AIFC to AAC Converter

Convert AIFC to AAC Online

AIFC is Apple's AIFF-C container, introduced in July 1991 as the compression-capable variant of AIFF (Apple, 1988, built on Electronic Arts' IFF format). It is a Mac-native file that Windows and Android tooling often refuses to open, and when it holds plain PCM it is enormous — roughly 10.6 MB per minute of 44.1 kHz 16-bit stereo. AAC solves both problems: standardized as ISO/IEC 13818-7 in 1997 and extended as MPEG-4 Part 3 in 1999, it plays on essentially every phone, browser, car head unit, and streaming client, and 128 kbps AAC works out to about 0.96 MB per minute — an order of magnitude smaller than the source.

How to Convert AIFC to AAC

1. Upload Your AIFC File: Drag your .aifc onto the page or click "+ Add Files" to browse. Queue several files to convert them all with the same settings in one batch.
2. Pick a Bitrate: File Compression opens on Quality Preset — the hands-off mode, with nothing pre-selected in its dropdown and the least predictable result on the page. Use Constant Bitrate for a fixed rate that maps one-to-one onto the encoder (the dropdown runs from 8 kbps to 384 kbps and opens on 128 kbps; 192-256 kbps suits music, 64-96 kbps spoken word), Variable Bitrate for the AAC quality ranges (20-32 kbps up to 96-112 kbps), or Specific file size to hit a byte budget.
3. Set Audio Channel, Sample Rate, or Trim: Leave Audio Channel and Audio Sample Rate on "ORIGINAL" to match the source, or fold to "MONO" and drop to a lower rate for speech. Trim takes a start time and a duration if you only need part of the recording.
4. Convert and Download: Click Convert and save the .aac file, individually or as a ZIP for a batch. No sign-up, no watermark.

Which Bitrate for Which Source

The right number depends far more on what is inside the AIFC than on the size of the file. A telephony-era μ-law recording has no high frequencies to preserve; a CD rip has plenty.

Note that the Variable Bitrate ranges offered for AAC stop at 96-112 kbps. For anything above that, use Constant Bitrate and pick the rate directly.

AIFC vs AAC

Frequently Asked Questions

Will I lose quality converting AIFC to AAC, and how much?

It depends on what the AIFC actually contains, which is the whole point of the AIFF-C format. If the compression type is NONE or sowt — plain PCM, which is what modern Mac apps write — then AAC is a clean first-generation lossy encode from a lossless master, and at 192-256 kbps most listeners cannot distinguish it from the source. If the AIFC already holds μ-law, A-law, IMA ADPCM, or MACE, the audio was thinned once before you ever touched it; AAC will faithfully reproduce what is there but cannot rebuild what the earlier codec threw away, and a very high bitrate just wastes space on artifacts.

Does this produce a raw .aac file or an .m4a, and does it matter?

This page produces .aac, which is normally an ADTS stream: a plain sequence of AAC frames with no container wrapped around them. It plays fine, but ADTS has no metadata layer, so title, artist, album, and cover art have nowhere to live. If you are building a music library or want tags and artwork to survive, use AIFC to M4A instead — .m4a is the same AAC audio inside an MP4 container, which is what iTunes, the Music app, and most players expect for tagged files.

Why does my AIFC open on a Mac but not on Windows or Android?

Because AIFC is an Apple format with an uncommon extension and an unusual payload. QuickTime, the Music app, and Finder handle .aifc natively; many Windows players, most Android apps, and browser <audio> elements either do not register the extension or lack a decoder for the legacy compression types inside it — MACE 3:1 and 6:1 in particular are effectively dead outside classic Mac tooling. VLC and Audacity will usually open one on Windows. Converting to AAC removes the dependency entirely, since AAC decoding is built into every current phone, browser, and operating system.

Is AAC or MP3 the better target for an AIFC file?

AAC, in almost every case. It was designed as MP3's successor and generally achieves higher sound quality at the same bitrate, and it is the native audio format across iOS, Android, YouTube, and most streaming services. MP3 wins on one axis only: raw ubiquity on very old hardware, where some 2000s-era players, car decks, and embedded devices predate wide AAC support. If you know the file has to work on an old device, convert AIFC to MP3 instead.

My AIFC is huge — how much smaller will the AAC be?

Between five and eleven times smaller for a PCM source, depending on the bitrate you pick. Uncompressed 44.1 kHz 16-bit stereo audio runs about 10.6 MB per minute regardless of what is in it, so a three-minute track is about 31.8 MB as AIFC PCM. The same three minutes at 128 kbps AAC is about 2.9 MB, and at 256 kbps about 5.8 MB — that is simple arithmetic from the bitrate, since 128 kbps is 0.96 MB per minute. If the AIFC already used a compression type such as IMA ADPCM, the starting file is smaller and the savings are correspondingly less dramatic.

Can AAC preserve my file's metadata, loop points, or markers?

Only some of it, and not automatically from AIFC's chunk structure. AIFF-C stores names, authorship, annotations, and comments in NAME, AUTH, ANNO, and COMT chunks, plus instrument and marker chunks used by samplers. A raw ADTS .aac has no metadata layer at all, and even an .m4a carries only standard MP4 tags — loop points and sampler markers do not survive. If those markers matter, keep the original .aifc alongside the compressed copy, or stay lossless with AIFC to AIFF.

Can I convert several AIFC files, or just part of a long one?

Both. Drop multiple files on the page and they run through identical settings, downloadable individually or as a single ZIP. For a single long recording, the Trim control takes a start time and a duration in plain seconds or as HH:MM:SS.sss, which is worth using before you upload a large PCM file — with AIFC PCM running about 10.6 MB per minute, upload time is usually the slowest part of the job, not the encode.

What happens to my uploaded files?

Files are uploaded over an encrypted connection, converted on our servers, and deleted automatically a few hours later — no sign-up, no watermark, never shared or made public. If you would rather not compress at all, AIFC to AIFF gives you plain uncompressed PCM in a container that non-Apple editors accept, and AIFC to FLAC gives lossless compression that typically halves the size with no quality change.