What range is supported?

Numbers 1–3999 and their Roman equivalents. Zero is not represented in standard Roman numerals.

Can I convert both ways?

Yes. Enter a number to get Roman numerals, or enter Roman numerals to get the decimal number.

Yes. Conversion runs entirely in your browser.

Convert between Roman numerals and numbers (1–3999) in your browser. Enter Roman (e.g. MMXXIV) or a number—free and client-side.

Number → RomanRoman → Number

Number (1–3999)

What range is supported?: Numbers 1–3999 and their Roman equivalents. Zero is not represented in standard Roman numerals.
Can I convert both ways?: Yes. Enter a number to get Roman numerals, or enter Roman numerals to get the decimal number.
Is it free?: Yes. Conversion runs entirely in your browser.

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