Free · No signup · Runs in browser

Free MKV to MP4 Converter

Convert MKV videos to universally compatible MP4 — plays everywhere, no upload needed.

Why use MorphFlux?

MKV to MP4 conversion runs entirely in your browser using FFmpeg WebAssembly — universal compatibility with no server upload.

Universal MP4 compatibility

The output MP4 plays on every device and platform — smart TVs, phones, tablets, and all video players.

Runs locally in your browser

Your MKV files are processed entirely on your device using FFmpeg WebAssembly. Nothing is uploaded to any server.

Preserves audio and subtitles

The audio track is preserved during conversion. Embedded subtitles can be retained in the MP4 container.

Free with no signup required

Convert as many MKV files to MP4 as you need, completely free. No account, no email, no credit card required.

When would you need this?

Common scenarios where converting MKV to MP4 improves video compatibility.

Converting MKV movie files to MP4 for playback on smart TVs, phones, or tablets that don't support MKV

Transforming MKV video files to MP4 for uploading to YouTube, Vimeo, or other video platforms

Converting MKV recordings to MP4 for editing in video software that prefers MP4 containers

About MKV and MP4

Understanding the difference between MKV and MP4 video containers.

MKV

What is MKV?

MKV (Matroska Video) is an open-source video container format that can hold virtually any video and audio codec. MKV is popular for high-quality video files and Blu-ray rips, but is not supported natively by all devices and platforms.

MP4

What is MP4?

MP4 (MPEG-4 Part 14) is the most universally compatible video format, supported by every device, platform, and video player. Converting MKV to MP4 ensures your videos play everywhere.

Frequently Asked Questions

Everything you need to know about converting MKV to MP4 online.

How do I convert MKV to MP4?

Drop your MKV file into the converter above or click to select it. The conversion happens in your browser and you can download the MP4 when ready.

Will the video quality change?

The conversion remuxes the video stream where possible, preserving original quality. In some cases re-encoding is required, which may slightly reduce quality.

Is my file uploaded to a server?

No. All conversion happens locally in your browser using FFmpeg WebAssembly. Your files never leave your device.

How long does conversion take?

Conversion time depends on file size and your device. Most files under 500MB convert in a few minutes in the browser.

Is there a file size limit?

Files up to 200MB are supported. Since conversion happens in your browser, very large files may require significant memory.

Related Tools

More free converters you might find useful.