Logarithm to a chosen base
Calculate logarithm to a chosen base and see the working behind your result.
Inputs
Use the units shown—
Enter your values and select Calculate.
Formula & explanation
logᵦ(x) = ln(x)/ln(b)
Variables & units
- Positive number
- Numeric value · minimum 0.000001, maximum 1000000
- Logarithm base
- Numeric value · minimum 0.000001, maximum 1000000
Worked example
log₁₀(100) = 2.
Assumptions
The number and base must be positive; the base cannot be one.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
Use the default input values to find the answer. The reset icon restores those values.
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