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mp3fy

Files never leave your device. Any size, any length.

F4V to MP3.
No size, no length limits.

Flash-era MP4 variants; extract the audio.

F4V to MP3, without limits

On your device

Flash MP4 files (MPEG-4) usually carry AAC audio and come from legacy streaming. Flash-era MP4 variants; extract the audio.

How it works

  • Drop the F4V file on this page (or choose it). Folders and many files at once are fine.
  • The audio is decoded and encoded to MP3 right here in your browser — your file is never uploaded.
  • Live progress shows speed and time left; when it’s done, save the MP3 or download everything as a ZIP.

Frequently asked

Is my F4V file uploaded?

No. F4V files convert inside your browser; nothing leaves your device.

Is there a file size or duration limit?

No. mp3fy streams the file while converting, so a 20 GB recording or a 10‑hour lecture works the same as a short clip.

What bitrate should I pick?

192 kbps is the sweet spot for music and speech; 128 kbps for voice notes and podcasts; 320 kbps if you want the maximum. You can also keep stereo or down‑mix to mono.

Are my tags and cover art kept?

Yes — title, artist, album and embedded cover art are carried over into the MP3 when the source has them.

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