How to Convert MKV to MP4: A Guide

Anyone who handles different video formats knows how much of a hassle it can be. Various apps support different file types, and not all of them play well with every software. A common problem, for example, is converting MKV files to MP4.

Both MKV and MP4 files can store HD video, but MKV files bundle subtitles, audio, and video together, which makes them large and less compatible with many players. MP4 files, however, are smaller, work with more devices, and don’t sacrifice quality. Because finding a player that supports MKV is tough, many people convert them to MP4 for easier viewing.

MKV vs. MP4

MKV (Matroska Video) is a flexible, open-source video format used for high-definition videos. It supports various video and audio qualities and is the basis for the WebM format, which provides high-quality, free video.

MP4 (MPEG-4) is a popular video format that is known for its broad compatibility and efficient performance. It compresses videos without losing quality, which makes MP4 files easy to transfer and play on most media players.

Here’s a side-by-side look at MKV and MP4:

Do You Really Need to Convert?

Before getting into conversion instructions, check if it’s necessary. If your video is already in MP4 format, you’re in luck! MP4 is widely supported and compatible with most devices and media players. Instead of converting, you might only need a reliable tool to download or manage your videos.

How to Change MKV to MP4 Online 

ConvertFiles is a free, easy-to-use online tool for converting MKV files to MP4. You don’t need to download anything — just use your browser. To convert:

1. Upload your MKV file.
2. Choose MP4 as the format.
3. Click Convert.

This tool also supports converting audio, image, and document files.

Zamzar is another free tool you can use. This online service supports over 1,200 file formats, including MKV, AVI, WMV, and MOV.

The conversion process is quick, usually finishing in just 1-2 minutes, though it can take up to 10 minutes for larger files. If you’re unsure how to convert MKV to MP4, Zamzar's interface provides easy-to-follow instructions.

Is MKV Better Than MP4?

It depends on what you care about most.

MKV is a great choice if you want to keep the highest quality in your videos, even though the files can be larger. MP4, on the other hand, is better for smaller file sizes and easier sharing while still maintaining good quality.

Read also: How to Convert a Video to Audio: 9 Safe & Reliable Ways

How to Convert MKV to MP4 on Mac and Windows

If you have a lot of files to convert or if your file is too large for an online tool, consider using a desktop application. Movavi Converter is a good choice for handling audio, video, and image formats:

1. Download Movavi Converter for your Windows or Mac computer. 
2. Open the installer and follow the instructions. Once installed, the app will launch automatically.
3. Find the MKV files you want to convert and drag them into the program’s window. You can add multiple files at once for batch conversion.

4. In the Formats menu, select MP4 as the output format. You can also adjust settings like bitrate, resolution (including HD, Ultra HD, and 4K), and codec. Look for the SuperSpeed label for quick conversion without quality loss.

5. Click the Save To button to choose an output folder. 
6. Hit the Convert button to start the process. Your converted files will be saved to the chosen folder.

If you need another reliable way to convert MKV to MP4, EaseUS Video Converter is a solid option:

1. Download and launch EaseUS Video Converter on your PC. 
2. Click Video Converter and then Choose Files to add your MKV video. You can also drag and drop the video into the program.

3. Click Settings and select MP4 as the format. You can also adjust the resolution and quality if needed.
4. Choose where you want to save the MP4 file. 

5. Click Convert to convert one video or Convert All to handle multiple videos at once.
6. Go to the Finished tab to see your converted MP4 file. Click Open to preview it with the built-in media player.

Read also: How to Download Audio from YouTube on Mac: 8 Ways (Free & Paid) + 2 Bonus Ways

Bonus Option for PC: VLC Media Player

VLC is a free, open-source media player that handles almost every audio and video format, including MKV. If you already have VLC installed, you can use it to play MKV files without conversion.

But if you still need to convert your MKV file to MP4, VLC can help with that too. Here’s how to use VLC for that:

1. Open VLC Media Player on your computer.
2. Click on Media in the menu and select Convert/Save. You can also press Ctrl + R to open this option.
3. Click the Add button to select your MKV file.

4. After adding the file, click Convert/Save.

5. In the Convert window, choose Video – H.264 + MP3 (MP4) from the Profile dropdown menu.
6. Click Browse to choose where to save the converted file and enter a new name if needed.
7. Click Start to begin the conversion process. You can track progress in VLC’s timeline.

Keep in mind that while VLC’s conversion feature is useful, it might be slow and sometimes produce files with issues like missing audio or reduced quality.

Can You Convert MKV to MP4 by Renaming the File?

No, renaming an MKV file to MP4 only changes the file extension, not the actual video format. This means the video’s codec, resolution, and other details remain the same. If the MKV file uses newer standards like HEVC, it won’t play correctly after renaming. 

To convert the file properly, use a video converter. It’s a straightforward process, so there’s no need to skip it.

Is It a Good Idea to Convert Videos on a Mobile Device?

For small files or quick conversions, mobile apps can be useful. For larger or more complex conversions, a desktop or online tool is much more effective.

Here are some drawbacks:

• Mobile devices usually have less processing power, which makes the conversion slower.
• Managing large video files is challenging due to limited storage and memory on mobile devices.
• Mobile apps don’t provide as many features or customization options as desktop software.
• Video conversion is resource-intensive and will quickly drain your phone’s battery.

How to Convert MKV Files to MP4 in OBS

Many streamers save their broadcasts locally to upload or archive later. Often, these recordings need to be in MP4 format. However, if OBS crashes before saving the file, it might become corrupted. To avoid this, you can record in FLV or MKV formats and then convert them to MP4.

Here’s how to do it:

1. Open OBS Studio.
2. Go to the File menu and choose Remux Recordings.
3. In the window that appears, select your MKV or FLV file by clicking the three dots.
4. Click Remux to convert the file to MP4. The new MP4 file will be saved in the designated folder.

Can Any Video Converter Change MKV to MP4?

No, not every video converter is good for MKV to MP4 conversion. Some converters don’t support MKV or might not do the best job with the conversion. It’s best to stick with the converters we recommended earlier.

Final Words

Hopefully, this clears things up. If you need to convert MKV to MP4 to make your videos work on different devices or to reduce file size, choose the converter from the options listed here — ConvertFiles, Zamzar, Movavi, EaseUS, or VLC Media Player.