Enter a logarithm value and a base to find the antilog — the number that logarithm came from.
How to Use the Antilog Calculator
Enter the logarithm value and a base — type any number into the base field, or click "Natural (e)" to switch to the natural log base without retyping anything else.
An antilog undoes a logarithm, in the same literal sense that subtraction undoes addition. If log_b(x) = y, then antilog_b(y) = x — running the log operation backward, from the exponent back to the original number it came from.
antilog_b(y) = b^yThat's the whole operation: raise the base to the power of whatever value you're taking the antilog of. Enter 2 with base 10 — the calculator's defaults — and you get 100, because log10(100) = 2. The two statements are mirror images of the same fact, not two separate things to learn.
This sounds almost too obvious to bother stating, and that's exactly why it trips people up. Logarithms get introduced as their own operation, with their own button on a scientific calculator and their own rules to memorize, which makes "taking the antilog" feel like it should be its own separate procedure too. It isn't. Antilog is exponentiation, full stop, using whatever base the original logarithm used. Change the base and the calculator changes which exponentiation it runs — the mechanism underneath never changes.
Base e (approximately 2.71828) shows up constantly in calculus and continuous-growth problems, which is why it gets its own button here instead of requiring anyone to type "2.71828183" by hand.