Roman Numerals Converter
Convert between Roman numerals and decimal numbers easily and accurately.
Enter Your Number
Table of Contents
History and Origins of Roman Numerals
Roman numerals represent one of the oldest numeral systems still in use today. This ancient number system originated in Rome over 3,000 years ago and has an impressive history that spans millennia.
Etruscan Origins
The Roman numeral system wasn't created in isolation—it evolved from the numeral system of the Etruscans, who inhabited north-central Italy before Rome rose to power. The Etruscans used symbols that would later evolve into the Roman numerals we recognize today:
- The symbols I, V, and X derive directly from Etruscan numerals.
- The Etruscan symbol "𐌠" became the Roman "I" (1).
- The symbol "𐌡" evolved into "V" (5).
- The symbol "𐌢" transformed into "X" (10).
Evolution of the System
As Roman civilization expanded, their numeral system developed to meet growing mathematical needs:
- Early Romans used simple additive notation (III for 3, IIII for 4).
- The subtractive principle (IV for 4 instead of IIII) emerged later to simplify writing.
- Symbols for larger numbers like L (50), C (100), D (500), and M (1000) were added as commerce and administration required larger calculations.
- The symbol C (100) likely derived from the first letter of the Latin word "centum" (hundred).
- Similarly, M (1000) may relate to "mille" (thousand).
Usage Throughout History
Roman numerals remained the dominant number system in Europe long after the fall of Rome:
- They were used extensively throughout the Middle Ages for record keeping, dating, and mathematical calculations.
- Only gradually, from the 14th century onward, did Arabic numerals (1, 2, 3...) begin to replace Roman numerals in everyday use.
- The transition was slow—many European accounting books still used Roman numerals until the 17th century.
Roman numerals didn't include a symbol for zero. The concept of zero as a number came to Europe much later from Indian mathematics via Arabian scholars.
On some clock faces, you might see IIII instead of IV for the number 4. This tradition, called the "clockmaker's four," maintains visual balance with the VIII (8) on the opposite side.
Modern Usage
Despite being replaced by Arabic numerals for most mathematical purposes, Roman numerals remain relevant in modern times:
- Clock and watch faces
- Book chapter numbering
- Movie sequel titles (Rocky II, Star Wars VIII)
- Olympic Games (Games of the XXXII Olympiad)
- Super Bowl numbering
- Monarchs' names (Queen Elizabeth II)
- Copyright dates in films and television
- Cornerstones of buildings
The persistence of Roman numerals through millennia demonstrates their cultural significance and aesthetic appeal, even in our digital age.
How to Convert Roman Numerals
Roman numerals use the following symbols:
I = 1
V = 5
X = 10
L = 50
C = 100
D = 500
M = 1000
Rules for Roman Numerals:
-
1When a smaller value symbol appears before a larger value symbol, subtract the smaller value
-
2When a larger value symbol appears before a smaller value symbol, add the values
-
3Symbols can be repeated up to 3 times in a row
IV = 4 (5 - 1)
VI = 6 (5 + 1)
IX = 9 (10 - 1)
XI = 11 (10 + 1)
Common Examples
Example 1 I, II, III
I = 1
II = 2
III = 3
Example 2 IV, V, VI
IV = 4
V = 5
VI = 6
Example 3 IX, X, XI
IX = 9
X = 10
XI = 11
Example 4 XL, L, LX
XL = 40
L = 50
LX = 60