Question 1

What is the largest number I can convert?

Accepted Answer

Up to 3,999,999. Numbers above 3,999 use extended notation with an overline (a bar over the numeral) to multiply by 1,000 — for example, V̄ represents 5,000.

Question 2

Why is there no Roman numeral for zero?

Accepted Answer

The Roman numeral system has no symbol for zero. It was not needed for counting items and arithmetic was done on an abacus. For this reason the tool only converts positive integers.

Question 3

Does the tool accept IIII and similar non-standard forms?

Accepted Answer

No. It expects canonical form (IV, not IIII; IX, not VIIII). If you paste a non-standard Roman numeral the tool shows an error so you know why.

Roman Numerals Converter

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