Roman Numeral Converter

Convert numbers to Roman numerals and vice versa. Free, works in your browser, and no registration required.

Number to Roman

Roman to Number

Roman Numeral Reference

I
1
V
5
X
10
L
50
C
100
D
500
M
1000
IV
4
IX
9
XL
40
XC
90
CD
400
CM
900

Roman Numeral Rules

  • Roman numerals are formed by combining letters and adding their values
  • When a smaller numeral appears before a larger one, it is subtracted (e.g., IV = 4)
  • No more than three of the same numeral can appear in a row (e.g., III = 3, but IIII is not used)
  • The subtractive notation is only used with specific pairs (IV, IX, XL, XC, CD, CM)
  • Roman numerals typically range from 1 to 3999

How to use Roman Numeral Converter

  1. Select your conversion type (Number to Roman or Roman to Number).
  2. Enter your number or Roman numeral in the input field.
  3. Click the 'Convert' button to see the result instantly.

Features

  • Supports conversion in both directions (numbers to Roman numerals and vice versa).
  • Handles a wide range of numbers, from 1 to 3,999 and beyond.
  • Performs conversions instantly with a single click.
  • Provides accurate results following standard Roman numeral rules.
  • Works seamlessly on any device with a web browser.

Who Is This Tool For?

Perfect for historians, classicists, students learning ancient systems, designers, and anyone working with formal documents, clocks, or movies where Roman numerals are used.

Why Convert to and from Roman Numerals?

Roman numeral conversion is essential for interpreting historical dates, understanding formal numbering systems in documents and clocks, and ensuring accuracy in academic, design, and entertainment contexts. Our tool provides instant, bidirectional conversion to bridge modern numbers with this classical notation.

Frequently Asked Questions

Is this Roman numeral converter free?

Are my input numbers or results stored online?

Can I convert both numbers to Roman numerals and Roman numerals to numbers?

What number range does the converter support?

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