Pocket Watch Sizing:

Here are numeric and graphic representations of the different sizes of watches you will commonly find.  Please keep in mind that the size is taken off of the dial or movement, not the case.  A 16S watch in a large case can look very similar to an 18S in a small one...

  • Numerical Watch Size Measurements

    Size Movement
    (in inches)
    (in millimeters)
    32S 2.233 56.73
    20S 1.833 46.56
    18S 1.766 44.86
    16S 1.700 43.18
    14S 1.633 41.48
    12S 1.566 39.78
    10S 1.500 38.10
    8S 1.433 36.40
    6S 1.366 34.70
    4S 1.300 33.02
    0S 1.166 29.62
    3-0S 1.100 27.94
    6-0S 1.000 25.40
    8-0S 0.933 23.71
    10-0S 0.867 22.01
    12-0S 0.800 20.32

  • Graphical Watch Size Representation

Watch Chain Weights:

While no industry standard currently exists to define the overall "Weight Class" of pocket watch chains, at PM Time Service we use the following general guideline when we are describing our chains to give an idea of what size the chain links fall into.  We use a dimensional metric for our guidelines, taking the width measurement from a typical link of the chain to determine which Weight Class the chain falls into.  In most cases, the heaviness of a chain is what one would expect from the Weight Class name, however there are numerous chain materials that are significantly lighter or heavier than their dimensional size would suggest.

In practice, any watch can be paired with any chain, however a mis-match of chain weight to watch weight can result in the chain hanging awkwardly or improperly from your person, which could increase the chance the chain may catch or snag on hazards in your environment.  In extreme cases, such as pairing a heavy 18S pocket watch with a chain in the Very Light Weight Class, the watch could overweigh the primary finding on the chain and there would be a failure of the finding to properly secure the watch to your person if the watch were to slip from a pocket or hand.  Additionally, a mis-matched pairing may create a less than attractive aesthetic result which should be taken into consideration as well.

The Watch Pairing suggestions we make should be taken as general guidelines for average-sized watches in each size range.  If you are pairing a 12S watch in an oversized hunting case (HC), it may pair well with a Heavy Weight Class chain, while an 18S in a later thin-model case might be ideally paired with a chain from the Medium Weight Class.

  • Chain Weight Classes

    Chain Weight Class Link Width Suggested Watch Pairing
    Very Light Up to 3.5mm Most ladies' slide chains will fall into this weight category and are ideally paired with all ladies' sized watches.  Pocket watch chains in this weight class are often considered "opera" style and are paired with mid-size watches, also known as "dress-size" watches.
    Light 2.2mm to 5.5mm Pocket watch chains in this weight class will be best paired with mid-size watches, also known as "dress-size" watches.
    Medium 5.0mm to 8.0mm Pocket watch chains in this weight class will best be paired with gents' watches in sizes 10S-16S.
    Heavy 7.0mm to 9.0mm Pocket watch chains in this weight class will best be paired with gents' watches in sizes 14S-18S.
    Extra Heavy 8.5mm and wider Pocket watch chains in this weight class will best be paired with gents' watches in sizes 16S and larger.
    Ribbon (not applicable) Ribbon-style chains do not conform to our standard guidelines due to the unique nature of the design.  As a rule, ribbon-style chains can be considered a unisex weight and will safely pair with both ladies and gents sized watches.

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