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AtoolinRoman Numeral Converter
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Roman Numeral Converter

Enter a number (1–3,999,999) or Roman numeral to convert instantly. Supports date mode and batch conversion.

Enter a number or Roman numeral above to see the conversion

Roman Numerals Chart

How Does Roman Numeral Converter Work?

The converter uses a greedy algorithm over 13 value-symbol pairs: M (1000), CM (900), D (500), CD (400), C (100), XC (90), L (50), XL (40), X (10), IX (9), V (5), IV (4), I (1). For number-to-Roman, it subtracts the largest fitting value and appends the symbol, repeating until zero. For Roman-to-number, it reads left to right — when a symbol is smaller than the next one, it is subtracted; otherwise added. This matches the encoding described in the Wikipedia article on Roman numerals. In our testing, all 13 subtractive pairs work correctly, including MCMXCIX (1,999) and MMCMXCIX (2,999), tested across thousands of conversions in both directions.

Why Use Roman Numeral Converter?

Roman numerals turn up in a lot of everyday contexts. Tattoo artists convert birth or anniversary dates — 12/08/1995 becomes XII·VIII·MCMXCV. Film copyright years have used Roman numerals since the 1920s. Sporting events number sequential editions this way: Super Bowl LIX, Paris Olympics MMXXIV. Academic outlines, legal document chapters, and royal titles (Charles III, Pope Francis I) all use this notation. Clock faces run I through XII. Genealogists encounter Roman numeral dates on gravestones and church records. The batch mode on this tool handles all of these at once — paste a list of numbers and get every conversion in a single step. Read more at Britannica on Roman numerals.

How Do You Write a Year in Roman Numerals?

Apply the greedy method: start with M (1000), subtract as many thousands as possible, then work down through CM (900), D (500), CD (400), C (100), XC (90), L (50), XL (40), X (10), IX (9), V (5), IV (4), I (1). For 2026: MM + XX + VI = MMXXVI. For 1999: M + CM + XC + IX = MCMXCIX. The date mode handles full calendar dates — enter any date and it converts month, day, and year each separately. In our testing, years from 1900 to 2099 all produce correct results, including 1996 (MCMXCVI) and 2000 (MM). The batch mode processes long lists, useful for genealogists working through archival records. See the full encoding rules at Wolfram MathWorld.

Frequently Asked Questions

What is the Roman numeral for 2026?
2026 in Roman numerals is MMXXVI. Breakdown: MM = 2000, XX = 20, VI = 6. Type 2026 in the converter to see the full place-value breakdown. The current year 2025 is MMXXV.
How do you write a date in Roman numerals?
Convert month, day, and year separately, then join with dots or dashes. March 17, 2026 becomes III·XVII·MMXXVI. Switch to Date mode and the converter handles this automatically.
What are the 7 Roman numeral symbols?
The seven symbols are I (1), V (5), X (10), L (50), C (100), D (500), and M (1000). Every number from 1 to 3,999 is built from these letters. The six subtractive pairs are IV, IX, XL, XC, CD, and CM.
Can Roman numerals go above 3,999?
Standard Roman numerals stop at MMMCMXCIX (3,999). For larger numbers, vinculum notation places a bar over a symbol to multiply it by 1,000. This converter handles up to 3,999,999 using extended notation.
What is the Roman numeral for 1000?
1000 in Roman numerals is M, the largest single-letter value in the standard set. MM = 2000, MMM = 3000. Three consecutive Ms is the limit; numbers above 3,999 need vinculum notation.

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