Log Base 2 Calculator
Use our log base 2 calculator to calculate log base 2 (log2) values instantly. Includes the log base 2 formula, how to calculate log base 2 on a scientific calculator, and how to do log base 2 on calculator (including TI-84 using change-of-base).
What is Log Base 2?
Log base 2 (written as log2(x)) answers the question: “2 to what power equals x?”
For example, log2(8) = 3 because 2^3 = 8.
Log base 2 is common in computer science, binary systems, information theory, and algorithms, which is why a log base 2 calculator is useful for quick checks.
Log Base 2 Formula
If your calculator doesn’t have a direct log2 button, you can use the change-of-base formula with log or ln.
This is the meaning of log base 2.
You can use log base 10 on most scientific calculators.
This works the same way using ln.
Because 2^3 = 8.
Because 2^5 = 32.
How to Use the Log Base 2 Calculator
- 1
Enter the value x (x must be greater than 0).
- 2
The calculator computes log base 2: log2(x).
- 3
Review the result and round if needed.
- 4
Optionally verify by checking that 2^(result) ≈ x.
Frequently Asked Questions
Use the change-of-base formula: log2(x) = log(x) ÷ log(2) (or ln(x) ÷ ln(2)).
If your calculator has no log2 button, enter log(x)/log(2) or ln(x)/ln(2).
Use the log or ln key with change-of-base: log(x) ÷ log(2) or ln(x) ÷ ln(2).
Look for a log base feature (sometimes “logBASE” or “log(a,b)”). If it’s not available, use log(x)/log(2).
On a TI-84, use log(x)/log(2) or ln(x)/ln(2). Both give the same log base 2 result.
The definition is log2(x) = y ⇔ 2^y = x. For calculators, log2(x) = log(x)/log(2).
x must be greater than 0. Logarithms of 0 or negative numbers are not defined in the real numbers.