Convert MP4 to MP3
If you only need the sound of a talk, lesson or concert you filmed on your phone, convert the MP4 to MP3. Dropping the video track makes the file much smaller, and the audio plays on any device.
Free · no sign-up · your file is processed in your browser and never sent to a server
How to use
- Choose your MP4 fileDrop one or more MP4 files. On this page the tool only accepts MP4; for other formats, use the audio converter.
- Pick the qualityChoose the MP3 bitrate: 128 kbps for speech, 192–320 kbps for music.
- Convert and downloadFiles are processed one after another; each finished file comes with its own download link.
MP4 and MP3 at a glance
| MP4 | MP3 | |
|---|---|---|
| Codec | Video + audio; audio usually AAC | MPEG Layer III |
| Type | Video container | Lossy |
| Approx. size | Most of the size is video; the audio track is a small part | 128 kbps: ~1 MB/min · 320 kbps: ~2.4 MB/min |
| Typical source | Phone cameras, screen recordings, video editor exports | Music libraries, podcasts, recorder apps, almost every device |
Why convert?
- Listening to a video's audio on a music player or phone
- Sharing a lecture or meeting recording as a small file
- Preparing just the audio before transcribing the speech
Common issues with MP4 files
- Silent video: Some screen recordings have no audio track; the tool will tell you.
- Multiple audio tracks: Some MP4s carry more than one language track; the tool takes the primary one.
- Very large videos: The file is read without loading it into memory all at once (up to 2 GB); long videos can still take a few minutes.
Privacy: your file never leaves your device
Everything happens in your browser. Your file is not sent to Voiser's servers or stored anywhere, and it's cleared from memory when you close the tab. That's also why the tool stays fast on a slow connection.
Other conversions
Common questions
Does converting MP4 to MP3 damage the video?
No. Your original video file isn't changed; the tool writes a copy of the audio track as MP3.
Can I get the audio without any quality loss?
Yes: choose M4A as the output. If the video's audio is AAC, it's copied without re-encoding.
Can I convert a YouTube video to MP3?
No. The tool only works with files on your device and doesn't download from sites. Only process videos you own or have permission to use.
Does it work with MOV or WEBM?
Yes. For every video format, use extract audio from video; this page is set up for MP4 files.
Related tools
- Audio converterConvert files between MP3, WAV, M4A, OGG and FLAC.
- Extract audio from videoSave the audio track of your own videos as MP3, M4A or WAV.
- MP3 cutter and audio trimmerSelect any part of an audio file on the waveform and cut it out.
- Audio joinerMerge several audio files into one, in the order you choose.
Turn your converted recording into text.
Transcription turns speech into time-stamped text with separate speakers. Start with a free account.