Logarithm Calculator

Calculate logarithms with any base, natural log, and common log

Logarithm Formulas

Common Logarithm (Base 10):
log₁₀(x) = log(x)
Natural Logarithm (Base e):
ln(x) = logₑ(x)
Logarithm with Custom Base:
logₐ(x) = ln(x) / ln(a) = log(x) / log(a)

About Logarithms

A logarithm is the inverse operation of exponentiation. It answers the question: "To what power must we raise the base to get this number?" Common logarithms use base 10, while natural logarithms use base e (approximately 2.718).