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MP4 to MP3 Converter — Extract Audio from Video Free

Extract audio from your video files as MP3, M4A, or WAV — entirely in your browser. No upload, no watermark. Works with MP4, MOV, WebM, and more.

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Drop a file here or click to browseMP4, MOV, WebM, AVI, MKV — your own video files🔒 Processed on your device — never uploaded

Ignored for WAV (lossless).

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Pull the audio out of any video — on your device

A lecture recording where only the words matter. A voice memo trapped inside a phone video. Music you produced, mixed down in a video export. Extracting the audio track is one of the oldest media tasks there is — and this tool does it with FFmpeg running inside your browser, so the file with your voice, your meeting, or your work in it never touches a server.

Your files, not the internet's

To be direct about what this tool is not: it does not download audio from YouTube, Instagram, or anywhere else, and it never will. Tools that rip platform streams operate in legal grey zones with other people's content. This converter works on files you already own — which is precisely why it can run fully offline, with no takedown notices, no link-parsing tricks, and no server in the middle.

MP3, M4A, or WAV — a thirty-second decision

MP3 at 192 kbps is the default for a reason: universally playable and transparent for most content. M4A (AAC) squeezes slightly better quality into the same bitrate — ideal inside the Apple ecosystem. WAV skips compression entirely, producing large, lossless files that editing software loves. For voice recordings, dropping to 128 kbps MP3 cuts file size by a third with no meaningful loss.

What size to expect

An MP3's size follows from its bitrate alone: 128 kbps is 0.96 MB per minute, 192 kbps is 1.44 MB and 320 kbps is 2.4 MB. A three-minute song at 192 kbps comes to about 4.3 MB; an hour-long lecture at 128 kbps to about 58 MB. WAV is roughly ten times larger (about 10.6 MB per minute for CD-quality stereo), which is the price of keeping every bit of the decoded audio for editing.

The limits, stated plainly

Converting to MP3 or M4A is lossy, and most video soundtracks are already compressed, so you are compressing twice; keep a 192 kbps or higher bitrate for music and choose WAV if you will edit the result. The tool also cannot repair or enhance a poor recording, and a video with no audio track has nothing to extract. Long files depend on your device's memory, so on a phone it is safer to extract from shorter clips.

Part of the on-device video suite

Extraction pairs naturally with the other tools here: cut the relevant span first with the video trimmer, or shrink the video itself with the compressor once the audio is safely extracted. Everything shares one in-browser engine — one download, zero uploads, no limits.

Frequently asked questions

Is my video uploaded to convert it to MP3?
No. The extraction runs on FFmpeg compiled to WebAssembly in your own browser — the engine downloads once (~31 MB), and your video is decoded and its audio re-encoded entirely on your device. Nothing is transmitted or stored anywhere.
Can this download audio from YouTube or other sites?
No, and deliberately so. This tool works only on video files you already have on your device — your recordings, lectures you've been given, your own footage. It doesn't fetch, rip, or download content from any platform.
Should I choose MP3, M4A, or WAV?
MP3 for universal compatibility — every player, car stereo, and app handles it. M4A (AAC) sounds slightly better at the same bitrate and is native on Apple devices. WAV is uncompressed and lossless — the right choice as an editing source, at about 10.6 MB per minute for CD-quality stereo (44.1 kHz) and 11.5 MB per minute at 48 kHz.
What bitrate should I pick?
192 kbps is the sweet spot for music and mixed content. 128 kbps is fine for voice — lectures, meetings, podcasts — at two-thirds the size. 320 kbps is MP3's ceiling, worth it only when the source audio is genuinely high quality.
How big will the MP3 be?
Size depends only on the bitrate and the length, not on the video: 128 kbps is 0.96 MB per minute, 192 kbps is 1.44 MB per minute and 320 kbps is 2.4 MB per minute. A 3-minute song at 192 kbps is about 4.3 MB, and a one-hour recording at 128 kbps is about 58 MB. Video files are far larger than their audio, so the MP3 is usually a small fraction of the original.
How do I turn a phone video into an MP3?
Open this page in your phone's browser, tap to choose the video from your gallery or files, keep MP3 selected and press Extract audio. The audio is processed on the phone itself and then offered as a download. Very long videos can exceed a phone's memory; if one stops partway, trim it into shorter pieces with the video trimmer first.
Is extracting the audio lossy?
MP3 and M4A are both lossy formats, and the audio in most videos is already AAC, so converting it to MP3 is a second round of compression. At 192 kbps or above the difference is rarely audible for speech and most music, but if you plan to edit the audio, choose WAV: it stores the decoded sound with no further compression.
Can I extract audio from just part of the video?
Yes. Cut the section you want with the video trimmer first, then use the "Extract audio" button next to its download link; the clip is handed over directly, with no re-selecting the file. Everything stays on your device.
Which video formats can I extract audio from?
Anything FFmpeg reads: MP4, MOV, WebM, AVI, MKV, 3GP, and most phone and camera formats. Audio-only inputs work too — you can use this tool to convert between MP3, M4A, and WAV directly.

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