Log Calculator
Result
log₍10₎(100)2
Natural log ln(x) log base e4.605170186
Common log log₁₀(x)2
Binary log log₂(x)6.6438561898
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Log Calculator — free online calculator.
Formula
log_b(x) = ln(x) / ln(b). Natural log: ln(x) = log_e(x). Change of base: log_b(x) = log_10(x) / log_10(b).
- Log Calculator calculates its result from Log 10, X, B. It uses the formula log_b(x) = ln(x) / ln(b). Natural log: ln(x) = log_e(x). Change of base: log_b(x) = log_10(x) / log_10(b).. Change any input to recalculate the result instantly.
- The main inputs are Number, Logarithm base, Custom base. Enter them in the units and format shown in the calculator.
- Keep comparable quantities in compatible units whenever the formula combines or compares them.
- Changing any input above recalculates the result with the same calculation engine used by this page.
Example: Log
Inputs
- Number: 100
- Logarithm base: 10
- Custom base: 3
Using Log 10 = 2, X = 3, B = 4, the calculated result is 12.
Sample result: Calculating…
Frequently asked questions
What does the Log calculate?
Log Calculator — free online calculator.
Which values should I enter?
Enter Number, Logarithm base, Custom base using the units and format shown beside each field.
What formula does this calculator use?
The calculator uses the following relationship: log_b(x) = ln(x) / ln(b). Natural log: ln(x) = log_e(x). Change of base: log_b(x) = log_10(x) / log_10(b)..
Why might my result differ from another source?
Results can differ when another source uses different units, rounding rules, conventions or assumptions. Compare the inputs and definitions before comparing results.
Does the result update automatically?
Yes. Changing an input updates the result using the same calculation engine shown on this page.