21st Century in Roman Numerals
The 21st Century, written as XXI in Roman numerals, spans from 2001 to 2100. It defines the age of technology, connectivity, and innovation, where digital evolution, artificial intelligence, and globalization continue to transform how people live, work, and communicate worldwide.
How do you convert the 21st Century to Roman Numerals?
Add I (1) after XX (20) to form XXI.
| Place Value | Number | Roman Numeral |
|---|---|---|
| Tens | 20 | XX |
| Ones | 1 | I |
| Total | 21 | XXI |
XX + I = XXI, the correct Roman numeral for 21.
How is the 21st Century written?
Use uppercase Roman numerals — 'XXI Century'.
Decades in the 21st Century
The XXI Century (21st) includes these decades:
Years in the 21st Century
2001–2100.
Dates in the 21st Century
Starts January 1, 2001, ends December 31, 2100.
Frequently Asked Questions
What is the 21st Century in Roman numerals?
XXI.
How is 21 formed?
20 + 1 = XXI.
What years belong to it?
2001–2100.
What comes before XXI?
XX Century.
What comes after XXI?
Future centuries will continue as XXII, XXIII, etc.
Why is the 21st Century remarkable?
It’s the digital and AI-driven era of global transformation.
How is XXI written?
XX (20) plus I (1) — XXI.
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