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How to Convert MKV to MP4? 4 Methods and 9 Video Converters Recommendations

Takashi Originally published Mar 01, 24, updated Mar 20, 24

How to Convert MKV to MP4? 4 Methods and 9 Video Converters Recommendations

Converting MKV files to MP4 format can greatly enhance compatibility and accessibility across various devices and platforms. With an array of methods and video converters available, the process becomes straightforward and efficient. Let's delve into four effective methods and nine top-notch video converter recommendations to seamlessly transform your MKV files into MP4.

In this article
  1. Why Convert MKV to MP4?
  2. Steps on Using MKV to MP4 Converters
  3. Best MKV to MP4 Converters
  4. Limitations of MKV to MP4 Converter Online
  5. Free vs. Paid MKV Video Converter
  6. Steps on How to Add Subtitles to MKV Video Using Uniconverter Ultimate
  7. FAQs About MKV to MP4 Conversion

Why Convert MKV to MP4?

There are several reasons you might need to convert MKV files to MP4 online or through other methods. Here are some common scenarios:

MKV format not supported: Often, MKV files won't play on certain devices or players due to compatibility issues. Converting them to MP4, a more widely supported format, solves this problem.

Freeing up space: MKV files tend to be large and can take up significant storage space. Converting them to the smaller MP4 format can help you reclaim space on your device.

Ease of sharing: MKV files, being large, can be challenging to share, transfer, or stream online. Converting them to MP4 simplifies the sharing process, especially on social media platforms and video sharing websites.

Steps on Using MKV to MP4 Converters

In this part
  1. Method 1: Using Uniconverter Ultimate
  2. Method 2: Using Wondershare Free Video Converter
  3. Method 3: Using Handbrake
  4. Method 4: Using FFmpeg

Method 1: Using Uniconverter Ultimate

Step 1 Launch Wondershare MKV converter and load MKV files.
load MKV files to this Mac MKV converter

Launch this MKV to MP4 converter on your Mac. Drag and drop the desired MKV files on your software interface. Alternatively, you can also add the files by clicking Add Files.

Step 2 Select MP4 as the output format.
Convert MKV to MP4 - Select MP4 as the output format

Once the MKV files are added to the software interface, select MP4 as the output format from the Video category.

Step 3 Edit the MKV videos (optional).
Edit MKV Videos

Videos can also be edited or customized if needed. For this, hit one of the editing icons under the video thumbnail to enter the editing window, as this step is totally optional, you can skip it and also move onto the next step. Learn more about editing MKV videos >.

Step 4 Convert MKV to MP4 on Mac.
Convert MKV to MP4 on Mac

Finally, hit Start All button to start the MKV to MP4 conversion process. Your MKV files will be successfully converted to MP4 without any loss of quality. After the conversion, you can click Export > Uploading to Vimeo to share your converted MKV files to Vimeo directly. Also, you can transfer MKV files to your iPhone/Android devices by UniConverter.

Method 2: Using Wondershare Free Video Converter

convert MKV to MP4 with subtitles by Wondershare Free Video Converter
Step 1 Launch the Application and click on the central Folder icon or drag and drop your file to open it inside the software.
Step 2 When your file has opened up, click on Target, and then select the MP4 format. After this, click on the Add Subtitles on the drop-down. This will open a file explorer where you will select your subtitles file.
Step 3 Click on the Convert button to begin the conversion. When the conversion finishes, your files will appear in the Converted tab from where you can view it.

Method 3: Using Handbrake

HandBrake is a free, multi-platform video transcoder offering easy conversion to MKV or MP4 formats with features such as cropping, resizing, and artifact removal. However, certain sought-after functionalities are not supported:

  • Lossless MKV to MP4 Conversion: HandBrake re-encodes files, resulting in quality loss.
  • Batch Conversion: Only sequential processing is supported; no simultaneous batch conversion.
  • Joining MKV Files: HandBrake lacks the capability to merge multiple MKV clips.
  • Limited Output Formats: Only MKV and MP4 formats are supported for conversion; no support for AVI or other formats.
convert MKV to MP4 with subtitle by HandBrake

Supported Input Formats: HandBrake accommodates most multimedia, DVD, and Blu-ray files that aren't copyright-protected.

