What is timer.js?

timer.js solves a surprisingly specific problem: when you're building something in the browser that needs to stay perfectly in sync with an audio file, the browser's built-in audio timing can let you down. Instead of relying on the audio element's clock, this library gives you a lightweight JavaScript timer that tracks elapsed time independently, so your animations and visual effects stay locked to the music. The idea is simple but clever. You tell the timer how long your audio track is, say, 40 seconds, and then call play() on both the audio element and the timer at the same time. From that point on, instead of reading the current playback position from the audio element itself, you read it from the timer. This sidesteps issues where the audio element's time reporting can drift, stutter, or become unreliable, particularly in longer or more complex browser-based projects. The library is clearly designed for people building audio-driven visual experiences in the browser, think music visualizers, interactive art pieces, or rhythm-based web animations where visuals need to match the beat. The example code shows an animation loop where an object's position is tied directly to the elapsed time, which is a pattern common in creative coding and projects built with libraries like Three.js (notably, the author is also the creator of Three.js). What stands out is how minimal this solution is. Rather than building a full-featured audio synchronization library, it does one thing: provides a reliable time tracker that mirrors what an audio element should be doing. The README doesn't go into detail about edge cases, browser compatibility, or what specific audio timing problems it works around, but the existence of the project suggests those problems are real enough that someone who builds browser-based 3D graphics for a living felt the need to create his own fix.