Free converter · Extract audio

Convert M4V to MP3

Runs in your browserNo uploadUp to 100 MB

Short answer

Drop your M4V file into the converter below and download the MP3 file. It runs in your browser with FFmpeg, for files up to 100 MB; nothing is uploaded. Only the sound is kept: the video track is dropped and the audio is saved as MP3 audio at about 128 kbps, keeping the source's sample rate.

Maximum file size: 100 MB. The first conversion loads a ~30 MB converter engine, once per visit. Nothing is uploaded - conversion runs on your device.

Extract audio from M4V into MP3. · Extract audio · Browser-side via FFmpeg WASM - nothing uploaded.

Key takeaways

  • The 8.88 MB M4V file became a 161 KB MP3 file (-98.2%), about 128 kbps for the 10 second clip.
  • The result holds: Audio: mp3 48000 Hz 2 ch.
  • In your browser the same conversion of a 3 second clip took 0.19 seconds on the single-thread engine; natively, the 10 second clip took 0.24 seconds.
  • Next to it: M4V to AAC (-98.2%), M4V to AVI (-70.6%), M4V to GIF (+592%).

Measured: M4V to MP3

The converter's own ffmpeg arguments, run on a 10 second 1920 × 1080 excerpt of Big Buck Bunny (an animated film, not camera footage) saved in M4V. The browser column is the same arguments on the single-thread WebAssembly core with a 3 second excerpt, in a headless run; your device will differ. Results describe this clip and these encoders.

CheckResult
ModeAudio re-encoded
InputM4V, 8.88 MB
OutputMP3, 161 KB (-98.2%)
Output streamsAudio: mp3 48000 Hz 2 ch
Time, native, 10 s clip0.24 s
Time, browser engine, 3 s clip0.19 s

A re-encode decodes and encodes every frame or sample, so the time grows with the length of the file.

M4V vs MP3

M4VMP3
Full nameApple MPEG-4 videoMPEG-1 Audio Layer III
What is insideH.264 video with AAC audio, the same structure as MP4MP3 audio
CompressionDepends on the codec insideLossy
Best forApple TV and iTunes; files bought from iTunes may be copy-protected and cannot be convertedMusic and podcasts that must play on every device

What you get

MP3 audio at about 128 kbps, keeping the source's sample rate. Extract audio from M4V into MP3.

Planning a bigger file

These are estimates scaled up from the 10 second clip. Real files differ with content, resolution and bitrate, so treat them as an order of magnitude, not a promise.

Length of the video or recordingInput size (like ours)MP3 sizeTime in your browser
1 minute53.12 MB962 KB4 seconds
10 minutes531.21 MB9.62 MB38 seconds
1 hour3187.23 MB57.74 MB3.8 minutes

An M4V file of this kind reaches the 100 MB limit of the converter after about 2.0 minutes; converting it would take roughly 8 seconds on the single-thread engine, and the MP3 would be about 1.90 MB.

M4V and MP3 next to their neighbors

The same clip through other conversions with the same source or the same target.

ConversionHowSize changeTime (native)
M4V to MP3Re-encode-98.2%0.24 s
M4V to AACRe-encode-98.2%0.30 s
M4V to AVIRe-encode-70.6%1.5 s
M4V to GIFRe-encode+592%5.5 s
M4V to M4ARe-encode-98.2%0.30 s
M4V to MKVCopy-0.1%0.11 s
M4V to MOVCopy0.0%0.09 s

Choosing MP3

MP3: MPEG-1 Audio Layer III. Music and podcasts that must play on every device. M4V: Apple MPEG-4 video. Apple TV and iTunes; files bought from iTunes may be copy-protected and cannot be converted.

  • Keep your original: a re-encode is a copy of a copy.
  • If the destination states the format it accepts, use that and nothing else.

Questions people ask

Is this M4V to MP3 converter free and private?

Yes. It is free, needs no account and runs entirely in your browser, so the file never leaves your device.

Will converting M4V to MP3 reduce quality?

The audio is re-encoded to MP3, a lossy format, so there is a small loss compared with the original track.

Is there a file size limit?

Files up to 100 MB. The first conversion downloads a converter engine of about 30 MB once per visit; larger files are better handled by a desktop app such as HandBrake or FFmpeg.

How do I convert M4V to MP3?

Choose the file in the converter above and download the MP3. It runs in your browser with no upload.

Will converting M4V to MP3 reduce quality?

A little, because MP3 is lossy. Keep the original file.

Why did the file size change by -98.2%?

The target codec and settings decide the size. This 10 second clip came out at 161 KB, about 128 kbps.

How long does it take?

A 3 second clip took 0.19 seconds in the browser engine in our test; time grows with the length of the file.

How long will an M4V file of 100 MB take?

At the speed we measured in the browser engine, about 8 seconds for a file like our clip. Your device and the content will change it.

Is my file uploaded?

No. The conversion runs in your browser.

Is there a size limit?

Files up to 100 MB. The first conversion downloads a converter engine of about 30 MB once per visit.

More converters

Sources and how we checked

  1. MDN: Media container formats
  2. MDN: Web audio codec guide
  3. MDN: Image file type and format guide
  4. FFmpeg documentation: stream copy
  5. FFmpeg Documentation: ffmpeg (stream selection, -map, -c copy) (read 2026-10-09)
  6. MDN: Web audio codec guide (read 2026-10-09)
  7. Blender Foundation: Big Buck Bunny (CC BY 3.0), the clip used for the measurements (read 2026-10-09)

Reviewed October 8, 2026. What the converter writes was measured with ffprobe on the same FFmpeg build your browser downloads; format descriptions follow MDN's media guides.