How to convert MP4 video to MP3 online
Extracting audio from a video takes four quick steps with VideoToMP3 — no software to install and no account required.
01 Add your video
Drag and drop an MP4, WEBM, MOV or AVI file onto the upload zone, or click it to browse your device.
02 Choose quality
Pick 128, 192 or 320 kbps and select stereo or mono. Optionally normalize the volume or add soft fades.
03 Trim the audio
Drag the start and end handles under the waveform or type exact times, then preview your selection.
04 Convert & download
Click Convert & Download MP3. The file is encoded in your browser and saved automatically.
Why extract audio from video in your browser?
Private by design
Traditional online converters upload your video to a remote server. VideoToMP3 decodes and encodes everything on your own device using the Web Audio API.
No waiting in queues
Without uploads or downloads to a server, conversion speed depends only on your device — most videos finish in seconds.
Free, no limits
No watermarks, no sign-up, no daily caps. Convert as many videos to MP3 as you like.
What is the best audio bitrate for MP3 conversion?
Bitrate controls how much data is used per second of audio. Higher bitrates sound closer to the original but produce bigger files.
| Bitrate | Quality | Best for | Size / min |
|---|---|---|---|
| 128 kbps | Standard | Podcasts, lectures, voice notes, audiobooks | ≈ 0.96 MB |
| 192 kbps | High | Music, music videos, everyday listening | ≈ 1.44 MB |
| 320 kbps | Maximum | High-quality sources, DJ sets, archiving | ≈ 2.40 MB |
Tip: converting can't add quality that wasn't in the source. If a video's audio track is 128 kbps AAC, exporting at 320 kbps only makes the file larger.
Supported video formats
- MP4 to MP3 & M4V to MP3
- The most common video format from phones, cameras and screen recorders. Usually AAC audio, decoded natively.
- WEBM to MP3
- Web video with Opus or Vorbis audio — supported natively in Chrome, Edge, Firefox and modern Safari.
- MOV to MP3
- QuickTime files from iPhone and Mac. Most MOV files with AAC audio decode instantly.
- AVI, MKV & others to MP3
- When a browser can't decode a container natively, VideoToMP3 loads an in-browser FFmpeg engine on demand (one-time ~30 MB download, still fully local).
Frequently asked questions
How to convert MP4 video to MP3 online?
Open VideoToMP3, drop your MP4 file onto the upload zone, pick a bitrate (128, 192 or 320 kbps), optionally trim the start and end, then click Convert & Download MP3. The audio is extracted and encoded to MP3 directly in your browser and downloads automatically.
Are my uploaded videos secure and private?
Yes. VideoToMP3 never uploads your files. Decoding and MP3 encoding happen 100% inside your browser using the Web Audio API and a JavaScript MP3 encoder, so your video never leaves your device. You can even disconnect from the internet after the page loads and it keeps working for common formats.
What is the best audio bitrate for MP3 conversion?
192 kbps is the best all-round choice for music and is near-transparent for most listeners. 320 kbps is the maximum MP3 quality and suits high-quality source audio. 128 kbps is fine for speech, podcasts and lectures and produces the smallest files.
Which video formats can I convert to MP3?
MP4, WEBM, MOV and AVI, plus M4V, MKV and most audio files. Common formats decode natively in the browser; less common containers such as AVI are handled by an optional in-browser FFmpeg engine that loads only when needed.
Can I extract only part of the audio from a video?
Yes. After loading a video, drag the start and end handles on the waveform or type exact start and end times. You can preview the selected region before converting, and only that portion is saved as MP3.
Is there a file size limit?
There is no server-side limit because nothing is uploaded. The practical limit depends on your device memory; most computers handle videos of several hundred megabytes or more than an hour of audio without issues.
Does VideoToMP3 work on iPhone and Android?
Yes. VideoToMP3 works in modern mobile browsers such as Safari on iOS and Chrome on Android. Very long videos may be slower on phones because all processing runs on the device.