You have probably seen them indicating the year of production at the end of TV programs and film credits, or to denote the number of sporting events like the XXIX Olympics in Beijing in 2008 (or maybe that should be the year MMVIII), and even in normal daily life on clocks and watches. Converting between Roman numerals and numbers which are denoted in Hindu-Arabic numerals using the digits 0 to 9 that we generally use in the Western world today is, however, often a tricky task to perform.

Hindu-Arabic (modern Western decimal number based on the digits 0 to 9):

Roman Numerals:

Correct a Roman Numeral:

Once again this is where our amphibian friend Springfrog hops to the rescue with another useful online conversion tool. Our Roman numeral conversion calculator will allow you to quickly and conveniently convert from Roman numerals to Hindu-Arabic numbers, or to go in the opposite direction and discover how a Roman numeral should be written starting with a normal Arabic number. Not only that, but the converter can even correct improperly-formed Roman numerals and display the correct version. An interesting example of an incorrectly formatted Roman numeral exists on Admiralty Arch in London for example, where the number MDCCCCX is carved permanently in stone for all to view. Just tap these numerals into the converter, click the button marked "Correct to properly-formatted Roman numerals" and you'll see how it really should be written in Roman Numerals. From there you can proceed to click on the "Convert to Hindu-Arabic decimal numerals" button to see the number displayed in our modern Hindu Arabic system of digits.

Another interesting fact is that there was no decimal point in Roman numerals, no negative numbers and there was nothing to signify zero. The Romans were a practical bunch, and the concept of a negative number was too abstract an idea. Similarly nothing was just the absence of anything so didn't need a number. Rather than have a decimal point, the Romans used only a very specific set of fractions basen on twelvths (in other words, what is known as a duodecimal system).

You'll therefore get an error message if you try to convert negative numbers or anything containing a decimal point. Attempting to convert zero from Hindu-Arabic will just result in the absence of anything.

Finally, as a fun fact, modern digital storage media can be conveted to Roman numerals! A CD equals 400 whereas a DVD, although improperly formatted, can be corrected to CMXCV which gives 995. Did the Romans of history have the foresight to know all that time ago that a DVD has more storage space than a CD? Can you make any more words that can be converted into numbers using the Roman numeral set of letters of IVXLCDM?

Have fun and happy converting!

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