Free Roman to Arabic Numeral Converter Online
Convert Roman numerals to Arabic numbers and Arabic numbers to Roman numerals (1–3999) with explanation of subtractive notation rules. — 100% free online utility, zero sign-up, zero paywalls, and private client-side processing.
How It Works
Enter Number
Type Arabic number (1-3999) or Roman numeral string.
Convert
Click convert or press Enter.
View Breakdown
See step-by-step decomposition of each Roman symbol.
Frequently Asked Questions
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