Roman Numerals

Roman Numerals for the Pharmacy Technician

Roman numerals originated in Ancient Rome and were the primary system until the Late Middle Ages. Although there are some variants of the symbols used for this numbering system, in the pharmacy there are 7 symbols to which you will see most often: I, V, X, L, C, D, M.


When deciphering Roman numerals there are 4 essential rules to remember:


  1. When one or more numerals are placed after a numeral of greater value you add. Example – MXV (1,000 + 10 + 5 = 1015)
  2. When a numeral is placed before a numeral of greater value you subtract. Example – IV = 4, IX = 9
  3. A repeated numeral (never more than 3 times) is added that many times. Example – CC = 200
  4. Always look for and perform subtraction first in long strings of numerals. Example – LXIV= LX + (IV)

Chart of Common Roman numerals:

Roman NumeralValueRoman NumeralValueRoman NumeralValue
I1VI6XX20
II2VII7L50
III3VIII8C100
IV4IX9D500
V5X10M1000