Two-way conversion

Roman Numeral Converter Online

Convert numbers to Roman numerals—or decode Roman numerals back to numbers—in an instant. See the logic behind every answer with a clear, step-by-step breakdown.

Type any whole number from 1 to 3999.

Try an example

Roman numeral MMXXVI

2026 written in Roman numerals

How it is built

Roman numeral chart

Seven letters form every standard Roman numeral. Larger numbers come from combining these symbols and using subtraction pairs such as IV for 4 and IX for 9.

I1
V5
X10
L50
C100
D500
M1,000

How to use the Roman numeral converter

This free Roman numeral converter online handles both directions and updates as you type. There is no form to submit and nothing to install.

  1. Choose Number to Roman or Roman to Number.
  2. Enter a whole number from 1 to 3999, or a valid Roman numeral.
  3. Read the instant result and follow the breakdown to see how it works.
  4. Copy the answer, or select Reverse to convert it back the other way.

How Roman numerals work

Roman numerals normally add symbols from largest to smallest. When a smaller symbol appears before a larger one, it is subtracted instead. These six standard subtraction pairs keep numerals compact.

Ones: IV and IX

IV is 4 because I comes before V. IX is 9 because I comes before X.

Tens: XL and XC

XL is 40 because X comes before L. XC is 90 because X comes before C.

Hundreds: CD and CM

CD is 400 because C comes before D. CM is 900 because C comes before M.

Roman numeral converter FAQ

How do I convert a number to Roman numerals?

Select Number to Roman and enter a whole number from 1 to 3999. The Roman numeral and its place-value breakdown appear instantly. For example, 2026 becomes MMXXVI.

How do I convert Roman numerals to numbers?

Select Roman to Number and type letters from the Roman numeral system: I, V, X, L, C, D and M. Lowercase is accepted and changed to uppercase automatically.

What is 2026 in Roman numerals?

2026 is MMXXVI: MM represents 2000, XX represents 20 and VI represents 6.

Why is the maximum standard Roman numeral 3999?

Modern standard Roman numerals use ordinary letters for values from 1 through 3999. Larger historical notations require extra conventions, such as an overline to multiply a value by 1,000.

Is this online Roman numeral converter free and private?

Yes. The converter is free and needs no account. The calculation happens locally in your browser, so the value you enter is not uploaded by this tool.

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