Published on May 13, 2025 5 min read

How to Convert MKV to MP4 for Free: Online and Offline Methods

Some video formats look ideal on paper but often end up causing unnecessary complications. MKV is one of them. It's flexible, supports multiple video, audio, and subtitle tracks, and is widely used for storing high-quality media. But when it comes to compatibility, especially with older players or devices, MKV files tend to be more of a hassle than a help. That’s where MP4 comes in. It’s lighter, smoother to handle, and works across pretty much everything—from smartphones to TVs and video editing apps.

If you've ever downloaded a video and found it wouldn't play on your machine, the chances are it was in the MKV format. Solution? Convert it to MP4. It's quicker than you might think, and the quality is practically identical—if you use the appropriate converter.

Online Converters: Quick and No Installation Required

If you're just converting a handful of files and don't feel like downloading software, an online converter is the best option. They're web-based, so you can access them from anywhere with a browser and an internet connection.

CloudConvert

CloudConvert is a veteran service, and there's a good reason for that. It's straightforward, minimalist, and does its job without making too much of a demand. You add your MKV file, choose MP4 as output, adjust settings if necessary, and press convert. It does batch conversion, as well. The free service has daily limitations, but they're sensible unless you're trying to convert whole seasons of video material all at once.

Convertio

Convertio works almost the same way. You can drag your MKV file from your computer, Dropbox, Google Drive, or even a URL. Once uploaded, you choose MP4, make any adjustments, and then download the result. The interface is minimal, and there’s no real learning curve. While free users have size limits, Convertio’s speed is decent for most everyday tasks.

FreeConvert

FreeConvert lives up to its name. It supports video files up to 1GB without asking you to sign in. It also lets you tweak frame rate, resolution, and codec settings, which is useful if you're converting files for a particular purpose, like uploading to a specific platform or saving space on your phone.

Online-Convert

Online-Convert offers more than just basic conversion. It lets you choose presets based on the device you're using—like Android, iPad, or PS5. You can also change the bitrate and screen size and add filters. It's ideal if you want more control without installing anything. Files can be uploaded from your computer, cloud services, or a link.

Zamzar

Zamzar is another long-standing online tool. It’s very easy to use—just upload, select MP4 as output, and convert. It sends you an email when your file is ready to download, which is helpful if you’re multitasking. The free version supports files up to 50MB, which is fine for short videos or clips.

Offline Tools: Reliable and Better for Bulk Jobs

Online converters are fine in a pinch, but they’re not great for heavy lifting. If you have large files, slow internet, or a long queue of videos to convert, desktop software makes more sense. Once installed, these tools don’t rely on your internet connection and tend to offer more control.

HandBrake

HandBrake is often the first name that comes up when discussing video conversion—and rightly so. It’s open-source, free, and works across Windows, Mac, and Linux. You load up your MKV file, pick a preset (like “Fast 1080p” or “iPhone”), set the output format to MP4, and press start.

It may look technical at first glance, but once you try it a few times, it becomes second nature. It’s great for batch conversion, and it handles large files without a hitch. There's even an option to queue up several videos and let your computer do the work while you’re away.

VLC Media Player

Most people know VLC as a media player, but it also has a built-in conversion feature that many don’t use. You go to Media > Convert/Save, add your MKV file, and choose MP4 as the output format. It’s not as advanced as HandBrake in terms of presets, but it works perfectly well for straightforward conversions.

It’s especially handy if you already have VLC installed and just want to convert the occasional file without installing anything new.

Any Video Converter (AVC)

The free version of Any Video Converter supports a wide range of formats and includes options for trimming, cropping, and adding subtitles. The interface is user-friendly, and it lets you drag and drop files into the window for quick access. The software does suggest installing extra tools during setup, so keep an eye out for that and skip anything unnecessary.

Shotcut

Shotcut is a free, open-source video editor, but it’s also excellent for converting MKV to MP4. Just open your file, set the export format to MP4, and hit export. It supports hardware encoding and a wide range of codecs. While it's mainly a video editor, it works well for simple format changes and gives you full control over the output quality.

Format Factory

Format Factory is a Windows-only tool that handles all kinds of media conversions, not just video. It supports batch processing and allows you to fine-tune settings like resolution, quality, and subtitles. The interface looks a bit dated, but it's functional. It also includes options to repair damaged video files, which is a bonus.

Final Thoughts

MKV is great for storage, but not for playback on every device. MP4 simplifies that. With the tools shared here, you can convert your MKV files without spending a cent or dealing with complicated software. Whether you want something quick online or a reliable offline solution, the choice depends on your needs. Either way, the process is straightforward. Just pick the tool that fits your setup, tweak your settings if needed, and let it run. You’ll be watching your videos without format issues in no time.