The short version
Your files never leave your computer. MP4toMP3 converts video to audio inside your browser, using your own device's processor — there is no upload, no server-side processing and no copy of your file anywhere but your own disk. We could not hand your video to anyone if we were asked, because we never have it.
We do measure how the site and the converter are used, in aggregate, with Google Analytics. That is described in full below.
What happens to your files
When you choose, drag or paste a file, the browser reads it from your disk and decodes it locally. The audio is re-encoded locally, and the finished file is handed back to you as a download that was created on your machine. No part of this involves our servers.
- Your files are never uploaded, transmitted or stored by us.
- We never see your file names, their contents, their metadata or the audio inside them.
- Nothing you convert is retained anywhere after you close or reload the tab.
- Cover art captured from a video frame is created and kept in your browser's memory only.
- There are no accounts, so there is nothing to attach a conversion history to.
Closing the tab discards everything. If you want to keep a result, download it before you leave.
Analytics
This site uses Google Analytics 4 to understand how many people use it, which features
they use and where the tool fails them. The Google tag sets first-party cookies (named
_ga and _ga_<id>) that hold a randomly generated
identifier so repeat visits from the same browser are not counted as new people. They
last up to two years and you can delete them from your browser settings at any time.
Alongside standard page views, we record events describing how the converter performed:
- That files were selected, and how (browse, drag-and-drop or paste)
- How many files, their combined size in megabytes, and their duration in seconds
- The source audio codec, bitrate and channel count reported by the file
- The output format and quality you chose, and whether you trimmed
- Whether the conversion succeeded, how long it took, which engine did the work, and the size of the result
- Which error occurred when a conversion fails, from our own fixed list of causes
- Which links, FAQ entries and buttons were clicked
None of this includes your file: not its name, not its contents, not a fingerprint of it. "A 42 MB, 6-minute file was converted to 192 kbps MP3 in 11 seconds" is the level of detail we collect, and it is the level we need to know whether the tool is working.
Google processes this data as our analytics provider and may store it on servers outside your country. See Google's own privacy policy. You can opt out entirely with Google's opt-out browser add-on, with your browser's tracking protection, or with any content blocker. The converter works exactly the same either way — it does not depend on analytics loading.
Campaign attribution
If you arrive from an ad or a campaign link, the campaign parameters already in that URL
(utm_source, utm_medium, utm_campaign,
utm_term, utm_content, gclid) and the referring
site are saved once in your browser's local storage under the key
m2m_first_touch. They are attached to later analytics events so we can tell
which campaigns bring people who actually convert something.
This is stored on your device, contains only values that were already in the link you clicked, and is never written for a plain direct visit. Clearing your browser's site data removes it.
Server logs
Like every website, the server that delivers these pages records standard request information: IP address, browser and device type, the page requested, the time and any errors. It is used to keep the site online, diagnose faults and prevent abuse, and it is retained only as long as it is useful for those purposes. Because the conversion happens in your browser, no request for it ever reaches this server.
Third parties
Three outside services are involved in loading or running this site:
- Google Analytics — the measurement described above.
- Google Fonts — the typeface is fetched from Google's font servers, which means your IP address is visible to Google as part of that request.
- jsDelivr — if your browser cannot decode a file natively, the tool downloads a compatibility engine (about 30 MB, and it always tells you before it starts) from the jsDelivr open-source CDN. Only the engine is downloaded; your file is not sent anywhere.
We do not sell or share personal data, and we do not currently serve third-party advertising. If advertising is ever introduced, this policy will be updated before it appears.
Children
This service is not directed at children under 13, and we do not knowingly collect personal information from them.
Your rights
Depending on where you live, you may have the right to access, correct, delete or restrict the processing of personal data held about you, and to object to it. Because there are no accounts and your files never reach us, the only data we hold that could relate to you is the analytics and server-log data described above, none of which identifies you by name. You can exercise the practical equivalent yourself at any time by clearing your browser's cookies and site data for this domain, or by using the analytics opt-out linked above. To make a formal request, email us.
Changes
We may update this policy. Any change is posted on this page with a new date at the top, and continued use of the site after that indicates acceptance.
Contact
Questions or requests about this policy: [email protected]