Roman Numeral Converter – Convert Numbers to Roman Numerals Free

Roman Numeral Converter Convert between Arabic numbers and Roman numerals

Supports numbers from 1 to 3,999,999. Numbers over 3,999 use standard overline notation (e.g., V̅ = 5,000).

Enter Arabic Number Enter a whole number between 1 and 3,999,999

Enter Roman Numeral Use I, V, X, L, C, D, M. For thousands, use overlines (e.g. V̅ for 5000).

About the Roman Numeral Converter

The Roman Numeral Converter converts Arabic numbers into Roman numerals and back again, instantly. Enter a number up to 3,999,999 or a Roman numeral string, and the tool returns an accurate conversion in either direction, including support for large numbers using standard overline notation.

This tool is built for students, teachers, writers, and anyone who needs quick, accurate Roman numeral conversions for dates, outlines, or design work. If you’re working with number formatting in text more broadly, the Case Converter can help clean up surrounding text, and the Word Counter is useful for checking length once your content is finalized.

eToolsKit Team tested this tool against a wide range of values — from single digits to numbers in the millions using overline notation — to confirm both directions of conversion return mathematically accurate results.

How to Use the Roman Numeral Converter

Choose a direction: Arabic to Roman or Roman to Arabic.
For Arabic to Roman, enter a whole number between 1 and 3,999,999.
For Roman to Arabic, enter a valid Roman numeral using I, V, X, L, C, D, M (with overlines for thousands).
Click Convert to see the result instantly.
Click Copy to copy the converted value to your clipboard.

Example Usage

Input (Arabic to Roman): 2026

Output: MMXXVI

Input (Roman to Arabic): MMXXIII

Output: 2023

For numbers above 3,999, an overline is used above a numeral to multiply its value by 1,000 (e.g. V̅ represents 5,000).

Frequently Asked Questions

This tool supports numbers up to 3,999,999 using standard overline notation for values above 3,999.

An overline (vinculum) above a Roman numeral multiplies its value by 1,000. For example, an overlined V represents 5,000 instead of 5.

Yes, switch to the “Roman to Arabic” tab, enter your Roman numeral, and the tool will return the equivalent Arabic number.

The tool will return an error message indicating an invalid format, since only the letters I, V, X, L, C, D, and M (with optional overlines) are valid.

Yes, this tool is completely free with no signup required.