Everyday utility

Log Calculator

Calculate the logarithm of a number in any base, including log₁₀ (common log) and ln (natural log). Use this Data and utilities tool to enter your numbers, review the result, and understand the key assumptions before making the next decision.

What you get
A focused calculator, clear explanation, common questions, and useful next tools.
Quick intro
Calculator
Result
Explanation
Common questions
Related tools

Calculator tool

How this calculator works
The result depends on the numbers you enter and the assumptions shown below.

log_b(x) = ln(x) / ln(b). The common logarithm (log₁₀) and natural logarithm (ln, base e ≈ 2.71828) are most frequently used. Logarithms answer: 'to what power must the base be raised to get x?'

Review the inputs carefully and treat the output as an estimate. For decisions involving money, taxes, health, law, or security, compare the result with trusted professional guidance when needed.

Frequently asked questions

What is the difference between log and ln?

log without a base typically means log₁₀ (common log). ln is the natural logarithm with base e ≈ 2.71828, used extensively in calculus and science.