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Wondershare UniConverter

  • Convert FLV to MKV, MP4, MOV, and other 1000+ video/audio formats.
  • Download or record videos from 10,000+ video sharing sites.
  • 30X faster conversion speed than any conventional converters.
  • Burn and customize your DVD with free DVD menu templates.
  • Versatile toolbox combines screen recorder, GIF maker, fixing video metadata, etc.
convert FLV to MKV


1. Play MKV on Device+
  1. 1.1 Top MKV Player
  2. 1.2 Play MKV on Mac
  3. 1.3 Play MKV on Apple TV
  4. 1.4 Play MKV on Samsung TV
  5. 1.5 Play MKV on Sony TV
  6. 1.6 Play MKV on LG TV
  7. 1.7 Play MKV on PS3
  8. 1.8 Play MKV on Xbox One
  9. 1.9 Play MKV on Xbox360
  10. 1.10 Play MKV to iPhone
  11. 1.11 Play MKV to iPad
  12. 1.12 Play MKV on iPod
  13. 1.13 Play MKV on Android Phone
  14. 1.14 Play MKV in VLC
  15. 1.15 Play MKV in Windows Media Player
  16. 1.16 MKV Playback Issues in VLC
2. Convert MKV to Other Format+
  1. 2.1 Convert MKV to MP4
  2. 2.2 Convert MKV to MP4 on Mac
  3. 2.3 Convert MKV to MP4 Online
  4. 2.4 Convert MKV to MP3
  5. 2.5 Convert MKV to Audio
  6. 2.6 Convert MKV to WMV
  7. 2.7 Convert MKV to M4V
  8. 2.8 Convert MKV to AVI
  9. 2.9 Convert MKV to AVI Online
  10. 2.10 Convert MKV to FLV
  11. 2.11 Convert MKV to DVD
  12. 2.12 Convert MKV to MOV
  13. 2.13 Convert MKV to iTunes
  14. 2.14 MKV to MOV Converter Online
  15. 2.15 Convert MKV to VOB
  16. 2.16 Convert MKV to DivX
  17. 2.17 Convert MKV to MPEG
  18. 2.18 Convert MKV to MPEG2
  19. 2.19 Convert MKV to MPEG4
  20. 2.20 Convert MKV to XviD
  21. 2.21 Convert MKV to 3GP
  22. 2.22 Convert MKV to M2TS
  23. 2.23 Convert MKV to H264
  24. 2.24 Convert MKV to TS
  25. 2.25 Convert MKV to VCD
  26. 2.26 Convert MKV to AC3
  27. 2.27 Burn MKV to DVD
  28. 2.28 Burn MKV to Blu-ray
  29. 2.29 Convert MKV to SWF
  30. 2.30 Convert MKV to MP4 with Subtitle
  31. 2.31 Convert MKV to WAV
  32. 2.32 Convert MKV to MPG
  33. 2.33 Convert MKV to ISO
  34. 2.33 Convert MKV to WebM
3. Convert Other Format to MKV+
  1. 3.1 Convert MP4 to MKV
  2. 3.2 Convert MP4 to MKV on Mac
  3. 3.3 Convert MP4 to MKV Online
  4. 3.4 Convert M4V to MKV
  5. 3.5 Convert WMV to MKV
  6. 3.6 Convert MOV to MKV
  7. 3.7 Convert DVD to MKV
  8. 3.8 Convert M2TS to MKV
  9. 3.9 Convert AVI to MKV
  10. 3.10 Convert Bluray to MKV
  11. 3.11 Convert FLV to MKV
  12. 3.12 Convert AVCHD to MKV
  13. 3.13 Convert OGM to MKV
  14. 3.14 Convert MTS to MKV
  15. 3.15 Convert WTV to MKV
  16. 3.16 Convert VOB to MKV
  17. 3.17 Convert RMVB to MKV
  18. 3.18 YouTube to MKV
  19. 3.19 Convert WebM to MKV
4. Edit MKV & Other Tips+
  1. 4.1 Extract Subtitles from MKV
  2. 4.2 Add Substitles to MKV
  3. 4.3 Add SRT to MKV
  4. 4.4 Compress MKV Video
  5. 4.5 Reduce MKV File Size
  6. 4.6 Cut MKV Files
  7. 4.7 Edit MKV Metadata
  8. 4.8 MKV No Sound
  9. 4.9 MKV Video Player for Android
  10. 4.10 MKV Converter for Mac
  11. 4.11 Free MKV Converter
  12. 4.12 MKV Player Mac
  13. 4.13 2D to 3D MKV Converter
  14. 4.14 Remux MKV
  15. 4.15 MKV Encoder
  16. 4.16 Convert MKV to FCP Mac
  17. 4.17 Stream MKV to TV with Chromecast
  18. 4.18 Import MKV to iMovie
  19. 4.19 Windows DVD Maker MKV
  20. 4.20 Convert MKV to MP4 with HandBrake Alternative

FLV to MKV Converter-How to Quickly Convert FLV to MKV

by Christine Smith • 2020-11-20 17:12:03 • Proven solutions

Are you exhausted looking for the best FLV to MKV converter? Yes, the lack of know-how can really eat into your nerves. However, do not fend off because here is your ultimate fix. This article explores practical and seamless ways to convert FLV to MKV, of course, using the best FLV to MKV converter.

