Convert AIFF to FLAC on Mac

Before you start

AIFF and FLAC are both capable of storing lossless PCM audio, so conversion normally preserves the underlying audio data without changing its quality. The main practical difference is that FLAC files are usually smaller because the audio is compressed. On a Mac, the conversion should be done locally unless you choose a third-party web service. Check where the AIFF files are stored, confirm that you have enough free disk space for the new FLAC versions, and keep the original AIFF files until the output has been verified.

Step-by-step instructions

One straightforward local method is to use a conversion tool that supports both AIFF input and FLAC output. The exact steps depend on the application version, but the workflow is generally the same.

• 1. Open the conversion tool and add the AIFF file or files you want to convert.
• 2. Select FLAC as the output format.
• 3. If the tool shows format options, keep the sample rate and bit depth unchanged unless you specifically need to resample the audio.
• 4. Choose a destination folder that is easy to find.
• 5. Start the conversion.
• 6. Wait for the process to finish before opening or moving the new files.

If you only need one file converted occasionally, a minimal local utility may be faster to use than a full audio editor. For batches of files, choose a tool with batch processing so you do not have to repeat the same steps for every item.

Check the output

Open the destination folder and confirm that a FLAC file exists for each AIFF file you converted. Compare the file size with the original: the FLAC version is usually smaller, but the exact amount depends on the audio content. Play the converted file from beginning to end, or at least check the start, middle and end, to make sure the audio is intact.

For a more detailed check, open the original and converted files in an audio application and compare the sample rate, bit depth and channel count. If those values match, the conversion likely kept the core audio parameters unchanged.

Common problems and next steps

If a converter rejects an AIFF file, the file may use an unusual codec or have a header the tool does not support. Try opening the AIFF in another audio application first. If the application can play it, export it as a standard AIFF or WAV file and then convert that copy to FLAC.

Do not delete the original AIFF files just because the FLAC copies were created. Keep the originals until you have played the new files and confirmed that all expected audio is present. If the FLAC output is unexpectedly large or small, check whether the converter changed the sample rate, bit depth or channel layout.

For users who need a simple command-line approach, FFmpeg is a common local option on macOS. The following command converts an input AIFF file to FLAC while keeping the audio stream:

ffmpeg -i input.aiff output.flac

If the AIFF file contains a video stream or unusual metadata, you can still target the audio stream explicitly by checking the file information first and selecting the appropriate stream in the command. Avoid adding unnecessary processing unless you need to change sample rate or channel count.