Calculators
Logarithm Calculator
Calculate the logarithm of a positive number for any valid base locally in your browser.
Enter a value greater than zero and a positive base other than 1. For example, log base 2 of 8 is 3. The calculation runs locally in your browser; your values are not uploaded or stored.
Find a logarithm without uploading anything.
Enter a value greater than zero and a positive base other than 1 to see log base b of the value. Everything runs locally in your browser, so your values are not uploaded or stored.
Frequently Asked Questions
Everything you need to know about this tool, how it works, and privacy.
What is a logarithm?
A logarithm answers which exponent a base needs to produce a value. For example, log base 2 of 8 is 3 because 2 to the power of 3 is 8. Common logarithms use base 10 and natural logarithms use base e (about 2.71828).
What does the logarithm calculator show?
Enter a value greater than zero and a positive base other than 1. The calculator returns log base b of the value. For example, log_2(8) gives 3, while log_10(1000) gives 3.
Which inputs are accepted?
Enter a value greater than zero through 1000000000000000 and a base greater than zero through 1000000000000000, excluding 1. Decimal values are accepted. Zero, negative numbers, a base of 1, and values above the limit show a clear error instead of a result.
Do my numbers stay private?
Yes. The calculation and copy action run locally in your browser. CodeASystem does not upload or store the values you enter.