Roman Numeral Converter

By CalculatorInn Team · Updated: 2026-03-22 · Free & accurate · Instant results

Convert between Roman numerals (I, V, X, L, C, D, M) and standard Arabic numbers (1, 2, 3...).

Interactive Roman Numeral Converter

JavaScript is required for the interactive calculator. Enable JavaScript to use this tool.

How to Use This Calculator

Step-by-Step Instructions

  1. Enter your enter number (1-3999)
  2. Enter your roman numeral
  3. Enter your arabic number
  4. Enter your characters
  5. Results appear instantly — no button needed

Formula

Mathematical Formula

Decompose into 1000s, 100s, 10s, 1s using Roman symbols

How It Works

Decompose into 1000s, 100s, 10s, 1s using Roman symbols

Frequently Asked Questions

How does this work?

Enter your values in the fields above and the calculator will compute results instantly using the formula shown.

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