Step 1: Share your AIFF files using the button above or by drag and drop.
Step 2: Click the 'Transform' button to start the transformation.
Step 3: Grab your converted M4A files.
AIFF to M4A Transformation FAQ
How do I convert AIFF audio to M4A without losing quality?
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Upload the AIFF file and the converter chooses the M4A codec and bitrate to match the source. Lossless M4A (WAV / FLAC / ALAC) preserves every sample bit-identically; lossy M4A (MP3 / AAC / OGG / Opus) defaults to 192 kbps which is transparent for most ears. AIFF stores uncompressed big-endian PCM — the Apple-side equivalent of WAV, with the same bit-for-bit fidelity. An M4A holds AAC in most cases, or Apple Lossless (ALAC) when it came from a lossless rip.
How much quality do I lose converting AIFF to M4A?
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Some, and it is permanent — this is the one direction where information is genuinely thrown away. AIFF holds every sample exactly; M4A discards what a psychoacoustic model predicts you will not hear. At 192 kbps and above that prediction is good enough to be transparent on most material and most equipment. Keep the AIFF as your master, because you cannot get back to it from the M4A.
What bitrate will the resulting M4A file use?
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Default is 192 kbps for lossy M4A; pass-through for lossless M4A. Override to 320 kbps for audiophile or 96 kbps for voice / podcast. The choice trades file size against audible fidelity; below 96 kbps lossy artifacts become noticeable on music.
Will going from AIFF to M4A reduce my audio quality?
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If AIFF is lossy and M4A is lossless (e.g. MP3 → WAV), the M4A is no better than the AIFF — you cannot recover information already discarded. If AIFF is lossless and M4A is lossy, the M4A codec recompresses; at 192 kbps the result is transparent for most content.
Does the AIFF to M4A converter keep ID3 / metadata tags?
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Yes — title, artist, album, year, track number, and album art are read from the AIFF container and written into the M4A container where the format supports tags. All common targets (MP3, AAC, FLAC, OGG) handle tags fine; raw WAV does not. M4A is an MP4 container carrying audio only, and it is what iTunes, Apple Music and the iPhone Voice Memos app produce.
Can I batch convert hundreds of AIFF files to M4A?
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Yes — drop a folder of AIFF files in and we process them in parallel. Premium has more parallel workers and no per-file size cap, so a 500-file batch finishes in minutes rather than tens of minutes.
Will the M4A keep the same sample rate as AIFF?
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By default yes — 48 kHz AIFF stays 48 kHz in M4A. If you need to downsample for compatibility (96 kHz → 44.1 kHz for CD burning), the sample-rate option applies high-quality resampling in the same encode pass.
Can I normalize loudness when converting AIFF to M4A?
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Yes — the loudness-normalize option applies ITU-R BS.1770 / EBU R128 normalization to the M4A, targeting -14 LUFS (streaming standard) or -16 LUFS (podcast standard). Useful when batching tracks mastered at varying levels.
Will my M4A play on car stereo, iPod, and Sonos?
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MP3 plays everywhere. AAC plays on Apple, most Android, and Sonos. FLAC plays on Sonos and Android but not on older iPods. WAV plays on everything but is huge. The advanced device-preset dropdown picks an M4A codec optimized for your target hardware. M4A keeps rich iTunes-style metadata, chapters and artwork intact, and is the native audio format across every Apple device. M4A hides two very different things behind one extension — lossy AAC and lossless ALAC — and non-Apple hardware support is inconsistent.
Is my AIFF file private during conversion to M4A?
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Yes — uploaded AIFF files are processed in isolated workers and deleted within minutes. We never play back, store long-term, or share the audio content. The full retention window is in /privacy/.
How long does converting a 1-hour AIFF to M4A take?
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Same-codec re-mux: 10 to 30 seconds. Re-encode to a different codec: typically 10 to 20% of source duration, so a 1-hour AIFF → M4A finishes in 6 to 12 minutes. Batch jobs parallelize across workers for further speedups.
Why is the M4A louder or quieter than the AIFF source?
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No automatic gain change happens unless you enable the normalize option. If you observe a level change, your audio player or media library is likely applying ReplayGain or per-track normalization on playback — not us. Disable that to hear the true M4A levels.
