Log Calculator (Logarithm)

Calculate any of the three values in the logarithm equation logb(x) = y

Calculate any value in the logarithm equation logb(x) = y.

About Logarithms

A logarithm is the inverse operation to exponentiation. It answers: "To what power must the base be raised to get the number?"

Logarithm Formula:

logb(x) = y means by = x

  • b = base (positive, ≠ 1)
  • x = number (positive)
  • y = result

Common Logs:

  • • ln(x) = loge(x)
  • • log(x) = log10(x)
  • • lb(x) = log2(x)

Properties:

  • • logb(1) = 0
  • • logb(b) = 1
  • • logb(xy) = logb(x) + logb(y)

Applications:

  • • Sound (decibels)
  • • pH scale
  • • Richter scale
  • • Algorithm complexity

Common Values:

  • • ln(e) = 1
  • • log10(100) = 2
  • • log2(8) = 3

Calculate Logarithm

=

logb(x) = y