Video to MP3

What it does

Video to MP3 re-encodes one selected audio track to a 48 kHz, 192 kbps CBR MP3. There is no quality slider and no loudness normalization.

The conversion is lossy. It does not keep the original audio frames, tags, chapters, or cover art.

Your media file stays on your device.

Local, on-device conversion.

No account required.

Free to use during Beta.

Supported input

Support is decided from the file contents, not from the filename extension. The current public range is MP4 or MOV containing AAC-LC, and WebM containing Opus.

Mono stays mono. Stereo stays stereo. Standard 5.1 is downmixed to stereo with a versioned matrix, and the LFE channel is discarded. Other channel layouts are refused before transcoding.

A file with more than one audio track shows each track's language, title, channel layout, and default flag. A declared default is pre-selected. If no track is the default, you have to choose one. Choosing a track does not start conversion.

Limits that are not set

There is no public file-size limit, duration limit, or timeout yet. Those numbers have to come from the lowest accepted devices, and those devices have not been measured.

Cloud measurements, including any file that finished or failed on a virtual machine, are not a support promise and do not set the public limit.

2,147,483,647 bytes is an addressing boundary of the current single-buffer path. It is not a promise that a file of that size can be converted.

How a task moves

The processing page prepares the converter, inspects the video, converts the selected track, verifies the MP3, and only then offers save. Prepare, inspect, and verify do not show a fake percentage. Conversion shows elapsed time and an approximate percentage that stays at or below 99% until verification succeeds.

Save completed means the verified file was written to the chosen target and that file was closed. A browser download can only be called Download started.

You can cancel preparation or inspection immediately. Conversion and verification ask you to confirm, and the default action is to continue. Cancellation drops partial work. One manual retry starts from the original file. The same input is not retried again after that second failure.

When a file is refused

The page refuses, before transcoding, a container that is not MP4, MOV, or WebM; an audio codec other than AAC-LC in MP4/MOV or Opus in WebM; an AAC profile other than AAC-LC; a channel layout other than mono, stereo, or standard 5.1; a file with no audio track; a truncated audio track; and a file with no finite positive duration.

A refused file does not produce a saveable MP3. The message names the reason and the next step.

Privacy data flow

The video you select for conversion is processed on your device. OfflineMP3 does not upload that file to its own server in order to convert it. Your media file stays on your device.

That boundary does not cover advertising, diagnostics, or a remote media request you explicitly start. This draft loads no ad script, no ad consent module, and no third-party analytics.

A future content page may ask a same-origin gate whether one manual ad is allowed. Advertising eligibility fails closed unless the production domain, a United States region estimate, your privacy choice, and the gate all agree. Unknown region, a preview domain, an error, or a timeout means no ad request. The gate is not built in this draft. The region estimate is not a legal location guarantee.

Diagnostics stay off unless you choose to share one privacy-minimized diagnostic event for that finished task. Sharing it is still a disclosure. This draft does not send one, and it does not give that event a stronger privacy label. The privacy policy describes the event and the diagnostic deletion credential.

Not a public release

OfflineMP3 is in public Beta. It is not a technical Go or a product Go. The privacy policy, terms, about page, and contact page are drafts and need review by a qualified professional before any public release.

The privacy policy, terms, about page, and contact page on this site are drafts. Still required before any public release: a technical Go, a product Go, review by a qualified professional, and the launch checks for advertising eligibility and diagnostic deletion. This site does not load an ad script and does not run a diagnostic service.