Roman and Arabic Numerals Converter
This tool instantly performs two-way conversion between Roman numerals and Arabic numbers.
It supports standard Roman numeral notation (I, V, X, L, C, D, M) with subtractive notation (IV, IX, XL, XC, CD, CM), covering the range 1–3999.
When you enter a value on one side, the other updates automatically. Incorrect inputs trigger clear error messages, and Roman numerals are automatically converted to standard uppercase form.
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