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Roman Numeral Converter

Use this calculator to convert Roman numerals to numbers, and to convert numbers to Roman numerals!

Roman Numeral Converter

Table of contents

Roman numerals
How to read Roman numerals
The disadvantages of using Roman numerals
You can use this Roman numeral converter to convert numbers 1 through 3,999,999 to Roman numerals. To get the regular Arabic number value, you can input a Roman numeral.
Roman numerals were a number system created in ancient Rome, where numbers are represented by letters. Roman numerals have been used to describe modern-day use, including the letters I, V, and X as well as L, C, D, and M.
You can write the maximum number in Roman numerals as MMMCMXCIX, which is 3,999. Overlines can be used in Roman numerals to represent numbers larger than 3,999. You can multiply a Roman number by 1,000 by placing an overline on it. You would use the Roman number L (50) to multiply 50,000 by Roman numerals. An overline will make it 50,000.

Roman numerals

A single line (or "I") was one unit. The "V" represented five fingers. The thumb and forefinger made the V-shape. Two hands were represented by "X". (See how two hands could touch at their points with an X?
From other symbols, larger Roman numerals were created.
M = 1,000 -- This value was originally represented by the Greek letter Ph -- It was represented sometimes as a C I and backward C like this: CIO -- which kind of looks like an "M". mille, the Latin word for one thousand, is a close coincidence.
D = 500 -- This number's symbol was originally IO -- the half of CIO.
C = 100 -- This symbol was originally theta -- Th -- but it later became a C. It also stands for centum, the Latin word that means a hundred.
L = 50 -- This was originally represented by a superimposed I and V, or the letter psi -- PS -- which initially flattened to look like an inverted TS, but eventually became an L.

How to read Roman numerals

Combining different letters to create numbers and finding the sum of these values is how you make them. The numerals are arranged from left to right. The order in which they are placed determines whether or not you add or subtract values. You add if one or more letters are placed before a letter with a higher value. You subtract if a letter is placed after a letter with a greater value. VI = 6 for V is higher than I. However, IV = 4 as I is less than V.
There are many other rules that apply to Roman numerals. You should not use the same symbol three times in succession. Subtracting amounts can only be done with powers of 10, such as I, X, or C. V or L cannot be subtracted. 95, for example, is not VC. 95 is XCV. XC equals 100 plus 10, or 90. So XC plus V or 90 plus 5 equals 95.
You cannot subtract more than one number. For example, 13 cannot be subtracted from IIXV. It is easy to see why the reasoning would be 15 minus 1 plus 1. It is actually XIII or 10 plus, according to the rule.
Also, you cannot subtract from a number that is greater than 10 times. One can subtract one from 10 (IX), but not from 100 (IC). There is no such thing as IC. Instead, you would write XCIX (XC+ IX, 90+9). A bar placed on top of a letter or string of letters increases the number's value by 1000.

The disadvantages of using Roman numerals

Roman numerals have their flaws. There is no symbol to represent zero and no way of calculating fractions. This made it more difficult to trade and prevented the development of a universally understood, complex math system. Roman numerals eventually gave way to the more flexible Arabic or Hindu numeral systems, in which numbers are read as one number in a sequence, such as 435 and four hundred thirty-five.
Ironically, Christianity was one of the first targets of persecution after the fall of the Roman Empire a thousand years later. However, it continued to use the culture’s number system even as the Roman Empire fell.
Roman numerals are used in movie titles and credits, as well as building cornerstones. They can also be used to name monarchs, popes, and sporting events like the Olympics or the Super Bowl.
Roman numerals can be used in astronomy and chemistry to indicate groups of the periodic table. These numerals can be found in the table of contents and manuscript outlines. The use of Roman numerals to break down information into a more manageable structure is possible with both upper- and lower-case Roman numbers. Roman numerals are used in music theory to indicate symbols.
These uses are more for aesthetic purposes than for functional ones. Roman numerals are used cosmetically to convey a sense that time is passing, especially in watches and clocks.

Parmis Kazemi
Article author
Parmis Kazemi
Parmis is a content creator who has a passion for writing and creating new things. She is also highly interested in tech and enjoys learning new things.

Roman Numeral Converter English
Published: Mon Apr 04 2022
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