Add your AIFF file
Drop one or more .aiff files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
AIFF to AAC
Re-encoding .aiff audio as .aac changes how the sound is compressed and which players will accept it. Free, private, and validated — the file never leaves your browser.
Private for supported formats — processed in your browser
Runs on your deviceConvert supported files
Drop AIFF files here
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.About converting Audio Interchange File to AAC audio
Re-encoding .aiff audio as .aac changes how the sound is compressed and which players will accept it. An .aiff file is Apple's Audio Interchange File Format, storing uncompressed PCM audio much as WAV does on Windows. Mac-based studios have exchanged .aiff masters for decades, and Logic Pro sessions and sample libraries remain full of them.
An .aac file holds raw Advanced Audio Coding data, usually as an ADTS stream. AAC was designed as MP3's successor and delivers audibly better quality at the same bitrate, though the bare .aac extension is rarer than AAC audio traveling inside .m4a or .mp4 files. For this route the practical draw is noticeably more efficient than MP3 at equal bitrates and hardware decoding in essentially every phone and TV — balanced against raw ADTS files handle tags and cover art poorly, which is worth knowing before you commit a large batch.
Why convert AIFF to AAC?
The practical trigger for this conversion is usually a mismatch: with .aiff, as bulky as any uncompressed format. Switching to .aac buys you noticeably more efficient than MP3 at equal bitrates, which is why it is the better fit for receiving the audio track copied out of MP4 video without re-encoding. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
AIFF vs AAC at a glance
| Aspect | Audio Interchange File (.aiff) | AAC audio (.aac) |
|---|---|---|
| Format type | Lossless — every pixel or sample is preserved exactly | Lossy — discards detail it judges invisible to shrink files |
| How it stores data | classic AIFF stores big-endian PCM, the opposite byte order from WAV, in COMM and SSND chunks | a pure MDCT transform codec, free of the hybrid filterbank compromise that limited MP3 |
| Strongest at | delivering masters from macOS-based studios | receiving the audio track copied out of MP4 video without re-encoding |
| Weak spot | as bulky as any uncompressed format | raw ADTS files handle tags and cover art poorly |
| Metadata | nAME, AUTH, and ANNO chunks provide basic text, marker and instrument chunks store loop data, and an ID3 chunk is a common unofficial extension used by iTunes | no standard tag container exists for raw ADTS streams; ID3 tags are sometimes prepended but poorly supported, so wrapping in .m4a is the reliable way to tag AAC |
Pick AAC as the output
Select .aac in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if AAC is selectable, the route is real and validated.
Convert on your device
Press Convert. The transcode runs on an FFmpeg engine compiled to WebAssembly, so the audio never leaves your device.
Verify and download
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid AAC file. Outputs keep the original filename with the .aac extension.
AIFF to AAC questions, answered
Will converting AIFF to AAC lose quality?
Some. Since aiff is lossless-oriented and aac is lossy-oriented, the encoder will discard detail it judges least visible; the quality slider controls how aggressive that is. Keep the original .aiff if you may need a pristine master later.
Is it private to convert AIFF files here?
Yes — the .aiff file is processed inside your browser tab and never uploaded. The transcode runs on an FFmpeg engine compiled to WebAssembly, so the audio never leaves your device. Close the tab and the file is gone from memory.
Where will the AAC file work?
AAC decoding is built into every browser, phone, and operating system, whether the audio arrives as a raw .aac stream or inside an .m4a wrapper. The last holdouts are elderly MP3-only car stereos and bargain portable players.
Will the AAC file be bigger or smaller than my AIFF?
Smaller, usually dramatically so — that is the main reason this route exists. The quality slider trades size against fidelity; the default sits at the point where most people cannot spot the difference.
What happens to the metadata in my AIFF file?
This converter strips container metadata deliberately (the FFmpeg command runs with metadata mapping disabled) so exported files do not leak recording details. In the source, nAME, AUTH, and ANNO chunks provide basic text, marker and instrument chunks store loop data, and an ID3 chunk is a common unofficial extension used by iTunes; none of it is transmitted anywhere because the file never leaves your browser.
Can I convert AAC back to AIFF?
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .aiff → .aac → .aiff is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.