Antilog Calculator
This antilog calculator undoes a logarithm. Example: to the base 10, x = 2.5 gives 316.228, because 10^2.5 = 316.228.
Example: Base: 10 (common) · Logarithm value x 2.5 → Result: Antilog base 10 of 2.5 = 316.228. Source: Wikipedia – Logarithm (inverse function). Updated: .
How it is calculated
The antilogarithm is the inverse function of the logarithm: from the logarithm x of a number you get the number back. It is written antilog_b(x) and is simply the power b^x.
Formula and steps
If log_b(y) = x, then y = b^x. For base 10 you compute 10^x, for base e (Euler’s number 2.71828) e^x and for base 2 accordingly 2^x. The base must be positive and not equal to 1. As a check, take the logarithm of the result and you get x again.
Worked examples
For log₁₀(y) = 2.5 we get y = 10^2.5 = 100 · 3.16228 ≈ 316.228. To base e, x = 2 gives e² ≈ 7.38906. To base 2, x = 7 gives 2^7 = 128, and with the custom base 3 and x = 4 you get 81. Negative values lead to numbers between 0 and 1: 10^(−2) = 0.01.
- The antilog is always positive, even when x is negative.
- On a scientific calculator use the 10^x or e^x keys, often the second function of log and ln.
Frequently asked questions
What is an antilogarithm?
The inverse of the logarithm. If the logarithm of a number is x, you recover the number with b^x.
How do I find the antilog of 2.5 to base 10?
Compute 10^2.5 ≈ 316.228. Check: log₁₀(316.228) = 2.5.
Which base should I choose?
The base that was used for the logarithm: 10 for common logarithms (log), e for natural ones (ln), 2 for binary ones. For other bases enter it yourself.
Sources and legal basis
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