antilog calculator

Use this tool to find the antilogarithm (inverse log). Enter a logarithm value and choose a base to compute:

If log_b(y) = x, then y = b^x

Logarithm value (x)

This is the log result you already know.

Log base (b)

Custom base value

Decimal places (0–15)

What Is an Antilog?

An antilog is the inverse operation of a logarithm. If a logarithm tells you the exponent, the antilog gives you the original number. In practical terms, it “undoes” a log transformation.

For example, if:

log₁₀(200) ≈ 2.30103

then the antilog of 2.30103 in base 10 is approximately 200.

Antilog Formula

The core relationship is:

y = b^x

x = logarithm value
b = base of the logarithm
y = antilog result (original value)

So if you know x and b, you raise the base to that exponent to find the antilog.

How to Use This Antilog Calculator

Step-by-step

Enter your logarithm value in the first field.
Choose the base (10, e, 2, or custom).
Set the number of decimal places for display precision.
Click Calculate Antilog to get the result instantly.

The calculator also shows the exact expression used, so you can verify the math.

Common Types of Antilog Calculations

1) Base-10 Antilog (Common Log)

Often used in chemistry, acoustics, and engineering tables.

antilog(x) = 10^x

2) Base-e Antilog (Natural Log)

Used heavily in calculus, growth models, finance, and statistics.

antiln(x) = e^x

3) Base-2 Antilog

Common in computer science and information theory.

anti-log₂(x) = 2^x

Worked Examples

Example A: Base 10

Given x = 3 and base 10:

y = 10³ = 1000

Example B: Natural Antilog

Given x = 1.5 and base e:

y = e^1.5 ≈ 4.48168907

Example C: Custom Base

Given x = 4 and base 5:

y = 5⁴ = 625

Where Antilogs Are Used

pH chemistry: converting log concentration back to actual concentration.
Finance: reversing logarithmic return transformations.
Statistics: back-transforming log-scaled regression outputs.
Signal processing: converting decibel-like log values back to linear scale.
Population and growth models: recovering original quantities after log modeling.

Common Mistakes to Avoid

Using the wrong base (e.g., base 10 instead of base e).
Forgetting that base must be positive and not equal to 1.
Rounding too early when precision matters.
Confusing “log” notation across different textbooks or software.

Quick FAQ

Is antilog the same as exponentiation?

Yes. Taking an antilog is raising the base to the given logarithm value.

Can I compute antilog for negative logarithm values?

Absolutely. You’ll get a positive result between 0 and 1 for bases greater than 1.

Can the result be extremely large or small?

Yes. For big positive or negative inputs, the result may be shown in scientific notation for readability.