Supported Output Formats: HandBrake outputs in MKV or MP4 containers, with various video and audio encoders supported, including x265, x264, MPEG-4, VP8, VP9, AAC, MP3, Flac, AC3, Vorbis, and pass-through for certain audio tracks.

Step 1 Download, install, and open HandBrake software on your computer. Click the Source button and choose Open File option that will allow you to add the MKV files from your system that you want to convert.
Step 2 Under Output Settings, select MP4 as the desired target format.
Step 3 To compress MKV HandBrake and to reduce the file size, you can edit the bit rate or the frame of the output file.
Step 4 Click on the green Start button to convert MKV to MP4 HandBrake one by one.

So if you're looking for an alternative to HandBrake, Wondershare UniConverter (originally Wondershare Video Converter Ultimate) will be your best choice as it not only provides you so many functions but also best output quality and super fast converting experience.

Method 4: Using FFmpeg

The best way to convert MKV to MP4 is an easy one: copy the existing video, audio, and subtitle streams and place them all into a new container, which will serve as the new save point.

This avoids any encoding task altogether, which means you’ll have no issue with quality, and it’s also relatively quick because it won’t require much CPU power - only disk write speed.

Here are the steps to convert MKV to MP4 with FFmpeg

Step 1 Access FFmpeg through the Command Prompt utility.
Step 2 Enter the following command to convert the MKV video:

ffmpeg -i video.mkv -c copy video.mp4

Step 3 For batch conversion, place all the MKV videos into a single directory, and enter the command stated below, which will turn the files into MP4 without changing the file names:

for /R %f IN (*.mkv) DO ffmpeg -i "%f" -c copy "%~nf.mp4"

Best MKV to MP4 Converters

In this part
  1. CloudConvert
  2. FreeConvert
  3. VLC
  4. Freemake
  5. AConvert
  6. FreeFileConvert
  7. MacX Video Converter Pro
  8. Winx HD Video Converter
  9. iMedia Converter Deluxe

1. CloudConvert

CloudConvert can be used by anyone looking for an easy way to convert MKV files to MP4 on the go. This tool simplifies your file conversion process, so you don’t have to waste time trying to convert your personal media collection using complicated and time-consuming software.

mp4 to mkv online converter


  • Maintains file quality
  • It also supports uploading files from Google Drive, Dropbox, OneDrive, and URL


  • Compatible with only MP4, WebM, AVI, MOV, and WMV formats.

2. FreeConvert

It is a safe and handy online tool to complete MKV file conversion using any modern browser. Besides adding the videos from your computer storage, you can also add media from cloud services, such as Google Drive and Dropbox.



  • It can convert 1GB files for free
  • 256-bit SSL encryption


  • Too many ads
  • Slow processing
  • Non-existent customer support


3. VLC

VLC is not only a familiar media player but also a useful platform to convert MKVs to MP4 videos without any hassle. You can easily access VLC on your Windows and macOS desktop.



  • Free


  • Not a full-time file converter
  • Limited format support
  • Complicated process to convert files

4. Freemake

If you want to convert the MKV file to play it on any specific device, then the Freemake tool is an excellent choice. It supports every format in the book and can also edit media files.



  • The tool supports 500+ file formats
  • Free-to-use


  • Only available on Windows

5. AConvert

This is one of the popularly used MKV to MP4 online converter free to use and allows conversion with editing features. The program allows adding a local file and its URL and supports an array of popular formats for conversion. AConvert also allows customizing files by changing its frame rate, bit rate, and file size. Once the file is converted, it can be downloaded from the link at the program interface. The video aspect of the file with respect to its height and width can also be changed.

mp4 converter online AConvert

6. FreeFileConvert

FreeFileConvert is another popularly used online MP4 to MKV converter online that needs no software download or installation. Files can be added to the program interface from PC, URL, Google Drive, and Dropbox. The converter supports an array of video, archive, documents, video, and other format types. Once the files are converted, they can be easily downloaded from the link at the converter interface. The program has a simple-to-use interface and allows adding a maximum of 5 files with 100MB in size.

mkv converter online FreeFileConvert

7. MacX Video Converter Pro

This is an all-in-one Mac video converter that can help you record, edit, convert, and download videos through exceptional format compatibilities such as VOB, MOV, WMV, AVI, MP4, MKX, and many other formats. You can also enjoy QuickTime and iTunes while editing videos via iMovie or Final Cut Pro. You can also share videos on YouTube as well as Facebook or paly using your iPad Mini, iPhone, HTC, or other mobile devices. The Intel QSV component is newly developed to accelerate tech features for faster conversion speed. Using this converter, you can download music and videos from over 300 websites and convert them to any format you like. The advantages of this include a user-friendly and sleek interface, solid compatibility for more than 320 audio and video formats. However, this is also too expensive for common users, and there’s no discount provided when buying the converter online.

