Roman Numerals to Number Converter
Paste a Roman numeral such as MMXXVI and get the decimal value back. The input is validated against standard notation, so malformed numerals are flagged rather than silently mis-read.
Runs in your browser — your text is never uploaded or stored.
Roman numeral
Number
How to Use
- 1.Type the Roman numeral, in upper or lower case.
- 2.Read the decimal number in the result box.
- 3.Copy the value wherever you need it.
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FAQ
Why is my numeral rejected?
Only standard notation is accepted: at most three repeats of a symbol and valid subtractive pairs such as IV, IX, XL and CM.
Is lower case allowed?
Yes — input is upper-cased before validation, so mmxxvi works.
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