Roman Numeral Converter

Convert numbers to Roman numerals and back — 1 to 3999. Convert numbers to Roman numerals and Roman numerals to numbers instantly. Covers 1–3999 with subtractive notation explained. Free Roman numeral converter.

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Acerca de Roman Numeral Converter

Clock faces, movie sequels, book chapters and Super Bowls keep Roman numerals alive. This converter translates both directions across the classical range 1–3999: enter 2026 and get MMXXVI, paste XLVII and get 47. It applies standard subtractive notation (IV, IX, XL, CM) and flags invalid forms like IIII or VV, with a compact reference chart of the seven symbols and their values.

Cómo usar Roman Numeral Converter

Choose your direction.
Enter a number (1–3999) or a Roman numeral.
The conversion appears instantly.
Check the chart for how the symbols combine.

Características principales

Numbers → Roman numerals (1–3999)
Roman numerals → numbers with validation
Correct subtractive notation (IV not IIII)
Symbol reference chart included

Why does Roman numeration stop at 3999?

Standard notation has no symbol larger than M (1000); writing 4000 would need MMMM or the rarely used overline notation, so 3999 (MMMCMXCIX) is the classical limit.

What is subtractive notation?

Placing a smaller symbol before a larger one subtracts it: IV = 4, IX = 9, XL = 40, CM = 900. It replaced the older additive style of IIII for 4.

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