Logarithm Calculator

How to calculate logarithm

This tool calculates logarithm from Number, Base. Enter each quantity in its labelled field, then use the formula below to check the calculation.

Formula

ln(number) ÷ ln(base)

Worked example

Number

100

Base

10

Applying the formula to these values gives 2 .

What should I check?

Calculate powers, roots, logarithms, ratios, slopes and trigonometric functions. Trigonometric angles are entered in degrees.

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