MP4 to MP3. Extract the audio.
Save the sound of a video as an MP3, or copy the original soundtrack out untouched. On your device, nothing uploaded.
How do I convert MP4 to MP3 for free?
Drop the video into Cutmallow's free audio extractor above with MP3 selected. Your browser decodes the soundtrack and encodes it as a 192 kbps MP3 on your device, ready to save. To keep the sound exactly as recorded, choose Original sound instead: it is copied out without re-encoding (an M4A for most MP4s). Nothing is uploaded, and there's no watermark or length limit.
Updated
- MP3 bitrate
- 192 kbps
- Original sound
- No re-encode
- Sample rate
- Up to 48 kHz
- Length limit
- None
How to use it
Pick MP3 (plays everywhere) or Original sound (no re-encoding).
Drop a video, or tap to pick one.
Save the audio file when it is ready.
How it works
A video file holds a video stream and a sound stream side by side. The extractor reads only the sound packets, a piece at a time, so even a long video never has to fit in memory, and leaves the picture behind.
With MP3, the sound is decoded by your browser’s built-in audio decoder and encoded with the LAME MP3 encoder (lame.sourceforge.io), compiled to WebAssembly and running in a background thread. 192 kbps is clean for voice and music on phones and laptops.
With Original sound, nothing is decoded: the encoded sound packets are copied into the audio file that fits them, so the result is bit-for-bit the soundtrack you recorded. Both modes run entirely on your device, built on the open-source Mediabunny media library. Your video never leaves your device.
Tips for a better result
- Pick Original sound when quality matters most: nothing is re-encoded.
- Pick MP3 for podcast apps, music players and older editors: it opens everywhere.
- On iOS before 26, choose Original sound. MP3 needs the newer audio decoder.
Turn it into a Short
Cutmallow's free editor finishes the job. After extracting, tap Edit in Cutmallow and the video opens there, still on your device.
- Cuts the pauses and filler words
- Writes animated word-by-word captions
- Exports a 9:16 MP4 for Shorts, Reels and TikTok
Frequently asked questions
Something else? Write to [email protected].
How do I extract audio from a video?
Choose MP3 or Original sound above, drop the video and save the file when it is ready. It works the same for MP4, MOV, M4V, MKV and WebM, and the video itself is not changed.
Should I pick MP3 or Original sound?
Pick MP3 when you need a file that opens anywhere, such as a podcast app, a music player or an older editor. Pick Original sound for the best quality and speed: nothing is re-encoded, and most phone videos give an M4A, which iPhones, Macs, Windows and Android all play.
Can I extract audio from a video on iPhone?
Yes, in Safari. MP3 needs iOS 26 or later; on older iOS choose Original sound, which needs no decoding. Tap Save audio and the share sheet offers Save to Files.
Is my video uploaded anywhere?
No. Your video never leaves your device. The file is opened and processed by your own browser, and the result is saved straight from your device.
Is there a file size or length limit?
No. The file is read from your device a piece at a time and the result is written to the browser’s private storage, so long and very large videos work. The only limit is free space on your device.