Calculate the binary logarithm of a positive real number and verify the result against powers of 2.
Last updated: June 2026 | By Patchworkr Team
Log base 2, written log2(x), tells you the power you must raise 2 to in order to get x. It is also called the binary logarithm because it matches base-2 counting in computing.
Since 64 = 2^6, the calculator returns 6.
Can log2 be negative?
Yes. The result is negative whenever the input is between 0 and 1.
Why reject zero and negative numbers?
Binary logarithms are only defined for positive real numbers, so zero and negatives are invalid.
Does the tool accept decimals?
Yes. Any finite positive real number is accepted, including decimal and scientific notation values.
Is this useful outside computing?
Yes. It also appears in information theory, exponential growth, and any context where doubling matters.
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