Roman Numerals

Roman Numerals



The numeric system known today as Roman Numerals utilizes only seven symbols, which are added and subtracted to form any number. A superscript bar over a number multiplies it by 1,000, and two vertical lines in addition to the superscript bar multiply a number by 100,000. Thus the common symbols are:

I = 1
V = 5
X = 10
L = 50
C = 100
D = 500
M = 1,000


= 5,000
= 10,000
= 50,000
= 100,000
= 500,000
= 1,000,000


= 1,000,000
= 10,000,000
= 100,000,000
= 16,000 etc.
= 1,600,000 etc.

There was no symbol for zero
The rule is that when two figures are side by side, if the smaller is on the right, it is added to the larger, and if it is on the left, it is subtracted from the larger. So, VI = 6 and IV = 4. Exceptions to this rule are very rare.
Modern rules have also been added, and are that:

* No more than three of the same symbol can be repeated in a row, and V and L are never repeated.
* The smaller number preceeding a larger number cannot be more than two values lower than the other or be one-half of it. This leaves IV, IX, VL, XL, XC, LD, CD, and CM as the normal pairings, so we will most likely see 1999 written as MCMXCIX rather than MIM.


In reality, these rules were never followed by the Romans. To start, they used more than these seven symbols, and M was used only as an abbreviation of mille or milia, not used in combination with other symbols until the 15th century. Repetitions of numbers often exceeded the rule of three, but V and L were never repeated. Values including VIIII and even XXXXXX were common. The following table shows how much the symbols vary.

1. I


14. XIV


90. XC or LXXXX

2. II


15. XV


100. C

3. III


16. XVI


200. CC

4. IIII or IV


17. XVII


300. CCC

5. V


18. XVIII or XIIX


400. CCCC or C

6. VI or


19. XIX or XVIIII


500. D or I or

7. VII


20. XX


600. I C

8. VIII or IIX


30. XXX


700. I CC

9. VIIII or IX


40. XL or XXXX


800. I CCC

10. X


50. L


900. I CCCC

11. XI


60. LX


1,000. CI or M or or

12. XII


70. LXX


10,000. CCI or

13. XIII


80. LXXX or XXC


100,000. CCCI or







500,000. Q


*Message

On October XXXI, MCMXCIX we will attempt to rob the Last National Bank on MDLXXIX E. XXXVIIth Street in El Paso Texas. We will begin at XI o'clock in the morning. Each of the V of us will split the money. It will not be split evenly. Abel will get XXV%, Bob will get XXII%, Charlie will get XIX%, David will get XVIII%, and Eddie will get XVI%. If you need to contact me, call I-CXXIV-DLV-MMMDCLXXXIV