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Roman Numeral Converter

Convert numbers to Roman numerals and Roman numerals back to numbers, from 1 to 3999.

Convert Roman numerals

Result: —
Working: —
Roman numerals are supported from 1 (I) to 3999 (MMMCMXCIX). Invalid input is rejected with a warning.

How to use the Roman Numeral Converter

  1. Type a number such as 1994 or a Roman numeral such as MCMXCIV.
  2. Leave the direction on detect automatically, or choose the direction yourself.
  3. Read the result and the working, then copy it with one click.

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Frequently Asked Questions

Common questions about the free online roman numeral converter.

Type the number in the box and the Roman numeral appears as you type. The working line shows how the numeral is built from each symbol.
Enter a Roman numeral such as MCMXCIV and the converter returns 1994, with the value of every symbol shown in the working line.
Roman numerals from 1 to 3999. There is no standard Roman symbol for zero or for values of 4000 and above, so those inputs are rejected.
Only canonical forms are accepted. Strings such as IIII or IC are not valid Roman numerals, so the converter shows a warning instead of a wrong.
I is 1, V is 5, X is 10, L is 50, C is 100, D is 500 and M is 1000. A smaller symbol placed before a larger one is subtracted, as in IV for 4.
Subtractive notation is the standard modern form, so IV is the correct way to write 4. The older additive form IIII survives only on some clock faces.
No. The conversion runs entirely in your browser, so nothing you type is uploaded, logged or stored.
Yes, the page is responsive and works on phones, tablets and desktop browsers.
Yes, the Roman numeral converter is free and unlimited, with no account needed.

Last updated: October 10, 2026