Convert 3G2 to FLAC — Free Online Converter

FLAC (Free Lossless Audio Codec) is the most widely supported open-source lossless audio format, capable of compressing audio to 50-60% of its uncompressed size while preserving every sample bit-for-bit. Converting 3G2 to FLAC extracts the audio from old CDMA phone recordings and stores it in a lossless, universally supported container with excellent metadata and tagging capabilities.

Unlike Apple's ALAC, FLAC is supported natively on Android, Linux, and most media players across all platforms. This makes it the ideal lossless extraction target when you are not exclusively in the Apple ecosystem and want maximum compatibility for your preserved phone audio recordings.

FLAC is the gold standard for lossless audio archival outside the Apple ecosystem. When extracting audio from 3G2 files, FLAC ensures that no additional quality loss occurs beyond what the original phone microphone and AMR codec introduced. The lossless archive can then be converted to any lossy format (MP3, AAC, OGG) in the future without compound quality degradation.

FLAC also has robust metadata support through Vorbis comments — you can tag recordings with title, artist, date, description, and custom fields. This is far superior to standalone AMR files, which have no metadata capability. For building a searchable, well-organized archive of legacy phone recordings, FLAC provides the structure you need.

FFmpeg decodes the AMR-NB or AMR-WB audio from the 3G2 container, then re-encodes it using the FLAC encoder at compression level 5 (the default balance of speed and size). Output is typically 16-bit at 44.1 kHz in a native FLAC container with Vorbis comment metadata. The video track is discarded with the -vn flag. FLAC compression level (0-8) affects only encoding speed and file size, never quality — all levels produce bit-identical decoded audio.