Convert between Roman numerals and Arabic numbers online. Supports 1-3999 range with bidirectional conversion. | No registration Β· Data never leaves your browser
Zero dependencies Β· Works offlineπ’ Roman Numerals Converter
π Roman Numeral Chart
I = 1V = 5X = 10L = 50
C = 100D = 500M = 1000
IV = 4IX = 9XL = 40XC = 90
CD = 400CM = 900
Updated: 2026-07-25
Roman Numerals Converter: calculation logic
The core calculation logic:
next= map[r[i+1]] || 0
Understanding Arabic β Roman
- Arabic β Roman
- Roman β Arabic
- Enter number (1-3999)
- Enter Roman numeral