How to use this calculator
A logarithm answers the question: to what exponent must the base be raised to produce the number?
The method
Enter your values in the labeled fields and choose Calculate. The result panel shows the answer and supporting values when useful.
Number: 1000, Base: 10
Select Calculate to evaluate these example values.
Scope and limitations
The number must be positive; the base must be positive and cannot equal 1. Uses real-number arithmetic and rounds display values without changing the entered inputs. Check important results independently.
Common questions
Can I use different units?
Use consistent units unless this page is a unit converter. The result follows the units implied by the inputs.
Are results exact?
Displayed values may be rounded. Keep extra precision for important follow-up calculations.
Methods & verification
Formulas use standard mathematical definitions and fixed unit factors where applicable. See our methodology for numerical conventions, rounding, privacy, and limitations.