Roman Numeral Generator

What this generator does

Produces a number written as a Roman numeral, alongside its ordinary value. Useful for classroom work and for generating chapter or edition labels.

How to use this tool

1. Set a minimum and maximum.
2. Press generate for a random number and its Roman numeral form.
3. Generate again for a new one.

Worked examples

Format

MCMXCIV (1994)

Common use cases

• Learning or teaching Roman numerals
• Design elements needing a Roman numeral
• General curiosity

How this generator works

A number is drawn and converted using the subtractive convention — IV rather than IIII, CM rather than DCCCC — and converted back to check that it reads as the number it was made from. The round trip is the check that matters, since the subtractive rules have enough special cases that a converter is usually wrong somewhere before it is tested.

Limitations and good to know

• Roman numerals have no zero and no standard way of writing negative or fractional values, so the tool works only with positive whole numbers.
• Roman numerals have no zero and no negative numbers, so the range starts at 1.
• The upper limit is 3,999. Larger numbers need an overline notation that plain text cannot carry.
• The subtractive form is the modern convention. Historical inscriptions are inconsistent, and IIII still appears on clock faces.