Inverse Log Calculator

Enter Calculation

Enter a number:

Select base: 10 (Common log) e (Natural log) 2 (Binary log)

Results

10² = 100

Input Number (Exponent)	2
Base	10
Antilog Result	100

What the Inverse Log (Antilog) Calculator Does

The inverse logarithm — also called the antilogarithm — reverses a logarithm. If you know the log of a number, the antilog gives you the original number back. This calculator takes a single value and raises your chosen base to that power. In other words, it computes base^x, where x is the number you enter and base is the one you pick from the list.

The Inputs You Provide

• Enter a number — the exponent x. This can be any positive, negative, or decimal value (for example 2, -1.5, or 0.301).
• Select base — choose one of three options:
  • 10 (Common log) — calculates 10^x, the inverse of log₁₀.
  • e (Natural log) — calculates e^x (≈ 2.71828^x), the inverse of ln.
  • 2 (Binary log) — calculates 2^x, the inverse of log₂.

The Formula

The calculator applies one simple rule depending on the base you select:

• Base 10: antilog = 10^x
• Base e: antilog = e^x (the exponential function)
• Base 2: antilog = 2^x

Each is the exact mathematical inverse of its matching logarithm, so if log₁₀(100) = 2, then the antilog of 2 in base 10 returns 100.

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The antilog reverses the logarithm: applying base^x undoes log.

Worked Example

Suppose you enter 3 and select base 10. The calculator computes 10³ = 1000. If instead you enter 0.301 with base 10, you get 10^0.301 ≈ 2.0 — which makes sense, because log₁₀(2) ≈ 0.301. Switching the base to e with the number 1 returns e¹ ≈ 2.71828, and base 2 with the number 10 returns 2¹⁰ = 1024.

Antilog curves for the three bases: 10^x, e^x, and 2^x.

Frequently Asked Questions

What is an antilog? An antilog undoes a logarithm. Since a logarithm asks "to what power do I raise the base to get this number?", the antilog simply performs that exponentiation: base^x.

Can I enter a negative or decimal number? Yes. Negative exponents return fractions (for example base 10 with -2 gives 0.01), and decimals are handled precisely (10^0.5 ≈ 3.162).

Why are there only three bases? Base 10 (common), base e (natural), and base 2 (binary) cover the logarithms used most often in science, mathematics, and computing. These three match the standard log, ln, and log₂ functions you will encounter most frequently.