Free online AIFF to M4A converter

Phones, music apps, and email attachments may reject or handle large AIFF files poorly. Converting AIFF to M4A reduces the size for sharing and playback, while AAC provides compact lossy audio and ALAC preserves the audio without loss.

What AIFF is

AIFF (Audio Interchange File Format) is an Apple-developed audio container commonly used for uncompressed PCM recordings. It preserves the source samples without lossy compression, but its files are large: stereo 44.1 kHz, 16-bit audio requires about 10 MB per minute.

Audio editors, recording applications, CD-ripping software, professional audio equipment, and older Apple software can create AIFF files. You may encounter them after exporting from Logic Pro, GarageBand, Audacity, or an audio archive. AIFF-C is a related variant that can use compression, so not every AIFF-family file is necessarily uncompressed.

What M4A is

M4A is a filename extension for audio stored in an MPEG-4 container; it does not identify one specific codec. The audio is usually AAC, which creates much smaller lossy files, or ALAC (Apple Lossless Audio Codec), which preserves the decoded audio data without lossy compression.

AAC M4A is widely supported by phones, tablets, media players, music libraries, and sharing services. ALAC M4A is suitable for lossless archiving and normally occupies less space than uncompressed AIFF, although it is larger than AAC and may have weaker support on older or non-Apple players.

Convert with 101convert.com

1. Open the AIFF-to-M4A converter on 101convert.com.
2. Select or upload the .aiff or .aif file.
3. Choose M4A as the output format.
4. If a codec or quality option is available, choose AAC for a smaller, broadly compatible file or ALAC for lossless output.
5. Start the conversion and download the resulting .m4a file.

The converter is free to use and requires no software installation. Do not upload confidential recordings unless the service's storage and deletion terms are acceptable.

Convert with FFmpeg

FFmpeg provides the same command-line workflow on Windows, macOS, and Linux. To create a widely compatible AAC M4A at 256 kbps, run:

ffmpeg -i input.aiff -c:a aac -b:a 256k output.m4a

For lossless ALAC output, run:

ffmpeg -i input.aiff -map_metadata 0 -c:a alac output.m4a

FFmpeg normally preserves the source sample rate and channel count unless you specify resampling or channel conversion. The -map_metadata 0 option copies metadata where the destination container supports the corresponding fields.

Convert with Apple Music or iTunes

Apple Music on macOS and iTunes on Windows can create AAC M4A files. In Apple Music, open Music → Settings → Files → Import Settings; in older macOS versions, use Music → Preferences → Files → Import Settings. In iTunes for Windows, use Edit → Preferences → General → Import Settings.

1. Set Import Using to AAC Encoder and choose the desired quality setting.
2. Import the AIFF file into the library.
3. Select the file and choose File → Convert → Create AAC Version.
4. Locate the new M4A file from the library's file information or storage location.

Menu names vary by application version. This workflow creates AAC, not ALAC, and the resulting file may not retain every AIFF metadata field.

Quality and compatibility

AAC conversion is lossy: information removed during encoding cannot be recovered, and repeated lossy conversions can add further degradation. Use about 192 kbps for general listening and 256 kbps when preserving higher lossy quality matters. An AAC file cannot sound better than its AIFF source.

Choose ALAC when the output must remain bit-for-bit lossless. It can reduce storage compared with PCM AIFF, but it is not as compact as AAC and may fail on players that support AAC M4A but not ALAC.

AIFF metadata may use ID3, INFO, or broadcast fields that do not map exactly to MPEG-4 metadata. Check the converted file's artist, album, title, artwork, and track number before adding it to a music library. Also verify the sample rate and channel count when a specific device or application has audio-format limits.