Best Watches Reviews

Social Navigation

What’s the Difference Between a Chronometer and a Chronograph?

What’s the Difference Between a Chronometer and a Chronograph?

Perfect Replica

This “chronograph versus chronometer” question is an important one. Surely, the vast majority of our common perusers at MONOCHROME have the response to this inquiry. Yet, what might be said about the others, the ones who need to begin their horological venture and are coming to terms with the language? As we actually get posed this inquiry regularly, we believed that it is acceptable to explain the circumstance and to give a response to “what’s the difference between a chronometer and a chronograph?”

Chronometer versus Chronograph – Two completely extraordinary concepts

The first thing to set up while tending to the topic of the difference between a chronometer and a chronograph is that we are talking around two completely various ideas. They are not the equivalent. However, they are not inverse. The terms chronometer and chronograph are exact classifications, with exact definitions.

A chronometer checks the presentation of a watch and vouches that the watch development has been tried and constrained by an official association, under characterized rules. It has nothing to do with the elements of a watch.

A chronograph alludes to a component of a watch, something it can do, a supposed element or, in more horological language, a complication. As an update, a complication is any component in a mechanical watch past the basic presentation of hours, minutes or seconds – in this point of view, even the least complex date system is a complication.

What is a Chronometer?

To comprehend why the idea of “chronometer” was developed, we need to return to the rudiments of watchmaking. A mechanical watch, and all the more definitely its development is a piece of miniature mechanics. Like each mechanical motor depending on moving parts, it is influenced by inner and outer elements. On one hand, it is dependent upon grating, to the utilization of oils to decrease the erosion and to general mileage. Much the same as the motor of a vehicle, its presentation will, essentially, decay after some time. Contact will build, oils will debase and the moving parts will be liable to wear.

A development is additionally dependent upon outer elements, similar to dampness, heat/cold, pressing factor, attraction or gravity (the purpose for the innovation of the tourbillon… however that’s another theme). As it is a motor it won’t ever have the option to offer 100% execution, whether at a specific second or during its whole life cycle.

But what incited the development of chronometry testing? Let’s return to rudiments. What is a watch? A gadget (mechanical for this situation) that shows the time. What is time? A fixed standard, a concurred and found the middle value of estimation of the length of our days, seasons or lives – all dependent on exact computations. Hence, you have two hostile ideas battling here: a definitive accuracy of time and the natural defect of a man-made mechanical gadget. Exactness has been and is a progressing fixation for watchmakers, yet actually no human has had the option to pull off 100% precision in estimating time, constantly, with a watch. Mechanical watches are and consistently will be mistaken. In any case, “how inaccurate?” is the issue that prompted the production of the chronometer.

A chronometer, in its advanced definition, is a watch that has been tested and confirmed to fulfill certain exactness guidelines. “Chronometer” isn’t simply a name that any watch brand can print on the dial of its watches. It is an official terminology, characterized by exact principles – including the ISO 3159 norms for “Timekeeping instruments – Wrist-chronometers with spring balance oscillator“, which lays down the meaning of the term “chronometer”, depicting the classifications, the test program and the worthy least prerequisites for wrist chronometers.

Various unbiased official accreditation associations are permitted to test and authenticate watches, to give them (or not) the official “chronometer” affirmation. This incorporates, for example, the Observatoire de Besançon in France, the Glashütte Observatory in Germany or the Japan Chronometer Inspection Institute. Concerning watches created in Switzerland, just a single official association is permitted to guarantee chronometers: the COSC, or Contrôle Officiel Suisse des Chronomètres.

Only the watches that have breezed through a progression of assessments characterized by the  COSC are permitted to have the word “chronometer” imprinted on their dials. How does the COSC deal with confirm watches as chronometers? Right off the bat, developments are shipped off the COSC by brands which need their watches to be guaranteed. Then the COSC completes a progression of tests: “The checks performed by the COSC comprise of static tests acted in the lab. Every individual development/watch goes through a battery of tests explicit to every one of the four kinds, for a few sequential days, in five positions and at three unique temperatures (8°, 23° and 38°C).

