NoCloud Media

Video tool

MP4 to MP3 Converter

Extract audio from any MP4 video. Free, fast, and your file never leaves your browser.

How it works

  1. 1

    Drop your MP4

    Drag an MP4 file onto the converter, or click to pick one. Files stay on your device.

  2. 2

    Choose MP3 quality

    Pick a bitrate from 128 kbps to 320 kbps. Higher is better audio, larger file.

  3. 3

    Convert in your browser

    Conversion runs locally via WebAssembly. Nothing uploads, nothing queues, nothing waits on our servers.

  4. 4

    Download the MP3

    Save the result. Your original MP4 was never transmitted anywhere.

Why use MP4 to MP3?

Private by design — your video never reaches a server, so there's no risk of leaks, logs, or third-party access to your files.

Faster than upload-based tools — skip the round trip. Conversion starts instantly and runs at your device's speed.

No sign-up, no watermarks, no ads on the output. It works the same on desktop and mobile browsers.

Common use cases

  • Save a podcast episode from a video recording as MP3
  • Rip a song from a music video to listen offline
  • Extract audio from a recorded lecture for note-taking
  • Pull voice memos out of a screen recording
  • Convert an interview video to MP3 for transcription
  • Archive audio from old home videos without the visuals

About MP4 and MP3

MP4 is a container format that bundles video (typically H.264 or HEVC) with audio (usually AAC). MP3 is a lossy audio-only format supported on virtually every device and platform. Converting MP4 to MP3 means decoding the AAC audio track and re-encoding it as MP3, discarding the video entirely. NoCloud Media uses FFmpeg.wasm to do this locally in your browser — the same library used by professional video editors, running entirely on your device.

Frequently asked questions

Is my MP4 uploaded to a server?
No. NoCloud Media converts your file entirely in your browser using WebAssembly. Your MP4 never leaves this tab.
What's the maximum file size I can convert?
It depends on your browser's available memory. Files up to 500MB work smoothly on most devices; files up to roughly 2GB may work on desktop browsers with enough RAM.
Will the audio quality match the original?
MP3 is a lossy format, so re-encoding always loses some detail. At 320 kbps the difference is inaudible to most listeners. For a bit-perfect copy, use our Extract Audio tool with a lossless format like WAV or FLAC.
Can I batch-convert multiple MP4s at once?
NoCloud Media converts one file at a time to keep browser memory usage predictable. Drop the next file when the first finishes.
Does this work on mobile?
Yes — NoCloud Media runs in any modern mobile browser. Expect slower conversion on phones than on a laptop, especially for large files.
Which browsers are supported?
Chrome, Edge, Firefox, and Safari 15+. We require WebAssembly and SharedArrayBuffer, both standard in modern browsers.

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