Developer · free
Roman Numeral Converter
Convert between Roman numerals and decimal numbers. Supports values from 1 to 3,999.
Numbers from 1 to 3,999, using standard subtractive notation (IV, IX, XL, XC, CD, CM).
Result
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Quick reference
I = 1, V = 5, X = 10L = 50, C = 100
D = 500, M = 1000MMXXV = 2025
About the Roman Numeral Converter
Convert between Roman numerals and decimal numbers. Supports values from 1 to 3,999.
The conversion happens in your browser. Nothing you type is sent anywhere.
How to use the Roman Numeral Converter
- Step 1Pick whether you are converting a number to Roman numerals or the other way round.
- Step 2Type your value in the field.
- Step 3Press Convert, or press Enter, to see the result instantly.
What you get
- Both directions in one tool
- Standard subtractive notation
- Values from 1 to 3,999
- Runs in your browser, no sign-up
Roman Numeral Converter — FAQ
What is the largest number Roman numerals can write?
With the standard symbols, 3,999 is the limit (MMMCMXCIX). Larger numbers need an overline, which ordinary typing cannot show.
Why is 4 written as IV and not IIII?
Subtractive notation places a smaller symbol before a larger one to mean subtraction: IV is 5 minus 1. Clock faces sometimes use IIII by tradition, but IV is standard today.
How do I read MCMXCIV?
Break it into M (1000), CM (900), XC (90) and IV (4), then add: 1994. Symbols are read left to right, subtracting when a smaller value precedes a larger one.
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