1001 in Decimal
Binary 1001 equals 9 in decimal.
1001 in all number bases
Decimal9
Hexadecimal0x9
Binary1001
Octal11
Try another value
Edit this value or switch its base. Your changes are calculated in your browser with exact integer arithmetic.
Input base:
Decimal
9Hex
0x9Binary
0b1001Octal
0o11How 1001 converts from binary to decimal
Multiply each digit by 2 raised to its position (starting at 0 from the right), then add the results:
1× 23 = 1 × 8 = 8
0× 22 = 0 × 4 = 0
0× 21 = 0 × 2 = 0
1× 20 = 1 × 1 = 1
Sum: 9
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