Roman Numerals Converter

Convert between Roman numerals and decimal numbers easily and accurately.

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Enter a decimal number (1-3999)

Enter a Roman numeral (I-MMMCMXCIX)

Table of Contents

1 How to Convert Roman Numerals
2 Common Examples
Guide

How to Convert Roman Numerals

Roman numerals use the following symbols:

I = 1

V = 5

X = 10

L = 50

C = 100

D = 500

M = 1000

Rules for Roman Numerals:

  1. 1
    When a smaller value symbol appears before a larger value symbol, subtract the smaller value
  2. 2
    When a larger value symbol appears before a smaller value symbol, add the values
  3. 3
    Symbols can be repeated up to 3 times in a row
Examples:

IV = 4 (5 - 1)

VI = 6 (5 + 1)

IX = 9 (10 - 1)

XI = 11 (10 + 1)

Examples

Common Examples

Example 1 I, II, III

I = 1

II = 2

III = 3

Example 2 IV, V, VI

IV = 4

V = 5

VI = 6

Example 3 IX, X, XI

IX = 9

X = 10

XI = 11

Example 4 XL, L, LX

XL = 40

L = 50

LX = 60

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Decimal To Hex Roman Numerals Percent To Decimal Fraction To Decimal Decimal To Binary

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