15 in Decimal
Hexadecimal 15 equals 21 in decimal.
15 in all number bases
Decimal21
Hexadecimal0x15
Binary0001 0101
Octal25
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Edit this value or switch its base. Your changes are calculated in your browser with exact integer arithmetic.
Input base:
Decimal
21Hex
0x15Binary
0b10101Octal
0o25How 15 converts from hexadecimal to decimal
Multiply each digit by 16 raised to its position (starting at 0 from the right), then add the results:
1× 161 = 1 × 16 = 16
5× 160 = 5 × 1 = 5
Sum: 21
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