The ROMAN function converts Arabic numerals into Roman numerals in a text format. It can return the classic Roman numeral style or more concise versions of each number.
Contents:
Example - Converting Numbers into Roman Numerals
Syntax
= ROMAN(number, [form])Number = a number between 1 and 3999 that will be converted
[form] = a number specifying which condensed Roman numeral form is to be used. See the table below for more information
Explanation
The ROMAN function is part of the "Math & Trigonometry" group of functions within Excel.
What are Arabic and Roman Numerals?
Arabic numerals are what you would think of as standard numbers used widely across the world. They are the ten numerical digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.
They are called Arabic numerals as they were introduced into Europe originally by Arabic speakers from Spain and North Africa.
Roman numerals on the other hand, originated from ancient Rome, and are comprised of seven basic symbols.
These seven symbols, as seen on the left, are combined in various ways to represent different numbers.
A symbol placed before another symbol of equal or greater value subtracts their value together. And a symbol placed after, is added.
For example, V represents 5. If we include the Roman version of 1 or I before V to get IV, we get the number 4. Conversely, VI would be 6, as the I comes after the larger symbol and is added.
This process is repeated for all symbols in a given Roman numeral.
What Are the Different Forms That Can be Used?
Within the ROMAN function, by using the optional form argument, the Roman numeral returned can be adjusted to be more or less concise.
There are 7 inputs for form that may be used to return different configurations of Roman numerals. The numbers will always be read as the same number, but the level of conciseness will change.
Some numbers can be written in a more condensed way and some may not. For instance, the typical way to write 499 would be CDXCIX where CD = 400, XC = 90, and IX = 9, totaling 499. But, 499 could also be written as ID, or one less than 500 = 499.
Important Notes
- This function will only work on numbers up to 3999. Any number larger than that will return a #VALUE! error
- If the number is negative a #VALUE! error will be returned
- If the input value is anything other than a number, a #VALUE! error will also be returned
- Decimal values will be ignored
To convert Roman Numerals into Arabic Numerals, use the ARABIC function.
Examples
How to Convert Numbers into Roman Numerals
Here is an example of using the ROMAN formula to convert standard Arabic numbers into Roman Numerals.
In each formula, the Arabic numerals are referenced as the number argument. In the last two rows are examples of the form argument being used.
The default (or 0) which the other rows are using the classic Roman numeral styling, while the very last row is using form 4, the most simplified version possible. This can be seen by comparing the last two rows which are converting 3,999.
In row 8, using the standard styling of 0, 3,999 is converted to MMMCMXCIX. If we instead use form 4, then the converted number is shortened to MMMIM.
= ROMAN(B3, 4)