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Roman Numeral Converter
Type a number to see it in Roman numerals, or type Roman numerals to see the number. Every answer is taken apart letter by letter, so the next one is easier to do yourself.
How it's built
Type in either box and the numeral will be taken apart here.
The seven letters
Take-away pairs
A smaller letter written before a bigger one is taken away, so IV is 5 − 1.
Write the biggest values first, and never repeat a letter more than three times in a row (III, XXX, CCC, MMM). There's no Roman numeral for zero, which is why this stops at 3999.
Quick quiz
How fast can you crack them?
Roman numerals at primary school
In the National Curriculum for England, children learn to read Roman numerals up to 100 (I to C) in Year 4, then up to 1000 (M) in Year 5, when they also learn to recognise years written in Roman numerals. The quiz's "To 100" and "To 1000" settings match those two stages.
Spotting them in real life
Clock faces, kings and queens (Elizabeth II), chapter numbers, and the year a film or TV programme was made, often shown at the end of the credits. Look closely at a clock: many write 4 as IIII rather than IV. It's a tradition, but it isn't the standard form, so this converter will point out IV instead.
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