Logarithm Calculator

Use our free logarithm calculator to compute log base b of any number. Supports any positive base.

Math

Number

Base

Formula

The logarithm of a number is the exponent to which the base must be raised to produce that number. For example, log₁₀(100) = 2 because 10² = 100.

logₐ(N) = ln(N) / ln(a)

Percentage: The percentage value you want to apply

Number: The original number or value

Result: The calculated result

Result: 2

The natural logarithm (ln) uses base e (approximately 2.71828). Use the Natural Log Calculator for that.

Logarithms are only defined for positive numbers and positive bases (not equal to 1).

CalculateMe Team

Last updated: 2026-07-13