Abstract：Objective To measure and analyze the timing accuracy of the commonly used animation library Two.js in
online experiments, to verify whether it can meet the requirements of high-precision online experiments. Methods This
experiment used Two.js to design the flicker and raster stimuli, recorded the timing of the flicker and raster stimuli using
external measurement methods, measured the period of the visual stimuli, and obtained the timing accuracy of the visual
stimuli compared to their data results obtained under different animation engines. Results The timing accuracy of Two.js
was basically maintained within 1 ms, and could even provide sub-millisecond timing accuracy with a suitable animation engine.
Conclusion Two.js can provide millisecond timing accuracy to meet the requirements of certain online experiments for high timing
accuracy, which can provide support for network research in psychology, social sciences, and other fields.
