Roman Numerals: Conversion, Meaning & Origins (2024)

Roman Numerals: Conversion, Meaning & Origins (1)

Roman numerals originated, as the name might suggest, in ancient Rome. There are seven basic symbols: I, V, X, L, C, D and M. The first usage of the symbols began showing up between 900 and 800 B.C.

The numerals developed out of a need for a common method of counting, essential to communications and trade. Counting on one's fingers got out of hand, so to speak, when you reached 10. So, a counting system was devised based on a person's hand.

Meaning of Roman numerals

A single line, or "I," referred to one unit or finger; the "V" represented five fingers, specifically, the V-shape made by the thumb and forefinger. "X" equaled two hands. (See how an X could be two Vs touching at their points?)

Larger Roman numerals developed from other symbols.

M = 1,000 — Originally, the Greek letter phi — Φ — represented this value. It was sometimes represented as a C, I and backwards C, like this: CIƆ — which sort of looks like an M. It's only a coincidence that mille is the Latin word for a thousand.

D = 500 — The symbol for this number was originally IƆ — half of CIƆ.

C = 100 — The original symbol was probably theta — Θ — and later became a C. It only coincidentally also stands for centum, the Latin word for a hundred.

L = 50 — This value was originally represented by a superimposed V and I, or by the letter psi — Ψ — which flattened out to look like an inverted T, and then eventually came to resemble an L.

How to read Roman numerals

Numbers are formed by combining various letters and finding the sum of those values. The numerals are placed from left to right, and the order of the numerals determines whether you add or subtract the values. If one or more letters are placed after a letter of greater value, you add. If a letter is placed before a letter of greater value, you subtract. For example, VI = 6 because V is higher than I. But IV = 4 because I is lower than V.

There are a number of other rules related to Roman numerals. For example, do not use the same symbol more than three times in a row. When it comes to subtracting amounts, only powers of 10 are subtracted, like I, X, or C, but not V or L. For example, 95 is not VC. 95 is XCV. XC equals 100 minus 10, or 90, so XC plus V, or 90 plus 5, equals 95.

Also, only one number can be subtracted from another. For example, 13 is not IIXV. It's easy to see how the reasoning would be: 15 minus 1 minus 1. But following the rule, it instead is XIII, or 10 plus 3.

You also cannot subtract a number from one that is more than 10 times greater. You can subtract 1 from 10 (IX) but you cannot subtract 1 from 100; there is no such number as IC. You would instead write XCIX (XC + IX, or 90+9). For larger numbers in the thousands, a bar placed on top of the letter or string of letters multiplies the numeral's value by 1,000: .

Disadvantages of using Roman numerals

Roman numerals are not without flaws. For example, there is no symbol for zero, and there is no way to calculate fractions. This hindered the ability to develop a universally understood, sophisticated math system, and made trading more difficult. Eventually, Roman numerals gave way to the more versatile Arabic or Hindu numeral system, where numbers are read as a single number in sequence, like 435 as four hundred thirty-five.

As the Roman Empire collapsed a thousand years later, Christianity (ironically one of Rome's earliest targets for persecution), continued to use the culture's number system.

Today, Roman numerals appear in building cornerstones and movie credits and titles. They are also used in names of monarchs, popes, ships and sporting events, like the Olympics and the Super Bowl.

Roman numerals are used in astronomy to designate moons and in chemistry to denote groups of the Periodic Table. They can be seen in tables of contents and in manuscript outlines, as upper- and lower-case Roman numerals break information into an easily organized structure. Music theory employs Roman numerals in notation symbols.

These uses are more due to aesthetic reasons than functional purposes. Cosmetically, Roman numerals convey a sense of history and timelessness, which is especially true in clocks and watches.


  • Who Invented Zero?
  • What is Pi?
  • Cool Math Games

Sign up for the Live Science daily newsletter now

Get the world’s most fascinating discoveries delivered straight to your inbox.

Elaine J. Hom

Live Science Contributor

More about romans

2,000-year-old funerary urn found in Spain contains the world's oldest known liquid wine2,000-year-old Roman military sandal with nails for traction found in Germany


'This is what drives the migraine headache': Scientists uncover 'missing link' in why some migraines happen
See more latest►

Most Popular
How does Tylenol work?
Why is it called 'morning sickness' if it can happen any time of day?
Why is snot sticky?
What causes bruising?
Why do wrinkles form?
Do ears and noses get bigger with age?
Why do lips get so chapped in winter?
Can drinking alcohol really cause hiccups?
Why is it safe to eat moldy cheese?
What is frankincense?
Why is pink eye so contagious?
Roman Numerals: Conversion, Meaning & Origins (2024)


Roman Numerals: Conversion, Meaning & Origins? ›

Roman numerals are symbols that are used to stand for numbers. This number system was based on the ancient Roman system and was replaced by the Hindu-Arabic numeral system. The symbols are I, V, X, L, C, D, and M, standing respectively for 1, 5, 10, 50, 100, 500, and 1,000.

