Our JavaScript Calculator has a limitation of the accuracy of your browser, usually 18 digits. The calculator will handle conversions from that number size to Roman Numerals, but the display would be as long as your desk. we suggest that you limit your decimal entry to 5 digits. The generally accepted maximum for display of a Roman Numeral is 4,999. We are not restricting you to that, but in the strictest acceptance of the guidlines of Roman Numerals, that is the cap. Enter a number (from 1 to unlimited?, such as 26) or a Roman Numeral (such as XXVI), and click the Convert button. You may clear the result field by clicking on Clear Result. You may also click on Convert another time and the result should be your initial entry.