Convert WTV to M4A — Free Online Tool
Convert WTV recorded TV files from Windows Media Center into M4A audio, extracting the AAC audio track into an iTunes-compatible MPEG-4 container. This is ideal for pulling audio content — talk shows, news broadcasts, or radio programs — from DVR recordings into a portable, universally playable format.
to
FFmpeg Command
Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg
Drop your WTV file here
or click to browse
Free — no uploads, no signups. Your files never leave your browser.
Settings
Note: Browser-based encoding uses approximate quality targets. For precise CRF compression, copy the FFmpeg command above and run it on your desktop.
Estimated output:
Conversion Complete!
DownloadHow It Works
WTV files are Windows Media Center DVR recordings that typically contain an H.264 or MJPEG video stream alongside an AAC or MP3 audio track. During this conversion, the video stream is completely discarded using the -vn flag, and the audio is transcoded (or in many cases, re-encoded) into AAC at 128k bitrate and wrapped in an MPEG-4 audio container (.m4a). Because WTV's audio is often already AAC, the main transformation is stripping the video, demuxing the audio, and repackaging it into the M4A format that Apple devices, iTunes, and most modern media players recognize natively. The result is a compact audio file containing only the audio content from your TV recording.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg tool, which handles all demuxing, decoding, encoding, and muxing for this WTV-to-M4A conversion. In the browser-based version of this tool, FFmpeg runs as a WebAssembly module with no server upload required. |
-i input.wtv
|
Specifies the input Windows Television (WTV) file from your Windows Media Center DVR. FFmpeg reads both the audio and video streams from this container, though only the audio will be used in the output. |
-c:a aac
|
Sets the audio codec to AAC (Advanced Audio Coding) using FFmpeg's built-in native encoder. AAC is the required codec for M4A files and is the standard audio format for Apple devices and iTunes, making it the right choice for this output format. |
-b:a 128k
|
Sets the audio bitrate to 128 kilobits per second for the AAC output. This is a solid default for broadcast TV audio content like speech and standard music; increase to 192k or 256k if you notice quality loss on music-heavy recordings. |
-vn
|
Disables video output entirely, which is mandatory here because M4A is an audio-only container and cannot hold a video stream. This flag strips the H.264 or MJPEG video track from the WTV recording, keeping only the audio. |
output.m4a
|
Defines the output file as an M4A (MPEG-4 Audio) file. The .m4a extension signals to FFmpeg to wrap the AAC audio in an MPEG-4 container, producing a file natively recognized by iTunes, Apple Music, and virtually all modern audio players. |
Common Use Cases
- Extracting the audio from a recorded news broadcast or talk show to listen to later on a smartphone or iPod without carrying a large video file
- Archiving recorded radio programs that were captured via Windows Media Center's TV tuner, converting them into M4A files for long-term audio-only storage
- Pulling the audio from a recorded lecture or educational TV program captured on a Windows Vista/7 Media Center PC to import into iTunes or an audiobook library
- Reducing the storage footprint of WTV DVR recordings when only the audio content is needed, since M4A files are a fraction of the size of the original video recording
- Preparing audio from a recorded TV interview or podcast-style show for playback on an Apple device that natively supports M4A but does not support WTV
- Batch-archiving old Windows Media Center recordings from a retired PC by stripping video and saving just the audio content in a durable, widely-supported format
Frequently Asked Questions
If the WTV file's audio track is already AAC (which is common in Windows Media Center recordings from digital broadcasts), the conversion still re-encodes the audio at 128k bitrate rather than performing a lossless stream copy, which introduces a small quality reduction. If the original WTV audio was recorded at a higher bitrate than 128k, you may notice a slight difference; bumping the -b:a value to 192k or 256k in the FFmpeg command will better preserve the original quality. If the source audio was MP3 or another codec, transcoding to AAC at 128k is generally a clean, transparent conversion for typical broadcast audio content.
WTV files store rich broadcast metadata — program title, episode name, channel, air time, and more — in a format specific to Windows Media Center. The M4A container supports iTunes-style metadata tags (title, artist, album, etc.), but FFmpeg does not automatically map WTV's broadcast metadata fields to M4A tags during this conversion. You would need to manually tag the resulting M4A file using a tool like MP3Tag or iTunes after conversion if you want the metadata preserved.
WTV files can contain multiple audio tracks — for example, a secondary language track or a Descriptive Video Service (DVS) track. By default, FFmpeg selects the first (default) audio track for the output M4A. M4A does not support multiple audio tracks in a single file, so only one track will be included. If you need a non-default track, you can specify it by adding -map 0:a:1 (for the second audio track) to the FFmpeg command before the output filename.
M4A is an MPEG-4 container specifically designed for audio-only content, making it the ideal wrapper for AAC-encoded audio. Unlike a raw .aac file, M4A supports chapter markers, iTunes metadata, and gapless playback, which makes it more versatile for long-form content like broadcast recordings. MP3 is an alternative, but AAC in M4A generally achieves better audio quality at the same bitrate, which is especially noticeable at 128k for voice and music content typical in TV recordings.
Replace the 128k value in the -b:a 128k flag with a higher bitrate. For example, use -b:a 192k for noticeably better quality or -b:a 256k for near-transparent AAC audio. The full modified command would look like: ffmpeg -i input.wtv -c:a aac -b:a 192k -vn output.m4a. For typical broadcast TV speech content, 128k is usually sufficient, but for music or high-quality broadcasts, 192k or higher is recommended.
Yes. On Windows, you can use a simple batch script: for %f in (*.wtv) do ffmpeg -i "%f" -c:a aac -b:a 128k -vn "%~nf.m4a". On macOS or Linux, the equivalent shell command is: for f in *.wtv; do ffmpeg -i "$f" -c:a aac -b:a 128k -vn "${f%.wtv}.m4a"; done. This is particularly useful when archiving an entire library of Windows Media Center recordings, and is the recommended approach for collections exceeding the 1GB browser-based tool limit.
Technical Notes
WTV is a container format specific to Windows Vista and Windows 7 Media Center, and its internal structure includes not just audio and video but also DVR metadata, EPG (Electronic Program Guide) data, and potentially subtitle streams. FFmpeg has solid WTV demuxing support, but some recordings — particularly those from encrypted cable or satellite tuners — may fail to decode due to DRM protection. The -vn flag is essential here because M4A is an audio-only container and will reject a video stream. The AAC encoder used (-c:a aac) is FFmpeg's built-in native AAC encoder, which produces good quality at 128k and above; for archival use, consider libfdk_aac if available in your FFmpeg build, as it is generally considered higher quality. M4A supports chapter markers, which could theoretically be useful for long TV recordings, but WTV chapter data is not automatically mapped during this conversion. Subtitle tracks present in the WTV file are also silently dropped, as M4A has no subtitle support. File sizes will be dramatically smaller than the original WTV — a one-hour standard-definition recording might shrink from several gigabytes down to roughly 50–100MB as an M4A at 128k.