Roman Numerals

Roman numerals are a non-positional numbering system used in ancient Rome (especially during the time of Caesar). It is based on the combination of seven capital letters representing fixed values, added or subtracted according to their position.

Roman numeration uses 7 letters corresponding to 7 numbers. Roman digits chart from 1 to 1000:

Beyond several thousands, there are no letters to represent these numbers.

However, some archaic scripts (more rare) used 4 other symbols

Roman numerals are based on two main rules:

— (1) If a letter of lesser or equal value than the preceding letter is to its right, their values are added.

— (2) A unit (I), ten (X), or hundred (C) letter placed immediately to the left of a larger letter is subtracted from it, provided that the value of the larger letter does not exceed ten times that of the larger letter. Thus, I (1) can precede V (5) or X (10), X (10) can precede L (50) or C (100), and C (100) can precede D (500) or M (1000)

Use dCode converter for other numbers.

The program automatically detects whether the number is in Arabic or Roman numerals and makes the conversion/translation.

Roman numeration does not permit writing large numbers, beyond 9999 the program will display the number of thousands separately. This writing is not standardized but remains comprehensible.

The program is very permissive and allows badly formed Roman numbers not complying with the rule (2). This is a software freedom, not a rule of the Roman system.

Romans did not use the zero, for them it was not a digit but a state of emptiness, so they did not write it (the absence of a number indicates zero).

Four is written IV, however, this software indicates that IIII = 4, unusual, IIII is a variant of IV which is tolerated. It can be found today (typically in watches, or clocks).

There is no specific way to write a date (or a birthdate), except to write the number of the day, the month and the year separately.

dCode has a tool to write a date in latin.

In some European countries, the centuries are sometimes written in Roman numerals.

Numbers above 10000 were not thinkable, without any calculation tool, they were useless. If you wish to write a value of hundreds of thousands, one can imagine writing hundreds of M at the beginning of the number.

The Romains do not conceive neither the negative names nor the decimals. The sign − is a modern convention that allows you to understand it.

Using decimal numbers is very few documented in history books, however, it is probable that they used fractions, including a duodecimal currency system (base 12) which allowed sharing by 2, 3, 4, 6 and 12 without decimal places.

Roman numerals were born with Antique Rome, so starting at the 7th century BC. For example, they were used with Latin.

Roman numerals have been added to the Unicode standard, they encode by a single character each number from 1 to 12 (used in clocks and watches) and 8 other numbers meaning:

In theory, in Roman numerals, any symbol (letter) is repeated a maximum of three times consecutively.

Roman numerals can, however, be written with four identical letters in a row, but this remains rare or incorrect in standard historical notation.

Roman numerals are learned at school in primary school but are rarely used except in mathematics or history. Today's uses are limited to symbolic (clocks), historical (writing centuries) but also aesthetic (many tattoos use Roman numerals).