing queues.
Will subtitles be preserved when I turn MKV into MP4? expand_more
Yes. FastlyConvert preserves subtitle tracks when converting MKV to MP4. Soft subtitles in MKV (typically SRT or ASS) are converted to the MP4-compatible mov_text format so they remain selectable in players like VLC, IINA, and most smart TVs.
Why won't my MKV file play on my TV or phone? expand_more
Many TVs, smartphones, and built-in players do not support the MKV container format or some of the codecs commonly used inside MKV files. Converting MKV to MP4 makes the file compatible with iPhone, Android, smart TVs, Quick Look, web browsers, and almost every other player.
What is the difference between MKV and MP4? expand_more
MKV (Matroska) is a flexible container that can hold multiple video, audio, and subtitle tracks, including formats that other containers do not support. MP4 (MPEG-4 Part 14) is more standardized with universal device compatibility but supports fewer track types. For archiving and complex media, choose MKV. For sharing, uploading, and everyday playback, choose MP4.
Is FastlyConvert safe? Does it upload my video to a server? expand_more
Files are uploaded over HTTPS to our processing server, the conversion runs there, and the converted MP4 is auto-deleted within 24 hours. We never sell or share file content. See our Privacy Policy for full data-handling details.
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MKV to MP4 Converter - Convert MKV Video Files Online Free
Need to convert MKV to MP4? Our free MP4 converter transforms your MKV video files into universally compatible MP4 format while preserving high quality video and audio. Simply drag and drop your MKV file or use dragging and dropping from your file manager - the conversion starts instantly and converts your video in seconds.
Why Convert MKV to MP4 Format?
MKV file format is great for storing MKV video with multiple audio and subtitle tracks, but MP4 format offers better compatibility with every media player, smartphone, and streaming platform. Our MP4 converter preserves the original file size and quality while changing the video format.
Preserves Audio and Subtitle Tracks
Unlike other converters, we keep your audio and subtitle tracks intact. Your MP4 video will maintain all the subtitle tracks from the original MKV file. Perfect for movies with multiple languages or hearing-impaired captions.
Features of Our MKV to MP4 Converter
- • High Quality Output: Maintains original high quality - no re-encoding means no quality loss
- • Fast Conversion: Drag and drop your MKV and get your MP4 file in seconds
- • Universal Playback: MP4 video plays on any media player - VLC, Windows Media, QuickTime
- • Optimal File Size: Smart compression keeps file size small without sacrificing quality
- • Multiple Tracks: Preserves video and audio streams including all subtitle tracks
How to Convert MKV Video Files
Converting video files is easy: drag and drop your MKV file into the upload area, or click to browse. Our converter automatically detects the video format and starts processing. Within moments, your MP4 file will be ready to download. The converted MP4 video is compatible with all video files players and mobile devices.