Roman Numerals Conversions
Convert Roman numerals and decimal numbers — I, V, X, L, C, D, M. Free converters for clocks, outlines, and education.
2 units · 2 conversions
Roman numerals use letters to represent values: I (1), V (5), X (10), L (50), C (100), D (500), M (1,000). Subtractive notation (IV for 4, IX for 9) reduces repetition.
Conversion follows fixed symbol rules rather than arithmetic multiplication. Our converter validates notation and maps between Roman strings and decimal integers for homework, document outlines, and clock faces.
Popular roman numerals conversions
Real-world example
A copyright line reads MMXXVI and you need the year in Arabic numerals. Converting gives 2026 — useful for quickly reading dates on buildings or film credits.
All roman numerals conversions
Roman Numerals units explained
- Decimal (Dec) · base unit
- Also: arabic, number
- Roman Numerals (Roman)
- Also: roman numerals
Frequently asked questions
- What is the largest standard Roman numeral?
- Traditional Roman numerals can represent large values with overlines or repeated M symbols; everyday use rarely exceeds the thousands (M).
- Is IIII used instead of IV on clocks?
- Some clock faces use IIII for aesthetic symmetry opposite VIII — both conventions appear in the wild.