WMV to MKV Converter

Move a Windows WMV into an open MKV container that can carry several audio tracks and subtitles. Free, in your browser, with no signup.

Select WMV file →

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We support most file types including: MP4, MOV, WEBM, AVI, MP3, WAV, PNG, JPEG, GIF, MKV, PDF, FLAC, TIFF!

EchoWave is used by creators, marketers, educators, and businesses to convert and edit media online.

Updated July 2026

MKV is an open Matroska container that can hold several audio tracks and subtitle tracks in one file, which a Windows Media WMV cannot. Converting WMV to MKV is the move when you want a flexible file for VLC, a home media server, or a library where dubbed audio and captions live alongside the video. EchoWave converts it free in your browser, with no signup.

Free, no sign-upNo account, no trial

Runs in your browserNothing to install

Works on every devicePhone, tablet, laptop

No watermarkClean output, every time

How it works

How to convert WMV to MKV

1
Upload your WMV
Drag your WMV onto the converter or pick it from your device. Nothing to install.
2
Choose MKV and convert
Select MKV as the output and start. Free, with no sign-up and no watermark.
3
Download your MKV
Save the finished MKV, or open it in the editor to trim, crop, or resize it first.

Try it

Estimate your MKV

Pick a video bitrate and a length to see the MKV file size before you convert.

Video bitrate

Length5 min

1 min30 min

Estimated MKV size183MBSharp 1080p

An estimate. Real size varies with resolution, frame rate, and how much the picture moves.

The formats

WMV vs MKV

WMV

Windows Media Video

Windows Media video, small and Windows-first

Type: Windows Media video
Holds: Windows Media video with WMA audio
Typical size: Small, built for Windows
Plays on: Windows Media Player and VLC

Best for:Older Windows video and slideshows

MKV

Matroska Video

An open container that holds almost anything

Type: Open video container
Holds: Almost any codec, plus several audio and subtitle tracks
Typical size: Large, depends on the codec inside
Plays on: VLC and most modern players, less on default phone apps

Best for:Movies with multiple audio tracks and subtitles

Will it lose quality?

When the codecs already match MKV, the converter can change the container without re-encoding, so the picture stays identical.
When the video has to be re-encoded for MKV, a high bitrate keeps it visually close to the WMV.
Converting cannot add detail the WMV never had. The output is at best as good as the source.

Use cases

What people use it for

Play anywhereMake a clip your device supports

Video editorsGet footage your software accepts

Web videoUse a format browsers play

CourseworkHand in a standard video file

SharingSend a clip people can open

Troubleshooting

If something looks off

The MKV will not play

Some players are picky about codecs. Try it in VLC, which opens almost anything, or convert again and let the converter re-encode the video.

The file got larger

A format change can shift the size, and re-encoding at a high bitrate adds overhead. Lower the bitrate or trim the clip for a smaller file.

Audio and video drift out of sync

Re-download the source and convert again. If a long recording drifts, splitting it into shorter pieces usually fixes the sync.

FAQ

WMV to MKV questions

Why convert WMV to MKV?

MKV is an open container built to hold multiple audio tracks, multiple subtitle tracks, and almost any codec in a single file. WMV is a closed Windows Media format with none of that flexibility, so MKV suits VLC, media servers, and tidy video libraries far better.

Is the WMV to MKV converter free?

Yes. EchoWave converts WMV to MKV with no signup, no trial, no watermark, and no file-count limit on these pages. Upload your video, convert it, and download the MKV from your browser.

How do I convert WMV to MKV?

Upload your WMV, choose MKV as the output format, and start. When it finishes, download the MKV or open it in the editor to trim, crop, or add captions first.

Will converting WMV to MKV lose quality?

WMV uses Windows Media video, so it is re-encoded for MKV rather than simply rewrapped. A high bitrate keeps the picture close to the original. Converting cannot add detail the source WMV never had.

After converting WMV to MKV, what plays the file?

VLC plays MKV on every platform, and most modern media players and TVs handle it too. Default phone apps and QuickTime are less reliable with MKV, so convert WMV to MP4 instead if you need the widest device support.

Can I keep multiple audio tracks or subtitles?

MKV is designed to carry several audio and subtitle tracks together. A single WMV usually contains one audio track, but MKV is the right destination when you plan to add dubbed audio or caption tracks later in an editor.

Does the WMV to MKV converter work on Mac, Windows, and Linux?

Yes. The converter runs in any browser, so you can turn WMV into MKV on macOS, Windows, Chromebook, Linux, and mobile with nothing to install. To watch the result, VLC is the safe choice across all of them.

Can I convert large WMV files or several videos to MKV?

Nothing limits how many WMV clips you queue, so process them one after another and build out your Matroska library at your own pace. A feature-length WMV bound for an MKV on a home media server is fine; it just spends a bit longer uploading and re-encoding than a short clip would.