A Primer on Watch Hour Markers

The hour markers on a dial, also known as indexes or indices, play an important role in defining the watch’s style. The same watch model can look dramatically different depending on the type of indices it has. While some take hour markers for granted, the wrong ones on a dial can actually make or break the overall look of the watch. If you’re curious about the key components of timepiece designs, below are some of the most popular hour marker styles you’ll find on luxury watch dials.

Roman Numeral Hour Markers

Roman numerals are the oldest type of numerals used on watch dials and remain popular today, particularly for classically designed timepieces.

Fun fact: If you look closely at a Roman numeral dial, you’ll see that the fourth hour is marked “IIII” rather than the correct “IV.” The use of IIII is said to bring better balance to the watch dial.

Arabic Numeral Hour Markers

Arabic numerals (a.k.a. Western Arabic numerals) are the digits most of us use in our daily lives—1, 2, 3, etc. This is different from “Eastern Arabic numerals,” which are the numbers used in Arabic script.

Some dials use Arabic numerals for all their hour markers while others only use a few, such as the 3/6/9 featured on a number of Rolex models, the most iconic probably being on the Explorer.

Breguet Numeral Hour Markers

Breguet numerals are a stylized form of Arabic numerals, named after Abraham-Louis Breguet. The theory is that these numerals were the result of A.-L. Breguet’s own handwriting.

Baton Hour Markers

Baton indexes are rectangular markers that are either painted on the dials or formed out of metal and applied onto the surface.

Dress watches typically have thinner baton markers (sometimes called stick markers) while sports watches have thicker ones—often coated in a luminous material for legibility in the dark.

Geometric Shape Hour Markers

Some watches use different shapes to mark out the hours. For example, many sports watches (particularly dive watches) have a mix of round, rectangular, square, and triangular hour markers, all filled with luminescence so that they glow in the dark.

Diamonds & Precious Gem Hour Markers

Some watches have precious gems, such as diamonds, sapphires, rubies, or emeralds, at the hours, which adds some serious sparkle to the dial. Many Rolex models feature simple diamonds as the markers, but more elaborate treatments also exist, like the Patek Philippe Nautilus pictured below, which uses emeralds to create hour marker lines on a diamond pave background.

California Dial

California dials are the names given to a very specific dial design that mixes Arabic numerals, Roman numerals, and shapes. Although Rolex invented this layout, Panerai is famous for making them today.

The Right Hour Markers on a Dial

It’s interesting to note that some watch types are partly defined by the type of indexes they have; for example, military watches and aviator watches generally rely on oversized numerals for increased legibility. What’s more, some watch brands like to stick to one type of hour marker; for instance, Cartier watches are known for their faithfulness to Roman numeral hour markers.

Sometimes, when you look at a watch, you can’t quite pinpoint why you don’t love it. Double-check the hour markers — perhaps different indices (if available on the same watch model) will change your mind entirely.