Convert Arabic numbers to Roman numerals and Roman numerals to Arabic numbers for free. Supports 1–3999, includes symbol reference, and common examples.
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Roman numerals remain relevant across modern life in ways that many people don't initially realize — from movie copyright dates (MMXXIV) and Super Bowl numbering (LVIII) to watch faces, book chapter markers, architectural inscriptions, legal document outlines, and tattoo designs. Our free online Roman Numeral Converter makes converting between standard Arabic numbers and Roman numerals instant, accurate, and educational, whether you need to convert a single year or work through an entire list of numbers for a publication or design project. In Arabic → Roman mode, enter any whole number between 1 and 3999 to instantly receive the correct Roman numeral notation. The converter applies the full standard rule set, including the subtractive notation principles: IV (4), IX (9), XL (40), XC (90), CD (400), and CM (900). In Roman → Arabic mode, enter any Roman numeral string (uppercase or lowercase) to decode it to its Arabic equivalent, with strict validation ensuring only valid, correctly ordered Roman numeral sequences are accepted. A built-in symbol reference table shows all seven Roman numeral symbols (I=1, V=5, X=10, L=50, C=100, D=500, M=1000) with their values, and 16 clickable common examples — including historically significant years and milestone numbers — let you quickly explore the converter. Since all conversion logic is implemented in pure JavaScript client-side, your data stays entirely in your browser with no server calls, making this tool fast, private, and available even offline. Whether you're a student studying classical history, a designer adding a Roman numeral year to a logo, or a developer building a number formatting library, our Roman Numeral Converter delivers instant, validated, reliable results.
Select 'Arabic → Roman' or 'Roman → Arabic' mode.
Type a number (1–3999) or a valid Roman numeral string.
Click Convert or press Enter to see the result instantly.
Convert Arabic numbers to Roman numerals or Roman numerals to Arabic numbers.
Supports the full standard range of Roman numerals from I (1) to MMMCMXCIX (3999).
Strict validation ensures only valid Roman numeral sequences are accepted.
Built-in table showing all Roman numeral symbols (I, V, X, L, C, D, M) with values.
16 clickable examples for quick reference including 2024 = MMXXIV.
Copy the converted numeral or number to clipboard with one click.
In standard notation, the largest Roman numeral is MMMCMXCIX which equals 3999. Numbers beyond this require non-standard extensions.
No. The Romans had no symbol for zero. Roman numerals were only used for positive counting numbers starting from 1.
When a smaller value appears before a larger value, it is subtracted. For example, IV = 4 (5-1), IX = 9 (10-1), XL = 40, XC = 90, CD = 400, CM = 900.
Yes! Years like 2024 (MMXXIV) or 1994 (MCMXCIV) are fully supported within the 1–3999 range.
Our converter accepts both uppercase and lowercase input (e.g. xiv or XIV) and normalizes to uppercase.
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Convert between Arabic numbers and Roman numerals (1–3999)