What number range can this Roman numeral converter handle?

The converter supports standard Roman numerals from 1 to 3999, which covers most practical uses such as dates, clocks, chapters, and Super Bowl numbers.

How do subtractive Roman numerals work?

When a smaller numeral appears before a larger numeral, it is subtracted. Common examples are IV for 4, IX for 9, XL for 40, XC for 90, CD for 400, and CM for 900.

Can I convert Roman numerals back to regular numbers?

Yes. Enter a Roman numeral such as MCMXCIV and the tool converts it back to an Arabic number instantly.

Roman Numeral Converter

Convert in both directions instantly. Supports standard Roman numerals from 1 to 3999.

Enter Roman Numeral or Number:

Quick starts: tap a common year or numeral.

Roman numeral rules at a glance

Numerals usually go from largest to smallest (for example, VIII = 8).
If a smaller value appears before a larger one, subtract it (IV = 4, IX = 9).
Use standard range 1-3999 for modern Roman numeral notation.

Result will appear here

Try related tools

Continue with Word Counter, Date Calculator, and Alphabetize.

Understanding Roman Numerals

Roman numerals are a numeral system that originated in ancient Rome and remained the usual way of writing numbers throughout Europe well into the Late Middle Ages. They are based on combinations of letters from the Latin alphabet: I, V, X, L, C, D, and M.

How Roman Numerals Work

Roman numerals are written by combining the following letters and their values:

I: 1
V: 5
X: 10
L: 50
C: 100
D: 500
M: 1000

The numerals are usually written in descending order from left to right. However, in a few specific cases, a smaller numeral can precede a larger numeral to indicate subtraction. For example:

IV: 4 (5 - 1)
IX: 9 (10 - 1)
XL: 40 (50 - 10)
XC: 90 (100 - 10)
CD: 400 (500 - 100)
CM: 900 (1000 - 100)

Examples

Example 1

MCMLIV:
M = 1000
CM = 900
L = 50
IV = 4
Total: 1000 + 900 + 50 + 4 = 1954

Example 2

MMXXI:
M = 1000
M = 1000
X = 10
X = 10
I = 1
Total: 1000 + 1000 + 10 + 10 + 1 = 2021

Popular Usages

Clocks and Watches: Roman numerals are often used on clock faces.
Book Chapters and Movie Sequels: They are commonly used to denote chapters, volumes, and sequels (e.g., Chapter IV, Rocky II).
Monuments and Buildings: Many monuments and buildings have their construction dates inscribed in Roman numerals.
Super Bowls: The NFL uses Roman numerals to number the Super Bowl games (e.g., Super Bowl LIII).
Royalty and Popes: Roman numerals are used to distinguish between monarchs and popes with the same name (e.g., Queen Elizabeth II, Pope John Paul II).

Understanding Roman numerals can be useful in various contexts, from reading historical documents to interpreting modern-day references. Use our Roman Numeral Converter to quickly convert between Roman numerals and numbers.

Roman Numeral Converter FAQ

What is the valid range for conversion?

This converter supports numbers from 1 to 3999, which is the modern standard range used for Roman numerals.

Why are some values written with subtraction (like IV)?

Roman numerals use subtractive notation in specific cases to keep numbers compact. For example, IV means 4 (5 minus 1), IX means 9, and CM means 900.

What if I need related everyday tools?

You can also try our Date Calculator, Word Counter, and Alphabetize.