Arabic numerals:

Roman numerals:

Arabic numerals |
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0 | ||||

1 | M | C | X | I |

2 | MM | CC | XX | II |

3 | MMM | CCC | XXX | III |

4 | CD | XL | IV | |

5 | D | L | V | |

6 | DC | LX | VI | |

7 | DCC | LXX | VII | |

8 | DCCC | LXXX | VIII | |

9 | CM | XC | IX |

The converter lets you go from arabic to roman numerals and vice versa. Simply type in the number you would like to convert in the field you would like to convert from, and the number in the other format will appear in the other field. Due to the limitions of the roman number system you can only convert numbers from 1 to 3999.

To easily convert between roman and arabic numerals you can use the table above. The key is to handle one arabic digit at a time, and translate it to the right roman number, where zeroes become empty. Go ahead and use the converter and observe how the table shows the solution in realtime!

2018-07-20 | 08:37:45 |

MMXVIII-VII-XX | VIII:XXXVII:XLV |

Here is the current date and time written in roman numerals. Since the roman number system doesn't have a zero, the hour, minute, and second component of the timestamps sometimes become empty.

The number 3999 is divisble by 3, 31, 43, 93, 129 and 1333 and can be prime factorized into 3×31×43.

3999 as a binary number: 111110011111

3999 as an octal number: 7637

3999 as a hexadecimal number: F9F

Below are the numbers MMMCMXCIII through MMMCMXCIX, which are close to MMMCMXCIX. The right column shows how each roman numeral adds up to the total.

3993 | = | MMMCMXCIII | = | 1000 + 1000 + 1000 + 1000 − 100 + 100 − 10 + 1 + 1 + 1 |

3994 | = | MMMCMXCIV | = | 1000 + 1000 + 1000 + 1000 − 100 + 100 − 10 + 5 − 1 |

3995 | = | MMMCMXCV | = | 1000 + 1000 + 1000 + 1000 − 100 + 100 − 10 + 5 |

3996 | = | MMMCMXCVI | = | 1000 + 1000 + 1000 + 1000 − 100 + 100 − 10 + 5 + 1 |

3997 | = | MMMCMXCVII | = | 1000 + 1000 + 1000 + 1000 − 100 + 100 − 10 + 5 + 1 + 1 |

3998 | = | MMMCMXCVIII | = | 1000 + 1000 + 1000 + 1000 − 100 + 100 − 10 + 5 + 1 + 1 + 1 |

3999 | = | MMMCMXCIX | = | 1000 + 1000 + 1000 + 1000 − 100 + 100 − 10 + 10 − 1 |

Roman numerals originate, as the name suggests, from the Ancient Roman empire. Unlike our position based system with base 10, the roman system is based on addition (and sometimes subtraction) of seven different values. These are symbols used to represent these values:

Symbol | Value |

I | 1 |

V | 5 |

X | 10 |

L | 50 |

C | 100 |

D | 500 |

M | 1000 |

For example, to express the number 737 in roman numerals you write DCCXXXVII, that is 500 + 100 + 100 + 10 + 10 + 10 + 5 + 1 + 1. However, for the numbers 4 and 9, subtraction is used instead of addition, and the smaller number is written in front of the greater number: e.g. 14 is written as XIV, i.e. 10 + 5 − 1, and 199 is expressed as CXCIX i.e. 100 + 100 − 10 + 10 − 1. It could be argued that 199 would be more easily written as CIC, but according to most common definition you can only subtract a number that is one order of magnitude smaller than the numbers you're subtracting from, meaning that IC for 99 is incorrect.

Roman numerals are often used in numbered lists, on buildings to state the year they were built, and in names of regents, such as Louis XVI of France.

Feel free to link to this site if you find it useful. It's also possible to link directly to specific numbers, such as roman-numerals.info/MMDXLVII or roman-numerals.info/782. You can also link to intervals, for instance roman-numerals.info/1-100 or roman-numerals.info/1980-2020, to see the numbers in a list format.