Convert numbers to and from Roman numerals
Numbers above 3,999 use vinculum notation: a line above a numeral multiplies its value by 1,000.
So CMXCIXCMXCIXDCXCIII = 999,999,693.
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Roman Numerals: A Font for Importance
Arabic numerals are transparent: you see 42 and register the quantity instantly. Roman numerals are opaque: XLII requires a beat of translation. That friction is the feature. It forces a pause, adds formality, and signals that this number is special. Roman numerals aren't a number system anymore. They're a design language for importance.
Read more →Cornerstones and Permanence
Walk through any old city center and you'll find Roman numerals carved into stone: MCMXXIV on a courthouse, MDCCCLXXVI on a church. A cornerstone reading "1924" looks like a label. One reading MCMXXIV looks like a declaration. The angular shapes — all straight lines, no curves — are ideal for carving and engraving, weathering centuries of rain and wind.
Read more →Where do Roman numerals come from?
It is thought Roman numerals come from hand signals and tally marks. The stroke I represents a finger, the V represents the gap between thumb and fingers for five, and the X represents hands crossed for ten. The L, C, D, and M come from modifications of Greek letters like chi, theta, and phi to represent 50, 100, 500, and 1,000. Over time, these marks changed into the Latin letters people recognize today. There is no 0 in the Roman alphabet, as the concept for the number 0 didn't fully develop until India invented it around 600 CE / 10600 HE.