Convert MP4 to MP3 Online, Straight From Your Phone or PC
Drop in a screen recording, phone video or downloaded clip and save its soundtrack as an MP3 file.
Drag & drop a video, or
MP4, MOV, MKV, AVI, WebM supported
Higher kbps means better audio quality and a larger file.
A free MP4 to MP3 converter for any MP4 file
MP4 is the format most video ends up in: Android phone clips, GoPro footage, OBS and Loom screen recordings, meeting exports and anything a video editor spits out. This MP4 to MP3 converter takes the sound track out of that file and saves it as an MP3 at 128, 192 or 320 kbps. The MP3 keeps the MP4's file name, so interview.mp4 comes back as interview.mp3.
The conversion runs in your browser, on your own phone or computer. Since I don't pay for a server to process your MP4, I don't cap file size or the number of files you convert.
How to convert MP4 to MP3
1.Add your MP4
Drag the file into the tool above, or click browse. On a phone, pick it from your gallery or the Files app.
2.Choose the MP3 bitrate
192 kbps is selected by default. Drop to 128 kbps for talking, go up to 320 kbps for music.
3.Convert and save
Listen to the result right in the page, then download the MP3.
MP4 to MP3 on Android
Android phones record video as MP4, so this is the page for them. Open it in Chrome, tap browse and pick the clip from your gallery or Files. When the MP3 is ready, tap download and it lands in the Downloads folder, where music players and apps like WhatsApp can find it. Keep Chrome on screen while it converts, because Android pauses background tabs to save battery.
What's inside an MP4's audio track
An MP4 is a container: one file that holds a video stream, an audio stream and some timing data. In almost every MP4 the audio stream is AAC, which is already compressed. So converting MP4 to MP3 means decoding that AAC and encoding it again as MP3, using the LAME encoder at a constant bitrate. The video stream is skipped entirely, which is why a 2 GB screen recording turns into an MP3 of a few dozen megabytes.
Two things change on the way. MP3 holds stereo at most, so 5.1 audio from some cameras and screen recorders gets mixed down to two channels, while a mono voice recording stays mono. And most MP4s store audio at 48 kHz, the video standard. The MP3 comes out at 44.1 kHz, the rate music players and editors expect, and you won't hear the difference.
Which MP3 bitrate should you pick?
Re-encoding can't add detail the MP4 never had, so the useful question is how good the MP4's own audio is. Most phone and screen recordings store AAC somewhere between 96 and 256 kbps.
| What's in the MP4 | Pick | Why |
|---|---|---|
| Meeting, lecture, webinar, voice-over | 128 kbps | Speech sounds the same as the source, and files stay small |
| Vlog, tutorial with background music | 192 kbps | Keeps music clean without doubling the size |
| Concert, DJ set, music video | 320 kbps | Leaves the most room for the detail the MP4 still has |
To see the MP4's own audio bitrate: on Windows, right-click the file, choose Properties, then the Details tab and look under Audio. On any system, the free app MediaInfo shows it. Pick the MP3 bitrate at or just above that number. Going higher only makes the file bigger. My guide to MP3 bitrates covers the listening differences in detail.
How big will the MP3 be?
An MP3's size depends only on its bitrate and length, not on how big or sharp the MP4 was. Bitrate × seconds ÷ 8 gives you the number of bytes:
| Length | 128 kbps | 192 kbps | 320 kbps |
|---|---|---|---|
| 3-minute song | 2.9 MB | 4.3 MB | 7.2 MB |
| 30-minute podcast | 29 MB | 43 MB | 72 MB |
| 1-hour lecture | 58 MB | 86 MB | 144 MB |
| 2-hour recording | 115 MB | 173 MB | 288 MB |
If an MP3 needs to fit under an email limit of around 25 MB, a 30-minute talk at 128 kbps is right on the edge, so cut it into parts or send a link instead.
Can you just rename .mp4 to .mp3?
No. Changing the extension doesn't change what's inside the file. It's still an MP4 container holding video and AAC audio, and most players refuse to open it or show an error. Some audio apps will play an MP4 renamed to .m4a, because M4A uses the same container, but the video is still in there, so the file is just as big. To get a real, small MP3 the audio has to be decoded and encoded again, which is what the converter does.
MP4 files with more than one audio track
OBS can write up to six audio tracks into one recording, for example your microphone on one track and game or desktop sound on another. Some meeting tools and capture cards do something similar. An MP3 holds one stereo track, so the tool converts the default track, the one a normal video player plays when you press play. If the sound you want is on another track, export that track from OBS or your editor first, or change your recording settings so the mix you want lands on track 1.
Frequently asked questions
How do I convert MP4 to MP3 for free?
Add the MP4 to the tool above, pick 128, 192 or 320 kbps and click convert. You don't need an account, and you can convert as many files as you want.
Does converting MP4 to MP3 lose quality?
A little, because the AAC audio is decoded and compressed again. At 192 kbps or higher, most people can't hear a difference from the MP4.
What is the best bitrate for MP4 to MP3?
192 kbps for most files. Use 128 kbps for speech and 320 kbps for music, or match the MP4's own audio bitrate.
How do I convert MP4 to MP3 on iPhone?
Open this page in Safari, tap browse and choose the file from Photos or Files. The MP3 saves to the Files app, in Downloads. Keep Safari open until it finishes.
Does it work on Windows and Mac?
Yes. It runs in Chrome, Edge, Safari or Firefox, so there's nothing to install.
Why does it say my MP4 has no audio?
Some MP4s have no sound track at all, such as screen recordings made with the mic off, GoPro time-lapses or stock footage. There's nothing to convert, so the tool tells you instead of giving you a silent MP3.
Why does the first conversion take longer to start?
Most browsers have no built-in MP3 encoder, so the page downloads one the first time (roughly 30 MB). Your browser caches it, so later conversions start right away.
Why is conversion slow or stuck?
Your own device does the work, and a long 4K MP4 can be several gigabytes. Keep the tab open and in front. Switching apps or letting a phone lock can pause it.
Can I convert only part of an MP4?
Not in this tool. It converts the whole audio track. Trim the MP4 first, or trim the MP3 afterwards in any audio editor.
Can I convert several MP4 files?
Yes, one after another. Download the first MP3, then click convert another video and add the next MP4.
Is my MP4 uploaded anywhere?
No. Your browser decodes the AAC audio and runs the LAME encoder on your own device, so the MP4 stays on your phone or computer.
The tool says it can't read my MP4. What now?
The file is probably damaged, or it came from a capture card or old editor that writes a non-standard MP4. Export it again from the original app, or open it in VLC and use Convert/Save to write a fresh MP4.
Need WAV, M4A or a MOV file?
This page is built for MP4 to MP3. For WAV, M4A or OGG output, or for MOV files from an iPhone or camera, use the video to audio converter. Want the words instead of the sound? MP4 to transcript turns the speech into text. And if the MP4 itself is too big to send, the video compressor shrinks it while keeping the picture.