What is the difference between a chronometer and a chronograph?
While they both share the same root word chrono, a chronometer and chronograph are two completely different types of watches. The “chrono” part comes from the word chronometry: the science of measuring time. Let’s dig in a little more to learn the differences between the two…
What is a chronometer watch?
A chronometer is generally referred to as a watch that keeps time within a certain specification of timekeeping, usually within a range of +/- a few seconds per day. There are organizations that certify movements to be within a specific range that they deem acceptable for passing certification. The most common reference to this is COSC which (sometimes there is also confusion about the differences between a chronometer and COSC).
What is a chronograph watch?
A chronograph watch is a timepiece that has a stopwatch function. There are different ways of executing this complication in a watch, but the most common is by having two pushers on the case: one for starting and stopping the stopwatch and one for resetting it back to zero. Many multi-functional watches like G-Shocks have a chronograph function as well.
Here is a video of a chronograph function in action:
Quartz Chronometers – Although you will mostly see the word Chronometer on mechanical watch dials, quartz watches can also be certified as chronometers. In fact, even the cheapest $3 quartz calibers can technically be considered chronometers based on the highly accurate nature of quartz movements. So when you see other articles online claiming that the chronometer designation is only given to mechanical watches, they are wrong. (Example coming soon.)
Other Chronometers – You may also see the word used in reference to a marine chronometer. These devices were found on ships to help navigate the course of ocean travel. While there are some modern reissue marine chronometers available today, the tools used on vessels were typically encased in a wooden box with the mechanical clock attached to a gimbal, which allowed the timekeeping mechanism to remain in the same position despite the ship being rocked around by waves. By always keeping the clock in the same position, it resulted in more accurate timekeeping, which results in more accurate navigating. (Example coming soon.)
Now that we have a better understanding about the differences between these two watch terms, it’s fun to acknowledge that a chronometer can be a chronograph and a chronograph can be a chronometer!