Why is 2026 in the 21st century, not the 20th?

Centuries are conventionally counted starting from year 1, so the 1st century ran from year 1-100, meaning the 21st century runs from 2001-2100, which includes 2026.

Century Calculator

Determine which century a given year falls into, accounting for the fact that centuries are conventionally numbered starting from year 1, not year 0.

Inputs

Results

Century: 21

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Formula

Century = ceil(Year / 100)

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Calendar Curiosities: Quarters, Zodiac Signs, Seasons, and Centuries

How calendar quarters, zodiac signs, meteorological seasons, centuries, and the days in a given month are each determined.

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