Logarithm Calculator

Calculate logarithms with different bases, natural logarithms, and common logarithms.

Common Logarithm (Base 10)

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A logarithm is the power to which a number (the base) must be raised to produce a given number.

If b^y = x, then log_b(x) = y

Example: log₁₀(100) = 2 because 10² = 100

The logarithm with base 10, often written as log(x) without an explicit base.

log₁₀(x) or simply log(x)

Used in engineering, physics, and for measuring quantities that vary over many orders of magnitude.

The logarithm with base e (≈ 2.71828), written as ln(x).

ln(x) = log_e(x)

Used in calculus, statistics, and for describing natural growth and decay processes.