Step 1: Supply your AAC files using the button above or by haul and lay.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Get your converted AIFF files.
AAC to AIFF Conversion FAQ
What does the AAC to AIFF audio converter do?
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AAC is already lossy, so converting to AIFF preserves the existing audio without further degradation, but it cannot recover detail lost in the original encode. AIFF is right if you plan to edit and resave without compounding compression artifacts.
Will the AIFF file be much larger than the source AAC?
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Yes — lossless audio is typically 5-10x larger than lossy audio at perceptually equivalent quality. Plan for ~10 MB per minute for AIFF versus ~1 MB per minute for high-bitrate AAC.
Does converting AAC to AIFF improve the audio quality?
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No, and it is worth being blunt: nothing can. The AAC 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. AAC is patent-encumbered, and a handful of very old players still refuse it where they would accept an MP3.
What exactly is an AIFF file?
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A container with the audio inside it, rather than the audio on its own. That extra layer is where the length, the seek index and whatever metadata the format defines are kept, so a player knows how long an AIFF is before decoding a single frame instead of scanning the whole file to find out. It also means the extension does not always settle what is inside: several containers of this kind are allowed to hold more than one sort of audio, which is why two AIFF files can behave differently while looking identical from outside. AIFF stores uncompressed big-endian PCM — the Apple-side equivalent of WAV, with the same bit-for-bit fidelity.
Why did my phone or tablet record in AAC?
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Because it is what the hardware encoder on the device produces. Voice memos, screen recordings and the audio track of anything filmed on a phone come out as AAC without anyone choosing it, which is why so many files arrive in it and why the quality is usually better than the file size suggests. Nothing about that stops it converting; it just means the source was encoded once already, by a chip optimised for battery life rather than for fidelity. AAC is Advanced Audio Coding, standardised in 1997 as MPEG-2 Part 7 and designed explicitly to replace MP3.
Will the AIFF play in my car or on older hardware?
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Often not. AAC 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 AAC. AIFF is as large as WAV with worse support outside the Apple world, so it is a poor choice for distribution.
Is there a licence attached to AAC?
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Not one you have to think about. The codec is covered by patent pools, and the licensing is settled by whoever ships the decoder — the phone, the browser, the operating system — long before a file reaches you. It is why the format is everywhere in hardware, and why royalty-free alternatives were built at all. It changes nothing about converting a file you already have, and it is only a live question if you are shipping an encoder yourself.
Is AIFF still a sensible thing to convert to?
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For a personal library, yes; for anything you are handing to somebody else, think twice. AIFF is being quietly succeeded rather than switched off — everything that plays it today will carry on playing it — but new encoders and new devices increasingly default to its replacement, which does the same job at least as well. If the file only has to open on your own machines, it is fine. If it has to open on a device bought in five years, pick the newer one.
Is there a file-size limit when converting AAC 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 batch-convert several AAC 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.
What happens to my AAC files after the conversion?
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Uploaded files are processed on our own conversion servers, nobody looks at them, and they are not shared. The upload and the converted file are both deleted automatically about 24 hours after the conversion, which leaves time to download the result. See /privacy/ for the full policy.
What apps can play a AIFF file?
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AIFF plays in most music players, browsers, and media libraries. iTunes / Apple Music, VLC, Foobar2000, and phone media apps handle it natively.
