# Roman numeral converter

Convert between numbers and Roman numerals

Use it at https://www.quicktoolz.com/tools/roman-numeral-converter. From QuickToolz.

Roman numerals use seven letters: I is 1, V is 5, X is 10, L is 50, C is 100, D is 500 and M is 1,000. Add the values from left to right, but a smaller letter before a larger one is subtracted. So IX is 9, and MMXXVI is 2,026.

## How it works

Write the largest symbol that fits, subtract it, then repeat.

We follow the standard modern form, which goes from 1 to 3,999. Four in a row, such as IIII, isn’t standard, so we explain the right form.

Worked example: 2,026 is 1,000 + 1,000 + 10 + 10 + 5 + 1, which is MMXXVI. A smaller symbol before a larger one means subtract, so IV is 4.

## Examples

| Number | Roman numeral |
| --- | --- |
| 4 | IV |
| 9 | IX |
| 40 | XL |
| 90 | XC |
| 400 | CD |
| 1999 | MCMXCIX |
| 2026 | MMXXVI |
| 3999 | MMMCMXCIX |

## What this tool doesn't cover

- Numbers above 3,999 need special marks, which this doesn’t support.
- There is no Roman numeral for zero.

## Questions

### Why is 4 written IV?

A smaller letter before a larger one means subtract, so IV is 5 minus 1.

### What is the largest number?

In the standard form, it’s 3,999, written MMMCMXCIX.

### Is there a Roman numeral for zero?

No. The Roman system had no symbol for zero.

### How do I read Roman numerals?

Add the values from left to right, but subtract a smaller value that comes before a larger one. So XIV is 10 + 5 − 1, or 14.

### How do I write a year in Roman numerals?

Break it into thousands, hundreds, tens and ones. For example, 2026 is MM, XX and VI, which makes MMXXVI.

## Sources

- [Encyclopaedia Britannica: Roman numeral](https://www.britannica.com/topic/Roman-numeral)