Question 1

How do you use the Roman Numeral Converter?

Accepted Answer

To convert a number to a Roman numeral, enter a whole or decimal number in the first field. For large numbers, you can select Vinculum notation. To convert a Roman numeral to a number, type it in the second field. The result appears instantly.

Question 2

How do Roman numerals work?

Accepted Answer

Roman numerals work through a combination of addition and subtraction. Symbols of lesser value placed after greater ones are added (e.g., VI = 6), while a symbol of lesser value before a greater one is subtracted (e.g., IV = 4). A bar over a numeral (Vinculum) multiplies its value by 1,000.

Question 3

How did the Romans write fractions?

Accepted Answer

The Romans based their fractions on a system of twelfths called unciae. A dot (·) represented 1/12, and the symbol 'S' represented a half (6/12).

Question 4

Can this tool convert decimal numbers to Roman numerals?

Accepted Answer

Yes, the converter can handle decimal numbers. It translates the fractional part into the nearest twelfth (uncia), following the Roman system for fractions.

Question 5

What is Vinculum notation and when should I use it?

Accepted Answer

Vinculum notation is a method for writing large numbers where a bar (overline) is placed above a Roman numeral to multiply its value by 1,000. You should use the Vinculum option for converting integers larger than 3,999.

Question 6

What are the rules for subtraction in Roman numerals?

Accepted Answer

The subtractive principle has specific rules: 1) Only powers of ten (I, X, C) can be subtracted. 2) You can only subtract a single letter from the next two higher values (e.g., I from V and X; X from L and C; C from D and M). 3) You cannot subtract a letter from another letter that is more than 10 times greater (e.g., IC for 99 is incorrect; it should be XCIX).

Question 7

Why is there no zero in Roman numerals?

Accepted Answer

The Roman numeral system was developed for counting and trade, and it lacked a character for zero because there was no need to represent 'nothing'. The concept of zero as a number was introduced to Europe much later.

Question 8

Why do some clocks use IIII instead of IV for the number four?

Accepted Answer

This is known as the 'watchmaker's four.' It's a tradition in clockmaking done primarily for aesthetic reasons. Using IIII provides better visual symmetry and balance with the VIII (8) on the opposite side of the clock face.

Question 9

Are Roman numerals still used today?

Accepted Answer

Yes, Roman numerals are still used in various contexts today, such as for the Super Bowl, in the names of monarchs and popes (e.g., Queen Elizabeth II), for chapter headings in books, in outlines, and on building cornerstones to denote the year of construction.

Question 10

What is the largest number this converter can handle?

Accepted Answer

Using standard notation, the converter supports numbers up to 3,999. With Vinculum notation enabled, it can convert integers up to 3,999,999.

Question 11

Does this converter support Apostrophus notation?

Accepted Answer

No, due to its complexity and rarity in modern use, this converter does not support the ancient Apostrophus system for writing large numbers.

Symbol	Value
I	1
V	5
X	10
L	50
C	100
D	500
M	1000

Symbol	Value	Symbol	Value
·	1/12	S·	7/12
··	2/12 (1/6)	S··	8/12 (2/3)
···	3/12 (1/4)	S···	9/12 (3/4)
····	4/12 (1/3)	S····	10/12 (5/6)
·····	5/12	S·····	11/12
S	6/12 (1/2)	-	-

Roman Numeral Converter

How to Use This Converter

How Roman Numerals Work

Character Values (Integers)

Key Rules for Integers

Fractions (Unciae)

A Note on Apostrophus Notation