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How Does A GMT Watch Work?

How Does A GMT Watch Work

A GMT watch is a timepiece that displays both a 24-hour and 12-hour timescale. A traditional watch will rotate the hour hand in full once every 12 hours, whereas a GMT watch function is geared to rotate once every 24 hours - or half as quickly as the 12 hour hands. 

What Does GMT Stand For?

GMT stands for Greenwich Mean Time - the official time at the Royal Observatory in London, which was the basis for developing every other time zone. Greenwich Mean Time is the “zero hour” of a system that allows the wearer to know the time anywhere in the world by adding or subtracting time from it. Move west from England and you take away -1 from GMT. Move east from England and each new time zone adds + 1 to GMT. 

Originally, GMT watches were designed for pilots and frequent travellers. Nowadays, they can be enjoyed by anyone.

The Functions Of A GMT Watch

GMT watches have a number of functions. Most recently, people use GMT watches to indicate the time in another time zone. If you travel often, this is useful to ensure you are always on time. It is particularly helpful if you have connecting flights or frequent layovers. .

If synced up with local time, GMT watches can be used to easily distinguish between AM or PM. Because all 24 hours of a day are accounted for on a watch with a GMT hand, there’s no room to misinterpret whether it is AM or PM  - a handy function for those who travel through the night.

GMT watches can also have other complications like a chronograph for additional utility. Learn more about the function of a chronograph here. 

The 4 Best GMT Watches 

ROLEX 216570 Explorer II GMT 42mm Automatic Watch - White Dial

How Does A GMT Watch Work?

This remarkable GMT-equipped automatic watch from Rolex is highly functional and a real performer. A precision mechanism is housed in a sturdy stainless steel case, while the bright white dial with luminescent hands and indexes is supremely legible in both high and low-light conditions.

OMEGA Seamaster Planet Ocean 600m GMT 43.5mm Co-Axial Master Chronometer - Steel

How Does A GMT Watch Work?
It was with OMEGA’s maritime legacy in mind that the brand launched its Planet Ocean line in 2005. With its scratch-resistant sapphire crystal, this stylish OMEGA Seamaster Planet Ocean GMT chronometer features a lacquered black dial with a date window at the 3 o’clock position and a central GMT hand. 

The polished black ceramic bi-directional rotating bezel is mounted on a 43.5mm stainless steel case on a black rubber strap. The OMEGA Co-Axial calibre 8605 at the heart of this certified chronometer timepiece can be seen through the transparent case back.

This superb watch is also water resistant to 600 metres / 2000 feet, and has a helium-escape valve - the ideal luxury diving watch. 

TUDOR Black Bay GMT 41mm Automatic Watch - Red & Blue Bezel

How Does A GMT Watch Work?

Another highly functional GMT timepiece is the Tudor Black Bay, a handsome and substantial automatic watch, boldly outfitted with a popular ‘Pepsi’-style bezel - perfect for both casual and professional use. 

The watch boasts high legibility with its high-contrast dial featuring luminescent indexes on a jet black backing, excellent accuracy thanks to its precision Calibre MT5652 mechanism, and enhanced functionality with its date readout at 3 o'clock and bidirectional rotating bezel with 24-hour markers, allowing you to keep track of a secondary timezone.

Tag Heuer WAZ211A.BA0875 Formula 1 Calibre 7 GMT Automatic Watch 41mm 

How Does A GMT Watch Work?

Inspired by the excitement of the high-octane world of Formula 1, this premium watch captures the precision material design and cutting-edge glamour of the world's premier motorsport. This model sports a stainless steel construction and stark black dial, with a blue-and-black 'Batman'-style bezel.

Shop our full range of GMT watches, watch straps and watch tools and accessories on our website. 

Written by Kate, for WatchObsession.