Logarithm Calculator (Free)
Compute log base b of x using the change of base formula.
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Advanced Logarithm Tools
Compute natural logs, log tables, antilogarithms, and solve logarithmic equations with full workings.
Frequently Asked Questions
What is a logarithm?
A logarithm answers the question: to what power must the base be raised to produce a given number? log_b(x) = y means b^y = x.
What is the change of base formula?
log_b(x) = ln(x) / ln(b). This lets you calculate any logarithm using the natural logarithm (ln) available on scientific calculators.
What are common logarithm bases?
The most common bases are 10 (common logarithm, log), e ≈ 2.718 (natural logarithm, ln), and 2 (binary logarithm, used in computer science).