Convert Roman numerals
Easily convert Roman numerals to common numbers and vice versa. Convert directly from I to MMMCMXCIX (1–3999). Fast, free, and no installation required.
Roman Numerals Converter
Convert Roman numerals – fast and easy
With this Roman numeral calculator , you can instantly convert a regular number to Roman numerals, or convert a Roman numeral back to an Arabic numeral. The tool works for values from 1 to 3999 , which is the standard range within the classical Roman numeral system.
Roman numerals are formed with the symbols:
- I = 1
- V = 5
- X = 10
- L = 50
- C = 100
- D = 500
- M = 1000
Combinations of these letters result in larger numbers. For example:
- IV = 4
- IX = 9
- XL = 40
- XC = 90
- CM = 900
- MMXXIV = 2024
How does the conversion work?
The Roman system uses both addition and subtraction:
- When a smaller value precedes a larger one, it is subtracted (for example IV = 5 − 1).
- When a smaller value follows a larger one, they are added together (for example VI = 5 + 1).
Our calculator automatically checks whether the entered Roman notation is correct and prevents incorrect combinations such as IIII or VV.
Where are Roman numerals used?
You can still find Roman numerals in:
- Bells (for example on church and tower bells)
- Book chapters and prefaces
- Dates on buildings
- Film and event editions (e.g. edition XXV)
- Royal names such as Louis XIV
Why use this Roman numerals tool?
✔ Immediate results without reloading ✔ Checks for correct notation ✔ Suitable for school, study, and general use ✔ Free and unlimited use
Whether you want to convert a year, check a chapter number, or understand exactly how Roman numerals work — this converter offers a fast and reliable solution.