What happens when you convert M4A to WMV
- WMV is a video format. The audio is encoded as WMA audio, and by default the file has no picture.
- Tick "Add a black video track" if the WMV is going to YouTube or another site that rejects audio-only video.
How to convert M4A to WMV online
- Press "Choose M4A files" and select one or more files, or drag them onto the box. You can add files of any size your device can hold in memory.
- Adjust the settings if you need to: resolution and quality control the size of the result. The defaults suit most people.
- Press "Convert to WMV". The first audio or video conversion downloads the converter engine, about 32 MB, which your browser then keeps for next time.
- Save each WMV with its download button. Close the tab and every trace of the files is gone from memory.
Why convert M4A to WMV?
M4A files usually come from iTunes purchases, iPhone voice memos and Apple Music downloads. People convert them to WMV because WMV plays in Windows Media Player and in older PowerPoint versions without extra codecs.
In short, M4A is good at what it was made for, and WMV is the more practical choice when the file has to play, upload or edit somewhere else. M4A plays in all current browsers and every Apple device, while WMV does not play in browsers; plays in Windows Media Player and Films and TV.
How to convert M4A to WMV on Windows, Mac, iPhone and Android
On Windows
Open this page in Chrome, Edge or Firefox, drag your M4A files in from File Explorer, and press Convert. Each WMV is saved to your Downloads folder. If you prefer a desktop program, VLC can also convert M4A to WMV: choose Media, then Convert / Save.
On a Mac
Safari, Chrome and Firefox all work. Drag the M4A files from Finder onto the drop zone and the WMV files land in Downloads.
On iPhone and iPad
Open the page in Safari and tap Choose M4A files. You can pick from Photos or from the Files app. The converted WMV appears in Files, in the Downloads folder; to put it in your photo library, open it there, tap Share and choose Save Video.
On Android
Open the page in Chrome, tap Choose M4A files and pick them from Files or your gallery. The WMV is saved to the Download folder, where any file manager can find it. Keep the screen on while a long video converts, because Android may pause a tab in the background.
Best settings for M4A to WMV
WMV is written as Windows Media Video 8 with WMA audio. The Resolution setting is the one to reach for: 1080p keeps full HD detail, 720p is plenty for phones and laptops and roughly halves the size, and 480p suits email and old devices.
The quality levels map to the H.264 CRF scale where the target uses H.264, and to fixed high-quality settings for older codecs such as MPEG-2, MPEG-4 Part 2, WMV and Theora. Re-encoding always costs a little detail, so convert from the best copy of the M4A you have.
M4A vs WMV: the differences
| M4A | WMV | |
|---|---|---|
| Full name | MPEG-4 Audio | Windows Media Video |
| Type | audio | video |
| Created by | Apple, on the MPEG-4 standard | Microsoft |
| First released | 2001 | 1999 |
| Compression | Lossy or lossless | Lossy |
| Usually contains | AAC, or ALAC for lossless files | WMV video with WMA audio in an ASF container |
| In a browser | plays in all current browsers and every Apple device | does not play in browsers; plays in Windows Media Player and Films and TV |
| Common uses | iTunes purchases, iPhone voice memos and Apple Music downloads | Windows Movie Maker exports and older corporate video |
| MIME type | audio/mp4 | video/x-ms-wmv |
About M4A and WMV files
What is an M4A file?
M4A is an MP4 file that only holds audio, which is why renaming one to .mp4 often works. Voice Memos on iPhone saves recordings as M4A.
What is a WMV file?
WMV was the default export of Windows Movie Maker, so many home videos from the 2000s are in it. Macs and iPhones never played it natively.
M4A to WMV not working? Common problems
- The conversion is slow. Audio and container changes take seconds, but re-encoding video runs on your own processor. Lower the resolution to 720p, close other tabs, and keep the device plugged in.
- The tab stops or reloads on a very large file. Browsers limit how much memory one tab can use, around 2 GB and less on phones. Split long recordings or convert them on a computer.
- The WMV will not play on an old device. Try the other formats offered for M4A, or choose 720p, which older players handle more reliably.
Convert M4A to WMV with ffmpeg
This converter runs ffmpeg inside your browser. If you would rather use the ffmpeg command line on your own computer, this command produces an equivalent WMV with the same kind of settings:
ffmpeg -i input.m4a -c:v wmv2 -b:v 2500k -c:a wmav2 -b:a 192k output.wmvReplace input.m4a with the name of your file. For a whole folder of M4A files, run the command in a loop, or drop them all on the converter above, which processes them one after another.
M4A to WMV converter FAQ
Will I lose quality converting M4A to WMV?
A little. Both formats are lossy, so re-encoding compounds the loss slightly. Keep the default quality or higher and the difference is rarely noticeable.
Why is the WMV a different size from the M4A?
Without a picture, the WMV is about the size of the audio. Adding a black video track adds a little, because a still black frame compresses to almost nothing.
Are my M4A files uploaded anywhere?
No. The conversion runs inside this browser tab using ffmpeg compiled to WebAssembly, so your files stay on your device. You can disconnect from the internet after the page and converter engine have loaded and it still works.
Can I convert several M4A files to WMV at once?
Yes. Select or drop as many files as you like; they are converted one after another and each gets its own download button.
How do I open a WMV file?
WMV does not play in browsers; plays in Windows Media Player and Films and TV. WMV is common for Windows Movie Maker exports and older corporate video.
Is this M4A to WMV converter free?
Yes. There is no sign-up, no watermark and no limit on how many files you convert. The site is paid for by advertising, and because conversions run on your device there is no server cost per file.
Can I convert M4A to WMV on my phone?
Yes. The converter works in Safari on iPhone and iPad and in Chrome on Android. Long HD videos convert more slowly on a phone than on a computer.