log base b
2
Math Utility
Logarithm Calculator
Calculate logarithms using a custom base and compare them against natural log and common log output in the same view.
Natural log (ln)
4.60517019
Common log (log10)
2
Frequently asked questions
What values are valid for logarithms?
The input value must be positive. For a custom base, the base must also be positive and cannot equal 1.
What is the difference between ln and log10?
ln means the natural logarithm with base e, while log10 means the common logarithm with base 10.
How is log base b calculated?
It uses the change-of-base formula: log_b(x) = ln(x) / ln(b).
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