MP4 to MP3 Converter
Drop in an MP4 video, pick a bitrate and download the audio as an MP3 in seconds.
Audio Settings
Quick answer: how to convert MP4 to MP3
To convert MP4 to MP3 online, drop your video into the box above, choose a bitrate (192 kbps is a good default) and click Convert & Download. The tool pulls out the audio track and saves it as an MP3 file. It's free, needs no signup, and your video never leaves your device.
- Drop or choose your MP4 file.
- Pick a bitrate and stereo or mono.
- Click Convert & Download.
- Play the preview, or save the MP3 again.
Extract audio from MP4 video
This MP4 to MP3 converter takes the sound out of a video and saves it as a standard MP3 you can play anywhere. Use it for a lecture you want to hear on a walk, a song from your own recording, or a podcast that was saved as video. Your browser decodes the audio, then a small encoder turns it into MP3 right on your device. Nothing is uploaded, and there's no watermark.
Need a shorter clip first? Trim it with the Video Trimmer, then convert it here.
Why use this free online MP4 to MP3 converter
- No upload. The video is processed in your browser, so there's no upload wait and no server copy.
- No signup or watermark. Open the page, convert, download.
- You choose the quality. Bitrates from 96 to 320 kbps, in stereo or mono.
- Preview before saving. A built-in player lets you check the result first.
Supported formats, specs and limits
| Item | Detail |
|---|---|
| Input | .mp4, .m4v and .mov files whose audio your browser can decode (usually AAC) |
| Output | MP3 (MPEG audio), constant bitrate |
| Bitrates | 96, 128, 192, 256 and 320 kbps |
| Channels | Stereo or mono |
| Max file size | 500 MB. The audio is decoded in memory, so long videos need a computer with spare RAM. |
| Sample rate | Set by your browser's audio engine, commonly 44.1 or 48 kHz |
| Not supported | Videos with no audio track, DRM-protected files, batch conversion |
For background on the container, see the Wikipedia page on MP4 file format.
Expert tips and common mistakes
Don't expect more quality than the video had
Most MP4 audio is AAC at around 128 kbps. Choosing 320 kbps won't add detail, it only makes the file bigger. For speech, 96 to 128 kbps mono is plenty.
Use mono for talks and interviews
Mono cuts the file size roughly in half with no real loss for a single speaker.
Trim first for long videos
A two-hour video can be heavy for a phone. Cut what you need first, or shrink it with Compress Video.
Convert only what you own
Use videos you made or have permission to use. This tool doesn't download from video sites.
Privacy and security
Your video is processed in your browser and never uploaded. The only network request happens when you click Convert: the page downloads the open-source lamejs MP3 encoder from the jsDelivr CDN. After that, decoding and encoding run on your device. The tool stores nothing in cookies or local storage, and closing the tab clears the file from memory.
Troubleshooting
"Could not read audio from this file"
The video may have no audio track or an unusual codec. Check that it plays with sound in your browser, or re-save it as a standard H.264/AAC MP4.
The page freezes or the tab crashes
The file is too big for your device's memory. Try a computer, close other tabs, or trim the video first.
"Could not load the MP3 encoder"
The encoder downloads from jsDelivr. Check your connection, turn off any content blocker for this page, and click Convert again.
The MP3 is silent or too quiet
The source audio may be quiet. Raise the volume in your player, or check the video's own volume before converting.
File won't load
Make sure it's an .mp4, .m4v or .mov file under 500 MB, and not a renamed file of another type.
Download didn't start
Use the Download MP3 again link under the player. If your browser blocks it, allow downloads for this site.
Frequently asked questions
Is this MP4 to MP3 converter really free?
Yes. There is no fee, no account, no watermark and no daily limit. You can convert as many MP4 files as your device can handle, one at a time.
Is my video uploaded anywhere?
No. Your video is decoded and converted inside your browser and is never uploaded. Only the small MP3 encoder library is downloaded when you click Convert.
Does converting MP4 to MP3 lose quality?
MP3 is a lossy format, so a small amount of detail is lost. At 192 kbps or higher most people can't hear a difference on everyday speakers or earbuds.
How large a video can I convert?
Files up to 500 MB are accepted. The whole file is decoded in memory, so very long videos may be slow or fail on phones and older computers.
Does it work on my phone?
Yes, in current Chrome, Safari, Firefox and Edge on iPhone, Android, Mac and Windows. Large files are safer on a computer because phones have less memory.
Why does it say my file has no audio?
Some MP4 files have no audio track, or use a codec your browser can't decode. Play the file in your browser first to check that it has sound.
Convert your MP4 to MP3 now
You don't need software or an account to turn a video into audio. Drop your file into this free MP4 to MP3 converter, pick a bitrate and download your MP3 in moments. Scroll back up to the tool and try it on your own video.