Roman Numeral Converter – Roman ↔ Arabic Numbers Online

Convert Roman numerals to Arabic numbers and vice versa with this free online converter. Instantly transform numbers like XIV to 14 or 2024 to MMXXIV. Perfect for students, historians, and anyone using classical numbering. No download or registration required—quick, accurate Roman numeral conversion for numbers from 1 to 3,999.

Roman ↔ Arabic Numeral Converter
Conversion Direction

How to Use the Roman Numerals Converter

Conversion Direction:

  • Roman → Arabic:
    Convert Roman numerals (e.g. XXVI) to Arabic numbers (e.g. 26).
  • Arabic → Roman:
    Convert Arabic numbers (e.g. 26) to Roman numerals (e.g. XXVI).

How to use:

  1. Select the desired conversion direction.
  2. Enter your value in the Input area:
    • If converting Roman to Arabic, type a valid Roman numeral (e.g. XLII).
    • If converting Arabic to Roman, type a positive integer (e.g. 42) (Max. 3,999).
  3. The converted result will appear instantly in the Output area.
  4. Use Copy to copy the result, or Clear to reset and try another conversion.

Tips:

  • Roman numerals are case-insensitive (e.g. xiv and XIV are both valid).
  • Only positive integers are supported for conversion to Roman numerals.
  • Invalid entries will return an error or no result.
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