What is the range of numbers supported by the Roman Numeral Converter?

The converter supports numbers from 1 to 3999, which is the traditional range for Roman numerals. Numbers above 3999 require special notation like parentheses or overlines that aren't commonly used today.

Why does the converter reject some Roman numerals?

The converter validates Roman numerals according to traditional rules. For example, IIII (4) is invalid because the same symbol cannot repeat more than three times. The correct form is IV.

Can I convert large numbers to Roman numerals?

Traditional Roman numerals only go up to 3999 (MMMCMXCIX). For larger numbers, modern notation uses parentheses or overlines, but these aren't supported by this converter as they're not commonly used.

How do Roman numerals work?

Roman numerals use letters (I=1, V=5, X=10, L=50, C=100, D=500, M=1000) with additive and subtractive rules. Smaller values before larger ones subtract (IV=4), while same or larger values add (VI=6).

Are lowercase Roman numerals valid?

While Roman numerals are traditionally uppercase, the converter accepts both uppercase and lowercase input for user convenience and automatically converts them to uppercase for processing.

What are some common uses for Roman numerals today?

Roman numerals are still used in clocks, book chapters, movie credits, monarch names (Elizabeth II), sporting events (Super Bowl XL), and formal outlines in legal and academic documents.

Roman Numeral Converter

Convert between Roman numerals and Arabic numbers

roman

numeral

numbers

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Quick Presets

Common conversions for quick testing

Input & Settings

Choose a direction, enter a value, and convert in one step.

Arabic Number

How it works: Converts between Arabic numbers (1-3999) and Roman numerals. Uses subtractive notation (IV=4, IX=9, XL=40, XC=90, CD=400, CM=900).

Roman Numeral Reference

Basic Symbols

I = 1

V = 5

X = 10

L = 50

Advanced Symbols

C = 100

D = 500

M = 1000

Subtractive Notation

IV = 4

IX = 9

XL = 40

XC = 90

More Examples

CD = 400

CM = 900

MMM = 3000

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