Save Audio (MP3) (DEPRECATED)

SaveAudioMP3 is what you reach for when you don't need studio-grade audio - you need something small enough to upload, share, or slap into a video that's going to YouTube anyway. It writes your AUDIO tensor as an MP3 file to ComfyUI's output directory, and it's been wearing a (DEPRECATED) label since June 2026, when SaveAudioAdvanced absorbed it.

The node itself is simple and stable. It was added in mid-2025 as part of ComfyUI growing past FLAC-only saving, when people who wanted compressed output had to convert files by hand. The whole point was convenience: pick a bitrate, save, move on. The point remains valid - the only thing that changed is which node you should pick it from.

How it works

Same save architecture as every audio saver in core. It takes the AUDIO tensor, writes an .mp3 to output/ under your filename_prefix (default audio/ComfyUI, which lands in output/audio/), and appends a counter so reruns don't clobber each other.

The one thing that makes it different from the FLAC and Opus savers is the quality combo:

• V0 (default) - variable bitrate, ~245 kbps average. This is the quality most people actually want; it's transparent on almost everything and still small.
• 128k - a common budget choice; noticeably thinner on music, fine for speech.
• 320k - the largest, best-sounding MP3 setting. Honestly, if you need this quality you'd be better served by FLAC.

MP3 is a lossy codec, so don't use it as your master. Save FLAC for archival, then make an MP3 copy for distribution. But if you know the output is destined for a chat app or a voiceover track in a montage, MP3 at V0 is the pragmatic default.

Inputs and output

• audio (AUDIO) - the track to save.
• filename_prefix (STRING, default audio/ComfyUI) - output path prefix.
• quality (COMBO, default V0) - V0, 128k, or 320k.
• audio (AUDIO, output) - passthrough; leave it unconnected.

For the placement: this node sits at the very end of a chain. Record or load your track, trim it, level it, merge it, and only then decide on compression. If the same graph will also be asked for a lossless master, keep the FLAC save in parallel and let the MP3 branch be the "shareable" copy - two save nodes, one for each destination.

Getting it

Ships with ComfyUI core since mid-2025. No install, no models.

Common issues

Same "audio is None (source video may have no audio track)" failure as the other savers when upstream audio is missing - fix the source, not the save node. Otherwise the only real decision is quality, and V0 is a fine default for almost everything. New workflows should use SaveAudioAdvanced and pick MP3 in its format dropdown; this node is kept for backward compatibility.