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Logarithm Calculator

Logarithms are the inverse of exponential functions and appear throughout science, engineering, and finance.

Calculated Result
2

Logarithm

log10(100)

2

Natural log ln(x)

4.605170186

log base 10

2

log base 2

6.6438561898

2 — Logarithm

Calculation Breakdown

  1. Change of baselog_b(x) = ln(x) / ln(b)log⁡bx=ln⁡xln⁡b\log_b x = \dfrac{\ln x}{\ln b}
  2. Resultlog_10(100) = 2

log₁₀(x) for Common Values

Interactive visualization based on your current inputs

Calculated Value
0.01.02.03.04.0log(10) = 1log(100) = 2log(1000) = 3log(10000) = 4

What Is the Logarithm Calculator?

A logarithm answers: "to what power must b be raised to get x?" — logb(x) = y means bʸ = x.

How Does the Logarithm Calculator Work?

The change-of-base formula converts any logarithm to natural log: log_b(x) = ln(x)/ln(b).

Logarithm Calculator Formula & Variables

The core mathematical equation utilized by this calculator is expressed as:

log⁡bx=ln⁡xln⁡b\log_b x = \dfrac{\ln x}{\ln b}

Change-of-base formula. ln is the natural logarithm (base e ≈ 2.718).

How to Use the Logarithm Calculator

  1. Enter x > 0 and a base ≠ 1 to get all four logarithm values simultaneously.

Step-by-Step Example Calculation

log₁₀(100)

Input Values:

value:100
base:10
Worked Steps: log₁₀(100) = 2, since 10² = 100.

Understanding Your Result

log₁₀ is common log; ln is natural log; log₂ is binary log used in computing.

Factors That Affect the Result

  • log(1) = 0 for any base. log of values between 0 and 1 is negative.

When Should You Use This Calculator?

  • pH chemistry, decibels (dB), earthquake magnitude, complexity analysis (O(log n)).

Assumptions & Limitations

  • x > 0; base > 0 and base ≠ 1.

Frequently Asked Questions

Calculation Accuracy & Reference Note

Uses IEEE 754 Math.log(); accurate to ~15 significant figures.

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