Logarithm Calculator
Compute common log (log₁₀), natural log (ln), binary log (log₂), and a custom-base logarithm for any positive number.
Logarithm Mathematics
Logarithm calculator computes common log (log₁₀), natural log (ln), binary log (log₂), and a custom-base log for any positive number.
A logarithm answers "to what power must the base be raised to get this number?" Common log uses base 10, natural log uses base e (≈2.71828), and binary log uses base 2.
- 1Enter the number (argument) and, optionally, a custom base.
- 2View the common log, natural log, binary log, and custom-base log.
Compute several logarithms of 100.
Frequently Asked Questions (FAQ)
"log" (without a subscript, in most contexts) means log base 10, the common logarithm. "ln" specifically means the natural logarithm, base e (≈2.71828), which is the inverse of the exponential function eˣ.
Because no real exponent applied to a positive base ever produces a negative result or zero — the logarithm function is only defined for positive arguments in the real number system.
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