How it works
A logarithm answers the question: which exponent on the base produces the value? The base must be positive and cannot equal 1, while the value must be positive.
Standard formula
log_base(value) = ln(value) ÷ ln(base)Worked example
log base 10 of 100 is 2 because 10² = 100.
Frequently Asked Questions
What bases are allowed?
The base must be greater than zero and different from one.
What is the natural logarithm?
It is the logarithm with base e, approximately 2.71828.
Can the value be zero?
No. Real logarithms are defined only for positive values.
Are results rounded?
The display is rounded for readability while the calculation keeps the numeric precision available in the browser.