MP3 to MP4 converter

Turn an MP3 into an MP4 video in your browser. Produces a black 640×360 picture with your audio — read below before uploading it anywhere.

Runs on your deviceFree, unlimited

Drop files here

Accepts .mp3 · Up to 20 files at a time · up to 1.4 GB each "Upload" and "download" here mean your browser reading a file from this device and writing one back to it. Nothing is sent to a server — open your browser's network panel and watch: no request carries your file.

Audio quality

FAQ

Can I use my own cover image?

Not here. The video is a solid black frame. Adding artwork means compositing a real video, which needs an editor — this conversion is only for getting audio through a form that demands a video file.

Will YouTube accept it?

Yes, it is a valid MP4 with H.264 video and AAC audio. Whether a black video suits what you are posting is a separate question — for music uploads most people add artwork first.

How large is the result?

Barely larger than the MP3. A static black frame compresses to almost nothing, so nearly all of the file is the audio, which is re-encoded to AAC.

Is the audio quality affected?

Slightly. MP4 does not carry MP3 in a form most players expect, so the audio is re-encoded to AAC — a second lossy pass. At 192 kbps or above this is not audible.

Why is the video only 640×360 and 10 fps?

Because nothing is moving. A larger frame or higher rate would add file size and encoding time without changing a black picture in any way.

Is it really free?

Yes — every conversion on this site, with no account, no watermark and no daily cap. The work happens on your own device, so there is no server bill for us to pass on to you.

Do I need to install anything?

No. It runs in any modern browser, on Windows, macOS, Linux, Android and iOS. There is nothing to download and nothing to sign up for, and once the page has loaded it keeps working with the network switched off.

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