Convert Video to MP3 Free Online
Extract the audio track from MP4, MOV, WebM, or MKV video as an MP3 for free in your browser. No upload. Your files stay on your device.
Convert video to MP3 when the audio is the part you actually need: a lecture, interview, meeting recording, podcast draft, voice note, screen recording, webinar, or performance where you only want to listen.
Keeping the full video is often unnecessary if you are going to transcribe it, listen while commuting, save space, or send the sound to someone for review. An MP3 is usually smaller, easier to organize, and more convenient in audio apps than a video file.
Do not convert to MP3 just to preserve the best possible quality. MP3 is a lossy audio format, so it is best for convenient listening and sharing. Keep the original video or source audio if you may need the highest-quality version later.
GrepCut opens your video in the browser, reads the audio track, and discards the picture. It then encodes the audio as a 192 kbps MP3, which is a practical setting for speech, interviews, lessons, podcasts, and everyday listening.
Because the tool is extracting audio rather than converting the full video, the output is usually much smaller than the original file. At 192 kbps, an MP3 is roughly 1.4 MB per minute before small container overhead, so long recordings are easier to store and send than video.
The conversion is private by design because the media processing happens locally on your device. That matters for meetings, client recordings, internal demos, personal videos, and anything you would rather not upload to a third-party converter.
Extracting MP3 does not improve bad audio. If the source has background noise, clipping, echo, low volume, or a poor microphone, the MP3 will usually keep those problems.
It also cannot create sound from a silent video. If the file has no audio track, there is nothing to extract.
Use this tool when you need a convenient audio copy. For professional editing, mixing, archiving, or maximum quality, keep the original recording and use a lossless or higher-quality workflow when available.
Is my video uploaded anywhere?
No. The conversion runs locally in your browser using WebCodecs and a WebAssembly MP3 encoder. Your media file does not need to be uploaded to GrepCut for extraction.
What bitrate is the MP3?
GrepCut exports MP3 at 192 kbps. That is a practical setting for speech, interviews, lessons, podcasts, and general listening, while keeping the file much smaller than the original video.
Will the MP3 sound exactly like the original?
No. MP3 is lossy, which means some audio detail is removed during encoding. For everyday listening this is usually acceptable, but you should keep the original file if quality matters later.
How much smaller will the MP3 be?
It depends on the video, but audio-only MP3 is usually much smaller because the video stream is removed. At 192 kbps, the MP3 is roughly 1.4 MB per minute before small overhead.
What if my video has no audio track?
Then there is nothing to extract. Choose a file that contains sound and try again.
Which video formats work?
GrepCut accepts MP4, MOV, WebM, and MKV inputs. The output is an MP3 audio file.
Can I use this for copyrighted music or videos?
Only extract audio from files you own, created, have permission to use, or are otherwise allowed to convert. The tool is for format conversion, not for bypassing rights or restrictions.
Should I trim the video first?
Yes, if you only need part of the recording. Cutting dead air, intros, repeated takes, or unused sections first gives you a shorter and cleaner MP3.