Video to MP3

How to extract audio from a video: MP3, M4A or WAV?

GGrabivo TeamUpdated November 6, 2026

A video holds a picture track and a sound track. Saved as M4A, an AAC soundtrack is copied untouched. Saved as MP3, it is encoded again. This guide shows which to pick, how big each file gets and how to do it in a browser or with ffmpeg.

To extract audio from a video without losing quality, save it as M4A. If the video's sound is AAC, as in most MP4 and MOV files, it is copied into the new file untouched. Choose MP3 when a device or app needs it; that re-encodes the sound, so use 192 kbit/s for speech and 320 kbit/s for music.

Which format keeps the original sound?

A video file holds a picture track and a sound track in one container. Extracting the audio means writing the sound track to a file of its own. When the output codec matches the source codec, the data is copied as it is and nothing is lost. When it does not match, the sound is decoded and encoded again, and every lossy encode drops a little more detail. M4A holds AAC, so an AAC soundtrack can be copied. MP3 is a different codec, so it is always re-encoded. WAV stores uncompressed samples. It adds no further loss, but it cannot bring back detail that the video's own encoder already removed.

How big is the audio file at each setting?

Size follows the bitrate: kilobits per second times the length, divided by 8. The table counts audio data only, with 1 MB as 1,000,000 bytes. An M4A copy takes the size of the source's own audio track, so a 128 kbit/s AAC track needs the same space as the 128 kbit/s MP3 row.

How do I extract the audio in a browser?

• Open the Grabivo video to MP3 converter and drop the file on the box. MP4, MOV, WEBM and MKV files work, up to five at a time and 1 GB each.
• Pick the format. M4A comes first: if the video carries AAC, the audio is copied and the job finishes in seconds. Pick MP3 when you need that format, or WAV when you will edit the sound further.
• For MP3, choose the bitrate: 128 kbit/s for a small file, 192 kbit/s as the default, 320 kbit/s for music.
• Press Extract the audio, play the result in the page and download it.

The work runs in your browser tab. The video is not uploaded and the original file stays as it was. Extract only audio you made or have permission to save.

How do I check which audio codec my video has?

• Run ffprobe -v error -select_streams a:0 -show_entries stream=codec_name -of default=nw=1:nk=1 input.mp4. It prints the codec name of the first audio track.
• If it prints aac, an M4A export is a straight copy. Other names such as mp3, opus or vorbis are decoded and encoded again, whichever format you choose.
• WEBM files usually carry Opus or Vorbis, so expect a re-encode there.

How do I extract audio with ffmpeg?

• To copy an AAC soundtrack into an M4A file, run ffmpeg -i input.mp4 -vn -c:a copy output.m4a. The -vn option leaves the video out.
• To make an MP3, run ffmpeg -i input.mp4 -vn -c:a libmp3lame -b:a 192k output.mp3. The -b:a value sets a constant bitrate; -q:a sets a variable one.
• The FFmpeg documentation lists the libmp3lame options at ffmpeg.org/ffmpeg-codecs.html.

When is MP3 the better choice?

Pick MP3 when the file has to play almost anywhere: older players, car stereos, phones, editing and podcast tools. The bitrate also lets you aim for a size. M4A with AAC plays on current phones and computers, but a few older devices and some apps accept only MP3. If you do not know where the file will end up, MP3 at 192 kbit/s is the safe default.

Does a higher bitrate make the audio sound better?

Only up to the quality of the source. A video with 128 kbit/s AAC sound does not hold more detail than that. A 320 kbit/s MP3 made from it is a bigger file with the same sound, plus a second round of lossy encoding. If you know the source bitrate, choose an MP3 setting at or above it, or copy to M4A and skip the question.