Mp4a.40.2 -140- |verified| Info

Extremely old hardware (pre-2008) may struggle, but the -140- profile is considered the "safest" high-quality audio format for web streaming.

When you use tools like youtube-dl or yt-dlp to download audio from streaming platforms (e.g., YouTube, Vimeo, or custom HLS streams), you will see format codes like 140 or 141 . The format code 140 universally maps to: mp4a.40.2 -140-

Apple’s HLS standard uses variant playlists (.m3u8). You will see: Extremely old hardware (pre-2008) may struggle, but the

In many open-source media frameworks (like FFmpeg or certain builds of VLC Media Player), status codes are appended to codec identifiers during the decoding process. A value like is often parsed by users from error logs. You will see: In many open-source media frameworks

Notice: Format 140 is the for AAC. It is not as low as 48kbps (muddy) and not as high as 256kbps (overkill for most listening). At 128kbps, AAC-LC achieves near-transparent audio quality for 90% of listeners.

One such cryptic string that frequently appears in logs, stream manifests (M3U8), and codec lists is: .