Math Calculators
Log Calculator
Compute a logarithm of any base.
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About the Log Calculator
A logarithm answers 'what power of the base gives this number?' Enter a number and a base and the calculator returns the logarithm, plus the natural log (base e) for reference. It's essential for exponential-growth problems, decibels, pH, and anywhere logarithmic scales appear.
How to use the Log Calculator
- 01Enter your number and base.
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
What is a logarithm?
The exponent to which a base must be raised to produce a number. log₁₀(1000) = 3 because 10³ = 1000.
What is natural log?
The logarithm base e (≈ 2.718), written ln. It's the natural choice for continuous growth and calculus.