Roman Numeral
Convert both ways
123 → CXXIII
Decimal → Roman
IX → 9
Roman → Decimal
I V X L C D M
Reference chart
‹
Decimal → Roman
1
↓
I
−1000
−100
−10
−1
+1
+10
+100
+1000
Reset to 1
Range 1–3999
‹
Roman → Decimal
—
↓
0
I
1
V
5
X
10
L
50
C
100
D
500
M
1000
⌫ Delete
Clear
Pick symbols to build a numeral
‹
Reference
Symbols
I
1
V
5
X
10
L
50
C
100
D
500
M
1000
Subtractive
IV
4
IX
9
XL
40
XC
90
CD
400
CM
900
Done