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Audio Converter and Audio Extractor

Extract the audio track from a local video or convert an audio file for your next rehearsal. Inspect the actual codec, choose one track, and prepare WAV, MP3 or browser-supported AAC/M4A entirely on your device.

Updated

Input
Local audio or video file
Output
WAV, MP3 or native AAC/M4A
Privacy
No upload, converted on device
Price
Free, no account

Audio converter and extractor

Your files stay local

Interactive tool controls

Choose a file

Pick a local audio or video file. It is read on this device, never uploaded.

WAV, MP3, M4A, AAC, MP4, MOV, WebM or MKV, up to 256 MiB.

Choose the output

Pick one audio track, then the format and quality to convert to.

Inspect a file first. Its audio tracks, output formats and quality settings appear here.

Choose a local file, then inspect its audio tracks.

Limits: 256-MiB local input, 30 minutes of audio, 128-MiB output and one job at a time. Large WAV files reach the output cap sooner. Processing and downloads use page memory; leaving this page discards them. AAC encoding, decoding and the MP3 WebAssembly fallback depend on the browser. No upload, transcription or server conversion is used.

Convert the track you actually need

Inspect the file first, then convert only the track you need.

  1. Choose a local WAV, MP3, M4A, MP4, MOV, WebM, MKV or AAC file and inspect its audio tracks.
  2. Select a track and output settings. Choose PCM16 WAV for an uncompressed file or MP3 for a smaller compressed file. AAC/M4A requires a working native encoder.
  3. Convert, wait for finalization, then play the result and download it. Video is discarded without decoding and descriptive source tags are omitted.

Converting to a higher bitrate cannot recover detail lost in a compressed source. Keep the original media, especially before mixing stereo down to mono.

Browser support and local limits

Codecs depend on your browser, and every job runs in page memory.

The converter uses Mediabunny's local media pipeline, the browser's available codecs and, when needed, a WebAssembly build of the LAME MP3 encoder. Codec support varies by operating system and browser. No AI processing or paid API is involved.

A 30-minute source may be too large for uncompressed WAV: 48-kHz stereo PCM16 reaches the 128-MiB output cap at about 11.6 minutes. Use a smaller source or mono output. Cancellation releases the local worker; prior completed output stays available until you delete it or leave.

Third-party notices, licenses, corresponding source and rebuild instructions are available for the conversion libraries.

Questions about this tool

Short answers about what the tool does, what it leaves out and where your data goes.

Can every MP4, MOV, WebM or MKV be converted?

No. Containers can hold different codecs. This tool inspects local tracks and checks the available decoder and encoder. Unsupported, encrypted or damaged media is rejected; there is no hidden server fallback.

Is renaming a recording to MP3 enough?

No. An MP3 file needs MP3-encoded audio. This tool re-encodes supported audio and uses an MP3 filename only after finalization. Your browser's original recorder download keeps its actual native format.

What is the small-file WAV fallback?

If the media worker cannot decode a single audio track, you can explicitly try the browser's native audio decoder for a file up to 64 MiB and five minutes. It may still reject the codec. Decoded PCM is limited to 128 MiB. This does not make every video format supported.

Related tools and guides

Pick up where this tool leaves off.

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