✓ Effortless Math · Free Tool

Logarithm Calculator

Enter a base b and an argument x to compute logᵦ(x) — with the common log, natural log, the change-of-base expression, and full step-by-step working.

Change of base:  logb(x) = ln(x) / ln(b)
log base b ( argument x ) = ?

The argument x must be positive. The base b must be positive and not equal to 1. Decimals are fine.

Results

Logarithm
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Common log — log₁₀(x)
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Natural log — ln(x)
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Change of base — ln(x) / ln(b)
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Step-by-step (change of base)