MacX Video Converter

8. Winx HD Video Converter

For Mac users out there, this is another good option when it comes to converting MKV to MP4, AVI, or other file formats on Mac. This is comprehensively featured with HD video quality conversion to provide Mac users with stress-free video conversion methods. It can convert Blu-ray, 4k UHD, HDTV/HD camcorders, MKV, MPEG, and other video file formats for easy viewing. The advantage of using this is that it supports multiple formats, easy to use interface, good quality, and fast speed. The disadvantage lies in that it costs too much and is complicated when editing files.

WinX HD Video Converter

9. iMedia Converter Deluxe

Mac users can take advantage of the MKV file converter since it helps in converting MKV to MP4 or other video formats on Mac within a few clicks. All you need to do is download the video, edit it, set the output format or location, convert the file, and share it. It continuously adds new formats to ensure quality video conversion for Mac users. The advantages include the simple conversion process and downloading of videos and burn them into DVD format. When it comes to disadvantages, there’s not much customization for the DVD burning menu template.

Limitations of MKV to MP4 Converter Online

MKV converter online is definitely a pocket-friendly and simple way of file conversion. But on the flip side, the method also has its share of associated cons, which cannot be ignored. Listed below are some of the limitations for MKV to MP4 Converter Online.


  1. Dependent on Internet connection


MKV converter online works directly through the browser and is thus dependent upon your Internet connection's availability and speed. These converters cannot work offline, and thus you need to be connected to a strong internet connection for a fast conversion.


  1. Limited features:


Most of the MKV to MP4 online converters are free to use and thus have limited features. You can use these converters for basic conversion needs, but if you are looking for advanced options, these online tools are not the right choice.


  1. File size limitation


Most of the tools to convert MKV to MP4 online have a limitation to file size uploaded to the program interface for conversion. So these converters are good only if your file size is small.


  1. Need to add and download the file again and again


When you convert MKV file to MP4 online, you have to add individual files at a time as most of the converters do not support batch processing feature. Moreover, after every process, the converted file needs to be downloaded, a time-consuming process.


  1. Slow conversion speed


MKV to MP4 online converters are slow in conversion. These tools may take a lot of time to upload and then convert your desired files. So if you are looking for some fast solution, then these tools are not the apt choice.

Free vs. Paid MKV Video Converter

As we list above, there're various paid and free MKV converter Mac available online for your selection. With free MKV video converter tools, you don't need to worry about the money loss caused by paid converters, but the potential damage to the video quality can't be ignored. Below is a general comparison between free and paid MKV video converters Mac convert MKV to MP4, MOV, etc.


Free MKV Mac Converter Online

Paid Video Converter Software

Supported Format

Only popular formats like MP4, MP3, MOV, WMV, etc.

Support over 1000 audio/video formats including MKV, AVI, AVCHD, and more.

Conversion Speed


Fast and efficient

File Limitation

Free convert up to 100MB and charge for larger files.

No limitation for file conversion.

Output Video Quality

Damaged or lost video/audio quality


Network Connection



Ad/Malware Free

No, full of ads instead

Yes, clean and secured

Steps on How to Add Subtitles to MKV Video Using Uniconverter Ultimate 

Step 1 Import the MKV video file.
open Wondershare Subtitle Editor

On Wondershare UniConverter, click to select the Video Editor category from the navigation pane that is present in the left of the interface. From the right window, click the Subtitle, and from your local computer, select and import the MKV video file you want to add the subtitles to.

Step 2 Add the subtitles-SRT file to the video.
convert mkv to mp4 with subtitle - add subtitle

When the subtitle window opens up, stretch the Subtitles menu at the top-right section, and hit on the Add button, select and import the SRT file with the correct format to UniConverter.

