How to use the Log Calculator
The log calculator finds the logarithm of a number to any base.
What you need to enter
- Number x
- Base
The formula
log_b(x) = ln(x) ÷ ln(b). log₁₀ and ln are shown as well.
Worked example
Using the default values in the calculator:
- Number x: 100
- Base: 10
| log base b of x | 2 |
| Natural log (ln) | 4.605170186 |
| log₁₀ | 2 |
| log₂ | 6.6438561898 |
Tips for better results
- The number must be positive.
- The base cannot be 1.
Common mistakes to avoid
- Entering negative numbers.
- Confusing log and ln.