Logarithm Calculator

Calculate logarithms and antilogarithms with different bases. Supports natural log (ln), base 10 (log), and custom bases.

Calculator

Must be greater than 0

Select a calculation type (Logarithm or Antilogarithm) and enter the required values to calculate.

Complete User Guide

What is a Logarithm?

A logarithm is the inverse operation of exponentiation. If b^y = x, then log_b(x) = y. The logarithm tells you what power you need to raise the base to get the number.

Common logarithms: log₁₀ (base 10) and ln (natural log, base e ≈ 2.71828).

Calculation Types

  • Logarithm: Calculate log_b(x) - the power to which base b must be raised to get x
  • Antilogarithm: Calculate b^x - raise base b to the power x (inverse of logarithm)

Examples

Example 1: Common Logarithm

Calculate: log₁₀(100)

Result: 2

Explanation: 10² = 100

Example 2: Natural Logarithm

Calculate: ln(e)

Result: 1

Explanation: e¹ = e

Example 3: Antilogarithm

Calculate: 10²

Result: 100

Explanation: Antilog of 2 with base 10

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