Sync anything to audio.

An open file format that fingerprints audio into a stream of time cues. Any device hearing the source (via microphone or local audio) matches the fingerprints to locate itself and stay in sync in real time.

Subtitles Karaoke Haptics Generate

› status / idle

Try it

Listen · Microphone

Open this on another device. It listens via the microphone and stays in sync with whatever audio it hears — no network connection needed.

or

Open in a new window

Point the listening device roughly toward the speaker.

AFS v0.1 reference demo. Apache 2.0.

Content credits: Tears of Steel © Blender Foundation, CC-BY 3.0 · 1812 Overture by the U.S. Army Band (Public Domain) · Cannon footage: "Firing the cannon at Fort Snelling" by G. Edward Johnson, CC BY 3.0 · Silent Night performed by the U.S. Air Force Band Singing Sergeants (1990, Public Domain) · Karaoke lyrics aligned with WhisperX