Roman Numeral Converter

Roman numerals use seven symbols: I (1), V (5), X (10), L (50), C (100), D (500), M (1,000). Numbers are formed by adding symbols (XVII = 17) or using subtractive notation (IV = 4, IX = 9). This converter handles numbers 1 through 3,999.

Enter a number (1-3,999) to convert to Roman numerals.

Number

Key Takeaways

Seven symbols: I (1), V (5), X (10), L (50), C (100), D (500), M (1,000).
Subtractive notation: IV = 4, IX = 9, XL = 40, XC = 90, CD = 400, CM = 900.
Standard range: 1 (I) to 3,999 (MMMCMXCIX). No symbol for zero.
Common dates: MMXXVI = 2026, MCMXCIX = 1999, MM = 2000.
Still used on clock faces, in Super Bowl names, movie dates, and legal documents.

How Do Roman Numerals Work?

Roman numerals combine seven symbols to represent numbers. The basic rule is addition: symbols are placed left to right from largest to smallest, and you add their values. XVII = 10 + 5 + 1 + 1 = 17. The subtractive rule handles 4 and 9 patterns: when a smaller symbol appears before a larger one, you subtract it. IV = 5 − 1 = 4.

Maya Singh at Pinewood Falls High uses Roman numerals in her English class when writing essay outlines (I, II, III for major sections; A, B, C for subsections). She also encounters them on the cornerstone of the town library, which reads MCMXXVIII, which is 1928, the year it was built. Tom Brewer, a retired engineer who lives next door, taught her to decode it: M = 1000, CM = 900, XX = 20, VIII = 8.

Roman Numeral Reference Chart

Number	Roman	Number	Roman
1	I	20	XX
2	II	30	XXX
3	III	40	XL
4	IV	50	L
5	V	60	LX
6	VI	90	XC
7	VII	100	C
8	VIII	400	CD
9	IX	500	D
10	X	900	CM
11	XI	1,000	M
14	XIV	2,000	MM
15	XV	2,026	MMXXVI
19	XIX	3,999	MMMCMXCIX

Source: Standard Roman numeral notation

Subtractive Notation Rules

Subtractive notation avoids four consecutive identical symbols. The rules are precise:

Subtraction	Roman	Value	Replaces
I before V	IV	4	IIII
I before X	IX	9	VIIII
X before L	XL	40	XXXX
X before C	XC	90	LXXXX
C before D	CD	400	CCCC
C before M	CM	900	DCCCC

Source: Standard Roman numeral notation

Only I, X, and C can be used subtractively, and each can only precede the next two larger symbols. You cannot write IC for 99 (correct: XCIX) or VL for 45 (correct: XLV). This is a common mistake in homework assignments, as Maya Singh discovered when her teacher marked IL as incorrect for 49. The correct form is XLIX.

Where Are Roman Numerals Used Today?

Clock and Watch Faces

Many traditional clock faces use Roman numerals, with the notable convention of IIII for 4 instead of IV. The Pinewood Falls town clock in the square uses this style. High-end watch brands like Rolex continue this tradition on many of their dial designs.

Movie and Television Copyright

Film and TV credits often display the copyright year in Roman numerals. A movie released in 2026 shows MMXXVI in the end credits. This convention dates back to the early days of Hollywood and was originally intended to make the release year less obvious so films would seem "timeless."

Super Bowl and Major Events

The Super Bowl has been numbered with Roman numerals since Super Bowl V (1971). Super Bowl LX will be the 60th edition. The only exception was Super Bowl 50 in 2016, when the NFL used Arabic numerals because "L" alone did not look as impressive in marketing materials.

Academic and Legal Documents

Outlines use Roman numerals for major sections. Legal documents number articles and sections with Roman numerals. Textbook volumes, academic paper sections, and footnotes frequently use them. Preface pages in books are numbered with lowercase Roman numerals (i, ii, iii, iv).

For other number conversions, try the percentage calculator for percent math, the fraction calculator for fraction arithmetic, or the age calculator to convert birth years into exact ages.

This converter handles standard Roman numeral notation for numbers 1 through 3,999. Extended notation (vinculum) for numbers above 3,999 is not supported. Historical Roman numeral usage sometimes varied from modern standardized rules.

Frequently Asked Questions

What are the Roman numeral symbols and their values?

The seven Roman numeral symbols are: I = 1, V = 5, X = 10, L = 50, C = 100, D = 500, M = 1,000. All Roman numerals are built from combinations of these seven symbols using addition and subtraction rules.

How does subtractive notation work?

When a smaller symbol appears before a larger one, you subtract it. IV = 4 (5 − 1), IX = 9 (10 − 1), XL = 40 (50 − 10), XC = 90 (100 − 10), CD = 400 (500 − 100), CM = 900 (1000 − 100). Only I, X, and C can be used subtractively, and only before the next two larger symbols.

What is the largest number you can write in Roman numerals?

Using standard notation, the largest is 3,999 (MMMCMXCIX). Ancient Romans used a bar (vinculum) over symbols to multiply by 1,000 (so V̄ = 5,000 and X̄ = 10,000), but this extended notation is rarely used today.

Is there a Roman numeral for zero?

No. The Roman numeral system has no symbol for zero. The concept of zero as a number was introduced to Europe from Indian mathematics via Arabic scholars in the Middle Ages, centuries after Roman numerals were established.

What year is MMXXVI in Roman numerals?

MMXXVI = 2026. M = 1000, M = 1000, XX = 20, VI = 6. So 1000 + 1000 + 20 + 6 = 2026.

Where are Roman numerals still used today?

Roman numerals appear on clock faces, in movie copyright dates, Super Bowl numbering, book chapter and volume numbers, monarch names (Elizabeth II, Charles III), architectural cornerstone dates, outline formatting, and legal documents for numbering sections.

How often do people need to convert Roman numerals?

Most people encounter Roman numerals occasionally when reading clock faces, watching movie credits, referencing Super Bowls, or writing formal outlines. Students use them more frequently in history, Latin, and English classes. The converter is most useful when you encounter an unfamiliar combination and need a quick translation.