Logarithm Calculator
Logarithms to any base, plus ln, log10 and log2.
Frequently Asked Questions
What does a logarithm actually ask?
It asks: to what power must the base be raised to get this number? Log base 10 of 1000 is 3 because 10^3 = 1000. Logarithms are the inverse operation of exponents.
How are logs to any base calculated?
By the change-of-base formula: log_b(x) = ln(x) / ln(b). Any scientific calculator with only a natural log key can therefore compute a logarithm to any base.
Where are logarithms used?
They measure things that span huge ranges: decibels for sound, the Richter scale for earthquakes, pH for acidity, and growth or decay rates in finance and biology.
Is the Logarithm Calculator free, and is my data private?
Yes. It is completely free and every calculation runs locally in your browser, so the numbers and dates you enter are never uploaded, stored, or shared with anyone.
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