Roman Numerals To Numbers

Roman Numeral

Number

About Roman Numerals to Numbers Converter Online Tool:

This online Roman Numerals to Numbers Converter helps you to convert one Roman Numeral into a number (base 10). Put Roman Numeral into the first textbox, the number result will show in the second textbox.

Roman Numerals:

Roman numerals is invented by ancient Rome, it use letters from Latin ("I" for "1", "V" for "5", "X" for "10", "L" for "50", "C" for "100", "D" for "500", "M" for "1000") to represent numbers. Roman numerals is still widely used in academic paper chapter numbering system.

Step 1: Remember the Latin letters list ('I': 1, 'V': 5, 'X': 10, 'L': 50, 'C': 100, 'D': 500, 'M': 1000). Remember its order and each value.

Step 2: From left to right, subtract a letter's corresponding value if it appears before a larger letter.

Example 2.1: IV = V − I = 5 − 1 = 4

Example 2.2: XL = X − L = 50 − 10 = 40

Step 3: In other case, add a letter's corresponding value.

Example 3.1: XXXV = X + X + X + V = 10 + 10 + 10 + 5 = 35

Example 3.2: CXXIII = C + X + X + I + I + I = 100 + 10 + 10 + 1 + 1 + 1 = 123

Example 1: Convert Roman Numeral "CXLVI" to Number:

CXLVI = C + XL + V + I = 100 + (500-10) + 5 + 1 = 146

Example 2: Convert Roman Numeral "CDXCIV" to Number:

CDXCIV = CD + XC + IV = (500-100) + (100-10) + (5-1) = 494