±Free
Logarithm calculator
Find log base b of a positive number.
Enter a positive value and a positive base different from 1. The result is computed as ln(value) / ln(base), giving the exponent to which the base must be raised.
How to use
- Enter your text, values, or image.
- Adjust the options and run the tool.
- Copy or download your result.
Worked example
Example input
Positive value: 100 Base (positive, not 1): 10
Example result
2
Limitations and details
Zero and negative values, and bases equal to zero or one, are rejected; results use real floating-point arithmetic.
Inputs and options
- Positive value
- Number
- Base (positive, not 1)
- Number
Frequently asked questions
Is this tool free and private?
Yes. All 300 tools are free in this phase. Processing happens in your browser; your input and files are not sent to our servers.