Step 3 Personalize/Customize the content of the subtitles.
convert mkv to mp4 with subtitle - edit subtitle by Wondershare Subtitle Editor

Once the subtitles appear below the preview window, you can customize the subtitle font type, its size, and color, along with other attributes like bold, italics, and underline using their corresponding options present under the Font section. Also, the Outline Width drop-down list and the Transparency slider allow you to customize the stroke width and the opacity level of the text. If you want to change the area where the subtitles should appear on the screen, i.e., at the top, middle, or bottom, you can click the relevant button present under the Position section to get this done. Once everything is set up, click the OK to save the changes, and to get back to the previous window.

Note: If you want to modify the content of the subtitle or gain more editing controls, you would better move to the Toolbox > Subtitle Editor section, where you are able to use the Start Time and End Time fields to adjust the duration the text should appear on the screen.

Step 4 Define output preferences and convert to MP4.
choose output as MP4

Click to open the Output Format menu from the bottom, go to the Video tab, select the MP4 from the left pane, and pick your preferred resolution preset from the right. Optionally, use the File Location field to specify an output folder, and click the Save to convert the MKV video to MP4 with subtitles.

FAQs About MKV to MP4 Conversion

What is the difference between MKV and MP4 file format?

MKV and MP4 are multimedia container formats. MKV, or Matroska, is an open standard capable of holding various types of media in a single file, supporting multiple codecs and streams. MP4, or MPEG-4, is widely used and versatile, accommodating video, images, audio, subtitles, and more in a single file. While both are used for audio and video playback, their differences lie in supported codecs and compatibility with portable devices, where MP4 generally fares better.

How to convert HD MKV files for iTunes without quality loss?

Major formats like MP4, M4V, MOV, and others are supported by iTunes. Thus the best way to convert MKV to iTunes is by converting it to an iTunes compatible format like MP4. In such situations, a good MKV to MP4 converter for Mac will be an ideal choice.

What is needed to convert MKV to MP4 on Apple or Mac device?

Though the MKV file format is supported by Apple products, but sometimes, the codecs present in the file are not supported. In such a scenario, the need arises to convert the MKV file to a more device-friendly and compatible format like MP4.

How to convert multiple MKV files to MP4 format (batch conversion)?

If there are multiple MKV files that you need to convert to MP4 file format, then you need a professional file converter with a batch conversion facility. One such decent program is Wondershare UniConverter (originally Wondershare Video Converter Ultimate) which allows adding multiple files at a time and converting them to the desired format within no time.

How to convert MKV to MP4 on Mac without losing quality?

Various online programs and professional software facilitate seamless file conversion between popular formats like MKV and MP4, ensuring no compromise on quality. For instance, UniConverter (formerly Wondershare Video Converter Ultimate) offers 30x faster conversions without sacrificing quality. If you seek efficient conversion of multiple MKV files to MP4 on Mac, UniConverter is a reliable option.

Why is there no audio after converting MKV to MP4 using FFmpeg?

If the audio format is not in MP3 or AAC format, you could be facing no sound issue after converting MKV to MP4 with FFmpeg. However, in that case, we recommend converting the audio to MP3 or AAC before changing the video format.

Why does FFmpeg lose video subtitles after converting MKV to MP4?

As a container format, most MKV files keep the subtitle files inside them. Therefore, before converting MKV to MP4, you should save the exact name of the subtitle as the video file. If you do not perform the said activity, the subtitle may get lost.

How do I convert MKV to MP4 on Mac for free?

To convert MKV to MP4 on Mac for free, Wondershare Free Video Converter for Mac is the best choice. The steps for the conversion using the tool are as follows.

  • Download, install and open the software on your Mac. Add the MKV videos at the Convert tab by simply dragging and dropping or by clicking on the + Add Files button.
  • At Convert all files to: section at the right corner, choose MP4 as the desired target format.
  • Select the destination folder at the Output section on the bottom-left corner.
  • Finally, click on the Convert All button to start the conversion.

Can Mac open MP4 files?

Yes, if the codecs are compatible, Mac can open and play MP4 files. Since there are multiple codecs associated with MP4 format, there are high chances that the ones which are used for encoding the video is not compatible with Mac and thus the file will not open. In such situations, you would need to either use a compatible player or convert MP4 to a compatible format. Learn more details about how to open MP4 on Mac.


By employing these methods and utilizing the recommended video converters, you'll effortlessly convert MKV to MP4, ensuring smooth playback and compatibility across your devices.

Takashi Mar 20, 24
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