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Roman Numeral Converter

Convert a whole number from 1 through 3999 into a Roman numeral, or read a numeral back into a number.

What is Roman Numeral Converter?

A Roman numeral converter turns whole numbers from 1 through 3999 into standard numerals, and reads those numerals back into numbers. Values above 3999 are not supported.

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Roman Numeral Converter — Numbers 1 through 3999 — Tools Star Hub

What this tool does

Convert whole numbers from 1 through 3999 to standard Roman numerals, and convert those numerals back to numbers.

How to use

  1. Choose number to Roman or Roman to number.
  2. Enter a number from 1 through 3999, or a numeral using I, V, X, L, C, D, and M.
  3. Press Convert.

Examples

  • 1994

    1994 is MCMXCIV.

Main features

  • Standard subtractive notation.
  • A reverse conversion.
  • Rejection of numerals that are not the standard form.

How it works

The page builds numerals from M, CM, D, CD, C, XC, L, XL, X, IX, V, IV, and I. A Roman string is accepted only when it is the standard form of its value. IIII, IC, and IL are rejected. Numerals above 3999, including vinculum notation, are not supported.

Tips

  • 4 is IV, not IIII.
  • 9 is IX, not VIIII.

Limitations

The range is 1 through 3999. Zero, negatives, and larger numbers are rejected.

See the disclaimer for what these tools do not cover.

FAQ

How do you convert a number to a Roman numeral?
The page uses standard subtractive notation. 4 is IV, 9 is IX, 40 is XL, and 3999 is MMMCMXCIX.
What numbers are supported?
Whole numbers from 1 through 3999.
Why is IIII rejected?
IIII is not the standard form of 4. The standard form is IV.
Can numerals above 3999 be converted?
No. Extended notation for larger numbers is not supported.
Can a numeral be turned back into a number?
Yes, when it is a standard numeral from 1 through 3999.
Are these numbers sent to a server?
No. The number or the numeral is converted in this tab. It is not uploaded.

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