Roman Numerals Conversion
A number in Roman Numerals is a collection of the symbols (or letters/characters) C, D, I, L, M, V, X has written in a specific order (e.g. M’sM’s first, followed by D’sD’s, C’sC’s etc.). Generally, a subtractive notation is used in some cases to avoid four characters being replicated in sequences, such as IIII or XXXX, as shown below.
- If “I” is placed before V or X, it represents one less, then four is IV (one less than 5), and 9 is IX (one less than 10)
- If “X” is placed before L or C, it represents ten less, then 40 is XL (10 less than 50), and 90 is XC (10 less than 100)
- If “C” is placed before D or M, it represents a hundred less, then 400 is CD (100 less than 500), and 900 is CM (100 less than 1000)
Roman Numerals Calculation
The below table shows the calculations to get the number for a given roman numeral.
Roman Numeral |
Calculation to get the number |
Roman Numeral |
Calculation to get the number |
I |
1 = 1 |
XXXVI |
10 + 10 + 10 + 5 + 1 = 36 |
II |
1 + 1 = 2 |
XXXVII |
10 + 10 + 10 + 5 + 1 + 1 = 37 |
III |
1 + 1 + 1 = 3 |
XXXVIII |
10 + 10 + 10 + 5 + 1 + 1 + 1 = 38 |
IV |
5 – 1 = 4 |
XXXIX |
10 + 10 + 10 – 1 + 10 = 39 |
V |
5 |
XL |
-10 + 50 = 40 |
VI |
5 + 1 = 6 |
XLI |
-10 + 50 + 1 = 41 |
VII |
5 + 1 + 1 = 7 |
XLII |
-10 + 50 + 1 + 1 = 42 |
VIII |
5 + 1 + 1 + 1 = 8 |
XLIII |
-10 + 50 + 1 + 1 + 1 = 43 |
IX |
10 – 1 = 9 |
XLIV |
-10 + 50 – 1 + 5 = 44 |
X |
10 |
XLV |
-10 + 50 + 5 = 45 |
XI |
10 + 1 = 11 |
XLVI |
-10 + 50 + 5 + 1 = 46 |
XII |
10 + 1 + 1 = 12 |
XLVII |
-10 + 50 + 5 + 5 + 1 = 47 |
XIII |
10 + 1 + 1 + 1 = 13 |
XLVIII |
-10 + 50 + 5 + 1 + 1 + 1 = 48 |
XIV |
10 – 1 + 5 = 14 |
XLIX |
-10 + 50 – 1 + 10 = 49 |
XV |
10 + 5 = 15 |
L |
50 |
XVI |
10 + 5 + 1 = 16 |
LX |
50 + 10 = 60 |
XVII |
10 + 5 + 1 + 1 = 17 |
LXX |
50 + 10 + 10 = 70 |
XVIII |
10 + 5 + 1 + 1 + 1 = 18 |
LXXX |
50 + 10 + 10 + 10 = 80 |
XIX |
10 – 1 + 10 = 19 |
XC |
-10 + 100 = 90 |
XX |
10 + 10 = 20 |
C |
100 |
XXI |
10 + 10 + 1 = 21 |
CC |
100 + 100 = 200 |
XXII |
10 + 10 + 1 + 1 = 22 |
CCC |
100 + 100 + 100 = 300 |
XXIII |
10 + 10 + 1 + 1 + 1 = 23 |
CD |
-100 + 500 = 400 |
XXIV |
10 + 10 – 1 + 5 = 24 |
D |
500 |
XXV |
10 + 10 + 5 = 25 |
DC |
500 + 100 = 600 |
XXVI |
10 + 10 + 5 + 1 = 26 |
DCC |
500 + 100 + 100 = 700 |
XXVII |
10 + 10 + 5 + 1 + 1 = 27 |
DCCC |
500 + 100 + 100 + 100 = 800 |
XXVIII |
10 + 10 + 5 + 1 + 1 + 1 = 28 |
CM |
-100 + 1000 = 900 |
XXIX |
10 + 10 – 1 + 10 = 29 |
M |
1000 |
XXX |
10 + 10 + 10 = 30 |
[latex]\overline{V}[/latex] |
5000 |
XXXI |
10 + 10 + 10 + 1 = 31 |
[latex]\overline{X}[/latex] |
10000 |
XXXII |
10 + 10 + 10 + 1 + 1 = 32 |
[latex]\overline{L}[/latex] |
50000 |
XXXIII |
10 + 10 + 10 + 1 + 1 + 1 = 33 |
[latex]\overline{C}[/latex] |
100000 |
XXXIV |
10 + 10 + 10 – 1 + 5 = 34 |
[latex]\overline{D}[/latex] |
500000 |
XXXV |
10 + 10 + 10 + 5 = 35 |
[latex]\overline{M}[/latex] |
1000000 |
Date In Roman Numerals Conversion
We can represent the date of the day using roman numerals. Let us take the format to represent the date as MM-DD-YYYY (Month-Day-Year). For example, 12-20-2019 is written as XII-XX-MMXIX.
We can easily write the years of the 21st century as shown below.
2001 = MMI
2002 = MMII
2003 = MMIII
2004 = MMIV
2005 = MMV
2006 = MMVI
2007 = MMVII
2008 = MMVIII
2009 = MMIX
2010 = MMX and so on
Numbers To Roman Numerals Conversion
To convert numbers into roman numerals, we first need to split the given number based on the numerical value or place value of the digits in the number. It is very easy to convert any numbers into a roman form and conversely, any roman form into a number. The below example helps in better understanding of the above conversion.
Roman Numerals Example
Example 1:
Convert the number 1786 into the form of a roman numeral.
Solution:
First we need to split 1786 into thousands, hundreds, tens and units.
1786 = 1000 + 700 + 80 + 6
1000 = M
700 = DCC
80 = LXXX
6 = VI
Therefore, 1786 = MDCCLXXXVI
Example 2:
Convert the number 9143 into the roman numeral.
Solution:
Let us split 9143 into thousands, hundreds, tens and units.
9143 = 9000 + 100 + 40 + 3
9000 = [latex]\overline{IX}[/latex]
100 = C
40 = XL
3 = III
Therefore,
9143 = [latex]\overline{IX}[/latex] CXLIII