Extract Audio from WTV to MP3 — Free Online Tool
Extract audio from WTV recordings captured by Windows Media Center and convert it directly to MP3. This tool strips the video stream and re-encodes the AAC audio track from your DVR recordings into universally compatible MP3 using the LAME encoder — all processed locally in your browser with no upload required.
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 recorded by Windows Vista/7/8 Media Center typically contain an H.264 video stream and an AAC audio stream, along with broadcast metadata such as program titles and air times. This conversion discards the video stream entirely and re-encodes the AAC audio from the WTV container into MP3 using the libmp3lame encoder. Because AAC and MP3 are different codecs (not just different containers), a full audio decode-and-reencode must occur — the AAC bitstream is decoded to raw PCM audio, then compressed again as MP3 at the target bitrate. This means there is a small but measurable generation loss compared to the original broadcast audio. The resulting MP3 file is a single audio track; if your WTV recording contained multiple audio tracks (such as SAP or secondary language tracks), only the default track is extracted unless you specify otherwise.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg program, the open-source multimedia processing engine that handles demuxing the WTV container and transcoding the audio. In the browser, this runs via FFmpeg.wasm compiled to WebAssembly. |
-i input.wtv
|
Specifies the input file as a WTV (Windows Television) recording. FFmpeg automatically detects the WTV container and identifies the enclosed video and audio streams, including any broadcast metadata. |
-vn
|
Disables video output entirely, telling FFmpeg to ignore the H.264 video stream in the WTV file. Without this flag, FFmpeg would attempt to include or re-encode video, which would fail when writing to an MP3 output file that supports only audio. |
-c:a libmp3lame
|
Selects the LAME MP3 encoder to transcode the AAC audio from the WTV recording into MP3 format. Since AAC and MP3 are different codecs, a full decode-reencode is required — stream copying is not possible here. |
-b:a 128k
|
Sets the MP3 output to a constant bitrate of 128 kilobits per second, which is the standard default for general-purpose MP3 encoding. This provides a reasonable balance between file size and audio quality for typical TV broadcast audio content. |
output.mp3
|
Defines the output filename and tells FFmpeg to write the result as an MP3 file. The .mp3 extension also confirms to FFmpeg that it should use the MP3 muxer, producing a file compatible with virtually all audio players, devices, and streaming services. |
Common Use Cases
- Extract the audio commentary or narration from a recorded TV documentary to listen to it offline without carrying the large WTV video file
- Pull the audio from a recorded live musical performance or concert broadcast so you can add it to your music library as an MP3
- Archive the audio portion of a recorded news broadcast or interview for research or transcription purposes, discarding the bulky video
- Convert old Windows Media Center DVR recordings to MP3 so the audio is playable on devices that cannot handle the WTV container, such as older portable MP3 players
- Extract recorded radio shows or talk programs that were captured via a TV tuner card in WTV format and convert them into a podcast-friendly MP3 for playback in any podcast app
- Recover usable audio from a partially corrupted WTV recording where the video track is damaged but the audio stream is still intact
Frequently Asked Questions
Yes, there is a small but real quality loss. WTV files from Windows Media Center store audio as AAC, which is already a lossy compressed format. Converting to MP3 requires decoding the AAC back to uncompressed PCM and then re-encoding it as MP3 — a process called transcoding. This introduces a second generation of lossy compression artifacts. At the default 128k bitrate the result is generally acceptable for speech and most music, but audiophiles may want to use 192k or 320k to minimize the difference.
By default, FFmpeg selects the first (primary) audio stream, which is typically the main language track chosen by your tuner card during recording. If you need a specific secondary track, you would need to modify the FFmpeg command to add a flag like '-map 0:a:1' to select the second audio stream by index. The browser tool extracts the default track automatically, so use the displayed FFmpeg command locally if you need to target a specific track from a multi-track WTV file.
WTV files embed rich DVR metadata such as program names, channel information, air times, and descriptions. When converting to MP3, FFmpeg may carry over some basic metadata fields as ID3 tags, but WTV-specific broadcast fields that have no MP3 ID3 equivalent will be dropped. You should not expect the episode title or channel name to automatically appear in your MP3 player — you may need to manually edit the ID3 tags after conversion using a tag editor if that metadata matters to you.
Replace the '-b:a 128k' value in the command with your desired bitrate. For smaller files suitable for speech recordings, '96k' works well. For high-quality music extraction where fidelity matters, use '256k' or '320k', which is the maximum standard MP3 bitrate. For example: 'ffmpeg -i input.wtv -vn -c:a libmp3lame -b:a 256k output.mp3'. The file size scales roughly linearly with bitrate, so 256k produces approximately twice the file size of 128k.
The browser tool processes one file at a time, but you can adapt the displayed FFmpeg command for batch processing on your desktop. On Windows, a simple batch script would loop over all WTV files in a folder: 'for %f in (*.wtv) do ffmpeg -i "%f" -vn -c:a libmp3lame -b:a 128k "%~nf.mp3"'. On Linux or macOS, use: 'for f in *.wtv; do ffmpeg -i "$f" -vn -c:a libmp3lame -b:a 128k "${f%.wtv}.mp3"; done'. This is especially useful for processing large WTV archives from an old Windows Media Center PC.
WTV files contain a full H.264 video stream in addition to the audio, and video data accounts for the overwhelming majority of a recording's file size — often 90–95% or more. By stripping the video with '-vn', only the audio track survives, which is a small fraction of the original. A one-hour WTV recording might be 4–8 GB, while the extracted 128k MP3 audio for the same duration would typically be around 55–65 MB. This dramatic size reduction is expected and correct.
Technical Notes
WTV is a container format exclusive to Windows Media Center (Vista through Windows 8.1), and it wraps MPEG-2 Transport Stream data with a proprietary Microsoft wrapper that includes DVR-specific metadata. FFmpeg has solid WTV demuxing support, but because WTV was designed for a Microsoft ecosystem, edge cases can arise — particularly with recordings from certain tuner cards that used non-standard bitrates or stream configurations. The audio in WTV is most commonly AAC-LC at 128k–192k, though some recordings may contain MP3 audio already (libmp3lame), in which case a copy pass would theoretically be possible but FFmpeg will still transcode by default in this workflow. The '-vn' flag is essential to prevent FFmpeg from attempting to encode the H.264 video stream into MP3 (which would fail). MP3 output using libmp3lame with '-b:a' specifies a constant bitrate (CBR); if you prefer variable bitrate encoding for better quality-to-size efficiency, you can substitute '-q:a 2' (VBR mode, roughly equivalent to 190k average) instead of '-b:a 128k'. Note that MP3 does not support chapter markers, so any chapter-like segment data from the WTV recording is lost, and MP3's ID3 tag support for extended broadcast metadata is limited compared to WTV's native DVR fields.