Logarithm Calculator

All tools

Compute the logarithm of any value in any base using the change-of-base formula, with quick presets for natural log, log base 10 and log base 2. Free and instant.

Result –
Natural log — ln(x) –
Common log — log₁₀(x) –
Binary log — log₂(x) –
The result uses the change-of-base formula logb(x) = ln(x) ÷ ln(b). The value must be positive and the base must be positive and not equal to 1.
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