Question
What is a logarithm?
A logarithm tells you which exponent a base needs to reach a target value.
Math
Use OmniCalc's log calculator to find logarithms for any positive number and valid base instantly.
Log calculator
Enter a value and base to calculate the logarithm instantly, with natural log, common log, and a reconstruction check shown beside it.
Why this result matters
A natural next-step algebra utility after exponent and scientific notation, capturing direct logarithm intent. Use the tool above to enter a few clear inputs and get a practical answer you can use right away.
This log calculator helps students and everyday users calculate logarithms quickly for algebra, precalculus, and science work. Enter a value and base to see the logarithm, natural log, common log, and a power check in one place.
Formula and method
The calculator uses the change-of-base formula: log_b(x) = ln(x) / ln(b), where x is positive and b is positive but not equal to 1.
Example
If you enter value 1000 and base 10, the calculator returns 3 because 10^3 = 1000.
FAQ
Short answers to the questions people often ask before or after using the tool.
Question
A logarithm tells you which exponent a base needs to reach a target value.
Question
The input value must be greater than zero, and the base must be greater than zero and not equal to 1.
Question
Common log uses base 10, while natural log uses the constant e as the base.
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