Convert AIFF to MP3 without uploading anything
This AIFF to MP3 converter turns the big uncompressed files that Mac software produces into MP3s that play everywhere and fit in an e-mail. Drop in a GarageBand or Logic bounce, a sample pack, a CD imported in AIFF format or an old file from a Macintosh, choose a bitrate up to 320 kbps and press Convert. Several files can go through in one pass, and you download them one by one or as a ZIP.
Chrome, Edge and Firefox cannot open AIFF files on their own, so this page carries its own small AIFF reader written in JavaScript. It understands plain AIFF and the AIFF-C variants you meet in practice: big- and little-endian PCM from 8 to 32 bits, 32- and 64-bit floating point, μ-law and A-law, and IMA ADPCM (“ima4”). The decoded audio goes straight to LAME, the open-source MP3 encoder, running in the same browser tab. Nothing is sent to a server.
How to use the AIFF to MP3 Converter
- Drop your .aiff, .aif or .aifc files on the box, or click it to choose them. Each file shows its format, bit depth, sample rate, channels and length.
- Leave Convert to on MP3, or pick M4A, WAV, FLAC or OGG if you need another format.
- Choose the Quality. 320 kbps is preselected because AIFF is lossless; 192 kbps is enough for most listening.
- Keep Copy title, artist, album and cover art ticked to carry the AIFF name, author, comment and ID3 tags into the MP3.
- Press Convert, listen to a result with Play, then press Download or Download all (ZIP).
AIFF to MP3 Converter features
Reads AIFF that browsers cannot
A built-in parser handles AIFF and AIFF-C: PCM (NONE, twos, sowt, in24, in32, raw), float (fl32, fl64), μ-law, A-law and IMA4 ADPCM, at any sample rate and channel count.
MP3 up to 320 kbps
Constant-bitrate MP3 from 64 to 320 kbps, encoded with LAME. Surround files are mixed down to stereo.
Tags carried across
AIFF NAME, AUTH, ANNO and copyright chunks become ID3 title, artist, comment and copyright; an embedded ID3 chunk (as written by iTunes and Music) is copied byte for byte, cover art included.
Batch and ZIP
Convert a whole folder of stems or a ripped album in one go.
Other targets too
Save as WAV (16-bit, 24-bit or 32-bit float), FLAC, M4A or OGG instead of MP3.
Honest about odd files
Rare compressed AIFF-C types such as MACE or QDesign are passed to FFmpeg after you agree to a 32 MB download, and unknown ones are named so you know what to re-export.
AIFF, AIF, AIFF-C: what you might have
AIFF (Audio Interchange File Format) was published by Apple in 1988 and is the Mac counterpart of WAV: a container of chunks around raw, uncompressed samples, stored most-significant byte first. AIFF-C, introduced in 1991, added a compression field. Despite the name, most AIFF-C files are not compressed at all — macOS and many music apps write 16- or 24-bit PCM as AIFF-C with the “sowt” (little-endian) or “NONE” code, or 32-bit float as “fl32”.
| Code in the file | What it is | Where you see it | Handled by |
|---|---|---|---|
| NONE / twos | Big-endian PCM, 8–32 bit | GarageBand, Logic, Pro Tools, CD rips | This page |
| sowt | Little-endian PCM | macOS system audio, many apps | This page |
| fl32 / fl64 | Floating point | Logic and DAW bounces, sample libraries | This page |
| ulaw / alaw | G.711 companded, 8-bit | Telephony, voice prompts | This page |
| ima4 | IMA ADPCM, 4:1 | Old QuickTime and game audio | This page |
| MAC3 / MAC6, QDM2, Qclp, GSM | Legacy Mac codecs | Classic Mac OS files | FFmpeg (optional download) |
Which MP3 bitrate should you pick?
An AIFF from a 44.1 kHz, 16-bit source runs at 1,411 kbps — about 10 MB per minute. An MP3 at 320 kbps is roughly 2.4 MB per minute and is very hard to tell apart from the original in normal listening; 256 kbps (1.9 MB/min) is the rate most online stores use; 192 kbps (1.4 MB/min) suits phones and cars; 128 kbps is fine for speech and demos. Higher sample rates such as 96 kHz are converted to 48 kHz first, because MP3 does not go above 48 kHz.
If you need to keep every bit, choose FLAC instead: it is lossless like AIFF but about half the size, and it plays on Android, Windows and most hi-fi players. To shrink an existing MP3 further, use the MP3 Compressor; to edit its tags afterwards, the ID3 Tag Editor.
How the conversion works
- The page reads the COMM chunk for channels, sample count, bit depth and the 80-bit floating-point sample rate, then slices out the SSND sound data.
- Samples are turned into 32-bit floating point exactly: a 24-bit value of 8,388,607 becomes 0.99999988, with no rounding added.
- Old Macintosh rates such as 22,254.5 Hz are rounded to the nearest hertz; MP3 output is resampled to 32, 44.1 or 48 kHz with a windowed-sinc filter.
- LAME encodes the MP3 at a constant bitrate; an ID3v2 tag is written in front with browser-id3-writer (MIT).
AIFF to MP3 Converter FAQ
How do I convert AIFF to MP3 for free?
Drop the AIFF file on this page, keep MP3 and 320 kbps selected and press Convert. When it finishes, press Download. There is no sign-up, watermark or file limit beyond your device’s memory.
Is AIFF to MP3 at 320 kbps lossless?
No. MP3 is always lossy, but at 320 kbps the difference from the AIFF is inaudible to most people in most music. Choose FLAC or WAV if you need a lossless copy.
Why won’t my browser play AIFF?
Only Safari has a built-in AIFF decoder. Chrome, Edge and Firefox do not, which is why this page reads the file with its own JavaScript parser before encoding it.
Are my files uploaded?
No. The file is read, decoded and encoded inside your browser tab. Only the encoder programs are downloaded, from a public CDN.
What is the difference between .aif, .aiff and .aifc?
They are the same family. .aif and .aiff are plain AIFF; .aifc is AIFF-C, which may be uncompressed (sowt, NONE, fl32) or compressed. This converter accepts all three extensions.
Will the song title and artist be kept?
Yes, for MP3 output. Name, author, annotation and copyright chunks are written as ID3 tags, and an ID3 chunk already inside the AIFF is copied unchanged, including cover art.
Can I convert many AIFF files at once?
Yes. Drop several files or add more with Add files, convert them together and press Download all (ZIP).