Part 1. Most Recommend Way to Convert FLV to MKV on Windows/Mac

Are you a Windows or Mac user and desperate for the best FLV to MKV converter? Wondershare UniConverter is the tool you have always been looking for. This FLV to MKV converter has an array of unmatchable features specially tailored to take your conversion to another level. The output quality, speed, elegant interface, device compatibility, and support of batch conversion are a few among the pinnacle features. With millions of users around the globe making it an indispensable tinker program, you wouldn’t be wrong at all if you chose it. Download today and transform your conversion into the top level.


Wondershare UniConverter - Your Complete Video Toolbox

  • Best video converter to convert FLV to MKV files in any format with 30X faster speed and high-quality output.
  • Support the most popular video and audio formats, including FLV/MKV/AVI/MP3/WAV/M4A/M4B and more.
  • Download files from 10,000+ websites like YouTube by pasting URLs.
  • Easily transfer files from Mac/PC to iPhone/iPad/Android devices without any quality loss.
  • Burn MKV files to DVD with free templates, super burning speed, and high-quality output.
  • Additional functions include Fixing Media Metadata, video compressor, GIF Maker, Screen Recorder, and DVD Copy.

Step 1 Import FLV Files in FLV to MKV in Wondershare UniConverter.

Install and launch Wondershare UniConverter on your PC. On the top left of the primary window, click on the +Add Files icon and select a suitable file upload option. Alternatively, you can drag the target FLV files and drop them directly on the main window.

add FLV files to the FLV to MKV converter

Step 2 Choose MKV as Output Format.

When the FLV files have been successfully uploaded, hit the Setting icon. Go to the Video category and select the MKV as your target output format.

choose MKV format for FLV to MKV conversion

Step 3 Convert FLV to MKV.

When everything is okay for you, just hit the Start All. However, if your interest is individual conversion, then click the Convert beside each video and wait.

convert all FLV to MKV by Uniconverter

Part 2. Top 5 FLV to MKV Converters Online

There is plenty of online FLV to MKV converters available, but getting the best converter for your task can be daunting. Here, we have selected for you the top 5 FLV to MKV converters, which can effectively handle your FLV to MKV conversion.

1. Online FLV to MKV UniConverter

Online FLV to MKV UniConverter is an excellent FLV to MKV converter online. Its simplicity and support to an array of different media file formats is a good highlight. It offers several quality outputs like extreme, normal, high, and lower.


  • It is a free program.
  • It features a simple and straightforward interface.
  • It supports a variety of input formats, including popular ones.
  • You can choose the desired output quality raging from lower to extreme options.


  • Limited features.
  • Limited output formats.

convert MKV to FLV online by Online FLV to MKV Uniconverter

2. Aconvert

Aconvert is a simple yet functional FLV to MKV converter online. The conversion process is quite simple, as it involves a few clicks. Users can adjust audio bitrate and sample rate depending on their need before hitting the Convert button. It is a free tool that is worth giving a try.


  • Simple and easy to use interface.
  • Users can adjust the frame rate and sample rate to enhance their output.


  • Limited features.
  • File size limit of 200MB.

convert MKV to FLV online by Online FLV to MKV Aconvert

3. Cloudconvert

Cloudconvert is an all-round FLV to MKV converter online with excellent functionalities. You can convert your file with simple clicks and no effort at all. Users can select files from computers, URL, Dropbox, Google Drive, and OneDrive.


  • Supports cloud conversion.
  • Supports several formats.


  • Slow Conversion.
  • Reported occasional outage.

convert MKV to FLV online by Cloudconvert

4. Convertio

Convertio is one of the top online MKV to FLV converters. The free converter supports a wide range of input and output format and is thus not only good for MKV and FLV but also several other conversions.


  • Simple and straightforward interface.
  • No registration is required.
  • Supports a variety of output and input formats.


  • File size limit of 100MB.
  • Limited features.

convert MKV to FLV online by Convertio

5. Onlineconvertfree

This is no doubt one of the big online names for MKV to FLV conversion. The simple yet useful program is worth giving a try. The conversion process involves file upload, choosing the output format, and clicking the conversion button. Once the file is converted, you just click the download button and get it on your device.


  • Easy to use.
  • It is free to use.
  • No registration is required.


  • Reported cases of slow and lengthy conversion.
  • Only support a few and popular formats.

convert MKV to FLV online by Onlineconvertfree

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