Logarithm Calculator
Calculate the logarithm of a number to any base, including base 10, base 2 and natural logs. Enter number and base to see logarithm when you calculate.
8 of 8 free uses remaining today
Calculate the logarithm of a number to any base, including base 10, base 2 and natural logs. Enter number and base to see logarithm when you calculate.
Worked example
Example calculated from the starting values. Enter your own values and press Calculate to get your result.
With the default inputs (number = 100, base = 10), the results are: logarithm 2.000000.
Quick reference: number vs result
Reference table based on the example values; it is not your calculation result.
| Number | Logarithm |
|---|---|
| 50 | 1.698970 |
| 100 | 2.000000 |
| 200 | 2.301030 |
| 500 | 2.698970 |
| 1,000 | 3.000000 |
| 2,000 | 3.301030 |
Frequently asked questions
What formula does this calculator use?
Logarithm = ln(x) ÷ ln(b). Variables: x = number, b = base.
What do I need to enter?
You need number, base. Results update as you type.
What is an example result?
With the default inputs (number = 100, base = 10), the results are: logarithm 2.000000.
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