Using the Roman numerals and alphabet converter
The calculator will convert positive integer less than 5000 between Roman numerals and alphabet. The largest number you can enter is 4999, or MMMMCMXCIX in Roman numerals format.
About Roman numerals
Roman Numerals are based on seven symbols
 I = 1
 V = 5
 X = 10
 L = 50
 C = 100
 D = 500
 M = 1,000
There are several rules for writing Roman numerals.
 Repeating a numeral up to three times represents addition of the number. For example, XXX represents X + X + X = 30. Only I, X, C, and M can be repeated; V, L, and D cannot be repeated.
 Writing numerals that decrease from left to right represents addition of the numbers. For example, LX represents 50 + 10 = 60 and XVI represents 10 + 5 + 1 = 16.
 TWriting a smaller numeral to the left of a larger numeral represents subtraction. For example, IV represents 5  1 = 4 and IX represents 10  1 = 9. but the only pairs of numerals that use this subtraction rule are:
 IV = 5  1
 IX = 10  1
 XL = 50  10
 XC = 100  10
 CD = 500  100
 CM = 1000  10
Here is an example about repeating and subtraction rules:
Let's convert a Roman numerals to alphabet number.
MMCMXCIX
= M + M + (M  C) + (C  X) + (X  I)
= 1000 + 1000 + (1000  100) + (100  10) + (10  1)
= 2999
Most used Roman numerals from one to a thousand
Roman Numerals  Arabic Numerals 


uppercase  lowercase  
I  i  1 
II  ii  2 
III  iii  3 
IV  iv  4 
V  v  5 
VI  vi  6 
VII  vii  7 
VIII  viii  8 
IX  ix  9 
X  x  10 
XI  xi  11 
XII  xii  12 
XIII  xiii  13 
XIV  xiv  14 
XV  xv  15 
XVI  xvi  16 
XVII  xvii  17 
XVIII  xviii  18 
XIX  xix  19 
XX  xx  20 
XXI  xxi  21 
XXII  xxii  22 
XXIII  xxiii  23 
XXX  xxx  30 
XL  xl  40 
L  l  50 
LX  lx  60 
LXX  lxx  70 
LXXX  lxxx  80 
XC  xc  90 
C  c  100 
CC  cc  200 
CCC  ccc  300 
CD  cd  400 
D  d  500 
M  m  1000 