Logarithm Calculator
Calculate logarithms of any base — common log (base 10), natural log (ln), or custom base logarithms.
How to Use the Logarithm Calculator
- 1
Enter the number
Input the number you want to find the logarithm of.
- 2
Select the base
Choose base 10 (log), base e (ln), base 2, or enter a custom base.
- 3
View the result
See the logarithm value calculated instantly.
💡 Tips & Tricks
- •log₁₀ is useful for orders of magnitude (Richter scale, decibels, pH).
- •ln is the "natural" choice for calculus and continuous growth problems.
- •Change of base formula: log_b(x) = log(x) / log(b) for any base.
Frequently Asked Questions
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