This online calculator produces the logarithm of a given number with a given base. It computes also the natural logarithm and the common logarithm (decimal logarithm).

The Logarithm is the inverse operation to exponentiation. Suppose we have the exponentiation N=x^a, then the logarithm of N with base a equals to x, or x=log_{a}{N}
To compute the logarithm with an arbitrary base just enter your number and base in the corresponding calculator fields:



Digits after the decimal point: 3
Logarithm to a given base
Common logarithm
Natural logarithm
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The calculator uses the following formula to get the algorithm with arbitrary base:
log_a b =\frac{log_c b}{log_c a}

In addition the calculator gives a base-10 logarithm (common logarithm) and natural logarithm of the given number.