Antilog Calculator
Compute the antilogarithm — the inverse of a logarithm — for base 10, base e or any custom base.
How it works
antilog_b(x) = bˣ — the inverse of log_b · base 10: 10ˣ · base e: eˣ
The antilogarithm reverses a logarithm: if log base b of y equals x, then the antilog of x is y = bˣ. Base 10 is the “common” antilog used for slide rules, decibels and pH, while base e gives the natural exponential eˣ found throughout growth and decay. Whatever base you use, taking the log of the antilog returns the number you started with.
Worked example
The base-10 antilog of 2 is 10² = 100, because log₁₀(100) = 2. Switch to base e and the antilog of 2 is e² ≈ 7.389 — the same exponent, a different base.
Sources: Logarithm — Wikipedia
Frequently asked questions
What exactly is an antilog?
It’s the inverse of a logarithm. Where a log answers “what power gives this number,” the antilog answers “what number does this power give” — it simply computes bˣ.
What is the antilog in base 10 versus base e?
Base 10 antilog of x is 10ˣ (used in pH, decibels and scientific notation); base e antilog of x is eˣ, the natural exponential that models continuous growth.
Why must the base be positive?
Logarithms and their inverses are only defined for positive bases (and the base can’t be 1). A negative base would make bˣ jump between real and undefined values as x changes.
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This calculator is for educational purposes. Double-check important results before acting on them.