Roman Numeral Converter
Enter a whole number in the Number field (sample default is 2026) and the Roman string appears below at once. Values outside 1–3999 show Enter 1-3999 instead of a fake numeral.
Updated 2026-08-03 · math
MMXXVI
About this tool
This converter uses the standard Roman map with subtractive pairs such as CM, CD, XC, XL, IX, and IV. It truncates decimals, then greedily subtracts values from 1000 down to 1. There is no reverse Roman-to-Arabic mode on this page.
How to use
- Open the converter: Load this page so the Number input and result area are visible.
- Type the number: Enter an integer between 1 and 3999 (the sample starts at 2026).
- Read the Roman output: Watch the result update live as you change the Number field.
- Fix out-of-range values: If you see Enter 1-3999, adjust the value into the supported range.
Common use cases
- Turn a year or chapter number into Roman numerals for a title page or outline.
- Check homework answers that expect IV, IX, XL, or CM forms.
- Prepare clock faces, monument captions, or classic list markers from Arabic digits.
Tips
- Stay within 1–3999; 0, negatives, and 4000+ are rejected.
- Decimals are truncated before conversion, so 12.9 becomes XII.
FAQ
What range does this tool accept?
Only integers from 1 through 3999. Anything else shows Enter 1-3999.
Does it convert Roman numerals back to numbers?
No. This page only converts Arabic numbers into Roman numerals.
How are values like 4, 9, 40, or 900 written?
With subtractive notation such as IV, IX, XL, and CM.
Is my number uploaded to a server?
Conversion runs in your browser as you type; no account is required.