Add your WMV file
Drop one or more .wmv 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.
WMV to M4V
Pulling the soundtrack out of a .wmv video into .m4v 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 WMV 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 Windows Media video to MPEG-4 video
Pulling the soundtrack out of a .wmv video into .m4v audio keeps what you can hear and drops the picture entirely. 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.
An .m4v file is Apple's flavor of the MPEG-4 container, used by iTunes for movies, TV episodes, and music videos. Structurally it is almost identical to .mp4, but the .m4v extension signaled iTunes-specific features such as chapter markers and, on purchased content, FairPlay copy protection. For this route the practical draw is a DRM-free .m4v is a plain MP4, so a rename alone often fixes compatibility and carries chapters and artwork more gracefully than most containers — balanced against fairPlay-protected files play only in Apple apps on authorized devices, and no converter can open them, which is worth knowing before you commit a large batch.
Why convert WMV to M4V?
The usual reason to take .m4v audio out of a .wmv 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, effectively abandoned by Microsoft itself; on the target side, the payoff is a DRM-free .m4v is a plain MP4, so a rename alone often fixes compatibility, which is exactly what you want for playing back iTunes-era video libraries.
WMV vs M4V at a glance
| Aspect | Windows Media video (.wmv) | MPEG-4 video (.m4v) |
|---|---|---|
| Format type | Container — quality depends on the codecs and settings inside | Container — quality depends on the codecs and settings inside |
| How it stores data | aSF container carrying WMV1, WMV2, or WMV3 (VC-1) video, typically with WMA audio | identical ISO base media layout to MP4, distinguished only by branding atoms and the extension |
| Strongest at | playing old Movie Maker projects and family archives | playing back iTunes-era video libraries |
| Weak spot | effectively abandoned by Microsoft itself | fairPlay-protected files play only in Apple apps on authorized devices, and no converter can open them |
| Metadata | aSF content-description attributes hold title, author, copyright, and rating fields, plus extended attributes used by Windows Media Player libraries | full iTunes atom metadata: title, show, season, episode, artwork, chapters, and content ratings |
Pick M4V as the output
Select .m4v in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if M4V 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 M4V file. Outputs keep the original filename with the .m4v extension.
WMV to M4V questions, answered
Will converting WMV to M4V lose quality?
Since wmv is container-oriented and m4v is container-oriented, the conversion preserves the source content exactly as stored; no additional compression pass is applied beyond what .m4v itself requires.
Is it private to convert WMV files here?
Yes — the .wmv 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 M4V file work?
Apple devices treat .m4v as native, and most other players accept the file after inspecting its contents or following a rename to .mp4. The exception is DRM-protected iTunes video, which remains locked to Apple's own apps.
Will the M4V file be bigger or smaller than my WMV?
Much smaller — the video stream is usually 80–95% of a .wmv 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 WMV 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, aSF content-description attributes hold title, author, copyright, and rating fields, plus extended attributes used by Windows Media Player libraries; none of it is transmitted anywhere because the file never leaves your browser.
Can I convert M4V back to WMV?
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .wmv → .m4v → .wmv is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.