Free online AIFF to W64 converter

Source format: AIFF

AIFF (Audio Interchange File Format) is a classic uncompressed audio format developed by Apple. It is widely used in professional audio production, especially on macOS, for storing high-quality recordings, edited masters, and exchange files between audio applications. AIFF typically contains PCM audio, which preserves full fidelity but can produce large files.

Target format: W64

W64 is the Wave64 audio container, an extended version of WAV designed by Sony to overcome the 4 GB size limit of standard RIFF/WAV files. It is used in broadcasting, post-production, and archival workflows where very large uncompressed audio files are common. W64 supports long recordings and high-resolution audio while remaining broadly compatible with professional tools that understand the format.

How to perform the conversion

The most reliable way to convert AIFF to W64 is with a desktop audio editor or command-line tool that supports both formats. A common choice is FFmpeg, which is free, widely available, and handles uncompressed audio well.

1. Install FFmpeg on your computer if it is not already available.
2. Open a terminal or command prompt in the folder containing your AIFF file.
3. Run a command such as ffmpeg -i input.aiff -c:a pcm_s24le output.w64.
4. If you want to preserve the original sample format as closely as possible, you can also use ffmpeg -i input.aiff -c:a copy output.w64 when the source audio encoding is compatible with the W64 container.
5. Verify the result by opening the W64 file in your audio editor or player.

If you prefer a graphical workflow, some professional editors such as Adobe Audition, Sound Forge, or other advanced audio tools may export to Wave64 through File → Save As or File → Export, depending on the application. You can also convert the file on 101convert.com for free, without installing any software.

Notes on quality, compatibility, or limitations

AIFF to W64 is usually a lossless conversion when both formats store uncompressed PCM audio. That means the audio quality should remain unchanged. The main differences are in the container format and file-size handling, not the sound itself.

Keep in mind that W64 support is more limited than standard WAV or AIFF support. Some consumer players and editors may not open W64 files, while professional audio software usually does. If compatibility with general-purpose software is important, WAV may be a safer choice unless the file is too large for standard WAV.

Also note that if the source AIFF contains unusual metadata, compressed audio, or nonstandard channel layouts, not every converter will preserve every detail perfectly. For archival or production use, it is a good idea to test the converted file in the exact software or hardware where it will be used.