How do I convert AAC to AIFF?

Add your AAC file to the upload area above, then press Convert. The AIFF file downloads straight to your device. You do not need an account, and there is no watermark.

Are my files uploaded to a server?

No. This conversion runs entirely inside your browser using WebAssembly, so the file never leaves your device — you can even disconnect from the internet after the page loads and it will still work.

Does converting to AIFF reduce quality?

No. AIFF is a lossless format, so the conversion preserves exactly what is in your AAC file. Note that it cannot recover detail that was already discarded when the AAC was first created — a lossless container does not undo earlier compression.

How large a file can I convert?

Up to 300 MB per file for this conversion. Because the work happens in your browser, the practical limit is your device's memory — larger files work on a desktop with plenty of RAM and may fail on an older phone.

Can I convert several files at once?

Yes. Add as many as you like and press Convert All. Each file is processed independently, so one failure does not stop the rest, and you can download everything together as a ZIP.

Can I use this on my phone?

Yes. FileTools360 works in mobile browsers on iOS and Android, including choosing files straight from your camera roll. Very large videos may run out of memory on a phone — those are better converted on a laptop.

AudioLosslessRuns in your browser

AAC to AIFF Converter

Turn AAC files into AIFF in a couple of clicks. The successor to MP3 — better quality per bit. Apple's uncompressed audio counterpart to WAV. The conversion is lossless — every pixel, sample or byte in the source is preserved.

On your deviceNever uploadedGone when you close the tabHow this works

Drop your files here

AAC files (.aac, .adts) · up to 300 MB each

or paste files from your clipboard

Ready when you are

Drop a AAC file above and FileTools360 will turn it into AIFF — right here on your device, without uploading anything.

⌘K to search converters

How to use it

1
Add your AAC files
Drag them onto the upload area, choose them from your device, or paste them from your clipboard. You can queue several at once.
2
Adjust the settings if you want to
The defaults suit most people. Open Advanced to control bitrate, sample rate and channels and start and end times.
3
Convert and download
Press Convert. Everything happens on your own device — nothing is uploaded. Download files one by one, or grab them all as a ZIP.

AAC and AIFF explained

AAC is the successor to MP3 and is the default audio codec for MP4 video, Apple Music and YouTube. At the same bitrate it generally sounds noticeably better than MP3.

AIFF is Apple's uncompressed audio format, functionally equivalent to WAV but with better metadata support and big-endian byte order.

Where AAC files come from: Streaming services, video soundtracks and Apple devices.
Where AIFF is used: Mac audio production and older Apple software.

AAC vs AIFF

The two formats solve different problems, which is why converting between them involves trade-offs rather than a straight upgrade.

AAC compared with AIFF
Property	Source	Target
Compression	Lossy	Uncompressed
Introduced	1997	1988
Browser support	Excellent across modern devices.	Strong on Apple, decent elsewhere.

AAC is stronger at: Better quality per bit than MP3. The standard audio track for MP4 video. Excellent device support.
AIFF is stronger at: Uncompressed and lossless. Better metadata handling than WAV. Standard in Mac audio workflows.

Why convert AAC to AIFF?

People make this switch when they run into the limits of AAC: archiving, or targeting very old playback hardware. AIFF is the better fit when audio production on a Mac.

Be aware of the size trade-off: AIFF is uncompressed, so expect the converted file to be considerably larger than the AAC you started with.

AAC limitations that prompt the switch: Still lossy. Patent licensing applies to encoders. Slightly less universal than MP3 on very old hardware.
What you give up: Very large files. Less universally supported than WAV.

Does converting AAC to AIFF reduce quality?

Going from AAC to AIFF moves already-compressed data into a format that stores it exactly. Nothing is lost from this point on, but nothing is recovered either — the detail AAC discarded when the file was first created is gone permanently. Expect a noticeably larger file for identical visual quality.