What do Chronometer and Chronograph mean? What are the differences between Chronometer and Chronograph?

What do Chronometer and Chronograph mean? What are the differences between Chronometer and Chronograph?


Chronometer is a designation given to a watch that has the highest standard of precision. The designation is given to automatic and mechanical movement watches, not those that run with quartz movement. A watch carrying the chronometer certification has passed vigorous tests demanded by the Swiss Official Chronometer Control (COSC), an  official watch testing laboratory in Switzerland.

A chronometer's mechanical movement is close to perfection, so the time it displays is almost always accurate (unlike other self-winding or automatic watches), and therefore carries a premium price over non-chronometer watches. The 15 days of rigorous tests conducted by the COSC include testing its performance under different temperatures, different positions, and even under water. The watch must lose no more than five seconds per day in order to be designated a chronometer.  Watches that have certified movements will usually be stamped with an inscription that says "Chronometer," "Certified Chronometer," or "Superlative Chronometer Officially Certified."

A chronograph designation is often confused with a chronometer one, though they are completely different. A chronograph is basically a watch with stopwatch capabilities. It displays different counters or mechanisms for measuring elapsed time. Most have two or three sub-dials, or mini-dials. Counters can register seconds, minutes and hours. This gives its owner the ability to time anything he wants.