What are Roman numerals and their origins? ›

Roman numerals are a numeral system that originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. Numbers are written with combinations of letters from the Latin alphabet, each letter with a fixed integer value.

What does i, ii, iii, iv mean? ›

In roman numerals, alphabets are used to represent the fixed positive numbers. These roman numerals are I, II, III, IV, V, VI, VII, VIII, IX, and X represent 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 respectively. After 10, the roman numerals are followed by XI for 11, XII for 12, XII for 13, … till XX for 20.

Why did we switch from Roman numerals to numbers? ›

The Roman system was fine for recording amounts of things, but not so useful for manipulating those amounts. The abacus — or counting frame — was useful, but limited. And for more complex calculations, Roman numerals were hopeless. This put serious limits on trade, commerce, and especially science.

What each Roman numeral stands for? ›

The Roman numeral system uses only seven symbols: I, V, X, L, C, D, and M. I represents the number 1, V represents 5, X is 10, L is 50, C is 100, D is 500, and M is 1,000. Different arrangements of these seven symbols represent different numbers. The numbers 1–10 are: 1 = I.

Who invented the number 1 to 9? ›

We all know 0 was invented by Aryabhatt. And as far as the invention of digits 1-9 is concerned, these are believed to be invented in Arab. These digits are also known as Arabic Numerals. The first positional numerical system was developed in Babylon in the 2nd millennium BC.

What is XX in Roman numerals? ›

20 in Roman Numerals is represented by XX. The expanded form to convert 20 in Roman Numerals can be written as 20 = 10 + 10.

What is z in Roman numerals? ›

Z, Symbol. the 26th in order or in a series, or, when I is omitted, the 25th. (sometimes l.c.) the medieval Roman numeral for 2000. Cf. Roman numerals.

What is XX in math? ›

We know that in roman numerals, we write 10 as X. Therefore, 20 in roman numerals is written as XX = 20.

Why do we use Arabic numerals instead of Roman numerals? ›

Arabic numeral have a symbol for every digit in base ten. Roman numeral are also in base ten (sort of) but they only have 3 symbols between 1 and 10, I, V, and X. So, adding columns of numbers becomes difficult and long division becomes impossible using Roman numerals.

What does m mean in Roman numerals? ›

here are the commonly used Roman numerals: I = 1. L = 50 M = 1000. V = 5. C = 100.

What does v mean in Roman numerals? ›

Roman numerals. Letters of the alphabet used in ancient Rome to represent numbers: I = 1; V = 5; X = 10; L = 50; C = 100; D = 500; M = 1000.

Which Roman numeral is never repeated? ›

While writing a Roman numeral, only the numerals I, X, C and M can be repeated. V, L and D cannot be repeated.

Which basic Roman numeral can never be subtracted? ›

What are the Roman numerals that can never be subtracted? Answer. The symbols V, L and D are not written to the left of a symbol that has greater value. This means that V, L and D are never subtracted.

What is the logic of Roman numerals? ›

Rule #1: When reading Roman Numerals, the value of the number is added from left to right if the left numeral is greater than the right numeral. Rule #2: If the left numeral is smaller than the right numeral, subtract the value of the left value from the right numeral.

Why did the Romans create Roman numerals? ›

Roman numerals were likely developed as a result of a need for a common method of counting in order to better conduct trade.

Where did numerals originate from? ›

We have a record of early numeral systems from Egypt (5400 years ago), China (3600 years ago), and Elam in Mesopotamia (over 3000 years ago). The Sumerians and Babylonians in Ancient Mesopotamia used a sexagesimal system (base 60).

What does C stand for in Roman numerals? ›

here are the commonly used Roman numerals: I = 1. L = 50 M = 1000. V = 5. C = 100.

Why is 3999 the highest Roman numeral? ›

The highest number that can be expressed in pure Roman numeral form is 3,999 which is written as MMMCMXCIX. This is because the number 4,000 would have to be written as MMMM, which goes against the principle of not having four consecutive letters of the same type together.


Top Articles
Latest Posts
Article information

Author: Madonna Wisozk

Last Updated:

Views: 5601

Rating: 4.8 / 5 (68 voted)

Reviews: 91% of readers found this page helpful

Author information

Name: Madonna Wisozk

Birthday: 2001-02-23

Address: 656 Gerhold Summit, Sidneyberg, FL 78179-2512

Phone: +6742282696652

Job: Customer Banking Liaison

Hobby: Flower arranging, Yo-yoing, Tai chi, Rowing, Macrame, Urban exploration, Knife making

Introduction: My name is Madonna Wisozk, I am a attractive, healthy, thoughtful, faithful, open, vivacious, zany person who loves writing and wants to share my knowledge and understanding with you.