MP3 to MP4 Converter | Turn Audio into Video Free

Convert MP3 audio files to MP4 videos instantly in your browser. Add custom cover images to your music for YouTube uploads. 100% private and secure.

Click for theater mode

Drop Audio file here

Supports .mp3, .wav, .m4a

Drop Cover Image (Optional)

Supports .jpg, .png (Defaults to black)

100% Local processing. Files never leave your device.

How to Use

  1. Upload your MP3 or audio file into the dropzone.
  2. (Optional) Upload a JPG or PNG image to use as the background cover for your video.
  3. Click "Convert to MP4 Video" and wait for your browser to encode it locally.
  4. Download your new MP4 file, ready for publishing.

Core Features

Perfect for Social Media

Video platforms like YouTube, Instagram, and Facebook do not accept raw audio uploads. This tool bridges the gap by easily converting your podcasts or music into a compatible video format.

Custom Background Images

Upload your own album art, podcast logo, or photo to serve as the static video background. If you don't have one, we'll automatically generate a clean, default background.

100% Private & Secure

Ideal for unreleased music or private voice recordings. The conversion happens entirely on your device using WebAssembly technology. Your files are never uploaded to any external servers.

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Calculation Logic

This tool runs an embedded video encoder (FFmpeg WebAssembly) directly inside your browser. It takes your audio track and pairs it with the static image you provided, encoding them together into a standard MP4 container. You get desktop-software-grade encoding without ever uploading your files to a cloud server.

FAQ

Can I upload this MP4 straight to YouTube?

Yes! The output is a standard MP4 file encoded with H.264 video and AAC audio, which is highly optimized and accepted by all major video sharing platforms.

Why does the conversion take a while for long audio?

Video rendering is a computationally heavy task. To guarantee 100% privacy, the rendering is done entirely by your device's CPU rather than a massive cloud server. It might take a bit longer, but your files remain completely secure.

What happens if I don't upload a cover image?

That is perfectly fine. The tool will automatically generate a solid black background image to pair with your audio, ensuring the resulting MP4 is still a valid video file.