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.
Pulling the soundtrack out of a .mp4 video into .wma audio keeps what you can hear and drops the picture entirely. Free, private, and validated — the file never leaves your browser.
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.Pulling the soundtrack out of a .mp4 video into .wma 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 .wma file contains Windows Media Audio, Microsoft's proprietary compressed format, wrapped in the same ASF container as WMV video. It shipped with every copy of Windows for a decade, so ripped CDs and store purchases from that era survive as .wma libraries. For this route the practical draw is respectable quality at mid bitrates for its era and still opens on any Windows PC without extra software — balanced against proprietary and effectively abandoned, which is worth knowing before you commit a large batch.
The usual reason to take .wma 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 respectable quality at mid bitrates for its era, which is exactly what you want for converting old ripped-CD libraries to MP3 or FLAC.
| Aspect | MP4 video (.mp4) | Windows Media audio (.wma) |
|---|---|---|
| Format type | Container — quality depends on the codecs and settings inside | Lossy — discards detail it judges invisible to shrink files |
| 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 | the standard codec is a lossy transform coder supporting up to 48 kHz stereo |
| Strongest at | publishing video to the web, social media, or a client who has not specified a format | converting old ripped-CD libraries to MP3 or FLAC |
| Weak spot | fewer track, attachment, and chapter features than Matroska | proprietary and effectively abandoned |
| Metadata | iTunes-style metadata atoms (title, artist, cover art) plus XMP and per-track language tags; ID3 is not native to the container | aSF attributes mirror ID3 basics such as title, artist, album, and artwork, and Windows Media Player wrote extended library fields on top |
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.
Select .wma in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if WMA is selectable, the route is real and validated.
Press Convert. A WebAssembly FFmpeg build demuxes the audio track and re-encodes it locally; the video stream is simply discarded.
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid WMA file. Outputs keep the original filename with the .wma extension.
Since mp4 is container-oriented and wma is lossy-oriented, the conversion preserves the source content exactly as stored; no additional compression pass is applied beyond what .wma itself requires.
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.
Windows continues to play .wma through its bundled apps, but macOS, iOS, Android, and all web browsers lack native support. Files protected by Windows Media DRM will not play anywhere now that their license servers are gone.
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.
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.