Type a number or paste a Roman numeral into the calculator above, and get your conversion instantly. This Roman numeral converter handles numbers from 1 to 3,999 and works in both directions: numbers to Roman numerals and Roman numerals to numbers.
Whether you need a date in Roman numerals for a tattoo, a copyright line, or a school worksheet, the tool does the math for you.
Roman Numeral Converter Calculator
The converter accepts two types of input:
- A standard (Arabic) number like 2024, and it returns the Roman numeral equivalent (MMXXIV).
- A Roman numeral like XIV, and it returns the Arabic number (14).
Results appear as soon as you enter your value. No extra steps needed.
What is the range? The standard Roman numeral system covers 1 through 3,999. Zero and negative numbers do not exist in this numeral system. The Romans had no symbol for zero, and the subtractive rules break down above 3,999 without special notation like an overline (a bar above a numeral to multiply its value by 1,000).
How to Convert Numbers to Roman Numerals
Roman numerals use seven symbols. Each symbol maps to a fixed value:
| Symbol | Value |
|---|---|
| I | 1 |
| V | 5 |
| X | 10 |
| L | 50 |
| C | 100 |
| D | 500 |
| M | 1,000 |
Every Roman numeral is built by combining these symbols according to a few simple rules.
Number to Roman Conversion Symbol by Symbol
To convert a number to Roman numerals by hand, break it into place value chunks (thousands, hundreds, tens, ones) and translate each chunk separately.
Example: 1987
- 1,000 → M
- 900 → CM
- 80 → LXXX
- 7 → VII
Combine them left to right: MCMLXXXVII.
Start with the largest value that fits, subtract it, write the symbol, and repeat until you reach zero. The calculator above does exactly this, instantly.
Rules for Writing Roman Numerals
A few rules keep Roman numerals consistent and readable:
- Addition rule. When a smaller value follows a larger value, add them. VI = 5 + 1 = 6.
- Subtraction rule. When a smaller numeral precedes a larger symbol, subtract the smaller from the larger. IV = 5 − 1 = 4. IX = 10 − 1 = 9.
- Repetition limit. A symbol can repeat up to three times in a row (III = 3), but never four. That is why 4 is IV, not IIII.
- Only certain subtractions are valid. I can precede V and X. X can precede L and C. C can precede D and M. No other subtractive pairs are standard.
- Read left to right. Symbols are arranged from the largest value on the left to the smallest on the right, except where the subtraction rule applies.
Why can't Roman numerals represent zero or negative numbers? The system was built for counting and record keeping in ancient Rome. It has no placeholder concept like zero in our base-10 (decimal) system, and no mechanism for negative values.
Reading Roman Numerals
To translate Roman numerals to any number, scan the string from left to right:
- If the current symbol's value is less than the next symbol's value, subtract the current from the next. Move forward two positions.
- Otherwise, add the current symbol's value to your total. Move forward one position.
Example: XXIV
- X (10) + X (10) = 20 so far.
- I (1) is less than V (5), so subtract: 5 − 1 = 4.
- Total: 20 + 4 = 24.
Paste any Roman numeral into the converter above and it returns the Arabic number instantly. This works for simple values like VII (7) and longer strings like MMMCMXCIX (3,999).
Roman Numeral Date Converter
Dates in Roman numerals appear on buildings, film credits, and tattoos. Converting a full date means translating the month, day, and year individually.
Convert a Date to Roman Numerals
Follow these steps:
- Month. Write the month's number in Roman numerals (January = I, December = XII).
- Day. Convert the day (e.g., 25 = XXV).
- Year. Convert the year (e.g., 1990 = MCMXC).
Separate them with a dot or dash, depending on the date format you prefer.
Example: July 4, 1776
- Month: VII
- Day: IV
- Year: MDCCLXXVI
Result: VII · IV · MDCCLXXVI
The calculator handles each part for you. Enter the number for any month, day, or year and read the Roman numeral output directly.
Roman Numerals Used Today
Roman numerals are still used in many everyday contexts:
- Clock and watch faces. Many traditional clocks use Roman numerals for the hours.
- Super Bowl numbering. The NFL labels each Super Bowl with a Roman numeral (Super Bowl LVIII = 58).
- Events like the Olympics. Olympic Games numbering historically used Roman numerals.
- Copyright dates. Film and television credits often display the production year in Roman numerals (© MMXXIV).
- Book chapters and outlines. Volume numbers, chapter headings, and formal outlines use Roman numerals for hierarchy.
- Roman numeral tattoos. Birthdays, anniversaries, and meaningful dates are popular tattoo choices in Roman numeral format.
- Monuments and buildings. Cornerstones frequently show the construction year in Roman numerals.
The numeral system that originated in ancient Rome remains universally recognizable, which is why it endures thousands of years later.
Translate Roman Numerals to Any Number
Use the converter at the top of this page to translate any Roman numeral string back to a standard number. Enter the Roman numeral (for example, CDXLIV) and the calculator returns the Arabic number (444).
This also works as a quick way to check your own math if you are writing Roman numerals by hand for a worksheet, a design project, or a date inscription.
A few tips for accuracy:
- Use capital letters (M, D, C, L, X, V, I).
- Double check that subtractive pairs are valid (IV, IX, XL, XC, CD, CM).
- If your result seems off, confirm the symbols are in the correct left to right order from larger value to smaller value.
Related Calculators
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- Percentage Calculator for quick percent math.
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- Date Calculator to count days between two dates.