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Logarithm Calculator

Calculate log₁₀, ln, log₂, and custom base logarithms

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Result

About Logarithm Calculator

Compute logarithms in any base with common identities, change-of-base formula, and antilog. Supports log₁₀, natural log (ln), log₂, and custom bases.

Step by Step

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Tips

  • log₁₀ is used for decibels and pH scales
  • ln (natural log) is essential in calculus and compound interest
  • log₂ is fundamental in computer science (bits, binary search)

Frequently Asked Questions

What is a logarithm?
The inverse of exponentiation — log_b(x) asks 'what power of b gives x?' For example, log₂(8) = 3 because 2³ = 8.
Why is log(0) undefined?
No finite exponent can make a positive base equal zero. As x approaches 0, log(x) approaches negative infinity.