Logarithm in Any Base
A logarithm asks which exponent raises the base to the target value. The change-of-base formula allows arbitrary positive bases.
Logarithm in Any Base
Algebra · 2 inputs
How to use this calculator
- Enter positive value in number.
- Enter base in number.
- Select Calculate and keep the output unit with the answer.
Before you use the answer
Choose the reference quantity before interpreting the number. A ratio, a percentage and a percentage-point difference may use the same observations while answering different questions. For recorded data, keep the original values beside the summary so an unexpected result can be traced back to its inputs.
The base cannot equal one. Both the base and the argument must be positive for this real-valued tool.
Does it save my inputs?
No calculation history is stored by this website. The calculator works locally in your browser. See the privacy policy for hosting and contact details.
Why might a result be approximate?
Measurement uncertainty, ideal-model assumptions and floating-point rounding can all matter. Displaying more digits does not improve the original measurement.
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