Step 1: Drop your MP4 files using the button above or by deposit and leave.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Receive your converted AIFF files.
MP4 to AIFF Conversion FAQ
Is the MP4 to AIFF converter free?
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Yes. One conversion an hour is free, with no account needed, for a file within the free size limit. A paid plan removes the hourly limit and the size limit, and lets you add several files to one job.
Does converting MP4 to AIFF improve the audio quality?
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No, and it is worth being blunt: nothing can. The MP4 already discarded detail during its original encode, and wrapping what remains in a lossless AIFF preserves exactly that — no more. The file gets several times larger and sounds identical. It is still the right move before editing, because AIFF will not add a second generation of artefacts when you export. AIFF is the studio interchange format on macOS, handles metadata better than plain WAV, and imports into Logic and Pro Tools instantly. MP4 only supports one widely-honoured subtitle format (mov_text), and multi-track audio is unreliable outside desktop players.
Can I tag the AIFF with artist and album information?
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Yes, and it is a genuine gain over MP4, which has nowhere dependable to store any of it. AIFF carries title, artist, album, year, track number and embedded cover art in the container itself, so a music library files it correctly without a manual pass.
Will the AIFF play in my car or on older hardware?
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Often not. MP4 is decoded by essentially everything, including car head units and elderly players; AIFF needs software that knows the codec, which standalone hardware frequently does not have. If the destination is a car stereo or a portable player, that is a strong argument for staying on MP4. AIFF is as large as WAV with worse support outside the Apple world, so it is a poor choice for distribution.
How big an MP4 file can I convert to AIFF?
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Free conversions have a size limit per file, set by the type of file, and the page tells you when a file is over it. A paid plan removes that limit, so much larger files can be converted.
Can I convert many MP4 files to AIFF at once?
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Several files in one job need a paid plan. Free use is one file per conversion, one conversion an hour. On a paid plan you can add several files to one job, then download each result on its own or all of them in one ZIP.
Does the MP4 to AIFF converter work on phones and tablets?
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Yes — the UI is responsive and the conversion pipeline runs server-side, so mobile devices upload-then-download just like desktops. iOS and Android browser file pickers (camera roll, Files app) work end-to-end.
Which browsers does the MP4 to AIFF converter support?
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Chrome, Firefox, Safari (15+), Edge, and Opera. The converter uses standard `<input type="file">` upload — no WebAssembly or PWA dependencies — so even older browsers work.
Are my MP4 files kept private?
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Yes. Uploaded MP4 files are processed on our own servers and are never viewed or shared. Uploads and results are deleted automatically about 24 hours after conversion. See /privacy/ for the full policy.
What if the AIFF download doesn't start automatically?
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Disable any pop-up blocker, then click the download button manually. The result link stays active for 24 hours, so if your network fails mid-download, you can re-trigger from the result page without re-uploading the MP4.