Then, for 15 days (wristwatches and pocket watches), the developments go through every day tests. Consistently, including ends of the week, the instruments are estimated and reassembled. Based on the estimations, 7 disposal standards are calculated. If and just if the 7 models are met, the development/watch is guaranteed as a chronometer. The models are:

  • average day by day rate
  • mean variety in rates
  • greatest variety in rates
  • the difference between rates in even and vertical positions
  • largest variety in rates
  • variation in rate contingent upon temperature
  • rate resumption

Each of the tests is acted in 5 positions – 3 o’clock, 6 o’clock, 9 o’clock, dial on top, dial on the base. The following are the base necessities for a watch to be guaranteed chronometer:

The generally natural of the necessities (and the least complex to comprehend) is the normal every day rate. only It isn’t sufficiently adequate to make a watch a chronometer, however this reference sets up an every day deviation pace of – 4 seconds/+6 seconds as a base. This implies that lone mechanical watches with a safety buffer beneath 0,005% can be affirmed as a chronometer… You said exact, we say amazingly precise.

What is a Chronograph?

On the opposite of a chronometer, a chronograph has nothing to do with the exactness of the development. A chronograph is an extra capacity – a complication – added to the fundamental presentation (hours, minutes, seconds). Whether the watch is exact or not has nothing to do with the term chronograph. The chronograph is what might be compared to the route framework or the warmed seats in a vehicle. It’s some portion of the alternatives list, something more you can add to make your vehicle more pragmatic or more comfortable… But it won’t make it more proficient or perform better.

What is a chronograph? As per the COSC, chronographs are “instruments furnished with a system initiated by push-pieces and empowering the estimation of a brief timeframe. Such an instrument is known as a chronograph or chronoscope” or additionally a stopwatch. A chronograph is an instrument where an autonomous breadth seconds hand can be begun, halted, and got back to zero by progressive tension on the pushers (or anything that can incite the chronograph system). In current watches, it generally comprises signs for the passed minutes and hours, notwithstanding the seconds.

The term chronograph comes from the old Greek khronográphos, which means “time recording”. However, gráphō has a more exact importance, which is “writing”. Indeed, probably the soonest chronographs depended on pivoting plates covered with paper, on which a pen was in a real sense composing (or recording) the passed times. This is the idea that Nicolas Mathieu Rieussec created – and as he was the first to really commercialize this composing instrument, the name chronograph stuck. Be that as it may, he was not the designer of the stopwatch – the main chronograph was imagined by Louis Moinet in 1816, exclusively for working with galactic hardware. See beneath the Rieussec gadget (left) and the Moinet Compteur de Tierce (right).

Modern-day chronographs are standard watches that demonstrate the time just as an extra capacity to quantify brief timeframes. These watches can be perceived by the pushers on their cases (generally two of them, one situated at 2 o’clock, one situated at 4 o’clock) and their dials with 2 or 3 sub-counters. With them, and without influencing the sign of the current time, you can begin a free system to record slipped by times, stop this capacity when the occasion is done and reset the instrument to begin another planning session.

Mechanical chronographs are complex instruments that require a ton of innovative work, just as talented watchmakers to be assembled and adjusted.

Can a watch be both a Chronograph and a Chronometer?

Yes and no… To makes things understood (as per the COSC), a chronograph all alone can’t be ensured a chronometer, as the capacity of a chronograph is to quantify brief timeframes – the span of a specific occasion. As of now, there is no norm to guarantee the exactness of a chronograph alone. In the current case, “chronograph alone” implies sports instruments (like stopwatches) that just have a chronograph work, without the sign of the current time. These are not watches essentially, however straightforward time-estimating instruments.

As for watches furnished with a chronograph, they can be chronometer ensured on the off chance that they comply with the prerequisites we laid out before. In this unique situation, the chronograph is simply viewed as an extra capacity and has no effect on the tests did by the COSC. The solitary necessity is that the watch – accordingly the estimation of the current time – is acclimated to a high precision.

Various watches right now available are the two chronometers and chronographs. For example, the Rolex Daytona is a chronograph and simultaneously (as all Rolex watches) a high exactness chronometer, guaranteed by the COSC. Same goes for the Omega Speedmaster Automatic with the type 9900, the Breitling Navitimer with Caliber B01 , the  Chopard Mille Miglia  or the  Porsche Design Monobloc Actuator . In any case, a chronograph isn’t essentially a chronometer – truth be told, most chronographs aren’t chronometer-certified.


In short, a chronograph is a complication to gauge brief timeframes and a chronometer is a high-accuracy watch, affirmed by an official association. They are diverse however not adversary concepts.