How Time Works on Planet Earth
A visual, scientific encyclopedia exploring the mechanics of atomic clocks, international time zones, and circadian biology.
Coordinated Universal Time (UTC): The World's Clock Anchor
Coordinated Universal Time (UTC) is the primary time standard by which the world regulates clocks and time. It is not a time zone itself, but an agreed-upon baseline from which all 24+ world time zones are calculated as positive or negative offsets (e.g. UTC+1 for Paris, UTC-5 for New York).
Calculated by averaging hundreds of primary cesium and rubidium atomic clocks situated in national metrology institutes across 60+ countries.
Maintained by the International Bureau of Weights and Measures (BIPM) in Sèvres, France to ensure satellite navigation, internet routing, and aviation remain synchronized.
Explore Global Time & Related Directories
Quick access to international capitals, timezone offsets, chronometry tools, and horology guides