MihsabaHow to use
A logarithm answers: to what power must base b be raised to produce x? The tool supports ln, log10, log2, any positive custom base other than 1, and the inverse operation b^y.
- Choose the logarithm type or inverse mode.
- Enter positive x for a logarithm.
- For a custom base use b>0 and b≠1.
- For inverse mode enter base and exponent, then calculate.
How it is calculated
log_b(x)=ln(x)÷ln(b); b^y=x
Example
log10(1000)=3 because 10³=1000; ln(e)=1; log2(32)=5.
Important notes
For real-valued logarithms, x must be positive. The base must be positive and different from 1.
Frequently asked questions
ln vs log?
ln uses base e; log commonly means base 10.
Can x be zero?
Not for a real logarithm.
How is any base handled?
With log_b(x)=ln(x)/ln(b).
Is this calculator free?
Yes. It is free to use and requires no account.