AIFF to MP3 Converter - Convert AIFF Audio Online

This audio transcoding tool converts AIFF (Audio Interchange File Format) files into the universally compatible MP3 format using FFmpeg WebAssembly running entirely within the browser. AIFF is Apple's uncompressed, lossless audio format — the equivalent of WAV on the Mac platform. It stores raw PCM audio data at full CD quality (typically 16-bit, 44.1 kHz stereo), resulting in files roughly 10 MB per minute of audio.

The converter loads the FFmpeg engine from a CDN as a WebAssembly module, writes the uploaded AIFF file to FFmpeg's virtual filesystem, then executes the transcoding using the LAME MP3 encoder at user-selected bitrates (128, 192, 256, or 320 kbps). Since AIFF contains uncompressed PCM data, converting to MP3 involves only one generation of lossy encoding — unlike AAC-to-MP3 conversion, there is no double-lossy penalty. At 192 kbps, a typical 4-minute AIFF file (~42 MB) reduces to roughly 5–6 MB.

FFmpeg's progress events update a real-time progress bar during encoding. The built-in HTML5 audio player enables immediate preview of the converted MP3 before download. File size comparison between the original AIFF and output MP3 helps users evaluate the dramatic compression ratio. Privacy is guaranteed by the browser-local processing model — AIFF files are never transmitted to any external server.