🏛️ Roman Numerals Converter: Numbers to Roman and Back

How to use it

1. 1. Type into the one box

   Enter a number such as 2024 or Roman letters such as MMXXIV. The tool decides which way to convert, so there is no switch to set and no second box to fill in.

2. 2. Press Convert

   The answer appears in large type. A number from 1 to 3,999 becomes a Roman numeral, and a Roman numeral becomes a number. Pressing Enter works as well as the button.

3. 3. Read how it is built

   Under the answer you see the pieces added together, for example 1994 = M + CM + XC + IV, with the value of each piece in a small table. This shows the thousands, hundreds, tens and units.

4. 4. Use the symbol table

   The table of the seven symbols and their values sits beside the converter, with a short reminder of which symbols can be written before a larger one to subtract.

Ideas for class and home

• Copyright dates and film credits

  Roman numerals appear on clock faces, book chapters and the end of old films. Students find MCMLXXXV in a credit and use the tool to check that it means 1985.

• Rules of Roman numbers

  Ask students to guess why IIII or VX is refused, then read the message together. Finding the rule themselves makes the subtractive pairs far easier to remember than a list.

• History and Latin lessons

  Convert dates of battles, emperors and monuments as you study them. Seeing a year built from M, D, C, X and I gives a feel for how people counted and wrote.

• Numbering outlines and kings

  Check the numeral for a monarch such as Henry VIII, a Super Bowl number or an outline heading, before it goes on a worksheet or a display.