Add your MP4 file
Drop one or more .mp4 files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
MP4 to WMV
Pulling the soundtrack out of a .mp4 video into .wmv audio keeps what you can hear and drops the picture entirely. Free, private, and validated — the file never leaves your browser.
Private for supported formats — processed in your browser
Runs on your deviceConvert supported files
Drop MP4 files here
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.About converting MP4 video to Windows Media video
Pulling the soundtrack out of a .mp4 video into .wmv audio keeps what you can hear and drops the picture entirely. An .mp4 file is a multimedia container that bundles compressed video, audio, subtitles, and chapter data into a single stream-friendly package. It is the default delivery format for nearly every phone, camera, and video platform, which makes .mp4 the safest target when a clip has to play everywhere.
A .wmv file contains Windows Media Video, Microsoft's proprietary codec family, almost always wrapped in an ASF container. The extension was everywhere on Windows XP-era PCs, from downloaded clips to Movie Maker exports, but it has faded as MP4 became universal. For this route the practical draw is excellent support across legacy Windows software and vC-1 encodes hold up reasonably well for their age — balanced against effectively abandoned by Microsoft itself, which is worth knowing before you commit a large batch.
Why convert MP4 to WMV?
The usual reason to take .wmv audio out of a .mp4 file is that only the sound matters — a talk, interview, song, or podcast segment. Keeping the video stream would waste storage, and a dedicated audio file is easier to trim, tag, and play. On the source side, fewer track, attachment, and chapter features than Matroska; on the target side, the payoff is excellent support across legacy Windows software, which is exactly what you want for playing old Movie Maker projects and family archives.
MP4 vs WMV at a glance
| Aspect | MP4 video (.mp4) | Windows Media video (.wmv) |
|---|---|---|
| Format type | Container — quality depends on the codecs and settings inside | Container — quality depends on the codecs and settings inside |
| How it stores data | typically carries H.264/AVC or H.265/HEVC video with AAC audio, though the box structure also accepts AV1, MP3, and timed-text tracks | aSF container carrying WMV1, WMV2, or WMV3 (VC-1) video, typically with WMA audio |
| Strongest at | publishing video to the web, social media, or a client who has not specified a format | playing old Movie Maker projects and family archives |
| Weak spot | fewer track, attachment, and chapter features than Matroska | effectively abandoned by Microsoft itself |
| Metadata | iTunes-style metadata atoms (title, artist, cover art) plus XMP and per-track language tags; ID3 is not native to the container | aSF content-description attributes hold title, author, copyright, and rating fields, plus extended attributes used by Windows Media Player libraries |
Pick WMV as the output
Select .wmv in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if WMV is selectable, the route is real and validated.
Convert on your device
Press Convert. A WebAssembly FFmpeg build demuxes the audio track and re-encodes it locally; the video stream is simply discarded.
Verify and download
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid WMV file. Outputs keep the original filename with the .wmv extension.
MP4 to WMV questions, answered
Will converting MP4 to WMV lose quality?
Since mp4 is container-oriented and wmv is container-oriented, the conversion preserves the source content exactly as stored; no additional compression pass is applied beyond what .wmv itself requires.
Is it private to convert MP4 files here?
Yes — the .mp4 file is processed inside your browser tab and never uploaded. A WebAssembly FFmpeg build demuxes the audio track and re-encodes it locally; the video stream is simply discarded. Close the tab and the file is gone from memory.
Where will the WMV file work?
Windows 10 and 11 still play .wmv out of the box, but macOS dropped support after the QuickTime plugin era ended, and no browser or mobile OS will touch it. Conversion to MP4 is required for web or cross-platform use.
Will the WMV file be bigger or smaller than my MP4?
Much smaller — the video stream is usually 80–95% of a .mp4 file's weight, and it is discarded entirely. The remaining audio is re-encoded at the bitrate implied by your quality setting.
What happens to the metadata in my MP4 file?
This converter strips container metadata deliberately (the FFmpeg command runs with metadata mapping disabled) so exported files do not leak recording details. In the source, iTunes-style metadata atoms (title, artist, cover art) plus XMP and per-track language tags; ID3 is not native to the container; none of it is transmitted anywhere because the file never leaves your browser.
Can I convert WMV back to MP4?
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .mp4 → .wmv → .mp4 is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.