Click anywhere to start. This is a simple tool to measure your reaction time. The average (median) reaction time is 273 milliseconds, according to the data collected so far. In addition to measuring …

4 days ago · The meaning of REACTION is the act or process or an instance of reacting. How to use reaction in a sentence.

reaction（反应）是源自拉丁语“reactio”的英语名词，兼具日常用语与专业术语属性，音标为英 [riˈækʃn]/美 [riˈækʃ (ə)n]，指对外界刺激或物质作用的应答行为。

May 25, 2026 · What are the basics of chemical reactions? A chemical reaction is a process in which one or more substances, also called reactants, are converted to one or more different substances, …

Knowing your reaction time is an important part of your life and can be used to measure your alertness, quick thinking, and overall physical performance. It can be used in a variety of ways, such as in …

Online reaction time test. Click as soon as the field turns green. Average and best time, attempts, CSV export, and built‑in self‑tests.

Reaction may refer to a process or to a response to an action, event, or exposure.

A chemical reaction is the change that happens when two or more substances are mixed with each other.

How fast are your reflexes? Take the reaction time test and find out your speed in milliseconds. Compare your score to averages by age, gender, and gamer rank.

When chemical reactions occur, the atoms are rearranged and the reaction is accompanied by an energy change as new products are generated.